Stethoscope Cleaning During Patient Care.

PubMed

Ghumman, Ghazi Wahla; Ahmad, Nina; Pop-Vicas, Aurora; Iftikhar, Sadia

2018-05-01

We conducted a cross-sectional survey of healthcare workers in two community teaching hospitals to better understand clinicians' beliefs and practices related to cleaning of their stethoscopes. The study was conducted from September 2015 to May 2016. Among the total 358 responses received, 45%, 40%, 10% and 5% were from attending physicians, medical students, nurses, and resident physicians, respectively. Although the majority of the respondents (76%) frequently used a stethoscope at work, and almost all (93%) believed that stethoscopes can be involved in pathogen transmission, only 29% of participants reported cleaning their stethoscopes after every use. Hospitals should include stethoscope cleaning into their overall infection prevention efforts. [Full article available at http://rimed.org/rimedicaljournal-2018-05.asp].

Stethoscope Hygiene: Practice and Attitude of Medical Students

PubMed Central

Gazibara, Tatjana; Radovanovic, Sanja; Maric, Gorica; Rancic, Biljana; Kisic-Tepavcevic, Darija; Pekmezovic, Tatjana

2015-01-01

Objective The purpose of this study was to evaluate the frequency and attitude of medical students towards cleaning their stethoscopes. Subjects and Methods A cross-sectional study was carried out in the first week of December 2013. The study included 771 students (397 in their fourth and 374 in their sixth year) from the Faculty of Medicine, University of Belgrade, Serbia. An anonymous questionnaire was distributed to students before the start of compulsory lessons in classrooms. Results 317 of the 397 fourth-year students (79.8%) and 306 of the 374 sixth-year students (81.9%) cleaned their stethoscope. The stethoscope diaphragm was most commonly cleaned, while the flexible tubing was the least commonly cleaned area, mainly using ethyl alcohol-based agents. The strongest positive attitude was observed for the statement ‘It is important that my stethoscope is clean’ (4.3 out of 5.0). A positive correlation (Spearman's ρ = 0.105) was observed between a higher frequency of cleaning and the stronger positive notion that a stethoscope should be cleaned. Conclusion A considerably high proportion of the students studied had ever cleaned their stethoscopes. Based on the students' responses, it would be useful to implement instructions on stethoscope hygiene in the regular practical curriculum with the aim of applying stethoscope disinfection in daily work. PMID:26202790

Stethoscope Hygiene: Practice and Attitude of Medical Students.

PubMed

Gazibara, Tatjana; Radovanovic, Sanja; Maric, Gorica; Rancic, Biljana; Kisic-Tepavcevic, Darija; Pekmezovic, Tatjana

2015-01-01

The purpose of this study was to evaluate the frequency and attitude of medical students towards cleaning their stethoscopes. A cross-sectional study was carried out in the first week of December 2013. The study included 771 students (397 in their fourth and 374 in their sixth year) from the Faculty of Medicine, University of Belgrade, Serbia. An anonymous questionnaire was distributed to students before the start of compulsory lessons in classrooms. 317 of the 397 fourth-year students (79.8%) and 306 of the 374 sixth-year students (81.9%) cleaned their stethoscope. The stethoscope diaphragm was most commonly cleaned, while the flexible tubing was the least commonly cleaned area, mainly using ethyl alcohol-based agents. The strongest positive attitude was observed for the statement 'It is important that my stethoscope is clean' (4.3 out of 5.0). A positive correlation (Spearman's x03C1; = 0.105) was observed between a higher frequency of cleaning and the stronger positive notion that a stethoscope should be cleaned. A considerably high proportion of the students studied had ever cleaned their stethoscopes. Based on the students' responses, it would be useful to implement instructions on stethoscope hygiene in the regular practical curriculum with the aim of applying stethoscope disinfection in daily work. © 2015 S. Karger AG, Basel.

Ethanol-based cleanser versus isopropyl alcohol to decontaminate stethoscopes.

PubMed

Lecat, Paul; Cropp, Elliott; McCord, Gary; Haller, Nairmeen Awad

2009-04-01

Approximately 1 in 20 hospital admissions is complicated by a health care-associated infection. Stethoscopes may play a role in spreading nosocomial infections. The objective of this study was to determine the effectiveness of an ethanol-based cleanser (EBC) compared with isopropyl alcohol pads in reducing bacterial contamination of stethoscope diaphragms. Stethoscopes were cultured from medical professionals on 4 medical floors before and after cleaning with either EBC or isopropyl alcohol pads. The numbers of colony-forming units (cfu) grown were compared between the 2 cleaners and to baseline values. A total of 99 stethoscopes were cultured (49 EBC; 50 isopropyl alcohol), and all were positive for growth. After cleaning, 28.28% of the stethoscopes were growth-free (12 EBC; 16 isopropyl alcohol). Cleaning with EBC and isopropyl alcohol pads significantly reduced the cfu counts (by 92.8% and 92.5%, respectively), but neither was found to be statistically superior (F = 1.22; P = .2721). Cleaning a stethoscope diaphragm using either EBC or isopropyl alcohol led to a significant reduction in bacterial growth in culture. As an extension of the hand, a stethoscope should be cleaned with the same frequency as the hands. The simultaneous cleaning of hands and stethoscope may further increase compliance with current standards.

Comparison of traditional and sensor-based electronic stethoscopes in beagle dogs.

PubMed

Szilvási, Viktória; Vörös, Károly; Manczur, Ferenc; Reiczigel, Jenő; Novák, István; Máthé, Akos; Fekete, Dániel

2013-03-01

The objective of this study was to compare the auscultatory findings using traditional and electronic sensor-based stethoscopes. Thirty-three adult healthy Beagles (20 females, 13 males, mean age: 4.8 years, range 1.4-8 years) were auscultated by four investigators with different experiences (INVEST-1, -2, -3 and -4) independently with both stethoscopes. Final cardiological diagnoses were established by echocardiography. Mitral murmurs were heard with both stethoscopes by all investigators and echocardiography revealed mild mitral valve insufficiency in 7 dogs (21%, 4 females, 3 males). The statistical sensitivity (Se) in recognising cardiac murmurs proved to be 82% using the traditional stethoscope and 75% using the electronic one in the mean of the four examiners, whilst statistical specificity (Sp) was 99% by the traditional and 100% by the electronic stethoscope. The means of the auscultatory sensitivity differences between the two stethoscopes were 0.36 on the left and 0.59 on the right hemithorax, demonstrating an advantage for the electronic stethoscope being more obvious above the right hemithorax (P = 0.0340). The electronic stethoscope proved to be superior to the traditional one in excluding cardiac murmurs and especially in auscultation over the right hemithorax. Mitral valve disease was relatively common in this clinically healthy research Beagle population.

Brief report: pulmonary auscultation in the operating room: a prospective randomized blinded trial comparing electronic and conventional stethoscopes.

PubMed

Hoffmann, Clement; Falzone, Elisabeth; Verret, Catherine; Pasquier, Pierre; Leclerc, Thomas; Donat, Nicolas; Jost, Daniel; Mérat, Stephane; Maurice, Guillaume de Saint; Lenoir, Bernard; Auroy, Yves; Tourtier, Jean-Pierre

2013-09-01

We compared the subjective quality of pulmonary auscultation between 2 acoustic stethoscopes (Holtex Ideal® and Littmann Cardiology III®) and an electronic stethoscope (Littmann 3200®) in the operating room. A prospective double-blind randomized study with an evaluation during mechanical ventilation was performed in 100 patients. After each examination, the listeners using a numeric scale (0-10) rated the quality of auscultation. Auscultation quality was compared in patients among stethoscopes with a multilevel mixed-effects linear regression with random intercept (operator effect), adjusted on significant factors in univariate analysis. A significant difference was defined as P < 0.05. One hundred comparative evaluations of pulmonary auscultation were performed. The quality of auscultation was rated 8.2 ± 1.6 for the electronic stethoscope, 7.4 ± 1.8 for the Littmann Cardiology III, and 4.6 ± 1.8 for the Holtex Ideal. Compared with Holtex Ideal, auscultation quality was significantly higher with other stethoscopes (P < 0.0001). Compared with Littmann Cardiology III, auscultation quality was significantly higher with Littmann 3200 electronic stethoscope (β = 0.9 [95% confidence interval, 0.5-1.3]). An electronic stethoscope can provide a better quality of pulmonary auscultation than acoustic stethoscopes in the operating room, yet with a magnitude of improvement marginally higher than that provided with a high performance acoustic stethoscope. Whether this can translate into a clinically relevant benefit requires further studies.

Does the position or contact pressure of the stethoscope make any difference to clinical blood pressure measurements: an observational study.

PubMed

Pan, Fan; Zheng, Dingchang; He, Peiyu; Murray, Alan

2014-12-01

This study aimed to investigate the effect of stethoscope position and contact pressure on auscultatory blood pressure (BP) measurement. Thirty healthy subjects were studied. Two identical stethoscopes (one under the cuff, the other outside the cuff) were used to simultaneously and digitally record 2 channels of Korotkoff sounds during linear cuff pressure deflation. For each subject, 3 measurements with different contact pressures (0, 50, and 100 mm Hg) on the stethoscope outside the cuff were each recorded at 3 repeat sessions. The Korotkoff sounds were replayed twice on separate days to each of 2 experienced listeners to determine systolic and diastolic BPs (SBP and DBP). Variance analysis was performed to study the measurement repeatability and the effect of stethoscope position and contact pressure on BPs. There was no significant BP difference between the 3 repeat sessions, between the 2 determinations from each listener, between the 2 listeners and between the 3 stethoscope contact pressures (all P > 0.06). There was no significant SBP difference between the 2 stethoscope positions at the 2 lower stethoscope pressures (P = 0.23 and 0.45), but there was a small (0.4 mm Hg, clinically unimportant) significant difference (P = 0.005) at the highest stethoscope pressure. The key result was that, DBP from the stethoscope under the cuff was significantly lower than that from outside the cuff by 2.8 mm Hg (P < 0.001, 95% confidence interval -3.5 to -2.1 mm Hg). Since it is known that the traditional Korotkoff sound method, with the stethoscope outside the cuff, tends to give a higher DBP than the true intra-arterial pressure, this study could suggest that the stethoscope position under the cuff, and closer to the arterial occlusion, might yield measurements closer to the actual invasive DBP.

Does the Position or Contact Pressure of the Stethoscope Make Any Difference to Clinical Blood Pressure Measurements

PubMed Central

Pan, Fan; Zheng, Dingchang; He, Peiyu; Murray, Alan

2014-01-01

Abstract This study aimed to investigate the effect of stethoscope position and contact pressure on auscultatory blood pressure (BP) measurement. Thirty healthy subjects were studied. Two identical stethoscopes (one under the cuff, the other outside the cuff) were used to simultaneously and digitally record 2 channels of Korotkoff sounds during linear cuff pressure deflation. For each subject, 3 measurements with different contact pressures (0, 50, and 100 mm Hg) on the stethoscope outside the cuff were each recorded at 3 repeat sessions. The Korotkoff sounds were replayed twice on separate days to each of 2 experienced listeners to determine systolic and diastolic BPs (SBP and DBP). Variance analysis was performed to study the measurement repeatability and the effect of stethoscope position and contact pressure on BPs. There was no significant BP difference between the 3 repeat sessions, between the 2 determinations from each listener, between the 2 listeners and between the 3 stethoscope contact pressures (all P > 0.06). There was no significant SBP difference between the 2 stethoscope positions at the 2 lower stethoscope pressures (P = 0.23 and 0.45), but there was a small (0.4 mm Hg, clinically unimportant) significant difference (P = 0.005) at the highest stethoscope pressure. The key result was that, DBP from the stethoscope under the cuff was significantly lower than that from outside the cuff by 2.8 mm Hg (P < 0.001, 95% confidence interval −3.5 to −2.1 mm Hg). Since it is known that the traditional Korotkoff sound method, with the stethoscope outside the cuff, tends to give a higher DBP than the true intra-arterial pressure, this study could suggest that the stethoscope position under the cuff, and closer to the arterial occlusion, might yield measurements closer to the actual invasive DBP. PMID:25546675

Stethoscopes with hearing aid use: Case studies

PubMed Central

Jacob, Regina Tangerino de Souza; Zambonato, Ticiana Cristina de Souza; Mondelli, Maria Fernanda Capoani Garcia

2013-01-01

Summary Introduction: Description for using stethoscopes adapted to hearing aids. Aim: To describe the adaptation of HAs to stethoscopes used by 2 students in the health field with bilateral hearing impairment. Case reports: Two subjects with hearing loss had their stethoscopes coupled to HAs because of the individual requirements of their professions (healthcare) to perform auscultation. Conclusion: The improvement was measured in situ, and satisfaction was evaluated using a subjective questionnaire. The use of a stethoscope coupled to an HA allowed students with hearing loss to perform auscultation. PMID:25992000

Auscultation in flight: comparison of conventional and electronic stethoscopes.

PubMed

Tourtier, J P; Libert, N; Clapson, P; Tazarourte, K; Borne, M; Grasser, L; Debien, B; Auroy, Y

2011-01-01

The ability to auscultate during air medical transport is compromised by high ambient-noise levels. The aim of this study was to assess the capabilities of a traditional and an electronic stethoscope (which is expected to amplify sounds and reduce ambient noise) to assess heart and breath sounds during medical transport in a Boeing C135. We tested one model of a traditional stethoscope (3MTM Littmann Cardiology IIITM) and one model of an electronic stethoscope (3MTM Littmann Stethoscope Model 3000). We studied heart and lung auscultation during real medical evacuations aboard a medically configured C135. For each device, the quality of auscultation was described using a visual rating scale (ranging from 0 to 100 mm, 0 corresponding to "I hear nothing," 100 to "I hear perfectly"). Comparisons were accomplished using a t-test for paired values. A total of 36 comparative evaluations were performed. For cardiac auscultation, the value of the visual rating scale was 53 ± 24 and 85 ± 11 mm, respectively, for the traditional and electronic stethoscope (paired t-test: P = .0024). For lung sounds, quality of auscultation was estimated at 27 ± 17 mm for traditional stethoscope and 68 ± 13 for electronic stethoscope (paired t-test: P = .0003). The electronic stethoscope was considered to be better than the standard model for hearing heart and lung sounds. Flight practitioners involved in air medical evacuation in the C135 aircraft are better able to practice auscultation with this electronic stethoscope than with a traditional one. Copyright © 2011 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.

Predictors of Heavy Stethoscope Contamination Following a Physical Examination.

PubMed

Tschopp, Clément; Schneider, Alexis; Longtin, Yves; Renzi, Gesuele; Schrenzel, Jacques; Pittet, Didier

2016-06-01

BACKGROUND The degree of bacterial contamination of stethoscopes can vary significantly following a physical examination. OBJECTIVE To conduct a prospective study to investigate the impact of various environmental and patient characteristics on stethoscope contamination. METHODS Following a standardized examination, the levels of bacterial contamination of 4 regions of the physicians' hands and 2 sections of the stethoscopes, and the presence of different pathogenic bacteria, were assessed. Predictors of heavy stethoscope contamination were identified through multivariate logistic regression. RESULTS In total, 392 surfaces were sampled following examination of 56 patients. The microorganisms most frequently recovered from hands and stethoscopes were Enterococcus spp. (29% and 20%, respectively) and Enterobacteriaceae (16% and 7%, respectively). Staphylococcus aureus (either methicillin susceptible or resistant), extended-spectrum β-lactamase-producing Enterobacteriaceae, and Acinetobacter baumannii were recovered from 4%-9% of the samples from either hands or stethoscopes. There was a correlation between the likelihood of recovering these pathogens from the stethoscopes vs from the physicians' hands (ρ=0.79; P=.04). The level of patient's skin contamination was an independent predictor of contamination of the stethoscope diaphragm (adjusted odds ratio [aOR], 1.001; P=.007) and tube (aOR, 1.001; P=.003). Male sex (aOR, 28.24; P=.01) and reception of a bed bath (aOR, 7.52; P=.048) were also independently associated with heavy tube contamination. CONCLUSIONS Stethoscope contamination following a single physical examination is not negligible and is associated with the level of contamination of the patient's skin. Prevention of pathogen dissemination is needed. Infect Control Hosp Epidemiol 2016;37:673-679.

Bacterial contamination of stethoscopes used by health workers: public health implications.

PubMed

Uneke, Chigozie J; Ogbonna, Annayo; Oyibo, Patrick G; Onu, Christian M

2010-08-04

This study was designed to assess both the potential for bacterial transmission by stethoscopes used by health-care workers in Nigeria and the implications for patient safety and control of hospital-acquired infections. A structured questionnaire was administered to health workers and the surface of the diaphragm of their stethoscopes swabbed for bacteriological analysis using standard techniques. Of the 107 stethoscopes surveyed, 84 (79%) were contaminated with bacteria; 59 (81%) of the contaminated stethoscopes belonged to physicians and 25 (74%) were from other health workers. Isolates included Staphylococcus aureus (54%), Pseudomonas aeruginosa (19%), Enterococcus faecalis (14%), and Escherichia coli (13%). All stethoscopes that had never been cleaned were contaminated while lower levels of contamination were found on those cleaned one week or less before the survey (chi(2) = 22.4, P < .05). Contamination was significantly higher on stethoscopes cleaned with only water (100%) compared to those cleaned with alcohol (49%) (chi(2) = 30.17, P < .05). Significantly fewer (9%) stethoscopes from health workers who washed their hands after seeing each patient were contaminated when compared with the instruments (86%) of those who did not practice hand washing (chi(2) = 23.79, P < .05). E. coli showed the highest antibiotic resistance, while S. aureus showed the highest antibiotic susceptibility. Strict adherence to stethoscope disinfection practices by health workers can minimize cross-contamination and ensure improved patient safety in hospital environments.

Stethoscope versus point-of-care ultrasound in the differential diagnosis of dyspnea: a randomized trial.

PubMed

Özkan, Behzat; Ünlüer, Erden E; Akyol, Pinar Y; Karagöz, Arif; Bayata, Mehmet S; Akoğlu, Haldun; Oyar, Orhan; Dalli, Ayşe; Topal, Fatih E

2015-12-01

We aimed to determine the accuracies of point-of-care ultrasound (PoCUS) and stethoscopes as part of the physical examinations of patients with dyspnea. Three emergency medicine specialists in each of two groups of ultrasound and stethoscope performers underwent didactic and hands-on training on PoCUS and stethoscope usage. All the patients enrolled were randomized to one of two predetermined PoCUS or stethoscope groups. The diagnostic performance of ultrasonography was higher than that of the stethoscope in the diagnoses of heart failure (90 vs. 86%, 1.00 vs. 0.89, and 5.00 vs. 4.92, respectively) and pneumonia (90 vs. 86.7%, 0.75 vs. 0.73, and 16.50 vs. 13.82, respectively). No significant differences were observed in the utility parameters of these modalities in these diagnoses. Although some authors argue that it is time to abandon the 'archaic tools' of past centuries, we believe that it is too early to discontinue the use of the stethoscope.

21 CFR 870.1875 - Stethoscope.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) Identification. A manual stethoscope is a mechanical device used to project the sounds associated with the heart... stethoscope is an electrically amplified device used to project the sounds associated with the heart, arteries...

21 CFR 870.1875 - Stethoscope.

Code of Federal Regulations, 2011 CFR

2011-04-01

...) Identification. A manual stethoscope is a mechanical device used to project the sounds associated with the heart... stethoscope is an electrically amplified device used to project the sounds associated with the heart, arteries...

21 CFR 870.1875 - Stethoscope.

Code of Federal Regulations, 2012 CFR

2012-04-01

...) Identification. A manual stethoscope is a mechanical device used to project the sounds associated with the heart... stethoscope is an electrically amplified device used to project the sounds associated with the heart, arteries...

21 CFR 870.1875 - Stethoscope.

Code of Federal Regulations, 2014 CFR

2014-04-01

...) Identification. A manual stethoscope is a mechanical device used to project the sounds associated with the heart... stethoscope is an electrically amplified device used to project the sounds associated with the heart, arteries...

21 CFR 870.1875 - Stethoscope.

Code of Federal Regulations, 2013 CFR

2013-04-01

...) Identification. A manual stethoscope is a mechanical device used to project the sounds associated with the heart... stethoscope is an electrically amplified device used to project the sounds associated with the heart, arteries...

Bacterial contamination, bacterial profile and antimicrobial susceptibility pattern of isolates from stethoscopes at Jimma University Specialized Hospital

PubMed Central

2013-01-01

Introduction Hospital acquired infections are recognized as critical public health problems. Infections are frequently caused by organisms residing in healthcare environment, including contaminated medical equipment like Stethoscopes. Objective To determine bacterial contamination, bacterial profile and anti-microbial susceptibility pattern of the isolates from stethoscopes at Jimma University Specialized Hospital. Methodology Cross-sectional study conducted from May to September 2011 at Jimma University Specialized Hospital. One hundred seventy-six stethoscopes owned by Health Care Workers (HCWs) and Medical students were randomly selected and studied. Self-administered structured questionnaire was used to collect socio-demographic data. Specimen was collected using moisten sterile cotton swab and 1 ml normal saline was used to transport the specimen, all laboratory investigations were done following standard microbiological techniques, at Microbiology Laboratory, Jimma University. SPSS windows version 16 used for data analysis and P <0.05 was considered statistically significant. Result: A total, of 151 (85.8%) stethoscopes were contaminated. A total of 256 bacterial strains and a mean of 1.44×104 CFUs/diaphragm of stethoscopes was isolated. Of the 256 isolates, 133 (52%) were potential pathogens like S. aureus, Klebsiella spp., Citrobacter spp., Salmonella spp., Proteus spp., Enterobacter spp., P. aeruginosa and E. coli. All strains were resistant to multiple classes of antibiotics (two to eight classes of antibiotics). Disinfection practice was poor. Disinfection practice was found to be associated with bacterial contamination of stethoscopes (P < 0.05). High contamination rate 100 (90.9%) was observed among stethoscopes that had never been disinfected; while the least contamination 29 (72.2%) was found on those disinfected a week or less before the survey. Conclusion Bacterial contamination of the stethoscope was significant. The isolates were potential pathogens and resistant to multiple classes of antibiotics. Stethoscope is potential vehicle in the transmission of infections between patients and Healthcare Workers. Stethoscope diaphragm should be disinfected before and after each patient contact. PMID:24330702

Bacterial contamination, bacterial profile and antimicrobial susceptibility pattern of isolates from stethoscopes at Jimma University Specialized Hospital.

PubMed

Shiferaw, Teklu; Beyene, Getenet; Kassa, Tesfaye; Sewunet, Tsegaye

2013-12-13

Hospital acquired infections are recognized as critical public health problems. Infections are frequently caused by organisms residing in healthcare environment, including contaminated medical equipment like Stethoscopes. To determine bacterial contamination, bacterial profile and anti-microbial susceptibility pattern of the isolates from stethoscopes at Jimma University Specialized Hospital. Cross-sectional study conducted from May to September 2011 at Jimma University Specialized Hospital. One hundred seventy-six stethoscopes owned by Health Care Workers (HCWs) and Medical students were randomly selected and studied. Self-administered structured questionnaire was used to collect socio-demographic data. Specimen was collected using moisten sterile cotton swab and 1 ml normal saline was used to transport the specimen, all laboratory investigations were done following standard microbiological techniques, at Microbiology Laboratory, Jimma University. SPSS windows version 16 used for data analysis and P <0.05 was considered statistically significant. A total, of 151 (85.8%) stethoscopes were contaminated. A total of 256 bacterial strains and a mean of 1.44×104 CFUs/diaphragm of stethoscopes was isolated. Of the 256 isolates, 133 (52%) were potential pathogens like S. aureus, Klebsiella spp., Citrobacter spp., Salmonella spp., Proteus spp., Enterobacter spp., P. aeruginosa and E. coli. All strains were resistant to multiple classes of antibiotics (two to eight classes of antibiotics). Disinfection practice was poor. Disinfection practice was found to be associated with bacterial contamination of stethoscopes (P < 0.05). High contamination rate 100 (90.9%) was observed among stethoscopes that had never been disinfected; while the least contamination 29 (72.2%) was found on those disinfected a week or less before the survey. Bacterial contamination of the stethoscope was significant. The isolates were potential pathogens and resistant to multiple classes of antibiotics. Stethoscope is potential vehicle in the transmission of infections between patients and Healthcare Workers. Stethoscope diaphragm should be disinfected before and after each patient contact.

21 CFR 884.2900 - Fetal stethoscope.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Fetal stethoscope. (a) Identification. A fetal stethoscope is a device used for listening to fetal heart sounds. It is designed to transmit the fetal heart sounds not only through sound channels by air...

21 CFR 884.2900 - Fetal stethoscope.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Fetal stethoscope. (a) Identification. A fetal stethoscope is a device used for listening to fetal heart sounds. It is designed to transmit the fetal heart sounds not only through sound channels by air...

21 CFR 884.2900 - Fetal stethoscope.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Fetal stethoscope. (a) Identification. A fetal stethoscope is a device used for listening to fetal heart sounds. It is designed to transmit the fetal heart sounds not only through sound channels by air...

21 CFR 884.2900 - Fetal stethoscope.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Fetal stethoscope. (a) Identification. A fetal stethoscope is a device used for listening to fetal heart sounds. It is designed to transmit the fetal heart sounds not only through sound channels by air...

21 CFR 884.2900 - Fetal stethoscope.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Fetal stethoscope. (a) Identification. A fetal stethoscope is a device used for listening to fetal heart sounds. It is designed to transmit the fetal heart sounds not only through sound channels by air...

The stethoscope: some preliminary investigations.

PubMed

Welsby, P D; Parry, G; Smith, D

2003-12-01

Textbooks, clinicians, and medical teachers differ as to whether the stethoscope bell or diaphragm should be used for auscultating respiratory sounds at the chest wall. Logic and our results suggest that stethoscope diaphragms are more appropriate.

Bacterial contamination and stethoscope disinfection practices: a cross-sectional survey of healthcare workers in Karachi, Pakistan.

PubMed

Rao, Danish Ahmed; Aman, Aiysha; Muhammad Mubeen, Syed; Shah, Ahmed

2017-07-01

Stethoscopes routinely used for clinical examination of patients may potentially transfer micro-organisms and cause iatrogenic infections. This study was undertaken to detect the presence of microorganisms on stethoscopes used clinically in hospitals of Karachi, Pakistan and to ascertain the infection control practices of healthcare workers (HCWs). In a cross-sectional study, 118 samples were collected from public and private institutions. Samples were tested for the presence and sensitivity of pathogenic microorganisms. Microorganisms were found on diaphragms of 33/64 (51.6%) and 19/57 (33.3%) stethoscopes in public and private sector hospitals, respectively. Methycillin resistance was identified in all staphylococcally contaminated samples. Only 33 (18%) respondents reported cleaning their stethoscopes regularly. We highlight the need for more and better on-the-job routines for decontaminating stethoscopes among HCWs in Karachi.

Nursing Care Hour Standards Study. Part 2 thru Part 4

DTIC Science & Technology

1981-09-01

pulse area and record results. PULSE - APICAL: Place equipment at bedside, place stethoscope over .5 apex of heart and count rate, remove stethoscope ...equipment at bedside, assist physi- 2 cian with measurement, then remove equipment from area, HEART SOUNDS ASSESSMENT: Place stethoscope at bedside...Remove fingers from pulse area and record results. OR PULSE - APICAL: Place equipment at bedside, place stethoscope over apex of heart and count rate

On stethoscope design: a challenge for biomedical circuit designers.

PubMed

Hahn, A W

2001-01-01

Most clinicians learned the art and science of auscultation using an acoustic stethoscope. While many models of electronic stethoscopes have been marketed over the years, none of them seem to do a very good job of emulating the most common forms of acoustic stethoscopes available. This paper is an appeal to biomedical circuit designers to learn more about the acoustics of commonly used stethoscopes and to develop an appropriate group of circuits which would emulate them much like music synthesizers can emulate almost any musical instrument. The implications are for creative designers to move toward a rational and acceptable design for both personal physician use and for telemedicine.

The stethoscope: some preliminary investigations

PubMed Central

Welsby, P; Parry, G; Smith, D

2003-01-01

Textbooks, clinicians, and medical teachers differ as to whether the stethoscope bell or diaphragm should be used for auscultating respiratory sounds at the chest wall. Logic and our results suggest that stethoscope diaphragms are more appropriate. PMID:14707247

Evaluation of Thoracic Injury in Swine Model with a Noise Immune Stethoscope

DTIC Science & Technology

2011-04-01

USAARL Report No. 2011-16 Evaluation of Thoracic Injury in Swine Model with a Noise Immune Stethoscope By Alaistair Bushby Eric J. Ansorge Keith...Include area code) 22-04-2011 Final Evaluation of Thoracic Injury in Swine Model with a Noise Immune Stethoscope Alaistair Bushby Eric J. Ansorge...and to provide life saving interventions. This study evaluated the feasibility and sensitivity of a newly developed electronic stethoscope concept

Prevalence of methicillin-resistant Staphylococcus aureus on the stethoscopes of emergency medical services providers.

PubMed

Merlin, Mark A; Wong, Matthew L; Pryor, Peter W; Rynn, Kevin; Marques-Baptista, Andreia; Perritt, Rachael; Stanescu, Catherine G; Fallon, Timothy

2009-01-01

The investigation seeks to determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) on the stethoscopes of emergency medical services (EMS) providers. While stethoscopes are known fomites for MRSA, the prevalence of MRSA in the prehospital setting is not well documented in the literature. This was a prospective, observational cohort study of 50 stethoscopes provided by consecutive, consenting EMS providers at our academic emergency department (ED). Stethoscopes were swabbed with saline culture applicators and samples were cultured on a commercial MRSA test kit containing mannitol salt agar with oxacillin. After 72 hours of incubation at 37 degrees C, two emergency physicians and one microbiologist analyzed the plates independently. MRSA colonization was recorded as positive if all three reviewers agreed that colonization had occurred. Of 50 stethoscopes, 16 had MRSA colonization, and 16 (32%) EMS professionals had no recollection of when their stethoscopes had been cleaned last. Reported length of time since last cleaning was grouped into six categories: one to seven days, eight to 14 days, 15 to 30 days, 31 to 180 days, 181 days to 365 days, and unknown. The median time frame reported since the last cleaning was one to seven days. In the model, an increase from one time category to the next increased the odds of MRSA colonization by 1.86 (odds ratio = 1.86, p = 0.038). In this ED setting, MRSA was found on approximately one in three stethoscopes of EMS professionals. A longer length of time since the last stethoscope cleaning increased the odds of MRSA colonization.

Development of digital stethoscope for telemedicine.

PubMed

Lakhe, Aparna; Sodhi, Isha; Warrier, Jyothi; Sinha, Vineet

2016-01-01

The stethoscope is a medical acoustic device which is used to auscultate internal body sounds, mainly the heart and lungs. A digital stethoscope overcomes the limitations of a conventional stethoscope as the sound data is transformed into electrical signals which can be amplified, stored, replayed and, more importantly, sent for an expert opinion, making it very useful in telemedicine. With the above in view, a low cost digital stethoscope has been developed which is interfaceble with mobile communication devices. In this instrument sounds from various locations can be captured with the help of an electret condenser microphone. Captured sound is filtered, amplified and processed digitally using an adaptive line enhancement technique to obtain audible and distinct heart sounds.

Clinical Assessment of the Noise Immune Stethoscope aboard a U.S. Navy Carrier

DTIC Science & Technology

2011-11-01

Participants rated their confidence in the use of this device to detect heart /lung sounds compared to a traditional stethoscope . A Wilcoxin rank...Figure 15. Median ratings of confidence in the use of the device to detect pathologic heart /lung sounds compared to a traditional stethoscope in...intubation versus heart /lung sounds; figure 16). To assess the ease of use compared to a traditional stethoscope , one-sample Wilcoxin signed rank tests

A simulator-based study of in-flight auscultation.

PubMed

Tourtier, Jean-Pierre; Libert, Nicolas; Clapson, Patrick; Dubourdieu, Stéphane; Jost, Daniel; Tazarourte, Karim; Astaud, Cécil-Emmanuel; Debien, Bruno; Auroy, Yves

2014-04-01

The use of a stethoscope is essential to the delivery of continuous, supportive en route care during aeromedical evacuations. We compared the capability of 2 stethoscopes (electronic, Litmann 3000; conventional, Litmann Cardiology III) at detecting pathologic heart and lung sounds, aboard a C135, a medical transport aircraft. Sounds were mimicked using a mannequin-based simulator SimMan. Five practitioners examined the mannequin during a fly, with a variety of abnormalities as follows: crackles, wheezing, right and left lung silence, as well as systolic, diastolic, and Austin-Flint murmur. The comparison for diagnosis assessed (correct or wrong) between using the electronic and conventional stethoscopes were performed as a McNemar test. A total of 70 evaluations were performed. For cardiac sounds, diagnosis was right in 0/15 and 4/15 auscultations, respectively, with conventional and electronic stethoscopes (McNemar test, P = 0.13). For lung sounds, right diagnosis was found with conventional stethoscope in 10/20 auscultations versus 18/20 with electronic stethoscope (P = 0.013). Flight practitioners involved in aeromedical evacuation on C135 plane are more able to practice lung auscultation on a mannequin with this amplified stethoscope than with the traditional one. No benefit was found for heart sounds.

Ultrasound and stethoscope as tools in medical education and practice: considerations for the archives

PubMed Central

Fakoya, Francis A; du Plessis, Maira; Gbenimacho, Ikechi B

2016-01-01

Objectives In recent years, the use and portability of ultrasound has threatened the utility of the stethoscope, with many debating and even advocating its replacement. The authors set out to assess opinions in this regard among faculty within a medical school and specifically within an anatomy department where ultrasound is incorporated into the curriculum from the first term. Methods A debate was elicited during a biweekly Anatomy Journal Club session and was centered on three published papers presented. Several questions were raised regarding the possible replacement of stethoscope – the value of early exposure to students as well as how ultrasound and stethoscope should be considered by physicians, students, and teachers. Results The general consensus was that the stethoscope should not be replaced but should be used in conjunction with emerging portable ultrasound. Caution was given that technology could “overcomplicate” diagnosis and lead to increased tests resulting in increased cost of care. In terms of exposing students to ultrasound, just as the stethoscope requires practice to use effectively, so does the ultrasound and should be introduced as early on as possible. As is the case with the stethoscope, students may not initially appreciate all the finer details on ultrasound; however, continual use would improve skill. Conclusion The stethoscope should always remain part of the physical examination and ultrasound should be used in addition to, not replacement of. As technology advances the need for apprenticeship, training increases and students of the medical profession should be exposed to these technologies as early as possible. Hence, it is not yet time to archive the stethoscope. Perhaps never. PMID:27471420

Factors influencing stethoscope cleanliness among clinical medical students.

PubMed

Saunders, C; Hryhorskyj, L; Skinner, J

2013-07-01

This study aims to identify current stethoscope hygiene habits and attitudes in a UK medical school setting. Students completed a questionnaire using Likert-scale questions and free-text answers. A total of 308 questionnaires were completed from a potential 750 students (41%); 22.4% of respondents had never cleaned their stethoscope and only 3.9% cleaned their stethoscope after every patient. Significant correlations were identified between cleaning frequency and: others acting as role models (P = 0.001), students having confidence in how to clean stethoscopes (P = 0.001), and students thinking cleaning was important (P = 0.01), thereby highlighting inadequate education and role models as potential problems. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

What's growing on General Practitioner's stethoscope?

PubMed

Carducci, A; Cargnelutti, M; Tassinari, F; Bizzarro, A; Cordio, G; Carletti, S; Maccarini, L; Pelissero, G

2016-01-01

Non-critical medical devices, as stethoscopes, have long been considered as vectors in microorganisms' transmission. Cleaning standards for non-critical medical equipment are often unclear. This study was designed to assess the attitude of General Practitioners (GPs) towards cleaning their stethoscope and the degree of microbiological contamination of doctor's instrument in outpatient setting. Observational, crossover study. A structured questionnaire was administered to GPs to test their knowledge about medical instrument's cleanliness recommendations and the surface of the diaphragm of their stethoscopes was analyzed for bacteriological isolates using mass spectrometry technique. Most of GPs declared they don't know cleaning recommendations for non-critical medical devices and a relevant bacterial growth was identified on the majority of the stethoscopes' membranes. Almost all microbiological isolates resulted typically found in cutaneous flora. We can't state that the GP's stethoscopes feature a risk of transmission for microbiological pathogens; anyway, because of the level of contamination we observed, cleaning recommendations to disinfect instruments on a regular basis should be better indicated.

Stethoscopes as a source of hospital-acquired methicillin-resistant Staphylococcus aureus.

PubMed

Russell, Abigail; Secrest, Janet; Schreeder, Carolyn

2012-04-01

Stethoscopes are potential vectors of methicillin-resistant Staphylococcus aureus (MRSA). The purpose of this project was to determine the presence of MRSA on the diaphragms of personal and unit stethoscopes within a hospital setting before and after cleaning with alcohol prep pads. The sample consisted of 141 personal and unit stethoscopes in adult medical-surgical and intensive care units of a large university hospital in the Southeast. Each stethoscope was cultured once before cleaning and once after cleaning. Cultures were obtained using sterile swabs and inoculated on a selective medium for MRSA. Bacterial growth was noted in the precleaning group, but no MRSA colonies were detected. The postcleaning group had no bacterial growth. There was not enough data to statistically support that isopropyl alcohol is effective in decreasing bacterial counts; however, these findings suggest that current disinfection guidelines are effective in preventing MRSA colonization on stethoscopes in this setting. Copyright © 2012 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.

Tele-auscultation support system with mixed reality navigation.

PubMed

Hori, Kenta; Uchida, Yusuke; Kan, Tsukasa; Minami, Maya; Naito, Chisako; Kuroda, Tomohiro; Takahashi, Hideya; Ando, Masahiko; Kawamura, Takashi; Kume, Naoto; Okamoto, Kazuya; Takemura, Tadamasa; Yoshihara, Hiroyuki

2013-01-01

The aim of this research is to develop an information support system for tele-auscultation. In auscultation, a doctor requires to understand condition of applying a stethoscope, in addition to auscultatory sounds. The proposed system includes intuitive navigation system of stethoscope operation, in addition to conventional audio streaming system of auscultatory sounds and conventional video conferencing system for telecommunication. Mixed reality technology is applied for intuitive navigation of the stethoscope. Information, such as position, contact condition and breath, is overlaid on a view of the patient's chest. The contact condition of the stethoscope is measured by e-textile contact sensors. The breath is measured by a band type breath sensor. In a simulated tele-auscultation experiment, the stethoscope with the contact sensors and the breath sensor were evaluated. The results show that the presentation of the contact condition was not understandable enough for navigating the stethoscope handling. The time series of the breath phases was usable for the remote doctor to understand the breath condition of the patient.

Digital stethoscope as an innovative tool on the teaching of auscultatory skills.

PubMed

Mesquita, Claudio Tinoco; Reis, Jader Costa dos; Simões, Luciana Silveira; Moura, Eduardo Cardoso de; Rodrigues, Gustavo Amarante; Athayde, Carolina Cunto de; Machado, Hugo Lima; Lanzieri, Pedro Gemal

2013-02-01

Physical cardiovascular examination, particularly cardiac auscultation, is one of the most difficult clinical skills for students during their medical training. Studies suggest that the use of technologies such as digital stethoscope increase the accuracy of clinical examination, however, its impact on the teaching of cardiac auscultation for undergraduate students of medicine is not known. The objective is to demonstrate the usefulness of the digital stethoscope compared to traditional methods as a tool in the teaching of auscultatory skills. nterventional, longitudinal, controlled, unicenter and randomized study. Thirty-eight medicine students were enrolled for a cardiovascular semiology course lasting eight weeks. The course program included lectures and bedside practice in Cardiology wards. In the practical lessons, the students were randomized into two groups: 1) (n = 21) digital stethoscope (Littmann® Model 3200, 3M); and 2) (n = 17) conventional stethoscopes. A pre-training evaluation was conducted through a test using the software Heart Sounds®, which was repeated after the course. The average scores were compared by paired T test and unpaired T test. It is observed that, at the end of the course, there was a significantly greater improvement in the group that used the digital stethoscope (51.9%) compared to the group using the conventional stethoscope (29.5%). Short-term interventions for cardiac semiology teaching are able to contribute significantly to improving proficiency in the identification of heart sounds. The use of digital stethoscope proved to be a positive factor in teaching these skills.

In flight auscultation: comparison of electronic and conventional stethoscopes.

PubMed

Tourtier, Jean P; Fontaine, Emmamuelle; Coste, Sébastien; Ramsang, Solange; Schiano, Patrick; Viaggi, Marie; Libert, Nicolas; Durand, Xavier; Chargari, Cyrus; Borne, Marc

2011-10-01

The ability to auscultate during air medical transport is compromised by high ambient noise levels. The aim of this study was to assess the capabilities of a traditional and an amplified stethoscope (which is expected to reduce background and ambient noise) to assess heart and breath sounds during medical transport in a Falcon 50 plane. A prospective, double-blind, randomized study was performed. We tested 1 model of traditional stethoscope (Littman cardiology III) and 1 model of amplified stethoscope (Littman 3100). We studied heart and lung auscultation during real medical evacuations aboard Falcon 50 (medically configured). For each, the quality of auscultation was described using a numeric rating scale (ranging from 0 to 10, with 0 corresponding to "I hear nothing" and 10 corresponding to "I hear perfectly"). Comparisons were accomplished using a t test for paired values. A total of 32 comparative evaluations were performed. For cardiac auscultation, the value of the rating scale was 5.8 ± 1.5 and 6.4 ± 1.9, respectively, for the traditional and amplified stethoscope (P = .018). For lung sounds, quality of auscultation was estimated at 3.3 ± 2.4 for traditional stethoscope and at 3.7 ± 2.9 for amplified stethoscope (P = .15). Practicians in Falcon 50 are more able to hear cardiac sounds with an amplified than with a traditional stethoscope, whereas there is no significant difference concerning breath sounds auscultation. Copyright © 2011 Elsevier Inc. All rights reserved.

Predictors of stethoscope disinfection among pediatric health care providers.

PubMed

Muniz, Jeanette; Sethi, Rosh K V; Zaghi, Justin; Ziniel, Sonja I; Sandora, Thomas J

2012-12-01

Stethoscopes are contaminated with bacteria, but predictors of stethoscope disinfection frequency are unknown. We sought to describe health care provider stethoscope disinfection attitudes and practices and determine predictors of frequent disinfection. We used an anonymous online survey of nurses, nurse practitioners, and physicians at a pediatric hospital. We assessed frequency and methods of disinfection, perceptions of contamination, and barriers to disinfection. Multivariate logistic regression models were used to identify independent predictors of disinfecting after every use. One thousand four hundred one respondents completed the survey: 76% believed that infection transmission occurs via stethoscopes, but only 24% reported disinfecting after every use. In multivariate analyses, belief that infection transmission occurs via stethoscopes significantly increased the odds of disinfection after every use (odds ratio [OR], 2.06 [95% confidence interval (CI): 1.38-3.06]). The odds of disinfection after every use were significantly decreased in those who perceived the following barriers: lack of time (OR, 0.31 [95% CI: 0.18-0.54]), lack of access to disinfection material (OR, 0.41 [95% CI: 0.29-0.57]), or lack of visual reminders to disinfect (OR, 0.22 [95% CI: 0.14-0.34]). Only a minority of pediatric health care providers reported disinfecting their stethoscopes after every use. Increasing access to disinfection materials and visual reminders in health care facilities may improve stethoscope disinfection practices. Copyright © 2012 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Stethoscopes as potential intrahospital carriers of pathogenic microorganisms.

PubMed

Campos-Murguía, Alejandro; León-Lara, Ximena; Muñoz, Juan M; Macías, Alejandro E; Alvarez, José A

2014-01-01

Stethoscopes can take part in the transmission of health care-associated infections. We cultured 112 stethoscopes by direct imprint on blood agar to estimate the prevalence of potentially pathogenic microorganisms. Forty-eight (47%) produced 50 potentially pathogenic microorganisms; from these, 43 (86%) were Staphylococcus aureus, of which 18 (42%) were methicillin-resistant S. aureus. We concluded that stethoscopes should be considered as potential fomites and must be disinfected routinely before and after each patient contact. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Digital stethoscope: technology update.

PubMed

Swarup, Supreeya; Makaryus, Amgad N

2018-01-01

Cardiovascular disease (CVD) is recognized as the leading cause of mortality throughout the world. About one-third of global mortality is attributable to CVD. In addition to clinical presentation, specific clinical exam findings can assist in treating and preventing CVD. CVD may initially manifest as pulmonary pathology, and thus, accurate cardiopulmonary auscultation is paramount to establishing accurate diagnosis. One of the most powerful tools available to physicians is the stethoscope. The stethoscope first emerged in the year 1818, invented by a French physician, René Laennec. Since then, the initial modest monaural wooden tube has evolved into a sophisticated digital device. This paper provides an analysis of the evolution of the stethoscope as well as highlights the advancement made by the modern digital stethoscope including the application of this tool in advancing care for patients suffering from CVD.

Bacterial contamination of stethoscope chest pieces and the effect of daily cleaning.

PubMed

Fujita, H; Hansen, B; Hanel, R

2013-01-01

Stethoscopes are a potential source of nosocomial infection for hospitalized humans, a phenomenon not previously studied in companion animals. To determine if daily cleaning of stethoscope chest pieces reduces bacterial contamination between cleanings. Client-owned dogs and cats. Prospective observational study. In phase 1, bacterial cultures were obtained from the chest pieces of 10 participant stethoscopes once weekly for 3 weeks. In phase 2, stethoscopes were cleaned daily and 2 culture samples were obtained once weekly, immediately before and after cleaning with 70% isopropyl alcohol, for 3 weeks. Daily cleaning eliminated bacteria immediately after each cleaning (P = .004), but did not reduce the rate of positive cultures obtained before cleaning in phase 2. Cultures were positive for 20/30 (67%) samples during phase 1 and 18/30 (60%) obtained before daily cleaning during phase 2. Recovered organisms included normal skin flora, agents of opportunistic infections, and potential pathogens. The only genus that was repeatedly recovered from the same stethoscope for 2 or more consecutive weeks was Bacillus sp. Daily cleaning was highly effective at removing bacteria, but provided no reduction in precleaning contamination. Cleaning stethoscopes after use on dogs or cats infected with pathogenic bacteria and before use on immunocompromised animals should be considered. Copyright © 2013 by the American College of Veterinary Internal Medicine.

Are Simulation Stethoscopes a Useful Adjunct for Emergency Residents' Training on High-fidelity Mannequins?

PubMed

Warrington, Steven J; Beeson, Michael S; Fire, Frank L

2013-05-01

Emergency medicine residents use simulation training for many reasons, such as gaining experience with critically ill patients and becoming familiar with disease processes. Residents frequently criticize simulation training using current high-fidelity mannequins due to the poor quality of physical exam findings present, such as auscultatory findings, as it may lead them down an alternate diagnostic or therapeutic pathway. Recently wireless remote programmed stethoscopes (simulation stethoscopes) have been developed that allow wireless transmission of any sound to a stethoscope receiver, which improves the fidelity of a physical examination and the simulation case. Following institutional review committee approval, 14 PGY1-3 emergency medicine residents were assessed during 2 simulation-based cases using pre-defined scoring anchors on multiple actions, such as communication skills and treatment decisions (Appendix 1). Each case involved a patient presenting with dyspnea requiring management based off physical examination findings. One case was a patient with exacerbation of heart failure, while the other was a patient with a tension pneumothorax. Each resident was randomized into a case associated with the simulation stethoscope. Following the cases residents were asked to fill out an evaluation questionnaire. Residents perceived the most realistic physical exam findings on those associated with the case using the simulation stethoscope (13/14, 93%). Residents also preferred the simulation stethoscope as an adjunct to the case (13/14, 93%), and they rated the simulation stethoscope case to have significantly more realistic auscultatory findings (4.4/5 vs. 3.0/5 difference of means 1.4, p=0.0007). Average scores of residents were significantly better in the simulation stethoscope-associated case (2.5/3 vs. 2.3/3 difference of means 0.2, p=0.04). There was no considerable difference in the total time taken per case. A simulation stethoscope may be a useful adjunct to current emergency medicine simulation-based training. Residents both preferred the use of the simulation stethoscope and perceived physical exam findings to be more realistic, leading to improved fidelity. Potential sources of bias include the small population, narrow scoring range, and the lack of blinding. Further research, focusing on use for resident assessment and clinical significance with a larger population and blinding of graders, is needed.

Are Simulation Stethoscopes a Useful Adjunct for Emergency Residents' Training on High-fidelity Mannequins?

PubMed Central

Beeson, Michael S.; Fire, Frank L.

2013-01-01

Introduction: Emergency medicine residents use simulation training for many reasons, such as gaining experience with critically ill patients and becoming familiar with disease processes. Residents frequently criticize simulation training using current high-fidelity mannequins due to the poor quality of physical exam findings present, such as auscultatory findings, as it may lead them down an alternate diagnostic or therapeutic pathway. Recently wireless remote programmed stethoscopes (simulation stethoscopes) have been developed that allow wireless transmission of any sound to a stethoscope receiver, which improves the fidelity of a physical examination and the simulation case. Methods: Following institutional review committee approval, 14 PGY1-3 emergency medicine residents were assessed during 2 simulation-based cases using pre-defined scoring anchors on multiple actions, such as communication skills and treatment decisions (Appendix 1). Each case involved a patient presenting with dyspnea requiring management based off physical examination findings. One case was a patient with exacerbation of heart failure, while the other was a patient with a tension pneumothorax. Each resident was randomized into a case associated with the simulation stethoscope. Following the cases residents were asked to fill out an evaluation questionnaire. Results: Residents perceived the most realistic physical exam findings on those associated with the case using the simulation stethoscope (13/14, 93%). Residents also preferred the simulation stethoscope as an adjunct to the case (13/14, 93%), and they rated the simulation stethoscope case to have significantly more realistic auscultatory findings (4.4/5 vs. 3.0/5 difference of means 1.4, p=0.0007). Average scores of residents were significantly better in the simulation stethoscope-associated case (2.5/3 vs. 2.3/3 difference of means 0.2, p=0.04). There was no considerable difference in the total time taken per case. Conclusion: A simulation stethoscope may be a useful adjunct to current emergency medicine simulation-based training. Residents both preferred the use of the simulation stethoscope and perceived physical exam findings to be more realistic, leading to improved fidelity. Potential sources of bias include the small population, narrow scoring range, and the lack of blinding. Further research, focusing on use for resident assessment and clinical significance with a larger population and blinding of graders, is needed. PMID:23687548

Antimicrobial copper alloys decreased bacteria on stethoscope surfaces.

PubMed

Schmidt, Michael G; Tuuri, Rachel E; Dharsee, Arif; Attaway, Hubert H; Fairey, Sarah E; Borg, Keith T; Salgado, Cassandra D; Hirsch, Bruce E

2017-06-01

Stethoscopes may serve as vehicles for transmission of bacteria among patients. The aim of this study was to assess the efficacy of antimicrobial copper surfaces to reduce the bacterial concentration associated with stethoscope surfaces. A structured prospective trial involving 21 health care providers was conducted at a pediatric emergency division (ED) (n = 14) and an adult medical intensive care unit located in tertiary care facilities (n = 7). Four surfaces common to a stethoscope and a facsimile instrument fabricated from U.S. Environmental Protection Agency-registered antimicrobial copper alloys (AMCus) were assessed for total aerobic colony counts (ACCs), methicillin-resistant Staphylococcus aureus, gram-negative bacteria, and vancomycin-resistant enterococci for 90 days. The mean ACCs collectively recovered from all stethoscope surfaces fabricated from the AMCus were found to carry significantly lower concentrations of bacteria (pediatric ED, 11.7 vs 127.1 colony forming units [CFU]/cm 2 , P < .00001) than their control equivalents. This observation was independent of health care provider or infection control practices. Absence of recovery of bacteria from the AMCu surfaces (66.3%) was significantly higher (P < .00001) than the control surfaces (22.4%). The urethane rim common to the stethoscopes was the most heavily burdened surface; mean concentrations exceeded the health care-associated infection acquisition concentration (5 CFU/cm 2 ) by at least 25×, supporting that the stethoscope warrants consideration in plans mitigating microbial cross-transmission during patient care. Stethoscope surfaces fabricated with AMCus were consistently found to harbor fewer bacteria. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Comparing the auscultatory accuracy of health care professionals using three different brands of stethoscopes on a simulator

PubMed Central

Mehmood, Mansoor; Abu Grara, Hazem L; Stewart, Joshua S; Khasawneh, Faisal A

2014-01-01

Background It is considered standard practice to use disposable or patient-dedicated stethoscopes to prevent cross-contamination between patients in contact precautions and others in their vicinity. The literature offers very little information regarding the quality of currently used stethoscopes. This study assessed the fidelity with which acoustics were perceived by a broad range of health care professionals using three brands of stethoscopes. Methods This prospective study used a simulation center and volunteer health care professionals to test the sound quality offered by three brands of commonly used stethoscopes. The volunteer’s proficiency in identifying five basic ausculatory sounds (wheezing, stridor, crackles, holosystolic murmur, and hyperdynamic bowel sounds) was tested, as well. Results A total of 84 health care professionals (ten attending physicians, 35 resident physicians, and 39 intensive care unit [ICU] nurses) participated in the study. The higher-end stethoscope was more reliable than lower-end stethoscopes in facilitating the diagnosis of the auscultatory sounds, especially stridor and crackles. Our volunteers detected all tested sounds correctly in about 69% of cases. As expected, attending physicians performed the best, followed by resident physicians and subsequently ICU nurses. Neither years of experience nor background noise seemed to affect performance. Postgraduate training continues to offer very little to improve our trainees’ auscultation skills. Conclusion The results of this study indicate that using low-end stethoscopes to care for patients in contact precautions could compromise identifying important auscultatory findings. Furthermore, there continues to be an opportunity to improve our physicians and ICU nurses’ auscultation skills. PMID:25152636

Clinical evaluation of stethoscope-guided inflation of tracheal tube cuffs.

PubMed

Kumar, R D C; Hirsch, N P

2011-11-01

Tracheal tube cuffs are commonly inflated to pressures exceeding the recommended upper limit of 30 cmH(2)O. We evaluated whether a stethoscope-guided method of cuff inflation results in pressures within the recommended range. Patients were randomly assigned to receive one of two methods of cuff inflation. In the standard 'just seal' group, air was introduced into the tracheal cuff until the audible leak at the mouth disappeared. In the stethoscope-guided group, air was introduced into the cuff until a change from harsh to soft breath sounds occurred, whilst listening with a stethoscope bell placed over the thyroid cartilage. Twenty-five patients were recruited to each group. The median (IQR [range]) cuff pressure in the 'just seal' group was 34 (28-40 [18-49]) cmH(2)O, and in the stethoscope-guided group was 20 (20-26 [16-28]) cmH(2)O, p < 0.0001. The stethoscope-guided method of tracheal tube cuff inflation is a novel, simple technique that reliably results in acceptable tracheal cuff pressures. © 2011 The Authors. Anaesthesia © 2011 The Association of Anaesthetists of Great Britain and Ireland.

Digital stethoscope: technology update

PubMed Central

Swarup, Supreeya; Makaryus, Amgad N

2018-01-01

Cardiovascular disease (CVD) is recognized as the leading cause of mortality throughout the world. About one-third of global mortality is attributable to CVD. In addition to clinical presentation, specific clinical exam findings can assist in treating and preventing CVD. CVD may initially manifest as pulmonary pathology, and thus, accurate cardiopulmonary auscultation is paramount to establishing accurate diagnosis. One of the most powerful tools available to physicians is the stethoscope. The stethoscope first emerged in the year 1818, invented by a French physician, René Laennec. Since then, the initial modest monaural wooden tube has evolved into a sophisticated digital device. This paper provides an analysis of the evolution of the stethoscope as well as highlights the advancement made by the modern digital stethoscope including the application of this tool in advancing care for patients suffering from CVD. PMID:29379321

Aerobic Bacteria in the Diaphragmatic Portion of Stethoscope of Medical Professionals of Tertiary Care Hospital.

PubMed

Bham, G; Bhandari, J; Neupane, M R; Dawadi, R; Pradhan, P

2015-01-01

Hospital environment is a reservoir of wide varieties of microorganisms which are frequently reported colonizing in medical equipment. Stethoscopes are essential tools and of universal use in the medical profession, which might be a source of spreading nosocomial infections. This research project was conducted with an aim to assess the presence of aerobic bacteria in the stethoscope of the medical doctors working at Patan Hospital and students of Patan Academy of Health Sciences. It is a cross sectional study based on structured questionnaire and sample assessment from the stethoscope of doctors and students of Patan Hospital and Patan Academy of Health Sciences. The stethescopes used by the doctors of five major departments of Patan Hospital and students of clinical years were included in this study. Total of 99 stethoscope owned by different level of professionals (positions) and different departments were examined for bacterial contamination. Out of them, 36 were found to be considerably contaminated. Single strain of bacteria was grown from a single stethoscope. Among them 34 were Gram positive and remaining were Gram negative. Out of 34 gram postive bacteria, 29 were identified as Staphylococcus aureus, six were identified as Coagulase Negative Staphylococcus and remaining were Gram positive bacilli. There is presence of aerobic bacteria in diaphragmatic portion of stethoscope of medical professional of which the gram positives were the commonest.

The stethoscope - A 200th anniversary.

PubMed

Permin, Henrik; Norn, Svend

René T.H. Laënnec was the man who designed the first monaural instrument for mediate auscultation. The invention became a medical breakthrough. An instrument capable of enhancing the subtle sounds created by the human heart and lungs. This evolutionary instrument also had the benefit of decreasing the oftentim s too direct bodily contact between the doctor and the patient. Laënnec carefully described the different sounds created by the human organs and attempted to link them to the post mortem findings. Even though many doctors were enthusiastic regarding this new medical breakthrough, the stethoscope also had its opponents, but John Forbes' English translation of Laënnec's De l'auscultation midiate as well as William Stokes' treatise on the use of the stethoscope spread the news to the medical world. In Denmark the stethoscope was introduced by Oluf Lundt Bang, S.M. Trier and E. Hornemann. The next step forward was the develop- ment of the binaural stethoscope by G.P. Camman in New York. The Littmann Electronic Stethoscope (3M Health Care) created by David Littmann is considered the leading product globally in this medical field. Digitization, ultrasound and Doppler effect, as well as 2D and 3D printing, are evidence of an on-going evolution within this field of medical equipment as we get ready to celebrate the stethoscopes 200th anniversary.

A comparative study of electronic stethoscopes for cardiac auscultation.

PubMed

Pinto, C; Pereira, D; Ferreira-Coimbra, J; Portugues, J; Gama, V; Coimbra, M

2017-07-01

There are several electronic stethoscopes available on the market today, with a very high potential for healthcare namely telemedicine, assisted decision and education. However, there are no recent comparatives studies published about the recording quality of auscultation sounds. In this study we aim to: a) define a ranking, according to experts opinion of 6 of the most relevant electronic stethoscopes on the market today; b) verify if there are any relations between a stethoscope's performance and the type of pathology present; c) analyze if some pathologies are more easily identified than others when using electronic auscultation. Our methodology consisted in creating two study groups: the first group included 18 cardiologists and cardiology house officers, acting as the gold standard of this work. The second included 30 medical students. Using a database of heart sounds recorded in real hospital environments, we applied questionnaires to observers from each group. The first group listened to 60 cardiac auscultations recorded by the 6 stethoscopes, and each one was asked to identify the pathological sound present: aortic stenosis, mitral regurgitation or normal. The second group was asked to choose, between two auscultation recordings, using as criteria the best sound quality for the identification of pathological sounds. Results include a total of 1080 evaluations, in which 72% of cases were correctly diagnosed. A detailed breakdown of these results is presented in this paper. As conclusions, results showed that the impact of the differences between stethoscopes is very small, given that we did not find statistically significant differences between all pairs of stethoscopes. Normal sounds showed to be easier to identify than pathological sounds, but we did not find differences between stethoscopes in this identification.

The stethoscope in the Emergency Department: a vector of infection?

PubMed Central

Núñez, S.; Moreno, A.; Green, K.; Villar, J.

2000-01-01

The purposes of this study were to determine whether microorganisms can be isolated from the membranes of stethoscopes used by clinicians and nurses, and to analyse whether or not the degree of bacterial colonization could be reduced with different cleaning methods. We designed a transversal before-after study in which 122 stethoscopes were examined. Coagulase negative staphylococci (which are also potentially pathogenic microorganisms) were isolated together with 13 other potentially pathogenic microorganisms, including S. aureus, Acinetobacter sp. and Enterobacter agglomerans. The most effective antiseptic was propyl alcohol. Analysis of the cleaning habits of the Emergency Department (ED) staff, showed that 45% cleaned the stethoscope annually or never. The isolation of potentially pathogenic microorganisms suggests that the stethoscope must be considered as a potential vector of infection not only in the ED but also in other hospital wards and out-patient clinics. PMID:10813148

Validation of an effective, low cost, Free/open access 3D-printed stethoscope

PubMed Central

Pavlosky, Alexander; Glauche, Jennifer; Chambers, Spencer; Al-Alawi, Mahmoud; Yanev, Kliment

2018-01-01

The modern acoustic stethoscope is a useful clinical tool used to detect subtle, pathological changes in cardiac, pulmonary and vascular sounds. Currently, brand-name stethoscopes are expensive despite limited innovations in design or fabrication in recent decades. Consequently, the high cost of high quality, brand name models serves as a barrier to clinicians practicing in various settings, especially in low- and middle-income countries. In this publication, we describe the design and validation of a low-cost open-access (Free/Libre) 3D-printed stethoscope which is comparable to the Littmann Cardiology III for use in low-access clinics. PMID:29538426

The electronic stethoscope.

PubMed

Leng, Shuang; Tan, Ru San; Chai, Kevin Tshun Chuan; Wang, Chao; Ghista, Dhanjoo; Zhong, Liang

2015-07-10

Most heart diseases are associated with and reflected by the sounds that the heart produces. Heart auscultation, defined as listening to the heart sound, has been a very important method for the early diagnosis of cardiac dysfunction. Traditional auscultation requires substantial clinical experience and good listening skills. The emergence of the electronic stethoscope has paved the way for a new field of computer-aided auscultation. This article provides an in-depth study of (1) the electronic stethoscope technology, and (2) the methodology for diagnosis of cardiac disorders based on computer-aided auscultation. The paper is based on a comprehensive review of (1) literature articles, (2) market (state-of-the-art) products, and (3) smartphone stethoscope apps. It covers in depth every key component of the computer-aided system with electronic stethoscope, from sensor design, front-end circuitry, denoising algorithm, heart sound segmentation, to the final machine learning techniques. Our intent is to provide an informative and illustrative presentation of the electronic stethoscope, which is valuable and beneficial to academics, researchers and engineers in the technical field, as well as to medical professionals to facilitate its use clinically. The paper provides the technological and medical basis for the development and commercialization of a real-time integrated heart sound detection, acquisition and quantification system.

In-flight auscultation during medical air evacuation: comparison between traditional and amplified stethoscopes.

PubMed

Fontaine, Emmanuelle; Coste, Sébastien; Poyat, Chrystelle; Klein, Céline; Lefort, Hugues; Leclerc, Thomas; Dubourdieu, Stéphane; Briche, Frédérique; Jost, Daniel; Maurin, Olga; Domanski, Laurent; Tourtier, Jean-Pierre

2014-01-01

The aim of this study was to evaluate the capacity of a traditional stethoscope versus an electronically amplified one (expected to reduce background and ambient noise) to assess heart and respiratory sounds during medical transport. It was a prospective, double-blinded, randomized performed study. One traditional stethoscope (Littmann Cardiology III; 3M, St Paul, MN) and 1 electronically amplified stethoscope (Littmann 3200, 3M) were used for our tests. Heart and lung auscultation during real medical evacuations aboard a medically configured Falcon 50 aircrafts were studied. The quality of auscultation was ranged using a numeric rating scale from 0 to 10 (0 corresponding to "I hear nothing" and 10 to "I hear perfectly"). Data collected were compared using a t-test for paired values. A total of 40 comparative evaluations were performed. For cardiac auscultation, the value of the rating scale was 4.53 ± 1.91 and 7.18 ± 1.88 for the traditional and amplified stethoscope, respectively (paired t-test: P < .0001). For respiratory sounds, quality of auscultation was estimated at 3.1 ± 1.95 for a traditional stethoscope and 5.10 ± 2.13 for the amplified one (paired t-test: P < .0001). This study showed that practitioners would be better helped in hearing cardiac and respiratory sounds with an electronically amplified stethoscope than with a traditional one during air medical transport in a medically configured Falcon 50 aircraft. Copyright © 2014 Air Medical Journal Associates. Published by Elsevier Inc. All rights reserved.

Vibro-acoustic model of a piezoelectric-based stethoscope for chest sound measurements

NASA Astrophysics Data System (ADS)

Nelson, G.; Rajamani, R.; Erdman, A.

2015-09-01

This article focuses on the influence of noise and vibration on chest sound measurements with a piezoelectric stethoscope. Two types of vibrations, namely inputs through the patient chest and disturbances from the physician, influence the acoustic measurement. The goal of this work is to develop a model to understand the propagation of these vibrational noises through the stethoscope and to the piezoelectric sensing element. Using the model, methods to reduce the influence of disturbances acting on the stethoscope from the physician handling the device are explored. A multi-DOF rigid body vibration model consisting of discrete connected components is developed for the piezoelectric stethoscope. Using a two-port lumped parameter model, the mechanical vibrations are related to the resulting electrical signal. The parameterized state space model is experimentally validated and its parameters are identified by using a thorax simulator and vibration shaker. Based on predictions from the model, the introduction of vibration isolation to reduce the influence of physician noise on the transducer is then pursued. It is shown that direct vibration isolation between the transducer and the rest of the stethoscope structure leads to a reduction in coupling with the patient’s chest. However, if isolation is instead introduced between the transducer housing and the rest of the stethoscope, then vibration isolation from the physician is achieved with far less reduction in patient coupling. Experimental results are presented to study the influence of the proposed design changes and confirm the predicted model behavior.

A new UV-LED device for automatic disinfection of stethoscope membranes.

PubMed

Messina, Gabriele; Burgassi, Sandra; Messina, Daniele; Montagnani, Valerio; Cevenini, Gabriele

2015-10-01

Stethoscopes are widely used by doctors and nurses. Poor stethoscope hygiene is a potential source of nosocomial infection. This study aimed to propose an innovative solution, based on the latest advances in ultraviolet (UV) light-emitting diodes (LEDs), for disinfecting stethoscope membranes automatically and efficiently. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis were sown on 28 stethoscope membranes and then transferred to Petri dishes. Treatment involved illuminating exposed Petri dishes with a UVC LED for 1 minute. For each microbe, the number of colony-forming units (cfu) at 36°C was compared in control and treated dishes using the Wilcoxon signed-rank test. The Kruskal-Wallis test was used to assess percent reductions in bacteria. Statistical significance was set at 99%. A significant reduction in cfu counts after UV treatment (P < .01) was found for all bacteria: 85.5% for E faecalis, 87.5% for S aureus, 94.3% for E coli, and 94.9% for P aeruginosa . No significant differences in percent reduction in cfu were found between bacteria (P > .01). The stethoscope, symbol of medicine and health care professionals, has been demonstrated to be a carrier of microorganisms. The treatment technique was effective and efficient in disinfecting the membranes. These promising results represent a step forward toward eliminating stethoscope membrane contamination with an innovative approach. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

A Dual-Mode Noise-Immune Stethoscope for Use in Noisy Vehicles

DTIC Science & Technology

2006-11-01

inside helicopters, fixed-wing aircraft, or ambulances where noise levels preclude auscultation with standard stethoscopes. With- out this...The use of an ultrasound transmitter and receiver, however, provides an essentially noise-free auscultation channel since transportation vehicles do...broadband noise fields of intensities as high as 120 dB. A hybrid stethoscope has been developed that allows auscultation by ultrasound Doppler as well

USAARL Annual Progress Report Fiscal Year 2012

DTIC Science & Technology

2013-04-01

analyzed. A technical report is currently in progress. A research project entitled “Clinical Assessment of the Noise Immune Stethoscope ” evaluated the...noise immune stethoscope (NIS), a dual mode electronic and Doppler device, at Madigan Army Medical Center. Insight from the evaluations, data...Immune Stethoscope aboard a U.S. Navy Carrier. (Report No. 2012-02). Fort Rucker, AL: U.S. Army Aeromedical Research Laboratory. Gordon, E., & Reeves

Assessment of the Noise Immune Stethoscope in a Clinical Environment

DTIC Science & Technology

2014-03-01

compared to using a traditional stethoscope . Anecdotal feedback from the clinicians indicated that sounds from the heart and related cardiothoracic...same technology as widely available fetal heart rate monitors for the consumer market. Comparable to other devices that combine acoustic and Doppler...understand Doppler” Congestive heart failure “able to hear crackles” Aortic stenosis “similar to traditional stethoscope , able to hear flows across

Integrating a Hand Held computer and Stethoscope into a Fetal Monitor

PubMed Central

Ahmad Soltani, Mitra

2009-01-01

This article presents procedures for modifying a hand held computer or personal digital assistant (PDA) into a versatile device functioning as an electronic stethoscope for fetal monitoring. Along with functioning as an electronic stethoscope, a PDA can provide a useful information source for a medical trainee. Feedback from medical students, residents and interns suggests the device is well accepted by medical trainees. PMID:20165517

Digital stethoscope system: the feasibility of cardiac auscultation

NASA Astrophysics Data System (ADS)

Pariaszewska, Katarzyna; Młyńczak, Marcel; Niewiadomski, Wiktor; Cybulski, Gerard

2013-10-01

The application of the digital stethoscope system is a new tendency in methods of cardiac auscultation. Heart sounds, generated by the fluctuations of blood velocity and vibrations of muscle structure, are an important signal in the primary diagnosis of heart diseases. Since the XIXs century for physical examination an analog stethoscope was used, but the development of microelectronics enable the construction of digital stethoscopes which started modern phonocardiography. The typical hardware of the system could be divided into analog and digital parts, respectively. The first one consists of microphone and pre-amplifier. The second one contains a microcontroller with peripherals for data saving and transmission. Usually the specialized software is applied for the signal acquisition and digital signal processing (filtering, spectral analysis and others). This paper presents an overview of methods used in cardiac auscultation and expected developing path in the future. It also contains the description of our digital stethoscope system, which is planned to be used in poliphysiographical studies.

Cardiac auscultation training of medical students: a comparison of electronic sensor-based and acoustic stethoscopes

PubMed Central

Høyte, Henning; Jensen, Torstein; Gjesdal, Knut

2005-01-01

Background To determine whether the use of an electronic, sensor based stethoscope affects the cardiac auscultation skills of undergraduate medical students. Methods Forty eight third year medical students were randomized to use either an electronic stethoscope, or a conventional acoustic stethoscope during clinical auscultation training. After a training period of four months, cardiac auscultation skills were evaluated using four patients with different cardiac murmurs. Two experienced cardiologists determined correct answers. The students completed a questionnaire for each patient. The thirteen questions were weighted according to their relative importance, and a correct answer was credited from one to six points. Results No difference in mean score was found between the two groups (p = 0.65). Grading and characterisation of murmurs and, if present, report of non existing murmurs were also rated. None of these yielded any significant differences between the groups. Conclusion Whether an electronic or a conventional stethoscope was used during training and testing did not affect the students' performance on a cardiac auscultation test. PMID:15882458

A New Stethoscope Design with Unique Characteristics and Development in Medical Device.

PubMed

Ghahramanifar, M; Haghani, M; Ghadimi Moghadam, A; Ghadimi Moghadam, A K

2018-03-01

As regards the significant role of stethoscopes in the diagnosis of congenital and adventitious heart diseases and prevention of irreparable complications of these diseases, the quality of hearing sound of these stethoscopes by a physician has a significant impact on the disease diagnosis. This device plays an important role in the early diagnosis of congenital heart and respiratory diseases and provides this feasibility since birth. Also, the importance of this device performance in the diagnosis of heart, cardiovascular and respiratory diseases at different age periods is not a secret. This new invented device, in comparison to a variety of available stethoscopes in the field of diagnosis, is capable of hearing the sound of a very high quality and cancelling the noise of sound that sometimes leads to wrong diagnosis or misdiagnosis. This new invented stethoscope is approved by cardiologists, lung and Infectious disease specialists as well as being registered under No. 78382 in Patent Islamic Republic of Iran.

A New Stethoscope Design with Unique Characteristics and Development in Medical Device

PubMed Central

Ghahramanifar, M.; Haghani, M.; Ghadimi Moghadam, A.; Ghadimi Moghadam, A.K.

2018-01-01

As regards the significant role of stethoscopes in the diagnosis of congenital and adventitious heart diseases and prevention of irreparable complications of these diseases, the quality of hearing sound of these stethoscopes by a physician has a significant impact on the disease diagnosis. This device plays an important role in the early diagnosis of congenital heart and respiratory diseases and provides this feasibility since birth. Also, the importance of this device performance in the diagnosis of heart, cardiovascular and respiratory diseases at different age periods is not a secret. This new invented device, in comparison to a variety of available stethoscopes in the field of diagnosis, is capable of hearing the sound of a very high quality and cancelling the noise of sound that sometimes leads to wrong diagnosis or misdiagnosis. This new invented stethoscope is approved by cardiologists, lung and Infectious disease specialists as well as being registered under No. 78382 in Patent Islamic Republic of Iran. PMID:29732350

Development and Assessment of a Dual-Mode, Noise-Immune Stethoscope for Combat Environments

DTIC Science & Technology

2010-04-01

unusable. A need exists for a stethoscope that can detect heart and lung auscultation in the presence of fixed- and rotary-wing aircraft, as well as...in ambulances and other operational environments where the ambient noise level precludes auscultation with a standard stethoscope. Possessing this...allows auscultation in high-noise environments. Because even modern military vehicles do not produce acoustic energy at the ultrasound carrier

Can education influence stethoscope hygiene?

PubMed

Holleck, Jürgen L; Merchant, Naseema; Lin, Shin; Gupta, Shaili

2017-07-01

The importance of stethoscope hygiene has been demonstrated in prior studies, and is acknowledged by guidelines, yet it is rarely done. We implemented a pilot project consisting of provider education, reminder flyers and provision of cleaning supplies at the start of clinical rotations for housestaff, medical students, and attending physicians. Hand hygiene rates did not change significantly with rates between 58% and 63% while stethoscope hygiene remained at zero. Published by Elsevier Inc.

Can we measure the ankle-brachial index using only a stethoscope? A pilot study.

PubMed

Carmo, G A L; Mandil, A; Nascimento, B R; Arantes, B D; Bittencourt, J C; Falqueto, E B; Ribeiro, A L

2009-02-01

Ankle-brachial index (ABI) is an excellent method for the diagnosis of peripheral arterial disease (PAD) when it is performed with Doppler. However, this device is not always available for primary care physicians. The ABI measured with stethoscope is an easy alternative approach, but have not been proved to be useful. To assess the accuracy of the ABI measured using a stethoscope comparatively to that of the current eligible method for the diagnosis of PAD, the Doppler ABI, and describe the characteristics of this new approach. We conducted a diagnostic study of ABI measured with a stethoscope and a Doppler probe and compared the results. Eighty-eight patients were accessed by both methods. Mean stethoscope ABI, 1.01 +/- 0.15, and mean Doppler ABI, 1.03 +/- 0.20, (P = 0.047) displayed a good correlation. Measurements of stethoscope ABI diagnostic accuracy in recognizing a Doppler ABI are described. The comparison of this data with the current gold standard method results gave a sensitivity of 71.4% [95% confidence interval (CI), 41.9-91.6] and specificity of 91.0% (95% CI, 81.5-96.6), with predictive positive value of 62.5% (95% CI, 38.6-81.5) and negative predictive value of 93.8% (95% CI, 85.2-97.6). The study accuracy was 87.7%. The area under the ROC curve was 0.895 (95% CI, 0.804-0.986, P < 0.0001). According to our study, the stethoscope ABI is a useful method to detect PAD and it may be suitable for its screening in the primary care setting.

Validity and reliability of acoustic analysis of respiratory sounds in infants

PubMed Central

Elphick, H; Lancaster, G; Solis, A; Majumdar, A; Gupta, R; Smyth, R

2004-01-01

Objective: To investigate the validity and reliability of computerised acoustic analysis in the detection of abnormal respiratory noises in infants. Methods: Blinded, prospective comparison of acoustic analysis with stethoscope examination. Validity and reliability of acoustic analysis were assessed by calculating the degree of observer agreement using the κ statistic with 95% confidence intervals (CI). Results: 102 infants under 18 months were recruited. Convergent validity for agreement between stethoscope examination and acoustic analysis was poor for wheeze (κ = 0.07 (95% CI, –0.13 to 0.26)) and rattles (κ = 0.11 (–0.05 to 0.27)) and fair for crackles (κ = 0.36 (0.18 to 0.54)). Both the stethoscope and acoustic analysis distinguished well between sounds (discriminant validity). Agreement between observers for the presence of wheeze was poor for both stethoscope examination and acoustic analysis. Agreement for rattles was moderate for the stethoscope but poor for acoustic analysis. Agreement for crackles was moderate using both techniques. Within-observer reliability for all sounds using acoustic analysis was moderate to good. Conclusions: The stethoscope is unreliable for assessing respiratory sounds in infants. This has important implications for its use as a diagnostic tool for lung disorders in infants, and confirms that it cannot be used as a gold standard. Because of the unreliability of the stethoscope, the validity of acoustic analysis could not be demonstrated, although it could discriminate between sounds well and showed good within-observer reliability. For acoustic analysis, targeted training and the development of computerised pattern recognition systems may improve reliability so that it can be used in clinical practice. PMID:15499065

A visual stethoscope to detect the position of the tracheal tube.

PubMed

Kato, Hiromi; Suzuki, Akira; Nakajima, Yoshiki; Makino, Hiroshi; Sanjo, Yoshimitsu; Nakai, Takayoshi; Shiraishi, Yoshito; Katoh, Takasumi; Sato, Shigehito

2009-12-01

Advancing a tracheal tube into the bronchus produces unilateral breath sounds. We created a Visual Stethoscope that allows real-time fast Fourier transformation of the sound signal and 3-dimensional (frequency-amplitude-time) color rendering of the results on a personal computer with simultaneous processing of 2 individual sound signals. The aim of this study was to evaluate whether the Visual Stethoscope can detect bronchial intubation in comparison with auscultation. After induction of general anesthesia, the trachea was intubated with a tracheal tube. The distance from the incisors to the carina was measured using a fiberoptic bronchoscope. While the anesthesiologist advanced the tracheal tube from the trachea to the bronchus, another anesthesiologist auscultated breath sounds to detect changes of the breath sounds and/or disappearance of bilateral breath sounds for every 1 cm that the tracheal tube was advanced. Two precordial stethoscopes placed at the left and right sides of the chest were used to record breath sounds simultaneously. Subsequently, at a later date, we randomly entered the recorded breath sounds into the Visual Stethoscope. The same anesthesiologist observed the visualized breath sounds on the personal computer screen processed by the Visual Stethoscope to examine changes of breath sounds and/or disappearance of bilateral breath sound. We compared the decision made based on auscultation with that made based on the results of the visualized breath sounds using the Visual Stethoscope. Thirty patients were enrolled in the study. When irregular breath sounds were auscultated, the tip of the tracheal tube was located at 0.6 +/- 1.2 cm on the bronchial side of the carina. Using the Visual Stethoscope, when there were any changes of the shape of the visualized breath sound, the tube was located at 0.4 +/- 0.8 cm on the tracheal side of the carina (P < 0.01). When unilateral breath sounds were auscultated, the tube was located at 2.6 +/- 1.2 cm on the bronchial side of the carina. The tube was also located at 2.3 +/- 1.0 cm on the bronchial side of the carina when a unilateral shape of visualized breath sounds was obtained using the Visual Stethoscope (not significant). During advancement of the tracheal tube, alterations of the shape of the visualized breath sounds using the Visual Stethoscope appeared before the changes of the breath sounds were detected by auscultation. Bilateral breath sounds disappeared when the tip of the tracheal tube was advanced beyond the carina in both groups.

Research Advances In Medical Care For Polytrauma Injuries And Blast Injuries

DTIC Science & Technology

2011-01-25

by air or ground ambulance. • A stethoscope that can be used to listen to heart and breath sounds in the challenging environment • The ability for...ability of medical personnel in both military and civilian settings. Description The noise immune stethoscope can be used in high-noise environments...The new stethoscope uses a traditional acoustic listening mode with the addition of ultrasound-based technology that is “noise immune.” Current

Digital stethoscopes compared to standard auscultation for detecting abnormal paediatric breath sounds.

PubMed

Kevat, Ajay C; Kalirajah, Anaath; Roseby, Robert

2017-07-01

Our study aimed to objectively describe the audiological characteristics of wheeze and crackles in children by using digital stethoscope (DS) auscultation, as well as assess concordance between standard auscultation and two different DS devices in their ability to detect pathological breath sounds. Twenty children were auscultated by a paediatric consultant doctor and digitally recorded using the Littman™ 3200 Digital Electronic Stethoscope and a Clinicloud™ DS with smart device. Using spectrographic analysis, we found those with clinically described wheeze had prominent periodic waveform segments spanning expiration for a period of 0.03-1.2 s at frequencies of 100-1050 Hz, and occasionally spanning shorter inspiratory segments; paediatric crackles were brief discontinuous sounds with a distinguishing waveform. There was moderate concordance with respect to wheeze detection between digital and standard binaural stethoscopes, and 100% concordance for crackle detection. Importantly, DS devices were more sensitive than clinician auscultation in detecting wheeze in our study. Objective definition of audio characteristics of abnormal paediatric breath sounds was achieved using DS technology. We demonstrated superiority of our DS method compared to traditional auscultation for detection of wheeze. What is Known: • The audiological characteristics of abnormal breath sounds have been well-described in adult populations but not in children. • Inter-observer agreement for detection of pathological breath sounds using standard auscultation has been shown to be poor, but the clinical value of now easily available digital stethoscopes has not been sufficiently examined. What is New: • Digital stethoscopes can objectively define the nature of pathological breath sounds such as wheeze and crackles in children. • Paediatric wheeze was better detected by digital stethoscopes than by standard auscultation performed by an expert paediatric clinician.

The two types of stethoscope systems for respiration system diagnostics of the human body

NASA Astrophysics Data System (ADS)

Abashkin, Vladimir; Achimova, Elena

2003-12-01

An acoustic multimode fiber optic sensors for medical diagnostics based upon the shutter principle has been elaborated with semiconductor laser diode as light source. The construction and the method of component preparation are described. Other type of stethoscope is electrical one. Both stethoscopes are four channels. The kinetics and dynamic vibrations and sounds of the human body can be detected, acquired and then processing by personal computer for medical diagnostics.

Auscultation

MedlinePlus

... is usually done using a tool called a stethoscope. Health care providers routinely listen to a person's ... unborn infants. This can be done with a stethoscope or with sound waves (called Doppler ultrasound). Auscultation ...

Breath sounds

MedlinePlus

The lung sounds are best heard with a stethoscope. This is called auscultation. Normal lung sounds occur ... the bottom of the rib cage. Using a stethoscope, the doctor may hear normal breathing sounds, decreased ...

[Stethoscope or staphyloscope?: Potential vector in nosocomial infections].

PubMed

Zúniga, Andrés; Mañalich, Jaime; Cortés, Rosario

2016-02-01

Healthcare-associated infections (HCAI) are a problem worldwide. In our country, the estimated incidence of HCAI is 70,000 per year. This results in an increase in the average length of hospital stay by 10 days per patient, an estimated annual cost of US $ 70 million and an overstay of 700 thousand bed days a year. For over 30 years stethoscopes have been considered as potential HCAI vectors, since pathogens like methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus strains adhere and colonize them. These organisms can be transmitted between patients if the instruments are not sanitized. Several studies conclude that disinfecting the stethoscope with isopropyl alcohol eliminates up to 99% of bacteria. Simple, economic measures such as implementation of guidelines for stethoscope disinfection are a clear opportunity for preventing infections.

New Stethoscope With Extensible Diaphragm.

PubMed

Takashina, Tsunekazu; Shimizu, Masashi; Muratake, Torakazu; Mayuzumi, Syuichi

2016-08-25

This study compared the diagnostic efficacy of the common suspended diaphragm stethoscope (SDS) with a new extensible diaphragm stethoscope (EDS) for low-frequency heart sounds. The EDS was developed by using an ethylene propylene diene monomer diaphragm. The results showed that the EDS enhanced both the volume and quality of low-frequency heart sounds, and improved the ability of examiners to auscultate such heart sounds. Based on the results of the sound analysis, the EDS is more efficient than the SDS. (Circ J 2016; 80: 2047-2049).

Explanatory model for sound amplification in a stethoscope

NASA Astrophysics Data System (ADS)

Eshach, H.; Volfson, A.

2015-01-01

In the present paper we suggest an original physical explanatory model that explains the mechanism of the sound amplification process in a stethoscope. We discuss the amplification of a single pulse, a continuous wave of certain frequency, and finally we address the resonant frequencies. It is our belief that this model may provide students with opportunities to not only better understand the amplification mechanism of a stethoscope, but also to strengthen their understanding of sound, pressure, waves, resonance modes, etc.

Reception of the stethoscope and Laënnec's book.

PubMed Central

Bishop, P J

1981-01-01

A study of contemporary book reviews and other notices enables us to trace the reception of the stethoscope and Laënnec's book between 1816 and 1826. It is quite clear from these that the stethoscope was welcomed with enthusiasm by most people who saw it as the first major diagnostic tool medicine had ever had. Laënnec's book was recognised as being the most important, interesting, accurate, and complete work on diseases of the chest that had ever been published. PMID:7031968

Celebrating Two Centuries since the Invention of the Stethoscope. René Théophile Hyacinthe Laënnec (1781-1826).

PubMed

Tomos, Ioannis; Karakatsani, Anna; Manali, Effrosyni D; Papiris, Spyros A

2016-10-01

René Théophile Hyacinthe Laënnec (1781-1826), a French physician, is considered one of the pioneers of respiratory medicine. His contribution to the invention of the stethoscope and to the development of clinical auscultation played a key role in the progress of the diagnosis of chest diseases. Almost two centuries after his invention of the stethoscope, his achievements continue to be widely appreciated and used by modern physicians in current pulmonology.

Heart Murmurs (For Kids)

MedlinePlus

... and bone between the murmur and the doctor's stethoscope. Many normal murmurs become harder to hear as ... also will listen to your heart with a stethoscope, check your pulse, and listen to your lungs. ...

Latex allergies - for hospital patients

MedlinePlus

... bands used to stop or slow blood flow) Stethoscopes (used to listen to your heart beat and ... the hospital include asking for: Equipment, such as stethoscopes and blood pressure cuffs, to be covered, so ...

Heart sounds analysis via esophageal stethoscope system in beagles.

PubMed

Park, Sang Hi; Shin, Young Duck; Bae, Jin Ho; Kwon, Eun Jung; Lee, Tae-Soo; Shin, Ji-Yun; Kim, Yeong-Cheol; Min, Gyeong-Deuk; Kim, Myoung hwan

2013-10-01

Esophageal stethoscope is less invasive and easy to handling. And it gives a lot of information. The purpose of this study is to investigate the correlation of blood pressure and heart sound as measured by esophageal stethoscope. Four male beagles weighing 10 to 12 kg were selected as experimental subjects. After general anesthesia, the esophageal stethoscope was inserted. After connecting the microphone, the heart sounds were visualized and recorded through a self-developed equipment and program. The amplitudes of S1 and S2 were monitored real-time to examine changes as the blood pressure increased and decreased. The relationship between the ratios of S1 to S2 (S1/S2) and changes in blood pressure due to ephedrine was evaluated. The same experiment was performed with different concentration of isoflurane. From S1 and S2 in the inotropics experiment, a high correlation appeared with change in blood pressure in S1. The relationship between S1/S2 and change in blood pressure showed a positive correlation in each experimental subject. In the volatile anesthetics experiment, the heart sounds decreased as MAC increased. Heart sounds were analyzed successfully with the esophageal stethoscope through the self-developed program and equipment. A proportional change in heart sounds was confirmed when blood pressure was changed using inotropics or volatile anesthetics. The esophageal stethoscope can achieve the closest proximity to the heart to hear sounds in a non-invasive manner.

Novel approach to the diagnosis of fractures in an austere environment using a stethoscope and a cellular phone.

PubMed

Matzek, Brett A; Fivecoat, Phillip T; Ritz, Reis B

2014-03-01

Fracture diagnosis in the austere environment where radiographic tests are not available can be a challenge. In the past, a diagnostic technique has been described using a tuning fork and stethoscope to assess decreased sound conduction in the fractured extremity. In this study, we evaluate the use of a cellular phone's vibrate function and a stethoscope to limit equipment carried by expeditionary practitioners. The purpose of this study was to evaluate the accuracy of fracture diagnosis using a cellular phone and stethoscope. This is a pilot study to assess the usefulness of the above technique before clinical implementation. In 3 cadavers, we created fractures of the humerus and femur. Twenty-seven emergency medicine residents and an attending physician performed the diagnostic technique. Overall, the use of the cellular phone and stethoscope resulted in a sensitivity of 73% (95% confidence interval [CI]: 0.64 to 0.81) and a specificity of 83% (95% CI: 0.77 to 0.88), with a positive predicted value of 68% (95% CI: 0.59 to 0.77) and a negative predicted value of 86% (95% CI: 0.81 to 0.90). Positive likelihood ratio was 4.3, and negative likelihood ratio was 0.32. The use of a cellular phone and stethoscope may be a useful tool for the diagnosis of fractures in the austere environment. However, further study is needed to validate these findings in the clinical environment. Published by Wilderness Medical Society on behalf of Wilderness Medical Society.

An alternative noninvasive technique for the treatment of iatrogenic femoral pseudoaneurysms: stethoscope-guided compression.

PubMed

Korkmaz, Ahmet; Duyuler, Serkan; Kalayci, Süleyman; Türker, Pinar; Sahan, Ekrem; Maden, Orhan; Selçuk, Mehmet Timur

2013-06-01

latrogenic femoral pseudoaneurysm is a well-known vascular access site complication. Many invasive and noninvasive techniques have been proposed for the management of this relatively common complication. In this study, we aimed to evaluate efficiency and safety of stethoscope-guided compression as a novel noninvasive technique in the femoral pseudoaneurysm treatment. We prospectively included 29 consecutive patients with the diagnosis of femoral pseudoaneurysm who underwent coronary angiography. Patients with a clinical suspicion of femoral pseudoaneurysm were referred to colour Doppler ultrasound evaluation. The adult (large) side of the stethoscope was used to determine the location where the bruit was best heard. Then compression with the paediatric (small) side of the stethoscope was applied until the bruit could no longer be heard and compression was maintained for at least two sessions. Once the bruit disappeared, a 12-hour bed rest with external elastic compression was advised to the patients, in order to prevent disintegration of newly formed thrombosis. Mean pseudoaneurysm size was 1.7 +/- 0.4 cmx 3.0 +/- 0.9 cm and the mean duration of compression was 36.2 +/- 8.5 minutes.Twenty-six (89.6%) of these 29 patients were successfully treated with stethoscope-guided compression. In 18 patients (62%), the pseuodoaneurysms were successfully closed after 2 sessions of 15-minute compression. No severe complication was observed. Stethoscope-guided compression of femoral pseudoaneurysms is a safe and effective novel technique which requires less equipment and expertise than other contemporary methods.

Comparison of stethoscope bell and diaphragm, and of stethoscope tube length, for clinical blood pressure measurement.

PubMed

Liu, Chengyu; Griffiths, Clive; Murray, Alan; Zheng, Dingchang

2016-06-01

This study investigated the effect of stethoscope side and tube length on auscultatory blood pressure (BP) measurement. Thirty-two healthy participants were studied. For each participant, four measurements with different combinations of stethoscope characteristics (bell or diaphragm side, standard or short tube length) were each recorded at two repeat sessions, and eight Korotkoff sound recordings were played twice on separate days to one experienced listener to determine the systolic and diastolic BPs (SBP and DBP). Analysis of variance was carried out to study the measurement repeatability between the two repeat sessions and between the two BP determinations on separate days, as well as the effects of stethoscope side and tube length. There was no significant paired difference between the repeat sessions and between the repeat determinations for both SBP and DBP (all P-values>0.10, except the repeat session for SBP using short tube and diaphragm). The key result was that there was a small but significantly higher DBP on using the bell in comparison with the diaphragm (0.66 mmHg, P=0.007), and a significantly higher SBP on using the short tube in comparison with the standard length (0.77 mmHg, P=0.008). This study shows that stethoscope characteristics have only a small, although statistically significant, influence on clinical BP measurement. Although this helps understand the measurement technique and resolves questions in the published literature, the influence is not clinically significant.

Comparison of stethoscope bell and diaphragm, and of stethoscope tube length, for clinical blood pressure measurement

PubMed Central

Griffiths, Clive; Murray, Alan; Zheng, Dingchang

2016-01-01

Objective This study investigated the effect of stethoscope side and tube length on auscultatory blood pressure (BP) measurement. Methods Thirty-two healthy participants were studied. For each participant, four measurements with different combinations of stethoscope characteristics (bell or diaphragm side, standard or short tube length) were each recorded at two repeat sessions, and eight Korotkoff sound recordings were played twice on separate days to one experienced listener to determine the systolic and diastolic BPs (SBP and DBP). Analysis of variance was carried out to study the measurement repeatability between the two repeat sessions and between the two BP determinations on separate days, as well as the effects of stethoscope side and tube length. Results There was no significant paired difference between the repeat sessions and between the repeat determinations for both SBP and DBP (all P-values>0.10, except the repeat session for SBP using short tube and diaphragm). The key result was that there was a small but significantly higher DBP on using the bell in comparison with the diaphragm (0.66 mmHg, P=0.007), and a significantly higher SBP on using the short tube in comparison with the standard length (0.77 mmHg, P=0.008). Conclusion This study shows that stethoscope characteristics have only a small, although statistically significant, influence on clinical BP measurement. Although this helps understand the measurement technique and resolves questions in the published literature, the influence is not clinically significant. PMID:26741415

In defense of the stethoscope.

PubMed

Murphy, Raymond Lh

2008-03-01

The stethoscope is widely considered to be an unreliable instrument. Many studies document the significant observer variability in its use. Numerous other diagnostic tools are available that are generally regarded to provide more reliable diagnostic information. Some even argue that teaching of the ancient art should be de-emphasized in medical schools. Yet auscultation with an acoustic stethoscope can provide important, even life-saving, information. The purpose of this article is to present evidence that supports the use of the stethoscope in clinical medicine. The argument for the stethoscope will be made by presenting relevant investigations, including clinical studies acknowledged to meet the criteria of evidence-based medicine. It will focus on studies that have employed computerized acoustic technology to correlate lung sounds with disease states. This technology has advanced in recent years, which has stimulated a resurgence of interest in auscultation. Numerous studies have been done that utilized objective methods that circumvented the problem of observer variability. There is now a good deal of scientific evidence to support the hypothesis that lung sounds contain information that is clinically useful. This technology also allows this information to be collected more efficiently than previously possible. Advances in educational technology have made it possible to impart information on auscultation much more easily than was possible in the past. Contrary to predictions, the stethoscope is not likely to be relegated to the museum shelf in the near future. Computer technology is making it an even more useful clinical instrument.

The efficacy of stethoscope placement when not in use: traditional versus “cool”

PubMed Central

Hanley, William B.; Hanley, Anthony J.G.

2000-01-01

Objective To determine whether the “cool” or circumcervical placement of the stethoscope when not in use is as efficacious as the traditional placement in terms of transfer time to the functional position. Methods Measurement of time taken by 100 health care professionals in each group to transfer stethoscope to functional position. Results and interpretation The cool group was much slower than the traditional group, despite their younger years. This wasted time could translate into a substantial financial burden on Canada's health care system. PMID:11138413

Contamination of stethoscopes and physicians' hands after a physical examination.

PubMed

Longtin, Yves; Schneider, Alexis; Tschopp, Clément; Renzi, Gesuèle; Gayet-Ageron, Angèle; Schrenzel, Jacques; Pittet, Didier

2014-03-01

To compare the contamination level of physicians' hands and stethoscopes and to explore the risk of cross-transmission of microorganisms through the use of stethoscopes. We conducted a structured prospective study between January 1, 2009, and May 31, 2009, involving 83 inpatients at a Swiss university teaching hospital. After a standardized physical examination, 4 regions of the physician's gloved or ungloved dominant hand and 2 sections of the stethoscopes were pressed onto selective and nonselective media; 489 surfaces were sampled. Total aerobic colony counts (ACCs) and total methicillin-resistant Staphylococcus aureus (MRSA) colony-forming unit (CFU) counts were assessed. Median total ACCs (interquartile range) for fingertips, thenar eminence, hypothenar eminence, hand dorsum, stethoscope diaphragm, and tube were 467, 37, 34, 8, 89, and 18, respectively. The contamination level of the diaphragm was lower than the contamination level of the fingertips (P<.001) but higher than the contamination level of the thenar eminence (P=.004). The MRSA contamination level of the diaphragm was higher than the MRSA contamination level of the thenar eminence (7 CFUs/25 cm(2) vs 4 CFUs/25 cm(2); P=.004). The correlation analysis for both total ACCs and MRSA CFU counts revealed that the contamination level of the diaphragm was associated with the contamination level of the fingertips (Spearman's rank correlation coefficient, ρ=0.80; P<.001 and ρ=0.76; P<.001, respectively). Similarly, the contamination level of the stethoscope tube increased with the increase in the contamination level of the fingertips for both total ACCs and MRSA CFU counts (ρ=0.56; P<.001 and ρ=.59; P<.001, respectively). These results suggest that the contamination level of the stethoscope is substantial after a single physical examination and comparable to the contamination of parts of the physician's dominant hand. Copyright © 2014 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Ventricular Septal Defect (VSD)

MedlinePlus

... hears a murmur while listening to your baby's heart with a stethoscope. Sometimes VSDs can be detected by ultrasound before ... murmur your doctor hears when listening to your heart with a stethoscope. When to see a doctor Call your doctor ...

Cardiovascular Sound and the Stethoscope, 1816 to 2016

PubMed Central

Segall, Harold N.

1963-01-01

Cardiovascular sound escaped attention until Laennec invented and demonstrated the usefulness of the stethoscope. Accuracy of diagnosis using cardiovascular sounds as clues increased with improvement in knowledge of the physiology of circulation. Nearly all currently acceptable clinicopathological correlations were established by physicians who used the simplest of stethoscopes or listened with the bare ear. Certain refinements followed the use of modern methods which afford greater precision in timing cardiovascular sounds. These methods contribute to educating the human ear, so that those advantages may be applied which accrue from auscultation, plus the method of writing quantitative symbols to describe what is heard, by focusing the sense of hearing on each segment of the cardiac cycle in turn. By the year 2016, electronic systems of collecting and analyzing data about the cardiovascular system may render the stethoscope obsolete. ImagesFig. 1Fig. 2Fig. 3Fig. 5Fig. 8 PMID:13987676

Reliability of Doppler and stethoscope methods of determining systolic blood pressures: considerations for calculating an ankle-brachial index.

PubMed

Chesbro, Steven B; Asongwed, Elmira T; Brown, Jamesha; John, Emmanuel B

2011-01-01

The purposes of this study were to: (1) identify the interrater and intrarater reliability of systolic blood pressures using a stethoscope and Doppler to determine an ankle-brachial index (ABI), and (2) to determine the correlation between the 2 methods. Peripheral arterial disease (PAD) affects approximately 8 to 12 million people in the United States, and nearly half of those with this disease are asymptomatic. Early detection and prompt treatment of PAD will improve health outcomes. It is important that clinicians perform tests that determine the presence of PAD. Two individual raters trained in ABI procedure measured the systolic blood pressures of 20 individuals' upper and lower extremities. Standard ABI measurement protocols were observed. Raters individually recorded the systolic blood pressures of each extremity using a stethoscope and a Doppler, for a total of 640 independent measures. Interrater reliability of Doppler measurements to determine SBP at the ankle was very strong (intraclass correlation coefficient [ICC], 0.93-0.99) compared to moderate to strong reliability using a stethoscope (ICC, 0.64-0.87). Agreement between the 2 devices to determine SBP was moderate to very weak (ICC, 0.13-0.61). Comparisons of the use of Doppler and stethoscope to determine ABI showed weak to very weak intrarater correlation (ICC, 0.17-0.35). Linear regression analysis of the 2 methods to determine ABI showed positive but weak to very weak correlations (r2 = .013, P = .184). A Doppler ultrasound is recommended over a stethoscope for accuracy in systolic pressure readings for ABI measurements.

iStethoscope: a demonstration of the use of mobile devices for auscultation.

PubMed

Bentley, Peter J

2015-01-01

iStethoscope Pro is the first piece of software (an "App") produced for iOS devices, which enabled users to exploit their smartphones, music players, or tablets as stethoscopes. The software exploits the built-in microphone (and supports externally added microphones) and performs real-time amplification and filtering to enable heart sounds to be heard with high fidelity. The software also enables the heart sounds to be recorded, analyzed using a spectrogram, and to be transmitted to others via e-mail. This chapter describes the motivation, functionality, and results from this work.

Environmental Contaminants in Hospital Settings and Progress in Disinfecting Techniques

PubMed Central

Ceriale, Emma; Lenzi, Daniele; Burgassi, Sandra; Azzolini, Elena; Manzi, Pietro

2013-01-01

Medical devices, such as stethoscopes, and other objects found in hospital, such as computer keyboards and telephone handsets, may be reservoirs of bacteria for healthcare-associated infections. In this cross-over study involving an Italian teaching hospital we evaluated microbial contamination (total bacterial count (TBC) at 36°C/22°C, Staphylococcus spp., moulds, Enterococcus spp., Pseudomonas spp., E. coli, total coliform bacteria, Acinetobacter spp., and Clostridium difficile) of these devices before and after cleaning and differences in contamination between hospital units and between stethoscopes and keyboards plus handsets. We analysed 37 telephone handsets, 27 computer keyboards, and 35 stethoscopes, comparing their contamination in four hospital units. Wilcoxon signed-rank and Mann-Whitney tests were used. Before cleaning, many samples were positive for Staphylococcus spp. and coliforms. After cleaning, CFUs decreased to zero in most comparisons. The first aid unit had the highest and intensive care the lowest contamination (P < 0.01). Keyboards and handsets had higher TBC at 22°C (P = 0.046) and mould contamination (P = 0.002) than stethoscopes. Healthcare professionals should disinfect stethoscopes and other possible sources of bacterial healthcare-associated infections. The cleaning technique used was effective in reducing bacterial contamination. Units with high patient turnover, such as first aid, should practise stricter hygiene. PMID:24286078

Use of 90% ethanol to decontaminate stethoscopes in resource limited settings.

PubMed

Raghubanshi, Bijendra Raj; Sapkota, Supriya; Adhikari, Arjab; Dutta, Aman; Bhattarai, Utsuk; Bhandari, Rastriyata

2017-01-01

In developing countries like Nepal, 90% ethanol is cheap and is available in most hospitals. The unavailability of isopropyl alcohol (IPA) in these settings led us to compare the efficacy between 90% ethanol and isopropyl alcohol pads in reducing the bacterial contamination of diaphragm of stethoscope. A randomized blinded experimental study was carried out to determine the difference between cleaning stethoscopes with 90% ethanol and IPA. Cultures of diaphragm were taken before and after cleaning with one of the cleaning agent. Colony forming units (CFU) count and organism identification was done by a blinded investigator. CFU before and after cleaning were compared using Wilcoxon signed-rank test. Mann Whitney U test was used to compare the decrease in CFU count between the cleaning agents. About 30% of the stethoscopes harbored potential pathogens. Significant reduction in CFU was observed with both IPA (Wilcoxon signed-rank test, P value <0.001) and 90% ethanol (Wilcoxon signed-rank test, P value <0.001). Comparing median decrease in CFU between cleaning with IPA and with 90% ethanol, no significant difference was found (Mann Whitney U test; U = 1357, P value >0.05). Both 90% ethanol and IPA are equally effective in decontaminating the diaphragm of stethoscope. Selection of agent should be done on the basis of cost and availability.

Correlation of blood pressure and the ratio of S1 to S2 as measured by esophageal stethoscope and wireless bluetooth transmission.

PubMed

Hoon Lim, Kyoung; Duck Shin, Young; Hi Park, Sang; Ho Bae, Jin; Jae Lee, Hong; Jung Kim, Seon; Yun Shin, Ji; Jin Choi, Young

2013-07-01

Objective : Esophageal stethoscope has the advantage of being non-invasive, easily placed and capability to monitor the heart sound. This study was designed to determine whether the ratio of S1 to S2 analyzed by esophageal stethoscope and wireless bluetooth transmission can be accurate indicator that express the correlation with blood pressure. Total 33 adult male and female without cardiac disorder and with normal heart rhythm were selected randomly as the subjects of this Study. Two microphones were used with one for acquisition of heart sound by connecting it to the esophageal stethoscope while the other was used to measure the background noise in the operating room. After having transmitted the heart sound measured with the esophageal stethoscope to the receiver by using bluetooth module, it was saved in PC and outputted, following removal of noise in the operating room and the respiratory sound. S1 and S2 were measured with computation of the ratio of S1 to S2. Correlations between the systolic blood pressure with each of the S1, S2 and ratio of S1 to S2 were examined by using correlation analysis. The ratio of S1 to S2 displayed the highest correlation with the systolic blood pressure, with S1 and S2 also displaying positive correlation with the systolic blood pressure. As the result of analysis of the heart sound and the systolic blood pressure measured by using the esophageal stethoscope, the radio of S1 to S2 displayed greater correlation with the systolic blood pressure in comparison to the S1.

Time Effectiveness of Ultraviolet C Light (UVC) Emitted by Light Emitting Diodes (LEDs) in Reducing Stethoscope Contamination.

PubMed

Messina, Gabriele; Fattorini, Mattia; Nante, Nicola; Rosadini, Daniele; Serafini, Andrea; Tani, Marco; Cevenini, Gabriele

2016-09-23

Today it is well demonstrated that stethoscopes can be as contaminated as hands, which are a recognized source of Health-Care Associated Infections (HCAIs). Ultraviolet C (UVC) light has proven disinfection capacity and the innovative UVC technology of Light Emitting Diode (LED) shows several potential benefits. To verify whether the use of UVC LEDs is effective and reliable in stethoscope membrane disinfection after prolonged use, a pre-post intervention study was conducted. A total of 1668 five-minute cycles were performed on two UVC LEDs to simulate their use; thereafter, their disinfection capacity was tested on stethoscope membranes used on a previously auscultated volunteer. Then, a further 1249 cycles were run and finally the LEDs were tested to assess performance in reducing experimental contamination by Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli on the stethoscope membrane. Baseline volunteer contamination identified 104 Colony Forming Units (CFUs) while treated Petri dishes had 12 and 15 CFUs (p < 0.001). Statistically significant differences (p < 0.001) were also found relating to the reduction of specific bacteria: in particular, after treatment no CFU were observed for S. aureus and E. coli. UVC LEDs demonstrated the capacity to maintain high levels of disinfection after more than 240 h of use and they were effective against common microorganisms that are causative agents of HCAIs.

Time Effectiveness of Ultraviolet C Light (UVC) Emitted by Light Emitting Diodes (LEDs) in Reducing Stethoscope Contamination

PubMed Central

Messina, Gabriele; Fattorini, Mattia; Nante, Nicola; Rosadini, Daniele; Serafini, Andrea; Tani, Marco; Cevenini, Gabriele

2016-01-01

Today it is well demonstrated that stethoscopes can be as contaminated as hands, which are a recognized source of Health-Care Associated Infections (HCAIs). Ultraviolet C (UVC) light has proven disinfection capacity and the innovative UVC technology of Light Emitting Diode (LED) shows several potential benefits. To verify whether the use of UVC LEDs is effective and reliable in stethoscope membrane disinfection after prolonged use, a pre-post intervention study was conducted. A total of 1668 five-minute cycles were performed on two UVC LEDs to simulate their use; thereafter, their disinfection capacity was tested on stethoscope membranes used on a previously auscultated volunteer. Then, a further 1249 cycles were run and finally the LEDs were tested to assess performance in reducing experimental contamination by Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli on the stethoscope membrane. Baseline volunteer contamination identified 104 Colony Forming Units (CFUs) while treated Petri dishes had 12 and 15 CFUs (p < 0.001). Statistically significant differences (p < 0.001) were also found relating to the reduction of specific bacteria: in particular, after treatment no CFU were observed for S. aureus and E. coli. UVC LEDs demonstrated the capacity to maintain high levels of disinfection after more than 240 h of use and they were effective against common microorganisms that are causative agents of HCAIs. PMID:27669273

Explanatory Model for Sound Amplification in a Stethoscope

ERIC Educational Resources Information Center

Eshach, H.; Volfson, A.

2015-01-01

In the present paper we suggest an original physical explanatory model that explains the mechanism of the sound amplification process in a stethoscope. We discuss the amplification of a single pulse, a continuous wave of certain frequency, and finally we address the resonant frequencies. It is our belief that this model may provide students with…

Vital Signs Rate Meter.

DTIC Science & Technology

1987-09-01

stethoscope . Auscultation in respiratory medicine, however, has advanced slowly since Laennec established auscultation of lung sounds as a means of... stethoscope and the ear have limitations in their use as instruments for the evaluation of respiratory sounds. Respiratory sounds have a wide spectrum...Amplification, Rectification and Level-shft ing Stage ... 11 Respiratory Sound Circuitry ....... .................. ... 11 Sound Sensor

Polyvinylidene fluoride (PVDF) vibration sensor for stethoscope and contact microphones

NASA Astrophysics Data System (ADS)

Toda, Minoru; Thompson, Mitchell

2005-09-01

This paper describes a new type of contact vibration sensor made by bonding piezoelectric PVDF film to a curved frame structure. The concave surface of the film is bonded to a rubber piece having a front contact face. Vibration is transmitted from this face through the rubber to the surface of the PVDF film. Pressure normal to the surface of the film is converted to circumferential strain, and an electric field is induced by the piezoelectric effect. The frequency response of the device was measured using an accelerometer mounted between the rubber face and a rigid vibration exciter plate. Sensitivity (voltage per unit displacement) was deduced from the device output and measured acceleration. The sensitivity was flat from 16 Hz to 3 kHz, peaking at 6 kHz due to a structural resonance. Calculations predicting performance against human tissue (stethoscope or contact microphone) show results similar to data measured against the metal vibrator. This implies that an accelerometer can be used for calibrating a stethoscope or contact microphone. The observed arterial pulse waveform showed more low-frequency content than a conventional electronic stethoscope.

Bronchial intubation could be detected by the visual stethoscope techniques in pediatric patients.

PubMed

Kimura, Tetsuro; Suzuki, Akira; Mimuro, Soichiro; Makino, Hiroshi; Sato, Shigehito

2012-12-01

We created a system that allows the visualization of breath sounds (visual stethoscope). We compared the visual stethoscope technique with auscultation for the detection of bronchial intubation in pediatric patients. In the auscultation group, an anesthesiologist advanced the tracheal tube, while another anesthesiologist auscultated bilateral breath sounds to detect the change and/or disappearance of unilateral breath sounds. In the visualization group, the stethoscope was used to detect changes in breath sounds and/or disappearance of unilateral breath sounds. The distance from the edge of the mouth to the carina was measured using a fiberoptic bronchoscope. Forty pediatric patients were enrolled in the study. At the point at which irregular breath sounds were auscultated, the tracheal tube was located at 0.5 ± 0.8 cm on the bronchial side from the carina. When a detectable change of shape of the visualized breath sound was observed, the tracheal tube was located 0.1 ± 1.2 cm on the bronchial side (not significant). At the point at which unilateral breath sounds were auscultated or a unilateral shape of the visualized breath sound was observed, the tracheal tube was 1.5 ± 0.8 or 1.2 ± 1.0 cm on the bronchial side, respectively (not significant). The visual stethoscope allowed to display the left and the right lung sound simultaneously and detected changes of breath sounds and unilateral breath sound as a tracheal tube was advanced. © 2012 Blackwell Publishing Ltd.

Decontamination of stethoscope membranes with chlorhexidine: Should it be recommended?

PubMed

Álvarez, José A; Ruíz, Susana R; Mosqueda, Juan L; León, Ximena; Arreguín, Virginia; Macías, Alejandro E; Macias, Juan H

2016-11-01

To determine differences in the recontamination of stethoscope membranes after cleaning with chlorhexidine, triclosan, or alcohol. Experimental, controlled, blinded trial to determine differences in the bacterial load on stethoscope membranes. Membranes were cultured by direct imprint after disinfection with 70% isopropyl alcohol, 1% triclosan, or 1% chlorhexidine and normal use for 4 hours. As a baseline and an immediate effect control, bacterial load of membranes without disinfection and after 1 minute of disinfection with isopropyl alcohol was determined as well. Three hundred seventy cultures of in-use stethoscopes were taken, 74 from each arm. In the baseline arm the median growth was 10 CFU (interquartile range [IQR], 32-42 CFU); meanwhile, in the isopropyl alcohol immediate-effect arm it was 0 CFU (IQR, 0-0 CFU). In the arms cultured after 4 hours, a median growth of 8 CFU (IQR, 1-28 CFU) in the isopropyl alcohol arm, 4 CFU (IQR, 0-17 CFU) in the triclosan arm, and 0 CFU (IQR, 0-1 CFU) in the chlorhexidine arm were seen. No significant differences were observed between the bacterial load of the chlorhexidine arm (after 4 hours of use) and that of the isopropyl alcohol arm (after 1 minute without use) (Z= 2.41; P > .05). Chlorhexidine can inhibit recontamination of stethoscope membranes and its use could help avoid cross-infection. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Feasibility of an electronic stethoscope system for monitoring neonatal bowel sounds.

PubMed

Dumas, Jasmine; Hill, Krista M; Adrezin, Ronald S; Alba, Jorge; Curry, Raquel; Campagna, Eric; Fernandes, Cecilia; Lamba, Vineet; Eisenfeld, Leonard

2013-09-01

Bowel dysfunction remains a major problem in neonates. Traditional auscultation of bowel sounds as a diagnostic aid in neonatal gastrointestinal complications is limited by skill and inability to document and reassess. Consequently, we built a unique prototype to investigate the feasibility of an electronic monitoring system for continuous assessment of bowel sounds. We attained approval by the Institutional Review Boards for the investigational study to test our system. The system incorporated a prototype stethoscope head with a built-in microphone connected to a digital recorder. Recordings made over extended periods were evaluated for quality. We also considered the acoustic environment of the hospital, where the stethoscope was used. The stethoscope head was attached to the abdomen with a hydrogel patch designed especially for this purpose. We used the system to obtain recordings from eight healthy, full-term babies. A scoring system was used to determine loudness, clarity, and ease of recognition comparing it to the traditional stethoscope. The recording duration was initially two hours and was increased to a maximum of eight hours. Median duration of attachment was three hours (3.75, 2.68). Based on the scoring, the bowel sound recording was perceived to be as loud and clear in sound reproduction as a traditional stethoscope. We determined that room noise and other noises were significant forms of interference in the recordings, which at times prevented analysis. However, no sound quality drift was noted in the recordings and no patient discomfort was noted. Minimal erythema was observed over the fixation site which subsided within one hour. We demonstrated the long-term recording of infant bowel sounds. Our contributions included a prototype stethoscope head, which was affixed using a specially designed hydrogel adhesive patch. Such a recording can be reviewed and reassessed, which is new technology and an improvement over current practice. The use of this system should also, theoretically, reduce risk of infection. Based on our research we concluded that while automatic assessment of bowel sounds is feasible over an extended period, there will be times when analysis is not possible. One limitation is noise interference. Our larger goals include producing a meaningful vital sign to characterize bowel sounds that can be produced in real-time, as well as providing automatic control for patient feeding pumps.

Anesthesia Provider’s Use of the Precordial or Esophageal Stethoscope: Is Anyone Still Listening to the Patient

DTIC Science & Technology

1996-06-01

USAF, NC and Dr. Maura McAuliffe, Lt. Col. , USAF, NC. Dr. Hall served as my qualitative data advisor. Her assi stance ensured an accurate...esophageal stethoscope, Anesthesiology, 65 (5), 534-536. Prielipp, R. c., Kelly , J. S., & Roy, R. C. (1995, August). Use of esophageal or

Electronic stethoscope with frequency shaping and infrasonic recording capabilities.

PubMed

Gordon, E S; Lagerwerff, J M

1976-03-01

A small electronic stethoscope with variable frequency response characteristics has been developed for aerospace and research applications. The system includes a specially designed piezoelectric pickup and amplifier with an overall frequency response from 0.7 to 5,000 HZ (-3 dB points) and selective bass and treble boost or cut of up to 15 dB. A steep slope, high pass filter can be switched in for ordinary clinical auscultation without overload distortion from strong infrasonic signal inputs. A commercial stethoscope-type headset, selected for best overall response, is used which can adequately handle up to 100 mW of audio power delivered from the amplifier. The active components of the amplifier consist of only four opamp-type integrated circuits.

The correlation between the first heart sound and cardiac output as measured by using digital esophageal stethoscope under anaesthesia.

PubMed

Duck Shin, Young; Hoon Yim, Kyoung; Hi Park, Sang; Wook Jeon, Yong; Ho Bae, Jin; Soo Lee, Tae; Hwan Kim, Myoung; Jin Choi, Young

2014-03-01

The use of an esophageal stethoscope is a basic heart sounds monitoring procedure performed in patients under general anesthesia. As the size of the first heart sound can express the left ventricle function, its correlation with cardiac output should be investigated. The aim of this study was to investigate the effects of cardiac output (CO) on the first heart sound (S1) amplitude. Methods : Six male beagles were chosen. The S1 was obtained with the newly developed esophageal stethoscope system. CO was measured using NICOM, a non-invasive CO measuring device. Ephedrine and beta blockers were administered to the subjects to compare changes in figures, and the change from using an inhalation anesthetic was also compared. The S1 amplitude displayed positive correlation with the change rate of CO (r = 0.935, p < 0.001). The heart rate measured using the esophageal stethoscope and ECG showed considerably close figures through the Bland-Altman plot and showed a high positive correlation (r = 0.988, p < 0,001). In beagles, the amplitude of S1 had a significant correlation with changes in CO in a variety of situations.

Difference in thermodynamics between two types of esophageal temperature probes: Insights from an experimental study.

PubMed

Gianni, Carola; Atoui, Moustapha; Mohanty, Sanghamitra; Trivedi, Chintan; Bai, Rong; Al-Ahmad, Amin; Burkhardt, J David; Gallinghouse, G Joseph; Hranitzky, Patrick M; Horton, Rodney P; Sanchez, Javier E; Di Biase, Luigi; Lakkireddy, Dhanunjaya R; Natale, Andrea

2016-11-01

Luminal esophageal temperature monitoring is performed with a variety of temperature probes, but little is known about the relationship between the structure of a given probe and its thermodynamic characteristics. The purpose of this study was to evaluate the difference in thermodynamics between a 9Fr standard esophageal probe and an 18Fr esophageal stethoscope. In the experimental setting, each probe was submerged in a constant temperature water bath maintained at 42°C; in the patient setting, we monitored the temperature with both probes at the same time. The time constant of the stethoscope was higher than that of the probe (33.5 vs 8.3 s). Compared to the probe, the mean temperature measured by the stethoscope at 10 seconds was significantly lower (22.5°C ± 0.4°C vs 33.5°C ± 0.3°C, P<.0001), whereas the time to reach the peak temperature was significantly longer (132.6 ± 5.9 s vs 38.8 ± 1.0 s, P<.0001). Even in the ablation cases we observed that when the esophageal probe reached a peak temperature of 39.6°C ± 0.3°C, the esophageal stethoscope still displayed a temperature of 37.3°C ± 0.2°C (a mean of 2.39°C ± 0.3°C lower, P<.0001), showing a <0.5°C increase in temperature half of the times. The 18Fr esophageal stethoscope has a significantly slower time response compared to the 9Fr esophageal probe. In the clinical setting, this might result in a considerable underestimation of the luminal esophageal temperature with potentially fatal consequences. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Reference values for respiratory rate in the first 3 years of life.

PubMed

Rusconi, F; Castagneto, M; Gagliardi, L; Leo, G; Pellegatta, A; Porta, N; Razon, S; Braga, M

1994-09-01

Raised respiratory rate is a useful sign to diagnose lower respiratory infections in childhood. However, the normal range for respiratory rate has not been defined in a proper, large sample. To assess the respiratory rate in a large number of infants and young children in order to construct percentile curves by age; to determine the repeatability to the assessment using a stethoscope and compare it with observation. Respiratory rate was recorded for 1 minute with a stethoscope in 618 infants and children, aged 15 days to 3 years old, without respiratory infections or any other severe disease when awake and calm and when asleep. In 50 subjects we compared respiratory rate taken 30 to 60 minutes apart to assess repeatability, and in 50 others we compared simultaneous counts obtained by stethoscope versus observation. Repeatability was good as the standard deviation of differences was 2.5 breaths/minute in awake and 1.7 breaths/minute in asleep children. Respiratory rate obtained with a stethoscope was systematically higher than that obtained by observation (mean difference 2.6 breaths/minute in awake and 1.8 breaths/minute in asleep children; P = .015 and P < .001, respectively). A decrease in respiratory rate with age was seen for both states, and it was faster in the first few months of life when also a greater dispersion of values was observed. A second degree polynomial curve accurately fitted the data. Reference percentile values were developed from these data. The repeatability of respiratory rate measured with a stethoscope was good. Percentile curves would be particularly helpful in the first months of life when the decline in respiratory rate is very rapid and prevents to use cut off values for defining "normality."

Preliminary Characterization of the Noise-Immune Stethoscope (NIS) in High Ambient Noise Environment Using a Reverberation Sound Chamber

DTIC Science & Technology

2010-02-01

unlimited This report details the preliminary testing of advanced technology development for clinical auscultation in high noise environments. The Noise...represents a viable answer to the need for clinical auscultation in high noise environments across the spectrum of casualty care. stethoscope, auscultation ...sounds, and these sounds prove very useful for clinical assessment and diagnosis (Bloch, 1993). Since that time, clinical auscultation by way of a

Portable bedside ultrasound: the visual stethoscope of the 21st century

PubMed Central

2012-01-01

Over the past decade technological advances in the realm of ultrasound have allowed what was once a cumbersome and large machine to become essentially hand-held. This coupled with a greater understanding of lung sonography has revolutionized our bedside assessment of patients. Using ultrasound not as a diagnostic test, but instead as a component of the physical exam, may allow it to become the stethoscope of the 21st century. PMID:22400903

Performance evaluation of heart sound cancellation in FPGA hardware implementation for electronic stethoscope.

PubMed

Chao, Chun-Tang; Maneetien, Nopadon; Wang, Chi-Jo; Chiou, Juing-Shian

2014-01-01

This paper presents the design and evaluation of the hardware circuit for electronic stethoscopes with heart sound cancellation capabilities using field programmable gate arrays (FPGAs). The adaptive line enhancer (ALE) was adopted as the filtering methodology to reduce heart sound attributes from the breath sounds obtained via the electronic stethoscope pickup. FPGAs were utilized to implement the ALE functions in hardware to achieve near real-time breath sound processing. We believe that such an implementation is unprecedented and crucial toward a truly useful, standalone medical device in outpatient clinic settings. The implementation evaluation with one Altera cyclone II-EP2C70F89 shows that the proposed ALE used 45% resources of the chip. Experiments with the proposed prototype were made using DE2-70 emulation board with recorded body signals obtained from online medical archives. Clear suppressions were observed in our experiments from both the frequency domain and time domain perspectives.

Remote optical stethoscope and optomyography sensing device

NASA Astrophysics Data System (ADS)

Golberg, Mark; Polani, Sagi; Ozana, Nisan; Beiderman, Yevgeny; Garcia, Javier; Ruiz-Rivas Onses, Joaquin; Sanz Sabater, Martin; Shatsky, Max; Zalevsky, Zeev

2017-02-01

In this paper we present the usage of photonic remote laser based device for sensing nano-vibrations for detection of muscle contraction and fatigue, eye movements and in-vivo estimation of glucose concentration. The same concept is also used to realize a remote optical stethoscope. The advantage of doing the measurements from a distance is in preventing passage of infections as in the case of optical stethoscope or in the capability to monitor e.g. sleep quality without disturbing the patient. The remote monitoring of glucose concentration in the blood stream and the capability to perform opto-myography for the Messer muscles (chewing) is very useful for nutrition and weight control. The optical configuration for sensing the nano-vibrations is based upon analyzing the statistics of the secondary speckle patterns reflected from various tissues along the body of the subjects. Experimental results present the preliminary capability of the proposed configuration for the above mentioned applications.

Variation of the Korotkoff Stethoscope Sounds During Blood Pressure Measurement: Analysis Using a Convolutional Neural Network.

PubMed

Pan, Fan; He, Peiyu; Liu, Chengyu; Li, Taiyong; Murray, Alan; Zheng, Dingchang

2017-11-01

Korotkoff sounds are known to change their characteristics during blood pressure (BP) measurement, resulting in some uncertainties for systolic and diastolic pressure (SBP and DBP) determinations. The aim of this study was to assess the variation of Korotkoff sounds during BP measurement by examining all stethoscope sounds associated with each heartbeat from above systole to below diastole during linear cuff deflation. Three repeat BP measurements were taken from 140 healthy subjects (age 21 to 73 years; 62 female and 78 male) by a trained observer, giving 420 measurements. During the BP measurements, the cuff pressure and stethoscope signals were simultaneously recorded digitally to a computer for subsequent analysis. Heartbeats were identified from the oscillometric cuff pressure pulses. The presence of each beat was used to create a time window (1 s, 2000 samples) centered on the oscillometric pulse peak for extracting beat-by-beat stethoscope sounds. A time-frequency two-dimensional matrix was obtained for the stethoscope sounds associated with each beat, and all beats between the manually determined SBPs and DBPs were labeled as "Korotkoff." A convolutional neural network was then used to analyze consistency in sound patterns that were associated with Korotkoff sounds. A 10-fold cross-validation strategy was applied to the stethoscope sounds from all 140 subjects, with the data from ten groups of 14 subjects being analyzed separately, allowing consistency to be evaluated between groups. Next, within-subject variation of the Korotkoff sounds analyzed from the three repeats was quantified, separately for each stethoscope sound beat. There was consistency between folds with no significant differences between groups of 14 subjects (P = 0.09 to P = 0.62). Our results showed that 80.7% beats at SBP and 69.5% at DBP were analyzed as Korotkoff sounds, with significant differences between adjacent beats at systole (13.1%, P = 0.001) and diastole (17.4%, P < 0.001). Results reached stability for SBP (97.8%, at sixth beat below SBP) and DBP (98.1%, at sixth beat above DBP) with no significant differences between adjacent beats (SBP P = 0.74; DBP P = 0.88). There were no significant differences at high-cuff pressures, but at low pressures close to diastole there was a small difference (3.3%, P = 0.02). In addition, greater within subject variability was observed at SBP (21.4%) and DBP (28.9%), with a significant difference between both (P < 0.02). In conclusion, this study has demonstrated that Korotkoff sounds can be consistently identified during the period below SBP and above DBP, but that at systole and diastole there can be substantial variations that are associated with high variation in the three repeat measurements in each subject.

Pathogenesis and Treatment of Cerebral Air Embolism and Associated Disorders.

DTIC Science & Technology

1984-04-01

blades) 12. 7.0, 8.0 and 9.0-mm endotracheal tubes 13. Endotracheal tube stylet 14. Esophageal obturator airway 15. Tracheal suction catheters (14F) 17 r...16. Nasogastric suction tube and Tumee syringe 17. Tincture of Benzoin 18. 2-in waterproof tape 19. Precordial stethoscope 20. Esophageal stethoscope...be justified. If an endotracheal tube cannot be passed, an esophageal obturator airway may be useful. If such an airway Is used, the newer models

Two-modality γ detection of blood volume by camera imaging and nonimaging stethoscope for kinetic studies of cardiovascular control in nuclear medicine

NASA Astrophysics Data System (ADS)

Eclancher, Bernard; Chambron, Jacques; Dumitresco, Barbu; Karman, Miklos; Pszota, Agnes; Simon, Atilla; Didon-Poncelet, Anna; Demangeat, Jean

2002-04-01

The quantification of rapid hemodynamic reactions to wide and slow breathing movements has been performed, by two modalities (gamma) -left ventriculography of 99mTc-labeled blood volume, in anterior oblique incidence on standing and even exercising healthy volunteers and cardiac patients. A highly sensitive stethoscope delivered whole (gamma) -counts acquired at 30 msec intervals in a square field of view including the left ventricle, in a one dimensional low resolution imaging mode for beat to beat analysis. A planar 2D (gamma) -camera imaging of the same cardiac area was then performed without cardiac gating for alternate acquisitions during deep inspiration and deep expiration, completed by a 3D MRI assessment of the stethoscope detection field. Young healthy volunteers displayed wide variations of diastolic times and stroke volumes, as a result of enhanced baroreflex control, together with +/- 16% variations of the stethoscope's background blood volume counts. Any of the components of these responses were shifted, abolished or even inverted as a result of either obesity, hypertension, aging or cardiac pathologies. The assessment of breathing control of the cardiovascular system by the beat to beat (gamma) -ventriculography combined with nuclear 2D and 3D MRI imaging is a kinetic method allowing the detection of functional anomalies in still ambulatory patients.

Experimental validation of the tuneable diaphragm effect in modern acoustic stethoscopes.

PubMed

Nowak, Karolina M; Nowak, Lukasz J

2017-09-01

The force with which the diaphragm chestpiece of a stethoscope is pressed against the body of a patient during an auscultation examination introduces the initial stress and deformation to the diaphragm and the underlying tissues, thus altering the acoustic parameters of the sound transmission path. If the examination is performed by an experienced physician, he will intuitively adjust the amount of the force in order to achieve the optimal sound quality. However, in case of becoming increasingly popular auto-diagnosis and telemedicine auscultation devices with no such feedback mechanisms, the question arises regarding the influence of the possible force mismatch on the parameters of the recorded signal. The present study describes the results of the experimental investigations on the relation between pressure applied to the chestpiece of a stethoscope and parameters of the transmitted bioacoustic signals. The experiments were carried out using various stethoscopes connected to a force measurement system, which allowed to maintain fixed pressure during auscultation examinations. The signals were recorded during examinations of different volunteers, at various auscultation sites. The obtained results reveal strong individual and auscultation-site variability. It is concluded that the underlying tissue deformation is the primary factor that alters the parameters of the recorded signals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Performance Evaluation of Heart Sound Cancellation in FPGA Hardware Implementation for Electronic Stethoscope

PubMed Central

Chao, Chun-Tang

2014-01-01

This paper presents the design and evaluation of the hardware circuit for electronic stethoscopes with heart sound cancellation capabilities using field programmable gate arrays (FPGAs). The adaptive line enhancer (ALE) was adopted as the filtering methodology to reduce heart sound attributes from the breath sounds obtained via the electronic stethoscope pickup. FPGAs were utilized to implement the ALE functions in hardware to achieve near real-time breath sound processing. We believe that such an implementation is unprecedented and crucial toward a truly useful, standalone medical device in outpatient clinic settings. The implementation evaluation with one Altera cyclone II–EP2C70F89 shows that the proposed ALE used 45% resources of the chip. Experiments with the proposed prototype were made using DE2-70 emulation board with recorded body signals obtained from online medical archives. Clear suppressions were observed in our experiments from both the frequency domain and time domain perspectives. PMID:24790573

Determination of heart rate variability with an electronic stethoscope.

PubMed

Kamran, Haroon; Naggar, Isaac; Oniyuke, Francisca; Palomeque, Mercy; Chokshi, Priya; Salciccioli, Louis; Stewart, Mark; Lazar, Jason M

2013-02-01

Heart rate variability (HRV) is widely used to characterize cardiac autonomic function by measuring beat-to-beat alterations in heart rate. Decreased HRV has been found predictive of worse cardiovascular (CV) outcomes. HRV is determined from time intervals between QRS complexes recorded by electrocardiography (ECG) for several minutes to 24 h. Although cardiac auscultation with a stethoscope is performed routinely on patients, the human ear cannot detect heart sound time intervals. The electronic stethoscope digitally processes heart sounds, from which cardiac time intervals can be obtained. Accordingly, the objective of this study was to determine the feasibility of obtaining HRV from electronically recorded heart sounds. We prospectively studied 50 subjects with and without CV risk factors/disease and simultaneously recorded single lead ECG and heart sounds for 2 min. Time and frequency measures of HRV were calculated from R-R and S1-S1 intervals and were compared using intra-class correlation coefficients (ICC). The majority of the indices were strongly correlated (ICC 0.73-1.0), while the remaining indices were moderately correlated (ICC 0.56-0.63). In conclusion, we found HRV measures determined from S1-S1 are in agreement with those determined by single lead ECG, and we demonstrate and discuss differences in the measures in detail. In addition to characterizing cardiac murmurs and time intervals, the electronic stethoscope holds promise as a convenient low-cost tool to determine HRV in the hospital and outpatient settings as a practical extension of the physical examination.

A low-cost 3-D printed stethoscope connected to a smartphone.

PubMed

Aguilera-Astudillo, Carlos; Chavez-Campos, Marx; Gonzalez-Suarez, Alan; Garcia-Cordero, Jose L

2016-08-01

We demonstrate the fabrication of a digital stethoscope using a 3D printer and commercial off-the-shelf electronics. A chestpiece consists of an electret microphone embedded into the drum of a 3D printed chestpiece. An electronic dongle amplifies the signal from the microphone and reduces any external noise. It also adjusts the signal to the voltages accepted by the smartphones headset jack. A graphical user interface programmed in Android displays the signals processed by the dongle. The application also saves the processed signal and sends it to a physician.

Infrasonic Stethoscope for Monitoring Physiological Processes

NASA Technical Reports Server (NTRS)

Zuckerwar, Allan J. (Inventor); Shams, Qamar A. (Inventor); Dimarcantonio, Albert L. (Inventor)

2018-01-01

An infrasonic stethoscope for monitoring physiological processes of a patient includes a microphone capable of detecting acoustic signals in the audible frequency bandwidth and in the infrasonic bandwidth (0.03 to 1000 Hertz), a body coupler attached to the body at a first opening in the microphone, a flexible tube attached to the body at a second opening in the microphone, and an earpiece attached to the flexible tube. The body coupler is capable of engagement with a patient to transmit sounds from the person, to the microphone and then to the earpiece.

Infrasonic Stethoscope for Monitoring Physiological Processes

NASA Technical Reports Server (NTRS)

Zuckerwar, Allan J. (Inventor); Shams, Qamar A. (Inventor); Dimarcantonio, Albert L. (Inventor)

2016-01-01

An infrasonic stethoscope for monitoring physiological processes of a patient includes a microphone capable of detecting acoustic signals in the audible frequency bandwidth and in the infrasonic bandwidth (0.03 to 1000 Hertz), a body coupler attached to the body at a first opening in the microphone, a flexible tube attached to the body at a second opening in the microphone, and an earpiece attached to the flexible tube. The body coupler is capable of engagement with a patient to transmit sounds from the person, to the microphone and then to the earpiece.

Validation of heart and lung teleauscultation on an Internet-based system.

PubMed

Fragasso, Gabriele; De Benedictis, Marialuisa; Palloshi, Altin; Moltrasio, Marco; Cappelletti, Alberto; Carlino, Mauro; Marchisi, Angelo; Pala, Mariagrazia; Alfieri, Ottavio; Margonato, Alberto

2003-11-01

The feasibility and accuracy of an Internet-based system for teleauscultation was evaluated in 103 cardiac patients, who were auscultated by the same cardiologist with a conventional stethoscope and with an Internet-based method, using an electronic stethoscope and transmitting heart and lung sounds between computer work stations. In 92% of patients, the results of electronic and acoustic auscultation coincided, indicating that teleauscultation may be considered a reliable method for assessing cardiac patients and could, therefore, be adopted in the context of comprehensive telecare programs.

A Wireless Electronic Esophageal Stethoscope for Continuous Monitoring of Cardiovascular and Respiratory Systems during Anaesthesia

PubMed Central

Parsaei, H.; Vakily, A.; Shafiei, A.M.

2017-01-01

Background: The basic requirements for monitoring anesthetized patients during surgery are assessing cardiac and respiratory function. Esophageal stethoscopes have been developed for this purpose, but these devices may not provide clear heart and lung sound due to existence of various noises in operating rooms. In addition, the stethoscope is not applicable for continues monitoring, and it is unsuitable for observing inaccessible patients in some conditions such as during CT scan. Objective: A wireless electronic esophageal stethoscope is designed for continues auscultation of heart and lung sounds in anesthetized patients. The system consists of a transmitter and a receiver. The former acquires, amplifies and transmits the acquired sound signals to the latter via a frequency modulation transmitter. The receiver demodulates, amplifies, and delivers the received signal to a headphone to be heard by anesthesiologist. Results: The usability and effectiveness of the designed system was qualitatively evaluated by 5 anesthesiologists in Namazi Hospital and Shahid Chamran Hospital, Shiraz, Iran on 30 patients in several operating rooms in different conditions; e.g., when electro surgery instruments are working. Fortunately, the experts on average ranked good quality for the heard heart and lung sounds and very good on the user friendly being of the instrument. Conclusion: Evaluation results demonstrate that the developed system is capable of capturing and transmitting heart and lung sounds successfully. Therefore, it can be used to continuously monitor anesthetized patients’ cardiac and respiratory function. Since via the instrument wireless auscultation is possible, it could be suitable for observing inaccessible patients in several conditions such as during CT scan. PMID:28451580

Clinical evaluation of the 3M Littmann Electronic Stethoscope Model 3200 in 150 cats.

PubMed

Blass, Keith A; Schober, Karsten E; Bonagura, John D; Scansen, Brian A; Visser, Lance C; Lu, Jennifer; Smith, Danielle N; Ward, Jessica L

2013-10-01

Detection of murmurs and gallops may help to identify cats with heart disease. However, auscultatory findings may be subject to clinically relevant observer variation. The objective of this study was to evaluate an electronic stethoscope (ES) in cats. We hypothesized that the ES would perform at least as well as a conventional stethoscope (CS) in the detection of abnormal heart sounds. One hundred and fifty consecutive cats undergoing echocardiography were enrolled prospectively. Cats were ausculted with a CS (WA Tycos Harvey Elite) by two observers, and heart sounds were recorded digitally using an ES (3M Littmann Stethoscope Model 3200) for off-line analysis. Echocardiography was used as the clinical standard method for validation of auscultatory findings. Additionally, digital recordings (DRs) were assessed by eight independent observers with various levels of expertise, and compared using interclass correlation and Cohen's weighted kappa analyses. Using the CS, a heart murmur (n = 88 cats) or gallop sound (n = 17) was identified in 105 cats, whereas 45 cats lacked abnormal heart sounds. There was good total agreement (83-90%) between the two observers using the CS. In contrast, there was only moderate agreement (P <0.001) between results from the CS and the DRs for murmurs, and poor agreement for gallops. The CS was more sensitive compared with the DRs with regard to murmurs and gallops. Agreement among the eight observers was good-to-excellent for murmur detection (81%). In conclusion, DRs made with the ES are less sensitive but comparably specific to a CS at detecting abnormal heart sounds in cats.

Randomised controlled trial of intrapartum fetal heart rate monitoring.

PubMed

Mahomed, K; Nyoni, R; Mulambo, T; Kasule, J; Jacobus, E

1994-02-19

To compare effectiveness of different methods of monitoring intrapartum fetal heart rate. Prospective randomised controlled trial. Referral maternity hospital, Harare, Zimbabwe. 1255 women who were 37 weeks or more pregnant with singleton cephalic presentation and normal fetal heart rate before entry into study. Intermittent monitoring of fetal heart rate by electronic monitoring, Doppler ultrasound, use of Pinard stethoscope by a research midwife, or routine use of Pinard stethoscope by attending midwife. Abnormal fetal heart rate patterns, need for operative delivery for fetal distress, neonatal mortality, Apgar scores, admission to neonatal unit, neonatal seizures, and hypoxic ischaemic encephalopathy. Abnormalities in fetal heart rate were detected in 54% (172/318) of the electronic monitoring group, 32% (100/312) of the ultrasonography group, 15% (47/310) of the Pinard stethoscope group, and 9% (28/315) of the routine monitoring group. Caesarean sections were performed for 28% (89%), 24% (76), 10% (32), and 15% (46) of the four groups respectively. Neonatal outcome was best in the ultrasonography group: hypoxic ischaemic encephalopathy occurred in two, one, seven, and 10 cases in the four groups respectively; neonatal seizures occurred only in the last two groups (six and nine cases respectively); and deaths occurred in eight, two, five, and nine cases respectively. Abnormalities in fetal heart rate were more reliably detected by Doppler ultrasonography than with Pinard stethoscope, and its use resulted in good perinatal outcome. The use of relatively cheap ultrasound monitors should be further evaluated and promoted in obstetric units caring for high risk pregnancies in developing countries with scarce resources.

Randomised controlled trial of intrapartum fetal heart rate monitoring.

PubMed Central

Mahomed, K.; Nyoni, R.; Mulambo, T.; Kasule, J.; Jacobus, E.

1994-01-01

OBJECTIVE--To compare effectiveness of different methods of monitoring intrapartum fetal heart rate. DESIGN--Prospective randomised controlled trial. SETTING--Referral maternity hospital, Harare, Zimbabwe. SUBJECTS--1255 women who were 37 weeks or more pregnant with singleton cephalic presentation and normal fetal heart rate before entry into study. INTERVENTIONS--Intermittent monitoring of fetal heart rate by electronic monitoring, Doppler ultrasound, use of Pinard stethoscope by a research midwife, or routine use of Pinard stethoscope by attending midwife. MAIN OUTCOME MEASURES--Abnormal fetal heart rate patterns, need for operative delivery for fetal distress, neonatal mortality, Apgar scores, admission to neonatal unit, neonatal seizures, and hypoxic ischaemic encephalopathy. RESULTS--Abnormalities in fetal heart rate were detected in 54% (172/318) of the electronic monitoring group, 32% (100/312) of the ultrasonography group, 15% (47/310) of the Pinard stethoscope group, and 9% (28/315) of the routine monitoring group. Caesarean sections were performed for 28% (89%), 24% (76), 10% (32), and 15% (46) of the four groups respectively. Neonatal outcome was best in the ultrasonography group: hypoxic ischaemic encephalopathy occurred in two, one, seven, and 10 cases in the four groups respectively; neonatal seizures occurred only in the last two groups (six and nine cases respectively); and deaths occurred in eight, two, five, and nine cases respectively. CONCLUSIONS--Abnormalities in fetal heart rate were more reliably detected by Doppler ultrasonography than with Pinard stethoscope, and its use resulted in good perinatal outcome. The use of relatively cheap ultrasound monitors should be further evaluated and promoted in obstetric units caring for high risk pregnancies in developing countries with scarce resources. PMID:8136665

Continuous monitoring of blood pressure by analyzing the blood flow sound of arteriovenous fistula in hemodialysis patients.

PubMed

Kamijo, Yuka; Kanda, Eiichiro; Horiuchi, Hayato; Kounoue, Noriyuki; Ono, Keisuke; Maeda, Keizo; Yanai, Akane; Honda, Kazuya; Tsujimoto, Ryuji; Yanagi, Mai; Ishibashi, Yoshitaka; Yoshida, Masayuki

2018-06-01

Patients with end-stage renal disease undergoing hemodialysis (HD) have an elevated risk of cardiovascular disease-related morbidity and mortality. To prevent from such a life-threatening event, the continuous blood pressure (BP) monitoring system may contribute to detect BP decline in early stages and may help to do appropriate disposal. Our research team has introduced an electronic stethoscope (Asahi Kasei Co, Ltd., Tokyo, Japan), which translates sound intensity of Arteriovenous Fistula (AVF) to BP data using the technique of Fourier transformation that can predict continuous BP non-invasively. This study, we investigated whether electronic stethoscope-guided estimated BP (e-BP) would actually reflect systolic BP measured by sphygmomanometer (s-BP), and whether e-BP could predict fall of BP during HD. Twenty-six patients who underwent HD treatment in our hospital were evaluated prospectively. We obtained sound intensity data from the electronic stethoscope which was equipped with the return line of HD. Then, the data were translated into e-BP data to be compared with s-BP. Correlation of total of 315 data sets obtained from each method was examined. An accuracy of diagnosis of intra-dialytic hypotension (IDH) was evaluated. Total of 315 data sets were obtained. A close correlation was observed between e-BP and s-BP (r = 0.887, p < 0.0001). Sensitivity and positive predictive value of predicted-BP for detection of IDH was 90 and 81.3%, respectively. Electronic stethoscope-guided BP measurement would be helpful for real-time diagnosis of BP fall in HD patients. Further investigations are needed.

Improved auscultation skills in paramedic students using a modified stethoscope.

PubMed

Simon, Erin L; Lecat, Paul J; Haller, Nairmeen A; Williams, Carolyn J; Martin, Scott W; Carney, John A; Pakiela, John A

2012-12-01

The Ventriloscope® (Lecat's SimplySim, Tallmadge, OH) is a modified stethoscope used as a simulation training device for auscultation. To test the effectiveness of the Ventriloscope as a training device in teaching heart and lung auscultatory findings to paramedic students. A prospective, single-hospital study conducted in a paramedic-teaching program. The standard teaching group learned heart and lung sounds via audiocassette recordings and lecture, whereas the intervention group utilized the modified stethoscope in conjunction with patient volunteers. Study subjects took a pre-test, post-test, and a follow-up test to measure recognition of heart and lung sounds. The intervention group included 22 paramedic students and the standard group included 18 paramedic students. Pre-test scores did not differ using two-sample t-tests (standard group: t [16]=-1.63, p=0.12) and (intervention group: t [20]=-1.17, p=0.26). Improvement in pre-test to post-test scores was noted within each group (standard: t [17]=2.43, p=0.03; intervention: t [21]=4.81, p<0.0001). Follow-up scores for the standard group were not different from pre-test scores of 16.06 (t [17]=0.94, p=0.36). However, follow-up scores for the intervention group significantly improved from their respective pre-test score of 16.05 (t [21]=2.63, p=0.02). Simulation training using a modified stethoscope in conjunction with standardized patients allows for realistic learning of heart and lung sounds. This technique of simulation training achieved proficiency and better retention of heart and lung sounds in a safe teaching environment. Copyright © 2012 Elsevier Inc. All rights reserved.

The 200th anniversary of the stethoscope: Can this low-tech device survive in the high-tech 21st century?

PubMed

Bank, Ivan; Vliegen, Hubert W; Bruschke, Albert V G

2016-12-14

In 1816, Laennec discovered that auscultation of the heart and lungs could effectively be performed by placing a hollow cylinder (initially made of a roll of paper) between the chest of the patient and the ear of the examiner. This was the first step in the development of the stethoscope, which was a breakthrough in the diagnosis and management of cardiac and pulmonary patients. Technical improvements of the stethoscope followed and in cardiac patients auscultation soon became a major diagnostic tool. In the second half of the 20th century, new powerful non-invasive diagnostic modalities were developed and the interest in auscultation declined. As a result, the auscultatory skills of students and physicians at all levels of training decreased to a disappointingly low level. We now must decide whether we should stimulate the use of and proficiency in auscultation or if we should accept the further decline and eventual abolishment of this component of the physical examination. Reviewing the literature and taking into consideration the setting in which the patients are presented, including the availability of advanced diagnostic facilities, we conclude that the time-honoured stethoscope, in spite of its limitations, still has potential as a patient-friendly, effective, and economical instrument in medical practice. However, new initiatives are required to train students, physicians and allied health professionals in cardiac auscultation to avoid misinterpretations that may harm the patients and generate extra costs. To be successful such programs will require wide support from the medical community. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Music-of-light stethoscope: a demonstration of the photoacoustic effect

NASA Astrophysics Data System (ADS)

Nikitichev, D. I.; Xia, W.; Hill, E.; Mosse, C. A.; Perkins, T.; Konyn, K.; Ourselin, S.; Desjardins, A. E.; Vercauteren, T.

2016-07-01

In this paper we present a system aimed at demonstrating the photoacoustic (PA) effect for educational purposes. PA imaging is a hybrid imaging modality that requires no contrast agent and has a great potential for spine and brain lesion characterisation, breast cancer and blood flow monitoring notably in the context of fetal surgery. It relies on combining light excitation with ultrasound reception. Our brief was to present and explain PA imaging in a public-friendly way suitable for a variety of ages and backgrounds. We developed a simple, accessible demonstration unit using readily available materials. We used a modulated light emitting diode (LED) torch and an electronic stethoscope. The output of a music player was used for light modulation and the chest piece of the stethoscope covered by a black tape was used as an absorbing target and an enclosed chamber. This demonstration unit was presented to the public at the Bloomsbury Festival On Light in October 2015. Our stall was visited by over 100 people of varying ages. Twenty families returned in-depth evaluation questionnaires, which show that our explanations of the photoacoustic effect were well understood. Their interest in biomedical engineering was increased.

Music-of-light stethoscope: a demonstration of the photoacoustic effect

PubMed Central

Nikitichev, D I; Xia, W; Hill, E; Mosse, C A; Perkins, T; Konyn, K; Ourselin, S; Desjardins, A E; Vercauteren, T

2016-01-01

Abstract In this paper we present a system aimed at demonstrating the photoacoustic (PA) effect for educational purposes. PA imaging is a hybrid imaging modality that requires no contrast agent and has a great potential for spine and brain lesion characterisation, breast cancer and blood flow monitoring notably in the context of fetal surgery. It relies on combining light excitation with ultrasound reception. Our brief was to present and explain PA imaging in a public-friendly way suitable for a variety of ages and backgrounds. We developed a simple, accessible demonstration unit using readily available materials. We used a modulated light emitting diode (LED) torch and an electronic stethoscope. The output of a music player was used for light modulation and the chest piece of the stethoscope covered by a black tape was used as an absorbing target and an enclosed chamber. This demonstration unit was presented to the public at the Bloomsbury Festival On Light in October 2015. Our stall was visited by over 100 people of varying ages. Twenty families returned in-depth evaluation questionnaires, which show that our explanations of the photoacoustic effect were well understood. Their interest in biomedical engineering was increased. PMID:29249838

Soft Stethoscope for Detecting Asthma Wheeze in Young Children

PubMed Central

Yu, Chun; Tsai, Tzu-Hsiu; Huang, Shi-Ing; Lin, Chii-Wann

2013-01-01

Asthma is a chronic disease that is commonly suffered by children. Asthmatic children have a lower quality of life than other children. Physicians and pediatricians recommend that parents record the frequency of attacks and their symptoms to help manage their children's asthma. However, the lack of a convenient device for monitoring the asthmatic condition leads to the difficulties in managing it, especially when it is suffered by young children. This work develops a wheeze detection system for use at home. A small and soft stethoscope was used to collect the respiratory sound. The wheeze detection algorithm was the Adaptive Respiratory Spectrum Correlation Coefficient (RSACC) algorithm, which has the advantages of high sensitivity/specificity and a low computational requirement. Fifty-nine sound files from eight young children (one to seven years old) were collected in the emergency room and analyzed. The results revealed that the system provided 88% sensitivity and 94% specificity in wheeze detection. In conclusion, this small soft stethoscope can be easily used on young children. A noisy environment does not affect the effectiveness of the system in detecting wheeze. Hence, the system can be used at home by parents who wish to evaluate and manage the asthmatic condition of their children. PMID:23744030

Soft stethoscope for detecting asthma wheeze in young children.

PubMed

Yu, Chun; Tsai, Tzu-Hsiu; Huang, Shi-Ing; Lin, Chii-Wann

2013-06-06

Asthma is a chronic disease that is commonly suffered by children. Asthmatic children have a lower quality of life than other children. Physicians and pediatricians recommend that parents record the frequency of attacks and their symptoms to help manage their children's asthma. However, the lack of a convenient device for monitoring the asthmatic condition leads to the difficulties in managing it, especially when it is suffered by young children. This work develops a wheeze detection system for use at home. A small and soft stethoscope was used to collect the respiratory sound. The wheeze detection algorithm was the Adaptive Respiratory Spectrum Correlation Coefficient (RSACC) algorithm, which has the advantages of high sensitivity/specificity and a low computational requirement. Fifty-nine sound files from eight young children (one to seven years old) were collected in the emergency room and analyzed. The results revealed that the system provided 88% sensitivity and 94% specificity in wheeze detection. In conclusion, this small soft stethoscope can be easily used on young children. A noisy environment does not affect the effectiveness of the system in detecting wheeze. Hence, the system can be used at home by parents who wish to evaluate and manage the asthmatic condition of their children.

[Computer-aided Diagnosis and New Electronic Stethoscope].

PubMed

Huang, Mei; Liu, Hongying; Pi, Xitian; Ao, Yilu; Wang, Zi

2017-05-30

Auscultation is an important method in early-diagnosis of cardiovascular disease and respiratory system disease. This paper presents a computer-aided diagnosis of new electronic auscultation system. It has developed an electronic stethoscope based on condenser microphone and the relevant intelligent analysis software. It has implemented many functions that combined with Bluetooth, OLED, SD card storage technologies, such as real-time heart and lung sounds auscultation in three modes, recording and playback, auscultation volume control, wireless transmission. The intelligent analysis software based on PC computer utilizes C# programming language and adopts SQL Server as the background database. It has realized play and waveform display of the auscultation sound. By calculating the heart rate, extracting the characteristic parameters of T1, T2, T12, T11, it can analyze whether the heart sound is normal, and then generate diagnosis report. Finally the auscultation sound and diagnosis report can be sent to mailbox of other doctors, which can carry out remote diagnosis. The whole system has features of fully function, high portability, good user experience, and it is beneficial to promote the use of electronic stethoscope in the hospital, at the same time, the system can also be applied to auscultate teaching and other occasions.

Music-of-light stethoscope: a demonstration of the photoacoustic effect.

PubMed

Nikitichev, D I; Xia, W; Hill, E; Mosse, C A; Perkins, T; Konyn, K; Ourselin, S; Desjardins, A E; Vercauteren, T

2016-07-01

In this paper we present a system aimed at demonstrating the photoacoustic (PA) effect for educational purposes. PA imaging is a hybrid imaging modality that requires no contrast agent and has a great potential for spine and brain lesion characterisation, breast cancer and blood flow monitoring notably in the context of fetal surgery. It relies on combining light excitation with ultrasound reception. Our brief was to present and explain PA imaging in a public-friendly way suitable for a variety of ages and backgrounds. We developed a simple, accessible demonstration unit using readily available materials. We used a modulated light emitting diode (LED) torch and an electronic stethoscope. The output of a music player was used for light modulation and the chest piece of the stethoscope covered by a black tape was used as an absorbing target and an enclosed chamber. This demonstration unit was presented to the public at the Bloomsbury Festival On Light in October 2015. Our stall was visited by over 100 people of varying ages. Twenty families returned in-depth evaluation questionnaires, which show that our explanations of the photoacoustic effect were well understood. Their interest in biomedical engineering was increased.

Characterization of Cardiac Time Intervals in Healthy Bonnet Macaques (Macaca radiata) by Using an Electronic Stethoscope

PubMed Central

Kamran, Haroon; Salciccioli, Louis; Pushilin, Sergei; Kumar, Paraag; Carter, John; Kuo, John; Novotney, Carol; Lazar, Jason M

2011-01-01

Nonhuman primates are used frequently in cardiovascular research. Cardiac time intervals derived by phonocardiography have long been used to assess left ventricular function. Electronic stethoscopes are simple low-cost systems that display heart sound signals. We assessed the use of an electronic stethoscope to measure cardiac time intervals in 48 healthy bonnet macaques (age, 8 ± 5 y) based on recorded heart sounds. Technically adequate recordings were obtained from all animals and required 1.5 ± 1.3 min. The following cardiac time intervals were determined by simultaneously recording acoustic and single-lead electrocardiographic data: electromechanical activation time (QS1), electromechanical systole (QS2), the time interval between the first and second heart sounds (S1S2), and the time interval between the second and first sounds (S2S1). QS2 was correlated with heart rate, mean arterial pressure, diastolic blood pressure, and left ventricular ejection time determined by using echocardiography. S1S2 correlated with heart rate, mean arterial pressure, diastolic blood pressure, left ventricular ejection time, and age. S2S1 correlated with heart rate, mean arterial pressure, diastolic blood pressure, systolic blood pressure, and left ventricular ejection time. QS1 did not correlate with any anthropometric or echocardiographic parameter. The relation S1S2/S2S1 correlated with systolic blood pressure. On multivariate analyses, heart rate was the only independent predictor of QS2, S1S2, and S2S1. In conclusion, determination of cardiac time intervals is feasible and reproducible by using an electrical stethoscope in nonhuman primates. Heart rate is a major determinant of QS2, S1S2, and S2S1 but not QS1; regression equations for reference values for cardiac time intervals in bonnet macaques are provided. PMID:21439218

In defence of auscultation: a glorious future?

PubMed Central

Thompson, W Reid

2017-01-01

Auscultation of the heart using a simple stethoscope continues to be a central aspect of the cardiovascular examination despite declining proficiency and availability of competing technologies such as hand-held ultrasound. In the ears and mind of a trained cardiologist, heart sounds can provide important information to help screen for certain diseases such as valvar lesions and many congenital defects. Using emerging technology, auscultation is poised to undergo a transformation that will simultaneously improve the teaching and evaluation of this important clinical skill and create a new generation of smart stethoscopes, capable of assisting the clinician in quickly and confidently screening for heart disease. These developments have important implications for global health, screening of athletes and recognition of congenital heart disease. PMID:28243316

Comparison of the measurement of heart rate in adult free-range chickens (Gallus domesticus) by auscultation and electrocardiography.

PubMed

Smith, C F; Gavaghan, B J; McSweeney, D; Powell, V; Lisle, A

2014-12-01

To compare the heart rates of adult free-range chickens (Gallus domesticus) measured by auscultation with a stethoscope with those measured simultaneously using electrocardiography (ECG). With each bird in a standing position, estimation of the heart rate was performed by placing a mark on paper for every 4 beats for roosters and 8 beats for hens as detected by auscultation over 30 s, while simultaneous ECG was performed. Heart rates measured by auscultation showed a high correlation (r = 0.97) with those measured by ECG. There was a high correlation between the heart rates of adult free-range chickens measured by auscultation with a stethoscope and those measured simultaneously using ECG. © 2014 Australian Veterinary Association.

Acoustics based assessment of respiratory diseases using GMM classification.

PubMed

Mayorga, P; Druzgalski, C; Morelos, R L; Gonzalez, O H; Vidales, J

2010-01-01

The focus of this paper is to present a method utilizing lung sounds for a quantitative assessment of patient health as it relates to respiratory disorders. In order to accomplish this, applicable traditional techniques within the speech processing domain were utilized to evaluate lung sounds obtained with a digital stethoscope. Traditional methods utilized in the evaluation of asthma involve auscultation and spirometry, but utilization of more sensitive electronic stethoscopes, which are currently available, and application of quantitative signal analysis methods offer opportunities of improved diagnosis. In particular we propose an acoustic evaluation methodology based on the Gaussian Mixed Models (GMM) which should assist in broader analysis, identification, and diagnosis of asthma based on the frequency domain analysis of wheezing and crackles.

Bronchitis

MedlinePlus

... you and listen to your chest with a stethoscope for signs of wheezing and congestion. In addition ... harder time recovering from acute bronchitis and other respiratory infections. Smoking causes lung damage in many ways. ...

Pulmonary nocardiosis

MedlinePlus

... you and listen to your lungs using a stethoscope. You may have abnormal lung sounds, called crackles. ... returning. Alternative Names Nocardiosis - pulmonary; Mycetoma; Nocardia Images Respiratory system References Southwick FS. Nocardiosis. In: Goldman L, ...

Control Software

NASA Technical Reports Server (NTRS)

1997-01-01

Real-Time Innovations, Inc. (RTI) collaborated with Ames Research Center, the Jet Propulsion Laboratory and Stanford University to leverage NASA research to produce ControlShell software. RTI is the first "graduate" of Ames Research Center's Technology Commercialization Center. The ControlShell system was used extensively on a cooperative project to enhance the capabilities of a Russian-built Marsokhod rover being evaluated for eventual flight to Mars. RTI's ControlShell is complex, real-time command and control software, capable of processing information and controlling mechanical devices. One ControlShell tool is StethoScope. As a real-time data collection and display tool, StethoScope allows a user to see how a program is running without changing its execution. RTI has successfully applied its software savvy in other arenas, such as telecommunications, networking, video editing, semiconductor manufacturing, automobile systems, and medical imaging.

Collapsed lung (pneumothorax)

MedlinePlus

... provider will listen to your breathing with a stethoscope. If you have a collapsed lung, there are ... rupture, chest x-ray Pneumothorax - chest x-ray Respiratory system Chest tube insertion - series Pneumothorax - series References ...

Meconium aspiration syndrome

MedlinePlus

... will listen to the infant's chest with a stethoscope and may hear abnormal breath sounds, especially coarse, ... care - meconium Images Meconium References Crowley MA. Neonatal respiratory disorders. In: Martin RJ, Fanaroff AA, Walsh MC, ...

Doctor, Teacher, and Stethoscope: Neural Representation of Different Types of Semantic Relations.

PubMed

Xu, Yangwen; Wang, Xiaosha; Wang, Xiaoying; Men, Weiwei; Gao, Jia-Hong; Bi, Yanchao

2018-03-28

Concepts can be related in many ways. They can belong to the same taxonomic category (e.g., "doctor" and "teacher," both in the category of people) or be associated with the same event context (e.g., "doctor" and "stethoscope," both associated with medical scenarios). How are these two major types of semantic relations coded in the brain? We constructed stimuli from three taxonomic categories (people, manmade objects, and locations) and three thematic categories (school, medicine, and sports) and investigated the neural representations of these two dimensions using representational similarity analyses in human participants (10 men and nine women). In specific regions of interest, the left anterior temporal lobe (ATL) and the left temporoparietal junction (TPJ), we found that, whereas both areas had significant effects of taxonomic information, the taxonomic relations had stronger effects in the ATL than in the TPJ ("doctor" and "teacher" closer in ATL neural activity), with the reverse being true for thematic relations ("doctor" and "stethoscope" closer in TPJ neural activity). A whole-brain searchlight analysis revealed that widely distributed regions, mainly in the left hemisphere, represented the taxonomic dimension. Interestingly, the significant effects of the thematic relations were only observed after the taxonomic differences were controlled for in the left TPJ, the right superior lateral occipital cortex, and other frontal, temporal, and parietal regions. In summary, taxonomic grouping is a primary organizational dimension across distributed brain regions, with thematic grouping further embedded within such taxonomic structures. SIGNIFICANCE STATEMENT How are concepts organized in the brain? It is well established that concepts belonging to the same taxonomic categories (e.g., "doctor" and "teacher") share neural representations in specific brain regions. How concepts are associated in other manners (e.g., "doctor" and "stethoscope," which are thematically related) remains poorly understood. We used representational similarity analyses to unravel the neural representations of these different types of semantic relations by testing the same set of words that could be differently grouped by taxonomic categories or by thematic categories. We found that widely distributed brain areas primarily represented taxonomic categories, with the thematic categories further embedded within the taxonomic structure. Copyright © 2018 the authors 0270-6474/18/383303-15$15.00/0.

Poststreptococcal glomerulonephritis (GN)

MedlinePlus

... following: Decreased urine output Rust-colored urine Swelling (edema), general swelling, swelling of the abdomen, swelling of ... A physical examination shows swelling (edema), especially in the face. ... to the heart and lungs with a stethoscope. Blood pressure ...

Apgar score

MedlinePlus

... infant cries well, the respiratory score is 2. Heart rate is evaluated by stethoscope. This is the most important assessment: If there is no heartbeat, the infant scores 0 for heart rate. If heart rate is less than 100 ...

Rene Theophile Hyacinthe Laënnec (1781–1826): The Man Behind the Stethoscope

PubMed Central

Roguin, Ariel

2006-01-01

Rene Theophile Hyacinthe Laënnec (1781–1826) was a French physician who, in 1816, invented the stethoscope. Using this new instrument, he investigated the sounds made by the heart and lungs and determined that his diagnoses were supported by the observations made during autopsies. Laënnec later published the first seminal work on the use of listening to body sounds, De L’auscultation Mediate (On Mediate Auscultation). Laënnec is considered the father of clinical auscultation and wrote the first descriptions of bronchiectasis and cirrhosis and also classified pulmonary conditions such as pneumonia, bronchiectasis, pleurisy, emphysema, pneumothorax, phthisis and other lung diseases from the sounds he heard with his invention. Laënnec perfected the art of physical examination of the chest and introduced many clinical terms still used today. PMID:17048358

Fetal evaluation for transport by ultrasound performed by air medical teams: A case series.

PubMed

Polk, James D; Merlino, James I; Kovach, Betty L; Mancuso, Charlene; Fallon, William F

2004-01-01

The air medical team has limited options when evaluating the obstetrical patient and assessing fetal health during air transport to a high-risk obstetrical unit. Traditionally, physical examination and a Doppler stethoscope have been used to determine fetal heart rates and movement. However, with the advent of portable ultrasound technology, new information about the mother and child are available to the air medical crew. The Fetal Evaluation for Transport with Ultrasound (FETUS) is a screening examination that consists of an evaluation of the fetal heart rate, position, and movement and general condition of the placenta. The examination can be repeated in flight with no acoustic distortion from rotor noise. The additional information can be advantageous when transport decisions need to be made or when conditions do not allow Doppler stethoscope use.

Sensor system for heart sound biomonitor

NASA Astrophysics Data System (ADS)

Maple, Jarrad L.; Hall, Leonard T.; Agzarian, John; Abbott, Derek

1999-09-01

Heart sounds can be utilized more efficiently by medical doctors when they are displayed visually, rather than through a conventional stethoscope. A system whereby a digital stethoscope interfaces directly to a PC will be directly along with signal processing algorithms, adopted. The sensor is based on a noise cancellation microphone, with a 450 Hz bandwidth and is sampled at 2250 samples/sec with 12-bit resolution. Further to this, we discuss for comparison a piezo-based sensor with a 1 kHz bandwidth. A major problem is that the recording of the heart sound into these devices is subject to unwanted background noise which can override the heart sound and results in a poor visual representation. This noise originates from various sources such as skin contact with the stethoscope diaphragm, lung sounds, and other surrounding sounds such as speech. Furthermore we demonstrate a solution using 'wavelet denoising'. The wavelet transform is used because of the similarity between the shape of wavelets and the time-domain shape of a heartbeat sound. Thus coding of the waveform into the wavelet domain is achieved with relatively few wavelet coefficients, in contrast to the many Fourier components that would result from conventional decomposition. We show that the background noise can be dramatically reduced by a thresholding operation in the wavelet domain. The principle is that the background noise codes into many small broadband wavelet coefficients that can be removed without significant degradation of the signal of interest.

NEW THORACIC MURMURS, WITH TWO NEW INSTRUMENTS, THE REFRACTOSCOPE AND THE PARTIAL STETHOSCOPE

PubMed Central

Parker, Frederick D.

1918-01-01

1. An understanding of the physics of sound is essential for a better comprehension of refined auscultation, tone analysis, and the use of these instruments. 2. The detection of variations of the third heart sound should prove a valuable aid in predicting mitral disease. 3. The variations of the outflow sound should prove a valuable aid in determining early aortic lesions with the type of accompanying intimal changes. 4. The character of chamber timbre as distinct from loudness heard as the first and second heart sounds denotes more often the condition of heart muscle, and must not be confounded with valvular disease. 5. The full significance of sound shadows is uncertain. Cardiac sound shadows appear normally in the right axilla and below the left clavicle. Their mode of production is quite clear. 6. Both the third heart sound and the outflow sound may be heard with the ordinary stethoscope. PMID:19868281

Using K-Nearest Neighbor Classification to Diagnose Abnormal Lung Sounds

PubMed Central

Chen, Chin-Hsing; Huang, Wen-Tzeng; Tan, Tan-Hsu; Chang, Cheng-Chun; Chang, Yuan-Jen

2015-01-01

A reported 30% of people worldwide have abnormal lung sounds, including crackles, rhonchi, and wheezes. To date, the traditional stethoscope remains the most popular tool used by physicians to diagnose such abnormal lung sounds, however, many problems arise with the use of a stethoscope, including the effects of environmental noise, the inability to record and store lung sounds for follow-up or tracking, and the physician’s subjective diagnostic experience. This study has developed a digital stethoscope to help physicians overcome these problems when diagnosing abnormal lung sounds. In this digital system, mel-frequency cepstral coefficients (MFCCs) were used to extract the features of lung sounds, and then the K-means algorithm was used for feature clustering, to reduce the amount of data for computation. Finally, the K-nearest neighbor method was used to classify the lung sounds. The proposed system can also be used for home care: if the percentage of abnormal lung sound frames is > 30% of the whole test signal, the system can automatically warn the user to visit a physician for diagnosis. We also used bend sensors together with an amplification circuit, Bluetooth, and a microcontroller to implement a respiration detector. The respiratory signal extracted by the bend sensors can be transmitted to the computer via Bluetooth to calculate the respiratory cycle, for real-time assessment. If an abnormal status is detected, the device will warn the user automatically. Experimental results indicated that the error in respiratory cycles between measured and actual values was only 6.8%, illustrating the potential of our detector for home care applications. PMID:26053756

Development of a tele-stethoscope and its application in pediatric cardiology.

PubMed

Hedayioglu, F L; Mattos, S S; Moser, L; de Lima, M E

2007-01-01

Over the years, many attempts have been made to develop special stethoscopes for the teaching of auscultation. The objective of this article is to report on the experience with the development and implementation of an electronic stethoscope and a virtual library of cardiac sounds. There were four stages to this project: (1) the building of the prototype to acquire, filter and amplify the cardiac sounds, (2) the development of a software program to record, reproduce and visualize them, (3) the testing of the prototype in a clinical scenario, and (4) the development of an internet site, to store and display the sounds collected. The first two stages are now complete. The prototype underwent an initial evaluation in a clinical scenario within the Unit and during virtual out-patient clinical sessions. One hundred auscultations were recorded during these tests. They were reviewed and discussed on-line by a panel of experience cardiologists during the sessions. Although the sounds were considered "satisfactory" for diagnostic purposes by the cardiology team, they identified some qualitative differences in the electronic recorded auscultations, such as a higher pitch of the recorded sounds. Prospective clinical studies are now being conducted to further evaluate the interference of the electronic device in the physicians' capability to diagnose different cardiac conditions. An internet site (www.caduceusvirtual.com.br/ auscultaped) was developed to host these cardiac auscultations. It is set as a library of cardiac sounds, catalogued by pathologies and already contains examples from auscultations of the majority of common congenital heart lesions, such as septal defects and valvar lesions.

Impact of the presence of medical equipment in images on viewers' perceptions of the trustworthiness of an individual on-screen.

PubMed

Jiwa, Moyez; Millett, Stephan; Meng, Xingqiong; Hewitt, Vivien M

2012-07-10

It is now common practice for doctors to consult patients by means other than face-to-face, often appearing before the patient on a computer screen. Also, many websites are using depictions of health professionals to increase the credibility of their services. Being trustworthy is an essential attribute for successful ehealth services. Little is known about which depicted accessories make a health professional appear more trustworthy. To estimate the odds of an individual on-screen being rated trustworthy when viewed in a static image holding or wearing specific items of medical equipment. We surveyed consecutive people attending community pharmacies to collect prescriptions in Western Australia. Respondents were presented with a series of 10 photographs, generated at random, of a man with varying numbers and combinations of medical equipment: stethoscope, reflex hammer, surgical scrubs, otoscope, and pen. They were then invited to rate the man as honest, trustworthy, honorable, moral, ethical, or genuine, or a combination of these, on the Source Credibility Scale. A total of 168 of 250 people gave informed consent, for a participation rate of 67.2%. There were 102 female and 66 male respondents. Of the 168 respondents, 96 (57%) were born in Australia and 102 (60.7%) were attending medical practices with more than one general practitioner. The mean age of respondents was 47 (SD 16) years (range 26-92 years). When only 1 item was present in an image, the stethoscope was associated with the highest odds for the person being considered honest (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.6-4.3), trustworthy (OR 2.3, 95% CI 1.4-3.8), honorable (OR 2.7, 95% CI 1.6-4.5), moral (OR 2.4 95% CI 1.4-4.1), ethical (OR 2.6, 95% CI 1.5-4.6), and genuine (OR 1.8, 95% CI 1.0-3.1). The presence of a stethoscope increased the odds of the person being rated in a positive light in all photographs in which it was included. When an individual is portrayed in a static image, concurrent presentation of 3 or more items of medical equipment, and especially a stethoscope, is likely to exert a positive influence on the viewers' perceptions of the qualities of the person depicted.

Educational Gardening.

ERIC Educational Resources Information Center

Lovejoy, Sharon

1998-01-01

A naturalist and designer of public gardens relates her experiences of introducing children to plants and gardens using equipment such as binoculars, stethoscopes, notebooks, photographs, and magnifying glasses. Article provides information is given about many plants, their uses, and related child-centered activities (such as a namesake pumpkins…

Comparison between Two Endotracheal Tube Cuff Inflation Methods; Just-Seal Vs. Stethoscope-Guided.

PubMed

Borhazowal, Rishiraj; Harde, Minal; Bhadade, Rakesh; Dave, Sona; Aswar, Swapnil Ganeshrao

2017-06-01

The Endotracheal Tube (ETT) cuff performs a critical function of sealing the airway during positive pressure ventilation. There is a narrow range of cuff pressure required to maintain a functionally safe seal without exceeding capillary blood pressure. We aimed to compare Just-Seal (JS) and Stethoscope-Guided (SG) method of ETT cuff inflation with respect to the volume of air required to inflate the cuff, the manometric cuff pressure achieved and also to assess for the occurrence of postoperative sore throat after extubation in both the groups. It was a prospective observational study done in a Tertiary Teaching Public Hospital over a period of 1½ years on 100 patients with 50 each in two groups; JS or SG method of cuff inflation. SPSS Version 17 was used for data analysis. Statistically significant difference (p-value of less than 0.05) was noted between the two methods based on the volume of air injected into the cuff {the mean volume injected in JS was 6.79 ml and in the SG was 4.95 ml with p=5.71E-16 (< 0.05)} and cuff pressure achieved {mean cuff pressure achieved was 38.80 cm H 2 O in the JS and 29.64 cm H 2 O in SG with p=2.29E-14 (< 0.05)}. The incidence of post extubation sore throat was 54% (27 in 50) in the JS group and only 12% (6 in 50) in the SG; p= 0.00000797. ETT cuff inflation guided by a stethoscope is an effective technique for ensuring appropriate cuff pressures thus accomplishing the objective of providing safe and superior quality care of the patient both during and after anaesthesia and reducing the likelihood of even minimal risk complications that may still have legal implications.

Smartphone attachment for stethoscope recording.

PubMed

Thompson, Jeff

2015-01-01

With the ubiquity of smartphones and the rising technology of 3D printing, novel devices can be developed that leverage the "computer in your pocket" and rapid prototyping technologies toward scientific, medical, engineering, and creative purposes. This paper describes such a device: a simple 3D-printed extension for Apple's iPhone that allows the sound from an off-the-shelf acoustic stethoscope to be recorded using the phone's built-in microphone. The attachment's digital 3D files can be easily shared, modified for similar phones and devices capable of recording audio, and in combination with 3D printing technology allow for fabrication of a durable device without need for an entire factory of expensive and specialized machining tools. It is hoped that by releasing this device as an open source set of printable files that can be downloaded and reproduced cheaply, others can make use of these developments where access to cost-prohibitive, specialized medical instruments are not available. Coupled with specialized smartphone software ("apps"), more sophisticated and automated diagnostics may also be possible on-site.

Unvoiced Speech Recognition Using Tissue-Conductive Acoustic Sensor

NASA Astrophysics Data System (ADS)

Heracleous, Panikos; Kaino, Tomomi; Saruwatari, Hiroshi; Shikano, Kiyohiro

2006-12-01

We present the use of stethoscope and silicon NAM (nonaudible murmur) microphones in automatic speech recognition. NAM microphones are special acoustic sensors, which are attached behind the talker's ear and can capture not only normal (audible) speech, but also very quietly uttered speech (nonaudible murmur). As a result, NAM microphones can be applied in automatic speech recognition systems when privacy is desired in human-machine communication. Moreover, NAM microphones show robustness against noise and they might be used in special systems (speech recognition, speech transform, etc.) for sound-impaired people. Using adaptation techniques and a small amount of training data, we achieved for a 20 k dictation task a[InlineEquation not available: see fulltext.] word accuracy for nonaudible murmur recognition in a clean environment. In this paper, we also investigate nonaudible murmur recognition in noisy environments and the effect of the Lombard reflex on nonaudible murmur recognition. We also propose three methods to integrate audible speech and nonaudible murmur recognition using a stethoscope NAM microphone with very promising results.

Endotracheal tube leak pressure and tracheal lumen size in swine.

PubMed

Finholt, D A; Audenaert, S M; Stirt, J A; Marcella, K L; Frierson, H F; Suddarth, L T; Raphaely, R C

1986-06-01

Endotracheal tube "leak" is often estimated in children to judge the fit of uncuffed endotracheal tubes within the trachea. Twenty-five swine were intubated with uncuffed tracheal tubes to determine whether a more sensitive measurement of leaks could be devised and whether leak pressure estimates fit between tracheal tube and trachea. We compared leak pressure measurement using a stethoscope and aneroid manometer with a technique using a microphone, pressure transducer, and recorder, and found no differences between the two methods. The tracheas were then removed and slides prepared of tracheal cross-sectional specimens. Regression analysis revealed a linear relationship between tracheal lumen size and tracheal tube size for both low leak pressure (y = -0.4 + 0.79x, r = 0.88, P less than 0.05) and high leak pressure (y = -2.9 + 0.71x, r = 0.92, P less than 0.05) groups. We conclude that leak testing with a stethoscope and aneroid manometer is sensitive and accurate, and that tracheal tube leak pressure accurately portrays fit between tube and trachea.

The Salmonella Mutagenicity Assay: The Stethoscope of Genetic Toxicology for the 21 st Century

EPA Science Inventory

OBJECTIVES: According to the 2007 National Research Council report Toxicology for the Twenty-first Century, modem methods ("omics," in vitro assays, high-throughput testing, computational methods, etc.) will lead to the emergence of a new approach to toxicology. The Salmonella ma...

Detection of boundary-layer transitions in wind tunnels

NASA Technical Reports Server (NTRS)

Wood, W. R.; Somers, D. M.

1978-01-01

Accelerometer replaces stethoscope in technique for detection of laminar-to-turbulent boundary-layer transitions on wind-tunnel models. Technique allows measurements above or below atmospheric pressure because human operator is not required within tunnel. Data may be taken from accelerometer, and pressure transducer simultaneously, and delivered to systems for analysis.

A Managed Care Model for the Military Departments

DTIC Science & Technology

1990-05-15

Seattle reports that a widely used technique for electronic monitoring of a fetal heart during delivery is "no more effective than a stethoscope in 6...detecting fetal distress."𔃿 The study director went on to say that obstetricians will probably continue to use the technique to avoid possible

Survey of Physical Assessment Course Offerings in American Colleges of Pharmacy.

ERIC Educational Resources Information Center

da Camara, Carlos C.; And Others

1996-01-01

A survey of 55 pharmacy schools found that of those offering a pharmacy doctoral program, three-fourths had a separate course devoted to physical assessment of patients, most offered in the third professional year. Most require students to demonstrate use of stethoscope, sphygmomanometer, ophthalmo-otoscope, tuning fork, reflex hammer. Reasons for…

Phonocardiography with a smartphone

NASA Astrophysics Data System (ADS)

Thoms, Lars-Jochen; Colicchia, Giuseppe; Girwidz, Raimund

2017-03-01

When a stethoscope is placed on the chest over the heart, sounds coming from the heart can be directly heard. These sound vibrations can be captured through a microphone and the electrical signals from the transducer can be processed and plotted in a phonocardiogram. Students can easily use a microphone and smartphone to capture and analyse characteristic heart sounds.

Portable system for auscultation and lung sound analysis.

PubMed

Nabiev, Rustam; Glazova, Anna; Olyinik, Valery; Makarenkova, Anastasiia; Makarenkov, Anatolii; Rakhimov, Abdulvosid; Felländer-Tsai, Li

2014-01-01

A portable system for auscultation and lung sound analysis has been developed, including the original electronic stethoscope coupled with mobile devices and special algorithms for the automated analysis of pulmonary sound signals. It's planned that the developed system will be used for monitoring of health status of patients with various pulmonary diseases.

Phonocardiography with a Smartphone

ERIC Educational Resources Information Center

Thoms, Lars-Jochen; Colicchia, Giuseppe; Girwidz, Raimund

2017-01-01

When a stethoscope is placed on the chest over the heart, sounds coming from the heart can be directly heard. These sound vibrations can be captured through a microphone and the electrical signals from the transducer can be processed and plotted in a phonocardiogram. Students can easily use a microphone and smartphone to capture and analyse…

Technology for enhancing chest auscultation in clinical simulation.

PubMed

Ward, Jeffrey J; Wattier, Bryan A

2011-06-01

The ability to use an acoustic stethoscope to detect lung and/or heart sounds, and then to then communicate one's interpretation of those sounds is an essential skill for many medical professionals. Interpretation of lung and heart sounds, in the context of history and other examination findings, often aids the differential diagnosis. Bedside assessment of changing auscultation findings may also guide treatment. Learning lung and heart auscultation skills typically involves listening to pre-recorded normal and adventitious sounds, often followed by laboratory instruction to guide stethoscope placement, and finally correlating the sounds with the associated pathophysiology and pathology. Recently, medical simulation has become an important tool for teaching prior to clinical practice, and for evaluating bedside auscultation skills. When simulating cardiovascular or pulmonary problems, high-quality lung and heart sounds should be able to accurately corroborate other findings such as vital signs, arterial blood gas values, or imaging. Digital audio technology, the Internet, and high-fidelity simulators have increased opportunities for educators and learners. We review the application of these technologies and describe options for reproducing lung and heart sounds, as well as their advantages and potential limitations.

Assessment of children for acute respiratory infections in hospital outpatients in Tanzania: what drives good practice?

PubMed

Chandler, Clare I R; Nadjm, Behzad; Boniface, Gloria; Juma, Kaseem; Reyburn, Hugh; Whitty, Christopher J M

2008-12-01

Respiratory infections cause significant mortality in developing countries but are frequently undiagnosed. Reasons for this are unclear. We observed 1,081 outpatient consultations with patients less than five years of age in Tanzania. In 554 patients with cough or difficulty breathing, the absolute percentages examined were 5% for respiratory rate counted, 14% chest exposed, and 25% stethoscope used. Decisions to conduct particular examinations did appear to follow clinical logic, with odds ratios of 4.28 for counting respiratory rate (95% confidence interval [CI]=1.75-10.47), 2.57 for exposing the chest (95% CI=1.67-3.95), and 18.91 for using a stethoscope (95% CI=9.52-37.57) in patients with cough or difficulty breathing. Non-clinical variables, including salary level, were also associated with examinations, and history taking was more common among clinicians originating outside the hospital area. Although respiratory examinations are relatively more common in those with cough or difficulty breathing, the absolute rates are low and related to non-clinical and clinical factors.

A simplified form of cardiotocography for antenatal fetal assessment.

PubMed

Mahomed, K; Gupta, B K; Matikiti, L; Murape, T S

1992-12-01

Antenatal cardiotocography has become the primary method of evaluation of fetal wellbeing, and the relationship between the presence of fetal heart rate accelerations in response to fetal movement and subsequent good fetal outcome has been demonstrated. However, in areas where electronic monitors are few or not available it would be useful if such accelerations could be demonstrated using the Pinard stethoscope. A prospective study involving 200 women with a singleton pregnancy of more than 34 weeks gestation was performed at Harare Maternity Hospital, Harare, Zimbabwe, when a 6 min electronic trace using an external transducer was compared with simultaneously performed 6 min manual record using the Pinard stethoscope. The findings showed that the manual record has a sensitivity of 75% and although traces with excessive base line variability would show an acceleration on the manual record, in no case with a flat trace was an acceleration noted on the manual record. This acceptable degree of sensitivity would allow for a significant decrease in the number of women being referred for electronic tracing and would be a more appropriate use of limited resources in terms of manpower and equipment.

Music-of-Light Stethoscope: A Demonstration of the Photoacoustic Effect

ERIC Educational Resources Information Center

Nikitichev, D. I.; Xia, W.; Hill, E.; Mosse, C. A.; Perkins, T.; Konyn, K.; Ourselin, S.; Desjardins, A. E.; Vercauteren, T.

2016-01-01

In this paper we present a system aimed at demonstrating the photoacoustic (PA) effect for educational purposes. PA imaging is a hybrid imaging modality that requires no contrast agent and has a great potential for spine and brain lesion characterisation, breast cancer and blood flow monitoring notably in the context of fetal surgery. It relies on…

Students Combine Studies with Stethoscopes | Poster

Cancer.gov

By Nancy Parrish, Staff Writer Janine Bahsali and Esther Shafer are Middletown High School seniors who go to school in the morning and spend their afternoons taking blood pressure, assisting with physical exams, learning how to draw a blood sample and stitch a wound closed, and generally assisting the staff of Occupational Health Services (OHS), a health care department

Reframing the Field of Gender and Nursing Education

ERIC Educational Resources Information Center

Solbraekke, Kari Nyheim; Solvoll, Betty-Ann; Heggen, Kristin M.

2013-01-01

The aim of this article is to explore how male students learn to practice nursing and the role of technology in their training process. The study is inspired by Bruno Latour's understanding of social interaction as an interplay between humans and technology. The students' use of the washcloth and the stethoscope, two significant nursing tools, is…

"How Am I Doing?": Many Problems but Few Solutions Related to Feedback Delivery in Undergraduate Psychiatry Education

ERIC Educational Resources Information Center

McIlwrick, Joann; Nair, Bina; Montgomery, Gregory

2006-01-01

Objective: Giving performance feedback to students in psychiatry requires particular delicacy and skill since a critique of the subjective artistry of the psychiatric interview may be felt more personally than a critique of an objective skill, such as eliciting a reflex or applying a stethoscope to the chest. Thus, one would expect that…

Telemedicine. Final report/project accomplishments summary CRADA number 95-KCP-1014

DOE Office of Scientific and Technical Information (OSTI.GOV)

VanDeusen, A.L.

1997-04-01

This project was initiated to fill existing voids in the telemedicine equipment market. Currently, when a medical facility adds telemedicine capability to their video conference system, they must purchase expensive and bulky encoders and decoders in order to send information over the available data channel. Even with this expensive equipment, only one data type (stethoscope or ECG) can be sent at a time. In addition, since existing encoders and decoders are not designed specifically for telemedicine, special cables must be built to connect with this equipment. This project resulted in the design and construction of an encoder/decoder system that resolvedmore » these issues. The unit (referred to as the Telecoder) is designed specifically for the telemedicine market. The Telecoder is compact, handles two types of data (stethoscope and ECG) simultaneously, integrates with existing medical equipment, and is less expensive. In addition to the Telecoder module, a prototype was built that adds all the necessary logic and interfaces necessary to integrate the basic encoder design into additional Cardionics products. Although a complete integration into other Cardionics products was not in the scope of this CRADA, all the basic design work has been done to allow Cardionics to complete the work.« less

Students Combine Studies with Stethoscopes | Poster

Cancer.gov

By Nancy Parrish, Staff Writer Janine Bahsali and Esther Shafer are Middletown High School seniors who go to school in the morning and spend their afternoons taking blood pressure, assisting with physical exams, learning how to draw a blood sample and stitch a wound closed, and generally assisting the staff of Occupational Health Services (OHS), a health care department serving more than 2,000 employees at NCI at Frederick.

US Army Institute of Surgical Research Annual Research Progress Report for Fiscal Year 1987.

DTIC Science & Technology

1987-10-01

oases, respiratory rate, chest roentgenograms), cardiovascular (blood pressure, central venous pressure, cardiac output), and renal (urine output, urine...Monitoring includes the precordial and/or esophageal stethoscope, peripheral pulse, blood pressure, central venous pressure, Swan-Ganz catheter... central venous , peripheral venous , and Swan-Ganz (7F, American Edward Laboratories, Irvine CA) catheters and an esophageal balloon were inserted. After a 2

About egophony.

PubMed

Sapira, J D

1995-09-01

Egophony is a change in timbre (Ee to A) but not pitch or volume. It is due to a decrease in the amplitude and an increase in the frequency [corrected] of the second formant, produced by solid (including compressed lung) interposed between the resonator and the stethoscope head. This explains certain difficulties in learning this valuable but currently neglected sign as well as in understanding certain physiologic false-positive occurrences.

Wavelet-Based Adaptive Denoising of Phonocardiographic Records

DTIC Science & Technology

2001-10-25

phonocardiography, including the recording of fetal heart sounds on the maternal abdominal surface. Keywords - phonocardiography, wavelets, denoising, signal... fetal heart rate monitoring [2], [7], [8]. Unfortunately, heart sound records are very often disturbed by various factors, which can prohibit their...recorded the acoustic signals. The first microphone was inserted into the focus of a stethoscope and it recorded the acoustic signals of the heart ( heart

Instructional Methods for Neuroscience in Nurse Anesthesia Graduate Programs: A Survey of Educational Programs

DTIC Science & Technology

1999-10-01

Sciences A. Anatomy, physiology and pathophysiology 1. Cardiovascular a. Arrhythmias b. Ischemic heart disease/angina c. Myocardial infarction d...Hypertension e. Congestive Heart Failure f. Shock Instructional Methods 66 g. Valvular Heart disease h. Cardiomyopathy i. Peripheral vascular disease j...Pulmonary artery pressure monitoring Instructional Methods 71 3. Precordial/esophageal stethoscope /Doppler 4. Respiratory monitoring a. Apnea monitor b

An open real-time tele-stethoscopy system.

PubMed

Foche-Perez, Ignacio; Ramirez-Payba, Rodolfo; Hirigoyen-Emparanza, German; Balducci-Gonzalez, Fernando; Simo-Reigadas, Francisco-Javier; Seoane-Pascual, Joaquin; Corral-Peñafiel, Jaime; Martinez-Fernandez, Andres

2012-08-23

Acute respiratory infections are the leading cause of childhood mortality. The lack of physicians in rural areas of developing countries makes difficult their correct diagnosis and treatment. The staff of rural health facilities (health-care technicians) may not be qualified to distinguish respiratory diseases by auscultation. For this reason, the goal of this project is the development of a tele-stethoscopy system that allows a physician to receive real-time cardio-respiratory sounds from a remote auscultation, as well as video images showing where the technician is placing the stethoscope on the patient's body. A real-time wireless stethoscopy system was designed. The initial requirements were: 1) The system must send audio and video synchronously over IP networks, not requiring an Internet connection; 2) It must preserve the quality of cardiorespiratory sounds, allowing to adapt the binaural pieces and the chestpiece of standard stethoscopes, and; 3) Cardiorespiratory sounds should be recordable at both sides of the communication. In order to verify the diagnostic capacity of the system, a clinical validation with eight specialists has been designed. In a preliminary test, twelve patients have been auscultated by all the physicians using the tele-stethoscopy system, versus a local auscultation using traditional stethoscope. The system must allow listen the cardiac (systolic and diastolic murmurs, gallop sound, arrhythmias) and respiratory (rhonchi, rales and crepitations, wheeze, diminished and bronchial breath sounds, pleural friction rub) sounds. The design, development and initial validation of the real-time wireless tele-stethoscopy system are described in detail. The system was conceived from scratch as open-source, low-cost and designed in such a way that many universities and small local companies in developing countries may manufacture it. Only free open-source software has been used in order to minimize manufacturing costs and look for alliances to support its improvement and adaptation. The microcontroller firmware code, the computer software code and the PCB schematics are available for free download in a subversion repository hosted in SourceForge. It has been shown that real-time tele-stethoscopy, together with a videoconference system that allows a remote specialist to oversee the auscultation, may be a very helpful tool in rural areas of developing countries.

An Evaluation of the Ability of Navy Hospital Corpsmen to Collect Chest Pain Data from Patients

DTIC Science & Technology

1984-01-11

PREVIOUS CARDIO-RESPIRATOFJY ILLNESS: (significant illenss either cardiovascular or respiratory ) YES (64) NO (65) PREVIOUS MAJOR SURGERY...clavicle to chin - elevated) otherwise circle normal) NORMAL (97) RAISED (98) RESPIRATORY MOVEMENT: (abnormal = the difference between...ABNORMAL (100) HEART SOUNDS: (with a stethoscope listen to the 1st and 2nd heart sounds; normal - lub-dub, lub-dub; abnormal " everything else

The Accutension Stetho, an automated auscultatory device to validate automated sphygmomanometer readings in individual patients.

PubMed

Alpert, Bruce S

2018-04-06

The aim of this report is to describe a new device that can validate, by automated auscultation, individual blood pressure (BP) readings taken by automated sphygmomanometers.The Accutension Stetho utilizes a smartphone application in conjunction with a specially designed stethoscope that interfaces directly into the smartphone via the earphone jack. The Korotkoff sounds are recorded by the application and are analyzed by the operator on the screen of the smartphone simultaneously with the images from the sphygmomanometer screen during BP estimation. Current auscultatory validation standards require at least 85 subjects and strict statistical criteria for passage. A device that passes can make no guarantee of accuracy on individual patients. The Accutension Stetho is an inexpensive smartphone/stethoscope kit combination that estimates precise BP values by auscultation to confirm the accuracy of an automated sphygmomanometer's readings on individual patients. This should be of great value for both professional and, in certain circumstances, self-measurement BP. Patients will avoid both unnecessary treatment and errors of underestimation of BP, in which the patient requires therapy. The Stetho's software has been validated in an independent ANSI/AAMI/ISO standard study. The Stetho has been shown to perform without difficulty in multiple deflation-based devices by many manufacturers.

Bedside ultrasonography (US), Echoscopy and US point of care as a new kind of stethoscope for Internal Medicine Departments: the training program of the Italian Internal Medicine Society (SIMI).

PubMed

Arienti, Vincenzo; Di Giulio, Rosella; Cogliati, Chiara; Accogli, Esterita; Aluigi, Leonardo; Corazza, Gino Roberto

2014-10-01

In recent years, thanks to the development of miniaturized ultrasound devices, comparable to personal computers, tablets and even to smart phones, we have seen an increasing use of bedside ultrasound in internal medicine departments as a novel kind of ultrasound stethoscope. The clinical ultrasound-assisted approach has proved to be particularly useful in assessing patients with nodules of the neck, dyspnoea, abdominal pain, and with limb edema. In several cases, it has allowed a simple, rapid and precise diagnosis. Since 2005, the Italian Society of Internal Medicine and its Ultrasound Study Group has been holding a Summer School and training courses in ultrasound for residents in internal medicine. A national network of schools in bedside ultrasound was then organized for internal medicine specialists who want to learn this technique. Because bedside ultrasound is a user-dependent diagnostic method, it is important to define the limits and advantages of different new ultrasound devices, to classify them (i.e. Echoscopy and Point of Care Ultrasound), to establish appropriate different levels of competence and to ensure their specific training. In this review, we describe the point of view of the Italian Internal Medicine Society on these topics.

The Generation and Propagation of Arterial Murmurs from a Stenosed Artery: A Computational Study

NASA Astrophysics Data System (ADS)

Zhu, Chi; Seo, Jung-Hee; Bakhshaee, Hani; Mittal, Rajat

2015-11-01

Cardiac auscultation - the procedure of diagnosing cardiovascular conditions using the stethoscope - has been used effectively for over a hundred years but still, the flow mechanism(s) responsible for the generation of these murmurs, as well as the effect of intervening tissue on the propagation of these murmurs, is not well understood. In this study, a one-way coupled, hybrid approach is used to investigate the propagation of murmurs generated from the flow in a stenosed artery. Specifically, the flow in the modeled artery is solved by an incompressible Navier-Stokes solver with the immersed-boundary method. The structural wave propagation in the tissue is resolved by a high-order, linear viscoelastic wave solver, and a mathematical decomposition is applied to separate the compressional and shear component of the acoustic wave propagating through the tissue. The simulations suggest, somewhat counterintuitively, that the shear wave contributes a significant component to the signal picked up by a stethoscope, and that this component carries much of the information that characterizes the source of the murmur. The implications of this for cardiac auscultation and further modeling of hemoacoustics are discussed. The effect of the stenosis severity and the flow pulsatility will also be investigated. The authors would like to acknowledge the SCH for funding this project.

Hand Washing Practices Among Emergency Medical Services Providers.

PubMed

Bucher, Joshua; Donovan, Colleen; Ohman-Strickland, Pamela; McCoy, Jonathan

2015-09-01

Hand hygiene is an important component of infection control efforts. Our primary and secondary goals were to determine the reported rates of hand washing and stethoscope cleaning in emergency medical services (EMS) workers, respectively. We designed a survey about hand hygiene practices. The survey was distributed to various national EMS organizations through e-mail. Descriptive statistics were calculated for survey items (responses on a Likert scale) and subpopulations of survey respondents to identify relationships between variables. We used analysis of variance to test differences in means between the subgroups. There were 1,494 responses. Overall, reported hand hygiene practices were poor among pre-hospital providers in all clinical situations. Women reported that they washed their hands more frequently than men overall, although the differences were unlikely to be clinically significant. Hygiene after invasive procedures was reported to be poor. The presence of available hand sanitizer in the ambulance did not improve reported hygiene rates but improved reported rates of cleaning the stethoscope (absolute difference 0.4, p=0.0003). Providers who brought their own sanitizer were more likely to clean their hands. Reported hand hygiene is poor amongst pre-hospital providers. There is a need for future intervention to improve reported performance in pre-hospital provider hand washing.

The prevalence and character of crackles (rales) in young women without significant lung disease.

PubMed

Workum, P; Holford, S K; Delbono, E A; Murphy, R L

1982-11-01

Although some investigators have reported that crackles are present only in persons with lung disease, others say they also occur in normal persons. In order to clarify this difference of opinion, we determined the prevalence of crackles in 56 women without significant lung disease. The subjects ranged from 19 to 33 yr of age (mean, 21.3). They all had a FVC greater than 80% predicted and a FEV1/FVC ratio greater than 75%. None had a history of acute or chronic lung disease. During slow inspirations from residual volume, midinspiratory fine crackles were heard at the anterior bases in 35 of 56 subjects by a physician using an acoustic stethoscope, whereas a bioengineer using an 800 Hertz high pass filtered stethoscope heard crackles in 53 subjects. Crackles during tidal breathing were heard in 2 subjects. It is postulated that the crackles noted after expiration to residual volume are nonpathologic, and occur when basilar airways, which close at the end of a forced expiration, suddenly open during inspiration. Examination of the quality, timing, and anatomic distribution of the crackles in apparently normal subjects suggests that they can often be distinguished from those resulting from diseases such as bronchitis, interstitial fibrosis, and congestive heart failure.

Lung and Heart Sounds Analysis: State-of-the-Art and Future Trends.

PubMed

Padilla-Ortiz, Ana L; Ibarra, David

2018-01-01

Lung sounds, which include all sounds that are produced during the mechanism of respiration, may be classified into normal breath sounds and adventitious sounds. Normal breath sounds occur when no respiratory problems exist, whereas adventitious lung sounds (wheeze, rhonchi, crackle, etc.) are usually associated with certain pulmonary pathologies. Heart and lung sounds that are heard using a stethoscope are the result of mechanical interactions that indicate operation of cardiac and respiratory systems, respectively. In this article, we review the research conducted during the last six years on lung and heart sounds, instrumentation and data sources (sensors and databases), technological advances, and perspectives in processing and data analysis. Our review suggests that chronic obstructive pulmonary disease (COPD) and asthma are the most common respiratory diseases reported on in the literature; related diseases that are less analyzed include chronic bronchitis, idiopathic pulmonary fibrosis, congestive heart failure, and parenchymal pathology. Some new findings regarding the methodologies associated with advances in the electronic stethoscope have been presented for the auscultatory heart sound signaling process, including analysis and clarification of resulting sounds to create a diagnosis based on a quantifiable medical assessment. The availability of automatic interpretation of high precision of heart and lung sounds opens interesting possibilities for cardiovascular diagnosis as well as potential for intelligent diagnosis of heart and lung diseases.

[Respiratory sounds].

PubMed

Marquet, P

1995-01-01

After having invented the stethoscope, Laennec published his treatise on auscultation in 1819, describing the acoustic events generated by ventilation and linking them with anatomopathological findings. The weak points of his semiology lay in its subjective and interpretative character, expressed by an imprecise and picturesque nomenclature. Technical studies of breath sounds began in the middle of the twentieth century, and this enabled the American Thoracic Society to elaborate a new classification of adventitious noises based on a few physical characteristics. This terminology replaced that of Laennec or his translators (except in France). The waveforms of the different normal and adventitious noises have been well described. However, only the study of the time evolution of their tone (frequency-amplitude-time relationship) will enable a complete analysis of these phenomena. This approach has been undertaken by a few teams but much remains to be done, in particular in relation to discontinuous noises (crackles). Technology development raises hope for the design, in near future, of automatic processes for respiratory noise detection and classification. Systematic research into the production mechanisms and sites of these noises has progressed equally. It should, in time, reinforce their semiological value and give to auscultation, either instrumental or using the stethoscope or instrumentally, an increased diagnostic power and the status of respiratory function test.

Hand Washing Practices Among Emergency Medical Services Providers

PubMed Central

Bucher, Joshua; Donovan, Colleen; Ohman-Strickland, Pamela; McCoy, Jonathan

2015-01-01

Introduction Hand hygiene is an important component of infection control efforts. Our primary and secondary goals were to determine the reported rates of hand washing and stethoscope cleaning in emergency medical services (EMS) workers, respectively. Methods We designed a survey about hand hygiene practices. The survey was distributed to various national EMS organizations through e-mail. Descriptive statistics were calculated for survey items (responses on a Likert scale) and subpopulations of survey respondents to identify relationships between variables. We used analysis of variance to test differences in means between the subgroups. Results There were 1,494 responses. Overall, reported hand hygiene practices were poor among pre-hospital providers in all clinical situations. Women reported that they washed their hands more frequently than men overall, although the differences were unlikely to be clinically significant. Hygiene after invasive procedures was reported to be poor. The presence of available hand sanitizer in the ambulance did not improve reported hygiene rates but improved reported rates of cleaning the stethoscope (absolute difference 0.4, p=0.0003). Providers who brought their own sanitizer were more likely to clean their hands. Conclusion Reported hand hygiene is poor amongst pre-hospital providers. There is a need for future intervention to improve reported performance in pre-hospital provider hand washing. PMID:26587098

An open real-time tele-stethoscopy system

PubMed Central

2012-01-01

Background Acute respiratory infections are the leading cause of childhood mortality. The lack of physicians in rural areas of developing countries makes difficult their correct diagnosis and treatment. The staff of rural health facilities (health-care technicians) may not be qualified to distinguish respiratory diseases by auscultation. For this reason, the goal of this project is the development of a tele-stethoscopy system that allows a physician to receive real-time cardio-respiratory sounds from a remote auscultation, as well as video images showing where the technician is placing the stethoscope on the patient’s body. Methods A real-time wireless stethoscopy system was designed. The initial requirements were: 1) The system must send audio and video synchronously over IP networks, not requiring an Internet connection; 2) It must preserve the quality of cardiorespiratory sounds, allowing to adapt the binaural pieces and the chestpiece of standard stethoscopes, and; 3) Cardiorespiratory sounds should be recordable at both sides of the communication. In order to verify the diagnostic capacity of the system, a clinical validation with eight specialists has been designed. In a preliminary test, twelve patients have been auscultated by all the physicians using the tele-stethoscopy system, versus a local auscultation using traditional stethoscope. The system must allow listen the cardiac (systolic and diastolic murmurs, gallop sound, arrhythmias) and respiratory (rhonchi, rales and crepitations, wheeze, diminished and bronchial breath sounds, pleural friction rub) sounds. Results The design, development and initial validation of the real-time wireless tele-stethoscopy system are described in detail. The system was conceived from scratch as open-source, low-cost and designed in such a way that many universities and small local companies in developing countries may manufacture it. Only free open-source software has been used in order to minimize manufacturing costs and look for alliances to support its improvement and adaptation. The microcontroller firmware code, the computer software code and the PCB schematics are available for free download in a subversion repository hosted in SourceForge. Conclusions It has been shown that real-time tele-stethoscopy, together with a videoconference system that allows a remote specialist to oversee the auscultation, may be a very helpful tool in rural areas of developing countries. PMID:22917062

Astronaut Paul Weitz gets physical examination from Astronaut Joseph Kerwin

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Paul J. Weitz, Skylab 2 pilot, gets a physical examination by a fellow crewman during the 28-day Skylab 2 mission. Scientist-Astronaut Joseph P. Kerwin, Skylab 2 science pilot and a doctor of medicine, uses a stethoscope to check the Weitz's heartbeat. They are in the Orbital Workshop crew quarters of the Skylab 1 and 2 space station in Earth orbit. This photograph was taken by Charles Conrad Jr., Skylab 2 commander.

Emergency Preparedness Plan. DeWitt Army Community Hospital, Fort Belvoir, Virginia,

DTIC Science & Technology

1997-12-31

demand, dispatch at least one Respiratory Specialist (91V) to the ER rn Department of Familv Practice or senior representative will: (1) /Wnni™ and...be prepared for are: a. Two (2) messengers/runners to the EOC and Triage area(s). b. One or more Respiratory Specialist (91V) to the ER. c. A...Depressors 1 bx Shave Prep Set 50 ea Skin Closure, Adhesive 2 bx Stethoscope 5 ea Dental Mirrors 2 ea Nasal Speculum 2 ea Betadine Surgi-prep Sponge

An Intelligent Pattern Recognition System Based on Neural Network and Wavelet Decomposition for Interpretation of Heart Sounds

DTIC Science & Technology

2001-10-25

wavelet decomposition of signals and classification using neural network. Inputs to the system are the heart sound signals acquired by a stethoscope in a...Proceedings. pp. 415–418, 1990. [3] G. Ergun, “An intelligent diagnostic system for interpretation of arterpartum fetal heart rate tracings based on ANNs and...AN INTELLIGENT PATTERN RECOGNITION SYSTEM BASED ON NEURAL NETWORK AND WAVELET DECOMPOSITION FOR INTERPRETATION OF HEART SOUNDS I. TURKOGLU1, A

Living in a ``stethoscope'': burrow-acoustics promote auditory specializations in subterranean rodents

NASA Astrophysics Data System (ADS)

Lange, Simone; Burda, Hynek; Wegner, Regina E.; Dammann, Philip; Begall, Sabine; Kawalika, Mathias

2007-02-01

Subterranean mammals rely to a great extent on audition for communication and to be alerted to danger. The only hitherto published report on burrow acoustics revealed that in tunnels of blind mole-rats ( Spalax ehrenbergi), airborne sounds of 440 Hz propagated best whereas lower and higher frequencies were effectively attenuated. Morpho-functional analyses classify the ear of subterranean mammals as a low-sensitivity and low-frequency device. Concordantly, hearing is characterized by low sensitivity and a restricted frequency range tuned to low frequencies (0.5-4 kHz). Some authors considered the restricted hearing in subterranean mammals vestigial and degenerate due to under-stimulation. In contrast to this view stand a rich (mostly low-frequency) vocal repertoire and progressive structural specializations of the middle and inner ear. Thus, other authors considered these hearing characteristics adaptive. To test the hypothesis that acoustical environment in burrows of different species of subterranean mammals is similar, we measured sound attenuation in burrows of Fukomys mole-rats (formerly known as Cryptomys, cf. Kock et al. 2006) of two differently sized species at different locations in Zambia. We show that in these burrows, low-frequency sounds (200-800 Hz) are not only least attenuated but also their amplitude may be amplified like in a stethoscope (up to two times over 1 m). We suggest that hearing sensitivity has decreased during evolution of subterranean mammals to avoid over-stimulation of the ear in their natural environment.

Early detection and control of an Acinetobacter baumannii multi-resistant outbreak in a hospital in Quito, Ecuador.

PubMed

Cartelle Gestal, Monica; Zurita, Jeannete; Gualpa, Gabriela; Gonzalez, Cecibel; Paz Y Mino, Ariane

2016-12-30

Acinetobacter baumannii (ABA) is an important opportunistic pathogen associated with high mortality rates in intensive care units (ICUs). An outbreak in the ICU of a secondary-level hospital in Quito, Ecuador, occurred during April and May 2015 and was successfully controlled. Enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) and repetitive element palindromic (REP)-PCR was conducted on all isolates recovered from patients, as well as environmental samples, to confirm the presence of an outbreak. A case-control study was conducted by comparing the clinical histories of the affected patients and of control patients present in the ICU during the outbreak period who did not present a positive culture for ABA. Five patients were infected and two were colonized with the same clonal strain of ABA, which was also identified on the stethoscope and a monitor associated with an isolation room. Statistical analysis of case histories did not identify any additional risk factors, but the outbreak was initiated by one patient in the isolation room of the ICU who was infected with the outbreak strain. All patients who ocupied that room after the index case tested positive for at least one culture of ABA. The outbreak strain was found on the stethoscope, and a subclone was found on the monitor of that room. Having access to basic equipment will enable well-trained professionals to rapidly detect and initiate the control process of an outbreak, saving lives and money spent on nosocomial infection treatments.

Cardio-Pulmonary Stethoscope: Clinical Validation With Heart Failure and Hemodialysis Patients.

PubMed

Iskander, Magdy F; Seto, Todd B; Perron, Ruthsenne Rg; Lim, Eunjung; Qazi, Farhan

2018-05-01

The purpose of this study is to evaluate the accuracy of a noninvasive radiofrequency-based device, the Cardio-Pulmonary Stethoscope (CPS), to monitor heart and respiration rates, and detect changes in lung water content in human experiments and clinical trials. Three human populations (healthy subjects ( ), heart failure (), and hemodialysis () patients) were enrolled in this study. The study was conducted at the University of Hawaii and the Queen's Medical Center in Honolulu, HI, USA. Measurement of heart and respiration rates for all patients was compared with standard FDA - approved monitoring methods. For lung water measurements, CPS data were compared with simultaneous pulmonary capillary wedge pressure (PCWP) measurements for heart failure patients, and with change in weight of extracted fluid for hemodialysis patients. Statistical correlation methods (Pearson, mixed, and intraclass) were used to compare the data and examine accuracy of CPS results. Results show that heart and respiration rates of all patients have excellent correlation factors, r≥0.9. Comparisons with fluid removed during hemodialysis treatment showed correlation factor of to 1, while PCWP measurements of heart failure patients had correlation factor of to 0.97. These results suggest that CPS technology accurately quantifies heart and respiration rates and measure fluid changes in the lungs. The CPS has the potential to accurately monitor lung fluid status noninvasively and continuously in a clinical and outpatient setting. Early and efficient management of lung fluid status is key in managing chronic conditions such heart failure, pulmonary hypertension, and acute respiration distress syndrome.

Spectral analysis of bowel sounds in intestinal obstruction using an electronic stethoscope.

PubMed

Ching, Siok Siong; Tan, Yih Kai

2012-09-07

To determine the value of bowel sounds analysis using an electronic stethoscope to support a clinical diagnosis of intestinal obstruction. Subjects were patients who presented with a diagnosis of possible intestinal obstruction based on symptoms, signs, and radiological findings. A 3M™ Littmann(®) Model 4100 electronic stethoscope was used in this study. With the patients lying supine, six 8-second recordings of bowel sounds were taken from each patient from the lower abdomen. The recordings were analysed for sound duration, sound-to-sound interval, dominant frequency, and peak frequency. Clinical and radiological data were reviewed and the patients were classified as having either acute, subacute, or no bowel obstruction. Comparison of bowel sound characteristics was made between these subgroups of patients. In the presence of an obstruction, the site of obstruction was identified and bowel calibre was also measured to correlate with bowel sounds. A total of 71 patients were studied during the period July 2009 to January 2011. Forty patients had acute bowel obstruction (27 small bowel obstruction and 13 large bowel obstruction), 11 had subacute bowel obstruction (eight in the small bowel and three in large bowel) and 20 had no bowel obstruction (diagnoses of other conditions were made). Twenty-five patients received surgical intervention (35.2%) during the same admission for acute abdominal conditions. A total of 426 recordings were made and 420 recordings were used for analysis. There was no significant difference in sound-to-sound interval, dominant frequency, and peak frequency among patients with acute bowel obstruction, subacute bowel obstruction, and no bowel obstruction. In acute large bowel obstruction, the sound duration was significantly longer (median 0.81 s vs 0.55 s, P = 0.021) and the dominant frequency was significantly higher (median 440 Hz vs 288 Hz, P = 0.003) when compared to acute small bowel obstruction. No significant difference was seen between acute large bowel obstruction and large bowel pseudo-obstruction. For patients with small bowel obstruction, the sound-to-sound interval was significantly longer in those who subsequently underwent surgery compared with those treated non-operatively (median 1.29 s vs 0.63 s, P < 0.001). There was no correlation between bowel calibre and bowel sound characteristics in both acute small bowel obstruction and acute large bowel obstruction. Auscultation of bowel sounds is non-specific for diagnosing bowel obstruction. Differences in sound characteristics between large bowel and small bowel obstruction may help determine the likely site of obstruction.

Spectral analysis of bowel sounds in intestinal obstruction using an electronic stethoscope

PubMed Central

Ching, Siok Siong; Tan, Yih Kai

2012-01-01

AIM: To determine the value of bowel sounds analysis using an electronic stethoscope to support a clinical diagnosis of intestinal obstruction. METHODS: Subjects were patients who presented with a diagnosis of possible intestinal obstruction based on symptoms, signs, and radiological findings. A 3M™ Littmann® Model 4100 electronic stethoscope was used in this study. With the patients lying supine, six 8-second recordings of bowel sounds were taken from each patient from the lower abdomen. The recordings were analysed for sound duration, sound-to-sound interval, dominant frequency, and peak frequency. Clinical and radiological data were reviewed and the patients were classified as having either acute, subacute, or no bowel obstruction. Comparison of bowel sound characteristics was made between these subgroups of patients. In the presence of an obstruction, the site of obstruction was identified and bowel calibre was also measured to correlate with bowel sounds. RESULTS: A total of 71 patients were studied during the period July 2009 to January 2011. Forty patients had acute bowel obstruction (27 small bowel obstruction and 13 large bowel obstruction), 11 had subacute bowel obstruction (eight in the small bowel and three in large bowel) and 20 had no bowel obstruction (diagnoses of other conditions were made). Twenty-five patients received surgical intervention (35.2%) during the same admission for acute abdominal conditions. A total of 426 recordings were made and 420 recordings were used for analysis. There was no significant difference in sound-to-sound interval, dominant frequency, and peak frequency among patients with acute bowel obstruction, subacute bowel obstruction, and no bowel obstruction. In acute large bowel obstruction, the sound duration was significantly longer (median 0.81 s vs 0.55 s, P = 0.021) and the dominant frequency was significantly higher (median 440 Hz vs 288 Hz, P = 0.003) when compared to acute small bowel obstruction. No significant difference was seen between acute large bowel obstruction and large bowel pseudo-obstruction. For patients with small bowel obstruction, the sound-to-sound interval was significantly longer in those who subsequently underwent surgery compared with those treated non-operatively (median 1.29 s vs 0.63 s, P < 0.001). There was no correlation between bowel calibre and bowel sound characteristics in both acute small bowel obstruction and acute large bowel obstruction. CONCLUSION: Auscultation of bowel sounds is non-specific for diagnosing bowel obstruction. Differences in sound characteristics between large bowel and small bowel obstruction may help determine the likely site of obstruction. PMID:22969233

Proposal of one-shot-type spectroscopic-tomography for non-invasive medical-measurement

NASA Astrophysics Data System (ADS)

Sato, Shun; Fujiwara, Masaru; Abeygunawardhana, Pradeep K. W.; Suzuki, Satoru; Nishiyama, Akira; Ishimaru, Ichiro

2013-06-01

The one-shot-type spectroscopic-tomography is proposed to develop the medical-patient-condition monitoring systems. The optical-setup is configured with the relative-inclined phase-shifter for improving the time resolution and the phase-shift array for improving visibility. We obtained the line-spectroscopic imaging and could recognize the Hg bright-line-spectrum that is a component of the light-source. The realization of the optical stethoscope for early diagnosis of cancer can be expected by obtaining the 2-dimensional spectroscopic distribution with rotating interferometer.

Comparison of lung sound transducers using a bioacoustic transducer testing system.

PubMed

Kraman, Steve S; Wodicka, George R; Pressler, Gary A; Pasterkamp, Hans

2006-08-01

Sensors used for lung sound research are generally designed by the investigators or adapted from devices used in related fields. Their relative characteristics have never been defined. We employed an artificial chest wall with a viscoelastic surface and a white noise signal generator as a stable source of sound to compare the frequency response and pulse waveform reproduction of a selection of devices used for lung sound research. We used spectral estimation techniques to determine frequency response and cross-correlation of pulses to determine pulse shape fidelity. The sensors evaluated were the Siemens EMT 25 C accelerometer (Siemens); PPG 201 accelerometer (PPG); Sony ECM-T150 electret condenser microphone with air coupler (air coupler; with cylindrical air chambers of 5-, 10-, and 15-mm diameter and conical air chamber of 10-mm diameter); Littman classic stethoscope head (Littman) connected to an electret condenser microphone; and the Andries Tek (Andries) electronic stethoscope. We found that the size and shape of the air coupler chamber to have no important effect on the detected sound. The Siemens, air coupler, and Littman performed similarly with relatively flat frequency responses from 200 to 1,200 Hz. The PPG had the broadest frequency response, with useful sensitivity extending to 4,000 Hz. The Andries' frequency response was the poorest above 1,000 Hz. Accuracy in reproducing pulses roughly corresponded with the high-frequency sensitivity of the sensors. We conclude that there are important differences among commonly used lung sound sensors that have to be defined to allow the comparison of data from different laboratories.

Surveillance of bacterial contamination in small animal veterinary hospitals with special focus on antimicrobial resistance and virulence traits of enterococci.

PubMed

KuKanich, Kate S; Ghosh, Anuradha; Skarbek, Jennifer V; Lothamer, Kale M; Zurek, Ludek

2012-02-15

To determine the prevalence of bacterial contamination on 4 surfaces of 4 types of standard equipment in small animal veterinary hospitals. Surveillance study. 10 small animal veterinary hospitals. Each hospital was visited 3 times at 4-month intervals; at each visit, a cage door, stethoscope, rectal thermometer, and mouth gag were swabbed. Swab samples were each plated onto media for culture of enterococci and organisms in the family Enterobacteriaceae. Enterococci were identified via a species-specific PCR assay and sodA gene sequencing; species of Enterobacteriaceae were identified with a biochemical test kit. Antimicrobial susceptibility was assessed via the disk diffusion method. Enterococci were screened for virulence traits and genotyped to assess clonality. Among the 10 hospitals, enterococci were isolated from cage doors in 7, from stethoscopes in 7, from thermometers in 6, and from mouth gags in 1; contamination with species of Enterobacteriaceae was rare. Enterococci were mainly represented by Enterococcus faecium (35.4%), Enterococcus faecalis (33.2%), and Enterococcus hirae (28.3%). Antimicrobial resistance was common in E. faecium, whereas virulence traits were present in 99% of E. faecalis isolates but not in E. faecium isolates. Clonal multidrug-resistant E. faecium was isolated from several surfaces at 1 hospital over multiple visits, whereas sporadic nonclonal contamination was detected in other hospitals. Contamination of surfaces in small animal veterinary hospitals with multidrug-resistant enterococci is a potential concern for pets and humans contacting these surfaces. Implementing precautions to minimize enterococcal contamination on these surfaces is recommended.

Heart murmurs recorded by a sensor based electronic stethoscope and e-mailed for remote assessment

PubMed Central

Dahl, L; Hasvold, P; Arild, E; Hasvold, T; Wren, C; Dahl, L; Hasvold, P; Arild, E; Hasvold, T

2002-01-01

Background: Heart murmurs are common in children, and they are often referred to a specialist for examination. A clinically innocent murmur does not need further investigation. The referral area of the University Hospital is large and sparsely populated. A new service for remote auscultation (telemedicine) of heart murmurs in children was established where heart sounds and short texts were sent as an attachment to e-mails. Aim: To assess the clinical quality of this method. Methods: Heart sounds from 47 patients with no murmur (n = 7), with innocent murmurs (n = 20), or with pathological murmurs (n = 20) were recorded using a sensor based stethoscope and e-mailed to a remote computer. The sounds were repeated, giving 100 cases that were randomly distributed on a compact disc. Four cardiologists assessed and categorised the cases as having "no murmur", "innocent murmur", or "pathological murmur", recorded the assessment time per case, their degree of certainty, and whether they recommended referral. Results: On average, 2.1 minutes were spent on each case. The mean sensitivity and specificity were 89.7% and 98.2% respectively, and the inter-observer and intra-observer variabilities were low (kappa 0.81 and 0.87), respectively. A total of 93.4% of cases with a pathological murmur and 12.6% of cases with an innocent murmur were recommended for referral. Conclusion: Telemedical referral of patients with heart murmurs for remote assessment by a cardiologist is safe and saves time. Skilled auscultation is adequate to detect patients with innocent murmurs. PMID:12244000

Clinical Examination Component of Telemedicine, Telehealth, mHealth, and Connected Health Medical Practices.

PubMed

Weinstein, Ronald S; Krupinski, Elizabeth A; Doarn, Charles R

2018-05-01

Telemedicine and telehealth are the practices of medicine at a distance. Performing the equivalent of a complete clinical examination by telemedicine would be unusual. However, components of a more traditional clinical examination are part of the telemedicine workup for specific conditions. Telemedicine clinical examinations are facilitated, and enhanced, through the integration of a class of medical devices referred to as telemedicine peripherals (eg, electronic stethoscopes, tele-ophthalmoscopes, video-otoscopes, and so forth). Direct-to-consumer telehealth is a rapidly expanding segment of the health care service industry. Copyright © 2018 Elsevier Inc. All rights reserved.

Induction of abnormal respiratory sounds by capsaicin in rats previously infected with Bordetella pertussis.

PubMed

Parton, R; Hall, E; Wardlaw, A C

1998-02-01

Sprague Dawley rats, previously infected with Phase-I Bordetella pertussis, developed more severe abnormal respiratory sounds than normal animals, but not coughing, when exposed to aerosolized capsaicin, one of several cough-inducing agents tested. Stethoscope examination suggested that greater production of pulmonary mucus might be occurring after capsaicin challenge of the infected animals, compared to the uninfected controls. Rats of three other strains gave characteristically different responses from the Sprague Dawleys. The administration of capsaicin to B. pertussis-infected rats may provide useful insights into the pathophysiology of excess mucus secretion in human pertussis.

The Navy Medical Department’s Workload Management System for Nursing (Patient Classification and Staffing Allocation). Self-Instructional Workbook

DTIC Science & Technology

1986-01-01

minal area, assess fetal heart tones with stethoscope , record FHTs, and remove equipment from area. or . Fetal Heart Tones, Doppler: Includes time to...activity to total 4 points. 5. Femoral OR pedal pulses OR fetal heart tones must be taken q 4 h . before you count the 2 points, but once again, since the... fetal heart tones OR tilt tests will count 2 points each if doneq 4 h or more frequently. If you had a patient with pedal pulses q 4 h AND fetal heart

The patient-surgeon relationship in the cyber era: communication and information.

PubMed

Blake, J Herman; Schwemmer, Mary Kay; Sade, Robert M

2012-11-01

From Laennec's invention of the stethoscope in 1816 to the recently introduced Sapien transcatheter aortic valve replacement, the increasing complexity of health care technology has altered the relationship between patients and physicians, usually for the better. Telemedicine, the provision of medical services through electronic media, has dramatically changed how the patient and physician interact and how medical care is delivered. Many studies of physicians' perceptions of electronic communication with patients have documented recognition of benefits as well as a consistent chorus of concerns about confidentiality, increased workload, inappropriate use, and medicolegal issues. Copyright © 2012 Elsevier Inc. All rights reserved.

Diagnostic validity of methods for assessment of swallowing sounds: a systematic review.

PubMed

Taveira, Karinna Veríssimo Meira; Santos, Rosane Sampaio; Leão, Bianca Lopes Cavalcante de; Neto, José Stechman; Pernambuco, Leandro; Silva, Letícia Korb da; De Luca Canto, Graziela; Porporatti, André Luís

2018-02-03

Oropharyngeal dysphagia is a highly prevalent comorbidity in neurological patients and presents a serious health threat, which may lead to outcomes of aspiration pneumonia, ranging from hospitalization to death. This assessment proposes a non-invasive, acoustic-based method to differentiate between individuals with and without signals of penetration and aspiration. This systematic review evaluated the diagnostic validity of different methods for assessment of swallowing sounds, when compared to Videofluroscopic of Swallowing Study (VFSS) to detect oropharyngeal dysphagia. Articles in which the primary objective was to evaluate the accuracy of swallowing sounds were searched in five electronic databases with no language or time limitations. Accuracy measurements described in the studies were transformed to construct receiver operating characteristic curves and forest plots with the aid of Review Manager v. 5.2 (The Nordic Cochrane Centre, Copenhagen, Denmark). The methodology of the selected studies was evaluated using the Quality Assessment Tool for Diagnostic Accuracy Studies-2. The final electronic search revealed 554 records, however only 3 studies met the inclusion criteria. The accuracy values (area under the curve) were 0.94 for microphone, 0.80 for Doppler, and 0.60 for stethoscope. Based on limited evidence and low methodological quality because few studies were included, with a small sample size, from all index testes found for this systematic review, Doppler showed excellent diagnostic accuracy for the discrimination of swallowing sounds, whereas microphone-reported good accuracy discrimination of swallowing sounds of dysphagic patients and stethoscope showed best screening test. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Utility of physical examination and comparison to echocardiography for cardiac diagnosis.

PubMed

Patel, Ashish; Tomar, Nitin Singh; Bharani, Anil

To find out the accuracy of cardiac auscultation using non-digital stethoscope in physical diagnosis of cardiac diseases. We enrolled 104 consecutive patients with abnormal cardiac auscultatory findings attending cardiology clinic and not previously evaluated by echocardiography. One time detailed cardiac physical examination followed by echocardiography within 1 month was undertaken. Agreement between two methods was calculated using mean pair percentage agreement, kappa statistics (κ) and calculation of 95% confidence interval (CI) for kappa statistics. Using kappa statistics, there was almost perfect agreement between cardiac auscultation and echocardiography for the detection of mitral stenosis (κ=0.865; CI 0.76-0.97) and ventricular septal defect (κ=0.872; CI=0.73-1.01). Substantial agreement was noted for aortic stenosis (κ=0.752; CI=0.56-0.94), pulmonary stenosis (κ=0.647; CI=0.33-0.97) and atrial septal defect (κ=0.646; CI=0.32-0.97), while moderate agreement was found for mitral regurgitation (κ=0.470; CI=0.30-0.64), aortic regurgitation (κ=0.456; CI=0.25-0.66) and tricuspid regurgitation (κ=0.575; CI=0.38-0.77). For combined mitral stenosis and mitral regurgitation lesions, almost perfect agreement was found for mitral stenosis (κ=0.842; CI=0.691-0.993) while fair agreement noted for mitral regurgitation (κ=0.255; CI=-0.008 to 0.518). Careful clinical auscultation using a stethoscope remains a valuable tool for cardiac diagnosis. Decision on initial diagnosis and management of valvular and congenital heart diseases should be based on clinical examination and integrating such information with echocardiography as required. Copyright © 2016 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

Development of an ultra-portable echo device connected to USB port.

PubMed

Saijo, Yoshifumi; Nitta, Shin-ichi; Kobayashi, Kazuto; Arai, Hitoshi; Nemoto, Yukiko

2004-04-01

In practical cardiology, a stethoscope based auscultation has been used to reveal the patient's clinical status. Recently, several hand-held echo devices are going on market and they are expected to play a role as "visible" auscultation instead of stethoscope. We have developed a portable and inexpensive echo device which can be used for screening of cardiac function. Two single element transducers were attached 180 degrees apart to a rotor with 14-mm diameter. The mechanical scanner, integrated circuits for transmitting and receiving ultrasonic signals and an A/D converter were encapsulated in a 150 x 40 mm probe weighing 200 g. The scan was started and the image was displayed on a Windows based personal computer (PC) as soon as the probe was connected to USB 2.0 port of the PC. The central frequency was available between 2.5 and 7.5 MHz, the image depth was 15 cm and the frame rate was 30/s. The estimated price of this ultra-portable ultrasound is about 3000 US dollars with software. For 69 cardiac patients with informed consent, image quality was compared with those obtained with basic range diagnostic echo machines. Left ventricular ejection fraction (EF) derived from normal M-mode image of standard machines (EFm) were compared with visual EF of the ultra-portable ultrasound device (EFv). The image quality was comparable to the basic range diagnostic echo machines although short axis view of aortic root was not clearly visualized because the probe was too large for intercostal approach. EFv agreed well with EFm. The ultra-portable ultrasound may provide useful information on screening and health care.

Recovery of vancomycin-resistant enterococci on fingertips and environmental surfaces.

PubMed

Noskin, G A; Stosor, V; Cooper, I; Peterson, L R

1995-10-01

To determine the recovery of vancomycin-resistant enterococci (VRE) on fingertips, gloved fingertips, and environmental surfaces commonly encountered in the healthcare setting, and to examine the importance of handwashing on the removal of these organisms. Two clinical isolates of VRE (Enterococcus faecalis and Enterococcus faecium) were inoculated onto the hands of healthy human volunteers and the following environmental surfaces: countertops, bedrails, telephones, and stethoscopes. Following inoculation, samples were obtained at various time intervals to determine rates of recovery of organisms. To evaluate the effects of handwashing on enterococcal recovery, two different soap preparations were tested. Hands were washed with water alone or with one of the soaps and water. The soap and water studies were performed with a 5-second and a 30-second wash. Both enterococcal strains survived for at least 60 minutes on gloved and ungloved fingertips. The E faecalis was recoverable from countertops for 5 days; the E faecium persisted for 7 days. For bedrails, both enterococcal species survived for 24 hours without significant reduction in colony counts. The bacteria persisted for 60 minutes on the telephone handpiece and for 30 minutes on the diaphragmatic surface of the stethoscope. A 5-second wash with water alone resulted in virtually no change in recovery of enterococci; a 30-second wash with water plus either soap was necessary to eradicate the bacteria from hands completely. VRE are capable of prolonged survival on hands, gloves, and environmental surfaces. Hands should be washed thoroughly and gloves removed following contact with patients infected or colonized with these multidrug-resistant bacteria. Finally, environmental surfaces may serve as potential reservoirs for nosocomial transmission of VRE and need to be considered when formulating institutional infection control policies.

A novel multimedia tool to improve bedside teaching of cardiac auscultation

PubMed Central

Woywodt, A; Herrmann, A; Kielstein, J; Haller, H; Haubitz, M; Purnhagen, H

2004-01-01

Training in cardiac auscultation is a core element of undergraduate teaching but recent studies have documented a remarkable decline in auscultatory skills. Therefore there is an interest in new ways to teach cardiac auscultation. In analogy to phonocardiography, an electronic system for simultaneous auscultation and visualisation of murmurs was sought. For this purpose, an electronic stethoscope was linked to a laptop computer and software created to visualise auscultatory findings. In a preliminary trial in undergraduate students, this approach greatly facilitated teaching. Amalgamating traditional phonocardiography with a multimedia approach, this system represents a novel tool for bedside teaching of cardiac auscultation. PMID:15192171

Lung sound analysis for wheeze episode detection.

PubMed

Jain, Abhishek; Vepa, Jithendra

2008-01-01

Listening and interpreting lung sounds by a stethoscope had been an important component of screening and diagnosing lung diseases. However this practice has always been vulnerable to poor audibility, inter-observer variations (between different physicians) and poor reproducibility. Thus computerized analysis of lung sounds for objective diagnosis of lung diseases is seen as a probable aid. In this paper we aim at automatic analysis of lung sounds for wheeze episode detection and quantification. The proposed algorithm integrates and analyses the set of parameters based on ATS (American Thoracic Society) definition of wheezes. It is very robust, computationally simple and yielded sensitivity of 84% and specificity of 86%.

A new cardiology patient simulator.

PubMed

Takashina, T; Shimizu, M; Katayama, H

1997-01-01

We report a new cardiology patient simulator developed through the application of new digital computer technology, capable of playing back selected physical findings (jugular-venous waves, arterial pulses of carotid, brachial, radial and femoral arteries, and cardiac impulses), as well as cardiac sounds, murmurs and respiratory sounds that have been prerecorded from actual patients. The examining physician uses an ordinary type of stethoscope. Four built-in speakers are located in the human-sized mannequin at the classic auscultatory sites (aortic, pulmonic, tricuspid and mitral). This compact and portable educational apparatus should facilitate medical training in the bedside cardiac examination, of physicians, medical students, nurses and paramedics throughout the world.

Prevention, not just treatment.

PubMed

Connors, G L; Hilling, L

1998-03-01

A tragic burden of disease, disability, and death has resulted from smoking. The role of pulmonary rehabilitation is not only in treatment and rehabilitation of lung disease but in the prevention of lung disease. The skills of the pulmonary rehabilitation specialist should be used in the earlier detection and prevention of lung disease through primary and secondary prevention. The spirometer must gain acceptance in the medical community as the early tool to evaluate lung health, not the chest radiograph or the stethoscope. The lung age formula and sputum pap smears are just a few of the evaluation tools used to detect and motivate susceptible individuals. Prevention is the key to enhancing lung health.

A Study to Determine the Most Cost-Effective Method of Delivering Obstetrical Care to All Eligible Beneficiaries within the Kenner Army Community Hospital’s Catchment Area

DTIC Science & Technology

1988-07-05

ONITOR FETAL 10952.72 651501C725660 I MNrITOR OXYGEN 783.92 651501C725692 I PLMP BREAST MECHANICAL 1106.39 651501C725694 I STETHOSCOPE ULTRASOJ’D...TODDLEP 1496.12 651501C725969 I MONITOR, PHYSIOLOGICAL SYST, EMSS 2258.21 651501C726026 I FETAL HEART MCONITOR 9937.20 651501C726162 I OXI ETER, PULSE...THERMWTER FARE𔃾-EIT ELECTRONIC W/-ARGER 303.55 651501C725211 I MONITOR FETAL PULSE 1305.42 651501C725442 2 PUMP INFUSION VOLLUETRIC 1834.71 65150IC725596 I

Establishing predictors for successfully planned endotracheal extubation.

PubMed

Lai, Chih-Cheng; Chen, Chin-Ming; Chiang, Shyh-Ren; Liu, Wei-Lun; Weng, Shih-Feng; Sung, Mei-I; Hsing, Shu-Chen; Cheng, Kuo-Chen

2016-10-01

The aim of this study was to establish predictors for successfully planned extubation, which can be followed by medical personnel. The patients who were admitted to the adult intensive care unit of a tertiary hospital and met the following criteria between January 2005 and December 2014 were collected retrospectively: intubation > 48 hours; and candidate for extubation. The patient characteristics, including disease severity, rapid shallow breath index (RSBI), maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), cuff leak test (CLT) before extubation, and outcome, were recorded. The CLT was classified as 2+ with audible flow without a stethoscope, 1+ with audible flow using a stethoscope, and negative (N) with no audible flow, even with a stethoscope. Failure to extubate was defined as reintubation within 48 hours. In total, 6583 patients were enrolled and 403 patients (6.1%) had extubation failures. Male patients dominated the patient cohort (4261 [64.7%]). The mean age was 64.5±16.3 years. The overall in-hospital mortality rate was 11.3%. The extubation failure rate for females was greater than males (7.7% vs 5.3%, P < 0.001). The group of patients who failed extubation were older (66.7 ± 14.4 vs 64.3 ± 16.4, P = 0.002), had higher APACHE II scores (16.8 ± 7.6 vs 15.9 ± 7.8, P = 0.023), lower coma scales (10.3 ± 3.7 vs 10.8 ± 3.7, P = 0.07), a higher RSBI (69.9 ± 37.3 vs 58.6 ± 30.3, P < 0.001), a lower MIP, and MEP (-35.6 ± 15.3 vs -37.8 ± 14.6, P = 0.0001 and 49.6 ± 28.4 vs 58.6 ± 30.2, P < 0.001, respectively), and a higher mortality rate (25.6% vs 10.5%, P < 0.001) compared to the successful extubation group. Based on multivariate logistic regression, a CLT of 2+ (odds ratio [OR] = 2.07, P < 0.001), a MEP ≥ 55 cmH2O (OR = 1.73, P < 0.001), and a RSBI < 68 breath/min/ml (OR = 1.57, P < 0.001) were independent predictors for successful extubation.This study identified 3 independent risk factors for successful extubation after a successful breathing trial, including a CLT of 2+, a MEP ≥ 55 cmH2O, and a RSBI < 68 breath/min/ml. Furthermore, a nomogram integrating these 3 parameters, which represented the combined consideration of the upper airway patentency, cough strength, and respiratory capacity, was developed to better predict extubation success.

Blood pressure evaluation using sphygmomanometry assisted by arterial pulse waveform detection by fiber Bragg grating pulse device

NASA Astrophysics Data System (ADS)

Sharath, Umesh; Sukreet, Raju; Apoorva, Girish; Asokan, Sundarrajan

2013-06-01

We report a blood pressure evaluation methodology by recording the radial arterial pulse waveform in real time using a fiber Bragg grating pulse device (FBGPD). Here, the pressure responses of the arterial pulse in the form of beat-to-beat pulse amplitude and arterial diametrical variations are monitored. Particularly, the unique signatures of pulse pressure variations have been recorded in the arterial pulse waveform, which indicate the systolic and diastolic blood pressure while the patient is subjected to the sphygmomanometric blood pressure examination. The proposed method of blood pressure evaluation using FBGPD has been validated with the auscultatory method of detecting the acoustic pulses (Korotkoff sounds) by an electronic stethoscope.

A systematic review of novel technology for monitoring infant and newborn heart rate.

PubMed

Kevat, Ajay C; Bullen, Denise V R; Davis, Peter G; Kamlin, C Omar F

2017-05-01

Heart rate (HR) is a vital sign for assessing the need for resuscitation. We performed a systematic review of studies assessing novel methods of measuring HR in newborns and infants in the neonatal unit. Two investigators completed independent literature searches. Identified papers were independently evaluated, and relevant data were extracted and analysed. This systematic review identified seven new technologies, including camera-based photoplethysmography, reflectance pulse oximetry, laser Doppler methods, capacitive sensors, piezoelectric sensors, electromyography and a digital stethoscope. Clinicians should be aware of several of these, which may become available for clinical use in the near future. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Thoracic auscultation in captive bottlenose dolphins (Tursiops truncatus), California sea lions (Zalophus californianus), and South African fur seals (Arctocephalus pusillus) with an electronic stethoscope.

PubMed

Scharpegge, Julia; Hartmann, Manuel García; Eulenberger, Klaus

2012-06-01

Thoracic auscultation is an important diagnostic method used in cases of suspected pulmonary disease in many species, as respiratory sounds contain significant information on the physiology and pathology of the lungs and upper airways. Respiratory diseases are frequent in marine mammals and are often listed as one of their main causes of death. The aim of this study was to investigate and report baseline parameters for the electronic-mediated thoracic auscultation of one cetacean species and two pinniped species in captivity. Respiratory sounds from 20 captive bottlenose dolphins (Tursiops truncatus), 6 California sea lions (Zalophus californianus), and 5 South African fur seals (Arctocephalus pusillus) were recorded with an electronic stethoscope. The sounds were analyzed for duration of the respiratory cycle, adventitious sounds, and peak frequencies of recorded sounds during expiration and inspiration as well as for sound intensity as reflected by waveform amplitude during the respiratory cycle. In respiratory cycles of the bottlenose dolphins' expiring "on command," the duration of the expiration was significantly shorter than the duration of the inspiration. In the examined pinnipeds of this study, there was no clear pattern concerning the duration of one breathing phase: Adventitious sounds were detected most often in bottlenose dolphins that were expiring on command and could be compared with "forced expiratory wheezes" in humans. This is the first report of forced expiratory wheezes in bottlenose dolphins; they can easily be misinterpreted as pathologic respiratory sounds. The peak frequencies of the respiratory sounds reached over 2,000 Hz in bottlenose dolphins and over 1,000 Hz in California sea lions and South African fur seals, but the variation of the frequency spectra was very high in all animals. To the authors' knowledge, this is the first systematic analysis of respiratory sounds of bottlenose dolphins and two species of pinnipeds.

Improved cardiovascular diagnostic accuracy by pocket size imaging device in non-cardiologic outpatients: the NaUSiCa (Naples Ultrasound Stethoscope in Cardiology) study

PubMed Central

2010-01-01

Miniaturization has evolved in the creation of a pocket-size imaging device which can be utilized as an ultrasound stethoscope. This study assessed the additional diagnostic power of pocket size device by both experts operators and trainees in comparison with physical examination and its appropriateness of use in comparison with standard echo machine in a non-cardiologic population. Three hundred four consecutive non cardiologic outpatients underwent a sequential assessment including physical examination, pocket size imaging device and standard Doppler-echo exam. Pocket size device was used by both expert operators and trainees (who received specific training before the beginning of the study). All the operators were requested to give only visual, qualitative insights on specific issues. All standard Doppler-echo exams were performed by expert operators. One hundred two pocket size device exams were performed by experts and two hundred two by trainees. The time duration of the pocket size device exam was 304 ± 117 sec. Diagnosis of cardiac abnormalities was made in 38.2% of cases by physical examination and in 69.7% of cases by physical examination + pocket size device (additional diagnostic power = 31.5%, p < 0.0001). The overall K between pocket size device and standard Doppler-echo was 0.67 in the pooled population (0.84 by experts and 0.58 by trainees). K was suboptimal for trainees in the eyeball evaluation of ejection fraction, left atrial dilation and right ventricular dilation. Overall sensitivity was 91% and specificity 76%. Sensitivity and specificity were lower in trainees than in experts. In conclusion, pocket size device showed a relevant additional diagnostic value in comparison with physical examination. Sensitivity and specificity were good in experts and suboptimal in trainees. Specificity was particularly influenced by the level of experience. Training programs are needed for pocket size device users. PMID:21110840

A simple computer-based measurement and analysis system of pulmonary auscultation sounds.

PubMed

Polat, Hüseyin; Güler, Inan

2004-12-01

Listening to various lung sounds has proven to be an important diagnostic tool for detecting and monitoring certain types of lung diseases. In this study a computer-based system has been designed for easy measurement and analysis of lung sound using the software package DasyLAB. The designed system presents the following features: it is able to digitally record the lung sounds which are captured with an electronic stethoscope plugged to a sound card on a portable computer, display the lung sound waveform for auscultation sites, record the lung sound into the ASCII format, acoustically reproduce the lung sound, edit and print the sound waveforms, display its time-expanded waveform, compute the Fast Fourier Transform (FFT), and display the power spectrum and spectrogram.

The lung exam.

PubMed

Loudon, R G

1987-06-01

Accurate diagnosis is essential for effective treatment. After history-taking, the physical examination is second in importance in assessing a pulmonary patient. The time-honored sequence of inspection, palpation, percussion, and auscultation is appropriate. Diagnostic tests are becoming more complex, more expensive, and more inclined to separate the patient and physician. The stethoscope is still the more commonly used diagnostic medical instrument, but it is not always used to best advantage. It is familiar, harmless, portable, and inexpensive. Its appropriate use improves medical practice and reduces costs. Improvements in sound recording and analysis techniques have spurred a renewed interest in lung sounds and their meaning. This is likely to lead to better understanding of what we hear, and perhaps to the development of new noninvasive diagnostic and monitoring techniques.

Maintaining the passion for pinards.

PubMed

Smith, Hannah

2013-09-01

Throughout my midwifery programme I have developed a passion for the use of pinards; a skill that may be lost within midwifery. It is often acknowledged that the use of pinard stethoscopes prior to the use of electronic devices is best practice (Royal College of Midwives (RCM) 2012), yet it is a practice that seems to be losing its place. This article aims to share some of the benefits of using a pinard and encourages the reader to reflect on their own feelings towards using this tool in practice. I will analyse whether or not there is still a value for pinards following an event I experienced whilst on clinical placement. This reflection uses an adapted version of Driscoll's Model of structured reflection (Driscoll 2000).

[Cardiology: is the smartphone era?

PubMed

Mandoli, Giulia Elena; D'Ascenzi, Flavio; Cameli, Matteo; Mondillo, Sergio

2017-12-01

The worldwide spread of smartphones has radically changed the habits of human life, allowing a 24/7 connection with other people. These changes have involved also Medicine with smartphones being able to simplify the clinical practice of physicians. The development of new external devices that can be connected to smartphones has further increased their use with mobile phones converted in portable electrocardiogram or echocardiogram machines. This extraordinary technological improvement seems to be partly in conflict with the classical tools available for the cardiologist, such as the "old" stethoscope that in 2016 had its 200th anniversary. This article focuses on the smartphone as a new tool available for the physicians, describing the most important potential uses and reporting an analysis of pros and cons of the smart-cardiology.

A stethoscope with wavelet separation of cardiac and respiratory sounds for real time telemedicine implemented on field-programmable gate array

NASA Astrophysics Data System (ADS)

Castro, Víctor M.; Muñoz, Nestor A.; Salazar, Antonio J.

2015-01-01

Auscultation is one of the most utilized physical examination procedures for listening to lung, heart and intestinal sounds during routine consults and emergencies. Heart and lung sounds overlap in the thorax. An algorithm was used to separate them based on the discrete wavelet transform with multi-resolution analysis, which decomposes the signal into approximations and details. The algorithm was implemented in software and in hardware to achieve real-time signal separation. The heart signal was found in detail eight and the lung signal in approximation six. The hardware was used to separate the signals with a delay of 256 ms. Sending wavelet decomposition data - instead of the separated full signa - allows telemedicine applications to function in real time over low-bandwidth communication channels.

[Intrapartum foetal monitoring: from stethoscope to ST analysis of the ECG].

PubMed

Westerhuis, Michelle E M H; Strasser, Sanne M; Moons, Karel G M; Mol, Ben Willem J; Visser, Gerard H A; Kwee, Anneke

2009-01-01

Since the 1970s, intrapartum monitoring of the distressed foetus has been managed by continuous registration of the foetal heart rate, together with uterine activity (cardiotocogram; CTG). Use of CTG without additional foetal information leads to unnecessary interventions because of the high number of false-positive signals. Foetal blood sampling (FBS) is a solution to this problem, but is not always consistently carried out. Automated ST analysis of the foetal electrocardiogram (STAN method), combined with the CTG, may lead to reduction of metabolic acidosis, fewer interventions and fewer foetal blood samples. A disadvantage of application of the STAN method is that it is based on visual interpretation of the CTG, with large inter- and intraobserver variability. In spite of this shortcoming the method may be promising.

Monitoring ventricular function at rest and during exercise with a nonimaging nuclear detector.

PubMed

Wagner, H N; Rigo, P; Baxter, R H; Alderson, P O; Douglass, K H; Housholder, D F

1979-05-01

A portable nonimaging device, the nuclear stethoscope, for measuring beat to beat ventricular time-activity curves in normal people and patients with heart disease, both at rest and during exercise, is being developed and evaluated. The latest device has several operating modes that facilitate left ventricular and background localization, measurement of transit times and automatic calculation and display of left ventricular ejection fraction. The correlation coefficient of left ventricular ejection fraction obtained with the device and with a camera-computer system was 0.92 in 35 subjects. During bicycle exercise the ejection fraction in 15 normal persons increased from 44 to 64 percent (P less than 0.001), whereas among 12 patients with heart disease it was unchanged in 5 and decreased in 7.

From planets to crops and back: Remote sensing makes sense

NASA Astrophysics Data System (ADS)

Mustard, John F.

2017-04-01

Remotely sensed data and the instruments that acquire them are core parts of Earth and planetary observation systems. They are used to quantify the Earth's interconnected systems, and remote sensing is the only way to get a daily, or more frequent, snapshot of the status of the Earth. It really is the Earth's stethoscope. In a similar manner remote sensing is the rock hammer of the planetary scientist and the only way comprehensive data sets can be acquired. To risk offending many remotely sensed data acquired across the electromagnetic spectrum, it is the tricorder to explore known and unknown planets. Arriving where we are today in the use of remotely sensed data in the solar system has been a continually evolving synergy between Earth observation, planetary exploration, and fundamental laboratory work.

Bedside cardiac examination: constancy in a sea of change.

PubMed

Richardson, T R; Moody, J M

2000-11-01

The general trend in the recent literature has been to highlight the difficulties and shortcomings of the physical examination and to attribute these difficulties to deficiencies in training rather than to intrinsic weaknesses in auscultation itself. The call is for better training. Given the advice of the authors mentioned above, individual training may be warranted at the postgraduate level and in the large community of practicing internists and cardiologists. Although not proven, it is likely that individual training with computer technology, audiotape instruction, or simulator technology such as described in the following paragraphs would be effective at improving bedside clinical diagnosis and cost-effective patient care in the postgraduate, continuing medical education setting. The advances in auscultation during the last few years have been more incremental than fundamental. There is ongoing research into the mechanism of production of S3 and S4, and mathematical modeling techniques have recently been used with some success in evaluating the vibrations of S3 and S4 as forced, damped oscillations of a viscoelastic system. Analysis of sound energy with the technique of spectral waveform analysis, which investigates the frequency content of sound signals, has been used for many years in the study of cardiovascular sound. By the use of various methods of mathematical analysis, investigators have found potentially useful information in spectral sound patterns of prosthetic valves, murmur characteristics, and even potentially hemodynamic information from heart sounds. Despite the mathematical advances, there are still disturbing drawbacks to some of the analytic techniques, such as the production of mathematical terms containing "negative energy." Although the potential of obtaining significant clinical information from spectral analysis of heart sound recordings is attractive, the clinical usefulness of such techniques remains virtually nonexistent. Similar to the recent advances in auscultation, the technical advances in the design of the stethoscope have also been more incremental than fundamental. There are at least 3 recently introduced electronic stethoscopes that have the capability of amplification and filtration and that claim noise reduction. Because their introduction is recent, no information is available in the peer-review literature regarding their clinical performance; therefore their place in the clinical arena remains to be elucidated--perhaps a boon for patient care providers with specific hearing defects and perhaps useful in noisy clinical environments. Peer-review literature has not shown clear superiority of one type of acoustic stethoscope over another. The teaching of auscultation has been an area of recognized importance in patient care since the inception of auscultation as a medical art. Attempts to facilitate practitioner learning in the performance and interpretation of auscultation have advanced through the decades limited only by the technical infrastructure of the day. The availability of recorded heart sounds and murmurs appeared shortly after the availability of recording and playback devices, with first vinyl and later tape recordings. In 1974, technology was employed to create a virtual patient named "Harvey," an engineered cardiology patient simulator that reproduces many of the physical findings of the cardiology examination. Later, with the advent of commercially available CD-ROM devices, newer, better-integrated teaching devices have been developed, some of them outstanding in their clarity and quality. Despite the obvious value of such instructional aids that are best used in the individual setting, there is evidence that the classroom is still of significant value in teaching auscultation. However, nowhere else in the practice of medicine is a mentor approach more valuable than in learning auscultation. (ABSTRACT TRUNCATED)

Patients with stable chronic obstructive pulmonary disease can safely undergo intravenous dipyridamole thallium-201 imaging.

PubMed

Shaffer, J; Simbartl, L; Render, M L; Snow, E; Chaney, C; Nishiyama, H; Rauf, G C; Wexler, L F

1998-08-01

Patients with chronic obstructive pulmonary disease are usually excluded from intravenous dipyridamole thallium-201 testing. We developed a nurse-administered protocol to screen and pretreat patients so they could be safely tested. We prospectively screened patients referred for intravenous dipyridamole thallium testing and retrospectively reviewed a comparison group of patients who had undergone intravenous dipyridamole testing before our bronchospasm protocol. We studied 492 consecutive patients referred for intravenous dipyridamole thallium testing, separating those with complete data (n = 451) into two groups: group A (n = 72), patients assessed to be at risk for intravenous dipyridamole-induced bronchospasm who received our bronchospasm treatment protocol; and group B (n = 379), patients assessed to be free of risk, who did not receive our bronchospasm protocol. Group C (n = 89) was a retrospective comparison group of patients who had undergone intravenous dipyridamole testing before initiation of the protocol. Patients were considered at risk for an adverse event if any of the following were present: peak flow < or =400 ml at the time of the test (spirometry by nurse) that increased to >400 ml after bronchodilator treatment, wheezing audible with stethoscope, history of chronic obstructive pulmonary disease or asthma or dyspnea on exertion at less than four blocks, or resting respiratory rate >18 breaths/min. The test was considered contraindicated if resting oxygen saturation was <85%, respiratory rate < or =36 breaths/min, or peak flow measured by peak flowmeter <400 ml after bronchodilator inhalant (albuterol or metaproterenol sulfate by spacer) at a dose of up to six puffs. One minute after injections of thallium-201, patients at risk were given 50 mg aminophylline by slow intravenous injection. We looked for major and minor adverse effects and divided them into three categories: (1) minor events (transient headache, abdominal discomfort, or nausea), wheezing (audible by stethoscope but without marked respiratory distress), (2) marked events (severe bronchospasm or severe ischemia defined as wheezing audible with or without stethoscope, respiratory rate >20 breaths/min or increased by 10 from pretest evaluation, oxygen desaturation to <90%, hypoventilation [reduced respiratory rate with decreased mental status], respiratory arrest, chest pain, horizontal ST-segment depression > or =1 mm on the electrocardiogram in any lead, symptomatic hypotension), or (3) other intravenous dipyridamole-induced side effects (persistent headache, dizziness, flushing, nausea, dyspnea, and ischemic chest pain) or anginal equivalent. The protocol properly identified patients with impaired pulmonary function. There was no difference in the frequency of adverse marked events among groups A, B, or C (1 % vs 4% vs 2%, p = 0.25). Patients in group A had more minor side effects than those in group B (53% vs 35%, p = 0.004). Specifically, patients in group A were more likely to wheeze (39% vs 1 %, p = <0.001), but wheezing in group A was self-limited or responded to treatment as described in the protocol. The prevalence of positive thallium-201 scans in group A (44%) compared with group C (49%) was not different (p = 0.15). A nurse-administered risk assessment and pretreatment protocol (1) properly identified patients with impaired pulmonary function, (2) permitted completion of intravenous dipyridamole testing in patients at risk for bronchospasm without an increased incidence of marked adverse events, and (3) did not appear to influence the interpretation of the thallium test.

Intermittent detection of fetal heart rate abnormalities identify infants at greatest risk for fresh stillbirths, birth asphyxia, neonatal resuscitation, and early neonatal deaths in a limited-resource setting: a prospective descriptive observational study at Haydom Lutheran Hospital.

PubMed

Langli Ersdal, Hege; Mduma, Estomih; Svensen, Erling; Sundby, Johanne; Perlman, Jeffrey

2012-01-01

Intermittent fetal heart rate (FHR) monitoring during labor using an acoustic stethoscope is the most frequent method for fetal assessment of well-being in low- and middle-income countries. Evidence concerning reliability and efficacy of this technique is almost nonexistent. To determine the value of routine intermittent FHR monitoring during labor in the detection of FHR abnormalities, and the relationship of abnormalities to the subsequent fresh stillbirths (FSB), birth asphyxia (BA), need for neonatal face mask ventilation (FMV), and neonatal deaths within 24 h. This is a descriptive observational study in a delivery room from November 2009 through December 2011. Research assistants/observers (n = 14) prospectively observed every delivery and recorded labor information including FHR and interventions, neonatal information including responses in the delivery room, and fetal/neonatal outcomes (FSB, death within 24 h, admission neonatal area, or normal). 10,271 infants were born. FHR was abnormal (i.e. <120 or >160 beats/min) in 279 fetuses (2.7%) and absent in 200 (1.9%). Postnatal outcomes included FSB in 159 (1.5%), need for FMV in 695 (6.8%), BA (i.e. 5-min Apgar score <7) in 69 (0.7%), and deaths in 89 (0.9%). Abnormal FHR was associated with labor complications (OR = 31.4; 95% CI: 23.1-42.8), increased need for FMV (OR = 7.8; 95% CI: 5.9-10.1), BA (OR = 21.7; 95% CI: 12.7-37.0), deaths (OR = 9.9; 95% CI: 5.6-17.5), and FSB (OR = 35; 95% CI: 20.3-60.4). An undetected FHR predicted FSB (OR = 1,983; 95% CI: 922-4,264). Intermittent detection of an absent or abnormal FHR using a fetal stethoscope is associated with FSB, increased need for neonatal resuscitation, BA, and neonatal death in a limited-resource setting. The likelihood of an abnormal FHR is magnified with labor complications. Copyright © 2012 S. Karger AG, Basel.

The history of COPD.

PubMed

Petty, Thomas L

2006-01-01

The evolution of knowledge concerning COPD and its components--emphysema, chronic bronchitis, and asthmatic bronchitis--covers 200 years. The stethoscope and spirometer became important early tools in diagnosis and assessment. Spirometry remains the most effective means of identification and assessment of the course of COPD and responses to therapy, and is grossly underused for this purpose. Knowledge of the pathogenesis, course and prognosis, and new approaches to therapy have dramatically improved our understanding of this important clinical entity. Smoking cessation improves the early course of disease. Long-term oxygen improves the length and quality of life in selected patients with hypoxemia. Surgery benefits a select few. Today, COPD is a steadily growing global healthcare problem, with increasing morbidity and mortality. Early identification and prevention, and treatment of emerging stages of disease through smoking cessation and a growing number of bronchoactive drugs promises to change the outcome.

[Thoracic ultrasound: the pneumologist's new stethoscope].

PubMed

Heinen, V; Duysinx, B; Corhay, J L; Louis, R

2012-10-01

We now have access to a large library of publications validating transparietal thoracic echography in various clinical situations. Parietal lesions, including osteolysis, can be detected and biopsied during the thoracic ultrasound (TUS) examination. To evaluate the parietal extension of lung cancers, TUS has proved superior to tomodensitometry. Pleural effusions can be easily diagnosed and aspirated. Pneumothoraces can be detected using well defined lung artifacts with a high frequency probe. Pleural and peripheral lung nodules can be detected and biopsied with real time visualization; the procedure is safe and accurate. Lung consolidations with a pleural contact can be diagnosed; this is particularly useful for pregnant women. In conclusion, TUS is a precious diagnostic tool for chosen applications, and can help to guide interventional procedures. The portable devices are also very useful for bedridden patients or for out of hospital use.

Landmarks in Allergy during the 19th Century.

PubMed

Kay, A Barry

2014-01-01

There were remarkable achievements in the 19th century in our understanding of the cells of the allergic response, the clear descriptions of hay fever and asthma, as well as the role of pollen in seasonal rhinitis. Although allergy as a concept was not developed until well into the 20th century, the foundations of our present understanding of these diseases were laid in the 1800s. The outstanding physicians and scientists of this time included Paul Ehrlich (who described mast cells, eosinophils and basophils), John Bostock (who provided the first detailed account of hay fever), Charles Blackley (who showed that pollen was the cause of hay fever), Morrill Wyman (who demonstrated that autumnal catarrh was due to ragweed pollen), Henry Hide Salter (who made the first classic description of asthma) and Henri Laënnec (the inventor of the stethoscope). © 2014 S. Karger AG, Basel.

Arterial endothelial function measurement method and apparatus

DOEpatents

Maltz, Jonathan S; Budinger, Thomas F

2014-03-04

A "relaxoscope" (100) detects the degree of arterial endothelial function. Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. An artery (115), such as the brachial artery (BA) is measured for diameter before and after several minutes of either vasoconstriction or vasorelaxation. The change in arterial diameter is a measure of flow-mediated vasomodification (FMVM). The relaxoscope induces an artificial pulse (128) at a superficial radial artery (115) via a linear actuator (120). An ultrasonic Doppler stethoscope (130) detects this pulse 10-20 cm proximal to the point of pulse induction (125). The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before (160) and after arterial diameter change (170), FMVM may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness.

Biophysics of Heart Sounds and Its Application to Clinical Auscultation

PubMed Central

Faber, J. Job; Burton, Alan C.

1964-01-01

Much research has been carried out recently into the means by which heart sounds and murmurs reach the stethoscope from their point of origin. Heart sounds originate as vibrations of the cardiac valves and travel as transverse vibrations with low velocity over the walls of the ventricles and great vessels. Where these structures are in contact with the thoracic surface they emerge, at the `auscultatory areas', and spread like ripples over the chest surface. Murmurs originate in the cavities receiving the blood stream, and are loudest in the cavity that is less distensible. Frequency, damping in transit and the possible misinterpretation of apparent `splitting' seen in phonocardiographic records are discussed. This basic knowledge of modes of transmission allows the interpretation of unusual locations of auscultatory areas in disease states, and explains some puzzling findings obtained with microphones mounted on cardiac catheters. ImagesFig. 3Fig. 6 PMID:14174528

Smart phone monitoring of second heart sound split.

PubMed

Thiyagaraja, Shanti R; Vempati, Jagannadh; Dantu, Ram; Sarma, Tom; Dantu, Siva

2014-01-01

Heart Auscultation (listening to heart sounds) is the basic element of cardiac diagnosis. The interpretation of these sounds is a difficult skill to acquire. In this work we have developed an application to detect, monitor, and analyze the split in second heart sound (S2) using a smart phone. The application records the heartbeat using a stethoscope connected to the smart phone. The audio signal is converted into the frequency domain using Fast Fourier Transform to detect the first and second heart sounds (S1 and S2). S2 is extracted and fed into the Discrete Wavelet Transform (DWT) and then to Continuous Wavelet Transform (CWT) to detect the Aortic (A2) and the Pulmonic (P2) components, which are used to calculate the split in S2. With our application, users can continuously monitor their second heart sound irrespective of ages and check for a split in their hearts with a low-cost, easily available equipment.

A phase I study of human natural interferon-beta in cancer patients.

PubMed

Liberati, A M; Biscottini, B; Fizzotti, M; Schippa, M; De Angelis, V; Senatore, M; Vittori, O; Teggia, L; Natali, R; Palmisano, L

1989-06-01

In this phase I study 15 patients with metastatic tumors were given interferon (IFN)-beta by i.v. bolus injections. Twelve individual doses of 1, 2, 3.3, 5, 7, 9, 12, 16, 21, 27, 35, and 46 x 10(6) IU were administered every other day. The single maximal tolerated dose ranged from 9 to 46 x 10(6) IU. Eight patients tolerated the dose of 46 x 10(6) IU without side effects. Disturbances of cardiac rhythm were observed, but were closely related temporally to severe chills and appeared to be the consequence of adrenergic stimulation associated with this side-effect. In addition, no significant variations in the left ventricular function as assessed by nuclear stethoscope were observed. Neurotoxicity was not a major side-effect. The toxicity of IFN-beta given as scheduled in this study was significant, but acceptable.

Noise Reduction in Breath Sound Files Using Wavelet Transform Based Filter

NASA Astrophysics Data System (ADS)

Syahputra, M. F.; Situmeang, S. I. G.; Rahmat, R. F.; Budiarto, R.

2017-04-01

The development of science and technology in the field of healthcare increasingly provides convenience in diagnosing respiratory system problem. Recording the breath sounds is one example of these developments. Breath sounds are recorded using a digital stethoscope, and then stored in a file with sound format. This breath sounds will be analyzed by health practitioners to diagnose the symptoms of disease or illness. However, the breath sounds is not free from interference signals. Therefore, noise filter or signal interference reduction system is required so that breath sounds component which contains information signal can be clarified. In this study, we designed a filter called a wavelet transform based filter. The filter that is designed in this study is using Daubechies wavelet with four wavelet transform coefficients. Based on the testing of the ten types of breath sounds data, the data is obtained in the largest SNRdB bronchial for 74.3685 decibels.

Automated lung sound analysis for detecting pulmonary abnormalities.

PubMed

Datta, Shreyasi; Dutta Choudhury, Anirban; Deshpande, Parijat; Bhattacharya, Sakyajit; Pal, Arpan

2017-07-01

Identification of pulmonary diseases comprises of accurate auscultation as well as elaborate and expensive pulmonary function tests. Prior arts have shown that pulmonary diseases lead to abnormal lung sounds such as wheezes and crackles. This paper introduces novel spectral and spectrogram features, which are further refined by Maximal Information Coefficient, leading to the classification of healthy and abnormal lung sounds. A balanced lung sound dataset, consisting of publicly available data and data collected with a low-cost in-house digital stethoscope are used. The performance of the classifier is validated over several randomly selected non-overlapping training and validation samples and tested on separate subjects for two separate test cases: (a) overlapping and (b) non-overlapping data sources in training and testing. The results reveal that the proposed method sustains an accuracy of 80% even for non-overlapping data sources in training and testing.

Respiratory assessment.

PubMed

Simpson, Heidi

The ability to carry out and document a full respiratory assessment is an essential skill for all nurses. The elements included are: an initial assessment, history taking, inspection, palpation, percussion, auscultation and further investigations. A prompt initial assessment allows immediate evaluation of severity of illness and appropriate treatment measures may warrant instigation at this point. Following this, a comprehensive patient history will be elicited. Clinical examination of the patient follows and involves inspection, palpation, percussion and auscultation. At this point, consideration must be given to preparation of a light, warm, quiet, private environment for examination and suitable patient positioning. Inspection is a comprehensive visual assessment, while palpation involves using touch to gather information. The next stages are percussion and auscultation. While percussion is striking the chest to determine the state of underlying tissues, auscultation entails listening to and interpreting sound transmission through the chest wall via a stethoscope. Finally, further investigations may be necessary to confirm or negate suspected diagnoses.

Expiratory lung crackles in patients with fibrosing alveolitis.

PubMed

Walshaw, M J; Nisar, M; Pearson, M G; Calverley, P M; Earis, J E

1990-02-01

Inspiratory lung crackles are a diagnostic feature of interstitial pulmonary fibrosis, but expiratory crackles are not well documented. In a phonopneumographic study of 13 patients with fibrosing alveolitis, expiratory crackles were audible with the stethoscope in 12. Phonopneumographic analysis of these 12 patients showed the crackles to be fine with the initial wave deflection of the expiratory and inspiratory crackles in opposite directions. They were few in number, occurred predominantly in mid- and late expiration, and were not affected by varying the volume history or by breath holding maneuvers. These observations support the theory that some crackles are produced by vibration of the walls of peripheral airways. In addition, this group of patients showed a significant correlation between the number of expiratory crackles and the reduction in predicted transfer factor, suggesting that expiratory crackles may be a clinical indicator of the severity of disease in fibrosing alveolitis.

The health professional's role in preventing nosocomial infections

PubMed Central

Saloojee, H; Steenhoff, A

2001-01-01

Despite their best intentions, health professionals sometimes act as vectors of disease, disseminating new infections among their unsuspecting clients. Attention to simple preventive strategies may significantly reduce disease transmission rates. Frequent hand washing remains the single most important intervention in infection control. However, identifying mechanisms to ensure compliance by health professionals remains a perplexing problem. Gloves, gowns, and masks have a role in preventing infections, but are often used inappropriately, increasing service costs unnecessarily. While virulent microorganisms can be cultured from stethoscopes and white coats, their role in disease transmission remains undefined. There is greater consensus about sterile insertion techniques for intravascular catheters—a common source of infections—and their care. By following a few simple rules identified in this review, health professionals may prevent much unnecessary medical and financial distress to their patients.


Keywords: infection control; cross infection; hand washing; catheterisation PMID:11123387

Infrared thermography for detection of laminar-turbulent transition in low-speed wind tunnel testing

NASA Astrophysics Data System (ADS)

Joseph, Liselle A.; Borgoltz, Aurelien; Devenport, William

2016-05-01

This work presents the details of a system for experimentally identifying laminar-to-turbulent transition using infrared thermography applied to large, metal models in low-speed wind tunnel tests. Key elements of the transition detection system include infrared cameras with sensitivity in the 7.5- to 14.0-µm spectral range and a thin, insulating coat for the model. The fidelity of the system was validated through experiments on two wind-turbine blade airfoil sections tested at Reynolds numbers between Re = 1.5 × 106 and 3 × 106. Results compare well with measurements from surface pressure distributions and stethoscope observations. However, the infrared-based system provides data over a much broader range of conditions and locations on the model. This paper chronicles the design, implementation and validation of the infrared transition detection system, a subject which has not been widely detailed in the literature to date.

Media images of physicians and nurses in the United States.

PubMed

Krantzler, N J

1986-01-01

This paper analyzes images of physicians and nurses presented in advertisements in the medical and nursing journals JAMA (Journal of the American Medical Association) and AJN (American Journal of Nursing). Advertisements are viewed as hyper-ritualized displays of symbols and rituals associated with medical and nursing practice, both reflecting and reaffirming stereotypes and beliefs that are widely held in the society at large. Trends over the past few decades show that medical advertisements are dropping some traditional symbols (such as the white coat and stethoscope) in favor of depicting science-in-action and high technology. Nursing advertisements, however, are more frequently utilizing the symbols formerly reserved for physicians. Both physicians and nurses are depicted in their respective journals as existing largely independent of one another. While these advertisements clearly do not depict social reality, they present a fictionalized version which reflects and reproduces some of the expressed ideals in medical and nursing practice.

A robust dataset-agnostic heart disease classifier from Phonocardiogram.

PubMed

Banerjee, Rohan; Dutta Choudhury, Anirban; Deshpande, Parijat; Bhattacharya, Sakyajit; Pal, Arpan; Mandana, K M

2017-07-01

Automatic classification of normal and abnormal heart sounds is a popular area of research. However, building a robust algorithm unaffected by signal quality and patient demography is a challenge. In this paper we have analysed a wide list of Phonocardiogram (PCG) features in time and frequency domain along with morphological and statistical features to construct a robust and discriminative feature set for dataset-agnostic classification of normal and cardiac patients. The large and open access database, made available in Physionet 2016 challenge was used for feature selection, internal validation and creation of training models. A second dataset of 41 PCG segments, collected using our in-house smart phone based digital stethoscope from an Indian hospital was used for performance evaluation. Our proposed methodology yielded sensitivity and specificity scores of 0.76 and 0.75 respectively on the test dataset in classifying cardiovascular diseases. The methodology also outperformed three popular prior art approaches, when applied on the same dataset.

Ten good reasons to practice ultrasound in critical care.

PubMed

Lichtenstein, Daniel; van Hooland, Simon; Elbers, Paul; Malbrain, Manu L N G

2014-01-01

Over the past decade, critical care ultrasound has gained its place in the armamentarium of monitoring tools. A greater understanding of lung, abdominal, and vascular ultrasound plus easier access to portable machines have revolutionised the bedside assessment of our ICU patients. Because ultrasound is not only a diagnostic test, but can also be seen as a component of the physical exam, it has the potential to become the stethoscope of the 21st century. Critical care ultrasound is a combination of simple protocols, with lung ultrasound being a basic application, allowing assessment of urgent diagnoses in combination with therapeutic decisions. The LUCI (Lung Ultrasound in the Critically Ill) consists of the identification of ten signs: the bat sign (pleural line); lung sliding (seashore sign); the A-lines (horizontal artefact); the quad sign and sinusoid sign indicating pleural effusion; the fractal and tissue-like sign indicating lung consolidation; the B-lines and lung rockets indicating interstitial syndromes; abolished lung sliding with the stratosphere sign suggesting pneumothorax; and the lung point indicating pneumothorax. Two more signs, the lung pulse and the dynamic air bronchogram, are used to distinguish atelectasis from pneumonia. The BLUE protocol (Bedside Lung Ultrasound in Emergency) is a fast protocol (< 3 minutes), also including a vascular (venous) analysis allowing differential diagnosis in patients with acute respiratory failure. With this protocol, it becomes possible to differentiate between pulmonary oedema, pulmonary embolism, pneumonia, chronic obstructive pulmonary disease, asthma, and pneumothorax, each showing specific ultrasound patterns and profiles. The FALLS protocol (Fluid Administration Limited by Lung Sonography) adapts the BLUE protocol to be used in patients with acute circulatory failure. It makes a sequential search for obstructive, cardiogenic, hypovolemic, and distributive shock using simple real-time echocardiography in combination with lung ultrasound, with the appearance of B-lines considered to be the endpoint for fluid therapy. An advantage of lung ultrasound is that the patient is not exposed to radiation, and so the LUCI-FLR project (LUCI favouring limitation of radiation) can be unfolded in trauma patients. Although it has been practiced for 25 years, critical care ultrasound is a relatively young but expanding discipline and can be seen as the stethoscope of the modern intensivist. In this review, the usefulness and advantages of ultrasound in the critical care setting are discussed in ten points. The emphasis is on a holistic approach, with a central role for lung ultrasound.

A description of externally recorded womb sounds in human subjects during gestation

PubMed Central

Daland, Robert; Kesavan, Kalpashri; Macey, Paul M.; Zeltzer, Lonnie; Harper, Ronald M.

2018-01-01

Objective Reducing environmental noise benefits premature infants in neonatal intensive care units (NICU), but excessive reduction may lead to sensory deprivation, compromising development. Instead of minimal noise levels, environments that mimic intrauterine soundscapes may facilitate infant development by providing a sound environment reflecting fetal life. This soundscape may support autonomic and emotional development in preterm infants. We aimed to assess the efficacy and feasibility of external non-invasive recordings in pregnant women, endeavoring to capture intra-abdominal or womb sounds during pregnancy with electronic stethoscopes and build a womb sound library to assess sound trends with gestational development. We also compared these sounds to popular commercial womb sounds marketed to new parents. Study design Intra-abdominal sounds from 50 mothers in their second and third trimester (13 to 40 weeks) of pregnancy were recorded for 6 minutes in a quiet clinic room with 4 electronic stethoscopes, placed in the right upper and lower quadrants, and left upper and lower quadrants of the abdomen. These recording were partitioned into 2-minute intervals in three different positions: standing, sitting and lying supine. Maternal and gestational age, Body Mass Index (BMI) and time since last meal were collected during recordings. Recordings were analyzed using long-term average spectral and waveform analysis, and compared to sounds from non-pregnant abdomens and commercially-marketed womb sounds selected for their availability, popularity, and claims they mimic the intrauterine environment. Results Maternal sounds shared certain common characteristics, but varied with gestational age. With fetal development, the maternal abdomen filtered high (500–5,000 Hz) and mid-frequency (100–500 Hz) energy bands, but no change appeared in contributions from low-frequency signals (10–100 Hz) with gestational age. Variation appeared between mothers, suggesting a resonant chamber role for intra-abdominal space. Compared to commercially-marketed sounds, womb signals were dominated by bowel sounds, were of lower frequency, and showed more variation in intensity. Conclusions High-fidelity intra-abdominal or womb sounds during pregnancy can be recorded non-invasively. Recordings vary with gestational age, and show a predominance of low frequency noise and bowel sounds which are distinct from popular commercial products. Such recordings may be utilized to determine whether sounds influence preterm infant development in the NICU. PMID:29746604

A description of externally recorded womb sounds in human subjects during gestation.

PubMed

Parga, Joanna J; Daland, Robert; Kesavan, Kalpashri; Macey, Paul M; Zeltzer, Lonnie; Harper, Ronald M

2018-01-01

Reducing environmental noise benefits premature infants in neonatal intensive care units (NICU), but excessive reduction may lead to sensory deprivation, compromising development. Instead of minimal noise levels, environments that mimic intrauterine soundscapes may facilitate infant development by providing a sound environment reflecting fetal life. This soundscape may support autonomic and emotional development in preterm infants. We aimed to assess the efficacy and feasibility of external non-invasive recordings in pregnant women, endeavoring to capture intra-abdominal or womb sounds during pregnancy with electronic stethoscopes and build a womb sound library to assess sound trends with gestational development. We also compared these sounds to popular commercial womb sounds marketed to new parents. Intra-abdominal sounds from 50 mothers in their second and third trimester (13 to 40 weeks) of pregnancy were recorded for 6 minutes in a quiet clinic room with 4 electronic stethoscopes, placed in the right upper and lower quadrants, and left upper and lower quadrants of the abdomen. These recording were partitioned into 2-minute intervals in three different positions: standing, sitting and lying supine. Maternal and gestational age, Body Mass Index (BMI) and time since last meal were collected during recordings. Recordings were analyzed using long-term average spectral and waveform analysis, and compared to sounds from non-pregnant abdomens and commercially-marketed womb sounds selected for their availability, popularity, and claims they mimic the intrauterine environment. Maternal sounds shared certain common characteristics, but varied with gestational age. With fetal development, the maternal abdomen filtered high (500-5,000 Hz) and mid-frequency (100-500 Hz) energy bands, but no change appeared in contributions from low-frequency signals (10-100 Hz) with gestational age. Variation appeared between mothers, suggesting a resonant chamber role for intra-abdominal space. Compared to commercially-marketed sounds, womb signals were dominated by bowel sounds, were of lower frequency, and showed more variation in intensity. High-fidelity intra-abdominal or womb sounds during pregnancy can be recorded non-invasively. Recordings vary with gestational age, and show a predominance of low frequency noise and bowel sounds which are distinct from popular commercial products. Such recordings may be utilized to determine whether sounds influence preterm infant development in the NICU.

In the Balance:

PubMed Central

Weaver, Lawrence T.

2010-01-01

Summary The nineteenth century saw the incorporation of technology, such as the stethoscope, microscope, and thermometer, into clinical medicine. An instrument that has received less attention in the history of the role of technology in medicine is the weighing balance, or scale. Although not new to nineteenth-century medicine, it played an important part in the rise of the numerical method and its application to the development and shaping of pediatrics. This article explores the origin and development of the weighing of babies. During its clinical and scientific adoption, this simple procedure was refined and applied in a number of increasingly sophisticated and far-reaching ways: as a measure of the dimensions of the fetus and newborn, as an index of the viability of the newborn, as a means of estimating milk intake, as a way of distinguishing normality from abnormality, as a summary measure of infant health, and as an instrument of mass surveillance. In so doing it changed the way in which medical care was delivered to infants. PMID:20632732

Study on the availability of physical infrastructure and manpower facilities in sub-centers of Chittoor district of Andhra Pradesh.

PubMed

Reddy, N Bayapa; Prabhu, G Ravi; Sai, T S R

2012-01-01

The sub-centers (SCs) are under constant criticism for their inability to deliver quality services due to the nonavailability of adequate infrastructure, manpower and supply of drugs.A cross-sectional study was conducted in Chittoor District of Andhra Pradesh to assess the availability of physical infrastructure and manpower in the SCs. A total of 34 SCs were selected by multistage and stratified random sampling technique. The data was statistically analyzed by using Microsoft Excel. The deficiency in the availability of health workers male and female were found to be 67.7% and 27.5%, respectively. The residential facility for health workers was available only in 26.4% SCs. Only 20.6% of SCs had stethoscope and B.P apparatus. The physical infrastructure and manpower availability at the SCs needs considerable improvement as per the Indian Public Health Standard (IPHS). Facilities to conduct the normal delivery and 24-hours emergency referral services need to be addressed at the earliest.

Automated Blood Pressure Measurement

NASA Technical Reports Server (NTRS)

1978-01-01

The Vital-2 unit pictured is a semi-automatic device that permits highly accurate blood pressure measurement, even by untrained personnel. Developed by Meditron Instrument Corporation, Milford, New Hampshire, it is based in part on NASA technology found in a similar system designed for automatic monitoring of astronauts' blood pressure. Vital-2 is an advancement over the familiar arm cuff, dial and bulb apparatus customarily used for blood pressure checks. In that method, the physician squeezes the bulb to inflate the arm cuff, which restricts the flow of blood through the arteries. As he eases the pressure on the arm, he listens, through a stethoscope, to the sounds of resumed blood flow as the arteries expand and contract. Taking dial readings related to sound changes, he gets the systolic (contracting) and diastolic (expanding) blood pressure measurements. The accuracy of the method depends on the physician's skill in interpreting the sounds. Hospitals sometimes employ a more accurate procedure, but it is "invasive," involving insertion of a catheter in the artery.

Software development for the analysis of heartbeat sounds with LabVIEW in diagnosis of cardiovascular disease.

PubMed

Topal, Taner; Polat, Hüseyin; Güler, Inan

2008-10-01

In this paper, a time-frequency spectral analysis software (Heart Sound Analyzer) for the computer-aided analysis of cardiac sounds has been developed with LabVIEW. Software modules reveal important information for cardiovascular disorders, it can also assist to general physicians to come up with more accurate and reliable diagnosis at early stages. Heart sound analyzer (HSA) software can overcome the deficiency of expert doctors and help them in rural as well as urban clinics and hospitals. HSA has two main blocks: data acquisition and preprocessing, time-frequency spectral analyses. The heart sounds are first acquired using a modified stethoscope which has an electret microphone in it. Then, the signals are analysed using the time-frequency/scale spectral analysis techniques such as STFT, Wigner-Ville distribution and wavelet transforms. HSA modules have been tested with real heart sounds from 35 volunteers and proved to be quite efficient and robust while dealing with a large variety of pathological conditions.

High-temporal-resolution CdTe nuclear stethoscope for cardiac γ-ventriculography: preclinical evaluation

NASA Astrophysics Data System (ADS)

Eclancher, Bernard; Arntz, Y.; Chambron, Jacques; Prat, Vincent; Perret, C.; Karman, Miklos; Pszota, Agnes; Nemeth, Laszlo

1999-10-01

A hand-size probe including 64 elementary 5 X 5 X 2 mm CdTe detectors has been optimized to detect the (gamma) tracer 99Tc in the heart left ventricle. The system, has been developed, not for imaging, allowing acquisitions at 33 Hz to describe the labeled blood volume variations. The (gamma) -counts variations were found accurately proportional to the known volume variations of an artificial ventricle paced at variable rate and systolic volume. Softwares for on line data monitoring and for post-processing have been developed for beat to beat assessment of cardiac performance at rest and during physical exercise. The evaluation of this probe has been performed on 5 subjects in the Nucl Dep of Balatonfured Cardiology Hospital. It appears that the probe needs to be better shielded to work properly in the hot environment of the ventricle, but can provide reliable ventriculography, even under heavy exercise load, although the ventricle volume itself is unknown.

Detecting regional lung properties using audio transfer functions of the respiratory system.

PubMed

Mulligan, K; Adler, A; Goubran, R

2009-01-01

In this study, a novel instrument has been developed for measuring changes in the distribution of lung fluid the respiratory system. The instrument consists of a speaker that inputs a 0-4kHz White Gaussian Noise (WGN) signal into a patient's mouth and an array of 4 electronic stethoscopes, linked via a fully adjustable harness, used to recover signals on the chest surface. The software system for processing the data utilizes the principles of adaptive filtering in order to obtain a transfer function that represents the input-output relationship for the signal as the volume of fluid in the lungs is varied. A chest phantom model was constructed to simulate the behavior of fluid related diseases within the lungs through the injection of varying volumes of water. Tests from the phantom model were compared to healthy subjects. Results show the instrument can obtain similar transfer functions and sound propagation delays between both human and phantom chests.

Value and limitations of auscultation in the management of congenital heart disease.

PubMed

McNamara, D G

1990-02-01

With advances in technology, especially that of ultrasonography, the art and science of auscultation could become relegated to that of an obsolete technique. Physicians in a cardiovascular training program involved in learning modern instrumentation diagnostic techniques often become expert in these areas before they have mastered the use of the stethoscope. Although the technology of ultrasonic examination, cardiac catheterization, and angiocardiography must be learned, the value of auscultation of the heart cannot be ignored. Many highly competent physicians who are responsible for diagnosis and treatment of the pediatric patient, including some pediatric cardiologists, may not be aware that they have not yet become experts at auscultation. The skill of auscultation of the heart must be learned by supervised experience with patients in whom a wide variety of normal and abnormal heart sounds and murmurs can be heard. Once learned, the skill can be maintained only by frequent practice in hearing and evaluating both subtle and obvious sounds emanating from the heart and from the pulmonary and systemic blood vessels.

A French national research project to the creation of an auscultation's school: the ASAP project.

PubMed

Andrès, Emmanuel; Reichert, Sandra; Gass, Raymond; Brandt, Christian

2009-05-01

Auscultation of pulmonary sounds provides valuable clinical information but has been regarded as a tool of low diagnostic value due to the inherent subjectivity in the evaluation of these sounds. This paper describes an ambitious study of in the so-called ASAP project or "Analyse de Sons Auscultatoires et Pathologiques". ASAP is a 3-year-long French collaborative project developed in the context of the News Technologies of Information and Communication. ASAP aims at making evolve the auscultation technics: by 1) the development objective tools for the analyse of auscultation sounds: electronic stethoscopes paired with computing device; 2) the creation of an auscultation sounds' database in order to compare and identify the acoustical and visual signatures of the pathologies; and 3) the capitalisation of these new auscultation techniques around the creation of a teaching unit: "Ecole de l'Auscultation". This auscultation's school will be destined to the initial and continuous formation of the medical attendants.

An ultra-sensitive wearable accelerometer for continuous heart and lung sound monitoring.

PubMed

Hu, Yating; Xu, Yong

2012-01-01

This paper presents a chest-worn accelerometer with high sensitivity for continuous cardio-respiratory sound monitoring. The accelerometer is based on an asymmetrical gapped cantilever which is composed of a bottom mechanical layer and a top piezoelectric layer separated by a gap. This novel structure helps to increase the sensitivity by orders of magnitude compared with conventional cantilever based accelerometers. The prototype with a resonant frequency of 1100Hz and a total weight of 5 gram is designed, constructed and characterized. The size of the prototype sensor is 35mm×18mm×7.8mm (l×w×t). A built-in charge amplifier is used to amplify the output voltage of the sensor. A sensitivity of 86V/g and a noise floor of 40ng/√Hz are obtained. Preliminary tests for recording both cardiac and respiratory signals are carried out on human body and the new sensor exhibits better performance compared with a high-end electronic stethoscope.

Is it Time to Replace Physical Examination with a Hand-Held Ultrasound Device?

PubMed Central

Kaul, Sanjiv

2014-01-01

Attempts at using physical examination (PE) go back centuries, with inspection, palpation, and percussion being the mainstay of this approach until 2 centuries ago when the stethoscope was invented and auscultation became probably the most important element of PE for patients with known or suspected cardiovascular disease (CVD). Despite its several limitations, PE is still used, sometimes as the only means, of evaluating and following patients with CVD. In this paper I shall argue for the substitution of this inaccurate and archaic approach by direct visualization of the heart using a hand-held ultrasound (HHU) device. I am not in any way suggesting the substitution of a comprehensive echocardiographic examination by an expert sonographer/echocardiographer by HHU in patients with significant CVD. Instead, I am arguing for the replacement of PE for evaluation of the heart at the point of care as well as at the bedside, simply because HHU is more accurate and provides more meaningful information. PMID:28465916

Is it Time to Replace Physical Examination with a Hand-Held Ultrasound Device?

PubMed

Kaul, Sanjiv

2014-01-01

Attempts at using physical examination (PE) go back centuries, with inspection, palpation, and percussion being the mainstay of this approach until 2 centuries ago when the stethoscope was invented and auscultation became probably the most important element of PE for patients with known or suspected cardiovascular disease (CVD). Despite its several limitations, PE is still used, sometimes as the only means, of evaluating and following patients with CVD. In this paper I shall argue for the substitution of this inaccurate and archaic approach by direct visualization of the heart using a hand-held ultrasound (HHU) device. I am not in any way suggesting the substitution of a comprehensive echocardiographic examination by an expert sonographer/echocardiographer by HHU in patients with significant CVD. Instead, I am arguing for the replacement of PE for evaluation of the heart at the point of care as well as at the bedside, simply because HHU is more accurate and provides more meaningful information.

Safety and efficacy of misoprostol for induction of labour in a semi-urban hospital setting.

PubMed

Loto, O M; Fadahunsi, A A; Kolade, C O

2004-09-01

Most studies on the use of misoprostol for induction of labour have been carried out in well-endowed hospitals in developed countries with state-of-the-art monitoring equipment. There is need for more studies to be conducted in facilities with limited resources, if more patients are to benefit from the low cost and effectiveness of the drug. Following Ethical Committee approval, 152 women had labour induced in our maternity unit using intravaginal misoprostol. The patients were monitored clinically using the WHO model partograph with digital palpation of uterine contractions and intermittent auscultation of fetal heart with a pinard stethoscope. One hundred and thirty-five (88.8%) of the women had a vaginal delivery, while nine (5.9%) had a caesarean section for various obstetric indications. Eight cases of uterine hyperstimulation were noted but none of uterine rupture. We conclude that misoprostol can be used safely for induction of labour in less endowed hospital settings such as in developing countries, using basic clinical tools for monitoring.

Comparison of infant heart rate assessment by auscultation, ECG and oximetry in the delivery room.

PubMed

Murphy, Madeleine C; De Angelis, Laura; McCarthy, Lisa K; O'Donnell, Colm Patrick Finbarr

2018-05-25

Clinical assessment of an infant's heart rate (HR) in the delivery room (DR) has been reported to be inaccurate. We compared auscultation of the HR using a stethoscope with electrocardiography (ECG) and pulse oximetry (PO) for determining the HR in 92 low-risk newborn infants in the DR. Caregivers auscultated the HR while masked to the HR on the monitor. Auscultation underestimated ECG HR (mean difference (95% CI) by -9 (-15 to -2) beats per minute (bpm)) and PO HR (mean difference (95% CI) by -5 (-12 to 2) bpm). The median (IQR) time to HR by auscultation was 14 (10-18) s. As HR was determined quickly and with reasonable accuracy by auscultation in low-risk newborns, study in high-risk infants is warranted. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Assessment of left ventricular ejection fraction using an ultrasonic stethoscope in critically ill patients

PubMed Central

2012-01-01

Introduction Assessment of cardiac function is key in the management of intensive care unit (ICU) patients and frequently relies on the use of standard transthoracic echocardiography (TTE). A commercially available new generation ultrasound system with two-dimensional imaging capability, which has roughly the size of a mobile phone, is adequately suited to extend the physical examination. The primary endpoint of this study was to evaluate the additional value of this new miniaturized device used as an ultrasonic stethoscope (US) for the determination of left ventricular (LV) systolic function, when compared to conventional clinical assessment by experienced intensivists. The secondary endpoint was to validate the US against TTE for the semi-quantitative assessment of left ventricular ejection fraction (LVEF) in ICU patients. Methods In this single-center prospective descriptive study, LVEF was independently assessed clinically by the attending physician and echocardiographically by two experienced intensivists trained in critical care echocardiography who used the US (size: 135 × 73 × 28 mm; weight: 390 g) and TTE. LVEF was visually estimated semi-quantitatively and classified in one of the following categories: increased (LVEF > 75%), normal (LVEF: 50 to 75%), moderately reduced (LVEF: 30 to 49%), or severely reduced (LVEF < 30%). Biplane LVEF measured using the Simpson's rule on TTE loops by an independent investigator was used as reference. Results A total of 94 consecutive patients were studied (age: 60 ± 17 years; simplified acute physiologic score 2: 41 ± 15), 63 being mechanically ventilated and 36 receiving vasopressors and/or inotropes. Diagnostic concordance between the clinically estimated LVEF and biplane LVEF was poor (Kappa: 0.33; 95% CI: 0.16 to 0.49) and only slightly improved by the knowledge of a previously determined LVEF value (Kappa: 0.44; 95% CI: 0.22 to 0.66). In contrast, the diagnostic agreement was good between visually assessed LVEF using the US and TTE (Kappa: 0.75; CI 95%: 0.63 to 0.87) and between LVEF assessed on-line and biplane LVEF, regardless of the system used (Kappa: 0.75; CI 95%: 0.64 to 0.87 and Kappa: 0.70; CI 95%: 0.59 to 0.82, respectively). Conclusions In ICU patients, the extension of physical examination using an US improves the ability of trained intensivists to determine LVEF at bedside. With trained operators, the semi-quantitative assessment of LVEF using the US is accurate when compared to standard TTE. PMID:22335818

Hemodynamics of the Aortic Jet and Implications for Detection of Aortic Stenosis Murmurs

NASA Astrophysics Data System (ADS)

Zhu, Chi; Seo, Junghee; Bakhshaee, Hani; Mittal, Rajat

2016-11-01

Cardiac auscultation with a stethoscope has served as the primary method for qualitative screening of cardiovascular conditions for over a hundred years. However, a lack of quantitative understanding of the flow mechanism(s) responsible for the generation of the murmurs, as well as the effect of intervening tissue on the propagation of these murmurs has been a significant limiting factor in the advancement of automated cardiac auscultation. In this study, a multiphysics computational modeling approach is used to investigate these issues. Direct numerical simulation (DNS) is used to explore the fluid dynamics of the jets formed at the aortic valve and the pressure fluctuations generated by the interaction of this jet with the aortic wall. Subsequently, structural wave propagation in the tissue is resolved by a high-order, linear viscoelastic wave solver in order to explore the propagation of the murmurs through a tissue-like material. The implications of these results for cardiac auscultation are discussed. The authors would like to acknowledge the financial support from NSF Grants IIS-1344772, CBET-1511200, and computational resource by XSEDE NSF Grant TG-CTS100002.

Healthcare Personnel Attire and Devices as Fomites: A Systematic Review.

PubMed

Haun, Nicholas; Hooper-Lane, Christopher; Safdar, Nasia

2016-11-01

BACKGROUND Transmission of pathogens within the hospital environment remains a hazard for hospitalized patients. Healthcare personnel clothing and devices carried by them may harbor pathogens and contribute to the risk of pathogen transmission. OBJECTIVE To examine bacterial contamination of healthcare personnel attire and commonly used devices. METHODS Systematic review. RESULTS Of 1,175 studies screened, 72 individual studies assessed contamination of a variety of items, including white coats, neckties, stethoscopes, and mobile electronic devices, with varied pathogens including Staphylococcus aureus, including methicillin-resistant S. aureus, gram-negative rods, and enterococci. Contamination rates varied significantly across studies and by device but in general ranged from 0 to 32% for methicillin-resistant S. aureus and gram-negative rods. Enterococcus was a less common contaminant. Few studies explicitly evaluated for the presence of Clostridium difficile. Sampling and microbiologic techniques varied significantly across studies. Four studies evaluated for possible connection between healthcare personnel contaminants and clinical isolates with no unequivocally direct link identified. CONCLUSIONS Further studies to explore the relationship between healthcare personnel attire and devices and clinical infection are needed. Infect Control Hosp Epidemiol 2016;1-7.

Elemental Study on Auscultaiting Diagnosis Support System of Hemodialysis Shunt Stenosis by ANN

NASA Astrophysics Data System (ADS)

Suzuki, Yutaka; Fukasawa, Mizuya; Mori, Takahiro; Sakata, Osamu; Hattori, Asobu; Kato, Takaya

It is desired to detect stenosis at an early stage to use hemodailysis shunt for longer time. Stethoscope auscultation of vascular murmurs is useful noninvasive diagnostic approach, but an experienced expert operator is necessary. Some experts often say that the high-pitch murmurs exist if the shunt becomes stenosed, and some studies report that there are some features detected at high frequency by time-frequency analysis. However, some of the murmurs are difficult to detect, and the final judgment is difficult. This study proposes a new diagnosis support system to screen stenosis by using vascular murmurs. The system is performed using artificial neural networks (ANN) with the analyzed frequency data by maximum entropy method (MEM). The author recorded vascular murmurs both before percutaneous transluminal angioplasty (PTA) and after. Examining the MEM spectral characteristics of the high-pitch stenosis murmurs, three features could be classified, which covered 85 percent of stenosis vascular murmurs. The features were learnt by the ANN, and judged. As a result, a percentage of judging the classified stenosis murmurs was 100%, and that of normal was 86%.

An Auscultaiting Diagnosis Support System for Assessing Hemodialysis Shunt Stenosis by Using Self-organizing Map

NASA Astrophysics Data System (ADS)

Suzuki, Yutaka; Fukasawa, Mizuya; Sakata, Osamu; Kato, Hatsuhiro; Hattori, Asobu; Kato, Takaya

Vascular access for hemodialysis is a lifeline for over 280,000 chronic renal failure patients in Japan. Early detection of stenosis may facilitate long-term use of hemodialysis shunts. Stethoscope auscultation of vascular murmurs has some utility in the assessment of access patency; however, the sensitivity of this diagnostic approach is skill dependent. This study proposes a novel diagnosis support system to detect stenosis by using vascular murmurs. The system is based on a self-organizing map (SOM) and short-time maximum entropy method (STMEM) for data analysis. SOM is an artificial neural network, which is trained using unsupervised learning to produce a feature map that is useful for visualizing the analogous relationship between input data. The author recorded vascular murmurs before and after percutaneous transluminal angioplasty (PTA). The SOM-based classification was consistent with to the classification based on MEM spectral and spectrogram characteristics. The ratio of pre-PTA murmurs in the stenosis category was much higher than the post-PTA murmurs. The results suggest that the proposed method may be an effective tool in the determination of shunt stenosis.

Atomic force microscopy as nano-stethoscope to study living organisms, insects

NASA Astrophysics Data System (ADS)

Sokolov, Igor; Dokukin, Maxim; Guz, Nataliia

2012-02-01

Atomic force microscopy (AFM) is a known method to study various surfaces. Here we report on the use of AFM to study surface oscillations (coming from the work of internal organs) of living organisms, like insects. As an example, ladybird beetles (Hippodamia convergens) measured in different parts of the insect at picometer level. This allows us to record a much broader spectral range of possible surface vibrations (up to several kHz) than the previously studied oscillations due to breathing, heartbeat cycles, coelopulses, etc. (up to 5 -10 Hz). The used here AFM method allows collecting signal from the area as small as ˜100nm2 (0.0001μm2) with an example of noise level of (2±0.2)x10-3 nm r.m.s. at the range of frequencies >50Hz (potentially, up to a MHz). Application of this method to humans is discussed. The method, being a relatively non-invasive technique providing a new type of information, may be useful in developing of what could be called ``nanophysiology.''

Thermal radiation scanning tunnelling microscopy

NASA Astrophysics Data System (ADS)

de Wilde, Yannick; Formanek, Florian; Carminati, Rémi; Gralak, Boris; Lemoine, Paul-Arthur; Joulain, Karl; Mulet, Jean-Philippe; Chen, Yong; Greffet, Jean-Jacques

2006-12-01

In standard near-field scanning optical microscopy (NSOM), a subwavelength probe acts as an optical `stethoscope' to map the near field produced at the sample surface by external illumination. This technique has been applied using visible, infrared, terahertz and gigahertz radiation to illuminate the sample, providing a resolution well beyond the diffraction limit. NSOM is well suited to study surface waves such as surface plasmons or surface-phonon polaritons. Using an aperture NSOM with visible laser illumination, a near-field interference pattern around a corral structure has been observed, whose features were similar to the scanning tunnelling microscope image of the electronic waves in a quantum corral. Here we describe an infrared NSOM that operates without any external illumination: it is a near-field analogue of a night-vision camera, making use of the thermal infrared evanescent fields emitted by the surface, and behaves as an optical scanning tunnelling microscope. We therefore term this instrument a `thermal radiation scanning tunnelling microscope' (TRSTM). We show the first TRSTM images of thermally excited surface plasmons, and demonstrate spatial coherence effects in near-field thermal emission.

The Patient-Surgeon Relationship in the Cyber Era: Communication and Information

PubMed Central

Blake, J. Herman; Schwemmer, Mary Kay; Sade, Robert M.

2012-01-01

Synopsis From Laennec’s invention of the stethoscope in 1816 to the recently introduced Sapien transcatheter aortic valve replacement, the increasing complexity of health care technology has altered the relationship between patients and physicians, usually for the better. Telemedicine, the provision of medical services through electronic media, has dramatically changed how the patient and physician interact and how medical care is delivered. A consistent pattern of increased use of the Internet by patients and their families has been well documented. Patients clearly want more Internet interactions with clinicians in their quest for general information, prescription renewals, and such administrative matters as scheduling appointments. Despite privacy concerns, patients are generally satisfied that their communications and medical records are confidential and accurate. Physicians’ utilization of information technology has increased as the range of electronic devices and modes of communication has expanded. Many studies of physicians’ perceptions of electronic communication with patients have documented recognition of benefits as well as a consistent chorus of concerns about confidentiality, increased workload, inappropriate use, and medicolegal issues. PMID:23084616

[Lung auscultation: an old skill with new interpretation and terminology].

PubMed

Peros-Golubicić, T

1994-01-01

The lung sound auscultation is a part of everyday practice of most physicians. This skill used to be in practice in antique times, but it did not gain any particular attention until the beginning of the 19th century when Laennec systematized his observations, so that the method became generally accepted as the means of examining the patient. Today the stethoscope has almost become the symbol of medical profession, and without it no worthy caricature on behalf of a physician is possible. In this article except short historical review of the lung auscultation, the new technical innovations, including the use of computers which have led to new insights into the characteristics of the lung sounds in health and disease have been shown. Indeed, the technical innovations have insured more accurate measurement of all characteristics of lung sounds, and in connection with this enabled the coining of new terms, especially for adventitious lung sounds. As the whole civilized world has agreed upon the terminology, in the radiance of the above mentioned we are also proposing new terminology for adventitious lung sounds.

[Anesthetic care for fibrobronchoscopy in patients with chronic terminal respiratory insufficiency undergoing evaluation for isolated lung transplantation].

PubMed

Solca, M; Elena, A; Croci, M; Damia, G

1993-01-01

During the first 18 month operation of the isolated lung transplantation program at or Institution, eight patients with terminal chronic respiratory failure underwent fiberoptic bronchoscopy and broncho-alveolar lavage as part of their evaluation for isolated lung transplantation. Four patients had severe obstructive, three restrictive, and one mixed, obstructive and restrictive, disease; all of them were on continuous supplemental oxygen. Procedures were performed under topical anaesthesia, with either light sedation or simple monitored anaesthesia care. Monitoring included non-invasive blood pressure measurement, pulse oximeter and precordial stethoscope. No adverse events were recorded, except in one case, when pulse oximeter reading precipitously dropped below 80%, to a minimum of 68-69%. The procedures was terminated short of its completion, and the patient was briefly assisted with manual bag ventilation on oxygen 100%. Pulse oximeter quickly returned to normal levels (above 90%), and the patient promptly recovered, without complications. The importance of monitored anaesthesia care during fiberoptic bronchoscopy (a usually benign procedure) in critically ill patients is greatly emphasized.

Cuba's Family Doctor-and-Nurse Teams: A Day in the Life.

PubMed

Gorry, Conner

2017-01-01

Nurse Sarait Guarat has Felipe's clinical history out of the file cabinet and on Dr Martha Diaz's desk before he's even through the door. Not that Dr Díaz needs it: Having served 26 years at Consultorio (Family Doctor-and-Nurse Office) #17 on a leafy street in Havana's Vedado neighborhood, she knows each of her patients by name and their health status essentially by heart. After greeting 91-year old Felipe with the customary kiss on the cheek, Dr Díaz gets down to business, asking after his family, checking up on his diabetes and inquiring about the reason for his visit. "He's had an upset stomach and some diarrhea, doctora," his wife says from across the room. "That's not good. Let's find out what's going on," responds Dr Díaz, glancing at Felipe with a smile while donning her stethoscope to listen to his heart. After Felipe is weighed by Sarait, a nurse with 25 years' experience in Cuban primary care, Dr Díaz takes his blood pressure and commends him for his healthy 110/70.

Design of heart rate monitor based on piezoelectric sensor using an Arduino

NASA Astrophysics Data System (ADS)

Setyowati, Veni; Muninggar, Jodelin; Shanti. N. A, Made R. S.

2017-01-01

Reading of result heart rate using an acoustic stethoscope needs a particular skill, quiet environment, and hearing sensitivity. This project had the purpose design of a user-friendly automatic heart rate monitor and especially in a noisy area which to eliminate problems and incorrect reading of result. The liquid crystal display shows a heart rate as a result of measurements. The design of the heart rate monitor has two main parts; the signal recorder that a piezoelectric sensor, a filter, and an amplifier as recorder. The second parts was Arduino microcontroller with reinforced. Besides, three supporting buttons provided as the manual switches, the ‘on’, the ‘start’, and ‘reset’ buttons. The values acquired from the heart rate monitor indicate that those were on the Vernier BPS-BTA value range. The measurement error factor of the heart rate monitor then compared to the Vernier BPS-BTA test device was 3.15%. Besides, the value of statistical independent-test indicates that there is no significant difference (P = 0.971) between the heart rate monitor device and the Vernier BPS-BTA. In conclusion, this device was ready to be used because it has almost the same accuracy with the standart device.

Anesthesia in patients with infectious disease caused by multi-drug resistant bacteria.

PubMed

Einav, Sharon; Wiener-Well, Yonit

2017-06-01

Up to 50% of specific bacterial strains in healthcare admission facilities are multi-drug resistant organisms (MDROs). Involvement of anesthesiologists in management of patients carrying/at risk of carrying MDROs may decrease transmission in the Operating Room (OR). Anesthesiologists, their work area and tools have all been implicated in MDRO outbreaks. Causes include contamination of external ventilation circuits and noncontribution of filters to prevention, inappropriate decontamination procedures for nondisposable equipment (e.g. laryngoscopes, bronchoscopes and stethoscopes) and the anesthesia workplace (e.g. external surfaces of cart and anesthesia machine, telephones and computer keyboards) during OR cleaning and lack of training in sterile drug management. Discussions regarding the management of potential MDRO carriers must include anesthesia providers to optimize infection control interventions as well as the anesthesia method, the location of surgery and recovery and the details of patient transport. Anesthesia staff must learn to identify patients at risk for MDRO infection. Antibiotic prophylaxis, although not evidence based, should adhere to known best practices. Adjuvant therapies (e.g. intranasal Mupirocin and bathing with antiseptics) should be considered. Addition of nonmanual OR cleaning methods such as ultraviolet irradiation or gaseous decontamination is encouraged. Anesthesiologists must undergo formal training in sterile drug preparation and administration.

Epidermal mechano-acoustic sensing electronics for cardiovascular diagnostics and human-machine interfaces.

PubMed

Liu, Yuhao; Norton, James J S; Qazi, Raza; Zou, Zhanan; Ammann, Kaitlyn R; Liu, Hank; Yan, Lingqing; Tran, Phat L; Jang, Kyung-In; Lee, Jung Woo; Zhang, Douglas; Kilian, Kristopher A; Jung, Sung Hee; Bretl, Timothy; Xiao, Jianliang; Slepian, Marvin J; Huang, Yonggang; Jeong, Jae-Woong; Rogers, John A

2016-11-01

Physiological mechano-acoustic signals, often with frequencies and intensities that are beyond those associated with the audible range, provide information of great clinical utility. Stethoscopes and digital accelerometers in conventional packages can capture some relevant data, but neither is suitable for use in a continuous, wearable mode, and both have shortcomings associated with mechanical transduction of signals through the skin. We report a soft, conformal class of device configured specifically for mechano-acoustic recording from the skin, capable of being used on nearly any part of the body, in forms that maximize detectable signals and allow for multimodal operation, such as electrophysiological recording. Experimental and computational studies highlight the key roles of low effective modulus and low areal mass density for effective operation in this type of measurement mode on the skin. Demonstrations involving seismocardiography and heart murmur detection in a series of cardiac patients illustrate utility in advanced clinical diagnostics. Monitoring of pump thrombosis in ventricular assist devices provides an example in characterization of mechanical implants. Speech recognition and human-machine interfaces represent additional demonstrated applications. These and other possibilities suggest broad-ranging uses for soft, skin-integrated digital technologies that can capture human body acoustics.

Automated ultrasonic arterial vibrometry: detection and measurement

NASA Astrophysics Data System (ADS)

Plett, Melani I.; Beach, Kirk W.; Paun, Marla

2000-04-01

Since the invention of the stethoscope, the detection of vibrations and sounds from the body has been a touchstone of diagnosis. However, the method is limited to vibrations whose associated sounds transmit to the skin, with no means to determine the anatomic and physiological source of the vibrations save the cunning of the examiner. Using ultrasound quadrature phase demodulation methods similar to those of ultrasonic color flow imaging, we have developed a system to detect and measure tissue vibrations with amplitude excursions as small as 30 nanometers. The system uses wavelet analysis for sensitive and specific detection, as well as measurement, of short duration vibrations amidst clutter and time-varying, colored noise. Vibration detection rates in ROC curves from simulated data predict > 99.5% detections with < 1% false alarms for signal to noise ratios >= 0.5. Vibrations from in vivo arterial stenoses and punctures have been studied. The results show that vibration durations vary from 10 - 150 ms, frequencies from 100 - 1000 Hz, and amplitudes from 30 nanometers to several microns. By marking the location of vibration sources on ultrasound images, and using color to indicate amplitude, frequency or acoustic intensity, new diagnostic information is provided to aid disorder diagnosis and management.

Field results from Whisper® stethoscope studies.

PubMed

Noffsinger, Tom; Brattain, Kurt; Quakenbush, Greg; Taylor, Garrett

2014-12-01

One area where the feedlot industry has been historically weak is the area of BRD "case definition" or diagnosis. Numerous studies demonstrate a weak correlation between lung lesions at harvest and treatment history. This poor track record is due in part to lack of specific chute side diagnostic tools. To analyze the effectiveness of current diagnostic tools (temperature, manual lung scores, and Whisper® lung scores), two data sets were collected. The first evaluated the correlation between rectal temperature, manual lung scores, and case fatality rate in feedlot cattle pulled for BRD. The second evaluated the relative accuracy of Whisper® scores and rectal temperature. Fever was defined as a rectal temperature of 104.5° F or greater. Manual lung scores better correlated with case fatality rate than fever. When fever and Whisper® scores were compared, a Whisper® score of 1 or less better predicted survival than a temperature of less than 104.5° F. The combination of no fever and Whisper® score of 1 or less best predicted survival. The determination of Whisper® score along with rectal temperature in cattle identified with signs of acute BRD can improve case definition, improve risk assessment, and allow more targeted use of antibiotics.

Transfer function for vital infrasound pressures between the carotid artery and the tympanic membrane.

PubMed

Furihata, Kenji; Yamashita, Masato

2013-02-01

While occupational injury is associated with numerous individual and work-related risk factors, including long working hours and short sleep duration, the complex mechanisms causing such injuries are not yet fully understood. The relationship between the infrasound pressures of the tympanic membrane [ear canal pressure (ECP)], detected using an earplug embedded with a low-frequency microphone, and the carotid artery [carotid artery pressure (CAP)], detected using a stethoscope fitted with the same microphone, can be quantitatively characterized using systems analysis. The transfer functions of 40 normal workers (19 to 57 years old) were characterized, involving the analysis of 446 data points. The ECP waveform exhibits a pulsatile character with a slow respiratory component, which is superimposed on a biphasic recording that is synchronous with the cardiac cycle. The respiratory ECP waveform correlates with the instantaneous heart rate. The results also revealed that various fatigue-related risk factors may affect the mean magnitudes of the measured pressures and the delay transfer functions between CAP and ECP in the study population; these factors include systolic blood pressure, salivary amylase activity, age, sleep duration, postural changes, chronic fatigue, and pulse rate.

A sneak peek into digital innovations and wearable sensors for cardiac monitoring.

PubMed

Michard, Frederic

2017-04-01

Many mobile phone or tablet applications have been designed to control cardiovascular risk factors (obesity, smoking, sedentary lifestyle, diabetes and hypertension) or to optimize treatment adherence. Some have been shown to be useful but the long-term benefits remain to be demonstrated. Digital stethoscopes make easier the interpretation of abnormal heart sounds, and the development of pocket-sized echo machines may quickly and significantly expand the use of ultrasounds. Daily home monitoring of pulmonary artery pressures with wireless implantable sensors has been shown to be associated with a significant decrease in hospital readmissions for heart failure. There are more and more non-invasive, wireless, and wearable sensors designed to monitor heart rate, heart rate variability, respiratory rate, arterial oxygen saturation, and thoracic fluid content. They have the potential to change the way we monitor and treat patients with cardiovascular diseases in the hospital and beyond. Some may have the ability to improve quality of care, decrease the number of medical visits and hospitalization, and ultimately health care costs. Validation and outcome studies are needed to clarify, among the growing number of digital innovations and wearable sensors, which tools have real clinical value.

Neglected evidence in idiopathic pulmonary fibrosis and the importance of early diagnosis and treatment.

PubMed

Cottin, Vincent; Richeldi, Luca

2014-03-01

In idiopathic pulmonary fibrosis (IPF), some facts or concepts based on substantial evidence, whilst implicit for learned subspecialists, have previously been neglected and/or not explicitly formulated or made accessible to a wider audience. IPF is strongly associated with cigarette smoking and is predominantly a disease of ageing. However, its cause(s) remain elusive and, thus, it is one of the most challenging diseases for the development of novel effective and safe therapies. With the approval of pirfenidone for patients with mild-to-moderate IPF, an earlier diagnosis of IPF is a prerequisite for earlier treatment and, potentially, improvement of the long-term clinical outcome of this progressive and ultimately fatal disease. An earlier diagnosis may be achieved in IPF by promoting thin-slice chest high-resolution computed tomography screening of interstitial lung disease as a "by-product" of large-scale lung cancer screening strategies in smokers, but other techniques, which have been neglected in the past, are now available. Lung auscultation and early identification of "velcro" crackles has been proposed as a key component of early diagnosis of IPF. An ongoing study is exploring correlations between lung sounds on auscultation obtained using electronic stethoscopes and high-resolution computed tomography patterns.

[Intraoperative monitoring in artificial respiration of premature and newborn infants. I. Monitoring of respiratory parameters and alveolar ventilation].

PubMed

Lenz, G; Heipertz, W; Leidig, E; Madee, S

1986-06-01

Monitoring of ventilation serves to ensure adequate alveolar ventilation and arterial oxygenation, and to avoid pulmonary damage due to mechanical ventilation. Basic clinical monitoring, i.e., inspection, auscultation (including precordial or oesophageal stethoscope) and monitoring of heart rate and blood pressure, is mandatory. Mechanical ventilation is monitored by ventilation pressures (peak pressure, plateau pressure and endexpiratory pressure), ventilation volumes (measured at the in/expiratory valve of the respirator and by hot-wire anemometry at the tube connector), ventilation rate, and inspiratory oxygen concentration (FiO2). Alveolar ventilation should be continuously and indirectly recorded by capnometry (pECO2) and by measurement of transcutaneous pCO2 (tcpCO2), whereas oxygenation is determined via measurement of transcutaneous pO2 (tcpO2). Invasive monitoring of gas exchange is essential in prolonged or intrathoracic interventions as well as in neonates with cardiopulmonary problems. paCO2 may be estimated by capillary or venous blood gas analysis; arterial blood gas analysis is required for exact determination of paCO2 as well as arteriocutaneous pCO2 (atcDCO2) and arterio-end-expiratory (aEDCO2) gradients.

Single-channel mixed signal blind source separation algorithm based on multiple ICA processing

NASA Astrophysics Data System (ADS)

Cheng, Xiefeng; Li, Ji

2017-01-01

Take separating the fetal heart sound signal from the mixed signal that get from the electronic stethoscope as the research background, the paper puts forward a single-channel mixed signal blind source separation algorithm based on multiple ICA processing. Firstly, according to the empirical mode decomposition (EMD), the single-channel mixed signal get multiple orthogonal signal components which are processed by ICA. The multiple independent signal components are called independent sub component of the mixed signal. Then by combining with the multiple independent sub component into single-channel mixed signal, the single-channel signal is expanded to multipath signals, which turns the under-determined blind source separation problem into a well-posed blind source separation problem. Further, the estimate signal of source signal is get by doing the ICA processing. Finally, if the separation effect is not very ideal, combined with the last time's separation effect to the single-channel mixed signal, and keep doing the ICA processing for more times until the desired estimated signal of source signal is get. The simulation results show that the algorithm has good separation effect for the single-channel mixed physiological signals.

Epidermal mechano-acoustic sensing electronics for cardiovascular diagnostics and human-machine interfaces

PubMed Central

Liu, Yuhao; Norton, James J. S.; Qazi, Raza; Zou, Zhanan; Ammann, Kaitlyn R.; Liu, Hank; Yan, Lingqing; Tran, Phat L.; Jang, Kyung-In; Lee, Jung Woo; Zhang, Douglas; Kilian, Kristopher A.; Jung, Sung Hee; Bretl, Timothy; Xiao, Jianliang; Slepian, Marvin J.; Huang, Yonggang; Jeong, Jae-Woong; Rogers, John A.

2016-01-01

Physiological mechano-acoustic signals, often with frequencies and intensities that are beyond those associated with the audible range, provide information of great clinical utility. Stethoscopes and digital accelerometers in conventional packages can capture some relevant data, but neither is suitable for use in a continuous, wearable mode, and both have shortcomings associated with mechanical transduction of signals through the skin. We report a soft, conformal class of device configured specifically for mechano-acoustic recording from the skin, capable of being used on nearly any part of the body, in forms that maximize detectable signals and allow for multimodal operation, such as electrophysiological recording. Experimental and computational studies highlight the key roles of low effective modulus and low areal mass density for effective operation in this type of measurement mode on the skin. Demonstrations involving seismocardiography and heart murmur detection in a series of cardiac patients illustrate utility in advanced clinical diagnostics. Monitoring of pump thrombosis in ventricular assist devices provides an example in characterization of mechanical implants. Speech recognition and human-machine interfaces represent additional demonstrated applications. These and other possibilities suggest broad-ranging uses for soft, skin-integrated digital technologies that can capture human body acoustics. PMID:28138529

Dual transmission model of the fetal heart tone

NASA Astrophysics Data System (ADS)

Baker, Donald A.; Zuckerwar, Allan J.

2004-05-01

Detection of the fetal heart tone by auscultation is sometimes easy, other times very difficult. In the model proposed here, the level of difficulty depends upon the position of the fetus within the maternal abdomen. If the fetus lies in the classical left/right occiput anterior position (head down, back against the maternal abdominal wall), detection by a sensor or stethoscope on the maternal abdominal surface is easy. In this mode, named here the ``direct contact'' mode, the heartbeat pushes the fetus against the detecting sensor. The motion generates pressure by impact and does not involve acoustic propagation at all. If the fetus lies in a persistent occiput posterior position (spine-to-spine, fetus facing forward), detection is difficult. In this, the ``fluid propagation'' mode, sound generated by the fetal heart and propagating across the amniotic fluid produces extremely weak signals at the maternal surface, typically 30 dB lower than those of the direct contact mode. This reduction in tone level can be compensated by judicious selection of detection frequency band and by exploiting the difference between the background noise levels of the two modes. Experimental clinical results, demonstrating the tones associated with the two respective modes, will be presented.

Fluid Dynamics of the Generation and Transmission of Heart Sounds: (2): Direct Simulation using a Coupled Hemo-Elastodynamic Method

NASA Astrophysics Data System (ADS)

Seo, Jung-Hee; Bakhshaee, Hani; Zhu, Chi; Mittal, Rajat

2015-11-01

Patterns of blood flow associated with abnormal heart conditions generate characteristic sounds that can be measured on the chest surface using a stethoscope. This technique of `cardiac auscultation' has been used effectively for over a hundred years to diagnose heart conditions, but the mechanisms that generate heart sounds, as well as the physics of sound transmission through the thorax, are not well understood. Here we present a new computational method for simulating the physics of heart murmur generation and transmission and use it to simulate the murmurs associated with a modeled aortic stenosis. The flow in the model aorta is simulated by the incompressible Navier-Stokes equations and the three-dimensional elastic wave generation and propagation on the surrounding viscoelastic structure are solved with a high-order finite difference method in the time domain. The simulation results are compared with experimental measurements and show good agreement. The present study confirms that the pressure fluctuations on the vessel wall are the source of these heart murmurs, and both compression and shear waves likely plan an important role in cardiac auscultation. Supported by the NSF Grants IOS-1124804 and IIS-1344772, Computational resource by XSEDE NSF grant TG-CTS100002.

[Application of the computer-based respiratory sound analysis system based on Mel-frequency cepstral coefficient and dynamic time warping in healthy children].

PubMed

Yan, W Y; Li, L; Yang, Y G; Lin, X L; Wu, J Z

2016-08-01

We designed a computer-based respiratory sound analysis system to identify pediatric normal lung sound. To verify the validity of the computer-based respiratory sound analysis system. First we downloaded the standard lung sounds from the network database (website: http: //www.easyauscultation.com/lung-sounds-reference-guide) and recorded 3 samples of abnormal loud sound (rhonchi, wheeze and crackles) from three patients of The Department of Pediatrics, the First Affiliated Hospital of Xiamen University. We regarded such lung sounds as"reference lung sounds". The"test lung sounds"were recorded from 29 children form Kindergarten of Xiamen University. we recorded lung sound by portable electronic stethoscope and valid lung sounds were selected by manual identification. We introduced Mel-frequency cepstral coefficient (MFCC) to extract lung sound features and dynamic time warping (DTW) for signal classification. We had 39 standard lung sounds, recorded 58 test lung sounds. This computer-based respiratory sound analysis system was carried out in 58 lung sound recognition, correct identification of 52 times, error identification 6 times. Accuracy was 89.7%. Based on MFCC and DTW, our computer-based respiratory sound analysis system can effectively identify healthy lung sounds of children (accuracy can reach 89.7%), fully embodies the reliability of the lung sounds analysis system.

A multi-purpose open-source triggering platform for magnetic resonance

NASA Astrophysics Data System (ADS)

Ruytenberg, T.; Webb, A. G.; Beenakker, J. W. M.

2014-10-01

Many MR scans need to be synchronised with external events such as the cardiac or respiratory cycles. For common physiological functions commercial trigger equipment exists, but for more experimental inputs these are not available. This paper describes the design of a multi-purpose open-source trigger platform for MR systems. The heart of the system is an open-source Arduino Due microcontroller. This microcontroller samples an analogue input and digitally processes these data to determine the trigger. The output of the microcontroller is programmed to mimic a physiological signal which is fed into the electrocardiogram (ECG) or pulse oximeter port of MR scanner. The microcontroller is connected to a Bluetooth dongle that allows wireless monitoring and control outside the scanner room. This device can be programmed to generate a trigger based on various types of input. As one example, this paper describes how it can be used as an acoustic cardiac triggering unit. For this, a plastic stethoscope is connected to a microphone which is used as an input for the system. This test setup was used to acquire retrospectively-triggered cardiac scans in ten volunteers. Analysis showed that this platform produces a reliable trigger (>99% triggers are correct) with a small average 8 ms variation between the exact trigger points.

A multi-purpose open-source triggering platform for magnetic resonance.

PubMed

Ruytenberg, T; Webb, A G; Beenakker, J W M

2014-10-01

Many MR scans need to be synchronised with external events such as the cardiac or respiratory cycles. For common physiological functions commercial trigger equipment exists, but for more experimental inputs these are not available. This paper describes the design of a multi-purpose open-source trigger platform for MR systems. The heart of the system is an open-source Arduino Due microcontroller. This microcontroller samples an analogue input and digitally processes these data to determine the trigger. The output of the microcontroller is programmed to mimic a physiological signal which is fed into the electrocardiogram (ECG) or pulse oximeter port of MR scanner. The microcontroller is connected to a Bluetooth dongle that allows wireless monitoring and control outside the scanner room. This device can be programmed to generate a trigger based on various types of input. As one example, this paper describes how it can be used as an acoustic cardiac triggering unit. For this, a plastic stethoscope is connected to a microphone which is used as an input for the system. This test setup was used to acquire retrospectively-triggered cardiac scans in ten volunteers. Analysis showed that this platform produces a reliable trigger (>99% triggers are correct) with a small average 8 ms variation between the exact trigger points. Copyright © 2014 Elsevier Inc. All rights reserved.

Repeatability and Reliability Characterization of Phonocardiograph Systems Using Wavelet and Backpropagation Neural Network

NASA Astrophysics Data System (ADS)

Sumarna; Astono, J.; Purwanto, A.; Agustika, D. K.

2018-04-01

Phonocardiograph (PCG) system consisting of an electronic stethoscope, mic condenser, mic preamp, and the battery has been developed. PCG system is used to detect heart abnormalities. Although PCG is not popular because of many things that affect its performance, in this research we try to reduce the factors that affecting its consistency To find out whether the system is repeatable and reliable the system have to be characterized first. This research aims to see whether the PCG system can provide the same results for measurements of the same patient. Characterization of the system is done by analyzing whether the PCG system can recognize the S1 and S2 part of the same person. From the recording result, S1 and S2 then transformed by using Discrete Wavelet Transform of Haar mother wavelet of level 1 and extracted the feature by using data range of approximation coefficients. The result was analyzed by using pattern recognition system of backpropagation neural network. Partially obtained data used as training data and partly used as test data. From the results of the pattern recognition system, it can be concluded that the system accuracy in recognizing S1 reach 87.5% and S2 only hit 67%.

Verification of intravenous catheter placement by auscultation--a simple, noninvasive technique.

PubMed

Lehavi, Amit; Rudich, Utay; Schechtman, Moshe; Katz, Yeshayahu Shai

2014-01-01

Verification of proper placement of an intravenous catheter may not always be simple. We evaluated the auscultation technique for this purpose. Twenty healthy volunteers were randomized for 18G catheter inserted intravenously either in the right (12) or left arm (8), and subcutaneously in the opposite arm. A standard stethoscope was placed over an area approximately 3 cm proximal to the tip of the catheter in the presumed direction of the vein to grade on a 0-6 scale the murmur heard by rapidly injecting 2 mL of NaCl 0.9% solution. The auscultation was evaluated by a blinded staff anesthesiologist. All 20 intravenous injection were evaluated as flow murmurs, and were graded an average 5.65 (±0.98), whereas all 20 subcutaneous injections were evaluated as either crackles or no sound, and were graded an average 2.00 (±1.38), without negative results. Sensitivity was calculated as 95%. Specificity and Kappa could not be calculated due to an empty false-positive group. Being simple, handy and noninvasive, we recommend to use the auscultation technique for verification of the proper placement of an intravenous catheter when uncertain of its position. Data obtained in our limited sample of healthy subjects need to be confirmed in the clinical setting.

Beyond auscultation: acoustic cardiography in clinical practice.

PubMed

Wen, Yong-Na; Lee, Alex Pui-Wai; Fang, Fang; Jin, Chun-Na; Yu, Cheuk-Man

2014-04-01

Cardiac auscultation by stethoscope is widely used but limited by low sensitivity and accuracy. Phonocardiogram was developed in an attempt to provide quantitative and qualitative information of heart sounds and murmurs by transforming acoustic signal into visual wavelet. Although phonocardiogram provides objective heart sound information and holds diagnostic potentials of different heart problems, its examination procedure is time-consuming and it requires specially trained technicians to operate the device. Acoustic cardiography (AUDICOR, Inovise Medical, Inc., Portland, OR, USA) is a major recent advance in the evolution of cardiac auscultation technology. The technique is more efficient and less operator-dependent. It synchronizes cardiac auscultation with ECG recording and provides a comprehensive assessment of both mechanical and electronic function of the heart. The application of acoustic cardiography is far beyond auscultation only. It generates various parameters which have been proven to correlate with gold standards in heart failure diagnosis and ischemic heart disease detection. Its application can be extended to other diseases, including LV hypertrophy, constrictive pericarditis, sleep apnea and ventricular fibrillation. The newly developed ambulatory acoustic cardiography is potentially used in heart failure follow-up in both home and hospital setting. This review comprehensively summarizes acoustic cardiographic research, including the most recent development. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Breathing synchronized assessment of the chest hemodynamics: application to gamma and MR angiography

NASA Astrophysics Data System (ADS)

Eclancher, Bernard; Demangeat, Jean-Louis; Germain, Philippe; Baruthio, Joseph

2003-05-01

The project was to assess by gamma and MR angiography the bulk variations of chest blood volume related to deep and slow breathing movements. The acquisitions were performed at constant intervals on the widely moving system, without cardiac gating. Two fast enough modalities were used: a gamma-stethoscope working at 30 msec intervals for bulk volumic detection (of 99Tc labelled red cells), and MR imaging at 0.5 sec intervals well depicting displacements but not yet performing true angiography. The third modality yielding quantitative imaging was the scintillation gamma camera, but which required 30 sec signal acquisitions for each image. Frames were acquired at 1 sec intervals for up to 30 breathing cycles, and later sorted with double (inspiration and expiration) synchronization for the reconstruction of an average breathing cycle. Convergent results were obtained from the three angiographic modalities, confirming that the deep breathing movements produced inspiratory increases in bulk blood volume and caudal-median displacement of heart and great vessels, and expiratory decreases in blood volume and cranial-left displacement of heart and great vessels. Deep and slow breathing contributed effectively to thoracic blood pumping. The design of a 64x64 channels collimator has been undertaken to speed up the scintillation camera imaging acquisitions.

Fractal dimension to classify the heart sound recordings with KNN and fuzzy c-mean clustering methods

NASA Astrophysics Data System (ADS)

Juniati, D.; Khotimah, C.; Wardani, D. E. K.; Budayasa, K.

2018-01-01

The heart abnormalities can be detected from heart sound. A heart sound can be heard directly with a stethoscope or indirectly by a phonocardiograph, a machine of the heart sound recording. This paper presents the implementation of fractal dimension theory to make a classification of phonocardiograms into a normal heart sound, a murmur, or an extrasystole. The main algorithm used to calculate the fractal dimension was Higuchi’s Algorithm. There were two steps to make a classification of phonocardiograms, feature extraction, and classification. For feature extraction, we used Discrete Wavelet Transform to decompose the signal of heart sound into several sub-bands depending on the selected level. After the decomposition process, the signal was processed using Fast Fourier Transform (FFT) to determine the spectral frequency. The fractal dimension of the FFT output was calculated using Higuchi Algorithm. The classification of fractal dimension of all phonocardiograms was done with KNN and Fuzzy c-mean clustering methods. Based on the research results, the best accuracy obtained was 86.17%, the feature extraction by DWT decomposition level 3 with the value of kmax 50, using 5-fold cross validation and the number of neighbors was 5 at K-NN algorithm. Meanwhile, for fuzzy c-mean clustering, the accuracy was 78.56%.

Telemedicine Networks of EHAS Foundation in Latin America

PubMed Central

Prieto-Egido, Ignacio; Simó-Reigadas, Javier; Liñán-Benítez, Leopoldo; García-Giganto, Víctor; Martínez-Fernández, Andrés

2014-01-01

Rural areas in developing countries are characterized by lack of resources, low population density, and scarcity of communications infrastructure. These circumstances make it difficult to provide appropriate health-care services. This paper explains research results achieved by Enlace Hispano Americano de Salud – Hispano American Health Link (EHAS) and how they have contributed to improve healthcare in isolated areas of developing countries through the use of information and communication technologies (ICT). As the first step, EHAS always collaborates with public health systems to identify its communication and information needs. Based on the analysis of needs, EHAS does research on appropriate technologies to provide communication in each context and on information systems suited to needs of health personnel. In parallel, EHAS has worked to provide applications that, making use of the communications services installed, could improve the health-care services in these remote areas. In this line, solutions to improve epidemiological surveillance or to provide telemedicine services (like a digital stethoscope or a tele-microscopy system) have been developed. EHAS has also performed several researches trying to ensure the sustainability of their solutions and has summarized them in a Management Framework for Sustainable e-Healthcare Provision. Finally, the effort to spread acquired knowledge has crystallized in a book that details all the technologies and procedures previously mentioned. PMID:25360436

A System for Heart Sounds Classification

PubMed Central

Redlarski, Grzegorz; Gradolewski, Dawid; Palkowski, Aleksander

2014-01-01

The future of quick and efficient disease diagnosis lays in the development of reliable non-invasive methods. As for the cardiac diseases – one of the major causes of death around the globe – a concept of an electronic stethoscope equipped with an automatic heart tone identification system appears to be the best solution. Thanks to the advancement in technology, the quality of phonocardiography signals is no longer an issue. However, appropriate algorithms for auto-diagnosis systems of heart diseases that could be capable of distinguishing most of known pathological states have not been yet developed. The main issue is non-stationary character of phonocardiography signals as well as a wide range of distinguishable pathological heart sounds. In this paper a new heart sound classification technique, which might find use in medical diagnostic systems, is presented. It is shown that by combining Linear Predictive Coding coefficients, used for future extraction, with a classifier built upon combining Support Vector Machine and Modified Cuckoo Search algorithm, an improvement in performance of the diagnostic system, in terms of accuracy, complexity and range of distinguishable heart sounds, can be made. The developed system achieved accuracy above 93% for all considered cases including simultaneous identification of twelve different heart sound classes. The respective system is compared with four different major classification methods, proving its reliability. PMID:25393113

Passive exercise of the lower limbs and trunk alleviates decreased intestinal motility in patients in the intensive care unit after cardiovascular surgery.

PubMed

Morisawa, Tomoyuki; Takahashi, Tetsuya; Sasanuma, Naoki; Mabuchi, Satoshi; Takeda, Kenta; Hori, Naoto; Ohashi, Naotsugu; Ide, Takeshi; Domen, Kazuhisa; Nishi, Shinichi

2017-02-01

[Purpose] The purpose of this study was to clarify the effects of passive exercise of the lower limbs and trunk (PELT) in ICU patients after cardiovascular surgery with decreased bowel motility. [Subjects and Methods] Ten ICU patients with clinically-apparent decreased bowel motility during the period of April to July 2016 were enrolled this study. Bowel sounds (BS) for 5 minutes at rest and 5 minutes after PELT were recorded through an electronic stethoscope. A frequency analysis was performed and the BS before and after PELT were compared. In addition, the percent change in BS before and after PELT was determined, and the relationship between the percent change in BS and individual parameters (invasiveness of surgery, inflammation, nutrition, renal function) was examined. [Results] Average BS (integral value) for 5 minutes before and after PELT were 63.1 ± 41.3 mVsec and 115.0 ± 57.8 mVsec, respectively; therefore, BS was significantly increased by PELT. When compared to patients at rest, a significant increase was found 0-4 minutes after PELT. None of the individual parameters was significantly correlated with the percent change. [Conclusion] PELT can increase the bowel motility of ICU patients with decreased bowel motility.

Computerised Analysis of Telemonitored Respiratory Sounds for Predicting Acute Exacerbations of COPD.

PubMed

Fernandez-Granero, Miguel Angel; Sanchez-Morillo, Daniel; Leon-Jimenez, Antonio

2015-10-23

Chronic obstructive pulmonary disease (COPD) is one of the commonest causes of death in the world and poses a substantial burden on healthcare systems and patients' quality of life. The largest component of the related healthcare costs is attributable to admissions due to acute exacerbation (AECOPD). The evidence that might support the effectiveness of the telemonitoring interventions in COPD is limited partially due to the lack of useful predictors for the early detection of AECOPD. Electronic stethoscopes and computerised analyses of respiratory sounds (CARS) techniques provide an opportunity for substantial improvement in the management of respiratory diseases. This exploratory study aimed to evaluate the feasibility of using: (a) a respiratory sensor embedded in a self-tailored housing for ageing users; (b) a telehealth framework; (c) CARS and (d) machine learning techniques for the remote early detection of the AECOPD. In a 6-month pilot study, 16 patients with COPD were equipped with a home base-station and a sensor to daily record their respiratory sounds. Principal component analysis (PCA) and a support vector machine (SVM) classifier was designed to predict AECOPD. 75.8% exacerbations were early detected with an average of 5 ± 1.9 days in advance at medical attention. The proposed method could provide support to patients, physicians and healthcare systems.

Timely diagnosis of dairy calf respiratory disease using a standardized scoring system.

PubMed

McGuirk, Sheila M; Peek, Simon F

2014-12-01

Respiratory disease of young dairy calves is a significant cause of morbidity, mortality, economic loss, and animal welfare concern but there is no gold standard diagnostic test for antemortem diagnosis. Clinical signs typically used to make a diagnosis of respiratory disease of calves are fever, cough, ocular or nasal discharge, abnormal breathing, and auscultation of abnormal lung sounds. Unfortunately, routine screening of calves for respiratory disease on the farm is rarely performed and until more comprehensive, practical and affordable respiratory disease-screening tools such as accelerometers, pedometers, appetite monitors, feed consumption detection systems, remote temperature recording devices, radiant heat detectors, electronic stethoscopes, and thoracic ultrasound are validated, timely diagnosis of respiratory disease can be facilitated using a standardized scoring system. We have developed a scoring system that attributes severity scores to each of four clinical parameters; rectal temperature, cough, nasal discharge, ocular discharge or ear position. A total respiratory score of five points or higher (provided that at least two abnormal parameters are observed) can be used to distinguish affected from unaffected calves. This can be applied as a screening tool twice-weekly to identify pre-weaned calves with respiratory disease thereby facilitating early detection. Coupled with effective treatment protocols, this scoring system will reduce post-weaning pneumonia, chronic pneumonia, and otitis media.

Crackle analysis for chest auscultation and comparison with high-resolution CT findings.

PubMed

Kawamura, Takeo; Matsumoto, Tsuneo; Tanaka, Nobuyuki; Kido, Shoji; Jiang, Zhongwei; Matsunaga, Naofumi

2003-01-01

The purpose of our study was to clarify the correlation between respiratory sounds and the high-resolution CT (HRCT) findings of lung diseases. Respiratory sounds were recorded using a stethoscope in 41 patients with crackles. All had undergone inspiratory and expiratory CT. Subjects included 18 patients with interstitial pneumonia and 23 without interstitial pneumonia. Two parameters, two-cycle duration (2CD) and initial deflection width (IDW) of the "crackle," were induced by time-expanded waveform analysis. Two radiologists independently assessed 11 HRCT findings. An evaluation was carried out to determine whether there was a significant difference in the two parameters between the presence and absence of each HRCT finding. The two parameters of crackles were significantly shorter in the interstitial pneumonia group than the non-interstitial pneumonia group. Ground-glass opacity, honeycombing, lung volume reduction, traction bronchiectasis, centrilobular nodules, emphysematous change, and attenuation and volume change between inspiratory and expiratory CT were correlated with one or two parameters in all patients, whereas the other three findings were not. Among the interstitial pneumonia group, traction bronchiectasis, emphysematous change, and attenuation and volume change between inspiratory and expiratory CT were significantly correlated with one or two parameters. Abnormal respiratory sounds were correlated with some HRCT findings.

[Respiratory syncytial virus infections in children in general practice].

PubMed

Nielsen, Lisa Monica; Halgrener, Jørgen; Hansen, Bjarne V Lühr

2003-06-30

The aim of the study was to describe the course of respiratory syncytial virus (RSV) infections in children under two years of age seen in general practice. Children under two years of age presenting acute respiratory infection during the registration period on 59 GPs' lists participated in the study. The GPs recorded data on a registration chart and a questionnaire was sent to the parents of the children in question one month after the date of inclusion. The children were tested in general practice for the presence of RSV. The GPs' objective findings and choice of treatment as well as the parents' account of the course of disease were compared in children with and without the presence of RSV. A total of 221 children participated in the study. Fifty-seven children were found RSV positive (25.8%). Among the RSV positive children there were significantly more with wheezing audibly detected with examination by stethoscope than among the RSV negative. The remaining parameters (the GP's objective examination, treatment and course of the disease) were distributed independently of the result of the RSV analysis. The results showed that RSV infections in children under two years in general practice are frequent and that the clinical picture most often is uncomplicated.

Detection of explosive cough events in audio recordings by internal sound analysis.

PubMed

Rocha, B M; Mendes, L; Couceiro, R; Henriques, J; Carvalho, P; Paiva, R P

2017-07-01

We present a new method for the discrimination of explosive cough events, which is based on a combination of spectral content descriptors and pitch-related features. After the removal of near-silent segments, a vector of event boundaries is obtained and a proposed set of 9 features is extracted for each event. Two data sets, recorded using electronic stethoscopes and comprising a total of 46 healthy subjects and 13 patients, were employed to evaluate the method. The proposed feature set is compared to three other sets of descriptors: a baseline, a combination of both sets, and an automatic selection of the best 10 features from both sets. The combined feature set yields good results on the cross-validated database, attaining a sensitivity of 92.3±2.3% and a specificity of 84.7±3.3%. Besides, this feature set seems to generalize well when it is trained on a small data set of patients, with a variety of respiratory and cardiovascular diseases, and tested on a bigger data set of mostly healthy subjects: a sensitivity of 93.4% and a specificity of 83.4% are achieved in those conditions. These results demonstrate that complementing the proposed feature set with a baseline set is a promising approach.

Heated wire humidification circuit attenuates the decrease of core temperature during general anesthesia in patients undergoing arthroscopic hip surgery.

PubMed

Park, Sooyong; Yoon, Seok-Hwa; Youn, Ann Misun; Song, Seung Hyun; Hwang, Ja Gyung

2017-12-01

Intraoperative hypothermia is common in patients undergoing general anesthesia during arthroscopic hip surgery. In the present study, we assessed the effect of heating and humidifying the airway with a heated wire humidification circuit (HHC) to attenuate the decrease of core temperature and prevent hypothermia in patients undergoing arthroscopic hip surgery under general anesthesia. Fifty-six patients scheduled for arthroscopic hip surgery were randomly assigned to either a control group using a breathing circuit connected with a heat and moisture exchanger (HME) (n = 28) or an HHC group using a heated wire humidification circuit (n = 28). The decrease in core temperature was measured from anesthetic induction and every 15 minutes thereafter using an esophageal stethoscope. Decrease in core temperature from anesthetic induction to 120 minutes after induction was lower in the HHC group (-0.60 ± 0.27℃) compared to the control group (-0.86 ± 0.29℃) (P = 0.001). However, there was no statistically significant difference in the incidence of intraoperative hypothermia or the incidence of shivering in the postanesthetic care unit. The use of HHC may be considered as a method to attenuate intraoperative decrease in core temperature during arthroscopic hip surgery performed under general anesthesia and exceeding 2 hours in duration.

Fetal heart rate monitoring device using condenser microphone sensor: Validation and comparison to standard devices.

PubMed

Ahmad, Husna Azyan Binti; El-Badawy, Ismail M; Singh, Om Prakash; Hisham, Rozana Binti; Malarvili, M B

2018-04-27

Fetal heart rate (FHR) monitoring device is highly demanded to assess the fetus health condition in home environments. Conventional standard devices such as ultrasonography and cardiotocography are expensive, bulky and uncomfortable and consequently not suitable for long-term monitoring. Herein, we report a device that can be used to measure fetal heart rate in clinical and home environments. The proposed device measures and displays the FHR on a screen liquid crystal display (LCD). The device consists of hardware that comprises condenser microphone sensor, signal conditioning, microcontroller and LCD, and software that involves the algorithm used for processing the conditioned fetal heart signal prior to FHR display. The device's performance is validated based on analysis of variance (ANOVA) test. FHR data was recorded from 22 pregnant women during the 17th to 37th week of gestation using the developed device and two standard devices; AngelSounds and Electronic Stethoscope. The results show that F-value (1.5) is less than F, (3.1) and p-value (p> 0.05). Accordingly, there is no significant difference between the mean readings of the developed and existing devices. Hence, the developed device can be used for monitoring FHR in clinical and home environments.

Emergency Physicians as Good Samaritans: Survey of Frequency, Locations, Supplies and Medications.

PubMed

Burkholder, Taylor W; King, Renee A

2016-01-01

Little is known about the frequency and locations in which emergency physicians (EPs) are bystanders to an accident or emergency; equally uncertain is which contents of an "emergency kit" may be useful during such events. The aim of this study was to describe the frequency and locations of Good Samaritan acts by EPs and also determine which emergency kit supplies and medications were most commonly used by Good Samaritans. We conducted an electronic survey among a convenience sample of EPs in Colorado. Respondents reported a median frequency of 2.0 Good Samaritan acts per five years of practice, with the most common locations being sports and entertainment events (25%), road traffic accidents (21%), and wilderness settings (19%). Of those who had acted as Good Samaritans, 86% reported that at least one supply would have been useful during the most recent event, and 66% reported at least one medication would have been useful. The most useful supplies were gloves (54%), dressings (34%), and a stethoscope (20%), while the most useful medications were oxygen (19%), intravenous fluids (17%), and epinephrine (14%). The majority of EPs can expect to provide Good Samaritan care during their careers and would be better prepared by carrying a kit with common supplies and medications where they are most likely to use them.

Ocean array alters view of Atlantic conveyor

NASA Astrophysics Data System (ADS)

Kornei, Katherine

2018-02-01

Oceanographers have put a stethoscope on the coursing circulatory system of the Atlantic Ocean, and they have found a skittish pulse that's surprisingly strong in the waters east of Greenland—discoveries that should improve climate models. The powerful currents known as the Atlantic meridional overturning circulation (AMOC) are an engine in Earth's climate. The AMOC's shallower limbs—which include the Gulf Stream—move warm water from the tropics northward, warming Western Europe. In the north, the waters cool and sink, forming deeper limbs that transport the cold water back south—and sequester anthropogenic carbon in the process. Last week, at the American Geophysical Union's Ocean Sciences meeting, scientists presented the first data from an array of instruments moored in the subpolar North Atlantic, a $35 million, seven-nation project known as the Overturning in the Subpolar North Atlantic Program (OSNAP). Since 2004, researchers have gathered data from another array, at 26°N, stretching from Florida to Africa. But OSNAP is the first to monitor the circulation farther north, where a critical aspect of the overturning occurs. The observations reveal unexpected eddies and strong variability in the AMOC currents. They also show that the currents east of Greenland contribute the most to the total AMOC flow. Climate models, on the other hand, have emphasized the currents west of Greenland in the Labrador Sea.

Hand-held computers in healthcare: what software programs are available?

PubMed

Gillingham, Wayne; Holt, Alec; Gillies, John

2002-09-27

The technology sector of healthcare is entering a new evolutionary phase. The medical community has an obligation to the public to provide the safest, most effective healthcare possible. This is more achievable with the use of computer technology at the point of care, and small, portable devices could fulfil this role. A PriceWaterhouse Coopers 2001 survey on information technology in physician practices found that 60% of respondents say that physicians in their organisation use personal digital assistants (PDAs), compared with 26% in the 2000 technology survey. This trend is expected to continue to the point where these devices will have their position on a physician s desk next to the stethoscope. Once this electronic evolution occurs, doctors will be able to practice medicine with greater ease and safety. In our opinion, the new generation of PDA mobile devices will be the tools to enable a transformation of healthcare to a paperless, wireless world. This article focuses on uses of PDAs in healthcare, whether by the registrar, consultant, nurse, student, teacher, patient, medical or surgical director. Current PDA healthcare software is categorised and discussed in the following five groups: 1) reference/text book; 2) calculator; 3) patient management/logbook; 4) personal clinical/study notebook; 5) utility software.

Sequential en-face optical coherence tomography imaging and monitoring of Drosophila Melanogaster larval heart

NASA Astrophysics Data System (ADS)

Bradu, A.; Ma, Lisha; Bloor, J.; Podoleanu, A. GH.

2009-02-01

This article demonstrates two modalities to acquire information on cardiac function in larval Drosophila Melanogaster: in-vivo imaging and heartbeat monitoring. To achieve these goals a dedicated imaging instrument able to provide simultaneous en-face Optical Coherence Tomography (OCT) and Laser Scanning Confocal Microscopy (LSCM) images has been developed. With this dual imaging system, the heart can easily be located and visualised within the specimen and the change of the heart shape in a cardiac cycle monitored. The system can easily be switched to a stethoscopic regime, simply by interrupting the scanning of the light beam across the sample, after selecting the point of interest in the imaging regime. Here we have used targeted gene expression to knockdown the myospheroid (mys) gene in the larval heart using a specific RNAi construct. By knocking down a β integrin subunit encoded by mys we have recorded an enlarged heart chamber in both diastolic and systolic states. Also, the fraction of reduction of the chamber diameter was smaller in the knockdown heart. These phenotypic differences indicate that impaired cardiac contractility occurs in the heart where the integrin gene express level is reduced. As far as we are aware, this is for the first time when it is shown in Drosophila that integrins have a direct relationship to a dilated heart defect, and conseqThis article demonstrates two modalities to acquire information on cardiac function in larval Drosophila Melanogaster: in-vivo imaging and heartbeat monitoring. To achieve these goals a dedicated imaging instrument able to provide simultaneous en-face Optical Coherence Tomography (OCT) and Laser Scanning Confocal Microscopy (LSCM) images has been developed. With this dual imaging system, the heart can easily be located and visualised within the specimen and the change of the heart shape in a cardiac cycle monitored. The system can easily be switched to a stethoscopic regime, simply by interrupting the scanning of the light beam across the sample, after selecting the point of interest in the imaging regime. Here we have used targeted gene expression to knockdown the myospheroid (mys) gene in the larval heart using a specific RNAi construct. By knocking down a β integrin subunit encoded by mys we have recorded an enlarged heart chamber in both diastolic and systolic states. Also, the fraction of reduction of the chamber diameter was smaller in the knockdown heart. These phenotypic differences indicate that impaired cardiac contractility occurs in the heart where the integrin gene express level is reduced. As far as we are aware, this is for the first time when it is shown in Drosophila that integrins have a direct relationship to a dilated heart defect, and consequently we demonstrate the utility of Drosophila as model for the study of vertebrate heart disease. By monitoring the heartbeat we also demonstrated a reduction of the heart rate in Tropomyosin mutant compared to the wild type larva.uently we demonstrate the utility of Drosophila as model for the study of vertebrate heart disease. By monitoring the heartbeat we also demonstrated a reduction of the heart rate in Tropomyosin mutant compared to the wild type larva.

Heart Rate Assessment Immediately after Birth.

PubMed

Phillipos, Emily; Solevåg, Anne Lee; Pichler, Gerhard; Aziz, Khalid; van Os, Sylvia; O'Reilly, Megan; Cheung, Po-Yin; Schmölzer, Georg M

2016-01-01

Heart rate assessment immediately after birth in newborn infants is critical to the correct guidance of resuscitation efforts. There are disagreements as to the best method to measure heart rate. The aim of this study was to assess different methods of heart rate assessment in newborn infants at birth to determine the fastest and most accurate method. PubMed, EMBASE and Google Scholar were systematically searched using the following terms: 'infant', 'heart rate', 'monitoring', 'delivery room', 'resuscitation', 'stethoscope', 'auscultation', 'palpation', 'pulse oximetry', 'electrocardiogram', 'Doppler ultrasound', 'photoplethysmography' and 'wearable sensors'. Eighteen studies were identified that described various methods of heart rate assessment in newborn infants immediately after birth. Studies examining auscultation, palpation, pulse oximetry, electrocardiography and Doppler ultrasound as ways to measure heart rate were included. Heart rate measurements by pulse oximetry are superior to auscultation and palpation, but there is contradictory evidence about its accuracy depending on whether the sensor is connected to the infant or the oximeter first. Several studies indicate that electrocardiogram provides a reliable heart rate faster than pulse oximetry. Doppler ultrasound shows potential for clinical use, however future evidence is needed to support this conclusion. Heart rate assessment is important and there are many measurement methods. The accuracy of routinely applied methods varies, with palpation and auscultation being the least accurate and electrocardiogram being the most accurate. More research is needed on Doppler ultrasound before its clinical use. © 2015 S. Karger AG, Basel.

Who should swing the stethoscope? An audit of baseline physical examination and blood monitoring on new patients accepted by an early intervention in psychosis team.

PubMed

Crabb, Jim; McAllister, Mark; Blair, Alison

2009-11-01

It has been established that patients with severe mental illness are at increased risk of physical illness and that physical health screening should be performed when an individual experiences a first episode of psychosis. The aim of the audit was to examine how physical health screening was achieved in the real world of an early intervention in psychosis (EIP) service in Scotland. Of particular interest was considering if primary or secondary care were more effective in providing specific physical health assessment for those presenting to the service. A case note audit was performed. The audit shows that physical examination and blood tests were being completed in the majority of service users under the care of the Esteem service. However, an unacceptably high number were not undergoing sufficient initial screening for metabolic syndrome or having baseline monitoring prior to commencing antipsychotic medication. Our results suggest that relying on primary care to provide physical health screening was not an effective approach in a population experiencing first-episode psychosis. Having a psychiatrist motivated to perform physical health screening within the EIP team may help to improve the uptake of physical health screening. Strategies to improve physical health screening in EIP services are discussed. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Asia Pty Ltd.

Emergency Physicians as Good Samaritans: Survey of Frequency, Locations, Supplies and Medications

PubMed Central

Burkholder, Taylor W.; King, Renee A.

2016-01-01

Introduction Little is known about the frequency and locations in which emergency physicians (EPs) are bystanders to an accident or emergency; equally uncertain is which contents of an “emergency kit” may be useful during such events. The aim of this study was to describe the frequency and locations of Good Samaritan acts by EPs and also determine which emergency kit supplies and medications were most commonly used by Good Samaritans. Methods We conducted an electronic survey among a convenience sample of EPs in Colorado. Results Respondents reported a median frequency of 2.0 Good Samaritan acts per five years of practice, with the most common locations being sports and entertainment events (25%), road traffic accidents (21%), and wilderness settings (19%). Of those who had acted as Good Samaritans, 86% reported that at least one supply would have been useful during the most recent event, and 66% reported at least one medication would have been useful. The most useful supplies were gloves (54%), dressings (34%), and a stethoscope (20%), while the most useful medications were oxygen (19%), intravenous fluids (17%), and epinephrine (14%). Conclusion The majority of EPs can expect to provide Good Samaritan care during their careers and would be better prepared by carrying a kit with common supplies and medications where they are most likely to use them. PMID:26823924

Heated wire humidification circuit attenuates the decrease of core temperature during general anesthesia in patients undergoing arthroscopic hip surgery

PubMed Central

Park, Sooyong; Song, Seung Hyun; Hwang, Ja Gyung

2017-01-01

Background Intraoperative hypothermia is common in patients undergoing general anesthesia during arthroscopic hip surgery. In the present study, we assessed the effect of heating and humidifying the airway with a heated wire humidification circuit (HHC) to attenuate the decrease of core temperature and prevent hypothermia in patients undergoing arthroscopic hip surgery under general anesthesia. Methods Fifty-six patients scheduled for arthroscopic hip surgery were randomly assigned to either a control group using a breathing circuit connected with a heat and moisture exchanger (HME) (n = 28) or an HHC group using a heated wire humidification circuit (n = 28). The decrease in core temperature was measured from anesthetic induction and every 15 minutes thereafter using an esophageal stethoscope. Results Decrease in core temperature from anesthetic induction to 120 minutes after induction was lower in the HHC group (–0.60 ± 0.27℃) compared to the control group (–0.86 ± 0.29℃) (P = 0.001). However, there was no statistically significant difference in the incidence of intraoperative hypothermia or the incidence of shivering in the postanesthetic care unit. Conclusions The use of HHC may be considered as a method to attenuate intraoperative decrease in core temperature during arthroscopic hip surgery performed under general anesthesia and exceeding 2 hours in duration. PMID:29225745

Cervical auscultation as an adjunct to the clinical swallow examination: a comparison with fibre-optic endoscopic evaluation of swallowing.

PubMed

Bergström, Liza; Svensson, Per; Hartelius, Lena

2014-10-01

This prospective, single-blinded study investigated the validity and reliability of cervical auscultation (CA) under two conditions; (1) CA-only, using isolated swallow-sound clips, and (2) CSE + CA, using extra clinical swallow examination (CSE) information such as patient case history, oromotor assessment, and the same swallow-sound clips as condition one. The two CA conditions were compared against a fibre-optic endoscopic evaluation of swallowing (FEES) reference test. Each CA condition consisted of 18 swallows samples compiled from 12 adult patients consecutively referred to the FEES clinic. Patients' swallow sounds were simultaneously recorded during FEES via a Littmann E3200 electronic stethoscope. These 18 swallow samples were sent to 13 experienced dysphagia clinicians recruited from the UK and Australia who were blinded to the FEES results. Samples were rated in terms of (1) if dysphagic, (2) if the patient was safe on consistency trialled, and (3) dysphagia severity. Sensitivity measures ranged from 83-95%, specificity measures from 50-92% across the conditions. Intra-rater agreement ranged from 69-97% total agreement. Inter-rater reliability for dysphagia severity showed substantial agreement (rs = 0.68 and 0.74). Results show good rater reliability for CA-trained speech-language pathologists. Sensitivity and specificity for both CA conditions in this study are comparable to and often better than other well-established CSE components.

Digital auscultation of the uterine artery: a measure of uteroplacental perfusion.

PubMed

Riknagel, Diana; Dinesen, Birthe; Zimmermann, Henrik; Farlie, Richard; Schmidt, Samuel; Toft, Egon; Struijk, Johannes Jan

2016-07-01

This observational study investigated digital auscultation for the purpose of assessing the clinical feasibility of monitoring vascular sounds in pregnancy. The study was performed at the Regional Hospital Viborg, Denmark, and included 29 pregnant women, 10 non-pregnant women and 10 male participants. Digital auscultation was performed with an electronic stethoscope bilaterally near the uterine arteries and correlated to the clinical diagnosis of preeclampsia (PE), intrauterine growth restriction (IUGR) or normal pregnancy in the group of pregnant participants. In the group of non-pregnant participants, digital auscultation was performed as control measurements in the same anatomical positions. The auscultations displayed pulse waveforms comprising systolic and diastolic periods in 20 of the 29 pregnant participants. However, in the non-pregnant and male participants, the pulse waveforms were absent. The pulsatile patterns are thus likely to originate from the arteries in relation to the pregnant uterus. In the participants displaying pulse waveforms, the presence of a dicrotic notch appeared with a sensitivity of 89% and a specificity of 100% in the discrimination of normal pregnancies (n  =  11) from pregnancies with PE or IUGR (n  =  9), (p  <  0.001). This preliminary study shows the potential of identifying vascular complications during pregnancy such as preeclampsia and intrauterine growth restriction. The morphology of the derived pulse contour should be investigated and could be further developed to identify pathophysiology.

A portable cadmium telluride multidetector probe for cardiac function monitoring

NASA Astrophysics Data System (ADS)

Arntz, Y.; Chambron, J.; Dumitresco, B.; Eclancher, B.; Prat, V.

1999-06-01

A new nuclear stethoscope based on a matrix of small CdTe semiconductor detectors has been developed for studying the cardiac performance by gamma ventriculography at the equilibrium, in rest and stress conditions, in the early and recovery phases of the coronary disease and to follow the long-term therapy. The light-weight probe consists of an array of 64 detectors 5×5×2 mm grouped in 16 independent units in a lead shielded aluminum box including 16 preamplifiers. The probe is connected to an electronic box containing DC power supply, 16 channel amplifiers, discriminators and counters, two analog-triggering ECG channels, and interface to a PC. The left ventricle activity is, preferentially, detected by using a low-resolution matching convergent collimator. A physical evaluation of the probe has been performed, both with static tests and dynamically with a hydraulic home-built model of beating heart ventricle paced by a rhythm simulator. The sum of the 16 detectors activity provided a radiocardiogram (RCG) which well depicted the filling and ejection of the cardiac beats, allowing to compare the clinically relevant parameters of the cardiac performance, proportional variables of the stroke volume (SV), ejection fraction (EF) and ventricular flow-rate with the known absolute values programmed on the model. The portable system is now in operation for clinical assessment of cardiac patients.

A Signal Processing Module for the Analysis of Heart Sounds and Heart Murmurs

NASA Astrophysics Data System (ADS)

Javed, Faizan; Venkatachalam, P. A.; H, Ahmad Fadzil M.

2006-04-01

In this paper a Signal Processing Module (SPM) for the computer-aided analysis of heart sounds has been developed. The module reveals important information of cardiovascular disorders and can assist general physician to come up with more accurate and reliable diagnosis at early stages. It can overcome the deficiency of expert doctors in rural as well as urban clinics and hospitals. The module has five main blocks: Data Acquisition & Pre-processing, Segmentation, Feature Extraction, Murmur Detection and Murmur Classification. The heart sounds are first acquired using an electronic stethoscope which has the capability of transferring these signals to the near by workstation using wireless media. Then the signals are segmented into individual cycles as well as individual components using the spectral analysis of heart without using any reference signal like ECG. Then the features are extracted from the individual components using Spectrogram and are used as an input to a MLP (Multiple Layer Perceptron) Neural Network that is trained to detect the presence of heart murmurs. Once the murmur is detected they are classified into seven classes depending on their timing within the cardiac cycle using Smoothed Pseudo Wigner-Ville distribution. The module has been tested with real heart sounds from 40 patients and has proved to be quite efficient and robust while dealing with a large variety of pathological conditions.

Synthesis of vibroarthrographic signals in knee osteoarthritis diagnosis training.

PubMed

Shieh, Chin-Shiuh; Tseng, Chin-Dar; Chang, Li-Yun; Lin, Wei-Chun; Wu, Li-Fu; Wang, Hung-Yu; Chao, Pei-Ju; Chiu, Chien-Liang; Lee, Tsair-Fwu

2016-07-19

Vibroarthrographic (VAG) signals are used as useful indicators of knee osteoarthritis (OA) status. The objective was to build a template database of knee crepitus sounds. Internships can practice in the template database to shorten the time of training for diagnosis of OA. A knee sound signal was obtained using an innovative stethoscope device with a goniometer. Each knee sound signal was recorded with a Kellgren-Lawrence (KL) grade. The sound signal was segmented according to the goniometer data. The signal was Fourier transformed on the correlated frequency segment. An inverse Fourier transform was performed to obtain the time-domain signal. Haar wavelet transform was then done. The median and mean of the wavelet coefficients were chosen to inverse transform the synthesized signal in each KL category. The quality of the synthesized signal was assessed by a clinician. The sample signals were evaluated using different algorithms (median and mean). The accuracy rate of the median coefficient algorithm (93 %) was better than the mean coefficient algorithm (88 %) for cross-validation by a clinician using synthesis of VAG. The artificial signal we synthesized has the potential to build a learning system for medical students, internships and para-medical personnel for the diagnosis of OA. Therefore, our method provides a feasible way to evaluate crepitus sounds that may assist in the diagnosis of knee OA.

Theoretical and practical knowledge of Nursing professionals on indirect blood pressure measurement at a coronary care unit

PubMed Central

Machado, Juliana Pereira; Veiga, Eugenia Velludo; Ferreira, Paulo Alexandre Camargo; Martins, José Carlos Amado; Daniel, Ana Carolina Queiroz Godoy; Oliveira, Amanda dos Santos; da Silva, Patrícia Costa dos Santos

2014-01-01

Objective To determine and to analyze the theoretical and practical knowledge of Nursing professionals on indirect blood pressure measurement. Methods This cross-sectional study included 31 professionals of a coronary care unit (86% of the Nursing staff in the unit). Of these, 38.7% of professionals were nurses and 61.3% nurse technicians. A validated questionnaire was used to theoretical evaluation and for practice assessment the auscultatory technique was applied in a simulation environment, under a non-participant observation. Results To the theoretical knowledge of the stages of preparation of patient and environment, 12.9% mentioned 5-minute of rest, 48.4% checked calibration, and 29.0% chose adequate cuff width. A total of 64.5% of professionals avoided rounding values, and 22.6% mentioned the 6-month deadline period for the equipment calibration. On average, in practice assessment, 65% of the steps were followed. Lacks in knowledge were primary concerning lack of checking the device calibration and stethoscope, measurement of arm circumference to choose the cuff size, and the record of arm used in blood pressure measurement. Conclusion Knowledge was poor and had disparities between theory and practice with evidence of steps taken without proper awareness and lack of consideration of important knowledge during implementation of blood pressure measurement. Educational and operational interventions should be applied systematically with institutional involvement to ensure safe care with reliable values. PMID:25295455

The history of thoracic surgical instruments and instrumentation.

PubMed

Hagopian, E J; Mann, C; Galibert, L A; Steichen, F M

2000-02-01

Thoracic surgical practice has evolved from the innovations of its pioneers. Beginning with the stethoscope discovered by Laënnec with his system of auscultation, to the tools we use in the dissection and control of the hilum of the lung for resection, our practice of thoracic surgery has been entwined with the development of instruments and instrumentation. The development of strategies to prevent death from the open pneumothorax began with manual control of the mediastinum and progressed through differential pressure to, finally, the technique of intubation and the methods of positive-pressure and insufflation anesthesia. The instruments we place in our hands are not enough to define our art. Entry into the chest would not be possible without the use of rib retractors, rib shears, and even periosteal elevators. Finally, to the present day of minimally invasive techniques and the application of thoracoscopy for therapeutic purposes, we find the efforts of our predecessors well developed. For the progression from the fear of the open pneumothorax to the present-day state of the ease of thoracotomy for lung resection we are indebted to those who gave so much of their time and, for some, their lives to death from tuberculosis, to allow the advancement of our practice of surgery. These great people should be remembered not only for their acceptance of novel ideas but also, more importantly, for their lack of fear of testing them.

Classification of voluntary coughs applied to the screening of respiratory disease.

PubMed

Infante, Christian; Chamberlain, Daniel B; Kodgule, Rahul; Fletcher, Richard Ribon

2017-07-01

Pulmonary and respiratory diseases (e.g. asthma, COPD, allergies, pneumonia, tuberculosis, etc.) represent a large proportion of the global disease burden, mortality, and disability. In this context of creating automated diagnostic tools, we explore how the analysis of voluntary cough sounds may be used to screen for pulmonary disease. As a clinical study, voluntary coughs were recorded using a custom mobile phone stethoscope from 54 patients, of which 7 had COPD, 15 had asthma, 11 had allergic rhinitis, 17 had both asthma and allergic rhinitis, and four had both COPD and allergic rhinitis. Data were also collected from 33 healthy subjects. These patients also received full auscultation at 11 sites, given a clinical questionnaire, and underwent full pulmonary function testing (spirometer, body plethysmograph, DLCO) which culminated in a diagnosis provided by an experienced pulmonologist. From machine learning analysis of these data, we show that it is possible to achieve good classification of cough sounds in terms of Wet vs Dry, yielding an ROC curve with AUC of 0.94, and show that voluntary coughs can serve as an effective test for determining Healthy vs Unhealthy (sensitivity=35.7% specificity=100%). We also show that the use of cough sounds can enhance the performance of other diagnostic tools such as a patient questionnaire and peak flow meter; however voluntary coughs alone provide relatively little value in determining specific disease diagnosis.

Validation of automatic wheeze detection in patients with obstructed airways and in healthy subjects.

PubMed

Guntupalli, Kalpalatha K; Alapat, Philip M; Bandi, Venkata D; Kushnir, Igal

2008-12-01

Computerized lung-sound analysis is a sensitive and quantitative method to identify wheezing by its typical pattern on spectral analysis. We evaluated the accuracy of the VRI, a multi-sensor, computer-based device with an automated technique of wheeze detection. The method was validated in 100 sound files from seven subjects with asthma or chronic obstructive pulmonary disease and seven healthy subjects by comparison of auscultation findings, examination of audio files, and computer detection of wheezes. Three blinded physicians identified 40 sound files with wheezes and 60 sound files without wheezes. Sensitivity and specificity were 83% and 85%, respectively. Negative predictive value and positive predictive value were 89% and 79%, respectively. Overall inter-rater agreement was 84%. False positive cases were found to contain sounds that simulate wheezes, such as background noises with high frequencies or strong noises from the throat that could be heard and identified without a stethoscope. The present findings demonstrate that the wheeze detection algorithm has good accuracy, sensitivity, specificity, negative predictive value and positive predictive value for wheeze detection in regional analyses with a single sensor and multiple sensors. Results are similar to those reported in the literature. The device is user-friendly, requires minimal patient effort, and, distinct from other devices, it provides a dynamic image of breath sound distribution with wheeze detection output in less than 1 minute.

Ambulance vehicles as a source of multidrug-resistant infections: a multicenter study in Assiut City, Egypt

PubMed Central

2018-01-01

Background Ambulances may represent a potential source of infection to patients, patients’ relatives, and paramedical staffs. In this study, we analyzed the extent of bacterial contamination in ambulance vehicles and measured the degree of antimicrobial resistance among isolated pathogens. Materials and methods Twenty-five vehicles were included and 16 sampling points were swabbed in each vehicle. Then the swabs were immediately transferred to the laboratory to identify bacterial contaminants utilizing standard microbiological procedures and API® systems. Antibiotic susceptibility testing and screening for methicillin-resistant staphylococci and extended spectrum β-lactamases (ESBLs)-producing Gram-negative rods were carried out. Results A total of 400 samples were collected, 589 bacteria were isolated and 286 (48.6%) of the isolates were potentially pathogenic. The highest contamination rate with pathogenic bacteria was detected in suction devices (75.8%) and stethoscopes (67.7%). Staphylococci were the most frequently detected microorganisms (n=184) followed by Klebsiella spp. (49), Escherichia coli (40), Citrobacter spp. (7), and Proteus spp. (6). Staphylococci were mostly sensitive to vancomycin, whereas Gram-negative bacteria were sensitive to imipenem. Overall, 46.1% of Staphylococcus aureus were methicillin resistant, whereas 20.4% of the coagulase-negative staphylococci were methicillin resistant. Moreover, 36.7% of Klebsiella spp. and 27.5% of E. coli were ESBL producers. Conclusion Our study provides evidence that ambulances represent a source of prehospital multidrug-resistant infections. PMID:29731647

Chest tube stripping in pediatric oncology patients: an experimental study.

PubMed

Oakes, L L; Hinds, P; Rao, B; Bozeman, P; Taylor, B; Stokes, D; Fairclough, D

1993-07-01

Stripping of chest tubes to promote drainage of the thorax of postthoracotomy patients has been routine practice, based on tradition. Recent published findings indicate that significant negative pressures are generated in the tube during stripping that could cause pain, bleeding and possible damage to the patient's lung tissue. To determine whether pediatric oncology patients whose chest tubes were not stripped would differ in frequency of pain, fever or lung complications from patients who underwent routine tube stripping. Data were collected at multiple points during the first 72-hour postoperative period from 16 patients assigned to the stripped or unstripped groups. Pain was measured by the Faces Pain Scale and the Visual Analogue Scale; temperature, by electronic thermometer; and lung complications, by stethoscope and radiographs. Both groups, which were comparable for age, primary diagnosis and prior history of lung problems, received identical supportive nursing and medical care, with the physicians blind to group assignment. The two groups did not differ significantly in frequency of pain, incidence of fever, breath sounds or radiographic findings across measurement points. A strong correlation was found between the pain scores using the two instruments. Patients whose tubes were not stripped did not have an increased risk of infection or lung complications. Study findings indicated that stripping did not increase the frequency of pain. Stripping of chest tubes as a routine postoperative measure is questioned.

Detection of bronchial breathing caused by pneumonia.

PubMed

Gross, V; Fachinger, P; Penzel, Th; Koehler, U; von Wichert, P; Vogelmeier, C

2002-06-01

The classic auscultation with stethoscope is the established clinical method for the detection of lung diseases. The interpretation of the sounds depends on the experience of the investigating physician. Therefore, a new computer-based method has been developed to classify breath sounds from digital lung sound recordings. Lung sounds of 11 patients with one-sided pneumonia and bronchial breathing were recorded on both the pneumonia side and on contralateral healthy side simultaneously using two microphones. The spectral power for the 300-600 Hz frequency band was computed for four respiratory cycles and normalized. For each breath, the ratio R between the time-segments (duration = 0.1 s) with the highest inspiratory and highest expiratory flow was calculated and averaged. We found significant differences in R between the pneumonia side (R = 1.4 +/- 1.3) and the healthy side (R = 0.5 +/- 0.5; p = 0.003 Wilcoxon-test) of lung. In 218 healthy volunteers we found R = 0.3 +/- 0.2 as a reference-value. The differences of ratio R (delta R) between the pneumonia side and the healthy side (delta R = 1.0 +/- 0.9) were significantly higher compared to follow-up studies after recovery (delta R = 0.0 +/- 0.1, p = 0.005 Wilcoxon-test). The computer based detection of bronchial breathing can be considered useful as part of a quantitative monitoring of patients at risk to develop pneumonia.

Intrapartum fetal heart rate monitoring in a combined low- and high-risk population: a controlled clinical trial.

PubMed

Neldam, S; Osler, M; Hansen, P K; Nim, J; Smith, S F; Hertel, J

1986-10-01

In a prospective clinical randomized investigation 487 women had the condition of the fetus during labour supervised by means of stethoscope (AUS), while 482 women went through labour under surveillance of electronic fetal monitoring, cardiotocography (EFM). 349 women refused to participate in the investigation (NAI) and had delivery conducted according to the normal procedures of the department (70% AUS, 30% EFM). Significantly more pathological fetal heart rate patterns (FHR) were found in the EFM group compared to the AUS group in both the first and the second stage of labour. As a result significantly more vacuum extractions were performed in the EFM group than in the AUS group, while no statistical difference was found between the groups in the incidence of acute cesarean sections carried out for asphyxia. One case of intrapartum death occurred in the AUS group. No differences were found in Apgar scores after 1 and 5 min or in neonatal morbidity at examination on the 2nd and 5th days after delivery. A tendency towards more biochemically compromised children was found in the AUS group. The specificity for both methods was found to be acceptably high (80%), while the predictive value for both methods was low (50%). More research is therefore urgently needed to evaluate supplementary investigations and parameters for the evaluation of the intrapartum fetal condition.

Mobile Phonocardiogram Diagnosis in Newborns Using Support Vector Machine

PubMed Central

Amiri, Amir Mohammad; Abtahi, Mohammadreza; Constant, Nick; Mankodiya, Kunal

2017-01-01

Phonocardiogram (PCG) monitoring on newborns is one of the most important and challenging tasks in the heart assessment in the early ages of life. In this paper, we present a novel approach for cardiac monitoring applied in PCG data. This basic system coupled with denoising, segmentation, cardiac cycle selection and classification of heart sound can be used widely for a large number of the data. This paper describes the problems and additional advantages of the PCG method including the possibility of recording heart sound at home, removing unwanted noises and data reduction on a mobile device, and an intelligent system to diagnose heart diseases on the cloud server. A wide range of physiological features from various analysis domains, including modeling, time/frequency domain analysis, an algorithm, etc., is proposed in order to extract features which will be considered as inputs for the classifier. In order to record the PCG data set from multiple subjects over one year, an electronic stethoscope was used for collecting data that was connected to a mobile device. In this study, we used different types of classifiers in order to distinguish between healthy and pathological heart sounds, and a comparison on the performances revealed that support vector machine (SVM) provides 92.2% accuracy and AUC = 0.98 in a time of 1.14 seconds for training, on a dataset of 116 samples. PMID:28335471

Dysphagia Screening: Contributions of Cervical Auscultation Signals and Modern Signal-Processing Techniques

PubMed Central

Dudik, Joshua M.; Coyle, James L.

2015-01-01

Cervical auscultation is the recording of sounds and vibrations caused by the human body from the throat during swallowing. While traditionally done by a trained clinician with a stethoscope, much work has been put towards developing more sensitive and clinically useful methods to characterize the data obtained with this technique. The eventual goal of the field is to improve the effectiveness of screening algorithms designed to predict the risk that swallowing disorders pose to individual patients’ health and safety. This paper provides an overview of these signal processing techniques and summarizes recent advances made with digital transducers in hopes of organizing the highly varied research on cervical auscultation. It investigates where on the body these transducers are placed in order to record a signal as well as the collection of analog and digital filtering techniques used to further improve the signal quality. It also presents the wide array of methods and features used to characterize these signals, ranging from simply counting the number of swallows that occur over a period of time to calculating various descriptive features in the time, frequency, and phase space domains. Finally, this paper presents the algorithms that have been used to classify this data into ‘normal’ and ‘abnormal’ categories. Both linear as well as non-linear techniques are presented in this regard. PMID:26213659

Noise/spike detection in phonocardiogram signal as a cyclic random process with non-stationary period interval.

PubMed

Naseri, H; Homaeinezhad, M R; Pourkhajeh, H

2013-09-01

The major aim of this study is to describe a unified procedure for detecting noisy segments and spikes in transduced signals with a cyclic but non-stationary periodic nature. According to this procedure, the cycles of the signal (onset and offset locations) are detected. Then, the cycles are clustered into a finite number of groups based on appropriate geometrical- and frequency-based time series. Next, the median template of each time series of each cluster is calculated. Afterwards, a correlation-based technique is devised for making a comparison between a test cycle feature and the associated time series of each cluster. Finally, by applying a suitably chosen threshold for the calculated correlation values, a segment is prescribed to be either clean or noisy. As a key merit of this research, the procedure can introduce a decision support for choosing accurately orthogonal-expansion-based filtering or to remove noisy segments. In this paper, the application procedure of the proposed method is comprehensively described by applying it to phonocardiogram (PCG) signals for finding noisy cycles. The database consists of 126 records from several patients of a domestic research station acquired by a 3M Littmann(®) 3200, 4KHz sampling frequency electronic stethoscope. By implementing the noisy segments detection algorithm with this database, a sensitivity of Se=91.41% and a positive predictive value, PPV=92.86% were obtained based on physicians assessments. Copyright © 2013 Elsevier Ltd. All rights reserved.

Private rural health providers in Haryana, India: profile and practices.

PubMed

Jarhyan, P; Singh, B; Rai, S K; Nongkynrih, B

2012-01-01

Despite a widespread public health system, the private healthcare sector is the major provider of health care in rural India. This study describes the profile and medical practices of private rural health providers (PRHPs) in rural Haryana, India. A cross-sectional study was conducted among PRHPs practicing in the villages of Comprehensive Rural Health Services Project (CRHSP) at Ballabgarh block located in the Faridabad district of Haryana State. The CRHSP is an Intensive Field Practice Area (IFPA) of the Centre for Community Medicine, All India Institute of Medical Sciences, New Delhi. Eighty PRHPs participated in this study (response rate 93%). The majority (96%) did not possess a qualification in any formal system of medicine. Half of the PRHPs had a separate space (private area) for the examination of patients. Almost all had stethoscopes, thermometers and blood pressure apparatus. The PRHPs were involved in a wide range of practices, such as dispensing medicines (98.7%), providing injections (98.7%) and intravenous fluids (98.7%), and conducting minor surgery (78.5%). Dumping biomedical waste was a common practice among these practitioners. Some PRHPs (8.7%) were involved in national health programs. Unqualified PRHPs provide substantial outpatient healthcare services in rural Ballabgarh, India. Their biomedical waste disposal practices are inadequate. There is a need for training in waste disposal practices and monitoring of safe injection techniques among PRHPs. Consideration should be given to utilising PRHPs in important public health programs such as disease surveillance.

Point-of-care cardiac ultrasound techniques in the physical examination: better at the bedside.

PubMed

Kimura, Bruce J

2017-07-01

The development of hand-carried, battery-powered ultrasound devices has created a new practice in ultrasound diagnostic imaging, called 'point-of-care' ultrasound (POCUS). Capitalising on device portability, POCUS is marked by brief and limited ultrasound imaging performed by the physician at the bedside to increase diagnostic accuracy and expediency. The natural evolution of POCUS techniques in general medicine, particularly with pocket-sized devices, may be in the development of a basic ultrasound examination similar to the use of the binaural stethoscope. This paper will specifically review how POCUS improves the limited sensitivity of the current practice of traditional cardiac physical examination by both cardiologists and non-cardiologists. Signs of left ventricular systolic dysfunction, left atrial enlargement, lung congestion and elevated central venous pressures are often missed by physical techniques but can be easily detected by POCUS and have prognostic and treatment implications. Creating a general set of repetitive imaging skills for these entities for application on all patients during routine examination will standardise and reduce heterogeneity in cardiac bedside ultrasound applications, simplify teaching curricula, enhance learning and recollection, and unify competency thresholds and practice. The addition of POCUS to standard physical examination techniques in cardiovascular medicine will result in an ultrasound-augmented cardiac physical examination that reaffirms the value of bedside diagnosis. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Enhancing Health-Care Services with Mixed Reality Systems

NASA Astrophysics Data System (ADS)

Stantchev, Vladimir

This work presents a development approach for mixed reality systems in health care. Although health-care service costs account for 5-15% of GDP in developed countries the sector has been remarkably resistant to the introduction of technology-supported optimizations. Digitalization of data storing and processing in the form of electronic patient records (EPR) and hospital information systems (HIS) is a first necessary step. Contrary to typical business functions (e.g., accounting or CRM) a health-care service is characterized by a knowledge intensive decision process and usage of specialized devices ranging from stethoscopes to complex surgical systems. Mixed reality systems can help fill the gap between highly patient-specific health-care services that need a variety of technical resources on the one side and the streamlined process flow that typical process supporting information systems expect on the other side. To achieve this task, we present a development approach that includes an evaluation of existing tasks and processes within the health-care service and the information systems that currently support the service, as well as identification of decision paths and actions that can benefit from mixed reality systems. The result is a mixed reality system that allows a clinician to monitor the elements of the physical world and to blend them with virtual information provided by the systems. He or she can also plan and schedule treatments and operations in the digital world depending on status information from this mixed reality.

Social supports and mental health: a cross-sectional study on the correlation of self-consistency and congruence in China.

PubMed

Gu, YanMei; Hu, Jie; Hu, YaPing; Wang, JianRong

2016-06-28

Psychosocial job characteristics require nursing staff with high self-consistency and good mental health. However, the attention and effort of such study remained very limited in China. A self-administered questionnaire was distributed to the bedside nurses in an affiliated hospital of Hebei Medical University, China. Of 218 registered bedside nurses eligible to participate in the survey anonymously, the data producing sample of 172 subjects resulted in a 79 % of effective response rate.. The Social Support Rating Scale was used to measure social support, and the Self-Consistency and Congruence Scale were used to measure mental health. Compared with the normal referenced group of college students, higher self-flexibility scores, lower self-conflict and self-stethoscope scores from the sample group were obtained with statistical significance in self-conflict scores. The close correlations were observed between participants' social support and Self-Consistency and Congruence Scale score. The difference of Social Support Rating Scale score was significant in demographic features including years of work, marital status, only child family, and levels of cooperation with other health worker. Bedside nurses in this study show a better inner harmony, and their Self-Consistency and Congruence closely correlates with the levels of social support. Thus, it is substantial to improve inner perception of support and external factors, such as the workplace support, and offer beneficial social environment to improve the bedside nurse's sub-health symptoms and decrease the high turnover rate.

Accuracy of abdominal auscultation for bowel obstruction.

PubMed

Breum, Birger Michael; Rud, Bo; Kirkegaard, Thomas; Nordentoft, Tyge

2015-09-14

To investigate the accuracy and inter-observer variation of bowel sound assessment in patients with clinically suspected bowel obstruction. Bowel sounds were recorded in patients with suspected bowel obstruction using a Littmann(®) Electronic Stethoscope. The recordings were processed to yield 25-s sound sequences in random order on PCs. Observers, recruited from doctors within the department, classified the sound sequences as either normal or pathological. The reference tests for bowel obstruction were intraoperative and endoscopic findings and clinical follow up. Sensitivity and specificity were calculated for each observer and compared between junior and senior doctors. Interobserver variation was measured using the Kappa statistic. Bowel sound sequences from 98 patients were assessed by 53 (33 junior and 20 senior) doctors. Laparotomy was performed in 47 patients, 35 of whom had bowel obstruction. Two patients underwent colorectal stenting due to large bowel obstruction. The median sensitivity and specificity was 0.42 (range: 0.19-0.64) and 0.78 (range: 0.35-0.98), respectively. There was no significant difference in accuracy between junior and senior doctors. The median frequency with which doctors classified bowel sounds as abnormal did not differ significantly between patients with and without bowel obstruction (26% vs 23%, P = 0.08). The 53 doctors made up 1378 unique pairs and the median Kappa value was 0.29 (range: -0.15-0.66). Accuracy and inter-observer agreement was generally low. Clinical decisions in patients with possible bowel obstruction should not be based on auscultatory assessment of bowel sounds.

Swallowing sounds in speech therapy practice: a critical analysis of the literature

PubMed Central

Ferrucci, Juliana Lopes; Mangilli, Laura Davison; Sassi, Fernanda Chiarion; Limongi, Suelly Cecilia Olivan; de Andrade, Claudia Regina Furquim

2013-01-01

ABSTRACT This study aimed to investigate international scientific papers published on the subject of cervical auscultation and its use in speech therapy. The study involved a qualitative review of the literature spanning the last 10 years. Articles were selected from the PubMed database using the following keywords: cervical auscultation, swallowing and swallowing disorders. Research was included that was conducted on adult humans (over 18 years of age) and was written in English. Each citation retrieved from the database was analyzed independently by each of the study researchers to ascertain its relevance for inclusion in the study. The methodology involved formulating the research question, locating and selecting studies and critically evaluating the articles according to the precepts of the Cochrane Handbook. As a result, 35 studies were identified; 13 articles were analyzed because they allowed access to the full text and were related directly to the subject. We found that the studies were performed with groups of healthy subjects and subjects with different types of base pathology. Some studies compared the patterns found in the different groups. Some of the research sought to study the pattern of swallowing sounds with different factors - evaluator experience, the specificity and sensitivity of the method and how to improve the technique of cervical auscultation through the use of instruments other than the stethoscope. The conclusion of this critical analysis is that cervical auscultation is an important tool to be used in conjunction with other assessment methods in the routine clinical evaluation of swallowing. PMID:24488399

A comparison between swallowing sounds and vibrations in patients with dysphagia

PubMed Central

Movahedi, Faezeh; Kurosu, Atsuko; Coyle, James L.; Perera, Subashan

2017-01-01

The cervical auscultation refers to the observation and analysis of sounds or vibrations captured during swallowing using either a stethoscope or acoustic/vibratory detectors. Microphones and accelerometers have recently become two common sensors used in modern cervical auscultation methods. There are open questions about whether swallowing signals recorded by these two sensors provide unique or complementary information about swallowing function; or whether they present interchangeable information. The aim of this study is to present a broad comparison of swallowing signals recorded by a microphone and a tri-axial accelerometer from 72 patients (mean age 63.94 ± 12.58 years, 42 male, 30 female), who underwent videofluoroscopic examination. The participants swallowed one or more boluses of thickened liquids of different consistencies, including thin liquids, nectar-thick liquids, and pudding. A comfortable self-selected volume from a cup or a controlled volume by the examiner from a 5ml spoon was given to the participants. A comprehensive set of features was extracted in time, information-theoretic, and frequency domains from each of 881 swallows presented in this study. The swallowing sounds exhibited significantly higher frequency content and kurtosis values than the swallowing vibrations. In addition, the Lempel-Ziv complexity was lower for swallowing sounds than those for swallowing vibrations. To conclude, information provided by microphones and accelerometers about swallowing function are unique and these two transducers are not interchangeable. Consequently, the selection of transducer would be a vital step in future studies. PMID:28495001

Wavelet packet-based insufficiency murmurs analysis method

NASA Astrophysics Data System (ADS)

Choi, Samjin; Jiang, Zhongwei

2007-12-01

In this paper, the aortic and mitral insufficiency murmurs analysis method using the wavelet packet technique is proposed for classifying the valvular heart defects. Considering the different frequency distributions between the normal sound and insufficiency murmurs in frequency domain, we used two properties such as the relative wavelet energy and the Shannon wavelet entropy which described the energy information and the entropy information at the selected frequency band, respectively. Then, the signal to murmur ratio (SMR) measures which could mean the ratio between the frequency bands for normal heart sounds and for aortic and mitral insufficiency murmurs allocated to 15.62-187.50 Hz and 187.50-703.12 Hz respectively, were employed as a classification manner to identify insufficiency murmurs. The proposed measures were validated by some case studies. The 194 heart sound signals with 48 normal and 146 abnormal sound cases acquired from 6 healthy volunteers and 30 patients were tested. The normal sound signals recorded by applying a self-produced wireless electric stethoscope system to subjects with no history of other heart complications were used. Insufficiency murmurs were grouped into two valvular heart defects such as aortic insufficiency and mitral insufficiency. These murmur subjects included no other coexistent valvular defects. As a result, the proposed insufficiency murmurs detection method showed relatively very high classification efficiency. Therefore, the proposed heart sound classification method based on the wavelet packet was validated for the classification of valvular heart defects, especially insufficiency murmurs.

Optimal wavelet denoising for smart biomonitor systems

NASA Astrophysics Data System (ADS)

Messer, Sheila R.; Agzarian, John; Abbott, Derek

2001-03-01

Future smart-systems promise many benefits for biomedical diagnostics. The ideal is for simple portable systems that display and interpret information from smart integrated probes or MEMS-based devices. In this paper, we will discuss a step towards this vision with a heart bio-monitor case study. An electronic stethoscope is used to record heart sounds and the problem of extracting noise from the signal is addressed via the use of wavelets and averaging. In our example of heartbeat analysis, phonocardiograms (PCGs) have many advantages in that they may be replayed and analysed for spectral and frequency information. Many sources of noise may pollute a PCG including foetal breath sounds if the subject is pregnant, lung and breath sounds, environmental noise and noise from contact between the recording device and the skin. Wavelets can be employed to denoise the PCG. The signal is decomposed by a discrete wavelet transform. Due to the efficient decomposition of heart signals, their wavelet coefficients tend to be much larger than those due to noise. Thus, coefficients below a certain level are regarded as noise and are thresholded out. The signal can then be reconstructed without significant loss of information in the signal. The questions that this study attempts to answer are which wavelet families, levels of decomposition, and thresholding techniques best remove the noise in a PCG. The use of averaging in combination with wavelet denoising is also addressed. Possible applications of the Hilbert Transform to heart sound analysis are discussed.

Non-proximate mass spectrometry using a heated 1-m long PTFE tube and an air-tight APCI ion source.

PubMed

Usmanov, Dilshadbek T; Hiraoka, Kenzo; Wada, Hiroshi; Matsumura, Masaya; Sanada-Morimura, Sachiyo; Nonami, Hiroshi; Yamabe, Shinichi

2017-06-22

Direct and rapid trace-level gas analysis is highly needed in various fields such as safety and security, quality control, food analysis, and forensic medicine. In many cases, the real samples are bulky and are not accessible to the space-limited ion source of the mass spectrometer. In order to circumvent this problem, we developed an airtight atmospheric-pressure chemical ionization (APCI) ion source equipped with a flexible 1-m-long, 2-mm-i.d. PTFE sniffing tube. The ambient air bearing sample gas was sucked into the heated PTFE tube (130 °C) and was transported to the air-tight ion source without using any extra pumping system or a Venturi device. Analytes were ionized by an ac corona discharge located at 1.5 mm from the inlet of the mass spectrometer. By using the airtight ion source, all the ionized gas in the ion source was introduced into the vacuum of the mass spectrometer via only the evacuation of the mass spectrometer (1.6 l min -1 ). Sub-pg limits of detection were obtained for carbaryl and trinitrotoluene. Owing to its flexibility and high sensitivity, the sniffing tube coupled with a mass spectrometer can be used as the stethoscope for the high-sensitive gas analysis. The experimental results obtained for drugs, hydrogen peroxide and small alkanes were discussed by DFT calculations. Copyright © 2017 Elsevier B.V. All rights reserved.

High frequency analysis of cough sounds in pediatric patients with respiratory diseases.

PubMed

Kosasih, K; Abeyratne, U R; Swarnkar, V

2012-01-01

Cough is a common symptom in a range of respiratory diseases and is considered a natural defense mechanism of the body. Despite its critical importance in the diagnosis of illness, there are no golden methods to objectively assess cough. In a typical consultation session, a physician may briefly listen to the cough sounds using a stethoscope placed against the chest. The physician may also listen to spontaneous cough sounds via naked ears, as they naturally propagate through air. Cough sounds carry vital information on the state of the respiratory system but the field of cough analysis in clinical medicine is in its infancy. All existing cough analysis approaches are severely handicapped by the limitations of the human hearing range and simplified analysis techniques. In this paper, we address these problems, and explore the use of frequencies covering a range well beyond the human perception (up to 90 kHz) and use wavelet analysis to extract diagnostically important information from coughs. Our data set comes from a pediatric respiratory ward in Indonesia, from subjects diagnosed with asthma, pneumonia and rhinopharyngitis. We analyzed over 90 cough samples from 4 patients and explored if high frequencies carried useful information in separating these disease groups. Multiple regression analysis resulted in coefficients of determination (R(2)) of 77-82% at high frequencies (15 kHz-90 kHz) indicating that they carry useful information. When the high frequencies were combined with frequencies below 15kHz, the R(2) performance increased to 85-90%.

[A new medical education using a lung sound auscultation simulator called "Mr. Lung"].

PubMed

Yoshii, Chiharu; Anzai, Takashi; Yatera, Kazuhiro; Kawajiri, Tatsunori; Nakashima, Yasuhide; Kido, Masamitsu

2002-09-01

We developed a lung sound auscultation simulator "Mr. Lung" in 2001. To improve the auscultation skills of lung sounds, we utilized this new device in our educational training facility. From June 2001 to March 2002, we used "Mr. Lung" for our small group training in which one hundred of the fifth year medical students were divided into small groups from which one group was taught every other week. The class consisted of ninety-minute training periods for auscultation of lung sounds. At first, we explained the classification of lung sounds, and then auscultation tests were performed. Namely, students listened to three cases of abnormal or adventitious lung sounds on "Mr. Lung" through their stethoscopes. Next they answered questions corresponding to the portion and quality of the sounds. Then, we explained the correct answers and how to differentiate lung sounds on "Mr. Lung". Additionally, at the beginning and the end of the lecture, five degrees of self-assessment for the auscultation of the lung sounds were performed. The ratio of correct answers for lung sounds were 36.9% for differences between bilateral lung sounds, 52.5% for coarse crackles, 34.1% for fine crackles, 69.2% for wheezes, 62.1% for rhonchi and 22.2% for stridor. Self-assessment scores were significantly higher after the class than before. The ratio of correct lung sound answers was surprisingly low among medical students. We believe repetitive auscultation of the simulator to be extremely helpful for medical education.

Computerized Lung Sound Analysis as diagnostic aid for the detection of abnormal lung sounds: a systematic review and meta-analysis

PubMed Central

Gurung, Arati; Scrafford, Carolyn G; Tielsch, James M; Levine, Orin S; Checkley, William

2011-01-01

Rationale The standardized use of a stethoscope for chest auscultation in clinical research is limited by its inherent inter-listener variability. Electronic auscultation and automated classification of recorded lung sounds may help prevent some these shortcomings. Objective We sought to perform a systematic review and meta-analysis of studies implementing computerized lung sounds analysis (CLSA) to aid in the detection of abnormal lung sounds for specific respiratory disorders. Methods We searched for articles on CLSA in MEDLINE, EMBASE, Cochrane Library and ISI Web of Knowledge through July 31, 2010. Following qualitative review, we conducted a meta-analysis to estimate the sensitivity and specificity of CLSA for the detection of abnormal lung sounds. Measurements and Main Results Of 208 articles identified, we selected eight studies for review. Most studies employed either electret microphones or piezoelectric sensors for auscultation, and Fourier Transform and Neural Network algorithms for analysis and automated classification of lung sounds. Overall sensitivity for the detection of wheezes or crackles using CLSA was 80% (95% CI 72–86%) and specificity was 85% (95% CI 78–91%). Conclusions While quality data on CLSA are relatively limited, analysis of existing information suggests that CLSA can provide a relatively high specificity for detecting abnormal lung sounds such as crackles and wheezes. Further research and product development could promote the value of CLSA in research studies or its diagnostic utility in clinical setting. PMID:21676606

Computerized lung sound analysis as diagnostic aid for the detection of abnormal lung sounds: a systematic review and meta-analysis.

PubMed

Gurung, Arati; Scrafford, Carolyn G; Tielsch, James M; Levine, Orin S; Checkley, William

2011-09-01

The standardized use of a stethoscope for chest auscultation in clinical research is limited by its inherent inter-listener variability. Electronic auscultation and automated classification of recorded lung sounds may help prevent some of these shortcomings. We sought to perform a systematic review and meta-analysis of studies implementing computerized lung sound analysis (CLSA) to aid in the detection of abnormal lung sounds for specific respiratory disorders. We searched for articles on CLSA in MEDLINE, EMBASE, Cochrane Library and ISI Web of Knowledge through July 31, 2010. Following qualitative review, we conducted a meta-analysis to estimate the sensitivity and specificity of CLSA for the detection of abnormal lung sounds. Of 208 articles identified, we selected eight studies for review. Most studies employed either electret microphones or piezoelectric sensors for auscultation, and Fourier Transform and Neural Network algorithms for analysis and automated classification of lung sounds. Overall sensitivity for the detection of wheezes or crackles using CLSA was 80% (95% CI 72-86%) and specificity was 85% (95% CI 78-91%). While quality data on CLSA are relatively limited, analysis of existing information suggests that CLSA can provide a relatively high specificity for detecting abnormal lung sounds such as crackles and wheezes. Further research and product development could promote the value of CLSA in research studies or its diagnostic utility in clinical settings. Copyright © 2011 Elsevier Ltd. All rights reserved.

Application of semi-supervised deep learning to lung sound analysis.

PubMed

Chamberlain, Daniel; Kodgule, Rahul; Ganelin, Daniela; Miglani, Vivek; Fletcher, Richard Ribon

2016-08-01

The analysis of lung sounds, collected through auscultation, is a fundamental component of pulmonary disease diagnostics for primary care and general patient monitoring for telemedicine. Despite advances in computation and algorithms, the goal of automated lung sound identification and classification has remained elusive. Over the past 40 years, published work in this field has demonstrated only limited success in identifying lung sounds, with most published studies using only a small numbers of patients (typically N<;20) and usually limited to a single type of lung sound. Larger research studies have also been impeded by the challenge of labeling large volumes of data, which is extremely labor-intensive. In this paper, we present the development of a semi-supervised deep learning algorithm for automatically classify lung sounds from a relatively large number of patients (N=284). Focusing on the two most common lung sounds, wheeze and crackle, we present results from 11,627 sound files recorded from 11 different auscultation locations on these 284 patients with pulmonary disease. 890 of these sound files were labeled to evaluate the model, which is significantly larger than previously published studies. Data was collected with a custom mobile phone application and a low-cost (US$30) electronic stethoscope. On this data set, our algorithm achieves ROC curves with AUCs of 0.86 for wheeze and 0.74 for crackle. Most importantly, this study demonstrates how semi-supervised deep learning can be used with larger data sets without requiring extensive labeling of data.

An experience with trial of scar in 66 Ethiopian women.

PubMed

Sebhatu, B

1994-10-01

The purpose of this study was to determine the circumstances in which trial of scar is conducted in the obstetric unit of Tikur Anbessa Hospital, Addis Ababa, Ethiopia, and evaluate the safety of the undertaking in terms of maternal and perinatal morbidity and mortality. Between 11 September, 1991 to 10 September, 1992, 66 women with previous caesarean section were given a trial of scar. The main pre-requests to allow a trial of scar were: only one previous lower uterine segment section, a cephalic presentation with no disproportion in the current labour and, the presence of a functional operating theatre. Labour was being monitored by checking the uterine contractions by fundal palpation and counting the Foetal heart rate (FHR) using the Pinnard Stethoscope. Compatible blood was prior prepared in only 7 (10.6%) labours. Forty seven (71.2%) parturients delivered vaginally. In 19 (28.2%) an emergency repeat section was done for failure of progress in labour. In one (1.5%) patient, a uterine scar dehiscence was detected. The 5th minute APGAR score was 7/10 or more in 64 (94.1%) and 6/10 in 3 (4.5%) of 68 neonates. There was one prepartum intra-uterine foetal death and one neonatal death of a preterm baby making the perinatal mortality rate (PNMR) of 29.4 per thousand. There was no maternal death. In conclusion, this study demonstrates that a trial of scar was a safe procedure.

Home birth attendants in low income countries: who are they and what do they do?

PubMed Central

2012-01-01

Background Nearly half the world’s babies are born at home. We sought to evaluate the training, knowledge, skills, and access to medical equipment and testing for home birth attendants across 7 international sites. Methods Face-to-face interviews were done by trained interviewers to assess level of training, knowledge and practices regarding care during the antenatal, intrapartum and postpartum periods. The survey was administered to a sample of birth attendants conducting home or out-of-facility deliveries in 7 sites in 6 countries (India, Pakistan, Guatemala, Democratic Republic of the Congo, Kenya and Zambia). Results A total of 1226 home birth attendants were surveyed. Less than half the birth attendants were literate. Eighty percent had one month or less of formal training. Most home birth attendants did not have basic equipment (e.g., blood pressure apparatus, stethoscope, infant bag and mask manual resuscitator). Reporting of births and maternal and neonatal deaths to government agencies was low. Indian auxilliary nurse midwives, who perform some home but mainly clinic births, were far better trained and differed in many characteristics from the birth attendants who only performed deliveries at home. Conclusions Home birth attendants in low-income countries were often illiterate, could not read numbers and had little formal training. Most had few of the skills or access to tests, medications and equipment that are necessary to reduce maternal, fetal or neonatal mortality. PMID:22583622

Gliding Swifts Attain Laminar Flow over Rough Wings

PubMed Central

Lentink, David; de Kat, Roeland

2014-01-01

Swifts are among the most aerodynamically refined gliding birds. However, the overlapping vanes and protruding shafts of their primary feathers make swift wings remarkably rough for their size. Wing roughness height is 1–2% of chord length on the upper surface—10,000 times rougher than sailplane wings. Sailplanes depend on extreme wing smoothness to increase the area of laminar flow on the wing surface and minimize drag for extended glides. To understand why the swift does not rely on smooth wings, we used a stethoscope to map laminar flow over preserved wings in a low-turbulence wind tunnel. By combining laminar area, lift, and drag measurements, we show that average area of laminar flow on swift wings is 69% (n = 3; std 13%) of their total area during glides that maximize flight distance and duration—similar to high-performance sailplanes. Our aerodynamic analysis indicates that swifts attain laminar flow over their rough wings because their wing size is comparable to the distance the air travels (after a roughness-induced perturbation) before it transitions from laminar to turbulent. To interpret the function of swift wing roughness, we simulated its effect on smooth model wings using physical models. This manipulation shows that laminar flow is reduced and drag increased at high speeds. At the speeds at which swifts cruise, however, swift-like roughness prolongs laminar flow and reduces drag. This feature gives small birds with rudimentary wings an edge during the evolution of glide performance. PMID:24964089

Preclinical medical students’ understandings of academic and medical professionalism: visual analysis of mind maps

PubMed Central

Rees, Charlotte E

2017-01-01

Introduction Several studies have begun to explore medical students’ understandings of professionalism generally and medical professionalism specifically. Despite espoused relationships between academic (AP) and medical professionalism (MP), previous research has not yet investigated students’ conceptualisations of AP and MP and the relationships between the two. Objectives The current study, based on innovative visual analysis of mind maps, therefore aims to contribute to the developing literature on how professionalism is understood. Methods We performed a multilayered analysis of 98 mind maps from 262 first-year medical students, including analysing textual and graphical elements of AP, MP and the relationships between AP and MP. Results The most common textual attributes of AP were learning, lifestyle and personality, while attributes of MP were knowledge, ethics and patient-doctor relations. Images of books, academic caps and teachers were used most often to represent AP, while images of the stethoscope, doctor and red cross were used to symbolise MP. While AP-MP relations were sometimes indicated through co-occurring text, visual connections and higher-order visual metaphors, many students struggled to articulate the relationships between AP and MP. Conclusions While the mind maps’ textual attributes shared similarities with those found in previous research, suggesting the universality of some professionalism attributes, our study provides new insights into students’ conceptualisations of AP, MP and AP-MP relationships. We encourage medical educators to help students develop their understandings of AP, MP and AP-MP relationships, plus consider the feasibility and value of mind maps as a source of visual data for medical education research. PMID:28821520

Determining the utility and durability of medical equipment donated to a rural clinic in a low-income country

PubMed Central

Bauserman, Melissa; Hailey, Claire; Gado, Justin; Lokangaka, Adrien; Williams, Jessica; Richards-Kortum, Rebecca; Tshefu, Antoinette; Bose, Carl

2015-01-01

Background Health centers in low-income countries often depend on donations to provide appropriate diagnostic equipment. However, donations are sometimes made without an understanding of the recipient's needs, practical constraints or sustainability of supplies. Methods We donated a set of physical diagnostic equipment, non-invasive instrument tests and laboratory supplies to a rural health center in the Democratic Republic of Congo. We collected information on the usage and durability of equipment and supplies for each patient encounter over a 1-year period. Results We recorded 913 patient encounters. The most commonly used physical diagnostic equipment were the stethoscope (98.9%; 903/913), thermometer (81.7%; 746/913), adult scale (81.4%; 744/913), stop watch (62.6%; 572/913), adult sphygmomanometer (55.8%; 510/913), infant scale (24.9%; 228/913), measuring tape (24.3%; 222/913) and fetoscope (23.8%; 218/913). The most commonly used laboratory tests were the blood smear for malaria (53.7%; 491/913), hematocrit (23.5%; 215/913), urinalysis (20.1%; 184/913) and sputum stain for TB (13.3%; 122/913). With the exception of a penlight and solar lantern, all equipment remained functional. Conclusions This study adds valuable information about the utility and durability of equipment supplied to a health center in the Democratic Republic of Congo. Our results might aid in determining the appropriateness of donated medical equipment in similar settings. The selection of donated goods should be made with knowledge of the context in which it will be used, and utilization should be monitored. PMID:25525132

Discrete wavelet-aided delineation of PCG signal events via analysis of an area curve length-based decision statistic.

PubMed

Homaeinezhad, M R; Atyabi, S A; Daneshvar, E; Ghaffari, A; Tahmasebi, M

2010-12-01

The aim of this study is to describe a robust unified framework for segmentation of the phonocardiogram (PCG) signal sounds based on the false-alarm probability (FAP) bounded segmentation of a properly calculated detection measure. To this end, first the original PCG signal is appropriately pre-processed and then, a fixed sample size sliding window is moved on the pre-processed signal. In each slid, the area under the excerpted segment is multiplied by its curve-length to generate the Area Curve Length (ACL) metric to be used as the segmentation decision statistic (DS). Afterwards, histogram parameters of the nonlinearly enhanced DS metric are used for regulation of the α-level Neyman-Pearson classifier for FAP-bounded delineation of the PCG events. The proposed method was applied to all 85 records of Nursing Student Heart Sounds database (NSHSDB) including stenosis, insufficiency, regurgitation, gallop, septal defect, split sound, rumble, murmur, clicks, friction rub and snap disorders with different sampling frequencies. Also, the method was applied to the records obtained from an electronic stethoscope board designed for fulfillment of this study in the presence of high-level power-line noise and external disturbing sounds and as the results, no false positive (FP) or false negative (FN) errors were detected. High noise robustness, acceptable detection-segmentation accuracy of PCG events in various cardiac system conditions, and having no parameters dependency to the acquisition sampling frequency can be mentioned as the principal virtues and abilities of the proposed ACL-based PCG events detection-segmentation algorithm.

Deafness among physicians and trainees: a national survey.

PubMed

Moreland, Christopher J; Latimore, Darin; Sen, Ananda; Arato, Nora; Zazove, Philip

2013-02-01

To describe the characteristics of and accommodations used by the deaf and hard-of-hearing (DHoH) physician and trainee population and examine whether these individuals are more likely to care for DHoH patients. Multipronged snowball sampling identified 86 potential DHoH physician and trainee participants. In July to September 2010, a Web-based survey investigated accommodations used by survey respondents. The authors analyzed participants' demographics, accommodation and career satisfaction, sense of institutional support, likelihood of recommending medicine as a career, and current/anticipated DHoH patient population size. The response rate was 65% (56 respondents; 31 trainees and 25 practicing physicians). Modified stethoscopes were the most frequently used accommodation (n = 50; 89%); other accommodations included auditory equipment, note-taking, computer-assisted real-time captioning, signed interpretation, and oral interpretation. Most respondents reported that their accommodations met their needs well, although 2 spent up to 10 hours weekly arranging accommodations. Of 25 physicians, 17 reported primary care specialties; 7 of 31 trainees planned to enter primary care specialties. Over 20% of trainees anticipated working with DHoH patients, whereas physicians on average spent 10% of their time with DHoH patients. Physicians' accommodation satisfaction was positively associated with career satisfaction and recommending medicine as a career. DHoH physicians and trainees seemed satisfied with frequent, multimodal accommodations from employers and educators. These results may assist organizations in planning accommodation provisions. Because DHoH physicians and trainees seem interested in primary care and serving DHoH patients, recruiting and training DHoH physicians has implications for the care of this underserved population.

Bridging the Gaps Between Patients and Primary Care in China: A Nationwide Representative Survey

PubMed Central

Wong, William C. W.; Jiang, Sunfang; Ong, Jason J.; Peng, Minghui; Wan, Eric; Zhu, Shanzhu; Lam, Cindy L. K.; Kidd, Michael R.; Roland, Martin

2017-01-01

PURPOSE China introduced a national policy of developing primary care in 2009, establishing 8,669 community health centers (CHCs) by 2014 that employed more than 300,000 staff. These facilities have been underused, however, because of public mistrust of physicians and overreliance on specialist care. METHODS We selected a stratified random sample of CHCs throughout China based on geographic distribution and urban-suburban ratios between September and December 2015. Two questionnaires, 1 for lead clinicians and 1 for primary care practitioners (PCPs), asked about the demographics of the clinic and its clinical and educational activities. Responses were obtained from 158 lead clinicians in CHCs and 3,580 PCPs (response rates of 84% and 86%, respectively). RESULTS CHCs employed a median of 8 physicians and 13 nurses, but only one-half of physicians were registered as PCPs, and few nurses had training specifically for primary care. Although virtually all clinics were equipped with stethoscopes (98%) and sphygmomanometers (97%), only 43% had ophthalmoscopes and 64% had facilities for gynecologic examination. Clinical care was selectively skewed toward certain chronic diseases. Physicians saw a median of 12.5 patients per day. Multivariate analysis showed that more patients were seen daily by physicians in CHCs organized by private hospitals and those having pharmacists and nurses. CONCLUSIONS Our survey confirms China’s success in establishing a large, mostly young primary care workforce and providing ongoing professional training. Facilities are basic, however, with few clinics providing the comprehensive primary care required for a wide range of common physical and mental conditions. Use of CHCs by patients remains low. PMID:28483889

Pierre Adolphe Piorry (1794-1879): pioneer of percussion and pleximetry.

PubMed Central

Sakula, A

1979-01-01

Piorry was born in Poitiers on 31 December 1794. As a medical student he served in the Napoleonic war in Spain. His teachers in medicine included Corvisart, Bayle, Broussais, and Magendie; he qualified in 1816 with an MD thesis: "On the danger of reading medical text books by the laity"! Laënnec's invention of the stethoscope (1816) and De l' Auscultation Médiate (1819) inspired Piorry to make an analogous contribution to the technique of percussion (which had been originally described by Auenbrugger in his Inventum Novum in 1761 and translated from the Latin into French by Corvisart in 1808). This led to Piorry's invention in 1826 of the pleximeter (le plessimétre) to help outline the internal organs (l'organographisme), which he described inDe la Percussion Médiate (1828). Piorry became renowned as a professor of medicine in many of the great Parisian hospitals (Charité, Pitié, and Hôtel Dieux). In 1832 he was appointed to L'Hospice de la Salpétrière, where he held a famous course of clinical lectures. He wrote prolificly on many aspects of medicine and published more than twenty books. He was, in addition, a poet of some distinction, and wrote a remarkable long poem Dieu, L'Ame et la Nature (1853). Piorry held his neologisms-for example, toxin, toxaemia, septicaemia, etc.-are still in use. This, together with the mixed reception that his advocacy of pleximetry received from his medical contemporaries, made him a controversial figure. He died on 29 May 1879. Images PMID:390757

Pharmaceutical advertising in emergency departments.

PubMed

Marco, Catherine A

2004-04-01

Promotion of prescription drugs represents a growing source of pharmaceutical marketing expenditures. This study was undertaken to identify the frequency of items containing pharmaceutical advertising in clinical emergency departments (EDs). In this observational study, emergency physician on-site investigators quantified a variety of items containing pharmaceutical advertising present at specified representative times and days, in clinical EDs. Measurements were obtained by 65 on-site investigators, representing 22 states. Most EDs in this study were community EDs (87% community and 14% university or university affiliate), and most were in urban settings (50% urban, 38% suburban, and 13% rural). Investigators measured 42 items per ED (mean = 42; median = 31; interquartile range of 14-55) containing pharmaceutical advertising in the clinical area. The most commonly observed items included pens (mean 15 per ED; median 10), product brochures (mean 5; median 3), stethoscope labels (mean 4; median 2), drug samples (mean 3; median 0), books (mean 3.4), mugs (mean 2.4), and published literature (mean 3.1). EDs with a policy restricting pharmaceutical representatives in the ED had significantly fewer items containing pharmaceutical advertising (median 7.5; 95% CI = 0 to 27) than EDs without such a policy (median 35; 95% CI = 27 to 47, p = 0.005, nonparametric Wilcoxon two-sample test). There were no differences in quantities of pharmaceutical advertising for EDs in community compared with university settings (p = 0.5), rural compared with urban settings (p = 0.3), or annual ED volumes (p = 0.9). Numerous items containing pharmaceutical advertising are frequently observed in EDs. Policies restricting pharmaceutical representatives in the ED are associated with reduced pharmaceutical advertising.

Accuracy of abdominal auscultation for bowel obstruction

PubMed Central

Breum, Birger Michael; Rud, Bo; Kirkegaard, Thomas; Nordentoft, Tyge

2015-01-01

AIM: To investigate the accuracy and inter-observer variation of bowel sound assessment in patients with clinically suspected bowel obstruction. METHODS: Bowel sounds were recorded in patients with suspected bowel obstruction using a Littmann® Electronic Stethoscope. The recordings were processed to yield 25-s sound sequences in random order on PCs. Observers, recruited from doctors within the department, classified the sound sequences as either normal or pathological. The reference tests for bowel obstruction were intraoperative and endoscopic findings and clinical follow up. Sensitivity and specificity were calculated for each observer and compared between junior and senior doctors. Interobserver variation was measured using the Kappa statistic. RESULTS: Bowel sound sequences from 98 patients were assessed by 53 (33 junior and 20 senior) doctors. Laparotomy was performed in 47 patients, 35 of whom had bowel obstruction. Two patients underwent colorectal stenting due to large bowel obstruction. The median sensitivity and specificity was 0.42 (range: 0.19-0.64) and 0.78 (range: 0.35-0.98), respectively. There was no significant difference in accuracy between junior and senior doctors. The median frequency with which doctors classified bowel sounds as abnormal did not differ significantly between patients with and without bowel obstruction (26% vs 23%, P = 0.08). The 53 doctors made up 1378 unique pairs and the median Kappa value was 0.29 (range: -0.15-0.66). CONCLUSION: Accuracy and inter-observer agreement was generally low. Clinical decisions in patients with possible bowel obstruction should not be based on auscultatory assessment of bowel sounds. PMID:26379407

High-fidelity digital recording and playback sphygmomanometry system: device description and proof of concept.

PubMed

Lee, Jongshill; Chee, Youngjoon; Kim, Inyoung; Karpettas, Nikos; Kollias, Anastasios; Atkins, Neil; Stergiou, George S; O'Brien, Eoin

2015-10-01

This study describes the development of a new digital sphygmocorder (DS-II), which allows the digital recording and playback of the Korotkoff sounds, together with cuff pressure waveform, and its performance in a pilot validation study. A condenser microphone and stethoscope head detect Korotkoff sounds and an electronic chip, dedicated to audio-signal processing, is used to record high-quality sounds. Systolic and diastolic blood pressure (SBP/DBP) are determined from the recorded signals with an automatic beat detection algorithm that displays the cuff pressure at each beat on the monitor. Recordings of Korotkoff sounds, with the cuff pressure waveforms, and the simultaneous on-site assessments of SBP/DBP were performed during 100 measurements in 10 individuals. The observers reassessed the recorded signals to verify their accuracy and differences were calculated. The features of the high-fidelity DS-II, the technical specifications and the assessment procedures utilizing the playback software are described. Interobserver absolute differences (mean±SD) in measurements were 0.7±1.1/1.3±1.3 mmHg (SBP/DBP) with a mercury sphygmomanometer and 0.3±0.9/0.8±1.2 mmHg with the DS-II. The absolute DS-II mercury sphygmomanometer differences were 1.3±1.9/1.5±1.3 mmHg (SBP/DBP). The high-fidelity DS-II device presents satisfactory agreement with simultaneous measurements of blood pressure with a mercury sphygmomanometer. The device will be a valuable methodology for validating new blood pressure measurement technologies and devices.

Equipment for neonatal resuscitation in a middle-income country: a national survey in Vietnam.

PubMed

Trevisanuto, Daniele; Cavallin, Francesco; Arnolda, Gaston; Chien, Tran Dinh; Lincetto, Ornella; Xuan, Ngo Minh; Tien, Nguyen Viet; Hoi, Nguyen Thi Xuan; Moccia, Luciano

2016-08-20

Interventions to improve neonatal resuscitation are considered a priority for reducing neonatal mortality. In addition to training programs for health caregivers, the availability of adequate equipment in all delivery settings is crucial. In this study, we assessed the availability of equipment for neonatal resuscitation in a large sample of delivery rooms in Vietnam, exploring regional differences. In 2012, a structured questionnaire on 2011 neonatal resuscitation practice was sent to the heads of 187 health facilities, representing the three levels of hospital-based maternity services in eight administrative regions in Vietnam, allowing national and regional estimates to be calculated. Overall the response rate was an 85.7 % (160/187 hospitals). There was a limited availability of equipment considered as "essential" in the surveyed centres: stethoscopes (68.0 %; 95 % CI: 60.3-75.7), clock (50.3 %; 42.0-58.7), clothes (29.5 %; (22.0-36.9), head covering (12.3 %; 7.2-17.4). The percentage of centres equipped with polyethylene bags (2.2 %; 0.0-4.6), pulse oximeter (9.4 %; 5.2-13.6) and room air source (1.9 %; 0.1-3.6) was very low. Adequate equipment for neonatal resuscitation was not available in a considerable proportion of hospitals in Vietnam. This problem was more relevant in some regions. The assessment strategy used in this study could be useful for organizing the procurement and distribution of supplies and equipment in other low and/or middle resource settings.

Assessment of the swallowing function in older individuals referred to myocardial revascularization surgery.

PubMed

Dantas, Mara de Oliveira Rodrigues Luiz; Auler, José Otávio Costa; Andrade, Claudia Regina Furquim de

2010-01-01

Swallowing evaluation of older individuals with coronary disease referred to heart surgery. To identify the characteristics of the swallowing function in older individuals referred to myocardial revascularization surgery (MR), using an evaluating protocol composed by a water test, cervical auscultation and pulse oximetry. The Assessment Protocol for Dysphagia Risk through a Combined Swallowing test and Vital Signs monitoring was used (PADTC)--measurements of HR and SpO2 (heart rate and oxygen saturation), water swallowing test with 1, 3, 5, 10, 15 e 20 ml, measurement of respiratory rate and cervical auscultation. The electronic stethoscope was used to analyze the number of swallows, response time and swallowing sound classification. In the Research Group (RG) older individuals with heart disease who were referred to MR were included. In the Control Group (CG) healthy older individuals were included. 38 older individuals were evaluated in the RG (mean age 68 years). In the CG, 30 older individuals were evaluated (mean age 70 years). There was a significant difference for the swallowing response time in older individuals with heart disease who presented HR below 60: swallowing response was shorter for 3 ml, 10 ml, 15 ml e 20 ml. HR was lower for individuals with heart disease. No significant difference was found between the groups for the other analyzed parameters. Older individuals with heart disease presented differences in the swallowing function when compared to healthy older individuals. Older individuals with heart disease presented alterations in the temporal coordination between breathing and swallowing, thus indicating risk for dysphagia.

Utilizing lung sounds analysis for the evaluation of acute asthma in small children.

PubMed

Tinkelman, D G; Lutz, C; Conner, B

1991-09-01

One of the most difficult aspects of management of acute asthma in the small child is the clinician's inability to quantitate the response or lack of response to bronchodilator agents because of the inability of a child this age to perform objective lung measurements in the acute state. The present study was designed to evaluate bronchodilator responsiveness in children between 2 and 6 years of age with wheezing by means of a computerized lung sound analysis, computer digitized airway phonopneumonography. Children between ages 2 and 6 who were experiencing acute exacerbations of asthma were included in this study population. The 43 children were evaluated by physical examination, pulmonary function testing, if possible, by use of (spirometry or peak flow meter) and transmission of lung sounds to a computer using an electronic stethoscope to obtain a phonopneumograph with sound intensity level determinations during tidal breathing. A control group of 20 known asthmatic patients between the ages of 8 and 52 years who also presented to the office with acute asthma were evaluated similarly. In each of these individuals, a physical examination was followed by complete spirometry as well as computer digitized airway phonopneumonography recordings. Following initial measurements, all patients were treated with nebulized albuterol (0.25 mL in 2 mL of saline). Five minutes after completion of the nebulization all patients were reexamined and repeat pulmonary function tests were performed followed by CDAP recordings. In the study group of children, the mean pretreatment sound intensity level was 1,694 (range 557 to 4,950 SD +/- 745).(ABSTRACT TRUNCATED AT 250 WORDS)

The Relationship Between Crackle Characteristics and Airway Morphology in COPD.

PubMed

Bennett, Surussawadi; Bruton, Anne; Barney, Anna; Havelock, Tom; Bennett, Michael

2015-03-01

Crackles in COPD are believed to be generated by the re-opening of collapsed airways, which result from chronic inflammation, secretions, and loss of cartilaginous support through inflammation. However, it is unclear whether crackle characteristics can be used to identify COPD. This is the first study to examine the relationship between specific added lung sounds (crackles) and measurements of conductive airways and emphysema score obtained from high-resolution computed tomography (HRCT) in vivo in humans. A predictive relationship might permit the use of lung sounds as a biomarker for COPD. A convenience sample of 26 subjects was recruited into the study and consisted of 9 healthy non-smokers, 9 healthy smokers, and 8 subjects with mild or moderate COPD. Lung sound data were recorded using a digital stethoscope connected to a laptop computer. Airway diameter, emphysema score, and percentage of wall area were measured from HRCT scans. The analysis showed that there were no statistically significant differences in crackle characteristics (the number of crackles per breathing cycle and crackle 2-cycle duration) between the 3 subject groups. Both crackle 2-cycle duration and crackle number showed some significant correlation with airway parameters at some branch generations, but due to the large number of correlations performed, these were consistent with chance findings. Although there were some significant correlations between crackle characteristics and measurements of the conductive airways and emphysema score, the possibility that these correlations have occurred by chance cannot be ruled out. Therefore, this study provides no conclusive evidence that crackle characteristics are related to HRCT variables in COPD. Copyright © 2015 by Daedalus Enterprises.

Analysis of adventitious lung sounds originating from pulmonary tuberculosis.

PubMed

Becker, K W; Scheffer, C; Blanckenberg, M M; Diacon, A H

2013-01-01

Tuberculosis is a common and potentially deadly infectious disease, usually affecting the respiratory system and causing the sound properties of symptomatic infected lungs to differ from non-infected lungs. Auscultation is often ruled out as a reliable diagnostic technique for TB due to the random distribution of the infection and the varying severity of damage to the lungs. However, advancements in signal processing techniques for respiratory sounds can improve the potential of auscultation far beyond the capabilities of the conventional mechanical stethoscope. Though computer-based signal analysis of respiratory sounds has produced a significant body of research, there have not been any recent investigations into the computer-aided analysis of lung sounds associated with pulmonary Tuberculosis (TB), despite the severity of the disease in many countries. In this paper, respiratory sounds were recorded from 14 locations around the posterior and anterior chest walls of healthy volunteers and patients infected with pulmonary TB. The most significant signal features in both the time and frequency domains associated with the presence of TB, were identified by using the statistical overlap factor (SOF). These features were then employed to train a neural network to automatically classify the auscultation recordings into their respective healthy or TB-origin categories. The neural network yielded a diagnostic accuracy of 73%, but it is believed that automated filtering of the noise in the clinics, more training samples and perhaps other signal processing methods can improve the results of future studies. This work demonstrates the potential of computer-aided auscultation as an aid for the diagnosis and treatment of TB.

Feasibility of a focused ultrasound training programme for medical undergraduate students.

PubMed

Wong, Ivan; Jayatilleke, Thilina; Kendall, Richard; Atkinson, Paul

2011-03-01

Although ultrasound is a core skill for many clinical specialties, UK medical schools are not currently required to teach this skill. The College of Emergency Medicine (CEM) has championed the use of ultrasound to answer focused clinical questions in emergency settings. We have designed and piloted an ultrasound training course for undergraduate medical students addressing one important indication: ultrasound assessment of the abdominal aorta. Fourteen clinical students, who had no prior experience of using ultrasound, received focused ultrasound training in the form of didactic instruction, a short bedside practical workshop and self-directed learning over a 20-day period. At the end of this period, the students were assessed by a structured viva and an observed structured clinical examination (OSCE) used for accreditation by the CEM. The primary endpoint was the number of students who passed the assessment. The secondary endpoint was the accuracy of the students' anatomical measurements. Thirteen of the 14 (93%) students completed the training and assessment. Eight of the 13 (62%) students passed both the viva and OSCE, and were deemed to have achieved the CEM standard. The measurements by the competent students were not statistically different from those of experienced practitioners. We have shown for the first time that it is feasible to train inexperienced undergraduate students to scan the abdominal aorta to a professional standard using a focused training course. It is time for the medical education community to address whether focused ultrasound training should accompany traditional clinical skills, such as using a stethoscope, in UK medical school curricula. © Blackwell Publishing Ltd 2011.

Use of wind-up fetal Doppler versus Pinard for fetal heart rate intermittent monitoring in labour: a randomised clinical trial

PubMed Central

Byaruhanga, R; Bassani, D G; Jagau, A; Muwanguzi, P; Montgomery, A L; Lawn, J E

2015-01-01

Objectives In resource-poor settings, the standard of care to inform labour management is the partograph plus Pinard stethoscope for intermittent fetal heart rate (FHR) monitoring. We compared FHR monitoring in labour using a novel, robust wind-up handheld Doppler with the Pinard as a primary screening tool for abnormal FHR on perinatal outcomes. Design Prospective equally randomised clinical trial. Setting The labour and delivery unit of a teaching hospital in Kampala, Uganda. Participants Of the 2042 eligible antenatal women, 1971 women in active term labour, following uncomplicated pregnancies, were randomised to either the standard of care or not. Intervention Intermittent FHR monitoring using Doppler. Primary outcome measures Incidence of FHR abnormality detection, intrapartum stillbirth and neonatal mortality prior to discharge. Results Age, parity, gestational age, mode of delivery and newborn weight were similar between study groups. In the Doppler group, there was a significantly higher rate of FHR abnormalities detected (incidence rate ratio (IRR)=1.61, 95% CI 1.13 to 2.30). However, in this group, there were also higher though not statistically significant rates of intrapartum stillbirths (IRR=3.94, 0.44 to 35.24) and neonatal deaths (IRR=1.38, 0.44 to 4.34). Conclusions Routine monitoring with a handheld Doppler increased the identification of FHR abnormalities in labour; however, our trial did not find evidence that this leads to a decrease in the incidence of intrapartum stillbirth or neonatal death. Trial registration number Clinical Trails.gov (1000031587). PMID:25636792

Use of wind-up fetal Doppler versus Pinard for fetal heart rate intermittent monitoring in labour: a randomised clinical trial.

PubMed

Byaruhanga, R; Bassani, D G; Jagau, A; Muwanguzi, P; Montgomery, A L; Lawn, J E

2015-01-30

In resource-poor settings, the standard of care to inform labour management is the partograph plus Pinard stethoscope for intermittent fetal heart rate (FHR) monitoring. We compared FHR monitoring in labour using a novel, robust wind-up handheld Doppler with the Pinard as a primary screening tool for abnormal FHR on perinatal outcomes. Prospective equally randomised clinical trial. The labour and delivery unit of a teaching hospital in Kampala, Uganda. Of the 2042 eligible antenatal women, 1971 women in active term labour, following uncomplicated pregnancies, were randomised to either the standard of care or not. Intermittent FHR monitoring using Doppler. Incidence of FHR abnormality detection, intrapartum stillbirth and neonatal mortality prior to discharge. Age, parity, gestational age, mode of delivery and newborn weight were similar between study groups. In the Doppler group, there was a significantly higher rate of FHR abnormalities detected (incidence rate ratio (IRR)=1.61, 95% CI 1.13 to 2.30). However, in this group, there were also higher though not statistically significant rates of intrapartum stillbirths (IRR=3.94, 0.44 to 35.24) and neonatal deaths (IRR=1.38, 0.44 to 4.34). Routine monitoring with a handheld Doppler increased the identification of FHR abnormalities in labour; however, our trial did not find evidence that this leads to a decrease in the incidence of intrapartum stillbirth or neonatal death. Clinical Trails.gov (1000031587). Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Distribution of craniomandibular disorders, occlusal factors and oral parafunctions in a paediatric population.

PubMed

Corvo, G; Tartaro, G; Giudice, A; Diomajuta, A

2003-06-01

The aim of this work was to gather clinical data on craniomandibular (CMD)/temporomandibular joint (TMJ) disorders in a paediatric population. The clinical study population comprised patients with TMJ disorders who were being treated in the orthognathic ambulatory clinic of the University of Naples, where an instrumental and clinical study was performed. Data were recorded for extra and intraoral findings, Angles classification and malocclusions. Radiographic examinations were carried out. Study models were fabricated for evaluation. TMJs were assessed by palpation as well as masseter, temporal, suprahyoid, sternocleidomastoid, suboccipital, paravertebral and trapezius muscles to evaluate any possible pain. Auscultation of the TMJ was used to determine presence of articular sounds and their type (cracks, crunches, clicks) by the use of a stethoscope. Pain localisation was evaluated according to these movements taking into account site, intensity, frequency, and duration. Episodes of headache were recorded according to its intensity (mild, moderate, intense), frequency (daily, weekly, monthly), site (top of the head, occiput, temple, frontal, overorbital region, back of the head) and the duration of the episodes (in minutes, hours or whether constant). A substantial number of the 106 patients included in the study showed a malocclusion with prevalence in Angles Class II cases. Bruxism, onychophagy, TMJ pain, headache, mouth opening partial inability, mastication difficulty and articular sound were the most representative symptoms. The identification and recognition of factors, such as malocclusions and parafunctions, are considered fundamental to early diagnosis of TMJ problems, which is the most useful way to avoid a dysfunctional state of the stomatognathic system.

Medical informatics--an Australian perspective.

PubMed

Hannan, T

1991-06-01

Computers, like the X-ray and stethoscope can be seen as clinical tools, that provide physicians with improved expertise in solving patient management problems. As tools they enable us to extend our clinical information base, and they also provide facilities that improve the delivery of the health care we provide. Automation (computerisation) in the health domain will cause the computer to become a more integral part of health care management and delivery before the start of the next century. To understand how the computer assists those who deliver and manage health care, it is important to be aware of its functional capabilities and how we can use them in medical practice. The rapid technological advances in computers over the last two decades has had both beneficial and counterproductive effects on the implementation of effective computer applications in the delivery of health care. For example, in the 1990s the computer hobbyist is able to make an investment of less than $10,000 on computer hardware that will match or exceed the technological capacities of machines of the 1960s. These rapid technological advances, which have produced a quantum leap in our ability to store and process information, have tended to make us overlook the need for effective computer programmes which will meet the needs of patient care. As the 1990s begin, those delivering health care (eg, physicians, nurses, pharmacists, administrators ...) need to become more involved in directing the effective implementation of computer applications that will provide the tools for improved information management, knowledge processing, and ultimately better patient care.

Preclinical medical students' understandings of academic and medical professionalism: visual analysis of mind maps.

PubMed

Janczukowicz, Janusz; Rees, Charlotte E

2017-08-18

Several studies have begun to explore medical students' understandings of professionalism generally and medical professionalism specifically. Despite espoused relationships between academic (AP) and medical professionalism (MP), previous research has not yet investigated students' conceptualisations of AP and MP and the relationships between the two. The current study, based on innovative visual analysis of mind maps, therefore aims to contribute to the developing literature on how professionalism is understood. We performed a multilayered analysis of 98 mind maps from 262 first-year medical students, including analysing textual and graphical elements of AP, MP and the relationships between AP and MP. The most common textual attributes of AP were learning, lifestyle and personality, while attributes of MP were knowledge, ethics and patient-doctor relations. Images of books, academic caps and teachers were used most often to represent AP, while images of the stethoscope, doctor and red cross were used to symbolise MP. While AP-MP relations were sometimes indicated through co-occurring text, visual connections and higher-order visual metaphors, many students struggled to articulate the relationships between AP and MP. While the mind maps' textual attributes shared similarities with those found in previous research, suggesting the universality of some professionalism attributes, our study provides new insights into students' conceptualisations of AP, MP and AP-MP relationships. We encourage medical educators to help students develop their understandings of AP, MP and AP-MP relationships, plus consider the feasibility and value of mind maps as a source of visual data for medical education research. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Effect of spontaneous saliva swallowing on short-term heart rate variability (HRV) and reliability of HRV analysis.

PubMed

Yildiz, Metin; Doma, Serian

2017-09-26

The effects of effortful swallowing and solid meal ingestions on heart rate variability (HRV) have been examined previously. The effects of spontaneous saliva swallowing on short-term HRV and reliability of HRV analysis have not been studied before. The effect of saliva swallowing on HRV analyses parameters [meanRRI, SDNN (standard deviation of normal-to-normal), LF (low frequency), HF (high frequency) powers, LH/HF] and the reliability of LF and HF powers were investigated by frequency, time-frequency and intraclass correlation coefficient (ICC) analyses. Electrocardiogram and swallowing signal that obtained from an electronic stethoscope placed on the necks of subjects were recorded simultaneously from 30 healthy and young volunteers in sitting position during 15 min. Spontaneous swallowing has been shown to significantly alter some HRV parameters (SDNN, LF power and LF/HF ratio). Time-frequency analysis results showed that the contribution of saliva swallowing to LF (1-58%) and HF (2-42%) powers could change significantly depending on the number of swallowing. The ICC of the LF and HF powers for the successive 5-min signal segments were found 0·89, 0·92, respectively. These values decreased to 0·73 and 0·90 in the subjects with more swallowing rate. When the analyses were made for 2-min signal periods, these values decreased to 0·63 and 0·67. We concluded that spontaneous saliva swallowing can change HRV parameters. We have also seen that changes in swallowing rate and use of short signal segments may reduce the reliability of HRV analyses. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

Mobile learning devices in the workplace: 'as much a part of the junior doctors' kit as a stethoscope'?

PubMed

Dimond, Rebecca; Bullock, Alison; Lovatt, Joseph; Stacey, Mark

2016-08-17

Smartphones are ubiquitous and commonly used as a learning and information resource. They have potential to revolutionize medical education and medical practice. The iDoc project provides a medical textbook smartphone app to newly-qualified doctors working in Wales. The project was designed to assist doctors in their transition from medical school to workplace, a period associated with high levels of cognitive demand and stress. Newly qualified doctors submitted case reports (n = 293) which detail specific instances of how the textbook app was used. Case reports were submitted via a structured online form (using Bristol Online Surveys - BOS) which gave participants headings to elicit a description of: the setting/context; the problem/issue addressed; what happened; any obstacles involved; and their reflections on the event. Case reports were categorised by the purpose of use, and by elements of the quality improvement framework (IoM 2001). They were then analysed thematically to identify challenges of use. Analysis of the case reports revealed how smartphones are a viable tool to address clinical questions and support mobile learning. They contribute to novice doctors' provision of safe, effective, timely, efficient and patient-centred care. The case reports also revealed considerable challenges for doctors using mobile technology within the workplace. Participants reported concern that using a mobile phone in front of patients and staff might appear unprofessional. Mobile phones blur boundaries between the public and private, and the personal and professional. In contrast to using a mobile as a communication device, using a smartphone as an information resource in the workplace requires different rituals. Uncertain etiquette of mobile use may reduce the capacity of smartphone technology to improve the learning experience of newly qualified doctors.

Determining the utility and durability of medical equipment donated to a rural clinic in a low-income country.

PubMed

Bauserman, Melissa; Hailey, Claire; Gado, Justin; Lokangaka, Adrien; Williams, Jessica; Richards-Kortum, Rebecca; Tshefu, Antoinette; Bose, Carl

2015-07-01

Health centers in low-income countries often depend on donations to provide appropriate diagnostic equipment. However, donations are sometimes made without an understanding of the recipient's needs, practical constraints or sustainability of supplies. We donated a set of physical diagnostic equipment, non-invasive instrument tests and laboratory supplies to a rural health center in the Democratic Republic of Congo. We collected information on the usage and durability of equipment and supplies for each patient encounter over a 1-year period. We recorded 913 patient encounters. The most commonly used physical diagnostic equipment were the stethoscope (98.9%; 903/913), thermometer (81.7%; 746/913), adult scale (81.4%; 744/913), stop watch (62.6%; 572/913), adult sphygmomanometer (55.8%; 510/913), infant scale (24.9%; 228/913), measuring tape (24.3%; 222/913) and fetoscope (23.8%; 218/913). The most commonly used laboratory tests were the blood smear for malaria (53.7%; 491/913), hematocrit (23.5%; 215/913), urinalysis (20.1%; 184/913) and sputum stain for TB (13.3%; 122/913). With the exception of a penlight and solar lantern, all equipment remained functional. This study adds valuable information about the utility and durability of equipment supplied to a health center in the Democratic Republic of Congo. Our results might aid in determining the appropriateness of donated medical equipment in similar settings. The selection of donated goods should be made with knowledge of the context in which it will be used, and utilization should be monitored. © The Author 2014. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Care Offered by an Information-Rich Pediatric Acute Illness Connected Care Model.

PubMed

McConnochie, Kenneth M; Wood, Nancy E; Alarie, Carol; Ronis, Sarah

2016-06-01

Prevailing regulatory and financing issues constrain dissemination of connected care despite evidence supporting acceptability, effectiveness, and efficiency. In this analysis we describe care provided over a 12-year period by Health-e-Access, an evidence-based, information-rich, connected care model designed to serve children with acute illness. We demonstrate the broad clinical capacity of this care model and key components imparting this capacity. Since 2001, Health-e-Access has been used in childcare, elementary schools, neighborhood after-hours sites, and a school for children with severe disabilities in Rochester, NY. With Health-e-Access, videoconference (preferably) or telephone enables parent, patient, and provider engagement. Technology includes the capacity for acquisition and exchange of a broad range of clinical observations, qualifying Health-e-Access as an information-rich model and differentiating it from multiple other connected care models commonly labeled telemedicine. Primary diagnoses recorded for completed visits were classified according to resources (technology, personnel, examination type) required to complete encounters appropriately. Among 13,812 Health-e-Access visits initiated through June 2013, 98.2% were completed. Capacity for ear-nose-throat examination and close inspection of eye and skin were sufficient to identify positive findings supporting 95.2% of primary diagnoses. Videoconference and stethoscope were considered essential for observations required to rule out serious conditions often presenting in similar fashion to these 95%. Health-e-Access included technology essential for establishing diagnoses, ruling out more serious conditions, and identifying problems beyond its scope. Regulations enabling and financing incentivizing replication of similar connected care models would benefit families and communities substantially. Observations challenge regulatory bodies and payers to support connected health services of comparable value.

Brief group training of medical students in focused cardiac ultrasound may improve diagnostic accuracy of physical examination.

PubMed

Stokke, Thomas M; Ruddox, Vidar; Sarvari, Sebastian I; Otterstad, Jan E; Aune, Erlend; Edvardsen, Thor

2014-11-01

Physical examination and auscultation can be challenging for medical students. The aim of this study was to investigate whether a brief session of group training in focused cardiac ultrasound (FCU) with a pocket-sized device would allow medical students to improve their ability to detect clinically relevant cardiac lesions at the bedside. Twenty-one medical students in their clinical curriculum completed 4 hours of FCU training in groups. The students examined patients referred for echocardiography with emphasis on auscultation, followed by FCU. Findings from physical examination and FCU were compared with those from standard echocardiography performed and analyzed by cardiologists. In total, 72 patients were included in the study, and 110 examinations were performed. With a stethoscope, sensitivity to detect clinically relevant (moderate or greater) valvular disease was 29% for mitral regurgitation, 33% for aortic regurgitation, and 67% for aortic stenosis. FCU improved sensitivity to detect mitral regurgitation (69%, P < .001). However, sensitivity to detect aortic regurgitation (43%) and aortic stenosis (70%) did not improve significantly. Specificity was ≥89% for all valvular diagnoses by both methods. For nonvalvular diagnoses, FCU's sensitivity to detect moderate or greater left ventricular dysfunction (90%) was excellent, detection of right ventricular dysfunction (79%) was good, while detection of dilated left atrium (53%), dilated right atrium (49%), pericardial effusion (40%), and dilated aortic root (25%) was less accurate. Specificity varied from 57% to 94%. After brief group training in FCU, medical students could detect mitral regurgitation significantly better compared with physical examination, whereas detection of aortic regurgitation and aortic stenosis did not improve. Left ventricular dysfunction was detected with high sensitivity. More extensive training is advised. Copyright © 2014 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Validation of the A&D UM-211 device for office blood pressure measurement according to the European Society of Hypertension International Protocol revision 2010.

PubMed

Fania, Claudio; Albertini, Federica; Palatini, Paolo

2017-10-01

The aim of this study was to define the accuracy of UM-211, an automated oscillometric device for office use coupled to several cuffs for different arm sizes, according to the International Protocol of the European Society of Hypertension. The validation was performed in 33 individuals. Their mean age was 59.6±12.9 years, systolic blood pressure (BP) was 144.3±21.5 mmHg (range: 96-184 mmHg), diastolic BP was 86.8±18.5 mmHg (range: 48-124 mmHg), and arm circumference was 30.2±4.3 cm (range: 23-39 cm). Four sequential readings were taken by observers 1 and 2 using a double-headed stethoscope and a mercury sphygmomanometer, whereas three BP readings were taken by the supervisor using the test instrument. The differences between the readings provided by the device and the mean observer measurements were calculated. Therefore, each device measurement was compared with the previous and the next mean observer measurement. The validation results fulfilled all the 2010 European Society of Hypertension revision Protocol criteria for the general population and passed all validation grades. On average, the device overestimated systolic BP by 1.7±2.4 mmHg and diastolic BP by 1.7±2.5 mmHg. These data show that the UM-211 device coupled to several cuffs for different ranges of arm circumference met the requirements for validation according to the International Protocol and can be recommended for clinical use in the adult population. However, these results mainly apply to the use of the 22-32 and the 31-45 cm cuffs.

Carotid artery ultrasonographic assessment in patients from the Fremantle Diabetes Study Phase II with carotid bruits detected by electronic auscultation.

PubMed

Knapp, Arthur; Cetrullo, Violetta; Sillars, Brett A; Lenzo, Nat; Davis, Wendy A; Davis, Timothy M E

2014-09-01

Electronic auscultation appears superior to acoustic auscultation for identifying hemodynamic abnormalities. The aim of this study was to determine whether carotid bruits detected by electronic stethoscope in patients with diabetes are associated with stenoses and increased carotid intima-medial thickness (CIMT). Fifty Fremantle Diabetes Study patients (mean±SD age, 73.7±10.0 years; 38.0% males) with a bruit found by electronic auscultation and 50 age- and sex-matched patients with normal carotid sounds were studied. The degree of stenosis and CIMT were assessed from duplex ultrasonography. Patients with a bruit were more likely to have stenosis of ≥50% and CIMT of >1.0 mm than those without (odds ratios [95% confidence intervals]=14.0 [1.8-106.5] and 5.3 [1.8-15.3], respectively; both P=0.001). For the six patients with stenosis of ≥70%, five had a bruit, and one (with a known total occlusion) did not (odds ratio=5.0 [0.6-42.8]; P=0.22). The sensitivity and specificity of carotid bruit for stenoses of ≥50% were 88% and 58%, respectively; respective values for stenoses of ≥70% were 83% and 52%. The equivalent negative predictive values were 96% and 98%, and positive predictive values were 30% and 10%, respectively. Electronic recording of carotid sounds for later interpretation is convenient and reliable. Most patients with stenoses had an overlying bruit. Most bruits were false positives, but ultrasonography is justified to document extent of disease; CIMT measurement will identify increased vascular risk in most of these patients. The absence of a bruit was rarely a false-negative finding, suggesting that these patients can usually be reassured that they do not have hemodynamically important stenosis.

Stethoscope vs. ultrasound probe - which is more reliable in children with suspected pneumonia?

PubMed

Lovrenski, Jovan; Petrović, Slobodanka; Balj-Barbir, Svetlana; Jokić, Radoica; Vilotijević-Dautović, Gordana

2016-05-01

To compare lung ultrasound (LUS) with auscultation findings in children with clinical suspicion of pneumonia. A prospective study including 95 patients (age: from 2 months to 17.5 years; mean age: 5.1 y, SD 4.5 y) with referral diagnosis of suspected pneumonia. In all patients LUS and auscultatory examinations were performed within an hour. These findings were compared separately in each hemithorax. The radiologist performing LUS was blinded to the patient's clinical information. Positive auscultatory findings included: crackles and/or abnormal breath sounds (decreased, asymmetric, absent, or bronchial). For LUS examinations a combined transthoracic - transabdominal approach was used. A pneumonia-positive LUS finding included subpleural consolidation with air-bronchogram, or an adjacent area of interstitial edema. For each subpleural consolidation the cranio-caudal (CC) diameter was measured, and 95% confidence intervals (CI) of the sizes of subpleural consolidations for positive and negative auscultatory findings were compared. The p-value between LUS and auscultation was calculated using McNemar's test. LUS and auscultation showed pneumonia-positive findings in 98 and 64 hemithoraces, i.e. in 67 and 45 patients respectively. In positive auscultatory findings the CI for CC diameters of subpleural consolidations ranged from 32.46 to 54.14 mm, and in negative auscultatory findings the CI was between 16.52 and 29.83 mm, which showed a statistically significant difference. McNemar's test showed a statistically significant difference between LUS and auscultation. LUS showed positive findings in more hemithoraces than auscultation in children with suspected pneumonia. A cranio-caudal size of subpleural consolidation of less than 30 mm significantly reduces the possibility of auscultatory detection. Copyright © 2016 by Academy of Sciences and Arts of Bosnia and Herzegovina.

Detection of Respiratory Adverse Events in Pediatric Dental Patients Sedated With 0.75mg/Kg of Midazolam and Oxygen by Continuous Pretracheal Auscultation: A Prospective Randomized Controlled Trial.

PubMed

Somri, Mostafa; Matter, Ibrahim; Hadjittofi, Christopher; Hoash, Naser; Moaddi, Bian; Kharouba, Johnny; Parisinos, Constantinos A; Peretz, Benjamin

Sedation is becoming more commonplace for pediatric patients undergoing minor procedures. Fortunately, electronic monitors have contributed to a reduction in the associated respiratory adverse events (RAEs). To test the hypothesis that adding the pretracheal stethoscope (PTS) to standard monitoring methods (SMMs) may improve RAE detection in sedated pediatric dental patients, the frequency of RAEs detected by SMMs (i.e. visual observation, capnography, and pulse oximetry) was compared to that detected by SMMs alongside continuous PTS auscultation. A prospective, randomised, controlled trial was performed with 100 pediatric patient participants of ASA≤2, who were scheduled to receive dental treatment under 0.75 mg/kg and oxygen. Patients were randomised into Groups A (n=50; SMMs) and B (n=50; SMMs+PTS). Inclusion criteria were behavioral management problems and intolerance to dental treatment despite behavioral management techniques or nitrous oxide administration. Exclusion criteria were high-risk conditions for RAEs, altered mental status, gastrointestinal disorders, parental refusal of conscious sedation and failure of previous conscious sedation. An anesthesist was present throughout the dental treatments. RAEs were detected in 10 (20%) and 22(44%) Group A and B patients respectively (p=0.01). The majority of RAEs within Group B were detected by PTS auscultation (n=19). Capnography produced 13 and 15 false-positive results in Groups A and B respectively, whereas the PTS produced 4(8%) false-positive results in Group B (p=0.009). PTS was found to be useful for detecting RAEs during pediatric dental sedation with 0.75mg/kg midazolam and oxygen, in the presence of an anesthesist.

Economic analysis of bedside ultrasonography (US) implementation in an Internal Medicine department.

PubMed

Testa, Americo; Francesconi, Andrea; Giannuzzi, Rosangela; Berardi, Silvia; Sbraccia, Paolo

2015-12-01

The economic crisis, the growing healthcare demand, and Defensive Medicine wastefulness, strongly recommend the restructuring of the entire medical network. New health technology, such as bedside ultrasonography, might successfully integrate the clinical approach optimizing the use of limited resources, especially in a person-oriented vision of medicine. Bedside ultrasonography is a safe and reliable technique, with worldwide expanding employment in various clinical settings, being considered as "the stethoscope of the 21st century". However, at present, bedside ultrasonography lacks economic analysis. We performed a Cost-Benefit Analysis "ex ante", with a break-even point computing, of bedside ultrasonography implementation in an Internal Medicine department in the mid-term. Number and kind estimation of bedside ultrasonographic studies were obtained by a retrospective study, whose data results were applied to the next 3-year period (foresight study). All 1980 foreseen bedside examinations, with prevailing multiorgan ultrasonographic studies, were considered to calculate direct and indirect costs, while specific and generic revenues were considered only after the first semester. Physician professional training, equipment purchase and working time represented the main fixed and variable cost items. DRG increase/appropriateness, hospitalization stay shortening and reduction of traditional ultrasonography examination requests mainly impacted on calculated revenues. The break-even point, i.e. the volume of activity at which revenues exactly equal total incurred costs, was calculated to be 734 US examinations, corresponding to € 81,998 and the time considered necessary to reach it resulting 406 days. Our economic analysis clearly shows that bedside ultrasonography implementation in clinical daily management of an Internal Medicine department can produce consistent savings, or economic profit according to managerial choices (i.e., considering public or private targets), other than evident medical benefits.

A randomised, simulated study assessing auscultation of heart rate at birth.

PubMed

Voogdt, Kevin G J A; Morrison, Allison C; Wood, Fiona E; van Elburg, Ruurd M; Wyllie, Jonathan P

2010-08-01

Heart rate is a primary clinical indicator directing newborn resuscitation. The time taken to assess the heart rate by auscultation in relation to accuracy during newborn resuscitation is not known. To assess both the accuracy and time taken to assess heart rate by stethoscope in simulated resuscitation scenarios. The VitalSim((c)) manikin (Laerdal Medical, Stavanger, Norway) was used in this randomised, single blind study. Four heart rate settings (0, 40, 80, 120 beats per minute (bpm)) were randomly assigned. Participants assessed them by auscultation in three different scenarios. The first scenario was to assess the actual heart rate at birth. In the second scenario, heart rate was assessed during ventilation and assigned to standard ranges (<60, 60-100, >100bpm). In the third scenario, heart rate was assessed after three cycles of compressions and ventilation and assigned to standard ranges. In total 61 midwives, nurses and doctors performed 183 assessments. Mean time to estimate heart rate for scenarios 1, 2 and 3 was: 17.0, 9.8 and 7.8s respectively. Heart rate assessments were inaccurate in 31% (scenario 1), 28% (scenarios 2) and 26% (scenario 3). There was a trend for assessors who were accurate to be quicker and this achieved significance in scenario 2 (p<0.02). Inaccurate assessment would have made a difference to management in 28% of all cases. Mean time to estimate heart rate for the scenarios varied between 7.8 and 17.0s. Twenty-eight percent of all heart rate assessments would have prompted incorrect management during resuscitation or stabilization. Of incorrect assessments, 73% were overestimations. Further research is required to develop a rapid and accurate method for determining heart rate during newborn resuscitation. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

International perception of lung sounds: a comparison of classification across some European borders

PubMed Central

Aviles-Solis, Juan Carlos; Vanbelle, Sophie; Halvorsen, Peder A; Francis, Nick; Cals, Jochen W L; Andreeva, Elena A; Marques, Alda; Piirilä, Päivi; Pasterkamp, Hans; Melbye, Hasse

2017-01-01

Introduction Lung auscultation is helpful in the diagnosis of lung and heart diseases; however, the diagnostic value of lung sounds may be questioned due to interobserver variation. This situation may also impair clinical research in this area to generate evidence-based knowledge about the role that chest auscultation has in a modern clinical setting. The recording and visual display of lung sounds is a method that is both repeatable and feasible to use in large samples, and the aim of this study was to evaluate interobserver agreement using this method. Methods With a microphone in a stethoscope tube, we collected digital recordings of lung sounds from six sites on the chest surface in 20 subjects aged 40 years or older with and without lung and heart diseases. A total of 120 recordings and their spectrograms were independently classified by 28 observers from seven different countries. We employed absolute agreement and kappa coefficients to explore interobserver agreement in classifying crackles and wheezes within and between subgroups of four observers. Results When evaluating agreement on crackles (inspiratory or expiratory) in each subgroup, observers agreed on between 65% and 87% of the cases. Conger’s kappa ranged from 0.20 to 0.58 and four out of seven groups reached a kappa of ≥0.49. In the classification of wheezes, we observed a probability of agreement between 69% and 99.6% and kappa values from 0.09 to 0.97. Four out of seven groups reached a kappa ≥0.62. Conclusions The kappa values we observed in our study ranged widely but, when addressing its limitations, we find the method of recording and presenting lung sounds with spectrograms sufficient for both clinic and research. Standardisation of terminology across countries would improve international communication on lung auscultation findings. PMID:29435344

Frequency and number of ultrasound lung rockets (B-lines) using a regionally based lung ultrasound examination named vet BLUE (veterinary bedside lung ultrasound exam) in dogs with radiographically normal lung findings.

PubMed

Lisciandro, Gregory R; Fosgate, Geoffrey T; Fulton, Robert M

2014-01-01

Lung ultrasound is superior to lung auscultation and supine chest radiography for many respiratory conditions in human patients. Ultrasound diagnoses are based on easily learned patterns of sonographic findings and artifacts in standardized images. By applying the wet lung (ultrasound lung rockets or B-lines, representing interstitial edema) versus dry lung (A-lines with a glide sign) concept many respiratory conditions can be diagnosed or excluded. The ultrasound probe can be used as a visual stethoscope for the evaluation of human lungs because dry artifacts (A-lines with a glide sign) predominate over wet artifacts (ultrasound lung rockets or B-lines). However, the frequency and number of wet lung ultrasound artifacts in dogs with radiographically normal lungs is unknown. Thus, the primary objective was to determine the baseline frequency and number of ultrasound lung rockets in dogs without clinical signs of respiratory disease and with radiographically normal lung findings using an 8-view novel regionally based lung ultrasound examination called Vet BLUE. Frequency of ultrasound lung rockets were statistically compared based on signalment, body condition score, investigator, and reasons for radiography. Ten left-sided heart failure dogs were similarly enrolled. Overall frequency of ultrasound lung rockets was 11% (95% confidence interval, 6-19%) in dogs without respiratory disease versus 100% (95% confidence interval, 74-100%) in those with left-sided heart failure. The low frequency and number of ultrasound lung rockets observed in dogs without respiratory disease and with radiographically normal lungs suggests that Vet BLUE will be clinically useful for the identification of canine respiratory conditions. © 2014 American College of Veterinary Radiology.

Total intravenous anesthesia (TIVA) in an infant with Werdnig-Hoffmann disease. Case report.

PubMed

de Resende, Marco Antonio Cardoso; da Silva, Elizabeth Vaz; Nascimento, Osvaldo José Moreira; Gemal, Alberto Esteves; Quintanilha, Giseli; Vasconcelos, Eliana Maria

2010-01-01

Werdnig-Hoffmann disease is the most common cause of hypotonia in infants and its prognosis is worse if it is present shortly after delivery. Symmetrical muscular weakness, areflexia, and fasciculations of the tongue are characteristic. The majority of the infants die before two years of age as a consequence of respiratory failure. The present report presents a case in which total intravenous anesthesia was used. This is a 1 year old white female weighing 10 kg, physical status ASA III, with Werdnig-Hoffmann disease diagnosed at two months of age. The patient was a candidate for open gastrostomy, fundus gastroplication, and tracheostomy. After venoclysis, the patient was monitored with cardioscope, non-invasive blood pressure, pulse oximeter, precordial stethoscope, and rectal temperature. She was oxygenated and, after bolus administration of atropine (0.3 mg), boluses of remifentanil (20 microg) and propofol (30 mg) were administered for anesthetic induction. After tracheal intubation, she was ventilated with manual controlled system without CO(2) absorber, Baraka (Mapleson D system), FGF of 4 L.min(-1), and FiO(2) 0.5 (O(2)/N(2)O). Anesthesia was maintained with continuous manual infusion of propofol, 250 microg x kg(-1) x min(-1), and remifentanil, 0.3 microg x kg(-1) x min(-1). The surgery lasted 150 minutes. The patient regained consciousness 8 minutes after the end of the infusion, ventilating spontaneously. Two hours later, she was transferred to the pediatric unit, being discharged from the hospital on the fourth postoperative day. The choice of anesthetic technique gives priority to the safety associated with the familiarity of handling available drugs. In children with neuromuscular diseases, due to the extremely short duration, total intravenous anesthesia with remifentanil and propofol in infusion systems can have a favorable influence on disease evolution.

Computerized respiratory sounds: a comparison between patients with stable and exacerbated COPD.

PubMed

Jácome, Cristina; Oliveira, Ana; Marques, Alda

2017-09-01

Diagnosis of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is often challenging as it relies on patients' clinical presentation. Computerized respiratory sounds (CRS), namely crackles and wheezes, may have the potential to contribute for the objective diagnosis/monitoring of an AECOPD. This study explored if CRS differ during stable and exacerbation periods in patients with COPD. 13 patients with stable COPD and 14 with AECOPD were enrolled. CRS were recorded simultaneously at trachea, anterior, lateral and posterior chest locations using seven stethoscopes. Airflow (0.4-0.6l/s) was recorded with a pneumotachograph. Breathing phases were detected using airflow signals; crackles and wheezes with validated algorithms. At trachea, anterior and lateral chest, no significant differences were found between the two groups in the number of inspiratory/expiratory crackles or inspiratory wheeze occupation rate. At posterior chest, the number of crackles (median 2.97-3.17 vs. 0.83-1.2, P < 0.001) and wheeze occupation rate (median 3.28%-3.8% vs. 1.12%-1.77%, P = 0.014-0.016) during both inspiration and expiration were significantly higher in patients with AECOPD than in stable patients. During expiration, wheeze occupation rate was also significantly higher in patients with AECOPD at trachea (median 3.12% vs. 0.79%, P < 0.001) and anterior chest (median 3.55% vs. 1.28%, P < 0.001). Crackles and wheezes are more frequent in patients with AECOPD than in stable patients, particularly at posterior chest. These findings suggest that these CRS can contribute to the objective diagnosis/monitoring of AECOPD, which is especially valuable considering that they can be obtained by integrating computerized techniques with pulmonary auscultation, a noninvasive method that is a component of patients' physical examination. © 2015 John Wiley & Sons Ltd.

Evaluation of a Computer-aided Lung Auscultation System for Diagnosis of Bovine Respiratory Disease in Feedlot Cattle.

PubMed

Mang, A V; Buczinski, S; Booker, C W; Timsit, E

2015-01-01

A computer-aided lung auscultation (CALA) system was recently developed to diagnose bovine respiratory disease (BRD) in feedlot cattle. To determine, in a case-control study, the level of agreement between CALA and veterinary lung auscultation and to evaluate the sensitivity (Se) and specificity (Sp) of CALA to diagnose BRD in feedlot cattle. A total of 561 Angus cross-steers (initial body weight = 246 ± 45 kg) were observed during the first 50 day after entry to a feedlot. Case-control study. Steers with visual signs of BRD identified by pen checkers were examined by a veterinarian, including lung auscultation using a conventional stethoscope and CALA that produced a lung score from 1 (normal) to 5 (chronic). For each steer examined for BRD, 1 apparently healthy steer was selected as control and similarly examined. Agreement between CALA and veterinary auscultation was assessed by kappa statistic. CALA's Se and Sp were estimated using Bayesian latent class analysis. Of the 561 steers, 35 were identified with visual signs of BRD and 35 were selected as controls. Comparison of veterinary auscultation and CALA (using a CALA score ≥2 as a cut off) revealed a substantial agreement (kappa = 0.77). Using latent class analysis, CALA had a relatively high Se (92.9%; 95% credible interval [CI] = 0.71-0.99) and Sp (89.6%; 95% CI = 0.64-0.99) for diagnosing BRD compared with pen checking. CALA had good diagnostic accuracy (albeit with a relatively wide CI). Its use in feedlots could increase the proportion of cattle accurately diagnosed with BRD. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Developing a Reference of Normal Lung Sounds in Healthy Peruvian Children

PubMed Central

Ellington, Laura E.; Emmanouilidou, Dimitra; Elhilali, Mounya; Gilman, Robert H.; Tielsch, James M.; Chavez, Miguel A.; Marin-Concha, Julio; Figueroa, Dante; West, James

2018-01-01

Purpose Lung auscultation has long been a standard of care for the diagnosis of respiratory diseases. Recent advances in electronic auscultation and signal processing have yet to find clinical acceptance; however, computerized lung sound analysis may be ideal for pediatric populations in settings, where skilled healthcare providers are commonly unavailable. We described features of normal lung sounds in young children using a novel signal processing approach to lay a foundation for identifying pathologic respiratory sounds. Methods 186 healthy children with normal pulmonary exams and without respiratory complaints were enrolled at a tertiary care hospital in Lima, Peru. Lung sounds were recorded at eight thoracic sites using a digital stethoscope. 151 (81 %) of the recordings were eligible for further analysis. Heavy-crying segments were automatically rejected and features extracted from spectral and temporal signal representations contributed to profiling of lung sounds. Results Mean age, height, and weight among study participants were 2.2 years (SD 1.4), 84.7 cm (SD 13.2), and 12.0 kg (SD 3.6), respectively; and, 47 % were boys. We identified ten distinct spectral and spectro-temporal signal parameters and most demonstrated linear relationships with age, height, and weight, while no differences with genders were noted. Older children had a faster decaying spectrum than younger ones. Features like spectral peak width, lower-frequency Mel-frequency cepstral coefficients, and spectro-temporal modulations also showed variations with recording site. Conclusions Lung sound extracted features varied significantly with child characteristics and lung site. A comparison with adult studies revealed differences in the extracted features for children. While sound-reduction techniques will improve analysis, we offer a novel, reproducible tool for sound analysis in real-world environments. PMID:24943262

A mobile platform for automated screening of asthma and chronic obstructive pulmonary disease.

PubMed

Chamberlain, Daniel B; Kodgule, Rahul; Fletcher, Richard Ribon

2016-08-01

Chronic Obstructive Pulmonary Disease (COPD) and asthma each represent a large proportion of the global disease burden; COPD is the third leading cause of death worldwide and asthma is one of the most prevalent chronic diseases, afflicting over 300 million people. Much of this burden is concentrated in the developing world, where patients lack access to physicians trained in the diagnosis of pulmonary disease. As a result, these patients experience high rates of underdiagnosis and misdiagnosis. To address this need, we present a mobile platform capable of screening for Asthma and COPD. Our solution is based on a mobile smart phone and consists of an electronic stethoscope, a peak flow meter application, and a patient questionnaire. This data is combined with a machine learning algorithm to identify patients with asthma and COPD. To test and validate the design, we collected data from 119 healthy and sick participants using our custom mobile application and ran the analysis on a PC computer. For comparison, all subjects were examined by an experienced pulmonologist using a full pulmonary testing laboratory. Employing a two-stage logistic regression model, our algorithms were first able to identify patients with either asthma or COPD from the general population, yielding an ROC curve with an AUC of 0.95. Then, after identifying these patients, our algorithm was able to distinguish between patients with asthma and patients with COPD, yielding an ROC curve with AUC of 0.97. This work represents an important milestone towards creating a self-contained mobile phone-based platform that can be used for screening and diagnosis of pulmonary disease in many parts of the world.

Relationship between dyspnea, peak expiratory flow rate and wheeze in obstructive lung disease.

PubMed

Srisawai, P

1997-05-01

The relationship between dyspnea and airway obstruction is complex, and it is unclear to what extent measures of each correlate in patients with obstructive lung disease (OLD). Thus, the correlation between subjective assessment of dyspnea (dyspnea score using modified Borg scale) and objective assessment of dyspnea (peak expiratory flow rate using Mini Wright Peak Flow Meter and wheeze score using stethoscope) before and after bronchodilator (1 mg of turbutaline sulphate) were studied in 115 patients (62 males, 53 females) with OLD attending the chest clinic of Royal Irrigation Hospital, Nonthaburi, Thailand. The mean age of these patients was 47.4 +/- 16.4 years. Good correlations were found (r = 0.37 to 0.52; p < 0.001) but dyspnea scores were better correlated with wheeze scores than peak expiratory flow rates. The change in dyspnea scores after bronchodilator also correlated with the change in peak expiratory flow rates and the change in wheeze scores (r = 0.22; p < 0.02 and r = 0.28; p < 0.005 respectively). Analyzing a subgroup of 48 dyspneic patients (prebronchodilator dyspnea score of 2 or more) revealed the following response groups: those with either a bronchodilator or dyspnea response alone, both together, or neither. Twenty-three patients (47.92 per cent) responded both subjectively and objectively. One (2.08 per cent) had a bronchodilator response only. Twenty (41.66 per cent) had a dyspnea response only, while four (8.33 per cent) had neither measurable response. The present study suggests that the assessment of dyspnea by using dyspnea score is vital and may be specially helpful in a situation where the objective assessment cannot be performed. In some individuals the subjective assessment of response to bronchodilator may be at least as valuable as objective data.

International perception of lung sounds: a comparison of classification across some European borders.

PubMed

Aviles-Solis, Juan Carlos; Vanbelle, Sophie; Halvorsen, Peder A; Francis, Nick; Cals, Jochen W L; Andreeva, Elena A; Marques, Alda; Piirilä, Päivi; Pasterkamp, Hans; Melbye, Hasse

2017-01-01

Lung auscultation is helpful in the diagnosis of lung and heart diseases; however, the diagnostic value of lung sounds may be questioned due to interobserver variation. This situation may also impair clinical research in this area to generate evidence-based knowledge about the role that chest auscultation has in a modern clinical setting. The recording and visual display of lung sounds is a method that is both repeatable and feasible to use in large samples, and the aim of this study was to evaluate interobserver agreement using this method. With a microphone in a stethoscope tube, we collected digital recordings of lung sounds from six sites on the chest surface in 20 subjects aged 40 years or older with and without lung and heart diseases. A total of 120 recordings and their spectrograms were independently classified by 28 observers from seven different countries. We employed absolute agreement and kappa coefficients to explore interobserver agreement in classifying crackles and wheezes within and between subgroups of four observers. When evaluating agreement on crackles (inspiratory or expiratory) in each subgroup, observers agreed on between 65% and 87% of the cases. Conger's kappa ranged from 0.20 to 0.58 and four out of seven groups reached a kappa of ≥0.49. In the classification of wheezes, we observed a probability of agreement between 69% and 99.6% and kappa values from 0.09 to 0.97. Four out of seven groups reached a kappa ≥0.62. The kappa values we observed in our study ranged widely but, when addressing its limitations, we find the method of recording and presenting lung sounds with spectrograms sufficient for both clinic and research. Standardisation of terminology across countries would improve international communication on lung auscultation findings.

Respiratory Rate During the First 24 Hours of Life in Healthy Term Infants.

PubMed

Tveiten, Lars; Diep, Lien My; Halvorsen, Thomas; Markestad, Trond

2016-04-01

Abnormal respiratory rate (RR) is a key symptom of disease in the newborn. The aim of this study was to establish the reference range for RR during the first 24 hours of life in healthy infants born at term. Infants were included at the hospital postnatal ward when time permitted. During sleep or a defined quiet state, RR was counted at 2, 4, 8, 16, and 24 hours by placing the bell of a stethoscope in front of the nostrils and mouth for 60 seconds. Data on maternal health, pregnancies, and births were obtained from medical records and the Medical Birth Registry of Norway. The study included 953 infants. Median RRs were 46 breaths/minute at 2 hours, thereafter 42 to 44 breaths/minute. The 95th percentile was 65 breaths/minute at 2 hours, thereafter 58 to 60 breaths/minute. The fifth percentile was 30 to 32 breaths/minute. Within these limits, the intraindividual variation was wide. The overall mean RR was 5.2 (95% confidence interval [CI], 4.7 to 5.7, P < .001) breaths/minute higher while awake than during sleep, 3.1 (95% CI, 1.5 to 4.8, P < .001) breaths/minute higher after heavy meconium staining of the amniotic fluid, and 1.6 (95% CI, 0.8 to 2.4, P < .001) breaths/minute higher in boys than girls. RR did not differ for infants born after vaginal versus cesarean deliveries. The RR percentiles established from this study allow for a scientifically based use of RR when assessing newborn infants born at term. Copyright © 2016 by the American Academy of Pediatrics.

Developing a reference of normal lung sounds in healthy Peruvian children.

PubMed

Ellington, Laura E; Emmanouilidou, Dimitra; Elhilali, Mounya; Gilman, Robert H; Tielsch, James M; Chavez, Miguel A; Marin-Concha, Julio; Figueroa, Dante; West, James; Checkley, William

2014-10-01

Lung auscultation has long been a standard of care for the diagnosis of respiratory diseases. Recent advances in electronic auscultation and signal processing have yet to find clinical acceptance; however, computerized lung sound analysis may be ideal for pediatric populations in settings, where skilled healthcare providers are commonly unavailable. We described features of normal lung sounds in young children using a novel signal processing approach to lay a foundation for identifying pathologic respiratory sounds. 186 healthy children with normal pulmonary exams and without respiratory complaints were enrolled at a tertiary care hospital in Lima, Peru. Lung sounds were recorded at eight thoracic sites using a digital stethoscope. 151 (81%) of the recordings were eligible for further analysis. Heavy-crying segments were automatically rejected and features extracted from spectral and temporal signal representations contributed to profiling of lung sounds. Mean age, height, and weight among study participants were 2.2 years (SD 1.4), 84.7 cm (SD 13.2), and 12.0 kg (SD 3.6), respectively; and, 47% were boys. We identified ten distinct spectral and spectro-temporal signal parameters and most demonstrated linear relationships with age, height, and weight, while no differences with genders were noted. Older children had a faster decaying spectrum than younger ones. Features like spectral peak width, lower-frequency Mel-frequency cepstral coefficients, and spectro-temporal modulations also showed variations with recording site. Lung sound extracted features varied significantly with child characteristics and lung site. A comparison with adult studies revealed differences in the extracted features for children. While sound-reduction techniques will improve analysis, we offer a novel, reproducible tool for sound analysis in real-world environments.

Assessment and management of children aged 1-59 months presenting with wheeze, fast breathing, and/or lower chest indrawing; results of a multicentre descriptive study in Pakistan.

PubMed

Hazir, T; Qazi, S; Nisar, Y B; Ansari, S; Maqbool, S; Randhawa, S; Kundi, Z; Asghar, R; Aslam, S

2004-11-01

Using current WHO guidelines, children with wheezing are being over prescribed antibiotics and bronchodilators are underutilised. To improve the WHO case management guidelines, more data is needed about the clinical outcome in children with wheezing/pneumonia overlap. In a multicentre prospective study, children aged 1-59 months with auscultatory/audible wheeze and fast breathing and/or lower chest indrawing were screened. Response to up to three cycles of inhaled salbutamol was recorded. The responders were enrolled and sent home on inhaled bronchodilators, and followed up on days 3 and 5. A total of 1622 children with wheeze were screened from May 2001 to April 2002, of which 1004 (61.8%) had WHO defined non-severe and 618 (38.2%) severe pneumonia. Wheeze was audible in only 595 (36.7%) of children. Of 1004 non-severe pneumonia children, 621 (61.8%) responded to up to three cycles of bronchodilator. Of 618 severe pneumonia children, only 166 (26.8%) responded. Among responders, 93 (14.9%) in the non-severe and 63 (37.9%) children in the severe pneumonia group showed subsequent deterioration on follow ups. No family history of wheeze, temperature >100 degrees F, and lower chest indrawing were identified as predictors of subsequent deterioration. Two third of children with wheeze are not identified by current WHO ARI (acute respiratory infections) guidelines. Antibiotics are over prescribed and bronchodilators under utilised in children with wheeze. Children with wheeze constitute a special ARI group requiring a separate management algorithm. In countries where wheeze is common it would be worthwhile to train health workers in use of the stethoscope to identify wheeze.

Adenosine bronchial provocation with computerized wheeze detection in young infants with prolonged cough: correlation with long-term follow-up.

PubMed

Bentur, Lea; Beck, Raphael; Berkowitz, Drora; Hasanin, Jamal; Berger, Irit; Elias, Nael; Gavriely, Noam

2004-10-01

Chronic cough in babies is often associated with bronchial hyperreactivity (BHR). The objective documentation of BHR in babies is difficult, and acoustic methods have been described (provocative concentration of a substance causing wheeze) for conducting bronchial provocation tests (BPTs). We conducted a study to evaluate automatic computerized wheeze detection (CWD) in determining BHR in young infants with prolonged cough, and its correlation with the subsequent development of wheezing. Infants aged < 24 months with prolonged cough (ie, > 2 months) underwent acoustic BPTs with the response determined by CWD and auscultation by a physician. Telephone interviews with parents were conducted after 1 month and yearly for the next 3 years. A total of 28 infants who were 4 to 24 months old with prolonged cough were included in the study. Twenty of these infants (71.4%) had BHR as determined by a positive acoustic BPT result. In 11 of these 20 tests, the CWD occurred earlier, and in 9 tests it occurred at the same step as auscultation by a physician. Rhonchi or whistles often preceded wheezes. Seventeen of the 20 patients with BHR completed 3 years of follow-up. Of these, 14 had recurrent episodes of wheezing and shortness of breath, and 3 were well. Six of the eight adenosine-negative patients completed 3 years of follow-up and had no symptoms of BHR. Acoustic BPT is a technically feasible test for the detection of BHR in young infants. CWD provides an earlier detection of wheeze than stethoscope auscultation. In our group of infants, a positive acoustic BPT result had high correlation with symptoms compatible with BHR over the next 3 years.

Extensive severe fever with thrombocytopenia syndrome virus contamination in surrounding environment in patient rooms.

PubMed

Ryu, B-H; Kim, J Y; Kim, T; Kim, M-C; Kim, M J; Chong, Y-P; Lee, S-O; Choi, S-H; Kim, Y S; Woo, J H; Kim, S-H

2018-01-31

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease in Korea and China. Although there is previous evidence of person-to-person transmission via direct contact with body fluids, the role of environmental contamination by SFTS virus (SFTSV) in healthcare settings has not been established. We therefore investigated the contamination of the healthcare environment by SFTSV. We investigated the possible contamination of hospital air and surfaces with SFTSV transmission by collecting air and swabbing environmental surface samples in two hospitals treating six SFTS patients between March and September 2017. The samples were tested using real-time RT-PCR for SFTS M and S segments. Of the six SFTS patients, four received mechanical ventilation and three died. Five rooms were occupied by those using mechanical ventilation or total plasma exchange therapy in isolation rooms without negative pressure and one room was occupied by a patient bedridden due to SFTS. SFTSV was detected in 14 (21%) of 67 swab samples. Five of 24 swab samples were obtained from fomites including stethoscopes, and 9 of 43 were obtained from fixed structures including doorknobs and bed guardrails. Some samples from fixed structures such as television monitors and sink tables were obtained in areas remote from the patients. SFTSV RNA was not detected in five air samples from three patients' rooms. Our data suggest that SFTSV contamination was extensive in surrounding environments in SFTS patients' rooms. Therefore, more strict isolation methods and disinfecting procedures should be considered when managing SFTS patients. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

The construction of power in family medicine bedside teaching: a video observation study.

PubMed

Rees, Charlotte E; Ajjawi, Rola; Monrouxe, Lynn V

2013-02-01

Bedside teaching is essential for helping students develop skills, reasoning and professionalism, and involves the learning triad of student, patient and clinical teacher. Although current rhetoric espouses the sharing of power, the medical workplace is imbued with power asymmetries. Power is context-specific and although previous research has explored some elements of the enactment and resistance of power within bedside teaching, this exploration has been conducted within hospital rather than general practice settings. Furthermore, previous research has employed audio-recorded rather than video-recorded observation and has therefore focused on language and para-language at the expense of non-verbal communication and human-material interaction. A qualitative design was adopted employing video- and audio-recorded observations of seven bedside teaching encounters (BTEs), followed by short individual interviews with students, patients and clinical teachers. Thematic and discourse analyses of BTEs were conducted. Power is constructed by students, patients and clinical teachers throughout different BTE activities through the use of linguistic, para-linguistic and non-verbal communication. In terms of language, participants construct power through the use of questions, orders, advice, pronouns and medical/health belief talk. With reference to para-language, participants construct power through the use of interruption and laughter. In terms of non-verbal communication, participants construct power through physical positioning and the possession or control of medical materials such as the stethoscope. Using this paper as a trigger for discussion, we encourage students and clinical teachers to reflect critically on how their verbal and non-verbal communication constructs power in bedside teaching. Students and clinical teachers need to develop their awareness of what power is, how it can be constructed and shared, and what it means for the student-patient-doctor relationship within bedside teaching. © Blackwell Publishing Ltd 2013.

Accuracy of blood pressure measurement and anthropometry among volunteer observers in a large community survey.

PubMed

Adams, Claire; Burke, Valerie; Beilin, Lawrie J

2002-04-01

The Busselton Survey is a population survey that is held about every three years. In 1994-1995 a re-survey was held of all past participants and 8,502 attended. Financial constraints precluded employing staff for data collection for blood pressure and anthropometry, these therefore were collected by unpaid lay volunteers. Quality control by a health professional was critical to the assessment and maintenance of accuracy in these measurements. For blood pressure three readings were taken simultaneously by a quality control person and the volunteer using a dual stethoscope. Duplicate anthropometric measurements were taken by a criterion anthropometrist and the volunteer. Inter and intra-observer technical errors of measurement (TEM) were calculated. Sixty-two volunteers were trained to take BP measurements; of these, 38 collected data, and 63 were trained in anthropometry; of these, 30 were suitable as measurers. Training was conducted on a group and individual basis by the quality assurance person for the study both in the Perth metropolitan area and rural Busselton. The TEM for SBP was 1.6 mm Hg (SD 1.0 mm Hg) and 1.5 mm Hg (SD 0.8) for DBP. For skin-folds intra-observer TEM ranged from 0.6 mm to 1.0 mm. Between-observer TEM ranged from 2.1 mm to 5.4 mm. For limb and waist circumferences, intra-observer TEM ranged from 0.3 cm to 1.6 cm. Between-observer TEM for circumferences ranged from 0.5 cm to 1.9 cm. Unpaid volunteer measurers can, if carefully trained and supervised, provide acceptable blood pressure data and anthropometry in large population surveys.

Pulseless electrical activity: a misdiagnosed entity during asphyxia in newborn infants?

PubMed

Patel, Sparsh; Cheung, Po-Yin; Solevåg, Anne Lee; Barrington, Keith J; Kamlin, C Omar Farouk; Davis, Peter G; Schmölzer, Georg M

2018-06-12

The 2015 neonatal resuscitation guidelines added ECG as a recommended method of assessment of an infant's heart rate (HR) when determining the need for resuscitation at birth. However, a recent case report raised concerns about this technique in the delivery room. To compare accuracy of ECG with auscultation to assess asystole in asphyxiated piglets. Neonatal piglets had the right common carotid artery exposed and enclosed with a real-time ultrasonic flow probe and HR was continuously measured and recorded using ECG. This set-up allowed simultaneous monitoring of HR via ECG and carotid blood flow (CBF). The piglets were exposed to 30 min normocapnic alveolar hypoxia followed by asphyxia until asystole, achieved by disconnecting the ventilator and clamping the endotracheal tube. Asystole was defined as zero carotid blood flow and was compared with ECG traces and auscultation for heart sounds using a neonatal/infant stethoscope. Overall, 54 piglets were studied with a median (IQR) duration of asphyxia of 325 (200-491) s. In 14 (26%) piglets, CBF, ECG and auscultation identified asystole. In 23 (43%) piglets, we observed no CBF and no audible heart sounds, while ECG displayed an HR ranging from 15 to 80/min. Sixteen (30%) piglets remained bradycardic (defined as HR of <100/min) after 10 min of asphyxia, identified by CBF, ECG and auscultation. Clinicians should be aware of the potential inaccuracy of ECG assessment during asphyxia in newborn infants and should rather rely on assessment using a combination of auscultation, palpation, pulse oximetry and ECG. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Telemedicine: the slow revolution.

PubMed

Moncrief, Jack W

2014-01-01

The use of interactive video has been recognized as a means of delivering medical support to isolated areas since the 1950s. The Department of Defense recognized early the capacity of telemedicine to deliver medical care and support to front-line military personnel. In 1989, the Texas Telemedicine Project received grants and support from the then American Telephone and Telegraph Company (now AT&T) and the Meadows Foundation of Dallas, Texas, to establish and evaluate telemedicine delivery in central Texas. That project had 6 connected telemedicine sites: 3 in Austin, Texas, and 3 in Giddings, Texas (a small community 55 miles to the southeast of Austin). The sites in Giddings included a chronic outpatient dialysis facility, an inpatient psychiatric hospital, and the emergency department at Giddings Hospital. Patient contact began in April 1991 and continued through March 1993. During that period, data on the 1500 patient contacts made were recorded. After termination of the Texas Telemedicine Project, AT&T continued to provide the transmission lines, and between 1993 and 1996, another 12,000 patient contacts were made. Approximately 80% were dialysis evaluations and 20% were non-dialysis primary care contacts. The original cost of materials and equipment in the Texas Telemedicine Project exceeded $50,000 per site. Today, a secure Internet connection with full-motion video and wireless data transfer to almost any location in the world is achievable with an iPad. Multiple inexpensive applications with connections for electrocardiogram, otoscope, and stethoscope, among others, make this technology extremely inexpensive and user-friendly. The revolution now is rapidly moving forward, with Medicare reimbursing telemedicine contacts in medically underserved areas. Multiple bills are before Congress to expand Medicare and therefore private insurance payment for this service.

[The Present Implementation Status and Problems of Vital-signs Measurement by Community Pharmacists in Home Medical Care in Osaka].

PubMed

Niki, Kazuyuki; Takemura, Miho; Kitagawa, Kyosuke; Shimizu, Ruka; Takahashi, Yuri; Hatabu, Asuka; Uejima, Etsuko

2018-01-01

　While the community-based integrated care systems are in the process of being structured currently, more and more community pharmacists want to learn physical assessment skills. However, no large-scale survey focusing on present implementation status and problems of physical assessment by community pharmacists has been conducted yet. Osaka has the 2nd highest number of community pharmacies in Japan now, and the population aged ≥65 years will be expected to become the 3rd highest in 2025. Thus, Osaka can become a national leading model case for community pharmacists' activity in future home medical care. Therefore, this study aimed to reveal the present implementation status and problems of physical assessment by community pharmacists in Osaka, especially focusing on vital-signs. The questionnaires were sent to all the 3571 insurance pharmacies belonging to the Osaka Pharmaceutical Association and 871 pharmacies responded. Many pharmacists recognized the necessity for vital-signs measurement by pharmacists in home medical care (81.5% of pharmacies that offered home medical care and 75.4% of pharmacies that did not offer one). However, the proportion of pharmacies that conduct vital-signs measurement in home medical care was 18.7%, therefore, it was suggested that the present problem is "many pharmacists cannot conduct vital-signs measurement, although they think it should be conducted". Moreover, the most common reason for not measuring vital-signs was the lack of instruments, such as stethoscopes and sphygmomanometer (43.2%). This is the latest report with a large-scale sample, thus, it can serve as valuable knowledge in considering what pharmacists do for the future.

Towards an unsupervised device for the diagnosis of childhood pneumonia in low resource settings: automatic segmentation of respiratory sounds.

PubMed

Sola, J; Braun, F; Muntane, E; Verjus, C; Bertschi, M; Hugon, F; Manzano, S; Benissa, M; Gervaix, A

2016-08-01

Pneumonia remains the worldwide leading cause of children mortality under the age of five, with every year 1.4 million deaths. Unfortunately, in low resource settings, very limited diagnostic support aids are provided to point-of-care practitioners. Current UNICEF/WHO case management algorithm relies on the use of a chronometer to manually count breath rates on pediatric patients: there is thus a major need for more sophisticated tools to diagnose pneumonia that increase sensitivity and specificity of breath-rate-based algorithms. These tools should be low cost, and adapted to practitioners with limited training. In this work, a novel concept of unsupervised tool for the diagnosis of childhood pneumonia is presented. The concept relies on the automated analysis of respiratory sounds as recorded by a point-of-care electronic stethoscope. By identifying the presence of auscultation sounds at different chest locations, this diagnostic tool is intended to estimate a pneumonia likelihood score. After presenting the overall architecture of an algorithm to estimate pneumonia scores, the importance of a robust unsupervised method to identify inspiratory and expiratory phases of a respiratory cycle is highlighted. Based on data from an on-going study involving pediatric pneumonia patients, a first algorithm to segment respiratory sounds is suggested. The unsupervised algorithm relies on a Mel-frequency filter bank, a two-step Gaussian Mixture Model (GMM) description of data, and a final Hidden Markov Model (HMM) interpretation of inspiratory-expiratory sequences. Finally, illustrative results on first recruited patients are provided. The presented algorithm opens the doors to a new family of unsupervised respiratory sound analyzers that could improve future versions of case management algorithms for the diagnosis of pneumonia in low-resources settings.

Telemedicine is as effective as in-person visits for patients with asthma.

PubMed

Portnoy, Jay M; Waller, Morgan; De Lurgio, Stephen; Dinakar, Chitra

2016-09-01

Access to asthma specialists is a problem, particularly in rural areas, thus presenting an opportunity for management using telemedicine. To compare asthma outcomes during 6 months in children managed by telemedicine vs in-person visits. Children with asthma residing in 2 remote locations were offered the choice of an in-person visit or a telemedicine session at a local clinic. The telemedicine process involved real-time use of a Remote Presence Solution (RPS) equipped with a digital stethoscope, otoscope, and high-resolution camera. A telefacilitator operated the RPS and performed diagnostic and educational procedures, such as spirometry and asthma education. Children in both groups were assessed initially, after 30 days, and at 6 months. Asthma outcome measures included asthma control using validated tools (Asthma Control Test, Childhood Asthma Control Test, and Test for Respiratory and Asthma Control in Kids) and patient satisfaction (telemedicine group only). Noninferiority analysis of asthma control was performed using the minimally important difference of an adjusted asthma control test that combined the 3 age groups. Of 169 children, 100 were seen in-person and 69 via telemedicine. A total of 34 in-person and 40 telemedicine patients completed all 3 visits. All had a small, although statistically insignificant, improvement in asthma control over time. Telemedicine was noninferior to in-person visits. Most of the telemedicine group subjects were satisfied with their experience. Children with asthma seen by telemedicine or in-person visits can achieve comparable degrees of asthma control. Telemedicine can be a viable alternative to traditional in-person physician-based care for the treatment and management of asthma. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Effect of Back Massage Intervention on Anxiety, Comfort, and Physiologic Responses in Patients with Congestive Heart Failure

PubMed Central

Chen, Wei-Ling; Liu, Gin-Jen; Chiang, Ming-Chu; Fu, Mao-Young; Hsieh, Yuan-Kai

2013-01-01

Abstract Background Patients suffering from congestive heart failure (CHF) frequently feel physical suffering and anxiety. Objectives The researchers investigated whether back massage could reduce anxiety, discomfort, and physical suffering in patients with CHF. The effects of gender and severity-dependent response of back massage on anxiety and discomfort in patients were also analyzed. Design The study used a quasi-experimental design with one group pretest and posttest. Participants Sixty-four participants were recruited in southern Taiwan. Outcome measures The modified State Anxiety Inventory, the discomfort Visual Analogue Scale, electronic blood pressure (BP) gauges, stethoscopes and the pulse oximetry were used in this study. Results The participants' systolic BP (F (3, 189)=18.91, p<0.01), diastolic BP (F (3, 189)=13.40, p<0.01), heart rate (F (3, 189)=26.28, p<0.01), and respiratory rates (F (3, 189)=5.77, p<0.01) were significantly decreased after back massage. Oxygen saturation levels showed significant increases (F (3, 189)=42.82, p<0.01). Male participants revealed a more significant reduction in anxiety than the female participants (F (1, 50)=7.27, p=0.01). Those with more severe heart failure and greater levels of anxiety (F (2, 61)=4.31, p=0.02) and systolic BP (F (2, 61)=3.86, p=0.03) demonstrated significantly greater responses to back massage. Conclusions Back massage significantly reduced anxiety in the study population. Systolic BP decreased to a greater degree in the male participants, particularly in those with severe heart failure and greater levels of anxiety and higher systolic BP. This study was conducted without a control group. Randomized clinical trials are needed to validate the effectiveness of back massage on patients with CHF. PMID:23186129

Effect of back massage intervention on anxiety, comfort, and physiologic responses in patients with congestive heart failure.

PubMed

Chen, Wei-Ling; Liu, Gin-Jen; Yeh, Shu-Hui; Chiang, Ming-Chu; Fu, Mao-Young; Hsieh, Yuan-Kai

2013-05-01

Patients suffering from congestive heart failure (CHF) frequently feel physical suffering and anxiety. The researchers investigated whether back massage could reduce anxiety, discomfort, and physical suffering in patients with CHF. The effects of gender and severity-dependent response of back massage on anxiety and discomfort in patients were also analyzed. The study used a quasi-experimental design with one group pretest and posttest. Sixty-four participants were recruited in southern Taiwan. The modified State Anxiety Inventory, the discomfort Visual Analogue Scale, electronic blood pressure (BP) gauges, stethoscopes and the pulse oximetry were used in this study. The participants' systolic BP (F (3, 189)=18.91, p<0.01), diastolic BP (F (3, 189)=13.40, p<0.01), heart rate (F (3, 189)=26.28, p<0.01), and respiratory rates (F (3, 189)=5.77, p<0.01) were significantly decreased after back massage. Oxygen saturation levels showed significant increases (F (3, 189)=42.82, p<0.01). Male participants revealed a more significant reduction in anxiety than the female participants (F (1, 50)=7.27, p=0.01). Those with more severe heart failure and greater levels of anxiety (F (2, 61)=4.31, p=0.02) and systolic BP (F (2, 61)=3.86, p=0.03) demonstrated significantly greater responses to back massage. Back massage significantly reduced anxiety in the study population. Systolic BP decreased to a greater degree in the male participants, particularly in those with severe heart failure and greater levels of anxiety and higher systolic BP. This study was conducted without a control group. Randomized clinical trials are needed to validate the effectiveness of back massage on patients with CHF.

Respiratory modulation of oscillometric cuff pressure pulses and Korotkoff sounds during clinical blood pressure measurement in healthy adults.

PubMed

Chen, Diliang; Chen, Fei; Murray, Alan; Zheng, Dingchang

2016-05-10

Accurate blood pressure (BP) measurement depends on the reliability of oscillometric cuff pressure pulses (OscP) and Korotkoff sounds (KorS) for automated oscillometric and manual techniques. It has been widely accepted that respiration is one of the main factors affecting BP measurement. However, little is known about how respiration affects the signals from which BP measurement is obtained. The aim was to quantify the modulation effect of respiration on oscillometric pulses and KorS during clinical BP measurement. Systolic and diastolic BPs were measured manually from 40 healthy subjects (from 23 to 65 years old) under normal and regular deep breathing. The following signals were digitally recorded during linear cuff deflation: chest motion from a magnetometer to obtain reference respiration, cuff pressure from an electronic pressure sensor to derive OscP, and KorS from a digital stethoscope. The effects of respiration on both OscP and KorS were determined from changes in their amplitude associated with respiration between systole and diastole. These changes were normalized to the mean signal amplitude of OscP and KorS to derive the respiratory modulation depth. Reference respiration frequency, and the frequencies derived from the amplitude modulation of OscP and KorS were also calculated and compared. Respiratory modulation depth was 14 and 40 % for OscP and KorS respectively under normal breathing condition, with significant increases (both p < 0.05) to 16 and 49 % with deeper breathing. There was no statistically significant difference between the reference respiration frequency and those derived from the oscillometric and Korotkoff signals (both p > 0.05) during deep breathing, and for the oscillometric signal during normal breathing (p > 0.05). Our study confirmed and quantified the respiratory modulation effect on the oscillometric pulses and KorS during clinical BP measurement, with increased modulation depth under regular deeper breathing.

Carotid Artery Ultrasonographic Assessment in Patients from the Fremantle Diabetes Study Phase II with Carotid Bruits Detected by Electronic Auscultation

PubMed Central

Knapp, Arthur; Cetrullo, Violetta; Sillars, Brett A.; Lenzo, Nat; Davis, Wendy A.

2014-01-01

Abstract Background: Electronic auscultation appears superior to acoustic auscultation for identifying hemodynamic abnormalities. The aim of this study was to determine whether carotid bruits detected by electronic stethoscope in patients with diabetes are associated with stenoses and increased carotid intima-medial thickness (CIMT). Subjects and Methods: Fifty Fremantle Diabetes Study patients (mean±SD age, 73.7±10.0 years; 38.0% males) with a bruit found by electronic auscultation and 50 age- and sex-matched patients with normal carotid sounds were studied. The degree of stenosis and CIMT were assessed from duplex ultrasonography. Results: Patients with a bruit were more likely to have stenosis of ≥50% and CIMT of >1.0 mm than those without (odds ratios [95% confidence intervals]=14.0 [1.8–106.5] and 5.3 [1.8–15.3], respectively; both P=0.001). For the six patients with stenosis of ≥70%, five had a bruit, and one (with a known total occlusion) did not (odds ratio=5.0 [0.6–42.8]; P=0.22). The sensitivity and specificity of carotid bruit for stenoses of ≥50% were 88% and 58%, respectively; respective values for stenoses of ≥70% were 83% and 52%. The equivalent negative predictive values were 96% and 98%, and positive predictive values were 30% and 10%, respectively. Conclusions: Electronic recording of carotid sounds for later interpretation is convenient and reliable. Most patients with stenoses had an overlying bruit. Most bruits were false positives, but ultrasonography is justified to document extent of disease; CIMT measurement will identify increased vascular risk in most of these patients. The absence of a bruit was rarely a false-negative finding, suggesting that these patients can usually be reassured that they do not have hemodynamically important stenosis. PMID:24988112

Initial Field Test of a Cloud-Based Cardiac Auscultation System to Determine Murmur Etiology in Rural China.

PubMed

Pyles, Lee; Hemmati, Pouya; Pan, J; Yu, Xiaoju; Liu, Ke; Wang, Jing; Tsakistos, Andreas; Zheleva, Bistra; Shao, Weiguang; Ni, Quan

2017-04-01

A system for collection, distribution, and long distant, asynchronous interpretation of cardiac auscultation has been developed and field-tested in rural China. We initiated a proof-of-concept test as a critical component of design of a system to allow rural physicians with little experience in evaluation of congenital heart disease (CHD) to obtain assistance in diagnosis and management of children with significant heart disease. The project tested the hypothesis that acceptable screening of heart murmurs could be accomplished using a digital stethoscope and internet cloud transmittal to deliver phonocardiograms to an experienced observer. Of the 7993 children who underwent school-based screening in the Menghai District of Yunnan Province, Peoples Republic of China, 149 had a murmur noted by a screener. They had digital heart sounds and phonocardiograms collected with the HeartLink tele auscultation system, and underwent echocardiography by a cardiology resident from the First Affiliated Hospital of Kunming Medical University. The digital phonocardiograms, stored on a cloud server, were later remotely reviewed by a board-certified American pediatric cardiologist. Fourteen of these subjects were found to have CHD confirmed by echocardiogram. Using the HeartLink system, the pediatric cardiologist identified 11 of the 14 subjects with pathological murmurs, and missed three subjects with atrial septal defects, which were incorrectly identified as venous hum or Still's murmur. In addition, ten subjects were recorded as having pathological murmurs, when no CHD was confirmed by echocardiography during the field study. The overall test accuracy was 91% with 78.5% sensitivity and 92.6% specificity. This proof-of-concept study demonstrated the feasibility of differentiating pathologic murmurs due to CHD from normal functional heart murmurs with the HeartLink system. This field study is an initial step to develop a cost-effective CHD screening strategy in low-resource settings with a shortage of trained medical professionals and pediatric heart programs.

Monte Carlo simulation of liquid bridge rupture: Application to lung physiology

NASA Astrophysics Data System (ADS)

Alencar, Adriano M.; Wolfe, Elie; Buldyrev, Sergey V.

2006-08-01

In the course of certain lung diseases, the surface properties and the amount of fluids coating the airways changes and liquid bridges may form in the small airways blocking the flow of air, impairing gas exchange. During inhalation, these liquid bridges may rupture due to mechanical instability and emit a discrete sound event called pulmonary crackle, which can be heard using a simple stethoscope. We hypothesize that this sound is a result of the acoustical release of energy that had been stored in the surface of liquid bridges prior to its rupture. We develop a lattice gas model capable of describing these phenomena. As a step toward modeling this process, we address a simpler but related problem, that of a liquid bridge between two planar surfaces. This problem has been analytically solved and we use this solution as a validation of the lattice gas model of the liquid bridge rupture. Specifically, we determine the surface free energy and critical stability conditions in a system containing a liquid bridge of volume Ω formed between two parallel planes, separated by a distance 2h , with a contact angle Θ using both Monte Carlo simulation of a lattice gas model and variational calculus based on minimization of the surface area with the volume and the contact angle constraints. In order to simulate systems with different contact angles, we vary the parameters between the constitutive elements of the lattice gas. We numerically and analytically determine the phase diagram of the system as a function of the dimensionless parameters hΩ-1/3 and Θ . The regions of this phase diagram correspond to the mechanical stability and thermodynamical stability of the liquid bridge. We also determine the conditions for the symmetrical versus asymmetrical rupture of the bridge. We numerically and analytically compute the release of free energy during rupture. The simulation results are in agreement with the analytical solution. Furthermore, we discuss the results in connection to the rupture of similar bridges that exist in diseased lungs.

Crackling sound generation during the formation of liquid bridges: A lattice gas model

NASA Astrophysics Data System (ADS)

Almeida, Alexandre B.; Buldyrev, Sergey V.; Alencar, Adriano M.

2013-08-01

Due to abnormal mechanical instabilities, liquid bridges may form in the small airways blocking airflow. Liquid bridge ruptures during inhalation are the major cause of the crackling adventitious lung sound, which can be heard using a simple stethoscope. Recently, Vyshedskiy and colleagues (2009) [1] described and characterized a crackle sound originated during expiration. However, the mechanism and origin of the expiratory crackle are still controversial. Thus, in this paper, we propose a mechanism for expiratory crackles. We hypothesize that the expiratory crackle sound is a result of the energy released in the form of acoustic waves during the formation of the liquid bridge. The magnitude of the energy released is proportional to the difference in free energy prior and after the bridge formation. We use a lattice gas model to describe the liquid bridge formation between two parallel planes. Specifically, we determine the surface free energy and the conditions of the liquid bridge formation between two parallel planes separated by a distance 2h by a liquid droplet of volume Ω and contact angle Θ, using both Monte Carlo simulation of a lattice gas model and variational calculus based on minimization of the surface area with the volume and the contact angle constrained. We numerically and analytically determine the phase diagram of the system as a function of the dimensionless parameter hΩ and Θ. We can distinguish two different phases: one droplet and one liquid bridge. We observe a hysteresis curve for the energy changes between these two states, and a finite size effect in the bridge formation. We compute the release of free energy during the formation of the liquid bridge and discuss the results in terms of system size. We also calculate the force exerted from liquid bridge on the planes by studying the dependence of the free energy on the separation between the planes 2h. The simulation results are in agreement with the analytical solution.

The Ottawa telehealth project.

PubMed

Cheung, S T; Davies, R F; Smith, K; Marsh, R; Sherrard, H; Keon, W J

1998-01-01

To examine the telehealth system as a means of improving access to cardiac consultations and specialized health services in remote areas of Ontario. The University of Ottawa Heart Institute has set up a telehealth test program, Healthcare and Education Access for Remote Residents by Telecommunications (HEARRT), in collaboration with industry and the provincial and federal government, as well as several remote clinical test sites. The program makes off-site cardiology consultations possible. History taking and physical examinations are conducted by video and electronic stethoscope. Laboratory results and echocardiograms are transmitted by document camera and VCR. The technology is being tested in both stable outpatient and emergency situations. Various telecommunications bandwidths and encoding systems are being evaluated, including satellite and terrestrial-based asynchronous transfer-mode circuits. Patient satisfaction and cost-effectiveness are also being assessed. Bandwidths from as low as 384 kbps using H.320 encoders to 40 Mbps using digital transport of NTSC video signals have been evaluated. Although lower bandwidths are sufficient for sending echocardiographic and electrocardiogram data, bandwidths with transport speeds of 4 to 6 Mbps appear necessary to capture the nuances of the cardiac physical examination. A preliminary satisfaction survey of 19 patients noted that all felt that they could communicate effectively with the cardiologist by video, and each had confidence in the advice offered. None reported that he or she would rather have traveled to the doctor in person. Initial and projected examination of the costs suggested that telehealth will effectively reduce overall health care spending while decreasing travel expenses for rural patients. Telehealth technology is sufficiently sophisticated to allow off-site cardiology assessments. Preliminary results suggest there is a sound business case for the implementation of telehealth technology to meet the needs of remote residents in northern Ontario. Working closely with government and industry, we will develop a marketing and commercialization plan to support the use of this technology throughout Ontario and expand application to patient education and continuing medical education.

Diurnal, seasonal, and sex patterns of heart rate in grip-restrained African giant rats (Cricetomys gambianus, Waterhouse).

PubMed

Dzenda, Tavershima; Ayo, Joseph O; Sinkalu, Victor O; Yaqub, Lukuman S

2015-10-01

This study was carried out to determine heart rate (HR) values, including diurnal, seasonal, and sex patterns, in the African giant rat (Cricetomys gambianus, Waterhouse). HR was measured using stethoscope in grip-restrained African giant rats of either sex (103 bucks and 98 does), live-trapped from a tropical Savannah, and caged individually in the laboratory during the harmattan (cold-dry), hot-dry, and rainy seasons over a 3-year period. The HR fluctuated between 90 and 210 beats per minute (bpm) throughout the study period. Diurnal changes in HR (mean ± SEM) during the hot-dry and rainy seasons were nonsignificant (P > 0.05), but the morning and afternoon values differed (P < 0.01) during the cold-dry season. The HR varied (P < 0.05) among seasons, with peak, nadir, and moderate values recorded during the cold-dry (165.8 ± 0.51 bpm), hot-dry (153.1 ± 0.74 bpm), and rainy (163.4 ± 0.70 bpm) seasons, respectively. Mean HR of bucks was lower than that of does during the cold-dry (P < 0.0001) and hot-dry (P < 0.01) seasons, but sex difference during the rainy season was insignificant (P > 0.05). Overall, mean HR was lower (P < 0.0001) in bucks (158.8 ± 0.53 bpm) than in does (164.8 ± 0.53 bpm). In conclusion, values of HR in African giant rats are shown for the first time. Season, sex, and daytime influenced the HR, and should be considered during clinical evaluations of the rats. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Cluster of cases of severe acute respiratory syndrome among Toronto healthcare workers after implementation of infection control precautions: a case series.

PubMed

Ofner-Agostini, Marianna; Gravel, Denise; McDonald, L Clifford; Lem, Marcus; Sarwal, Shelley; McGeer, Allison; Green, Karen; Vearncombe, Mary; Roth, Virginia; Paton, Shirley; Loeb, Mark; Simor, Andrew

2006-05-01

To review the severe acute respiratory syndrome (SARS) infection control practices, the types of exposure to patients with SARS, and the activities associated with treatment of such patients among healthcare workers (HCWs) who developed SARS in Toronto, Canada, after SARS-specific infection control precautions had been implemented. A retrospective review of work logs and patient assignments, detailed review of medical records of patients with SARS, and comprehensive telephone-based interviews of HCWs who met the case definition for SARS after implementation of infection control precautions. Seventeen HCWs from 6 hospitals developed disease that met the case definition for SARS after implementation of infection control precautions. These HCWs had a mean age (+/-SD) of 39+/-2.3 years. Two HCWs were not interviewed because of illness. Of the remaining 15, only 9 (60%) reported that they had received formal infection control training. Thirteen HCWs (87%) were unsure of proper order in which personal protective equipment should be donned and doffed. Six HCWs (40%) reused items (eg, stethoscopes, goggles, and cleaning equipment) elsewhere on the ward after initial use in a room in which a patient with SARS was staying. Use of masks, gowns, gloves, and eyewear was inconsistent among HCWs. Eight (54%) reported that they were aware of a breach in infection control precautions. HCWs reported fatigue due to an increased number and length of shifts; participants worked a median of 10 shifts during the 10 days before onset of symptoms. Seven HCWs were involved in the intubation of a patient with SARS. One HCW died, and the remaining 16 recovered. Multiple factors were likely responsible for SARS in these HCWs, including the performance of high-risk patient care procedures, inconsistent use of personal protective equipment, fatigue, and lack of adequate infection control training.

Automated graphic assessment of respiratory activity is superior to pulse oximetry and visual assessment for the detection of early respiratory depression during therapeutic upper endoscopy.

PubMed

Vargo, John J; Zuccaro, Gregory; Dumot, John A; Conwell, Darwin L; Morrow, J Brad; Shay, Steven S

2002-06-01

Recommendations from the American Society of Anesthesiologists suggest that monitoring for apnea using the detection of exhaled carbon dioxide (capnography) is a useful adjunct in the assessment of ventilatory status of patients undergoing sedation and analgesia. There are no data on the utility of capnography in GI endoscopy, nor is the frequency of abnormal ventilatory activity during endoscopy known. The aims of this study were to determine the following: (1) the frequency of abnormal ventilatory activity during therapeutic upper endoscopy, (2) the sensitivity of observation and pulse oximetry in the detection of apnea or disordered respiration, and (3) whether capnography provides an improvement over accepted monitoring techniques. Forty-nine patients undergoing therapeutic upper endoscopy were monitored with standard methods including pulse oximetry, automated blood pressure measurement, and visual assessment. In addition, graphic assessment of respiratory activity with sidestream capnography was performed in all patients. Endoscopy personnel were blinded to capnography data. Episodes of apnea or disordered respiration detected by capnography were documented and compared with the occurrence of hypoxemia, hypercapnea, hypotension, and the recognition of abnormal respiratory activity by endoscopy personnel. Comparison of simultaneous respiratory rate measurements obtained by capnography and by auscultation with a pretracheal stethoscope verified that capnography was an excellent indicator of respiratory rate when compared with the reference standard (auscultation) (r = 0.967, p < 0.001). Fifty-four episodes of apnea or disordered respiration occurred in 28 patients (mean duration 70.8 seconds). Only 50% of apnea or disordered respiration episodes were eventually detected by pulse oximetry. None were detected by visual assessment (p < 0.0010). Apnea/disordered respiration occurs commonly during therapeutic upper endoscopy and frequently precedes the development of hypoxemia. Potentially important abnormalities in respiratory activity are undetected with pulse oximetry and visual assessment.

Computerized Respiratory Sounds: Novel Outcomes for Pulmonary Rehabilitation in COPD.

PubMed

Jácome, Cristina; Marques, Alda

2017-02-01

Computerized respiratory sounds are a simple and noninvasive measure to assess lung function. Nevertheless, their potential to detect changes after pulmonary rehabilitation (PR) is unknown and needs clarification if respiratory acoustics are to be used in clinical practice. Thus, this study investigated the short- and mid-term effects of PR on computerized respiratory sounds in subjects with COPD. Forty-one subjects with COPD completed a 12-week PR program and a 3-month follow-up. Secondary outcome measures included dyspnea, self-reported sputum, FEV 1 , exercise tolerance, self-reported physical activity, health-related quality of life, and peripheral muscle strength. Computerized respiratory sounds, the primary outcomes, were recorded at right/left posterior chest using 2 stethoscopes. Air flow was recorded with a pneumotachograph. Normal respiratory sounds, crackles, and wheezes were analyzed with validated algorithms. There was a significant effect over time in all secondary outcomes, with the exception of FEV 1 and of the impact domain of the St George Respiratory Questionnaire. Inspiratory and expiratory median frequencies of normal respiratory sounds in the 100-300 Hz band were significantly lower immediately (-2.3 Hz [95% CI -4 to -0.7] and -1.9 Hz [95% CI -3.3 to -0.5]) and at 3 months (-2.1 Hz [95% CI -3.6 to -0.7] and -2 Hz [95% CI -3.6 to -0.5]) post-PR. The mean number of expiratory crackles (-0.8, 95% CI -1.3 to -0.3) and inspiratory wheeze occupation rate (median 5.9 vs 0) were significantly lower immediately post-PR. Computerized respiratory sounds were sensitive to short- and mid-term effects of PR in subjects with COPD. These findings are encouraging for the clinical use of respiratory acoustics. Future research is needed to strengthen these findings and explore the potential of computerized respiratory sounds to assess the effectiveness of other clinical interventions in COPD. Copyright © 2017 by Daedalus Enterprises.

Analysis of pulmonary sounds for the diagnosis of interstitial lung diseases secondary to rheumatoid arthritis.

PubMed

Pancaldi, Fabrizio; Sebastiani, Marco; Cassone, Giulia; Luppi, Fabrizio; Cerri, Stefania; Della Casa, Giovanni; Manfredi, Andreina

2018-05-01

The diagnosis of interstitial lung diseases in patients affected by rheumatoid arthritis is fundamental to improving their survival rate. In particular, the average survival time of patients affected by rheumatoid arthritis with pulmonary implications is approximately 3 years. The gold standard for confirming the diagnosis of this disease is computer tomography. However, it is very difficult to raise diagnosis suspicion because the symptoms of the disease are extremely common in elderly people. The detection of the so-called velcro crackle in lung sounds can effectively raise the suspicion of an interstitial disease and speed up diagnosis. However, this task largely relies on the experience of physicians and has not yet been standardized in clinical practice. The diagnosis of interstitial lung diseases based on thorax auscultation still represents an underexplored field in the study of rheumatoid arthritis. In this study, we investigate the problem of the automatic detection of velcro crackle in lung sounds. In practice, the patient is auscultated using a digital stethoscope and the lung sounds are saved to a file. The acquired digital data are then analysed using a suitably developed algorithm. In particular, the proposed solution relies on the empirical observation that the audio bandwidth associated with velcro crackle is larger than that associated with healthy breath sounds. Experimental results from a database of 70 patients affected by rheumatoid arthritis demonstrate that the developed tool can outperform specialized physicians in terms of diagnosing pulmonary disorders. The overall accuracy of the proposed solution is 90.0%, with negative and positive predictive values of 95.0% and 83.3%, respectively, whereas the reliability of physician diagnosis is in the range of 60-70%. The devised algorithm represents an enabling technology for a novel approach to the diagnosis of interstitial lung diseases in patients affected by rheumatoid arthritis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Auscultated forced expiratory time as a clinical and epidemiologic test of airway obstruction.

PubMed

Kern, D G; Patel, S R

1991-09-01

Seeking an inexpensive, readily available, clinical, screening, and field surveillance test of airway obstruction, we determined the validity of current dogma that forced expiratory time (FET) is a good clinical test of airway obstruction yet is of no epidemiologic use given excessive intrasubject variability. Two hundred twenty-nine white male plumbers and pipefitters were evaluated by spirometry, chest roentgenography, and a standardized respiratory questionnaire during a union-sponsored asbestos screening program. Subjects were classified as having large airway obstruction (LAO), small airway obstruction (SAO) alone, or no obstruction, on the basis of standard spirometric prediction equations. Two physicians, blinded to clinical and spirometric data, independently measured FET while auscultating the trachea with a stethoscope. The FET was defined as the time taken for an individual to forcefully exhale through an open mouth from total lung capacity until airflow became inaudible. Five such times were recorded for each subject. The mean of the three times having the narrowest range was deemed the FET for calculating test sensitivity and specificity. Based on previous literature, an FET greater than or equal to 6 s was considered abnormally prolonged. Two hundred five subjects completed both spirometry and FET testing; 67 had LAO, 5 SAO, and 133 no obstruction. A total of 83 percent had three FETs reproducible within a range of less than or equal to 1 s. The sensitivity and specificity of FET for LAO were 92 and 43 percent, respectively, while for SAO alone, 60 and 44 percent, respectively. Overall, FET misclassified 56 percent of nonobstructed subjects. Adjusting the normal-abnormal cutoff points for both FET and SAO minimally improved the performance of FET. Although FET is a simple, inexpensive, sensitive, and fairly reproducible clinical test of LAO, it cannot be recommended as a clinical or an epidemiologic tool because of its extremely low specificity.

Novel aspects in diagnostic approach to respiratory patients: is it the time for a new semiotics?

PubMed

Soldati, Gino; Smargiassi, Andrea; Mariani, Alberto A; Inchingolo, Riccardo

2017-01-01

Medical approach to patients is a fundamental step to get the correct diagnosis. The aim of this paper is to analyze some aspects of the reasoning process inherent in medical diagnosis in our era. Pathologic signs (anamnestic data, symptoms, semiotics, laboratory and strumental findings) represent informative phenomena to be integrated for inferring a diagnosis. Thus, diagnosis begins with "signs" and finishes in a probability of disease. The abductive reasoning process is the generation of a hypothesis to explain one or more observations (signs) in order to decide between alternative explanations searching the best one. This process is iterative during the diagnostic activity while collecting further observations and it could be creative generating new knowledge about what has not been experienced before. In the clinical setting the abductive process is not only theoretical, conversely the physical exploitation of the patient (palpation, percussion, auscultation) is always crucial. Through this manipulative abduction, new and still unexpressed information is discovered and evaluated and physicians are able "to think through doing" to get the correct diagnosis. Abductive inferential path originates with an emotional reaction (discovery of the signs), step by step explanations are formed and it ends with another emotional reaction (diagnosis). Few bedside instruments are allowed to physicians to amplify their ability to search for signs. Stethoscope is an example. Similarities between ultrasound exploration and percussion can be found. Bedside ultrasonography can be considered an external amplifier of signs, a particular kind of percussion and represents a valid example of abductive manipulation. In this searching for signs doctors act like detectives and sometimes the discovering of a strategic, unsuspected sign during abductive manipulation could represent the key point for the correct diagnosis. This condition is called serendipity. Ultrasound is a powerful tool for detecting soft, hidden, unexpected and strategic signs.

Tracheal wheezes during methacholine airway challenge (MAC) in workers exposed to occupational hazards.

PubMed

Bohadana, A B; Massin, N; Teculescu, D; Peslin, R

1994-09-01

Methacholine airway challenge (MAC) is a simple and useful means to assess bronchial hyperreactivity in workers exposed to various occupational hazards. Recently, wheeze detection by tracheal auscultation has been proposed as an indicator of bronchial responsiveness during bronchial provocation test in children. Our aim was to examine the relationship between the appearance of wheezes and the concurrent changes in forced expiratory volume in one second (FEV1) observed during MAC test in adults. Three cumulative doses of a methacholine solution (100 micrograms, 500 micrograms and 1500 micrograms) were inhaled by 45 workers with occupational exposure to flour dust. Spirometry was done using an electronic spirometer. Tracheal sounds were recorded with an electronic stethoscope placed over the anterior cervical triangle, 2 cm above the sternal notch. The amplified sounds were stored on magnetic tape, band-pass filtered (50-2000 Hz), and digitized at a sampling rate of 4096 Hz into a GenRad Vibration Control System. Wheezes were detected by fast Fourier transform (FFT) analysis and their presence compared to a 20% fall in FEV1. A positive MAC test by spirometry was found in 12 subjects whereas wheezes were identified in 14 subjects. Among the wheezing subjects, nine had a positive MAC test (range of fall in FEV1 = 20.6 to 42.3%) and five had a negative one (range of fall in FEV1 = 3.6 to 16.9%). Moreover, no wheezes were found in the remaining three subjects with a positive MAC test (range of fall in FEV1 = 20.7 to 27.4%). Taking a 20% fall in FEV1 as reference, wheezes were 75% sensitive and 84.8% specific to detect airflow obstruction. In conclusion, since it carries a significant although small false-negative rate, the acoustic technique based upon wheeze detection cannot, at the present time, fully replace spirometry during airway challenge testing in subjects with suspected asthma.

How do family physicians measure blood pressure in routine clinical practice? National survey of Canadian family physicians.

PubMed

Kaczorowski, Janusz; Myers, Martin G; Gelfer, Mark; Dawes, Martin; Mang, Eric J; Berg, Angelique; Grande, Claudio Del; Kljujic, Dragan

2017-03-01

To describe the techniques currently used by family physicians in Canada to measure blood pressure (BP) for screening for, diagnosing, and treating hypertension. A Web-based cross-sectional survey distributed by e-mail. Stratified random sample of family physicians in Canada. Family physician members of the College of Family Physicians of Canada with valid e-mail addresses. Physicians' self-reported routine methods for recording BP in their practices to screen for, diagnose, and manage hypertension. A total of 774 valid responses were received, for a response rate of 16.2%. Respondents were similar to nonrespondents except for underrepresentation of male physicians. Of 769 respondents, 417 (54.2%) indicated that they used manual office BP measurement with a mercury or aneroid device and stethoscope as the routine method to screen patients for high BP, while 42.9% (330 of 769) reported using automated office BP (AOBP) measurement. The method most frequently used to make a diagnosis of hypertension was AOBP measurement (31.1%, 240 of 771), followed by home BP measurement (22.4%, 173 of 771) and manual office BP measurement (21.4%, 165 of 771). Ambulatory BP monitoring (ABPM) was used for diagnosis by 14.4% (111 of 771) of respondents. The most frequently reported method for ongoing management was home BP monitoring (68.7%, 528 of 769), followed by manual office BP measurement (63.6%, 489 of 769) and AOBP measurement (59.2%, 455 of 769). More than three-quarters (77.8%, 598 of 769) of respondents indicated that ABPM was readily available for their patients. Canadian family physicians exhibit overall high use of electronic devices for BP measurement, However, more efforts are needed to encourage practitioners to follow current Canadian guidelines, which advocate the use of AOBP measurement for hypertension screening, ABPM and home BP measurement for making a diagnosis, and both AOBP and home BP monitoring for ongoing management. Copyright© the College of Family Physicians of Canada.

How do family physicians measure blood pressure in routine clinical practice?

PubMed Central

Kaczorowski, Janusz; Myers, Martin G.; Gelfer, Mark; Dawes, Martin; Mang, Eric J.; Berg, Angelique; Grande, Claudio Del; Kljujic, Dragan

2017-01-01

Abstract Objective To describe the techniques currently used by family physicians in Canada to measure blood pressure (BP) for screening for, diagnosing, and treating hypertension. Design A Web-based cross-sectional survey distributed by e-mail. Setting Stratified random sample of family physicians in Canada. Participants Family physician members of the College of Family Physicians of Canada with valid e-mail addresses. Main outcome measures Physicians’ self-reported routine methods for recording BP in their practices to screen for, diagnose, and manage hypertension. Results A total of 774 valid responses were received, for a response rate of 16.2%. Respondents were similar to nonrespondents except for underrepresentation of male physicians. Of 769 respondents, 417 (54.2%) indicated that they used manual office BP measurement with a mercury or aneroid device and stethoscope as the routine method to screen patients for high BP, while 42.9% (330 of 769) reported using automated office BP (AOBP) measurement. The method most frequently used to make a diagnosis of hypertension was AOBP measurement (31.1%, 240 of 771), followed by home BP measurement (22.4%, 173 of 771) and manual office BP measurement (21.4%, 165 of 771). Ambulatory BP monitoring (ABPM) was used for diagnosis by 14.4% (111 of 771) of respondents. The most frequently reported method for ongoing management was home BP monitoring (68.7%, 528 of 769), followed by manual office BP measurement (63.6%, 489 of 769) and AOBP measurement (59.2%, 455 of 769). More than three-quarters (77.8%, 598 of 769) of respondents indicated that ABPM was readily available for their patients. Conclusion Canadian family physicians exhibit overall high use of electronic devices for BP measurement, However, more efforts are needed to encourage practitioners to follow current Canadian guidelines, which advocate the use of AOBP measurement for hypertension screening, ABPM and home BP measurement for making a diagnosis, and both AOBP and home BP monitoring for ongoing management. PMID:28292817

Beyond signal functions in global obstetric care: Using a clinical cascade to measure emergency obstetric readiness

PubMed Central

Dettinger, Julia; Calkins, Kimberly; Kibore, Minnie; Gachuno, Onesmus; Walker, Dilys

2018-01-01

Background Globally, the rate of reduction in delivery-associated maternal and perinatal mortality has been slow compared to improvements in post-delivery mortality in children under five. Improving clinical readiness for basic obstetric emergencies is crucial for reducing facility-based maternal deaths. Emergency readiness is commonly assessed using tracers derived from the maternal signal functions model. Objective-method We compare emergency readiness using the signal functions model and a novel clinical cascade. The cascades model readiness as the proportion of facilities with resources to identify the emergency (stage 1), treat it (stage 2) and monitor-modify therapy (stage 3). Data were collected from 44 Kenyan clinics as part of an implementation trial. Findings Although most facilities (77.0%) stock maternal signal function tracer drugs, far fewer have resources to practically identify and treat emergencies. In hypertensive emergencies for example, 38.6% of facilities have resources to identify the emergency (Stage 1 readiness, including sphygmomanometer, stethoscope, urine collection device, protein test). 6.8% have the resources to treat the emergency (Stage 2, consumables (IV Kit, fluids), durable goods (IV pole) and drugs (magnesium sulfate and hydralazine). No facilities could monitor or modify therapy (Stage 3). Across five maternal emergencies, the signal functions overestimate readiness by 54.5%. A consistent, step-wise pattern of readiness loss across signal functions and care stage emerged and was profoundly consistent at 33.0%. Significance Comparing estimates from the maternal signal functions and cascades illustrates four themes. First, signal functions overestimate practical readiness by 55%. Second, the cascade’s intuitive indicators can support cross-sector health system or program planners to more precisely measure and improve emergency care. Third, adding few variables to existing readiness inventories permits step-wise modeling of readiness loss and can inform more precise interventions. Fourth, the novel aggregate readiness loss indicator provides an innovative and intuitive approach for modeling health system emergency readiness. Additional testing in diverse contexts is warranted. PMID:29474397

Nursing home provider perceptions of telemedicine for reducing potentially avoidable hospitalizations

PubMed Central

Driessen, Julia; Bonhomme, Andro; Chang, Woody; Nace, David A.; Kavalieratos, Dio; Perera, Subashan; Handler, Steven M.

2016-01-01

Objective Potentially avoidable hospitalizations (PAHs) of nursing home (NH) residents are common, costly, and can have significant economic consequences. Telemedicine has been shown to reduce emergency department and hospitalization of NH residents, yet adoption has been limited and little is known about provider's perceptions and desired functionality for a telemedicine program. The goal of this study was to survey a nationally representative sample of NH physicians and advanced practice providers to quantify provider perceptions and desired functionality of telemedicine in NHs to reduce PAHs. Design/Setting/Participants/Measurement We surveyed physician and advanced practice providers who attended the 2015 AMDA – The Society for Post-Acute and Long-Term Care Medicine Annual Conference about their perceptions of telemedicine and desired attributes of a telemedicine program for managing acute changes of condition associated with PAHs. Results We received surveys from 435 of the 947 conference attendees for a 45.6% response rate. Providers indicated strong agreement with the potential for telemedicine to improve timeliness of care and fill existing service gaps, while disagreeing most with the ideas that telemedicine would reduce care effectiveness and jeopardize resident privacy. Responses indicated clear preferences for the technical requirements of such a program, such as high-quality audio and video and inclusion of an electronic stethoscope, but without strong opinions about who should be performing the consults. Conclusion Among NH providers, there is a high degree of confidence in the potential for a telemedicine solution to PAHs in NHs, as well as concrete views about features of such a solution. Such consensus could be used to drive an approach to telemedicine for PAHs in NHs that retains the theoretical strengths of telemedicine and reflects the needs of facilities, providers, and patients. Further research is needed to objectively study the impact of successful telemedicine implementations on patient, provider, and economic outcomes. PMID:26969534

Nursing Home Provider Perceptions of Telemedicine for Reducing Potentially Avoidable Hospitalizations.

PubMed

Driessen, Julia; Bonhomme, Andro; Chang, Woody; Nace, David A; Kavalieratos, Dio; Perera, Subashan; Handler, Steven M

2016-06-01

Potentially avoidable hospitalizations (PAHs) of nursing home (NH) residents are common, costly, and can have significant economic consequences. Telemedicine has been shown to reduce emergency department and hospitalization of NH residents, yet adoption has been limited and little is known about provider's perceptions and desired functionality for a telemedicine program. The goal of this study was to survey a nationally representative sample of NH physicians and advanced practice providers to quantify provider perceptions and desired functionality of telemedicine in NHs to reduce PAHs. We surveyed physicians and advanced practice providers who attended the 2015 AMDA-The Society for Post-Acute and Long-Term Care Medicine Annual Conference about their perceptions of telemedicine and desired attributes of a telemedicine program for managing acute changes of condition associated with PAHs. We received surveys from 435 of the 947 conference attendees for a 45.9% response rate. Providers indicated strong agreement with the potential for telemedicine to improve timeliness of care and fill existing service gaps, while disagreeing most with the ideas that telemedicine would reduce care effectiveness and jeopardize resident privacy. Responses indicated clear preferences for the technical requirements of such a program, such as high-quality audio and video and inclusion of an electronic stethoscope, but with varying opinions about who should be performing the consults. Among NH providers, there is a high degree of confidence in the potential for a telemedicine solution to PAHs in NHs, as well as concrete views about features of such a solution. Such consensus could be used to drive an approach to telemedicine for PAHs in NHs that retains the theoretical strengths of telemedicine and reflects the needs of facilities, providers, and patients. Further research is needed to objectively study the impact of successful telemedicine implementations on patient, provider, and economic outcomes. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

The introduction of a new consulting technology into the National Health Service (NHS) for Scotland.

PubMed

Heaney, David; Caldow, Jan; McClusky, Christine; King, Gerry; Webster, Karyn; Mair, Fiona; Ferguson, James

2009-01-01

New technologies can change healthcare delivery. Cisco HealthPresence, an integrated platform that combines video, audio, and call center technology with medical information to create a virtual clinic experience, was piloted on emergency department patients. The aim was to assess primary care consultations. Patients were supported by an assistant. The doctor was remote from the patient and collected details and a recommended management plan. The same doctor re-examined the patient face-to-face. All patients completed a questionnaire about the experience. Key staff and a small sample of patients were interviewed. One hundred and five (N = 105) patients were included; 42% were given advice, 25% were prescribed analgesia, 26% were prescribed antibiotics, and 15% were x-rayed. There were early problems with the digital stethoscope. Doctors reported that the management plan changed in 7% of cases after seeing the patient. At least 90% of patients reported a positive experience. All patients and staff interviewed were positive. Staff found equipment to be valid and reliable; a concern was the inability to perform "hands on" examination. Telemedicine requires a change in the way of consulting and staff must be interested in using the technology to understand the differences. As one of the doctors said, "HealthPresence was a positive experience." Greater numbers would be required to validate key findings. As judged by clinicians, HealthPresence was successful and potentially safe for triage of unscheduled cases. Different types of staffing models need to be considered to ensure optimum use of health professionals. This study has shown that, despite some limitations, most HealthPresence consultations were found to be safe and appropriate. Further study of this consultation technology is required. HealthPresence has the potential to transform access to services for many patients, and to improve the effectiveness of delivery across a number of services.

Outbreak of Carbapenem-Resistant Pseudomonas aeruginosa Producing VIM-8, a Novel Metallo-β-Lactamase, in a Tertiary Care Center in Cali, Colombia

PubMed Central

Crespo, M. P.; Woodford, N.; Sinclair, A.; Kaufmann, M. E.; Turton, J; Glover, J.; Velez, J. D.; Castañeda, C. R.; Recalde, M.; Livermore, D. M.

2004-01-01

The prevalence of imipenem resistance among Pseudomonas aeruginosa isolates at a 195-bed tertiary care medical center in Cali, Colombia, rose from 2% in 1996 to 28% in 1997 and to over 40% in 2003. Many isolates showed high-level multiresistance, and phenotypic characterization suggested the spread of a predominant strain with minor variants. Sixty-six resistant isolates collected between February 1999 and July 2003 from hospitalized patients (n = 54) and environmental samples (n = 12) were subjected to a fuller analysis. Genetic fingerprints were compared by pulsed-field gel electrophoresis (PFGE) of SpeI-digested genomic DNA, and blaIMP and blaVIM genes were sought by PCR. PFGE and serotyping indicated that 52 of the 66 isolates belonged to a single strain, with 82% similarity; the PFGE pattern for this organism was designated pattern A. Two further pairs of isolates represented single strains; the remaining nine isolates were unique, and in the case of one isolate, no satisfactory PFGE profile could be obtained. The pattern A isolates were mostly of serotype O12 and were highly resistant to imipenem (MICs, 32 to >256 μg/ml), with this resistance decreased eightfold or more in the presence of EDTA. They yielded amplicons with blaVIM-specific primers, and sequencing of DNA from a representative isolate revealed blaVIM-8, a novel allele with three polymorphisms compared with the sequence of blaVIM-2. Two of these nucleotide changes were silent, but the third determined a Thr139Ala substitution. Only 4 of 13 resistant isolates (2 clinical isolates and 2 environmental isolates) assigned to other PFGE types carried blaVIM alleles, whereas the others were less multiresistant and mostly had lower levels of imipenem resistance (MICs, ≤32 μg/ml) which was not significantly reduced by EDTA. No blaIMP alleles were detected. During 2003, when the environmental study was undertaken, serotype O12 isolates with blaVIM were recovered from sinks and stethoscopes in the most-affected units, although not from the hands of staff; the problem declined once these reservoirs were disinfected and hygienic precautions were reinforced. PMID:15528701

[Hygiene barriers in the hospital--psychological aspects].

PubMed

Bergler, R

1991-03-01

This study was made necessary due to the great extent of hospital infections (720,000 cases) in the Federal Republic of Germany and the fact that the nosocomial infection is the most common infectious disease. Starting with a theoretical explanatory model of hygiene behaviour in clinics, 25 senior physicians, 38 assistant doctors, 31 members of the nursing staff and 20 members of the cleaning personnel and domestic staff in university clinics (surgery, orthopaedics, anaesthesia, gynaecology, paediatrics) were examined in a two-stage sociopsychological investigation. To be checked was the hypothesis that the quality and intensity of hygiene behaviour in clinics rises with the extent of personal hygiene sensitivity, knowledge about hygiene essentials, hygiene risks, causes of infection and possibilities of prophylaxis, exemplary and supervisory behaviour on the part of principals and staff in the clinic, as well as the absoluteness, succinctness, clinic-specificity and compulsoriness of rules of hygiene. General findings: (1) During training hygiene was a subject which did not arouse much interest; 57% admit big deficiencies in training; 60.4% of all those asked saw a big lack of information concerning basic knowledge of hospital hygiene, use of non-reusable materials, disinfection of endoscopes, laser probes etc., antibiotic therapy and strategy, development of resistant germs and their disinfection, ways and chains of infection, asepsis in the operating theatre, disposal of contaminated material, rules of hygiene in dealing with HIV-patients, sterilization of implants etc. (2) Doctors and nursing staff assume a relatively high incidence of hospital infections in their own clinic and in their wake an increase in psychological strain on the part of the patients, as well as higher costs in the health service. The most common hygiene deficiencies are lack of space and storage rooms, no separation of septic and aseptic patients, deficiencies in toilets and bathrooms, inadequate personal hygiene behaviour of staff, lack of protective clothing or no regular change of clothing, shortcomings in disinfection, incorrect use of syringes, stethoscopes, etc., no sterile dressings for wounds, no systematic hygiene control and no official consequences for wrong behaviour.(ABSTRACT TRUNCATED AT 400 WORDS)

Search is on for most outstanding family planning workers and clinics.

PubMed

1994-01-01

The JSI Research and Training Institute, Inc, sponsored a national wide search in the Philippines commencing March 15, 1994, and ending July 7, 1994, for commendable family planning workers. The winners of the competition were selected from five categories: the best family planning volunteer worker, government family planning service worker, nongovernment family planning service worker, a government family planning clinic or center, and a nongovernment family planning clinic or center. Winners in each category were selected at the provincial or chartered city level, regional level, and national level. Nomination forms were made available in Provincial Health Offices or City Health Offices. Nomination criteria involved a worker who must have worked for at least 18 months for a family planning service agency and a volunteer who must have worked at least a year a family planning service agency in referring cases. Clinics or centers must have been in operation for at least 18 months and preferably accredited by the government. Winner selection criteria was based on the number of clients served, the commitment to family planning, and the quality of their work. Nominations were disqualified if workers were involved with performing abortions, coercing clients to practice family planning, or discriminating against any legally acceptable methods of contraception. Provincial selection of the winner occurred on July 15, 1994, and these winners were entered in the regional competition, which was set for August 1 and September 15, 1994. Regional winners competed in the national competition in November 1994. The award for each provincial winner will be a certificate, an aneroid sphygmomanometer, and a stethoscope. Provincial clinics will receive a certificate and a wall clock. Regional winners will receive a certificate and wrist watches. Regional clinics will receive a certificate and an examining table or karaoke sound system. The five national winners will receive a plaque of appreciation, a three day stay in Manila, and a round trip ticket to award ceremonies. Personnel will receive a complete medical kit, while the center will get a refrigerator. An opportunity to visit a family planning program in an Asian country will be provided to national winners.

Listening panel agreement and characteristics of lung sounds digitally recorded from children aged 1–59 months enrolled in the Pneumonia Etiology Research for Child Health (PERCH) case–control study

PubMed Central

Park, Daniel E; Watson, Nora L; Buck, W Chris; Bunthi, Charatdao; Devendra, Akash; Ebruke, Bernard E; Elhilali, Mounya; Emmanouilidou, Dimitra; Garcia-Prats, Anthony J; Githinji, Leah; Hossain, Lokman; Madhi, Shabir A; Moore, David P; Mulindwa, Justin; Olson, Dan; Awori, Juliet O; Vandepitte, Warunee P; Verwey, Charl; West, James E; Knoll, Maria D; O'Brien, Katherine L; Feikin, Daniel R; Hammit, Laura L

2017-01-01

Introduction Paediatric lung sound recordings can be systematically assessed, but methodological feasibility and validity is unknown, especially from developing countries. We examined the performance of acoustically interpreting recorded paediatric lung sounds and compared sound characteristics between cases and controls. Methods Pneumonia Etiology Research for Child Health staff in six African and Asian sites recorded lung sounds with a digital stethoscope in cases and controls. Cases aged 1–59 months had WHO severe or very severe pneumonia; age-matched community controls did not. A listening panel assigned examination results of normal, crackle, wheeze, crackle and wheeze or uninterpretable, with adjudication of discordant interpretations. Classifications were recategorised into any crackle, any wheeze or abnormal (any crackle or wheeze) and primary listener agreement (first two listeners) was analysed among interpretable examinations using the prevalence-adjusted, bias-adjusted kappa (PABAK). We examined predictors of disagreement with logistic regression and compared case and control lung sounds with descriptive statistics. Results Primary listeners considered 89.5% of 792 case and 92.4% of 301 control recordings interpretable. Among interpretable recordings, listeners agreed on the presence or absence of any abnormality in 74.9% (PABAK 0.50) of cases and 69.8% (PABAK 0.40) of controls, presence/absence of crackles in 70.6% (PABAK 0.41) of cases and 82.4% (PABAK 0.65) of controls and presence/absence of wheeze in 72.6% (PABAK 0.45) of cases and 73.8% (PABAK 0.48) of controls. Controls, tachypnoea, >3 uninterpretable chest positions, crying, upper airway noises and study site predicted listener disagreement. Among all interpretable examinations, 38.0% of cases and 84.9% of controls were normal (p<0.0001); wheezing was the most common sound (49.9%) in cases. Conclusions Listening panel and case–control data suggests our methodology is feasible, likely valid and that small airway inflammation is common in WHO pneumonia. Digital auscultation may be an important future pneumonia diagnostic in developing countries. PMID:28883927

Listening panel agreement and characteristics of lung sounds digitally recorded from children aged 1-59 months enrolled in the Pneumonia Etiology Research for Child Health (PERCH) case-control study.

PubMed

McCollum, Eric D; Park, Daniel E; Watson, Nora L; Buck, W Chris; Bunthi, Charatdao; Devendra, Akash; Ebruke, Bernard E; Elhilali, Mounya; Emmanouilidou, Dimitra; Garcia-Prats, Anthony J; Githinji, Leah; Hossain, Lokman; Madhi, Shabir A; Moore, David P; Mulindwa, Justin; Olson, Dan; Awori, Juliet O; Vandepitte, Warunee P; Verwey, Charl; West, James E; Knoll, Maria D; O'Brien, Katherine L; Feikin, Daniel R; Hammit, Laura L

2017-01-01

Paediatric lung sound recordings can be systematically assessed, but methodological feasibility and validity is unknown, especially from developing countries. We examined the performance of acoustically interpreting recorded paediatric lung sounds and compared sound characteristics between cases and controls. Pneumonia Etiology Research for Child Health staff in six African and Asian sites recorded lung sounds with a digital stethoscope in cases and controls. Cases aged 1-59 months had WHO severe or very severe pneumonia; age-matched community controls did not. A listening panel assigned examination results of normal, crackle, wheeze, crackle and wheeze or uninterpretable, with adjudication of discordant interpretations. Classifications were recategorised into any crackle, any wheeze or abnormal (any crackle or wheeze) and primary listener agreement (first two listeners) was analysed among interpretable examinations using the prevalence-adjusted, bias-adjusted kappa (PABAK). We examined predictors of disagreement with logistic regression and compared case and control lung sounds with descriptive statistics. Primary listeners considered 89.5% of 792 case and 92.4% of 301 control recordings interpretable. Among interpretable recordings, listeners agreed on the presence or absence of any abnormality in 74.9% (PABAK 0.50) of cases and 69.8% (PABAK 0.40) of controls, presence/absence of crackles in 70.6% (PABAK 0.41) of cases and 82.4% (PABAK 0.65) of controls and presence/absence of wheeze in 72.6% (PABAK 0.45) of cases and 73.8% (PABAK 0.48) of controls. Controls, tachypnoea, >3 uninterpretable chest positions, crying, upper airway noises and study site predicted listener disagreement. Among all interpretable examinations, 38.0% of cases and 84.9% of controls were normal (p<0.0001); wheezing was the most common sound (49.9%) in cases. Listening panel and case-control data suggests our methodology is feasible, likely valid and that small airway inflammation is common in WHO pneumonia. Digital auscultation may be an important future pneumonia diagnostic in developing countries.

What Factors Influence Community Oral and Maxillofacial Surgeons' Choice to Use Capnography in the Office-Based Ambulatory Anesthesia Setting?

PubMed

Matin, Mehdi B; Gonzalez, Martin L; Dodson, Thomas B

2015-08-01

The American Association of Oral and Maxillofacial Surgeons Board of Trustees mandated monitoring using capnography during moderate sedation (MS) and deep sedation or general anesthesia (DS/GA) delivered in the office setting effective January 1, 2014. The purpose of this study was to estimate the frequency of capnography use and to identify variables associated with a clinician's choice to use capnography before the mandate. To address the research purpose, the authors designed a prospective cohort study and enrolled 2 samples: 1) American private practicing oral and maxillofacial surgeons (OMSs) and 2) all eligible patients for whom these OMSs delivered MS or DS/GA. The predictor variables were categorized as surgeon or patient demographics, anesthesia risk factors, procedure-related variables, and anesthetic medications. The outcome variable was capnography use during MS or DS/GA. Descriptive, bivariate, and forward stepwise multiple logistic regression statistics were computed to evaluate the association between the predictor variables and capnography use, with statistical significance set at a P value less than or equal to .05. The surgeon sample was composed of 95 OMSs and 13.7% reported using capnography. The patient sample included 3,495 patients with a mean age of 30.6 years (standard deviation, 17.8 yr), 43.5% were men, and 5.6% were monitored using capnography. Based on bivariate analyses, 17 variables were associated with capnography use. Forward stepwise regression modeling identified 9 variables statistically associated with capnography use. These variables were patient's age, Mallampati airway score, alcohol consumption, board certification, sevoflurane use, number of monitoring methods, electrocardiogram use, precordial stethoscope use, and number of personnel in operating suite. Although this study might be of historical interest at this time, the results offer insight into OMSs' practice patterns before the mandatory requirement to use capnography. As more OMSs comply with the capnography mandate, their practice patterns involving variables found to statistically correlate with capnography use might become more similar to those of early adopters of this technology. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Vibration response imaging: protocol for a systematic review.

PubMed

Berry, Marc P; Camporota, Luigi; Ntoumenopoulos, George

2013-09-25

The concept of lung sounds conveying information regarding lung physiology has been used extensively in clinical practice, particularly with physical auscultation using a stethoscope. Advances in computer technology have facilitated the construction of dynamic visual images derived from recorded lung sounds. Arguably, the most significant progress in this field was the development of the commercially available vibration response imaging (VRI) (Deep Breeze Ltd, Or-Akiva, Israel). This device provides a non-invasive, dynamic image of both lungs constructed from sounds detected from the lungs using surface sensors. In the literature, VRI has been utilized in a multitude of clinical and research settings. This systematic review aims to address three study questions relating to whether VRI can be used as an evaluative device, whether the images generated can be characterized, and which tools and measures have been used to assess these images. This systematic review will involve implementing search strategies in five online journal databases in order to extract articles relating to the application of VRI. Appropriate articles will be identified against a set of pre-determined eligibility criteria and assessed for methodological quality using a standardized scale. Included articles will have data extracted by the reviewers using a standardized evidence table. A narrative synthesis based on a standardized framework will be conducted, clustering evidence into three main groups; one for each of the study questions. A meta-analysis will be conducted if two or more research articles meet pre-determined criteria that allow quantitative synthesis to take place. This systematic review aims to provide a complete overview of the scope of VRI in the clinical and research settings, as well as to discuss methods to interpret the data obtained from VRI. The systematic review intends to help clinicians to make informed decisions on the clinical applicability of the device, to allow researchers to identify further potential avenues of investigation, and to provide methods for the evaluation and interpretation of dynamic and static images. The publication and registration of this review with PROSPERO provides transparency and accountability, and facilitates the appraisal of the proposed systematic review against the original design. PROSPERO registration number: CRD42013003751.

Telemedicine Versus Face-to-Face Evaluations by Respiratory Therapists of Mechanically Ventilated Neonates and Children: A Pilot Study.

PubMed

Bell, Rebecca C; Yager, Phoebe H; Clark, Maureen E; Roumiantsev, Serguei; Venancio, Heather L; Chipman, Daniel W; Kacmarek, Robert M; Noviski, Natan N

2016-02-01

Mechanical ventilation is one of the most important therapeutic interventions in neonatal and pediatric ICUs. Telemedicine has been shown to reliably extend pediatric intensivist expertise to facilities where expertise is limited. If reliable, telemedicine may extend the reach of pediatric respiratory therapists (RTs) to facilities where expertise does not exist or free up existing RT resources for important face-to-face activities in facilities where expertise is limited. The aim of this study was to determine how well respiratory assessments for ventilated neonates and children correlated when performed simultaneously by 2 RTs face-to-face and via telemedicine. We conducted a pilot study including 40 assessments by 16 RTs on 11 subjects (5 neonatal ICU; 6 pediatric ICU). Anonymously completed intake forms by 2 different RTs concurrently assessing 14 ventilator-derived and patient-based respiratory variables were used to determine correlations. Forty paired assessments were performed. Median telemedicine assessment time was 8 min. The Pearson correlation coefficient (r) was used to determine agreement between continuous data, and the Cohen kappa statistics were used for binary variables. Pressure control, PEEP, breathing frequency, and FIO2 perfectly correlated (r = 1, all P < .001) as did the presence of a CO2 monitor and need for increased ventilatory support (kappa = 1). The Pearson correlation coefficient for VT, minute ventilation, mean airway pressure, and oxygen saturation ranged from 0.84 to 0.97 (all P < .001). kappa = 0.41 (95% CI 0.02-0.80) for patient-triggered breaths, and kappa = 0.57 (95% CI 0.19-0.94) for breathing frequency higher than set frequency. kappa = -0.25 (95% CI -0.46 to -0.04) for need for suctioning. Telemedicine technology was acceptable to RTs. Telemedicine evaluations highly correlated with face-to-face for 10 of 14 aspects of standard bedside respiratory assessment. Poor correlation was noted for more complex, patient-generated parameters, highlighting the importance of further investigation incorporating a virtual stethoscope. Copyright © 2016 by Daedalus Enterprises.

Detection of Heart Sounds in Children with and without Pulmonary Arterial Hypertension―Daubechies Wavelets Approach

PubMed Central

Elgendi, Mohamed; Kumar, Shine; Guo, Long; Rutledge, Jennifer; Coe, James Y.; Zemp, Roger; Schuurmans, Dale; Adatia, Ian

2015-01-01

Background Automatic detection of the 1st (S1) and 2nd (S2) heart sounds is difficult, and existing algorithms are imprecise. We sought to develop a wavelet-based algorithm for the detection of S1 and S2 in children with and without pulmonary arterial hypertension (PAH). Method Heart sounds were recorded at the second left intercostal space and the cardiac apex with a digital stethoscope simultaneously with pulmonary arterial pressure (PAP). We developed a Daubechies wavelet algorithm for the automatic detection of S1 and S2 using the wavelet coefficient ‘D 6’ based on power spectral analysis. We compared our algorithm with four other Daubechies wavelet-based algorithms published by Liang, Kumar, Wang, and Zhong. We annotated S1 and S2 from an audiovisual examination of the phonocardiographic tracing by two trained cardiologists and the observation that in all subjects systole was shorter than diastole. Results We studied 22 subjects (9 males and 13 females, median age 6 years, range 0.25–19). Eleven subjects had a mean PAP < 25 mmHg. Eleven subjects had PAH with a mean PAP ≥ 25 mmHg. All subjects had a pulmonary artery wedge pressure ≤ 15 mmHg. The sensitivity (SE) and positive predictivity (+P) of our algorithm were 70% and 68%, respectively. In comparison, the SE and +P of Liang were 59% and 42%, Kumar 19% and 12%, Wang 50% and 45%, and Zhong 43% and 53%, respectively. Our algorithm demonstrated robustness and outperformed the other methods up to a signal-to-noise ratio (SNR) of 10 dB. For all algorithms, detection errors arose from low-amplitude peaks, fast heart rates, low signal-to-noise ratio, and fixed thresholds. Conclusion Our algorithm for the detection of S1 and S2 improves the performance of existing Daubechies-based algorithms and justifies the use of the wavelet coefficient ‘D 6’ through power spectral analysis. Also, the robustness despite ambient noise may improve real world clinical performance. PMID:26629704

Assessment of primary health care facilities' service readiness in Nigeria.

PubMed

Oyekale, Abayomi Samuel

2017-03-01

Effective delivery of healthcare services requires availability of adequate infrastructure, diagnostic medical equipment, drugs and well-trained medical personnel. In Nigeria, poor funding and mismanagement often characterize healthcare service delivery thereby affecting coverage and quality of healthcare services. Therefore, the state of service delivery in Nigeria's health sector has come under some persistent criticisms. This paper analyzed service readiness of Primary Health Care (PHC) facilities in Nigeria with focus on availability of some essential drugs and medical equipment. Service Delivery Indicator (SDI) data for PHC in Nigeria were used. The data were collected from 2480 healthcare facilities from 12 states in the Nigeria's 6 geopolitical zones between 2013 and 2014. Data were analyzed with descriptive statistics, Principal Component Analysis (PCA) and Ordinary Least Square regression. Medical disposables such as hand gloves and male condoms were reported to be available in 77.18 and 44.03% of all the healthcare facilities respectively, while immunization services were provided by 86.57%. Functional stethoscopes were reported by 77.22% of the healthcare facilities, while only 68.10% had sphygmomanometers. In the combined healthcare facilities, availability of some basic drugs such as Azithromycin, Nifedipine, Dexamethasone and Misoprostol was low with 10.48, 25.20, 21.94 and 17.06%, respectively, while paracetamol and folic acid both had high availability with 74.31%. Regression results showed that indices of drug and medical equipment availability increased significantly (p < 0.05) among states in southern Nigeria and with presence of some power sources (electricity, generators, batteries and solar), but decreased among dispensaries/health posts. Travel time to headquarters and rural facilities significantly reduced indices of equipment availability (p < 0.05). It was concluded that for Nigeria to ensure better equity in access to healthcare facilities, which would facilitate achievement of some health-related sustainable development goals (SDGs), quality of services at its healthcare facilities should be improved. Given some differences between availability of basic medical equipment and their functionality, and lack of some basic drugs, proper inventory of medical services should be taken with effort put in place to increase funding and ensure proper management of healthcare resources.

Task shifting to non-physician clinicians for integrated management of hypertension and diabetes in rural Cameroon: a programme assessment at two years

PubMed Central

2010-01-01

Background The burden of non-communicable chronic diseases, such as hypertension and diabetes, increases in sub-Saharan Africa. However, the majority of the rural population does still not have access to adequate care. The objective of this study is to examine the effectiveness of integrating care for hypertension and type 2 diabetes by task shifting to non-physician clinician (NPC) facilities in eight rural health districts in Cameroon. Methods Of the 75 NPC facilities in the area, 69 (87%) received basic equipment and training in hypertension and diabetes care. Effectiveness was assessed after two years on status of equipment, knowledge among trained NPCs, number of newly detected patients, retention of patients under care, treatment cost to patients and changes in blood pressure (BP) and fasting plasma glucose (FPG) among treated patients. Results Two years into the programme, of 54 facilities (78%) available for re-assessment, all possessed a functional sphygmomanometer and stethoscope (65% at baseline); 96% stocked antihypertensive drugs (27% at baseline); 70% possessed a functional glucose meter and 72% stocked oral anti-diabetics (15% and 12% at baseline). NPCs' performance on multiple-choice questions of the knowledge-test was significantly improved. During a period of two years, trained NPCs initiated treatment for 796 patients with hypertension and/or diabetes. The retention of treated patients at one year was 18.1%. Hypertensive and diabetic patients paid a median monthly amount of 1.4 and 0.7 Euro respectively for their medication. Among hypertensive patients with ≥ 2 documented visits (n = 493), systolic BP decreased by 22.8 mmHg (95% CI: -20.6 to -24.9; p < 0.0001) and diastolic BP by 12.4 mmHg (-10.9 to -13.9; p < 0.0001). Among diabetic patients (n = 79) FPG decreased by 3.4 mmol/l (-2.3 to -4.5; p < 0.001). Conclusions The integration of hypertension and diabetes into primary health care of NPC facilities in rural Cameroon was feasible in terms of equipment and training, accessible in terms of treatment cost and showed promising BP- and FPG-trends. However, low case-detection rates per NPC and a very high attrition among patients enrolled into care, limited the effectiveness of the programme. PMID:21144064

Emergency Care Capabilities in North East Haiti: A Cross-sectional Observational Study.

PubMed

De Wulf, Annelies; Aluisio, Adam R; Muhlfelder, Dana; Bloem, Christina

2015-12-01

The North East Department is a resource-limited region of Haiti. Health care is provided by hospitals and community clinics, with no formal Emergency Medical System and undefined emergency services. As a paucity of information exists on available emergency services in the North East Department of Haiti, the objective of this study was to assess systematically the existing emergency care resources in the region. This cross-sectional observational study was carried out at all Ministry of Public Health and Population (MSPP)-affiliated hospitals in the North East Department and all clinics within the Fort Liberté district. A modified version of the World Health Organization (WHO) Tool for Situational Analysis to Assess Emergency and Essential Surgical Care and Generic Essential Emergency Equipment Lists were completed for each facility. Three MSPP hospitals and five clinics were assessed. Among hospitals, all had a designated emergency ward with 24 hour staffing by a medical doctor. All hospitals had electricity with backup generators and access to running water; however, none had potable water. All hospitals had x-ray and ultrasound capabilities. No computed tomography scanners existed in the region. Invasive airway equipment and associated medications were not present consistently in the hospitals' emergency care areas, but they were available in the operating rooms. Pulse oximetry was unavailable uniformly. One hospital had intermittently functioning defibrillation equipment, and two hospitals had epinephrine. Basic supplies for managing obstetrical and traumatic emergencies were available at all hospitals. Surgical services were accessible at two hospitals. No critical care services were available in the region. Clinics varied widely in terms of equipment availability. They uniformly had limited emergency medical equipment. The clinics also had inconsistent access to basic assessment tools (sphygmomanometers 20% and stethoscopes 60%). A protocol for transferring patients requiring a higher level of care was present in most (80%) clinics and one of the hospitals. However, no facility had a written protocol for transferring patients to other facilities. One hospital reported intermittent access to an ambulance for transfers. Deficits in the supply of emergency equipment and limited protocols for inter-facility transfers exist in North East Department of Haiti. These essential areas represent appropriate targets for interventions aimed at improving access to emergency care within the North East region of Haiti.

Using a nasogastric tube.

PubMed

Candy, C

1986-09-01

This discussion of the use of a nasogastric tube covers the equipment needed, the method, rehydration and feeding, prolonged nasogastric feeding, and stopping nasogastric feeding. A nasogastric tube is useful when children are unable to drink safely and in sufficient amounts for any of the following reasons: severe dehydration; if intravenous (IV) therapy is unavailable; low birth weight infants; or the child is drowsy or vomiting. Severely malnourished children may be fed initially in this way if they are too weak or anorexic to eat or drink normally. The following equipment is needed: nasogastric tube; lubricating fluid; a syringe; blue litmus paper, if available; adhesive tape; stethoscope if available; and fluid to be given. Explain to the child's parents and the child, if old enough to understand, what will be done; lie infants flat; measure the approximate length from the child's nostril to the ear lobe and then to the top of the abdomen with the tube and mark the position; clean the nostrils to remove the mucus, and lubricate the tip of the tube and gently insert into the nostril; give the child a drink of water if he or she is conscious; continue to pass the tube down until the position marked reaches the nostril; use the syringe to suck up some fluid and test with blue litmus paper to check that the tube is in the stomach; and inject 5-10 ml of fluid (saline or oral rehydration solution, not milk formula) by syringe if satisfied the tube is in the correct position. Where possible, give a continuous drip of fluid. If this is not possible, give frequent small amounts using the syringe as a funnel. If feeding continues for more than 24 hours, clean the nostrils daily with warm water and change the tube to the other nostril every few days. Also keep the mouth very clean with a dilute solution of 8% sodium bicarbonate, if available, or citrus fruit juice. To remove the tube, remove the adhesive tape, take the tube out gently and smoothly, and offer the child a drink and gently cleanse the nostrils. After prolonged nasogastric feeding, a child may experience feeding problems or loss of appetite. Patient and encouragement are needed to establish feeding by mouth again.

Usefulness of bowel sound auscultation: a prospective evaluation.

PubMed

Felder, Seth; Margel, David; Murrell, Zuri; Fleshner, Phillip

2014-01-01

Although the auscultation of bowel sounds is considered an essential component of an adequate physical examination, its clinical value remains largely unstudied and subjective. The aim of this study was to determine whether an accurate diagnosis of normal controls, mechanical small bowel obstruction (SBO), or postoperative ileus (POI) is possible based on bowel sound characteristics. Prospectively collected recordings of bowel sounds from patients with normal gastrointestinal motility, SBO diagnosed by computed tomography and confirmed at surgery, and POI diagnosed by clinical symptoms and a computed tomography without a transition point. Study clinicians were instructed to categorize the patient recording as normal, obstructed, ileus, or not sure. Using an electronic stethoscope, bowel sounds of healthy volunteers (n = 177), patients with SBO (n = 19), and patients with POI (n = 15) were recorded. A total of 10 recordings randomly selected from each category were replayed through speakers, with 15 of the recordings duplicated to surgical and internal medicine clinicians (n = 41) blinded to the clinical scenario. The sensitivity, positive predictive value, and intra-rater variability were determined based on the clinician's ability to properly categorize the bowel sound recording when blinded to additional clinical information. Secondary outcomes were the clinician's perceived level of expertise in interpreting bowel sounds. The overall sensitivity for normal, SBO, and POI recordings was 32%, 22%, and 22%, respectively. The positive predictive value of normal, SBO, and POI recordings was 23%, 28%, and 44%, respectively. Intra-rater reliability of duplicated recordings was 59%, 52%, and 53% for normal, SBO, and POI, respectively. No statistically significant differences were found between the surgical and internal medicine clinicians for sensitivity, positive predictive value, or intra-rater variability. Overall, 44% of clinicians reported that they rarely listened to bowel sounds, whereas 17% reported that they always listened. Auscultation of bowel sounds is not a useful clinical practice when differentiating patients with normal versus pathologic bowel sounds. The listener frequently arrives at an incorrect diagnosis. If routine abdominal auscultation is to be continued, our findings emphasize the need for improvements in training and education as well as advancements in the understanding of the objective acoustical properties of bowel sounds. Copyright © 2014 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

Left-Right Asymmetry in Spectral Characteristics of Lung Sounds Detected Using a Dual-Channel Auscultation System in Healthy Young Adults.

PubMed

Tsai, Jang-Zern; Chang, Ming-Lang; Yang, Jiun-Yue; Kuo, Dar; Lin, Ching-Hsiung; Kuo, Cheng-Deng

2017-06-07

Though lung sounds auscultation is important for the diagnosis and monitoring of lung diseases, the spectral characteristics of lung sounds have not been fully understood. This study compared the spectral characteristics of lung sounds between the right and left lungs and between healthy male and female subjects using a dual-channel auscultation system. Forty-two subjects aged 18-22 years without smoking habits and any known pulmonary diseases participated in this study. The lung sounds were recorded from seven pairs of auscultation sites on the chest wall simultaneously. We found that in four out of seven auscultation pairs, the lung sounds from the left lung had a higher total power (P T ) than those from the right lung. The P T of male subjects was higher than that of female ones in most auscultation pairs. The ratio of inspiration power to expiration power (R I/E ) of lung sounds from the right lung was greater than that from the left lung at auscultation pairs on the anterior chest wall, while this phenomenon was reversed at auscultation pairs on the posterior chest wall in combined subjects, and similarly in both male and female subjects. Though the frequency corresponding to maximum power density of lung sounds (F MPD ) from the left and right lungs was not significantly different, the frequency that equally divided the power spectrum of lung sounds (F 50 ) from the left lung was significantly smaller than that from the right lung at auscultation site on the anterior and lateral chest walls, while it was significantly larger than that of from the right lung at auscultation site on the posterior chest walls. In conclusion, significant differences in the P T , F MPD , F 50 , and R I/E between the left and right lungs at some auscultation pairs were observed by using a dual-channel auscultation system in this study. Structural differences between the left and the right lungs, between the female and male subjects, and between anterior and posterior lungs might account for the observed differences in the spectral characteristics of lung sounds. The dual-channel auscultation system might be useful for future development of digital stethoscopes and power spectral analysis of lung sounds in patients with various kinds of cardiopulmonary diseases.

Anesthetic Implications of Ebola Patient Management: A Review of the Literature and Policies.

PubMed

Missair, Andres; Marino, Michael J; Vu, Catherine N; Gutierrez, Juan; Missair, Alfredo; Osman, Brian; Gebhard, Ralf E

2015-09-01

As of mid-October 2014, the ongoing Ebola epidemic in Western Africa has affected approximately 10,000 patients, approached a 50% mortality rate, and crossed political and geographic borders without precedent. The disease has spread throughout Liberia, Guinea, and Sierra Leone. Isolated cases have arrived in urban centers in Europe and North America. The exponential growth, currently unabated, highlights the urgent need for effective and immediate management protocols for the various health care subspecialties that may care for Ebola virus disease patients. We conducted a comprehensive review of the literature to identify key areas of anesthetic care affected by this disease. The serious potential for "high-risk exposure" and "direct contact" (as defined by the Centers for Disease Control and Prevention) of anesthesiologists caring for Ebola patients prompted this urgent investigation. A search was conducted using MEDLINE/PubMed, MeSH, Cochrane Review, and Google Scholar. Key words included "anesthesia" and/or "ebola" combined with "surgery," "intubation," "laryngoscopy," "bronchoscopy," "stethoscope," "ventilation," "ventilator," "phlebotomy," "venous cannulation," "operating room," "personal protection," "equipment," "aerosol," "respiratory failure," or "needle stick." No language or date limits were applied. We also included secondary-source data from government organizations and scientific societies such as the Centers for Disease Control and Prevention, World Health Organization, American Society of Anesthesiologists, and American College of Surgeons. Articles were reviewed for primary-source data related to inpatient management of Ebola cases as well as evidence-based management guidelines and protocols for the care of Ebola patients in the operative room, infection control, and health care worker personal protection. Two hundred thirty-six articles were identified using the aforementioned terminology in the scientific database search engines. Twenty articles met search criteria for information related to inpatient Ebola virus disease management or animal virology studies as primary or secondary sources. In addition, 9 articles met search criteria as tertiary sources, representing published guidelines. The recommendations developed in this article are based on these 29 source documents. Anesthesia-specific literature regarding the care of Ebola patients is very limited. Secondary-source guidelines and policies represent the majority of available information. Data from controlled animal experiments and tuberculosis patient research provide some evidence for the existing recommendations and identify future guideline considerations.

Left–Right Asymmetry in Spectral Characteristics of Lung Sounds Detected Using a Dual-Channel Auscultation System in Healthy Young Adults

PubMed Central

Tsai, Jang-Zern; Chang, Ming-Lang; Yang, Jiun-Yue; Kuo, Dar; Lin, Ching-Hsiung; Kuo, Cheng-Deng

2017-01-01

Though lung sounds auscultation is important for the diagnosis and monitoring of lung diseases, the spectral characteristics of lung sounds have not been fully understood. This study compared the spectral characteristics of lung sounds between the right and left lungs and between healthy male and female subjects using a dual-channel auscultation system. Forty-two subjects aged 18–22 years without smoking habits and any known pulmonary diseases participated in this study. The lung sounds were recorded from seven pairs of auscultation sites on the chest wall simultaneously. We found that in four out of seven auscultation pairs, the lung sounds from the left lung had a higher total power (PT) than those from the right lung. The PT of male subjects was higher than that of female ones in most auscultation pairs. The ratio of inspiration power to expiration power (RI/E) of lung sounds from the right lung was greater than that from the left lung at auscultation pairs on the anterior chest wall, while this phenomenon was reversed at auscultation pairs on the posterior chest wall in combined subjects, and similarly in both male and female subjects. Though the frequency corresponding to maximum power density of lung sounds (FMPD) from the left and right lungs was not significantly different, the frequency that equally divided the power spectrum of lung sounds (F50) from the left lung was significantly smaller than that from the right lung at auscultation site on the anterior and lateral chest walls, while it was significantly larger than that of from the right lung at auscultation site on the posterior chest walls. In conclusion, significant differences in the PT, FMPD, F50, and RI/E between the left and right lungs at some auscultation pairs were observed by using a dual-channel auscultation system in this study. Structural differences between the left and the right lungs, between the female and male subjects, and between anterior and posterior lungs might account for the observed differences in the spectral characteristics of lung sounds. The dual-channel auscultation system might be useful for future development of digital stethoscopes and power spectral analysis of lung sounds in patients with various kinds of cardiopulmonary diseases. PMID:28590447

Teaching appropriate interactions with pharmaceutical company representatives: the impact of an innovative workshop on student attitudes.

PubMed

Wofford, James L; Ohl, Christopher A

2005-02-08

Pharmaceutical company representatives (PCRs) influence the prescribing habits and professional behaviour of physicians. However, the skills for interacting with PCRs are not taught in the traditional medical school curriculum. We examined whether an innovative, mandatory workshop for third year medical students had immediate effects on knowledge and attitudes regarding interactions with PCRs. Surveys issued before and after the workshop intervention solicited opinions (five point Likert scales) from third year students (n = 75) about the degree of bias in PCR information, the influence of PCRs on prescribing habits, the acceptability of specific gifts, and the educational value of PCR information for both practicing physicians and students. Two faculty members and one PCR led the workshop, which highlighted typical physician-PCR interactions, the use of samples and gifts, the validity and legal boundaries of PCR information, and associated ethical issues. Role plays with the PCR demonstrated appropriate and inappropriate strategies for interacting with PCRs. The majority of third year students (56%, 42/75) had experienced more than three personal conversations with a PCR about a drug product since starting medical school. Five percent (4/75) claimed no previous personal experience with PCRs. Most students (57.3%, 43/75) were not aware of available guidelines regarding PCR interactions. Twenty-eight percent of students (21/75) thought that none of the named activities/gifts (lunch access, free stethoscope, textbooks, educational CD-ROMS, sporting events) should be restricted, while 24.0% (8/75) thought that students should be restricted only from sporting events. The perceived educational value of PCR information to both practicing physicians and students increased after the workshop intervention from 17.7% to 43.2% (chi square, p = .0001), and 22.1% to 40.5% (p = .0007), respectively. Student perceptions of the degree of bias of PCR information decreased from 84.1% to 72.9% (p = .065), but the perceived degree of influence on prescribing increased (44.2% to 62.1% (p = .02)). Students have exposure to PCRs early in their medical training. A single workshop intervention may influence student attitudes toward interactions with PCRs. Students were more likely to acknowledge the educational value of PCR interactions and their impact on prescribing after the workshop intervention.

Functionality and acceptability of a wireless fetal heart rate monitoring device in term pregnant women in rural Southwestern Uganda.

PubMed

Mugyenyi, Godfrey R; Atukunda, Esther C; Ngonzi, Joseph; Boatin, Adeline; Wylie, Blair J; Haberer, Jessica E

2017-06-08

Over 3 million stillbirths occur annually in sub Saharan Africa; most occur intrapartum and are largely preventable. The standard of care for fetal heart rate (FHR) assessment in most sub-Saharan African settings is a Pinard Stethoscope, limiting observation to one person, at one point in time. We aimed to test the functionality and acceptability of a wireless FHR monitor that could allow for expanded monitoring capacity in rural Southwestern Uganda. In a mixed method prospective study, we enrolled 1) non-laboring healthy term pregnant women to wear the device for 30 min and 2) non-study clinicians to observe its use. The battery-powered prototype uses Doppler technology to measure fetal cardiotocographs (CTG), which are displayed via an android device and wirelessly transmit to cloud storage where they are accessible via a password protected website. Prototype functionality was assessed by the ability to obtain and transmit a 30-min CTG. Three obstetricians independently rated CTGs for readability and agreement between raters was calculated. All participants completed interviews on acceptability. Fifty pregnant women and 7 clinicians were enrolled. 46 (92.0%) CTGs were successfully recorded and stored. Mean scores for readability were 4.71, 4.71 and 4.83 (out of 5) with high agreement (intra class correlation 0.84; 95% CI 0.74 to 0.91). All pregnant women reported liking or really liking the device, as well as high levels of comfort, flexibility and usefulness of the prototype; all would recommend it to others. Clinicians described the prototype as portable, flexible, easy-to-use and a time saver. Adequate education for clinicians and women also seemed to improve correct usage and minimise concerns on safety of the device. This prototype wireless FHR monitor functioned well in a low-resource setting and was found to be acceptable and useful to both pregnant women and clinicians. The device also seemed to have potential to improve the experience of the users compared with standard of care and expand monitoring capacity in settings where bulky, wired or traditional equipment are unreliable. Further research needs to investigate the potential impact and cost of such innovations to improve perinatal outcomes.

Capacity of Health Facilities to Manage Hypertension in Mukono and Buikwe Districts in Uganda: Challenges and Recommendations

PubMed Central

Musinguzi, Geofrey; Bastiaens, Hilde; Wanyenze, Rhoda K.; Mukose, Aggrey; Van geertruyden, Jean-Pierre; Nuwaha, Fred

2015-01-01

Background The burden of chronic diseases is increasing in both low- and middle-income countries. However, healthcare systems in low-income countries are inadequately equipped to deal with the growing disease burden, which requires chronic care for patients. The aim of this study was to assess the capacity of health facilities to manage hypertension in two districts in Uganda. Methods In a cross-sectional study conducted between June and October 2012, we surveyed 126 health facilities (6 hospitals, 4 Health Center IV (HCIV), 23 Health Center III (HCIII), 41 Health Center II (HCII) and 52 private clinics/dispensaries) in Mukono and Buikwe districts in Uganda. We assessed records, conducted structured interviews with heads of facilities, and administered questionnaires to 271 health workers. The study assessed service provision for hypertension, availability of supplies such as medicines, guidelines and equipment, in-service training for hypertension, knowledge of hypertension management, challenges and recommendations. Results Of the 126 health facilities, 92.9% reported managing (diagnosing/treating) patients with hypertension, and most (80.2%) were run by non-medical doctors or non-physician health workers (NPHW). Less than half (46%) of the facilities had guidelines for managing hypertension. A 10th of the facilities lacked functioning blood pressure devices and 28% did not have stethoscopes. No facilities ever calibrated their BP devices except one. About a half of the facilities had anti-hypertensive medicines in stock; mainly thiazide diuretics (46%), beta blockers (56%) and calcium channel blockers (48.4%). Alpha blockers, mixed alpha & beta blockers and angiotensin II receptor antagonists were only stocked by private clinics/dispensaries. Most HCIIs lacked anti-hypertensive medicines, including the first line thiazide diuretics. Significant knowledge gaps in classification of patients as hypertensive were noted among respondents. All health workers (except 5, 1.9%) indicated that they needed additional training in hypertension management. Several provider and patient related challenges were also observed in this study. Conclusions Health facilities in this setting are inadequately equipped to provide services for management of hypertension. Diagnostic equipment, anti-hypertensive drugs and personnel present great challenges. To address the increasing burden of hypertension and other chronic diseases, measures are needed to substantially strengthen the healthcare facilities, including training of personnel in management of hypertension and other chronic diseases, and improving diagnostic and treatment supplies. PMID:26560131

Capacity of Health Facilities to Manage Hypertension in Mukono and Buikwe Districts in Uganda: Challenges and Recommendations.

PubMed

Musinguzi, Geofrey; Bastiaens, Hilde; Wanyenze, Rhoda K; Mukose, Aggrey; Van Geertruyden, Jean-Pierre; Nuwaha, Fred

2015-01-01

The burden of chronic diseases is increasing in both low- and middle-income countries. However, healthcare systems in low-income countries are inadequately equipped to deal with the growing disease burden, which requires chronic care for patients. The aim of this study was to assess the capacity of health facilities to manage hypertension in two districts in Uganda. In a cross-sectional study conducted between June and October 2012, we surveyed 126 health facilities (6 hospitals, 4 Health Center IV (HCIV), 23 Health Center III (HCIII), 41 Health Center II (HCII) and 52 private clinics/dispensaries) in Mukono and Buikwe districts in Uganda. We assessed records, conducted structured interviews with heads of facilities, and administered questionnaires to 271 health workers. The study assessed service provision for hypertension, availability of supplies such as medicines, guidelines and equipment, in-service training for hypertension, knowledge of hypertension management, challenges and recommendations. Of the 126 health facilities, 92.9% reported managing (diagnosing/treating) patients with hypertension, and most (80.2%) were run by non-medical doctors or non-physician health workers (NPHW). Less than half (46%) of the facilities had guidelines for managing hypertension. A 10th of the facilities lacked functioning blood pressure devices and 28% did not have stethoscopes. No facilities ever calibrated their BP devices except one. About a half of the facilities had anti-hypertensive medicines in stock; mainly thiazide diuretics (46%), beta blockers (56%) and calcium channel blockers (48.4%). Alpha blockers, mixed alpha & beta blockers and angiotensin II receptor antagonists were only stocked by private clinics/dispensaries. Most HCIIs lacked anti-hypertensive medicines, including the first line thiazide diuretics. Significant knowledge gaps in classification of patients as hypertensive were noted among respondents. All health workers (except 5, 1.9%) indicated that they needed additional training in hypertension management. Several provider and patient related challenges were also observed in this study. Health facilities in this setting are inadequately equipped to provide services for management of hypertension. Diagnostic equipment, anti-hypertensive drugs and personnel present great challenges. To address the increasing burden of hypertension and other chronic diseases, measures are needed to substantially strengthen the healthcare facilities, including training of personnel in management of hypertension and other chronic diseases, and improving diagnostic and treatment supplies.

Task shifting to non-physician clinicians for integrated management of hypertension and diabetes in rural Cameroon: a programme assessment at two years.

PubMed

Labhardt, Niklaus D; Balo, Jean-Richard; Ndam, Mama; Grimm, Jean-Jacques; Manga, Engelbert

2010-12-14

The burden of non-communicable chronic diseases, such as hypertension and diabetes, increases in sub-Saharan Africa. However, the majority of the rural population does still not have access to adequate care. The objective of this study is to examine the effectiveness of integrating care for hypertension and type 2 diabetes by task shifting to non-physician clinician (NPC) facilities in eight rural health districts in Cameroon. Of the 75 NPC facilities in the area, 69 (87%) received basic equipment and training in hypertension and diabetes care. Effectiveness was assessed after two years on status of equipment, knowledge among trained NPCs, number of newly detected patients, retention of patients under care, treatment cost to patients and changes in blood pressure (BP) and fasting plasma glucose (FPG) among treated patients. Two years into the programme, of 54 facilities (78%) available for re-assessment, all possessed a functional sphygmomanometer and stethoscope (65% at baseline); 96% stocked antihypertensive drugs (27% at baseline); 70% possessed a functional glucose meter and 72% stocked oral anti-diabetics (15% and 12% at baseline). NPCs' performance on multiple-choice questions of the knowledge-test was significantly improved. During a period of two years, trained NPCs initiated treatment for 796 patients with hypertension and/or diabetes. The retention of treated patients at one year was 18.1%. Hypertensive and diabetic patients paid a median monthly amount of 1.4 and 0.7 Euro respectively for their medication. Among hypertensive patients with ≥ 2 documented visits (n = 493), systolic BP decreased by 22.8 mmHg (95% CI: -20.6 to -24.9; p < 0.0001) and diastolic BP by 12.4 mmHg (-10.9 to -13.9; p < 0.0001). Among diabetic patients (n = 79) FPG decreased by 3.4 mmol/l (-2.3 to -4.5; p < 0.001). The integration of hypertension and diabetes into primary health care of NPC facilities in rural Cameroon was feasible in terms of equipment and training, accessible in terms of treatment cost and showed promising BP- and FPG-trends. However, low case-detection rates per NPC and a very high attrition among patients enrolled into care, limited the effectiveness of the programme.

A survey of dog and cat anaesthesia in a sample of veterinary practices in New Zealand.

PubMed

Sano, H; Barker, K; Odom, T; Lewis, K; Giordano, P; Walsh, V; Chambers, J P

2018-03-01

To survey current anaesthesia practices for dogs and cats in small and mixed animal practices in New Zealand in order to improve anaesthesia education. A questionnaire was sent to 440 small and mixed animal practices, including questions regarding the type of practice, preanaesthetic examination, anaesthetic drugs and management, anaesthetic machines, monitoring and topics of interest for continuing professional development. Responses were obtained from 113/440 (26%) practices, with 78 (69%) respondents from small and 35 (31%) from mixed animal practices. A preanaesthetic physical examination was carried out by >95% of respondents and premedication was usually given to dogs (112/113; 99%) and cats (95/113; 85%). Acepromazine was the preferred sedative for dogs and cats, with morphine or buprenorphine. Propofol and alfaxalone were the preferred induction agents, and isoflurane was preferred for maintenance in both dogs and cats. A venous catheter was usually placed for anaesthesia in dogs (59/113; 52%), but less so in cats (39/113; 35%). Perioperative fluid was administered at 10 mL/kg/hour by 62/110 (56%) respondents. Intubation was usually used for anaesthesia in dogs (111/112; 99%), and cats (87/112; 78%). Almost 40% of respondents usually administered supplementary oxygen if patients were not intubated. Local analgesia was used by 69/111 (88%) respondents sometimes or always if applicable. Morphine or buprenorphine, and meloxicam were common choices for post-operative analgesia after neuter surgery in dogs and cats. A semiclosed (non-rebreathing) system was used in animals weighing <10 kg, and a Mapleson E or F non-rebreathing circuit was used by 66/109 (61%) practices. Only 15/111 (14%) practices had a ventilator in their practice. A dedicated anaesthetist was usually used by 104/113 (92%) practices, and apnoea alarms, pulse oximeters, thermometers and oesophageal stethoscopes were the main monitoring devices available in practices. Loco-regional block, pain management, and anaesthetic drugs were the main topics of interest for continuing education. Responses by the veterinarians taking part in this survey indicated that they had a reasonably good standard of anaesthetic practice. A physical examination was carried out preanaesthesia, and premedication including analgesia was routinely administered to most patients. A dedicated anaesthetist usually monitored patients and most respondents reported they had access to basic anaesthetic monitoring equipment. Areas where changes could lead to improved anaesthetic practice were increased use of I/V catheterisation, endotracheal intubation, and supplementary oxygen, and reduced I/V fluid rates.

Pediatric hearing aid use: parent-reported challenges.

PubMed

Muñoz, Karen; Olson, Whitney A; Twohig, Michael P; Preston, Elizabeth; Blaiser, Kristina; White, Karl R

2015-01-01

The aim of this study was to investigate parent-reported challenges related to hearing aid management and parental psychosocial characteristics during the first 3 years of the child's life. Using a cross-sectional survey design, surveys were distributed to parents of children with hearing loss via state Early Intervention programs in Utah and Indiana. Packets contained one family demographic form and two sets of three questionnaires to obtain responses from mothers and fathers separately: the Parent Hearing Aid Management Inventory explored parent access to information, parent confidence in performing skills, expectations, communication with the audiologist, and hearing aid use challenges. The Acceptance and Action Questionnaire measured psychological flexibility, experiential avoidance, and internal thought processes that can affect problem-solving ability and decrease an individual's ability to take value-based actions. The Patient Health Questionnaire identified symptoms of depression. Thirty-seven families completed questionnaires (35 mothers and 20 fathers). Most responses were parents of toddlers (M = 22 months) who had been wearing binaural hearing aids for an average of 15 months. Both mothers and fathers reported that even though the amount of information they received was overwhelming, most (84%) preferred to have all the information at the beginning, rather than to receive it over an extended time period. Parents reported an array of challenges related to hearing aid management, with the majority related to daily management, hearing aid use, and emotional adjustment. Sixty-six percent of parents reported an audiologist taught them how to complete a listening check using a stethoscope, however, only one-third reported doing a daily hearing aid listening check. Both mothers and fathers reported a wide range of variability in their confidence in performing activities related to hearing aid management, and most reported minimal confidence in their ability to troubleshoot hearing aid problems. More than half of the parents reported child behavior and activities, such as playing outside, as a major hearing aid use challenge. Parents reported hearing aids were worn all waking hours by 35% of children and less than 5 hr/day by 31%. Almost half of the parents (47%) did not feel that they had enough time to talk about their emotions when speaking with their audiologist(s), 69% reported the audiologist did not help them know what to expect related to emotions about their child's hearing loss, and 22% reported symptoms of depression. Parents reported an array of challenges, even after their child had been wearing hearing aids for a prolonged time, revealing critical implications for how to provide audiological care. Audiologists have an important role in partnering with parents to identify and jointly problem-solving challenges related to their child's hearing aid use. Supporting parents includes not only addressing technical aspects of hearing testing and hearing aid function but also addressing parent thoughts, feelings, and emotions.

Automatic adventitious respiratory sound analysis: A systematic review.

PubMed

Pramono, Renard Xaviero Adhi; Bowyer, Stuart; Rodriguez-Villegas, Esther

2017-01-01

Automatic detection or classification of adventitious sounds is useful to assist physicians in diagnosing or monitoring diseases such as asthma, Chronic Obstructive Pulmonary Disease (COPD), and pneumonia. While computerised respiratory sound analysis, specifically for the detection or classification of adventitious sounds, has recently been the focus of an increasing number of studies, a standardised approach and comparison has not been well established. To provide a review of existing algorithms for the detection or classification of adventitious respiratory sounds. This systematic review provides a complete summary of methods used in the literature to give a baseline for future works. A systematic review of English articles published between 1938 and 2016, searched using the Scopus (1938-2016) and IEEExplore (1984-2016) databases. Additional articles were further obtained by references listed in the articles found. Search terms included adventitious sound detection, adventitious sound classification, abnormal respiratory sound detection, abnormal respiratory sound classification, wheeze detection, wheeze classification, crackle detection, crackle classification, rhonchi detection, rhonchi classification, stridor detection, stridor classification, pleural rub detection, pleural rub classification, squawk detection, and squawk classification. Only articles were included that focused on adventitious sound detection or classification, based on respiratory sounds, with performance reported and sufficient information provided to be approximately repeated. Investigators extracted data about the adventitious sound type analysed, approach and level of analysis, instrumentation or data source, location of sensor, amount of data obtained, data management, features, methods, and performance achieved. A total of 77 reports from the literature were included in this review. 55 (71.43%) of the studies focused on wheeze, 40 (51.95%) on crackle, 9 (11.69%) on stridor, 9 (11.69%) on rhonchi, and 18 (23.38%) on other sounds such as pleural rub, squawk, as well as the pathology. Instrumentation used to collect data included microphones, stethoscopes, and accelerometers. Several references obtained data from online repositories or book audio CD companions. Detection or classification methods used varied from empirically determined thresholds to more complex machine learning techniques. Performance reported in the surveyed works were converted to accuracy measures for data synthesis. Direct comparison of the performance of surveyed works cannot be performed as the input data used by each was different. A standard validation method has not been established, resulting in different works using different methods and performance measure definitions. A review of the literature was performed to summarise different analysis approaches, features, and methods used for the analysis. The performance of recent studies showed a high agreement with conventional non-automatic identification. This suggests that automated adventitious sound detection or classification is a promising solution to overcome the limitations of conventional auscultation and to assist in the monitoring of relevant diseases.

Automatic adventitious respiratory sound analysis: A systematic review

PubMed Central

Bowyer, Stuart; Rodriguez-Villegas, Esther

2017-01-01

Background Automatic detection or classification of adventitious sounds is useful to assist physicians in diagnosing or monitoring diseases such as asthma, Chronic Obstructive Pulmonary Disease (COPD), and pneumonia. While computerised respiratory sound analysis, specifically for the detection or classification of adventitious sounds, has recently been the focus of an increasing number of studies, a standardised approach and comparison has not been well established. Objective To provide a review of existing algorithms for the detection or classification of adventitious respiratory sounds. This systematic review provides a complete summary of methods used in the literature to give a baseline for future works. Data sources A systematic review of English articles published between 1938 and 2016, searched using the Scopus (1938-2016) and IEEExplore (1984-2016) databases. Additional articles were further obtained by references listed in the articles found. Search terms included adventitious sound detection, adventitious sound classification, abnormal respiratory sound detection, abnormal respiratory sound classification, wheeze detection, wheeze classification, crackle detection, crackle classification, rhonchi detection, rhonchi classification, stridor detection, stridor classification, pleural rub detection, pleural rub classification, squawk detection, and squawk classification. Study selection Only articles were included that focused on adventitious sound detection or classification, based on respiratory sounds, with performance reported and sufficient information provided to be approximately repeated. Data extraction Investigators extracted data about the adventitious sound type analysed, approach and level of analysis, instrumentation or data source, location of sensor, amount of data obtained, data management, features, methods, and performance achieved. Data synthesis A total of 77 reports from the literature were included in this review. 55 (71.43%) of the studies focused on wheeze, 40 (51.95%) on crackle, 9 (11.69%) on stridor, 9 (11.69%) on rhonchi, and 18 (23.38%) on other sounds such as pleural rub, squawk, as well as the pathology. Instrumentation used to collect data included microphones, stethoscopes, and accelerometers. Several references obtained data from online repositories or book audio CD companions. Detection or classification methods used varied from empirically determined thresholds to more complex machine learning techniques. Performance reported in the surveyed works were converted to accuracy measures for data synthesis. Limitations Direct comparison of the performance of surveyed works cannot be performed as the input data used by each was different. A standard validation method has not been established, resulting in different works using different methods and performance measure definitions. Conclusion A review of the literature was performed to summarise different analysis approaches, features, and methods used for the analysis. The performance of recent studies showed a high agreement with conventional non-automatic identification. This suggests that automated adventitious sound detection or classification is a promising solution to overcome the limitations of conventional auscultation and to assist in the monitoring of relevant diseases. PMID:28552969

Challenging questions in treating bronchitis.

PubMed

Bode, F R

1998-10-01

Whatever facts we gather and no matter how many we have, you and I must eventually put the journal down and pick up our stethoscope, pen, and prescription pad and go to work. Hopefully we can do better than, "Therapy is not uniform and specific antibiotic regimens are usually selected based on local tribal custom." We can discard an old paradigm, "The absence of data bears no relation to the strength of opinion." Personally, I have used these new scientific data before I reached my conclusion. I have developed 10 points to structure my new approach. I invite you to compare my conclusions to yours. 1. In acute bronchitis, in otherwise healthy adults, my preference is to not prescribe an antibiotic. If I do, it is not over the phone. You should want to see and examine the patient. If there are no helpful hints to etiology, I choose a newer macrolide for those under age 50 and use a short course, five-seven days. For patients over age 50, especially if they are "healthy smokers," consider a short course of cefuroxime. (You can see, even in these acute bronchitis patients, you want an antibiotic effective against today's pathogens.) 2. In all chronic bronchitis patients, prevention of further damage to the airways should be attempted by instituting a program of smoking cessation and appropriate immunizations against influenza and pneumococcus. 3. Treatment outcomes will also improve if we recognize that in some patients the progressing SOB, cough, and increasing sputum production are due to congestive heart failure and not due to infection. I try to think about congestive heart failure in all of my patients, but especially in those with known heart disease and cardiomegaly on their chest x-ray. 4. Routine pulmonary function testing is important in smoking patients. Physicians underestimate the degree of obstruction present when they rely on physical exam alone. Hopefully long before the patient's acute illness you have established whether or not obstruction is present. This information helps identify the high risk patient for not only recurrent bouts of infection but also those at increased risk for lung cancer. 5. We will have more success in treating AECB when we elect to use an antibiotic only for patients with at least two of the following three cardinal symptoms: increased dyspnea, increased sputum production, and increased purulent sputum. COPD patients have many days when they feel more SOB. To use this or any one sign as the sole indication for starting an antibiotic has been proven not to make a statistically significant difference in outcome in most patients. Also, the value of prophylactic antibiotic therapy has not been established. 6. When airflow obstruction is moderately severe or more pronounced, AECB should usually be treated with oral steroids. Other measures such as chronic bronchodilator therapy, supplemental and home oxygen use, and pulmonary rehabilitation have been extensively reviewed elsewhere.

Teaching and testing physical examination skills without the use of patients.

PubMed

Karnath, Bernard; Thornton, William; Frye, Ann W

2002-07-01

To design a cardiopulmonary physical exam curriculum that does not involve the use of patients. Bedside teaching is becoming a lost art, and the use of alternative methods of instruction such as simulation has become increasingly important. Simulators have been shown to enhance physical examination skills of students and physicians in training.(1) In 1995, a program was started to improve cardiopulmonary physical diagnosis and the teaching of auscultation at the University of Texas Medical Branch at Galveston (UTMB). The teaching manikin "Harvey" played a vital role in the development of the new curriculum. In 1997, UTMB adopted an organ-based approach to the basic science curriculum. The cardiopulmonary module in the basic science curriculum was a ten-week course taught in the second year of medical school. The physical diagnosis section of that course involved six instructional hours; four of the six hours were dedicated to cardiac auscultation and two hours to pulmonary auscultation. Only simulators and CD-ROMs were used for instruction. The 184 second-year medical students at UTMB were formed into small groups for instruction and practice. Although "Harvey" was an effective teaching tool, other simulators had to be developed for testing students' skills after instruction. It would be very difficult to administer a skills OSCE for 184 students without the development of several smaller transportable simulators. A commercially available blood pressure simulator from the Medical Plastics Laboratory, Inc., Gatesville, TX, was used to test the accuracy of students' blood pressure readings. Small auscultation transducers combined with a palpable pulse simulator, developed by one of the authors (WT) in collaboration with Andries Acoustics, Spicewood, TX, were used to efficiently test students' proficiency in cardiopulmonary auscultation. Digital simulated cardiopulmonary sounds were recorded onto a standard CD-ROM mini-disc and transmitted to the small transducers. Students used their own stethoscopes for auscultation. The targeted skills were efficiently tested in one hour of testing time per student. This cardiopulmonary instructional module was well received by the second-year medical students. In the skills OSCE, 80% of the students accurately measured systolic and diastolic blood pressure to within 5 mm Hg. Cardiopulmonary auscultation proficiency results showed average recognition of 60% for cardiac abnormalities and 88% for pulmonary sounds. Developing auscultation transducers with pulse simulation capability ensured that students could identify systole. Therefore, heart murmurs and sounds could be timed with the cardiac cycle. We found the results from the skills OSCE encouraging. Most students demonstrated reasonable competency in the skills taught, and the new transportable simulators performed well. The six-hour instructional module was meant to prepare students for their bedside teaching during the third year of medical school. The significant cost of the "Harvey" simulator may be a barrier to its widespread use for teaching. Therefore, continued development of smaller transportable simulators for teaching and testing purposes is important.

Accuracy and reliability of wrist-cuff devices for self-measurement of blood pressure.

PubMed

Kikuya, Masahiro; Chonan, Kenichi; Imai, Yutaka; Goto, Eiji; Ishii, Masao

2002-04-01

Self-measurement of blood pressure (BP) might offer some advantages in diagnosis and therapeutic evaluation and in patient management of hypertension. Recently, wrist-cuff devices for self-measurement of BP have gained more than one-third of the world market share. In the present study, we validated wrist-cuff devices and compared the results between wrist- and arm-cuff devices. The factors affecting the accuracy of wrist-cuff devices were also studied. The research group to assess the validity of automated blood pressure measuring device consisted of 13 institutes in Japan, which validated two wrist-cuff devices (WC-1 and WC-2) and two arm-cuff devices (AC-1 and AC-2). They used a crossover method, where the comparison was done between auscultation, by two observers by means of a double stethoscope on one arm and the device on the opposite arm or wrist. There was good inter-observer agreement for the auscultation method in each institute (systolic blood pressure (SBP), -0.1 +/- 2.8 mmHg; diastolic blood pressure (DBP), -0.1 +/- 2.6 mmHg, n = 498). The mean difference between auscultation and the device was minimal both in arm-cuff devices (mean difference for AC-1, 2.2/1.9 mmHg, n = 97 and for AC-2, 5.1/2.9 mmHg, n = 136, SBP/DBP) and wrist-cuff devices (mean difference for WC-1, -2.1/1.2 mmHg, n = 173 mmHg and for WC-2, -2.3/-5.6 mmHg, n = 92). The standard deviation of the difference (SDD) in wrist-cuff devices, however (SDD for WC-1, 9.7/7.3 mmHg and for WC-2, 10.2/8.6 mmHg), was larger than that of the arm-cuff devices (SDD for AC-1, 5.6/6.6 mmHg and for AC-2, 6.3/5.1 mmHg). Grading of AC-1 and AC-2 based on criteria of British Hypertension Society was A/A and B/A, respectively, while that of WC-1 and WC-2 was C/B and D/B, respectively. Using the same validation protocol, the results of validation for one device were divergent in each institute. In wrist-cuff devices, the BP value obtained in palmar flexion was significantly higher and that obtained in palmar dorsiflexion was significantly lower than that in palmar extension. In some cases, finger plethysmogram did not disappear during maximum inflation of the wrist-cuff (congruent with 250 mmHg), even in palmar extension and especially in palmar flexion, suggesting incomplete obstruction of radial and/or ulnar arteries during inflation. The results suggest that wrist-cuff devices in the present form are inadequate for self-measurement of blood pressure and, thus, are inadequate for general use or clinical and practical use. However, there is much possibility in wrist-cuff device and the accuracy and reliability of wrist-cuff device are warranted by an improvement of technology.

[Infrared temperature measurement in the ear canal with the DIATEK 9000 Instatemp and the DIATEK 9000 Thermoguide. Comparison with methods of temperature measurement in other body parts].

PubMed

Fritz, U; Rohrberg, M; Lange, C; Weyland, W; Bräuer, A; Braun, U

1996-11-01

Temperature of the tympanic membrane is recommended as a "gold standard" of core-temperature recording. However, use of temperature probes in the auditory canal may lead to damage of tympanic membrane. Temperature measurement in the auditory canal with infrared thermometry does not pose this risk. Furthermore it is easy to perform and not very time-consuming. For this reason infrared thermometry of the auditory canal is becoming increasingly popular in clinical practice. We evaluated two infrared thermometers-the Diatek 9000 Thermoguide and the Diatek 9000 Instatemp-regarding factors influencing agreement with conventional tympanic temperature measurement and other core-temperature recording sites. In addition, we systematically evaluated user dependent factors that influence the agreement with the tympanic temperature. In 20 volunteers we evaluated the influence of three factors: duration of the devices in the auditory canal before taking temperature (0 or 5 s), interval between two following recordings (30, 60, 90, 120, 180 s) and positioning of the grip relative to the auditory-canal axis (0, 60, 180 and 270 degrees). Agreement with tympanic contact probes (Mon-a-therm tympanic) in the contralateral ear was investigated in 100 postoperative patients. Comparative readings with rectal (YSI series 400) and esophageal (Mon-a-therm esophageal stethoscope with temperature sensor) probes were done in 100 patients in the ICU. The method of Bland and Altman was taken for comparison. Shortening of the interval between two consecutive readings led to increasing differences between the two measurements with the second reading decreasing. A similar effect was seen when positioning the infrared thermometers in the auditory canal before taking temperatures: after 5 s the recorded temperatures were significantly lower than temperature recordings taken immediately. Rotation of the devices out of the telephone handle position led to increasing lack of agreement between infrared thermometry and contact probes. Mean differences between infrared thermometry (Instatemp and Thermoguide, CAL-Mode) and tympanic probes were -0.41 +/- 0.67 degree C (2 SD) and -0.43 +/- 0.70 degree C, respectively. Mean differences between the Thermoquide (Rectal-Mode) and rectal probe were -0.19 +/- 0.72 degree C, and between the Thermoguide (Core Mode) and esophageal probe -0.13 +/- 0.74 degree C. Although easy to use, infrared thermometry requires careful handling. To obtain optimal recordings, the time between two consecutive readings should not be less than two min. Recordings should be taken immediately after positioning the devices in the auditory canal. Best results are obtained in the 60 degrees position with the grip of the devices following the ramus mandibulae (telephone handle position). The lower readings of infrared thermometry compared with tympanic contact probes indicate that the readings obtained represent the temperature of the auditory canal rather than of the tympanic membrane itself. To compensate for underestimation of core temperature by infrared thermometry, the results obtained are corrected and transferred into core-equivalent temperatures. This data correction reduces mean differences between infrared recordings and traditional core-temperature monitoring, but leaves limits of agreement between the two methods uninfluenced.

Chronicle of a Death Foretold

NASA Astrophysics Data System (ADS)

2007-05-01

Using ESO's VLTI on Cerro Paranal and the VLBA facility operated by NRAO, an international team of astronomers has made what is arguably the most detailed study of the environment of a pulsating red giant star. They performed, for the first time, a series of coordinated observations of three separate layers within the star's tenuous outer envelope: the molecular shell, the dust shell, and the maser shell, leading to significant progress in our understanding of the mechanism of how, before dying, evolved stars lose mass and return it to the interstellar medium. S Orionis (S Ori) belongs to the class of Mira-type variable stars. It is a solar-mass star that, as will be the fate of our Sun in 5 billion years, is nearing its gloomy end as a white dwarf. Mira stars are very large and lose huge amounts of matter. Every year, S Ori ejects as much as the equivalent of Earth's mass into the cosmos. ESO PR Photo 25a/07 ESO PR Photo 25a/07 Evolution of the Mira-type Star S Orionis "Because we are all stardust, studying the phases in the life of a star when processed matter is sent back to the interstellar medium to be used for the next generation of stars, planets... and humans, is very important," said Markus Wittkowski, lead author of the paper reporting the results. A star such as the Sun will lose between a third and half of its mass during the Mira phase. S Ori pulsates with a period of 420 days. In the course of its cycle, it changes its brightness by a factor of the order of 500, while its diameter varies by about 20%. Although such stars are enormous - they are typically larger than the current Sun by a factor of a few hundred, i.e. they encompass the orbit of the Earth around the Sun - they are also distant and to peer into their deep envelopes requires very high resolution. This can only be achieved with interferometric techniques. ESO PR Photo 25b/07 ESO PR Photo 25b/07 Structure of S Ori (Artist's Impression) "Astronomers are like medical doctors, who use various instruments to examine different parts of the human body," said co-author David Boboltz. "While the mouth can be checked with a simple light, a stethoscope is required to listen to the heart beat. Similarly the heart of the star can be observed in the optical, the molecular and dust layers can be studied in the infrared and the maser emission can be probed with radio instruments. Only the combination of the three gives us a more complete picture of the star and its envelope." The maser emission comes from silicon monoxide (SiO) molecules and can be used to image and track the motion of gas clouds in the stellar envelope roughly 10 times the size of the Sun. The astronomers observed S Ori with two of the largest interferometric facilities available: the ESO Very Large Telescope Interferometer (VLTI) at Paranal, observing in the near- and mid-infrared, and the NRAO-operated Very Long Baseline Array (VLBA), that takes measurements in the radio wave domain. Because the star's luminosity changes periodically, the astronomers observed it simultaneously with both instruments, at several different epochs. The first epoch occurred close to the stellar minimum luminosity and the last just after the maximum on the next cycle. ESO PR Photo 25c/07 ESO PR Photo 25c/07 S Ori to Scale (Artist's Impression) The astronomers found the star's diameter to vary between 7.9 milliarcseconds and 9.7 milliarcseconds. At the distance of S Ori, this corresponds to a change of the radius from about 1.9 to 2.3 times the distance between the Earth and the Sun, or between 400 and 500 solar radii! As if such sizes were not enough, the inner dust shell is found to be about twice as big. The maser spots, which also form at about twice the radius of the star, show the typical structure of partial to full rings with a clumpy distribution. Their velocities indicate that the gas is expanding radially, moving away at a speed of about 10 km/s. The multi-wavelength analysis indicates that near the minimum there is more dust production and mass ejection: in these phases indeed the amount of dust is significantly higher than in the others. After this intense matter production and ejection the star continues its pulsation and when it reaches the maximum luminosity, it displays a much more expanded dust shell. This clearly supports a strong connection between the Mira pulsation and the dust production and expulsion. Furthermore, the astronomers found that grains of aluminum oxide - also called corundum - constitute most of S Ori's dust shell: the grain size is estimated to be of the order of 10 millionths of a centimetre, that is one thousand times smaller than the diameter of a human hair. "We know one chapter of the secret life of a Mira star, but much more can be learned in the near future, when we add near-infrared interferometry with the AMBER instrument on the VLTI to our (already broad) observational approach," said Wittkowski. More Information The research presented here is reported in a paper in press in the journal Astronomy and Astrophysics ("The Mira variable S Ori: Relationships between the photosphere, molecular layer, dust shell, and SiO maser shell at 4 epochs", by M. Wittkowski et al.). It is available in PDF format from the publisher's web site. The team consists of Markus Wittkowski (ESO), David A. Boboltz (U.S. Naval Observatory, USA), Keiichi Ohnaka and Thomas Driebe (MPIfR Bonn, Germany), and Michael Scholz (University of Heidelberg, Germany and University of Sydney, Australia).

VLBA Teams With Optical Interferometer to Study Star's Layers

NASA Astrophysics Data System (ADS)

2007-05-01

Two of the World's Largest Interferometric Facilities Team-up to Study a Red Giant Star Using ESO's VLTI on Cerro Paranal and the VLBA facility operated by NRAO, an international team of astronomers has made what is arguably the most detailed study of the environment of a pulsating red giant star. They performed, for the first time, a series of coordinated observations of three separate layers within the star's tenuous outer envelope: the molecular shell, the dust shell, and the maser shell, leading to significant progress in our understanding of the mechanism of how, before dying, evolved stars lose mass and return it to the interstellar medium. S Orionis (S Ori) belongs to the class of Mira-type variable stars. It is a solar-mass star that, as will be the fate of our Sun in 5 billion years, is nearing its gloomy end as a white dwarf. Mira stars are very large and lose huge amounts of matter. Every year, S Ori ejects as much as the equivalent of Earth's mass into the cosmos. ESO PR Photo 25a/07 ESO PR Photo 25a/07 Evolution of the Mira-type Star S Orionis "Because we are all stardust, studying the phases in the life of a star when processed matter is sent back to the interstellar medium to be used for the next generation of stars, planets... and humans, is very important," said Markus Wittkowski, lead author of the paper reporting the results. A star such as the Sun will lose between a third and half of its mass during the Mira phase. S Ori pulsates with a period of 420 days. In the course of its cycle, it changes its brightness by a factor of the order of 500, while its diameter varies by about 20%. Although such stars are enormous - they are typically larger than the current Sun by a factor of a few hundred, i.e. they encompass the orbit of the Earth around the Sun - they are also distant and to peer into their deep envelopes requires very high resolution. This can only be achieved with interferometric techniques. ESO PR Photo 25b/07 ESO PR Photo 25b/07 Structure of S Ori (Artist's Impression) "Astronomers are like medical doctors, who use various instruments to examine different parts of the human body," said co-author David Boboltz. "While the mouth can be checked with a simple light, a stethoscope is required to listen to the heart beat. Similarly the heart of the star can be observed in the optical, the molecular and dust layers can be studied in the infrared and the maser emission can be probed with radio instruments. Only the combination of the three gives us a more complete picture of the star and its envelope." The maser emission comes from silicon monoxide (SiO) molecules and can be used to image and track the motion of gas clouds in the stellar envelope roughly 10 times the size of the Sun. The astronomers observed S Ori with two of the largest interferometric facilities available: the ESO Very Large Telescope Interferometer (VLTI) at Paranal, observing in the near- and mid-infrared, and the NRAO-operated Very Long Baseline Array (VLBA), that takes measurements in the radio wave domain. Because the star's luminosity changes periodically, the astronomers observed it simultaneously with both instruments, at several different epochs. The first epoch occurred close to the stellar minimum luminosity and the last just after the maximum on the next cycle. ESO PR Photo 25c/07 ESO PR Photo 25c/07 S Ori to Scale (Artist's Impression) The astronomers found the star's diameter to vary between 7.9 milliarcseconds and 9.7 milliarcseconds. At the distance of S Ori, this corresponds to a change of the radius from about 1.9 to 2.3 times the distance between the Earth and the Sun, or between 400 and 500 solar radii! As if such sizes were not enough, the inner dust shell is found to be about twice as big. The maser spots, which also form at about twice the radius of the star, show the typical structure of partial to full rings with a clumpy distribution. Their velocities indicate that the gas is expanding radially, moving away at a speed of about 10 km/s. The multi-wavelength analysis indicates that near the minimum there is more dust production and mass ejection: in these phases indeed the amount of dust is significantly higher than in the others. After this intense matter production and ejection the star continues its pulsation and when it reaches the maximum luminosity, it displays a much more expanded dust shell. This clearly supports a strong connection between the Mira pulsation and the dust production and expulsion. Furthermore, the astronomers found that grains of aluminum oxide - also called corundum - constitute most of S Ori's dust shell: the grain size is estimated to be of the order of 10 millionths of a centimetre, that is one thousand times smaller than the diameter of a human hair. "We know one chapter of the secret life of a Mira star, but much more can be learned in the near future, when we add near-infrared interferometry with the AMBER instrument on the VLTI to our (already broad) observational approach," said Wittkowski. More Information The research presented here is reported in a paper in press in the journal Astronomy and Astrophysics ("The Mira variable S Ori: Relationships between the photosphere, molecular layer, dust shell, and SiO maser shell at 4 epochs", by M. Wittkowski et al.). It is available in PDF format from the publisher's web site. The team consists of Markus Wittkowski (ESO), David A. Boboltz (U.S. Naval Observatory, USA), Keiichi Ohnaka and Thomas Driebe (MPIfR Bonn, Germany), and Michael Scholz (University of Heidelberg, Germany and University of Sydney, Australia). Notes A maser is the microwave equivalent to a laser, which emits visible light. A maser emits powerful microwave radiation instead and its study requires radio telescopes. An astrophysical maser is a naturally occurring source of stimulated emission that may arise in molecular clouds, comets, planetary atmospheres, stellar atmospheres, or from various conditions in interstellar space. ESO operates the Very Large Telescope Interferometer at Paranal Observatory, Chile, with four fixed 8.2-m telescopes and four relocatable 1.8-m telescopes, working at optical/infrared wavelengths. NRAO operates the Very Long Baseline Array with 10 stations across the U.S. working at radio wavelengths between 3 mm and 90 cm (0.3-90 GHz). ESO, NRAO and other partners will operate the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, working at millimetre wavelengths between 0.3 and 10 mm (30-950 GHz)

Houston, We Have a Podcast. Episode 22: Astronaut Health

NASA Image and Video Library

2017-12-07

[00:00:00] Gary Jordan (Host): Houston, we have a podcast! Welcome to the official podcast of the NASA Johnson Space Center, Episode 22, Astronaut Health. I'm Gary Jordan, and I'll be your host today. So on this podcast, we bring in the experts, NASA scientists, engineers, astronauts, all the coolest people! We bring them right here on the show to tell you about more everything NASA. So today, we're talking about astronaut health with Natacha Chough. She's a flight surgeon here at the NASA Johnson Space Center in Houston, Texas, and she gave a great description about what a flight surgeon does and how they work with astronauts to monitor their health during spaceflight. So thanks to future doctor spaceman for the suggestion on Twitter for an episode with a flight surgeon. If you have suggestions for the topic you'd like to hear on the show, let us know! You can find where to submit everything at the end of every episode. No, I'm not going to reveal it right up front, you got to listen to the whole thing. Plus, this is a really good conversation anyway. You're going to really enjoy it. So, with no further delay, let's go lightspeed and jump right ahead to our talk with Dr. Natacha Chough. Enjoy! [00:00:59] [ Music ] [00:01:12] [ Music & Radio Transmissions ] [00:01:18] [ Music ] Host: Now, we'll -- we'll start with something happy. Natasha, thanks so much for coming on the show, ran into your profile as part of Peggy's NASA Village Project, you're one of the many people that supported Peggy Whitson, right, during her flight. So how was it -- what was it like working with the space ninja? [00:01:36] Natacha Chough: So I think as anyone who works with Peggy will tell you, she is awesome at what she does! [Laughing] And she's just a joy to watch. Plus she's a wonderful person, which just makes it even better. [00:01:46] Host: Oh yeah. Yeah, definitely. Just in the few interactions I've had with her where, you know, interviews or her dealing with media, just, you know, sitting down in the chair with a lot of people looking at her, lights, cameras, and she's just laughing, having a good time. It's just, you know, you really appreciate that when you're on -- when you're on the behind-the-scenes stuff and you know the pressure that goes into it. But you were -- for supporting her, you're a flight surgeon, right? [00:02:07] Natacha Chough: So I wasn't assigned to her as her crew surgeon, but I was -- after her landing, her in two fish [phonetic], I was the physician on the NASA aircraft that brought them back to Houston. [00:02:19] Host: Oh, okay. So you were out -- you were out in Kazakhstan then? [00:02:23] Natacha Chough: So, actually, this landing happened right after Harvey, and because of the multiple personnel impacts that NASA had, including to our aircraft operations division, we weren't able to get our aircraft staged in Kazakhstan in time for their landing. So, what happened was we got the help from the European Space Agency, so they had an aircraft and they went and got our crew in Kazakhstan and brought them back to Cologne, Germany, use the headquarters, and then we went to Cologne to pick up our crew there. [00:02:52] Host: Okay. [00:02:52] Natacha Chough: So that was like a total modified... [00:02:54] Host: Yeah! [00:02:55] Natacha Chough: ...expected direct return operation, yeah. [00:02:57] Host: So you went from Houston to Germany then? Okay. And you were -- so you were -- so what is -- what is that? What's a doctor on-call? [00:03:04] Natacha Chough: We call it the air doc. [00:03:07] Host: Air doc. [00:03:07] Natacha Chough: Yeah. So NASA has an aircraft that we use to bring back our crew from landing within 24 hours, and the -- the purpose of that is just so the science and research folks can get data as soon as possible once the crew returned, just because there's a lot of physiologic changes that happen. You know, not only right after landing, but in the -- the hours and days that follow. [00:03:30] Host: Okay, yeah, and you have to just kind of -- so, what's your job? Your job is to monitor it, record it, to help it? [00:03:36] Natacha Chough: We do take some samples and stuff in flight on return, but, you know, the crew can be pretty symptomatic in terms of like returning to a 1G environment, and so we kind of mitigate a lot of the symptoms that they're having, motion sickness, that type of thing, in the early hours, post-landing. [00:03:54] Host: So now you're a -- you're a flight surgeon now, right? Who's your crew members that you're working with? [00:03:59] Natacha Chough: So currently I'm assigned to Jeanette Epps, and she's launching next spring. [00:04:03] Host: Okay. Okay. So you -- what's some of the stuff you have to do this early ahead of time? [00:04:08] Natacha Chough: So right now, we just did her L minus 6 months physical, make sure that, you know, she's still within standards for long duration spaceflight. She's actually out of the country right now because in this part of the pre-launch timeframe, she and Alex [inaudible], he's a crew member, and then Sergei [inaudible], the Russian crew member, they're all serving as the backup crew to the prime crew that's launching this December. [00:04:33] Host: Oh, okay. So they're out there with Scott Tingle and [inaudible] and those guys? Okay, cool. Very cool. So you're -- you don't have to follow them for that then? You get to stay here? [00:04:43] Natacha Chough: Yeah. In the meantime, you know, there's a lot of just like pre-travel prep, making sure all of us, including the docs, are up on our immunizations for, you know, upcoming travel. In the next few months before launch, we'll also get together with her in our pharmacy, and make sure that she's got any prescription meds she takes on a regular basis put in these ISS medical accessory packs, people take, you know, nutritional supplements or daily vitamins or whatever, we make sure that all that is packed for them and any motion sickness meds they might need on the way up. [00:05:13] Host: Okay. So how long have you been in the flight director, or not flight director, flight surgeon role? [00:05:18] Natacha Chough: So I got hired on full-time here a little over two and a half years ago. [00:05:22] Host: Okay, cool. Alright. So let's -- let's back up just a little bit from -- from all this and talk about, what is a flight surgeon? Right? Let's start -- let's do that. [00:05:32] Natacha Chough: Yeah, so I got to tell you it is the coolest, yet most misleading job title there is, because we don't fly in space, and the vast -- vast majority of us aren't actual surgeons. What a flight surgeon is is a medical doctor who takes care of pilots and astronauts. But the job title is a total misnomer, it's kind of like -- I think of like the surgeon general of the United States, right? So most of these aren't actual surgeons. So for those who are listening who aren't military buffs, basically, dating back to like early wars, actual surgeons were the predominant type of medical doctor on the battlefield, and then that term has stuck in the military at NASA. And the flight part of the job title indicates, you know, that we take care of pilots and astronauts, but it also implies that we have at least some flying experience ourselves, either as private pilots, student pilots, or, you know, riding in the backseat of the T38, the NASA training jet, along with our crew members. So, that flight experience is actually key to understanding the physiology of the flight environment that our patients experience, as well as the psychology and the human factor aspect of like how they interface with engineering design and aircraft controls, and all that's especially important for maintaining crew safety. [00:06:42] Host: How about that? So what are some of the main differences then? Like what -- what separates, you know, what makes you have that flight thing? What are some of the considerations whenever I guess the human body is in flight? [00:06:54] Natacha Chough: Right. So, in flight, depending on the different types of maneuvers you're going to be doing, like if you've been to an airshow, aerobatic pilots can do, you know... [00:07:04] Host: Crazy stuff! [00:07:04] Natacha Chough: A lot of [inaudible] maneuvers, and depending on the order in which they do them, it can change, you know, blood rushing to your head versus blood rushing to your feet, and if you do that [laughing] in a very provocative way, you run the risk of what pilots refer to as graying out or blacking out and losing consciousness momentarily. So you never want those types of incapacitating events to happen in flight. And that's what we try to prevent. Another big thing that we learn about is hypoxia, right, so lack of oxygen. And so if you're cabin, for whatever reason, depressurizes and you are, you know, at the equivalent of tens of hundreds of feet, you know, above sea level, that's going to feel a lot different than a cabin that's pressurized to a more normal environment. So our regular aircraft that all of us fly commercially, like a Southwest aircraft, for example, is pressurized to 8,000 feet and most of us can tolerate that, but if you have a depressurization and all of a sudden you're at the equivalent of 30,000 feet, obviously, your time of useful consciousness, or the amount of time it's going to take before you pass out because you -- there's not enough oxygen up there at that altitude is, you know, goes down to seconds. [00:08:13] Host: Wow. [00:08:14] Natacha Chough: So those are the types of things that we have to learn about, and then, you know, we train along with crew to understand what our particular symptoms are in that situation, because it can be a little bit different for different people. Some people get a little bit loopy. Some people have spotty vision, some people get shaky, it really depends. [00:08:31] Host: Oh yeah, there's -- is that -- is it hypobaric chamber? [00:08:36] Natacha Chough: Hypobaric. Yep. [00:08:37] Host: Hypobaric, where they actually -- they'll do that, right? [00:08:39] Natacha Chough: Exactly. [00:08:40] Host: You go in there, they'll bring down the pressure, and they'll just like watch you and then write down some stuff. I actually had a friend that did that. She works in the MBL, and hers was actually -- she said she -- nothing happened to her. And I was like, oh, that's cool, and she's like, no. [00:08:55] Natacha Chough: That's actually bad. [00:08:56] Host: Yeah! Exactly! And it's because, right, you need to think about your symptoms. [00:09:00] Natacha Chough: Right. And if you don't have any symptoms, you could pass out like that, and we never want that to happen when you're at the controls of an aircraft or, you know, if you're on an EVA and that happens for whatever reason. [00:09:12] Host: Okay. So, do you understand -- when you're a flight surgeon, you understand the -- what happens for your -- the crew members that you're taking care of? [00:09:21] Natacha Chough: Right. And another thing that they do in training is a CO2 exposure class. So carbon dioxide is different on station than it is on earth, right? The levels are different. Because here on earth, if a room gets stuffy, we can just open the window, you can't really do that on station. So, crew are exposed to about 8 minutes of carbon dioxide. It's basically they're breathing into a bag and they're rebreathing their -- their own expired air during these 8 minutes. And they write down their symptoms for that, as well. And that's really important because if levels tend to creep up on station, they have an idea, from this exposure class, you know, what their symptoms are and whether it's potentially attributable to the CO2 levels on station. [00:10:06] Host: Wow. There's a lot of tests for [laughter] being a flight surgeon where they just put you through the ringer! Alright, well, we're going to deprive you of like pressure and see what happens. Alright, keep breathing your own CO2, see what happens. What other kind of tests are like that? [00:10:19] Natacha Chough: Well, I've definitely done the hypobaric -- hypobaric chamber, you know, hypoxia demonstration more times than I can count now. So I think I've lost enough brain cells at this point, but, you know, a lot of it too is -- is written tests and stuff as you're going through like medical specialty training, so. [00:10:34] Host: Okay. Because I know like they -- they do egress training for -- I've seen the ones for Orion, I think, where they actually jump in and I don't know if there's some health considerations there for where a flight surgeon would be for that test. [00:10:46] Natacha Chough: There are. So, you know, Orion is supposed to splash down in the water, and after you've been in space for a long time, that rocking motion in the spacecraft can be really provocative when you're already motion sick, and so, you know, there's certain parameters as to how much rocking we would like versus -- versus not, and, you know, what all that is going to look like. So, people way smarter than me are working on that. [00:11:10] Host: [Laughing] So, when you're -- when you're assigned a crew member, what -- at what point do you start working with them, and at what point do you kind of say, you're done, and you kind of can go onto the next crew member or something? [00:11:22] Natacha Chough: So we usually get assigned to them about a year in advance or so. [00:11:26] Host: Okay. Of their launch? [00:11:28] Natacha Chough: Of their launch. Yeah. It can be as soon as like -- as early as 18 months pre-launch. And so it definitely ramps up like exponentially the closer you get to launch. Like I mentioned, if, you know, if you're in Star City is the physician and you're supporting them through some of the Russian medical training that they do there, when they're here doing training in the MBL, the MBL during their suited run, we also support their vacuum chamber runs in Building 7, which is where they test their AVA suit and make sure that it functions at vacuum. And then there's, on the medical side, there's actually a lot of medical training that they crew get, because there's no requirement right now that there's a physician on station, but each expedition is assigned to CMOs, or chief medical officers, and those are US OS crew members who have a little bit of additional medical training, and so that can include, you know, putting in stitches or temporary dental fillings if needed, those types of things. [00:12:32] And so we've got -- we work with really talented nurses who help train our crew on how to draw their own blood, how to start IVs, all that type of thing. [00:12:40] Host: Oh, okay. And a lot of them are doing studies like that, just normally, right? [00:12:44] Natacha Chough: Some of it is research-based. [00:12:45] Host: Some research-based stuff, I guess besides the medical side, but, okay. So then you -- if they -- if there's no physician on the station, the backup is to have a physician on the ground, right? That's the -- that's the normal way of doing things, and flight surgeons sit in mission control. So is that part -- like, how often are you doing that? [00:13:05] Natacha Chough: So, when you're assigned to a mission, you're on counsel a few times out of the week and -- and that's only because you rotate with other crew surgeons who are working that same expedition. [00:13:16] Host: Oh, okay. So, you're -- it's not just you, it's like a team. [00:13:18] Natacha Chough: It's like a team of 4. Right? So like each Soyuz launch, on the NASA side at least, has one prime crew surgeon and one deputy crew surgeon who's their backup, essentially. And then it's usually two Soyuz crews at a time, and so that's what makes up the -- the four docs that kind of rotate sitting in console. [00:13:35] Host: There you go. So what are you looking at when you're on console? [00:13:38] Natacha Chough: So on console, on a regular day, we mostly focus on the -- the station, what we call the bio environmentals. I like to call it the vital signs on station. Right, so like, what's the CO2 level today? Like what's the pressure, you know, in the modules that the crew is working in, what's the O2 level? What's the temperature? What's the humidity? And then we look at their timeline everyday, so as you probably know, the schedule for each crew member is planned out to like 5 minute increments. [00:14:06] Host: Oh yeah. [00:14:07] Natacha Chough: So, there's always reviews of plans for, you know, the current day, one day out, three days out, seven days out, and so we're just verifying to make sure that, you know, everyone's got two hours of exercise blocked off that, you know, on most days, unless there's an extenuating circumstance, everyone's eating lunch together, because that's really good for, you know, crew psychology, and then making sure that there's nothing, you know, that's unnecessarily interrupting sort of their wind-down period at the end of the day before they go to sleep. It's kind of like if you got called about something for work at like 9 o'clock at night. You know what I mean? So, we try and like really minimize that kind of thing, and then, overall, we also have to approve any overages to their kind of weekly duty hours to make sure that they're not, you know, at risk of bringing out for like working too long of a week, and so if -- if that ever happens, we have weekly meetings with the flight director to make sure that that time is made up the following week, if they get a day off or some time off, subsequently. [00:15:06] Host: So you must be really close with the astronauts then, because you're the one that actually protects them from working. [00:15:10] Natacha Chough: Yeah, so, I mean, yeah, the role of the flight doc these days, you know, back in World War I when flight docs were started, I feel like there was a little bit of animosity, right? [Laughing] Like between flight docs and -- and military fliers, because, you know, the best that you could ever do is come out even from an employment with your flight doc. You know, the worst that you could come out is that they would ground you for some medical reason, but these days it's a lot more -- we're definitely their advocate, right, and want to make sure that we create an environment that is conducive of them, you know, flying happily and safely and healthily. [00:15:46] Host: Yeah. I mean, what -- what is -- what does a flight surgeon do to make sure that they are in a state of mind where they can perform hundreds of experiments and -- and do all the tasks that are assigned to them on a daily basis? [00:15:58] Natacha Chough: So that's actually something that our behavioral health and performance group focuses on, and we work in consultation with them, but, essentially, we've got crew psychologists and crew psychiatrists that are assigned to each crew member, and then, you know, before their mission, they meet with them on a regular basis, and then during the mission, they have what they call PPCs, or private psychological conferences every couple of weeks, and those docs also will be in touch with the crew member's family. Especially after events like Harvey, right? Something totally unplanned and that can be a huge stressor for -- for folks on orbit and their family members on the ground. [00:16:40] Host: Oh, yeah. [00:16:40] Natacha Chough: Yeah. So, they're very good about, you know, before astronauts are even selected, like screening for people who are psychologically, you know, very stable. Once they're selected, making sure that they have all the resources that they have pre-mission, during mission, they talk about, you know, if there's bad news, how do you want it to be delivered? Who do you want to deliver the news? How do you want them to deliver it? So, that group is really, I think, paramount to crew well-being, and then keeping the family members in the loop as well with regular communication. [00:17:14] Host: So that's -- that's just not flight surgeon job then, is it? [00:17:17] Natacha Chough: No, it's more -- yeah, it's BHP. [00:17:19] Host: BHP. Yeah, exactly. What -- what qualifies an astronaut as being able to go to space, medically, healthy? [00:17:26] Natacha Chough: So, what we look for is overall medical fitness for the pressures of spaceflight, and that begins, like I mentioned, with, you know, selection criteria during the application process. So once they're selected, if they have an illness or an injury, we get them treatment and the specialty care that they need, and then we have an air medical board that actually reviews their case files on a regular basis to recertify them for flight if they happen to be grounded for whatever reason. It's actually similar to how the military and the FAA medically certify their pilots. And as a taxpayer, for those of you listening out there, so these processes are also in existence to help keep the general public safe. So, in general, the FAA has a role to keep the risk of a pilot having an incapacitating medical event to less than 1 percent. [00:18:15] Host: Alright. [00:18:17] Natacha Chough: So, we kind of follow very similar standards. But in order for crew to stay healthy, essentially, they have to train, right? So, like I mentioned, we work with really talented physical trainers, psychiatrists, psychologists, pharmacists, nurses, to make sure that our crew are not only physically and mentally ready for long-duration spaceflight, but they're also capable to administer medical care to each other if necessary. [00:18:45] Host: Okay, are you overseeing their -- their workouts and stuff like that? Or is that a totally different thing? [00:18:50] Natacha Chough: So that's the job of our ACERS, so those are astronaut strength, conditioning, and rehab specialists, it's their personal trainers, essentially. So when crew go to orbit, they are actually given what we call an exercise prescription. And they've got different goals that they can work towards and -- and modify if needed in space, and all of that, essentially, is part of our -- it's actually I think one of our most successful countermeasures, right, is maintaining your bone and muscle mass. So we know that maintaining your muscle mass with resistive exercises and getting some sort of impact exercise, like on the treadmill, is really helpful in preventing bone loss and muscle weakness post-flight. [00:19:30] Host: Yeah, definitely. What about -- you said there was a pharmaceutical component to there, are they making sure that they get doses of certain medicines to stay healthy? Like, I don't know if they do calcium supplements or something like that? [00:19:41] Natacha Chough: So, we actually, yeah, we have a great pharmacy here at JSC, and pharmacy helps pack any, you know, regular prescription meds that people fly with, and in addition, you know, they can let us know, there's been some research, there hasn't been enough, but, you know, certain meds just don't do well in space for reasons that we still don't completely understand. So, some -- some medications, if they're in liquid form, will bubble or foam too much to be of any use in space. It's harder to draw them up in a syringe, because you don't have that air -- same air, fluid separation that you do with gravity. So we can't fly those meds, because it's -- it wouldn't be useful. [00:20:19] Host: Right, but they're probably meds that you would need, right? So is there a workaround? [00:20:24] Natacha Chough: So there are alternative meds that we can fly instead, in the meantime, and then we also have medical kits on station with Tylenol and ibuprofen and things like that, if people happen to -- to need those during their mission. [00:20:34] Host: So those -- that's kind of the essential, like, if you're going to fly, this is probably what you're going to need, you know, like the -- stuff like that, just in case some small thing were to come up, oh, I got a slight headache, boom, good to go. [00:20:45] Natacha Chough: Exactly. [00:20:45] Host: Okay, cool. What else besides Tylenol, I guess, that they would -- that they would need? [00:20:49] Natacha Chough: There's antibiotics onboard. If there's, you know, any sort of infection, but it's also, you know, kind of like what you have in your kitchen -- kitchen cabinet. Or, sorry, in your bathroom cabinet [laughing], so Pepto, you know, those types of things. [00:21:03] Host: Okay, cool! [00:21:04] Natacha Chough: But the quarantine process is actually pretty interesting. So I haven't been through that yet myself. I'm the prime doc for Jeanette, so I'll be in quarantine with her, but essentially we go from Star City, Russia, you know, where they train with the Russians, and the entire crew then flies down to Baikonur, Kazakhstan together. And then the prime crew and their prime docs will be in quarantine in Kazakhstan for about two weeks leading up to launch, and so everyday, you know, we take temperatures and do a quick physical exam and there's a Russian epidemiologist down there who's really strict about, you know, who he lets in to visit the crew and stuff, so no kids under 12, that type of thing. And anyone who does want to visit the crew has to, you know, have, you know, written evidence of like 3 days of like no fevers, and... [00:21:54] Host: Wow! [00:21:55] Natacha Chough: Yeah [laughing]. [00:21:56] Host: Alright, pretty -- I mean, it is strict for that reason. Right? They don't want to bring anything up there. So what's the -- have you been in the quarantine environment? [00:22:03] Natacha Chough: No, this will be -- I've visited it, but I haven't stayed there. [00:22:06] Host: Oh. So for Gen X launch, that will be the first time you're going to -- you're going to do it. Okay. [00:22:11] Natacha Chough: Yeah, so I've toured it. There's like a gym, you know, there's a place where they eat meals together and they have folks who are in quarantine with them, like cooks who stay there and cook for them, as well. [00:22:22] Host: Who have also gotten the check? [00:22:24] Natacha Chough: Exactly. Yep. [00:22:25] Host: So it's like a little place for them to live for how long? [00:22:29] Natacha Chough: About two weeks. [00:22:30] Host: Two weeks? Oh, wow. Okay, that's longer than I thought. Yeah, because, you know, you don't want anything to develop, how about that? [00:22:36] Natacha Chough: Right. And then, you know, obviously, flu vaccinations, depending on what time of year you're launching are important for everyone, going down range, to have as well. [00:22:44] Host: Absolutely. Alright, so then they're quarantined and then they go up to the International Space Station. You said they have very limited training when it comes to -- that, you know, they can do small things, but what sorts of things do you prepare for and prepare your crew members for for an emergency? [00:22:59] Natacha Chough: So, actually, they go through what we call megacode training, and so this would be like worst-case scenario, right, like if someone needs CPR. So, we work, again, with our -- our nurse trainers, typically they're nurses with ER backgrounds, and then the flight surgeon, as well, is watching the crew kind of go through this training after they've had a few sessions of hands-on, you know, training with us prior. So, and this is done in the -- the ISS mockup actually. And so we have an AAD [phonetic] on station, if needed. And so they run through, you know, a very modified, but basic algorithm that they would go through in that situation. [00:23:34] Host: Alright. So, okay, and -- and -- in this situation, are you on console helping them out? [00:23:40] Natacha Chough: Yes. So we would, you know, we always have a crew surgeon on console during normal working hours, and then we're on call the rest of the time when we're assigned to that mission. So, if we're not sitting in console on a regular shift, we would get called in for that. [00:23:56] Host: Alright. So no vacations then. You got to stick around in case someone gets pulled in, but that's good, right? Because then, you know, the crew members flying know that, alright, in case of an emergency, I know my -- my flight surgeon's going to be there. So whenever you're designing, you know, procedures, I guess, to do, do you, you know, practice knowing about microgravity? Like, okay, the AAD is going to have to -- we're going to have to do it this way because, you know, you can't just lay someone down, maybe strap them down or something like that? [00:24:24] Natacha Chough: Right. So we actually have a crew medical restraint system on station. And so, the crew know, you know, to put an incapacitated crew member there so that, you know, they don't float away. It's a lot different than it would be on earth. And so, yes, all our procedures are written to -- to account for the microgravity environment. [00:24:40] Host: Okay. Cool. Is there any -- any concerns from the flight surgeon area? Some unique things that flight surgeons in -- at NASA have to deal with that maybe other flight surgeons in the military don't have to worry about because of the microgravity environment? [00:24:55] Natacha Chough: So the biggest thing I'd say, like you mentioned, is, you know, medications, especially like liquids that don't separate from air, and so we're still trying to figure out, you know, how to -- how to work around that [inaudible] is that we do want to fly, but currently can't. [00:25:08] Host: Okay. So it's really just the limitations that... [00:25:10] Natacha Chough: Yeah, and so, you know, they're -- they're industry filters and stuff that -- that neonatal ICUs and that type of thing have worked with and could potentially be helpful. [00:25:20] Host: Cool. So, flight surgeons, I'm trying to think about like your -- your total duties, and they seem -- they seem pretty widespread, right? Like, so you're working with the crew before they launch, when they launch, in mission control, you even talked about some travel, right? You were flying out to Germany, have you been to Kazakhstan or Russia too? [00:25:39] Natacha Chough: Yeah. So, I'm one of the contractor docs, and so part of my job is to be in Star City, Russia where the crew train on Soyuz systems. And so I'm there two to three months out of the year. And that's actually really fun, I kind of like that, it's a very, like, family environment and the crew get together at night and we have family dinners and things like that. [00:26:01] Host: Oh, wow! So it's nice and tightknit. Like, family dinners where? Where they're staying? [00:26:05] Natacha Chough: Yeah, where they're staying. [00:26:06] Host: Okay. [00:26:07] Natacha Chough: Yep. And then -- so I've been to Russia for that and then, yes, I've been to Kazakhstan for a landing as -- as the air doc again on the NASA aircraft. [00:26:16] Host: Cool. NASA aircraft. So that -- was that the G3? [00:26:21] Natacha Chough: It was the G3, now it's G5. [00:26:23] Host: G5. Okay, so then that's the one they take from -- from where to where? [00:26:28] Natacha Chough: From Kazakhstan to Houston, and that's the direct return, what we call direct return within 24 hours of Soyuz landing. [00:26:33] Host: Oh, okay. So you're just watching the recently-landed astronauts and kind of taking care of them? Very cool. Did you take some of the helicopters out to the landing site and all that? [00:26:43] Natacha Chough: I have not actually . So I was on a Russian helicopter for Kate Rubins' launch, I was her deputy crew surgeon. And so for launch, the prime crew doc is, you know, near the launch site with the guest and family members, and then the backup doc, or the deputy doc, which was myself, is in a Russian surgeon rescue helicopter in the event that there's any sort of like launch abort scenario. We would be the ones to fly out to wherever the capsule would have aborted to. [00:27:13] Host: Oh, okay! First responders, boom, you're going. Alright. But you actually did -- you said you flew in the helicopter for Kate Rubins' landing? [00:27:20] Natacha Chough: So you -- they have the blades spinning, but you're staying on the tarmac until you get verification that they've reached orbit. [00:27:28] Host: Okay. [Laughing] Very cool. So what do you have to -- what do you have to study? What do you have to do to be a flight surgeon? Like what's your background? [00:27:35] Natacha Chough: Yeah, so my background is emergency medicine. And then to work at a NASA as a flight surgeon, you need to do an additional residency, and that's medical [inaudible] for specialty training [laughter]. And that residency has to be in aerospace medicine, not flight surgery, that's not a thing. So the expectation, essentially, is that you're a competent physician in whatever your chosen specialty is. [00:28:01] Host: Okay. [00:28:01] Natacha Chough: Before you pursue aerospace medicine because it's such a small and specialized field. I get a lot of questions actually from med students asking what they should specialize in if they want to become a NASA flight surgeon, and I always say, just choose what you love. Because if you love it, you're going to do it better, and that's what people are going to notice, and that's when doors are going to open to you. Because we've had neurologists, urologists, OB/GYNs, become flight surgeons and work here. So it's all about what you enjoy doing. [00:28:26] Host: Yeah, because they're really good, and you said yours was emergency medicine? [00:28:29] Natacha Chough: Yep. [00:28:29] Host: So what was -- what was that -- what were you doing before -- before NASA then in emergency medicine? [00:28:34] Natacha Chough: I actually went straight from emergency medicine residency to the UTMB Aerospace Medicine training program. [00:28:40] Host: Oh, okay. [00:28:41] Natacha Chough: So, yeah, I was just working, you know, 60 to 80 hours a week... [00:28:44] Host: Wow! Alright. [00:28:45] Natacha Chough: ....in the hospital before -- before doing the aerospace program. [00:28:49] Host: Alright. So then what was the aerospace program, how did that -- how do you translate emergency medicine into an aerospace environment? Like, what was different? [00:28:57] Natacha Chough: How did I transition it? I guess the emergency part applies to aerospace medicine in the event of, you know, like a mishap. So -- or planning for a mishap, but not necessarily hoping that that's what happens, right? So it's all about preparing for the worst and hoping for the best. So, emergency medicine, background-wise, can help you figure out what equipment you might need to pack or what equipment you can leave behind. What type of personnel and staffing and other resources you might need at different stages of like a rescue scenario. [00:29:31] Host: Yeah, because I guess you would have to operate assuming that you might have to do something maybe on a site, you know, so you're going to have to bring everything with you or something like that. [00:29:39] Natacha Chough: And you always have to think one step ahead, right? So like let's say I do this first step and it works, but then something else, you know, changes with the patient after that. Then what do I do? And so you have to kind of work out these mental algorithms instead, every possible scenario. [00:29:55] Host: And then from there, you kind of came into the world of NASA, I guess, through... [00:30:01] Natacha Chough: Yeah, so the UTMB Aerospace Medicine program is actually joint with NASA, and so we do some of our rotations here when we are in training, and so one of the ones is working -- is rotating through the flight medicine clinic. And so you're doing some of the astronaut physicals at that time. And then you've got other projects, operationally, that are given to you by different preceptors and mentors. One of my favorite ones was actually doing a one-month rotation with the BHP psychologists and psychiatrists. Just because it's not my specialty, and so I still find it like super interesting though to -- to work with them and see, you know, the types of issues that they deal with, and then interface with the -- the operational flight docs. [00:30:45] Host: Alright, very cool! And now -- now you're here at NASA, now you're a flight surgeon, what's -- it seems like, you know, like I said before, your duties are widespread and you're all over the place, but what's like a -- what's like a day-to-day sort of in the life of a flight surgeon? [00:31:01] Natacha Chough: Yeah, so, it's funny, people are always asking, like, what's a typical day for you? And I'm like, well, I -- I wouldn't say we have typical days, I would say we have typical weeks, but everyday can be a little bit different. So, we are in an engineering community, right? So we're the minority and a lot of times we're looked to as medical consultants, and with station being as complex of a program as it is, there are a lot of meetings with all these different disciplines to make sure that we're doing the right thing and maintaining the health and safety of the crew at the top. So, a lot of times, you know, I'll have a day that's nothing but meetings [laughing], with, you know, potentially questions for me about making, you know, just verifying that like what we're doing isn't medically contraindicated or unsafe in any way. You know, another day I might have my crew member doing a suited run in the MBL and so I'll be there observing that. You know, and another day I might have a couple of meetings in the morning and then in the afternoon my crew member will have some training, medical training, that I'll be attending and just making sure if they have any questions that I'm there. [00:32:05] Host: Okay. Yeah, it seems like your role is more -- is more operational, right? So if something's happening, like, boom, you're there. So, the Neutral Buoyancy Laboratory, that's a good one, right? That one's where the astronauts actually get suited up and practice doing a spacewalk in the pool. [00:32:19] Natacha Chough: Exactly. [00:32:19] Host: Right? So what's -- what's your role? Do you go behind the scenes and kind of check them out beforehand and afterwards? Or is it more you're just kind of standing by watching? [00:32:26] Natacha Chough: Yeah, so everyone who goes in the pool gets a dive physical beforehand. [00:32:29] Host: Dive physical, okay. [00:32:30] Natacha Chough: And then during the run, which is typically about 6 hours, I'll be on the loop just listening and making sure, you know, if there's any medical concerns, they can always request a private loop with the MBL medical director. But as their assigned flight surgeon, it's always good for us to be there, as well, just so we're aware of any issues. [00:32:48] Host: Yeah. Privacy is pretty important when it comes to this stuff, right? [00:32:51] Natacha Chough: Absolutely. [00:32:51] Host: Absolutely, yeah. So that -- your job is kind of -- is kind of like that, right? Whatever you do, you have to make sure that you are protecting the privacy of the astronaut's medical information. So, how does that work I guess in an environment where everyone's talking to each other? Especially in mission control. [00:33:10] Natacha Chough: Yeah. I guess it's not too different from the hospital environment. I think, you know, there are people who interface with us, for example, a biomedical engineer who have essentially [inaudible] of like, you know, a HIPAA, understanding of the HIPAA laws and medical privacy laws and privacy act. [00:33:27] Host: Oh, because they're hearing some of this information too? [00:33:29] Natacha Chough: Right. And, you know, the -- the ones who are involved in these types of conversations are involved because it's a need-to-know basis. And so that's essentially how we operate. [00:33:37] Host: Okay, cool. And you guys have private medical conferences with the astronauts too, right? Like every once in a while, you're checking in. So that's -- is it more of just that? It's just checking in, seeing how everything's going? [00:33:49] Natacha Chough: Yeah, so it's once a week, and it's for about 15 minutes, and it's a video conference direct to station with a crew member on a private loop, and, you know, it's all documented in -- in the chart, the medical chart, from that encounter, will go into the electronic medical record, and so we can always look back and see if there's something that we've been tracking over time, you know, how it's been progressing, but it is mostly a check-in, but, you know, every once in awhile, something will pop up. We know that there are slight immune system changes in space, so, people can get rashes or, you know, just feel stuffier, have allergy-type symptoms. And so a lot of times that's what we deal with. [00:34:31] Host: Okay. So it's -- how much of it is, you know, I guess you're recording, just checking in, and then, you know, sometimes you're going to have to deal with stuff like that, right? So how do you deal with it when you're down here in mission control, but your patient is up in space. [00:34:46] Natacha Chough: Yeah, so that's the art of telemedicine, right, is you can't see and touch and feel your patient yourself. And so we rely on their preflight medical training that we talked about. So they're taught to use, you know, how to use a stethoscope, how to take a blood pressure, how to measure heart rate, that type of thing, and then we have the magic of camera technology up there, so, you know, they can actually look in their crewmates ear and take a picture of what that eardrum looks like and send it down to us. Or they can just take a picture of a rash that's developed and send that down to us, and then, you know, during the private medical conference, we can ask all the other questions, we want to know, how long has it been there, and, you know, is it getting better or worse and what makes it better or worse, those types of things. [00:35:29] Host: Are the things that are normal for spaceflight, like, are there particular, you know, microgravity rashes or something like that that's just typical for being in a space environment or something like that? [00:35:41] Natacha Chough: Rashes can develop, yeah, so that's probably not uncommon, and it's because airflow on station is different than on earth, right? Like particles have weight to them here and there's constant airflow that moves things to different areas. So air doesn't -- heavier molecules don't dissipate or, you know, sink the same way on station. If you're staying motionless, the air particles around you are just going to heat up and you kind of have this like cloak of warmth, right? Or... [00:36:13] Host: Woah! [00:36:14] Natacha Chough: Another example would be if you unpacked something and it had, you know, particles of dust, the dust isn't going to like fall to the ground. [00:36:24] Host: Oh, it's going right up. Yeah. [00:36:25] Natacha Chough: So eye complaints can be a common thing that we hear about after something like that. So we've got protective equipment up there. If -- if we think something's going to be particularly hazardous for them to open or unpack, we recommend that they wear goggles and that type of thing. [00:36:39] Host: Wow! I would not have thought the -- like a heat shield, I guess, that's -- like happening because of the [inaudible]. That's interesting. [00:36:46] Natacha Chough: It's actually documented in Lost Moon, Jim Lovell's book about Apollo 13, when they had to turn a lot of the power systems off, it was really cold in there, but they found if they didn't move around as much, their body heat actually heated the air particles around them. [00:37:02] Host: Woah! [Laughter] That is wild to think about! So that's what I was talking about when I was asking, like, what are some of the microgravity things that are just different? That's perfect! That's exactly what I was -- I would have never thought, like, so -- so if you just stay still, you stay warm, because you're kind of moving, it's just a different air environment. How about that? So I guess are you the one in charge, though, if they are unpacking something, for example? Like, you say, hey, you definitely have to wear goggles for this or something like that? [00:37:31] Natacha Chough: It actually depends on who owns the hardware. But there's a lot of other system interfaces that I'm not privy to that I think come into play, and the biomedical engineer helps us out with that, as well. So they kind of -- biomedical engineers essentially are what -- we call them the nuts and bolts, they work with the nuts and bolts of medical hardware, right? So if the ultrasound machine breaks, they troubleshoot that. If the human breaks for whatever reason, like that's our job, we're the blood and guts. [00:37:58] Host: [Laughing] The blood and guts. [00:37:59] Natacha Chough: Yeah, but the rashes, going back to the rashes, so the -- the reason sometimes rashes develop is, so, back to our example of unpacking something that's new, maybe it's off gassing some sort of particles and those particles, if they're not circulating in the air the same way that they do on earth, can sort of linger in one space, maybe near your skin or something, and that sort of exposure with I guess not as efficient airflow as you would have on earth may make the skin react a little bit. But there's also, like I mentioned, some immune changes that happen and some rashes and allergy-type symptoms can be related to that, as well. [00:38:36] Host: Oh, because your immune system isn't operating as -- as much so you react, I guess, a little bit more? [00:38:42] Natacha Chough: Yeah, so we -- that's something we don't totally understand yet. And even on earth, the immune -- immunology is one of the least understood medical specialties out there. Things are always changing. [00:38:53] Host: See, I don't understand why I get a flu shot sometimes, and then a month later I get the flu! [Laughter] I don't understand. I should be completely protected! And I know there's, like, you know, changes in strands or something. So, anyway, but, yeah, no, a lot of different things to -- to think about, I guess, from -- from your end, especially just -- that's a totally different world. Are you -- are you measuring some of these things over -- over time? And then understanding trends? Like, are there certain trends that you've seen just from studying astronauts in space for so long? [00:39:26] Natacha Chough: So we've got a group of epidemiologists, and then folks on the research side who are studying particular, you know, body systems, for example, like you're in chemistry or whatnot, those are the ones who are typically measuring those types of trends. [00:39:40] Host: Okay. [00:39:40] Natacha Chough: Yeah. And so anything that goes into our electronic medical record, we can have the epidemiologists look at and they can, you know, identify trends and they can control for changes in like the CAT scan machine that was used from this mission to this mission, and control for age or gender or whatnot, and so it's a lot of number crunching and, you know, doing statistics and making sure that any trends or changes that we're seeing are statistically significant. [00:40:05] Host: Okay, yeah. Because I know, like, you know, just understanding, like just basic, when you go to space, this is something that happens sort of things. Right? So your immune system gets a little bit weaker, your -- your muscles and bones start to, you know, get a little bit weaker and disappear so you have to build it back up and do this exercise all the time. Just medical things that you have to think about, you know, the human body, how it reacts to space. And these are things, these are lessons that we can take to missions beyond low-earth orbit too, right, to -- to station, our past station to, you know, the moon, deep space, Mars, all of that stuff. So how is the role of a flight surgeon going to change as we -- as the communication starts to get a little bit, you know, longer. Because when we go out to Mars, you're talking about when earth and Mars are at their farthest point away from each other, that's like a 40-something minute round trip for communication. [00:41:01] Natacha Chough: Yeah. Yeah, so, and the question is, right, like, do you then have a requirement to have a doctor onboard? And not only that, but what if the doctor is the one who is sick and becomes the patient, then what? Right? Because when you fly in an aircraft, you've got a pilot and a co-pilot, but if you've only got one doctor, I don't know, like, is it enough for someone else to, you know, be trained as a mid-level provider, like a physician assistant or a nurse practitioner or is it enough to have just in time, like on-orbit, you know, refresher training videos for a non-physician to be able to do a medical procedure? Do we need, you know, minimally-invasive surgery type capabilities on these spacecrafts? And those are all questions that, like I said, people way smarter than me are -- are looking into and challenges that we still need to address. [00:41:51] Host: Wow. Yeah, because there's -- there's a lot of different considerations. We just did a podcast pretty recently with Orion, and they were talking about just, like, for example, oxygen or something, right, like oxygen is super important to have on the spacecraft, but you can only put so many oxygen generators on the spacecraft before it becomes a little bit, okay, let's -- let's calm down. You know, because you have backups, but you can't just make -- keep making backups until you're perfectly fine. So the same with the physician's, right? You can't just have, like, an army of doctors going to space because, you know, it's just you need those other things, right, you can have a doctor, but then you need -- if you're doing Mars exploration, maybe a geologist, maybe an engineer, maybe a pilot, you know, you need all of the above, nice like diverse group of -- of astronauts who can do -- do it all in the -- in one mission. [00:42:40] Natacha Chough: Yeah, and I think also the -- the crew psychology is going to change a little bit. [00:42:45] Host: Oh yeah. [00:42:46] Natacha Chough: And so, you know, people have talked about, what's the ideal crew make up? Should they all be all one gender, should they have an even number versus an odd number? Because if you have an even number and you have a disagreement and you vote on something, what do you do if you have a tie? But if you have an odd number of crew members and there's one person who's the tiebreaker, are they then sort of, you know, like labeled as... [00:43:08] Host: Yeah. [00:43:09] Natacha Chough: You know? [00:43:09] Host: She's inside [inaudible] that guy or something. [00:43:11] Natacha Chough: And then there's questions about what kind of -- what degree of assertiveness or leadership do you want your commander versus someone who fosters more equality in community in a multi month, like, transit phase from earth to Mars, where there's not a lot going on, so do you really want somebody who's like super dominant on you all the time about something... [00:43:31] Host: Yeah. [00:43:31] Natacha Chough: ...when there's not a lot of operational things happening. [00:43:35] Host: Yeah. [00:43:35] Natacha Chough: Yeah, so a lot of -- a lot of factors there are going to be in play, but I think crew psychology and wellness is going to be huge. [00:43:43] Host: Oh yeah. I would assume that whatever crew they choose to do these deep space missions, they're going to be, you know, be able to do it all in a sense. They'll be super qualified people that have multiple disciplines, and when with the most recent astronaut class, that's reflected there too. You've got doctors with flight time, you've got Navy Seals slash doctor, you have, to know, an engineer in four different disciplines, so, you know, you got all of these people that can -- that can do it all. It's pretty cool. [Laughing] I guess from a flight surgeon perspective, you'd probably go more towards the -- the redundancy in doctor ability, like a doctor and then someone trained mid-level with the doctor, physician? [00:44:26] Natacha Chough: Potentially. Yeah, I mean, I guess I haven't really thought about it too much. I was just kind of like throwing out ideas, but [laughter], I mean, it's always good, you know, to have backups and potentially backups to your backup, so. [00:44:38] Host: So how about whenever, I mean, you know, we're going -- we're going out, way out into space, but I'm going to pull back for just a second. Like, your first -- your first time going out over to overseas, to support like a crew thing. I'm only asking -- I'm asking this selfishly because I'm about to go over to Kazakhstan myself. So what was -- what was that like, that experience of -- of, you know, working with the crew before a launch or after a landing or your first time? [00:45:05] Natacha Chough: So it actually felt very natural to me, and I think part of the reason is because I was a Peace Corp volunteer like before I went to medical school, and I was -- I lived in that region of the world. So I was doing service in Turkmenistan, and so to be in Kazakhstan was almost like coming home. So I felt very comfortable and part of that experience really turned me onto the International Space Station program because of the international cooperation part of it. So going over there was actually really fun for me, I really enjoyed it. And as to like the actual pre-launch experience, so as the deputy crew surgeon, for my first mission, your job is to take care of the family and launch guests that are invited. And so, you know, some folks aren't frequent international travelers, and Kazakhstan is fairly remote, so, you know, if you've got medical conditions, you know, I was trying to remind people to bring all their prescription meds that they're going to need, because we don't always necessarily have what they're going to need. We do carry a small medical pack with us with some like sleep meds and, you know, allergy meds, that type of thing, in case it's needed. [00:46:13] And then really it's just getting to know them, getting to make sure that your prime surgeon who's locked in quarantine has everything they need. If not, you know, we can arrange to -- to have extra supplies brought into them, you know, medically, if -- if they need something. And then the day of launch, depending on what time you launch, this may happen earlier or later, but I got up super early with our, you always have a nurse with you when you're going out into the field, and so we had the search and rescue forces pick us up in a van, and we went to the remote airport where their helicopter was staged to stay on the helicopter and wait for launch, and then once we got word that the crew had reached orbit, then the helicopter blade stops spinning and then we just go back to the hotel. So I -- on an ideal day, on launch, you're actually not doing too much, because things are working as they should. [00:47:08] Host: Right. Because your job is to be there, like, the helicopter blade spinning is the perfect analogy to, you know, if something goes wrong, you're getting in the helicopter. Right? That is your job. Otherwise, the blade stops spinning. So, that's exactly, cool. Wow, alright, a lot of -- a lot of cool stuff to do as a flight surgeon. Is there anything I missed about flight surgery, because a lot of this is very foreign to me because I, you know, medical stuff goes like right over my head [laughing], but I try -- I try to do my best to kind of summarize everything into something that's, you know, that we can tell out to the world and that makes a lot of sense and kind of encapsulates the story of astronaut health. [00:47:50] Natacha Chough: Oh, so there was one thing I was going to say. So, and this is kind of like a misconception that I think is important to clear up for folks out there who are interested in becoming a flight surgeon or who are in medical school. [00:48:00] Host: Yeah. [00:48:01] Natacha Chough: So, some flight surgeons have gone on to become astronauts, and subsequently flown in space, but they're in the minority. So being a flight surgeon is not a shortcut to becoming an astronaut, I'm sorry if I'm crushing any dreams out there, but we get to do a lot of what an astronaut does, except fly in space. So we're with them for a lot of the training they do, and, you know, while space is, no doubt, the best part of being an astronaut, it's a pretty small percentage of their career, so, like, I don't feel too bad about my job, I actually love my job, and it's -- there's another doc in our group who refers to it as being like, taking care of Lewis and Clark. And so I think that's totally appropriate and it's super rewarding. We are one of the first faces they see, you know, on landing. So if you see the -- the PAO shots of the crew getting pulled out of the Soyuz, we're like the, you know, the other person in the blue flight suit in the corner [laughing], making sure they're okay along with our -- we've got great Russian field medical nurses that help us out with taking vitals and all of that, so. [00:48:58] Host: That's right. You're there for every step of the way, except on the International Space Station. [00:49:02] Natacha Chough: That is okay. [00:49:03] Host: Yeah, that's -- oh, really, you wouldn't want to -- you wouldn't want to fly? [00:49:07] Natacha Chough: Oh, no, I just mean, you know, this job is so rewarding for me as is that I'm happy as a clam. [00:49:13] Host: Hey, yeah, you can't complain, because you're doing -- you're doing some really, really cool stuff. That's really awesome. Yeah, well if you -- if you do, you know, want to be a flight surgeon slash astronaut, there -- is it -- is it Kell Lindgren [phonetic]? [00:49:26] Natacha Chough: Kjell. [00:49:26] Host: Kjell Lindgren, yeah, Kjell Lindgren was a flight surgeon turned astronaut, right? [00:49:31] Natacha Chough: And Mike Beret, Tom Marshburn, and then Serena Aunon-Chancellor [phonetic] next year. [00:49:36] Host: What? Oh, all of them? [00:49:37] Natacha Chough: They were all previously flight surgeons. [00:49:39] Host: Ahhh, so you say it's low, but there's quite a few [laughter], there's quite a few! And, you know, definitely a medical doctor, I think, would be up there for someone who's essential on a deep space mission. I definitely think, you know, for missions beyond, they're going to be -- they're going to be up there. Because the human body is like -- it's one of the things we're focusing on when we're doing studies on the International Space Station, right? Like, studies on the human body, but then it's going to be a huge factor for missions beyond, because there's different things you have to worry about. [00:50:09] Natacha Chough: And we're the most annoying variable, I would say, right? Like, to -- to an engineer's who's focused on, you know, the spacecraft and things being like within binary ranges, we have the most variables within our physiologic system to -- to have the potential to drive folks crazy. So sometimes we'll get questions, you know, like, well, what's, you know, how low can this temperature be, or whatever, like, well, it depends. It depends on, you know, [laughing] all these different factors. And so I know that's -- that's hard to hear sometimes. So, you know, we have to -- to bound the question appropriately and then, you know, start from a place that's, you know, medically, ethically, you know, safe for the crew, and then that's your starting point to -- to work from there. [00:50:51] Host: Yeah. Yeah, and it's just -- it's got to be so cool just working with an astronaut throughout the whole thing. Have you ever done the 0 gravity flight? [00:50:58] Natacha Chough: Yes! Yep, that's part of our training as well. [00:51:00] Host: Alright! So that's -- so that's pretty close to space, right? [00:51:03] Natacha Chough: Yeah. [00:51:03] Host: You kind of feel the microgravity. [00:51:06] Natacha Chough: It's for 30 -- about 30 seconds at a time. Yeah, it's pretty much exactly how I imagined it like in my dreams as a kid. It was actually super fun, and it's -- it felt like Christmas [laughing]. That's like the best way I can describe it. [00:51:18] Host: Wow. Did you -- were you there as a flight surgeon like with an astronaut, or were you there for something else? [00:51:24] Natacha Chough: I was there as like an aerospace medicine resident in training. It was sort of just like an exposure flight for me. [00:51:31] Host: Yeah [laughing]. [00:51:31] Natacha Chough: It was super fun! [00:51:33] Host: Alright. Something definitely cool to get exposed to, right? That's like a once-in-a-lifetime kind of thing. That's pretty cool. [00:51:40] Natacha Chough: I'll take that over the, you know, losing brain cells in the hypoxia chamber [laughter]. [00:51:43] Host: Yeah! Unfortunately, that's something you've done multiple times. Multiple 0 gravity flights would be pretty cool. Alright. Alright, well, Natacha, thanks so much for coming on the show. I think this was a nice -- nice overview of what a flight surgeon does and how it helps in, you know, every step of the way for Lewis and Clark, I love that analogy, that's perfect. So, thanks for coming on the show and talking about what a flight surgeon does. [00:52:03] Natacha Chough: Thanks for having me! [00:52:04] Host: Very cool. [00:52:05] [ Music ] [00:52:14] [ Music & Radio Transmissions ] Host: Hey! Thanks for sticking around. So today we talked with Dr. Natacha Chough about her role as a flight surgeon and what that has to do with astronaut health. If you want to know what's going on in the role of human research and how that applies to spaceflight, NASA,gov/hrp is a great resource for all of that. Everything human research and how that applies to spaceflight. If you go to NASA.gov/iss, you can figure out all the stuff going on on the International Space Station, and a lot of that has to do with some of the human research we're doing, as we talked about it in this episode. Otherwise, on social media, you can follow us Facebook, Twitter, Instagram, follow the International Space Station accounts, they're verified and, you know, we got a lot of followers, so you can find us pretty easily. But just use the hashtag, AskNASA, on any one of those platforms, if you want to ask a question about the show, and actually that's where I found the recommendation for this show, is actually on Twitter. [00:53:19] So, I'm paying attention to all of that, just make sure to mention it's for Houston, we have a podcast, and then -- and then we'll go from there! So, the credits for today go to John [inaudible] and Alex [inaudible]. Thanks again to Dr. Natacha Chough for coming on the show this week. This podcast was recorded on November 15th. We'll be back next week!