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Sample records for breathing cardiovascular variability

  1. Cardiovascular Biomarkers In Exhaled Breath

    PubMed Central

    Cikach, Frank S.; Dweik, Raed A.

    2014-01-01

    With each breath we exhale, thousands of molecules are expelled in our breath giving individuals a “breath-print” that can tell a lot about them and their state of health. Breath analysis is rapidly evolving as the new frontier in medical testing. The end of the 20th century and the beginning of the 21st century have arguably witnessed a revolution in our understanding of the constituents of exhaled breath and the development of the field of breath analysis and testing. Thanks to major breakthroughs in new technologies (infrared, electrochemical, chemiluminescence, and others) and the availability of mass spectrometers, the field of breath analysis has made considerable advances in the 21st century. Several methods are now in clinical use or nearly ready to enter that arena. Breath analysis has the potential to offer relatively inexpensive, rapid, noninvasive methods for detecting and/or monitoring a variety of diseases. Breath analysis also has applications in fields beyond medicine, including environmental monitoring, security and others. This review will focus on exhaled breath as a potential source of biomarkers for medical applications with specific attention to applications (and potential applications) in cardiovascular disease. PMID:22824108

  2. Slow breathing and cardiovascular disease.

    PubMed

    Chaddha, Ashish

    2015-01-01

    Cardiovascular disease is the leading cause of death for both men and women worldwide. Much emphasis has been placed on the primary and secondary prevention of cardiovascular disease. While depression and anxiety increase the risk of developing cardiovascular disease, cardiovascular disease also increases the risk of developing anxiety and depression. Thus, promoting optimal mental health may be important for both primary and secondary prevention of cardiovascular disease. Like lowering blood pressure, lipids, and body weight, lowering anger and hostility and improving depression and anxiety may also be an important intervention in preventive cardiology. As we strive to further improve cardiovascular outcomes, the next bridge to cross may be one of offering patients nonpharmacologic means for combating daily mental stress and promoting mental health, such as yoga and pranayama. Indeed, the best preventive cardiovascular medicine may be a blend of both Western and Eastern medicine. PMID:26170595

  3. Slow breathing and cardiovascular disease

    PubMed Central

    Chaddha, Ashish

    2015-01-01

    Cardiovascular disease is the leading cause of death for both men and women worldwide. Much emphasis has been placed on the primary and secondary prevention of cardiovascular disease. While depression and anxiety increase the risk of developing cardiovascular disease, cardiovascular disease also increases the risk of developing anxiety and depression. Thus, promoting optimal mental health may be important for both primary and secondary prevention of cardiovascular disease. Like lowering blood pressure, lipids, and body weight, lowering anger and hostility and improving depression and anxiety may also be an important intervention in preventive cardiology. As we strive to further improve cardiovascular outcomes, the next bridge to cross may be one of offering patients nonpharmacologic means for combating daily mental stress and promoting mental health, such as yoga and pranayama. Indeed, the best preventive cardiovascular medicine may be a blend of both Western and Eastern medicine. PMID:26170595

  4. Controlled breathing protocols probe human autonomic cardiovascular rhythms

    NASA Technical Reports Server (NTRS)

    Cooke, W. H.; Cox, J. F.; Diedrich, A. M.; Taylor, J. A.; Beightol, L. A.; Ames, J. E. 4th; Hoag, J. B.; Seidel, H.; Eckberg, D. L.

    1998-01-01

    The purpose of this study was to determine how breathing protocols requiring varying degrees of control affect cardiovascular dynamics. We measured inspiratory volume, end-tidal CO2, R-R interval, and arterial pressure spectral power in 10 volunteers who followed the following 5 breathing protocols: 1) uncontrolled breathing for 5 min; 2) stepwise frequency breathing (at 0.3, 0.25, 0.2, 0.15, 0.1, and 0.05 Hz for 2 min each); 3) stepwise frequency breathing as above, but with prescribed tidal volumes; 4) random-frequency breathing (approximately 0.5-0.05 Hz) for 6 min; and 5) fixed-frequency breathing (0.25 Hz) for 5 min. During stepwise breathing, R-R interval and arterial pressure spectral power increased as breathing frequency decreased. Control of inspired volume reduced R-R interval spectral power during 0.1 Hz breathing (P < 0.05). Stepwise and random-breathing protocols yielded comparable coherence and transfer functions between respiration and R-R intervals and systolic pressure and R-R intervals. Random- and fixed-frequency breathing reduced end-tidal CO2 modestly (P < 0.05). Our data suggest that stringent tidal volume control attenuates low-frequency R-R interval oscillations and that fixed- and random-rate breathing may decrease CO2 chemoreceptor stimulation. We conclude that autonomic rhythms measured during different breathing protocols have much in common but that a stepwise protocol without stringent control of inspired volume may allow for the most efficient assessment of short-term respiratory-mediated autonomic oscillations.

  5. A computational physiology approach to personalized treatment models: the beneficial effects of slow breathing on the human cardiovascular system.

    PubMed

    Fonoberova, Maria; Mezić, Igor; Buckman, Jennifer F; Fonoberov, Vladimir A; Mezić, Adriana; Vaschillo, Evgeny G; Mun, Eun-Young; Vaschillo, Bronya; Bates, Marsha E

    2014-10-01

    Heart rate variability biofeedback intervention involves slow breathing at a rate of ∼6 breaths/min (resonance breathing) to maximize respiratory and baroreflex effects on heart period oscillations. This intervention has wide-ranging clinical benefits and is gaining empirical support as an adjunct therapy for biobehavioral disorders, including asthma and depression. Yet, little is known about the system-level cardiovascular changes that occur during resonance breathing or the extent to which individuals differ in cardiovascular benefit. This study used a computational physiology approach to dynamically model the human cardiovascular system at rest and during resonance breathing. Noninvasive measurements of heart period, beat-to-beat systolic and diastolic blood pressure, and respiration period were obtained from 24 healthy young men and women. A model with respiration as input was parameterized to better understand how the cardiovascular processes that control variability in heart period and blood pressure change from rest to resonance breathing. The cost function used in model calibration corresponded to the difference between the experimental data and model outputs. A good match was observed between the data and model outputs (heart period, blood pressure, and corresponding power spectral densities). Significant improvements in several modeled cardiovascular functions (e.g., blood flow to internal organs, sensitivity of the sympathetic component of the baroreflex, ventricular elastance) were observed during resonance breathing. Individual differences in the magnitude and nature of these dynamic responses suggest that computational physiology may be clinically useful for tailoring heart rate variability biofeedback interventions for the needs of individual patients.

  6. Variability and cardiovascular homeostasis.

    PubMed

    Hughson, R L; Gharib, C

    1995-01-01

    The inability to maintain the upright posture due to a failure in the arterial blood pressure regulatory mechanisms on return from space travel or after a period of head down tilt bed rest (HDBR) is the ultimate sign of cardiovascular deconditioning. Yet, the final response of syncope is potentially heralded by a series of precursor events that can be quantified and analyzed in new, more insightful ways to attempt to understand the integrative nature of autonomic control of the cardiovascular system.

  7. Impact of breath holding on cardiovascular respiratory and cerebrovascular health.

    PubMed

    Dujic, Zeljko; Breskovic, Toni

    2012-06-01

    Human underwater breath-hold diving is a fascinating example of applied environmental physiology. In combination with swimming, it is one of the most popular forms of summer outdoor physical activities. It is performed by a variety of individuals ranging from elite breath-hold divers, underwater hockey and rugby players, synchronized and sprint swimmers, spear fishermen, sponge harvesters and up to recreational swimmers. Very few data currently exist concerning the influence of regular breath holding on possible health risks such as cerebrovascular, cardiovascular and respiratory diseases. A literature search of the PubMed electronic search engine using keywords 'breath-hold diving' and 'apnoea diving' was performed. This review focuses on recent advances in knowledge regarding possibly harmful physiological changes and/or potential health risks associated with breath-hold diving. Available evidence indicates that deep breath-hold dives can be very dangerous and can cause serious acute health problems such a collapse of the lungs, barotrauma at descent and ascent, pulmonary oedema and alveolar haemorrhage, cardiac arrest, blackouts, nitrogen narcosis, decompression sickness and death. Moreover, even shallow apnoea dives, which are far more frequent, can present a significant health risk. The state of affairs is disturbing as athletes, as well as recreational individuals, practice voluntary apnoea on a regular basis. Long-term health risks of frequent maximal breath holds are at present unknown, but should be addressed in future research. Clearly, further studies are needed to better understand the mechanisms related to the possible development or worsening of different clinical disorders in recreational or competitive breath holding and to determine the potential changes in training/competition regimens in order to prevent these adverse events.

  8. The importance of sleep-disordered breathing in cardiovascular disease.

    PubMed

    Linz, Dominik; Woehrle, Holger; Bitter, Thomas; Fox, Henrik; Cowie, Martin R; Böhm, Michael; Oldenburg, Olaf

    2015-09-01

    Obstructive sleep apnoea and central sleep apnoea/Cheyne-Stokes respiration are collectively referred to as sleep-disordered breathing (SDB). Rapidly accumulating evidence suggests that both forms of SDB, and often a combination of both, are highly prevalent in patients with a wide variety of cardiovascular diseases, including hypertension, heart failure, arrhythmias, coronary artery disease, acute coronary syndrome and stroke. The presence of SDB in these patients is independently associated with worse cardiac function and exercise tolerance, recurrent arrhythmias, infarct expansion, decreased quality of life and increased mortality. Recent data suggest positive effects of positive airway pressure (PAP) therapy on quality of life and cardiovascular function. In addition, ongoing clinical trials may soon provide first definitive data on PAP therapy of SDB on hard outcomes such as mortality. This review presents current data highlighting links between SDB and a variety of cardiovascular conditions, the importance of recognising and diagnosing SDB in patients with cardiovascular disease, and the effects of effective SDB treatment on cardiovascular endpoints.

  9. Cardiovascular Disease and Sleep-Disordered Breathing in Acromegaly.

    PubMed

    Powlson, Andrew S; Gurnell, Mark

    2016-01-01

    Treatment goals in acromegaly include symptom relief, tumour control and reversal of the excess morbidity and mortality associated with the disorder. Cardiovascular complications include concentric biventricular hypertrophy and cardiomyopathy, hypertension, valvular heart disease and arrhythmias, while metabolic disturbance (insulin resistance/diabetes mellitus, dyslipidaemia) further increases the risk of cardiovascular and cerebrovascular events. Sleep-disordered breathing (in the form of sleep apnoea) is also common in patients with acromegaly and may exacerbate cardiovascular dysfunction, in addition to contributing to impaired quality of life. Accordingly, and in keeping with evidence that cardiorespiratory complications in acromegaly are not automatically reversed/ameliorated simply through the attainment of 'safe' growth hormone and insulin-like growth factor 1 levels, recent guidelines have emphasised the need not only to achieve stringent biochemical control, but also to identify and independently treat these comorbidities. It is important, therefore, that patients with acromegaly are systematically screened at diagnosis, and periodically thereafter, for the common cardiovascular and respiratory manifestations and that biochemical targets do not become the only treatment goal.

  10. Cardiovascular Disease and Sleep-Disordered Breathing in Acromegaly.

    PubMed

    Powlson, Andrew S; Gurnell, Mark

    2016-01-01

    Treatment goals in acromegaly include symptom relief, tumour control and reversal of the excess morbidity and mortality associated with the disorder. Cardiovascular complications include concentric biventricular hypertrophy and cardiomyopathy, hypertension, valvular heart disease and arrhythmias, while metabolic disturbance (insulin resistance/diabetes mellitus, dyslipidaemia) further increases the risk of cardiovascular and cerebrovascular events. Sleep-disordered breathing (in the form of sleep apnoea) is also common in patients with acromegaly and may exacerbate cardiovascular dysfunction, in addition to contributing to impaired quality of life. Accordingly, and in keeping with evidence that cardiorespiratory complications in acromegaly are not automatically reversed/ameliorated simply through the attainment of 'safe' growth hormone and insulin-like growth factor 1 levels, recent guidelines have emphasised the need not only to achieve stringent biochemical control, but also to identify and independently treat these comorbidities. It is important, therefore, that patients with acromegaly are systematically screened at diagnosis, and periodically thereafter, for the common cardiovascular and respiratory manifestations and that biochemical targets do not become the only treatment goal. PMID:26227953

  11. Essential Hypertension: Cardiovascular Response to Breath Hold Combined with Exercise.

    PubMed

    Hoffmann, U; Urban, P; Koschate, J; Drescher, U; Pfister, R; Michels, G

    2015-07-01

    Essential hypertension (EH) is a widespread disease and might be prevalent in apnea divers and master athletes. Little is known about the influence of EH and the antihypertensive drugs (AHD) on cardiovascular reactions to combined breath hold (BH) and exercise. In this pilot study, healthy divers (HCON) were compared with treated hypertensive divers with regard to heart rate (HR) and mean blood-pressure (MAP) responses to BH, exercise and the combination of both. Ten subjects with EH and ten healthy divers were tested. 3 different 20 s stimuli were applied: BH combined with 30 W or 150 W and 150 W without BH. The time-charts during the stress intervals and during recovery were compared. Subjects treated with an angiotensin-converting enzyme (ACE) inhibitor showed higher changes for MAP values if breath hold was performed. HR responses were obviously changed if a β-blocker was part of the medication. One subject showed extreme MAP responses to all stimuli and conspicuous HR if BH was involved. The modulation of HR-/MAP-response in EH subjects depends on the mechanisms of antihypertensive agents. The combination of an ACE inhibitor and a β-blocker may give the best protection. It is recommended to include short apnea tests in the fitness-to-dive examination to individually predict potential endangerment. PMID:25875316

  12. Variability of the breathing pattern before and after extubation.

    PubMed

    Krieger, B P; Chediak, A; Gazeroglu, H B; Bizousky, F P; Feinerman, D

    1988-04-01

    A stable breathing pattern during unassisted ventilation through an endotracheal tube (ETT) prior to extubation is an important factor in determining whether a patient can be successfully extubated. Proper interpretation of changes in the breathing pattern requires knowledge of the normal variability of the breathing pattern in critically ill, intubated patients. To establish these guidelines, 50 spontaneously breathing patients who were being weaned from mechanical ventilation were monitored with respiratory inductive plethysmography for one hour immediately prior to and following successful extubation. Immediately after extubation, respiratory rate (f), tidal volume (VT), minute ventilation, and mean inspiratory flow increased slightly. By 30 minutes postextubation, these parameters were similar to preextubation values. There was no significant change in variability of f or VT. Although the breathing pattern of these relatively stable, intensive care patients differed from values of normal ambulatory subjects, values were similar in the preextubation and postextubation periods.

  13. Redundant and synergistic information transfer in cardiovascular and cardiorespiratory variability.

    PubMed

    Faes, Luca; Porta, Alberto; Nollo, Giandomenico

    2015-08-01

    In the framework of information dynamics, new tools are emerging which allow one to quantify how the information provided by two source processes about a target process results from the contribution of each source and from the interaction between the sources. We present the first implementation of these tools in the assessment of short-term cardiovascular and cardiorespiratory variability, by introducing two strategies for the decomposition of the information transferred to heart period (HP) variability from systolic arterial pressure (SAP) and respiration flow (RF) variability. Several measures based on the notion of transfer entropy (TE) are defined to quantify joint, individual and redundant/synergistic information transfer, and are then estimated from the series of HP, SAP and RF obtained from healthy subjects during head-up tilt and paced breathing protocols. Our results show that the proposed information decomposition methods provide an enhanced view on cardiovascular and cardiorespiratory regulation.

  14. Beat to beat variability in cardiovascular variables: noise or music?

    NASA Technical Reports Server (NTRS)

    Appel, M. L.; Berger, R. D.; Saul, J. P.; Smith, J. M.; Cohen, R. J.

    1989-01-01

    Cardiovascular variables such as heart rate, arterial blood pressure, stroke volume and the shape of electrocardiographic complexes all fluctuate on a beat to beat basis. These fluctuations have traditionally been ignored or, at best, treated as noise to be averaged out. The variability in cardiovascular signals reflects the homeodynamic interplay between perturbations to cardiovascular function and the dynamic response of the cardiovascular regulatory systems. Modern signal processing techniques provide a means of analyzing beat to beat fluctuations in cardiovascular signals, so as to permit a quantitative, noninvasive or minimally invasive method of assessing closed loop hemodynamic regulation and cardiac electrical stability. This method promises to provide a new approach to the clinical diagnosis and management of alterations in cardiovascular regulation and stability.

  15. Heart Rate Variability Dynamics for the Prognosis of Cardiovascular Risk

    PubMed Central

    Ramirez-Villegas, Juan F.; Lam-Espinosa, Eric; Ramirez-Moreno, David F.; Calvo-Echeverry, Paulo C.; Agredo-Rodriguez, Wilfredo

    2011-01-01

    Statistical, spectral, multi-resolution and non-linear methods were applied to heart rate variability (HRV) series linked with classification schemes for the prognosis of cardiovascular risk. A total of 90 HRV records were analyzed: 45 from healthy subjects and 45 from cardiovascular risk patients. A total of 52 features from all the analysis methods were evaluated using standard two-sample Kolmogorov-Smirnov test (KS-test). The results of the statistical procedure provided input to multi-layer perceptron (MLP) neural networks, radial basis function (RBF) neural networks and support vector machines (SVM) for data classification. These schemes showed high performances with both training and test sets and many combinations of features (with a maximum accuracy of 96.67%). Additionally, there was a strong consideration for breathing frequency as a relevant feature in the HRV analysis. PMID:21386966

  16. Infant breathing rate counter based on variable resistor for pneumonia

    NASA Astrophysics Data System (ADS)

    Sakti, Novi Angga; Hardiyanto, Ardy Dwi; La Febry Andira R., C.; Camelya, Kesa; Widiyanti, Prihartini

    2016-03-01

    Pneumonia is one of the leading causes of death in new born baby in Indonesia. According to WHO in 2002, breathing rate is very important index to be the symptom of pneumonia. In the Community Health Center, the nurses count with a stopwatch for exactly one minute. Miscalculation in Community Health Center occurs because of long time concentration and focus on two object at once. This calculation errors can cause the baby who should be admitted to the hospital only be attended at home. Therefore, an accurate breathing rate counter at Community Health Center level is necessary. In this work, resistance change of variable resistor is made to be breathing rate counter. Resistance change in voltage divider can produce voltage change. If the variable resistance moves periodically, the voltage will change periodically too. The voltage change counted by software in the microcontroller. For the every mm shift at the variable resistor produce average 0.96 voltage change. The software can count the number of wave generated by shifting resistor.

  17. Heart rate variability and stroke volume variability to detect central hypovolemia during spontaneous breathing and supported ventilation in young, healthy volunteers.

    PubMed

    Elstad, Maja; Walløe, Lars

    2015-04-01

    Cardiovascular oscillations exist in many different variables and may give important diagnostic and prognostic information in patients. Variability in cardiac stroke volume (SVV) is used in clinical practice for diagnosis of hypovolemia, but currently is limited to patients on mechanical ventilation. We investigated if SVV and heart rate variability (HRV) could detect central hypovolemia in spontaneously breathing humans: We also compared cardiovascular variability during spontaneous breathing with supported mechanical ventilation.Ten subjects underwent simulated central hypovolemia by lower body negative pressure (LBNP) with >10% reduction of cardiac stroke volume. The subjects breathed spontaneously and with supported mechanical ventilation. Heart rate, respiratory frequency and mean arterial blood pressure were measured. Stroke volume (SV) was estimated by ModelFlow (Finometer). Respiratory SVV was calculated by: 1) SVV% = (SVmax - SVmin)/SVmean during one respiratory cycle, 2) SVIntegral from the power spectra (Fourier transform) at 0.15-0.4 Hz and 3) SVV_norm = (√SVIntegral)/SVmean. HRV was calculated by the same methods.During spontaneous breathing two measures of SVV and all three measures of HRV were reduced during hypovolemia compared to baseline. During spontaneous breathing SVIntegral and HRV% were best to detect hypovolemia (area under receiver operating curve 0.81). HRV% ≤ 11% and SVIntegral ≤ 12 ml(2) differentiated between hypovolemia and baseline during spontaneous breathing.During supported mechanical ventilation, none of the three measures of SVV changed and two of the HRV measures were reduced during hypovolemia. Neither measures of SVV nor HRV were classified as a good detector of hypovolemia.We conclude that HRV% and SVIntegral detect hypovolemia during spontaneous breathing and both are candidates for further clinical testing. PMID:25799094

  18. Tai Chi Chuan modulates heart rate variability during abdominal breathing in elderly adults.

    PubMed

    Wei, Gao-Xia; Li, You-Fa; Yue, Xiao-Lin; Ma, Xiao; Chang, Yu-Kai; Yi, Long-Yan; Li, Jing-Cheng; Zuo, Xi-Nian

    2016-03-01

    Tai Chi Chuan (TCC) practice is currently intentionally applied in clinical populations, especially those with cardiovascular diseases because of its potential benefits on the autonomic nervous system. The long-term effect of TCC practice on heart rate variability (HRV) remains largely unknown. In this study, we recruited 23 TCC practitioners whose experience averaged approximately 21 years and 19 controls matched by age, sex and education to examine the effect of TCC practice on the autonomic nervous system during a resting state and during an abdominal breathing state. HRV was measured by traditional electrocardiogram (ECG) recording. The results showed that the low frequency, total power frequency, and normalized low frequency components and the low-frequency/high-frequency ratio were significantly higher, whereas the normalized high frequency was significantly lower in the TCC practitioners relative to controls during the abdominal breathing state. However, we did not detect any significant difference in the HRV measures during the resting state between the two groups. Additionally, TCC experience did not correlate with HRV components either in the abdominal state or the resting state in the TCC group. Considering all of these findings, we suggest that TCC improves vagal activity and the balance between sympathetic and parasympathetic activity during the relaxation state. This study also provides direct physiological evidence for the role of TCC practice in relaxation.

  19. Anatomic and Pathologic Variability During Radiotherapy for a Hybrid Active Breath-Hold Gating Technique

    SciTech Connect

    Glide-Hurst, Carri K.; Gopan, Ellen; Hugo, Geoffrey D.

    2010-07-01

    Purpose: To evaluate intra- and interfraction variability of tumor and lung volume and position using a hybrid active breath-hold gating technique. Methods and Materials: A total of 159 repeat normal inspiration active breath-hold CTs were acquired weekly during radiotherapy for 9 lung cancer patients (12-21 scans per patient). A physician delineated the gross tumor volume (GTV), lungs, and spinal cord on the first breath-hold CT, and contours were propagated semiautomatically. Intra- and interfraction variability of tumor and lung position and volume were evaluated. Tumor centroid and border variability were quantified. Results: On average, intrafraction variability of lung and GTV centroid position was <2.0 mm. Interfraction population variability was 3.6-6.7 mm (systematic) and 3.1-3.9 mm (random) for the GTV centroid and 1.0-3.3 mm (systematic) and 1.5-2.6 mm (random) for the lungs. Tumor volume regressed 44.6% {+-} 23.2%. Gross tumor volume border variability was patient specific and demonstrated anisotropic shape change in some subjects. Interfraction GTV positional variability was associated with tumor volume regression and contralateral lung volume (p < 0.05). Inter-breath-hold reproducibility was unaffected by time point in the treatment course (p > 0.1). Increases in free-breathing tidal volume were associated with increases in breath-hold ipsilateral lung volume (p < 0.05). Conclusions: The breath-hold technique was reproducible within 2 mm during each fraction. Interfraction variability of GTV position and shape was substantial because of tumor volume and breath-hold lung volume change during therapy. These results support the feasibility of a hybrid breath-hold gating technique and suggest that online image guidance would be beneficial.

  20. Correlated Variability in the Breathing Pattern and End-Expiratory Lung Volumes in Conscious Humans

    PubMed Central

    Dellaca, Raffaele L.; Aliverti, Andrea; Lo Mauro, Antonella; Lutchen, Kenneth R.; Pedotti, Antonio; Suki, Bela

    2015-01-01

    In order to characterize the variability and correlation properties of spontaneous breathing in humans, the breathing pattern of 16 seated healthy subjects was studied during 40 min of quiet breathing using opto-electronic plethysmography, a contactless technology that measures total and compartmental chest wall volumes without interfering with the subjects breathing. From these signals, tidal volume (VT), respiratory time (TTOT) and the other breathing pattern parameters were computed breath-by-breath together with the end-expiratory total and compartmental (pulmonary rib cage and abdomen) chest wall volume changes. The correlation properties of these variables were quantified by detrended fluctuation analysis, computing the scaling exponentα. VT, TTOT and the other breathing pattern variables showed α values between 0.60 (for minute ventilation) to 0.71 (for respiratory rate), all significantly lower than the ones obtained for end-expiratory volumes, that ranged between 1.05 (for rib cage) and 1.13 (for abdomen) with no significant differences between compartments. The much stronger long-range correlations of the end expiratory volumes were interpreted by a neuromechanical network model consisting of five neuron groups in the brain respiratory center coupled with the mechanical properties of the respiratory system modeled as a simple Kelvin body. The model-based α for VT is 0.57, similar to the experimental data. While the α for TTOT was slightly lower than the experimental values, the model correctly predicted α for end-expiratory lung volumes (1.045). In conclusion, we propose that the correlations in the timing and amplitude of the physiological variables originate from the brain with the exception of end-expiratory lung volume, which shows the strongest correlations largely due to the contribution of the viscoelastic properties of the tissues. This cycle-by-cycle variability may have a significant impact on the functioning of adherent cells in the

  1. Breathing Maneuvers as a Vasoactive Stimulus for Detecting Inducible Myocardial Ischemia – An Experimental Cardiovascular Magnetic Resonance Study

    PubMed Central

    Fischer, Kady; Guensch, Dominik P; Shie, Nancy; Lebel, Julie; Friedrich, Matthias G

    2016-01-01

    Background Breathing maneuvers can elicit a similar vascular response as vasodilatory agents like adenosine; yet, their potential diagnostic utility in the presence of coronary artery stenosis is unknown. The objective of the study is to investigate if breathing maneuvers can non-invasively detect inducible ischemia in an experimental animal model when the myocardium is imaged with oxygenation-sensitive cardiovascular magnetic resonance (OS-CMR). Methods and Findings In 11 anesthetised swine with experimentally induced significant stenosis (fractional flow reserve <0.75) of the left anterior descending coronary artery (LAD) and 9 control animals, OS-CMR at 3T was performed during two different breathing maneuvers, a long breath-hold; and a combined maneuver of 60s of hyperventilation followed by a long breath-hold. The resulting change of myocardial oxygenation was compared to the invasive measurements of coronary blood flow, blood gases, and oxygen extraction. In control animals, all breathing maneuvers could significantly alter coronary blood flow as hyperventilation decreased coronary blood flow by 34±23%. A long breath-hold alone led to an increase of 97±88%, while the increase was 346±327% (p<0.001), when the long breath-hold was performed after hyperventilation. In stenosis animals, the coronary blood flow response was attenuated after both hyperventilation and the following breath-hold. This was matched by the observed oxygenation response as breath-holds following hyperventilation consistently yielded a significant difference in the signal of the MRI images between the perfusion territory of the stenosis LAD and remote myocardium. There was no difference between the coronary territories during the other breathing maneuvers or in the control group at any point. Conclusion In an experimental animal model, the response to a combined breathing maneuver of hyperventilation with subsequent breath-holding is blunted in myocardium subject to significant coronary

  2. Effects of breathing patterns and light exercise on linear and nonlinear heart rate variability.

    PubMed

    Weippert, Matthias; Behrens, Kristin; Rieger, Annika; Kumar, Mohit; Behrens, Martin

    2015-08-01

    Despite their use in cardiac risk stratification, the physiological meaning of nonlinear heart rate variability (HRV) measures is not well understood. The aim of this study was to elucidate effects of breathing frequency, tidal volume, and light exercise on nonlinear HRV and to determine associations with traditional HRV indices. R-R intervals, blood pressure, minute ventilation, breathing frequency, and respiratory gas concentrations were measured in 24 healthy male volunteers during 7 conditions: voluntary breathing at rest, and metronome guided breathing (0.1, 0.2 and 0.4 Hz) during rest, and cycling, respectively. The effect of physical load was significant for heart rate (HR; p < 0.001) and traditional HRV indices SDNN, RMSSD, lnLFP, and lnHFP (p < 0.01 for all). It approached significance for sample entropy (SampEn) and correlation dimension (D2) (p < 0.1 for both), while HRV detrended fluctuation analysis (DFA) measures DFAα1 and DFAα2 were not affected by load condition. Breathing did not affect HR but affected all traditional HRV measures. D2 was not affected by breathing; DFAα1 was moderately affected by breathing; and DFAα2, approximate entropy (ApEn), and SampEn were strongly affected by breathing. DFAα1 was strongly increased, whereas DFAα2, ApEn, and SampEn were decreased by slow breathing. No interaction effect of load and breathing pattern was evident. Correlations to traditional HRV indices were modest (r from -0.14 to -0.67, p < 0.05 to <0.01). In conclusion, while light exercise does not significantly affect short-time HRV nonlinear indices, respiratory activity has to be considered as a potential contributor at rest and during light dynamic exercise.

  3. Effects of breathing patterns and light exercise on linear and nonlinear heart rate variability.

    PubMed

    Weippert, Matthias; Behrens, Kristin; Rieger, Annika; Kumar, Mohit; Behrens, Martin

    2015-08-01

    Despite their use in cardiac risk stratification, the physiological meaning of nonlinear heart rate variability (HRV) measures is not well understood. The aim of this study was to elucidate effects of breathing frequency, tidal volume, and light exercise on nonlinear HRV and to determine associations with traditional HRV indices. R-R intervals, blood pressure, minute ventilation, breathing frequency, and respiratory gas concentrations were measured in 24 healthy male volunteers during 7 conditions: voluntary breathing at rest, and metronome guided breathing (0.1, 0.2 and 0.4 Hz) during rest, and cycling, respectively. The effect of physical load was significant for heart rate (HR; p < 0.001) and traditional HRV indices SDNN, RMSSD, lnLFP, and lnHFP (p < 0.01 for all). It approached significance for sample entropy (SampEn) and correlation dimension (D2) (p < 0.1 for both), while HRV detrended fluctuation analysis (DFA) measures DFAα1 and DFAα2 were not affected by load condition. Breathing did not affect HR but affected all traditional HRV measures. D2 was not affected by breathing; DFAα1 was moderately affected by breathing; and DFAα2, approximate entropy (ApEn), and SampEn were strongly affected by breathing. DFAα1 was strongly increased, whereas DFAα2, ApEn, and SampEn were decreased by slow breathing. No interaction effect of load and breathing pattern was evident. Correlations to traditional HRV indices were modest (r from -0.14 to -0.67, p < 0.05 to <0.01). In conclusion, while light exercise does not significantly affect short-time HRV nonlinear indices, respiratory activity has to be considered as a potential contributor at rest and during light dynamic exercise. PMID:26187271

  4. Use of Variable Pressure Suits, Intermittent Recompression and Nitrox Breathing Mixtures during Lunar Extravehicular Activities

    NASA Technical Reports Server (NTRS)

    Gernhardt, Michael L.; Abercromby, Andrew F.

    2009-01-01

    This slide presentation reviews the use of variable pressure suits, intermittent recompression and Nitrox breathing mixtures to allow for multiple short extravehicular activities (EVAs) at different locations in a day. This new operational concept of multiple short EVAs requires short purge times and shorter prebreathes to assure rapid egress with a minimal loss of the vehicular air. Preliminary analysis has begun to evaluate the potential benefits of the intermittent recompression, and Nitrox breathing mixtures when used with variable pressure suits to enable reduce purges and prebreathe durations.

  5. [Blood pressure variability and cardiovascular morbimortality].

    PubMed

    Robles, N R

    2000-01-01

    Blood pressure is a changing parameter that is influenced by intrinsic body rhythms, physical and emotional environmental factors that act on the individual, and the differences produced by activity and rest periods of every subject. Blood pressure variability seems to be related with target organ damage due to high blood pressure. Its specific effect on left ventricular mass is likely, although it is not absolutely confirmed. Testing blood pressure variability should be a routine exploration in patients with a target organ lesion.

  6. Variability of within-breath reactance in COPD patients and its association with dyspnoea.

    PubMed

    Aarli, Bernt B; Calverley, Peter M A; Jensen, Robert L; Eagan, Tomas M L; Bakke, Per S; Hardie, Jon A

    2015-03-01

    The forced oscillation technique can identify expiratory flow limitation (EFL) when a large difference in inspiratory and expiratory reactance (ΔXrs) occurs. However, flow limitation can vary from breath to breath, and so we compared a multiple-breath ΔXrs approach to the traditional breath-by-breath assessment of EFL. We investigated the within- and between-day reproducibility and the factors that affect the size of ΔXrs when used as a continuous measurement over multiple breaths. In addition, we examined how multiple-breath ΔXrs relates to the sensation of breathlessness. 425 moderate to very severe chronic obstructive pulmonary disease (COPD) patients and 229 controls were included. Spirometry and impedance measurements were performed on a MasterScope CT Impulse Oscillation System. Median ΔXrs approached zero in healthy controls with little variation between measurements. COPD patients generally had higher ΔXrs and higher variability. The COPD patients with ΔXrs >0.1 kPa · L(-1) · s(-1) were prone to be more breathless and had a higher modified Medical Research Council dyspnoea scale score. In controls, the 95th percentile of ΔXrs was as low as 0.07 kPa · L(-1) · s(-1). We describe a new method to assess EFL at a patient level and propose a cut-off, mean ΔXrs >0.1 kPa · L(-1) · s(-1), as a way to identify COPD patients who are more likely to report dyspnoea.

  7. Variability of within-breath reactance in COPD patients and its association with dyspnoea.

    PubMed

    Aarli, Bernt B; Calverley, Peter M A; Jensen, Robert L; Eagan, Tomas M L; Bakke, Per S; Hardie, Jon A

    2015-03-01

    The forced oscillation technique can identify expiratory flow limitation (EFL) when a large difference in inspiratory and expiratory reactance (ΔXrs) occurs. However, flow limitation can vary from breath to breath, and so we compared a multiple-breath ΔXrs approach to the traditional breath-by-breath assessment of EFL. We investigated the within- and between-day reproducibility and the factors that affect the size of ΔXrs when used as a continuous measurement over multiple breaths. In addition, we examined how multiple-breath ΔXrs relates to the sensation of breathlessness. 425 moderate to very severe chronic obstructive pulmonary disease (COPD) patients and 229 controls were included. Spirometry and impedance measurements were performed on a MasterScope CT Impulse Oscillation System. Median ΔXrs approached zero in healthy controls with little variation between measurements. COPD patients generally had higher ΔXrs and higher variability. The COPD patients with ΔXrs >0.1 kPa · L(-1) · s(-1) were prone to be more breathless and had a higher modified Medical Research Council dyspnoea scale score. In controls, the 95th percentile of ΔXrs was as low as 0.07 kPa · L(-1) · s(-1). We describe a new method to assess EFL at a patient level and propose a cut-off, mean ΔXrs >0.1 kPa · L(-1) · s(-1), as a way to identify COPD patients who are more likely to report dyspnoea. PMID:25359342

  8. Vagal-dependent nonlinear variability in the respiratory pattern of anesthetized, spontaneously breathing rats

    PubMed Central

    Dhingra, R. R.; Jacono, F. J.; Fishman, M.; Loparo, K. A.; Rybak, I. A.

    2011-01-01

    Physiological rhythms, including respiration, exhibit endogenous variability associated with health, and deviations from this are associated with disease. Specific changes in the linear and nonlinear sources of breathing variability have not been investigated. In this study, we used information theory-based techniques, combined with surrogate data testing, to quantify and characterize the vagal-dependent nonlinear pattern variability in urethane-anesthetized, spontaneously breathing adult rats. Surrogate data sets preserved the amplitude distribution and linear correlations of the original data set, but nonlinear correlation structure in the data was removed. Differences in mutual information and sample entropy between original and surrogate data sets indicated the presence of deterministic nonlinear or stochastic non-Gaussian variability. With vagi intact (n = 11), the respiratory cycle exhibited significant nonlinear behavior in templates of points separated by time delays ranging from one sample to one cycle length. After vagotomy (n = 6), even though nonlinear variability was reduced significantly, nonlinear properties were still evident at various time delays. Nonlinear deterministic variability did not change further after subsequent bilateral microinjection of MK-801, an N-methyl-d-aspartate receptor antagonist, in the Kölliker-Fuse nuclei. Reversing the sequence (n = 5), blocking N-methyl-d-aspartate receptors bilaterally in the dorsolateral pons significantly decreased nonlinear variability in the respiratory pattern, even with the vagi intact, and subsequent vagotomy did not change nonlinear variability. Thus both vagal and dorsolateral pontine influences contribute to nonlinear respiratory pattern variability. Furthermore, breathing dynamics of the intact system are mutually dependent on vagal and pontine sources of nonlinear complexity. Understanding the structure and modulation of variability provides insight into disease effects on respiratory

  9. Variability of exhaled breath condensate (EBC) volume and pH using a feedback regulated breathing pattern

    EPA Science Inventory

    Exhaled breath condensate (EBC) is a valuable biological medium for non-invasively measuring biomarkers with the potential to reflect organ systems responses to environmental and dietary exposures and disease processes. Collection of EBC has typically been with spontaneous breat...

  10. High spatial and temporal resolution retrospective cine cardiovascular magnetic resonance from shortened free breathing real-time acquisitions

    PubMed Central

    2013-01-01

    Background Cine cardiovascular magnetic resonance (CMR) is challenging in patients who cannot perform repeated breath holds. Real-time, free-breathing acquisition is an alternative, but image quality is typically inferior. There is a clinical need for techniques that achieve similar image quality to the segmented cine using a free breathing acquisition. Previously, high quality retrospectively gated cine images have been reconstructed from real-time acquisitions using parallel imaging and motion correction. These methods had limited clinical applicability due to lengthy acquisitions and volumetric measurements obtained with such methods have not previously been evaluated systematically. Methods This study introduces a new retrospective reconstruction scheme for real-time cine imaging which aims to shorten the required acquisition. A real-time acquisition of 16-20s per acquired slice was inputted into a retrospective cine reconstruction algorithm, which employed non-rigid registration to remove respiratory motion and SPIRiT non-linear reconstruction with temporal regularization to fill in missing data. The algorithm was used to reconstruct cine loops with high spatial (1.3-1.8 × 1.8-2.1 mm2) and temporal resolution (retrospectively gated, 30 cardiac phases, temporal resolution 34.3 ± 9.1 ms). Validation was performed in 15 healthy volunteers using two different acquisition resolutions (256 × 144/192 × 128 matrix sizes). For each subject, 9 to 12 short axis and 3 long axis slices were imaged with both segmented and real-time acquisitions. The retrospectively reconstructed real-time cine images were compared to a traditional segmented breath-held acquisition in terms of image quality scores. Image quality scoring was performed by two experts using a scale between 1 and 5 (poor to good). For every subject, LAX and three SAX slices were selected and reviewed in the random order. The reviewers were blinded to the reconstruction approach and

  11. Override of spontaneous respiratory pattern generator reduces cardiovascular parasympathetic influence

    NASA Technical Reports Server (NTRS)

    Patwardhan, A. R.; Vallurupalli, S.; Evans, J. M.; Bruce, E. N.; Knapp, C. F.

    1995-01-01

    We investigated the effects of voluntary control of breathing on autonomic function in cardiovascular regulation. Variability in heart rate was compared between 5 min of spontaneous and controlled breathing. During controlled breathing, for 5 min, subjects voluntarily reproduced their own spontaneous breathing pattern (both rate and volume on a breath-by-breath basis). With the use of this experimental design, we could unmask the effects of voluntary override of the spontaneous respiratory pattern generator on autonomic function in cardiovascular regulation without the confounding effects of altered respiratory pattern. Results from 10 subjects showed that during voluntary control of breathing, mean values of heart rate and blood pressure increased, whereas fractal and spectral powers in heart rate in the respiratory frequency region decreased. End-tidal PCO2 was similar during spontaneous and controlled breathing. These results indicate that the act of voluntary control of breathing decreases the influence of the vagal component, which is the principal parasympathetic influence in cardiovascular regulation.

  12. Effect of breakfast on selected serum and cardiovascular variables

    NASA Technical Reports Server (NTRS)

    Frey, Mary A. B.; Merz, Marion P.; Hoffler, G. W.

    1992-01-01

    In view of the objections of many subjects to overnight fasting prior to their blood being drawn for analyses, the effect of eating breakfast on the results of subsequent blood analyses of selected blood constituents and on cardiovascular variables was investigated in 47 men and 34 women who were subjected to blood analyses on two occasions, one week apart: once fasting and once after breakfast. Results suggest that subjects need not fast overnight before blood is being drawn for determinations of the HDL-C levels, hemoglobin, hematocrit, total cholesterol, or phosphorus. However, based on other studies, it is suggested breakfast should not have a high content of fat.

  13. Slow breathing influences cardiac autonomic responses to postural maneuver: Slow breathing and HRV.

    PubMed

    Vidigal, Giovanna Ana de Paula; Tavares, Bruna S; Garner, David M; Porto, Andrey A; Carlos de Abreu, Luiz; Ferreira, Celso; Valenti, Vitor E

    2016-05-01

    Chronic slow breathing has been reported to improve Heart Rate Variability (HRV) in patients with cardiovascular disorders. However, it is not clear regarding its acute effects on HRV responses on autonomic analysis. We evaluated the acute effects of slow breathing on cardiac autonomic responses to postural change manoeuvre (PCM). The study was conducted on 21 healthy male students aged between 18 and 35 years old. In the control protocol, the volunteer remained at rest seated for 15 min under spontaneous breathing and quickly stood up within 3 s and remained standing for 15 min. In the slow breathing protocol, the volunteer remained at rest seated for 10 min under spontaneous breath, then performed slow breathing for 5 min and rapidly stood up within 3 s and remained standing for 15 min. Slow breathing intensified cardiac autonomic responses to postural maneuver. PMID:27157952

  14. Cardiovascular change in elderly male breath-hold divers (Ama) and their socio-economical background at Chikura in Japan.

    PubMed

    Holm, B; Schagatay, E; Kobayashi, T; Masuda, A; Ohdaira, T; Honda, Y

    1998-09-01

    The Ama have existed for more than 2000 years in Japan and Korea. They have been diving for seaweed and molluscs. Their traditional way of fishing, with goggles or a mask, but without a wetsuit, is still practised as a result of laws against overfishing. We investigated cardiovascular diving responses, expressed as heart rate (HR) reduction, peripheral vasoconstriction indicated by skin blood flow (SkBF) and mean arterial blood pressure (MAP) during breath-hold face immersion in a group of eight elderly male Ama at Chikura, Japan. Their data were compared to those from three other groups: a) elderly non-divers; b) young divers and c) young non-divers. Our previous studies have shown that young divers show a more pronounced bradycardia than young non-divers. The present study of elderly Ama and elderly non-divers was performed to investigate if this difference persists in old age. We found that, in spite of many years of diving experience, HR reduction of the elderly professional divers observed during face immersion did not differ from that of elderly non-divers, but it was much less pronounced than in the two younger groups. We conclude that even if a well-developed diving response at young age has been reduced to the level of non-divers, the Ama are still able to continue their work of diving in old age. Ama that has been a traditionally female occupation, is mostly practised by men at Chikura today. No young have been recruited for this profession. Therefore, the present Ama are senior and the traditional breath-hold diving will probably cease to exist in the near future. The probable reasons for these changes are discussed.

  15. Arrhythmogenic properties of disordered breathing during sleep in patients with cardiovascular disorders.

    PubMed

    Otsuka, K; Sadakane, N; Ozawa, T

    1987-12-01

    The purpose of this study was twofold: to establish an ECG respiration monitoring system, and to evaluate the clinical usefulness of this system. Our purpose was to determine how many patients with cardiovascular disorders may have unrecognized sleep apnea and whether such apneic episodes are an important cause of cardiac arrhythmias. The study group included 81 patients, age range 40-95 years, and 13 healthy males, age range 52-72 years. The 24-h ECG respiration recordings were obtained with the two-channel holter recorder. Airflow at the nose using a nasal thermister or chest wall movement by impedance pneumography was recorded as respiration record on the second channel. Sleep apnea was observed 69% and 77-100% in the control subjects and patients with cardiovascular disorders, respectively. Episodes of sleep apnea were most frequent in the patients with old myocardial infarction. Grading of apneas was defined according to the length of apnea. Short duration apneas were observed only in the control subjects, but longer apneic episodes were observed in patients with cardiovascular disorders. Bradyarrhythmias observed were to be relative to apneic episodes longer than 20 s, while ventricular arrhythmias were observed only in the patients with old myocardial infarction, coincident with apneas lasting longer than 40 s. Atrioventricular conduction disturbances were also observed to be related to the occurrence of sleep apnea. These results suggest that 24-h ECG respiration monitoring is useful not only for the observation of sleep apneic episodes, but also in clarifying the relationship between cardiac arrhythmias and apneic episodes.

  16. Cardiovascular changes during deep breath-hold dives in a pressure chamber.

    PubMed

    Ferrigno, M; Ferretti, G; Ellis, A; Warkander, D; Costa, M; Cerretelli, P; Lundgren, C E

    1997-10-01

    Electrocardiogram, cardiac output, and blood lactate accumulation were recorded in three elite breath-hold divers diving to 40-55 m in a pressure chamber in thermoneutral (35 degrees C) or cool (25 degrees C) water. In two of the divers, invasive recordings of arterial blood pressure were also obtained during dives to 50 m in cool water. Bradycardia during the dives was more pronounced and developed more rapidly in the cool water, with heart rates dropping to 20-30 beats/min. Arrhythmias occurred, particularly during the dives in cool water, when they were often more frequent than sinus beats. Because of bradycardia, cardiac output decreased during the dives, especially in cool water (to <3 l/min in 2 of the divers). Arterial blood pressure increased dramatically, reaching values as high as 280/200 and 290/150 mmHg in the two divers, respectively. This hypertension was secondary to peripheral vasoconstriction, which also led to anaerobic metabolism, reflected in increased blood lactate concentration. The diving response of these divers resembles the one described for diving animals, although the presence of arrhythmias and large increases in blood pressure indicate a less perfect adaptation in humans.

  17. Cardiovascular anatomy and cardiac function in the air-breathing swamp eel (Monopterus albus).

    PubMed

    Iversen, Nina K; Lauridsen, Henrik; Do, Thi Thanh Huong; Nguyen, Van Cong; Gesser, Hans; Buchanan, Rasmus; Bayley, Mark; Pedersen, Michael; Wang, Tobias

    2013-01-01

    Monopterus albus, a swamp eel inhabiting the freshwaters of South East Asia, relies on an extensive vascularisation of the buccal cavity, pharynx and anterior oesophagus for gas exchange, while the gills are much reduced. In the present study we describe the macro-circulation in the cephalic region and the vascularisation of the buccal cavity of M. albus using vascular fillings and micro-computed tomography (μCT). We also show that M. albus has the capacity to use the buccal cavity for aquatic gas exchange, being able to maintain normal arterial blood gas composition, blood pressure, heart rate and cardiac output throughout 10h of forced submergence. M. albus therefore can be characterised as a facultative air-breather. Because M. albus aestivates for many months in moist mud during the dry season we characterised in vivo cardiovascular function during exposure to anoxia as well as the effects of anoxia on in vitro contractility of strip preparations from atria and ventricle. Both studies revealed a low anoxia tolerance, rendering it unlikely that M. albus can survive prolonged exposure to anoxia.

  18. Causal coherence analysis of cardiovascular variables in obese preadolescents and adolescents.

    PubMed

    Javorka, Michal; Czippelova, Barbora; Turianikova, Zuzana; Lazarova, Zuzana; Tonhajzerova, Ingrid; Javorka, Kamil; Baumert, Mathias

    2015-08-01

    Obesity during adulthood has been associated with cardiovascular disease, but its adverse effects during adolescence are less well established. The aim of this study was to probe cardiovascular control in obese adolescence by studying causal coherence between cardiovascular variables. Sixty minutes of resting ECG and finger blood pressure were recorded in 19 obese and 19 non-obese subjects in the supine position to measure pair-wise spectral coherence in the low frequency band between heart rate, systolic and diastolic blood pressure, pulse pressure, total peripheral resistance and left ventricular ejection time. We observed that causal coherences in {systolic blood pressure → total peripheral resistance} and {left ventricular ejection time → systolic blood pressure} directions were significantly decreased in obese preadolescents and adolescents when compared to the healthy control group, despite the lack of difference in the magnitude of oscillations of cardiovascular variables. In conclusion, causal coherence analysis of cardiovascular variables may give new insight into cardiovascular dysregulation in young obese subjects.

  19. Heart Rate Variability and Sleep-Related Breathing Disorders in the General Population.

    PubMed

    Aeschbacher, Stefanie; Bossard, Matthias; Schoen, Tobias; Schmidlin, Delia; Muff, Christoph; Maseli, Anna; Leuppi, Jörg D; Miedinger, David; Probst-Hensch, Nicole M; Schmidt-Trucksäss, Arno; Risch, Martin; Risch, Lorenz; Conen, David

    2016-09-15

    Obstructive sleep apnea seems to have an important influence on the autonomic nervous system. In this study, we assessed the relations of sleep apnea-related parameters with 24-hour heart rate variability (HRV) in a large population of young and healthy adults. Participants aged 25 to 41 years with a body mass index <35 kg/m(2) and without known obstructive sleep apnea were included in a prospective population-based cohort study. HRV was assessed using 24-hour electrocardiographic monitoring. The SD of all normal RR intervals (SDNN) was used as the main HRV variable. Apnea-Hypopnea Index (AHI) and oxygen desaturation index (ODI) were obtained from nighttime pulse oximetry with nasal airflow measurements. We defined sleep-related breathing disorders as an AHI ≥5 or an ODI ≥5. Multivariable regression models were constructed to assess the relation of HRV with either AHI or ODI. Median age of the 1,255 participants was 37 years, 47% were men, and 9.6% had an AHI ≥5. Linear inverse associations of SDNN across AHI and ODI groups were found (p for trend = 0.006 and 0.0004, respectively). The β coefficients (95% CI) for the relation between SDNN and elevated AHI were -0.20 (-0.40 to -0.11), p = 0.04 and -0.29 (-0.47 to -0.11), p = 0.002 for elevated ODI. After adjustment for 24-hour heart rate, the same β coefficients (95% CI) were -0.06 (-0.22 to 0.11), p = 0.51 and -0.14 (-0.30 to 0.01), p = 0.07, respectively. In conclusion, even early stages of sleep-related breathing disorders are inversely associated with HRV in young and healthy adults, suggesting that they are tightly linked with autonomic dysfunction. However, HRV and 24-hour heart rate seem to have common information. PMID:27553103

  20. Range of control of cardiovascular variables by the hypothalamus

    NASA Technical Reports Server (NTRS)

    Smith, O. A.; Stephenson, R. B.; Randall, D. C.

    1974-01-01

    New methodologies were utilized to study the influence of the hypothalamus on the cardiovascular system. The regulation of myocardial activity was investigated in monkeys with hypothalamic lesions that eliminate cardiovascular responses. Observations showed that a specific part of the hypothalamus regulates changes in myocardial contractility that accompanies emotion. Studies of the hypothalamus control of renal blood flow showed the powerful potential control of this organ over renal circulation.

  1. Variability in the blood/breath alcohol ratio and implications for evidentiary purposes.

    PubMed

    Jaffe, Dena H; Siman-Tov, Maya; Gopher, Asher; Peleg, Kobi

    2013-09-01

    The breath analyzer is an indispensable tool for identifying alcohol levels among drivers. While numerous studies have shown high correlations between blood and breath alcohol concentrations, most are limited by the study design. This study seeks to assess this relationship by minimizing potential measurement bias, document time from alcohol consumption to testing, and adjusting for potential confounders. A blinded study was performed using conditions closely resembling those in the field. The Draeger 7110 MKIII IL breath analyzer was used to assess breath alcohol concentrations (BrAC). Participants were 61 healthy volunteers aged 21-37 years with body mass index ≤30 and no history of alcoholism. A total of 242 valid blood/breath tests were performed in four test sets. The study results showed a high correlation coefficient between BrAC and blood alcohol concentration (BAC) levels (r = 0.983) with high sensitivity (97%) and specificity (93%). This strong association between the breath analyzer and BAC persisted even after adjustment for various stages of alcohol absorption. These results illustrate the high diagnostic sensitivity of the breath analyzer in field-tested conditions.

  2. Sleep-related breathing disorders and gait variability: a cross-sectional preliminary study

    PubMed Central

    2014-01-01

    Background Sleep-related breathing disorders (SRBDs) provoke cognitive and structural brain disorders. Because these disorders have been associated with unsafe gait characterized by an increase in stride-to-stride variability of stride time (STV), we hypothesised that SRBDs could be associated with an increased STV. The aim of this study was to examine the association between SRBDs and STV in French healthy older community-dwellers. Methods A total of 49 participants (mean age 69.6 ± 0.8years; 65.2% female) were included in this cross-sectional study. All participants, who were free of clinically diagnosed SRBDs before their inclusion, had a nocturnal unattended home-sleep assessment. There were separated in three group based on apnea + hypopnea index (AHI): AHI <15 defining the absence of SRBD, AHI between 15–30 defining mild SRBD, and AHI >30 defining moderate-to-severe SRBD. Coefficient of variation of stride time, which is a measure of STV, was recorded while usual walking using SMTEC® footswitches system. Digit span score was used as a measure of executive performance. Age, gender, body mass index (BMI), number of drugs daily taken, vision, proprioception, history of falls, depression symptoms, global cognitive functioning were also recorded. Results STV and BMI were higher in participants with mild SRBDs (P = 0.031 and P = 0.020) and moderate-to-severe SRBDs (P = 0.004 and P = 0.002) compared to non-SRBDs. STV positively correlated with AHI (P = 0.036). Lower (i.e., better) STV was associated with the absence of SRBDs (P = 0.021), while greater (i.e., worse) STV was associated with moderate-to-severe SRBD (P < 0.045) but not with mild SRBD (P > 0.06). Conclusion Our results show a positive association between STV and SRBDs, with moderate-to-severe SRBD being associated with greater gait variability. This association opens new perspectives for understanding gait disorders in older adults with SRBDs and opens the door

  3. Accounting for respiration is necessary to reliably infer Granger causality from cardiovascular variability series.

    PubMed

    Porta, Alberto; Bassani, Tito; Bari, Vlasta; Pinna, Gian D; Maestri, Roberto; Guzzetti, Stefano

    2012-03-01

    This study was designed to demonstrate the need of accounting for respiration (R) when causality between heart period (HP) and systolic arterial pressure (SAP) is under scrutiny. Simulations generated according to a bivariate autoregressive closed-loop model were utilized to assess how causality changes as a function of the model parameters. An exogenous (X) signal was added to the bivariate autoregressive closed-loop model to evaluate the bias on causality induced when the X source was disregarded. Causality was assessed in the time domain according to a predictability improvement approach (i.e., Granger causality). HP and SAP variability series were recorded with R in 19 healthy subjects during spontaneous and controlled breathing at 10, 15, and 20 breaths/min. Simulations proved the importance of accounting for X signals. During spontaneous breathing, assessing causality without taking into consideration R leads to a significantly larger percentage of closed-loop interactions and a smaller fraction of unidirectional causality from HP to SAP. This finding was confirmed during paced breathing and it was independent of the breathing rate. These results suggest that the role of baroreflex cannot be correctly assessed without accounting for R.

  4. Measuring Breathing Rate Variability by a Microprocessor Based Instrument in Newborn Infants

    PubMed Central

    Dolcourt, Jack; Younger, Steve

    1984-01-01

    A microprocessor-based instrument was developed to measure apnea (cessation of breathing) of prematurity. This instrument analyzes real-time respiratory data obtrained from either a standard cardiorespiratory monitor or from an end-tidal CO2 analyzer. The time between successive breaths (apneic duration) is computed and recorded. These intervals are displayed as a histogram in real-time on a computer terminal screen. The effects of pharmacologic treatment and nervous system maturation as relating to respiratory instability in premature infants is demonstrated.

  5. Inter- and Intrafraction Variability in Liver Position in Non-Breath-Hold Stereotactic Body Radiotherapy

    SciTech Connect

    Case, Robert B.; Sonke, Jan-Jakob; Moseley, Douglas J.; Kim, John; Brock, Kristy K.; Dawson, Laura A.

    2009-09-01

    Purpose: The inter- and intrafraction variability of liver position was assessed in patients with liver cancer treated with kilovoltage cone-beam computed tomography (CBCT)-guided stereotactic body radiotherapy. Methods and Materials: A total of 314 CBCT scans obtained in the treatment position immediately before and after each fraction were evaluated from 29 patients undergoing six-fraction, non-breath-hold stereotactic body radiotherapy for unresectable liver cancer. Off-line, the CBCT scans were sorted into 10 bins, according to the phase of respiration. The liver position (relative to the vertebral bodies) was measured using rigid alignment of the exhale CBCT liver with the exhale planning CT liver, following the alignment of the vertebrae. The interfraction liver position change was measured by comparing the pretreatment CBCT scans, and the intrafraction change was measured from the CBCT scans obtained immediately before and after each fraction. Results: The mean amplitude of liver motion for all patients was 1.8 mm (range, 0.1-5.7), 8.0 mm (range, 0.1-18.8), and 4.3 mm (range 0.1-12.1) in the medial-lateral (ML), craniocaudal (CC), and anteroposterior (AP) directions, respectively. The mean absolute ML, CC, and AP interfraction changes in liver position were 2.0 mm (90th percentile, 4.2), 3.5 mm (90th percentile, 7.3), and 2.3 mm (90th percentile, 4.7). The mean absolute intrafraction ML, CC, and AP changes were 1.3 mm (90th percentile, 2.9), 1.6 mm (90th percentile, 3.6), and 1.5 mm (90th percentile, 3.1), respectively. The interfraction changes were significantly larger than the intrafraction changes, with a CC systematic error of 2.9 and 1.1 mm, respectively. The intraobserver reproducibility ({sigma}, n = 29 fractions) was 1.3 mm in the ML, 1.4 mm in the CC, and 1.6 mm in the AP direction. Conclusion: Interfraction liver position changes relative to the vertebral bodies are an important source of geometric uncertainty, providing a rationale for

  6. Heart rate variability during static and dynamic breath-hold dives in elite divers.

    PubMed

    Kiviniemi, Antti M; Breskovic, Toni; Uglesic, Lovro; Kuch, Benjamin; Maslov, Petra Zubin; Sieber, Arne; Seppänen, Tapio; Tulppo, Mikko P; Dujic, Zeljko

    2012-08-16

    The purpose of this study was to assess the differences in cardiac autonomic modulation during maximal static (SA) and dynamic (DA) underwater apneas. Arterial oxygen saturation (SpO(2)), heart rate (HR) and HR variability (SD1 from Poincaré plot and short-term fractal-like scaling exponent, α(1)) were analyzed at the immersed baseline (3 min) and initial, mid- and end-phases (each 30s) of SA and DA in nine elite breath-hold divers. DA and SA lasted 78 ± 8 and 225 ± 20s (mean ± SEM), respectively, and resulted in similar decrements in end-stage SpO(2) (78 ± 3 and 75 ± 3%, p=0.352). During DA, initial increase in HR (from 80 ± 5 to 122 ± 5 bpm, p<0.001) was followed by gradual decrease towards the baseline at mid-apnea and end-apnea phase (101 ± 6 and 80 ± 8 bpm, respectively). During SA, HR decreased at mid-apnea (from 78 ± 4 to 66 ± 3 bpm, p=0.004) but did not decrease further at end-apnea phase (66 ± 4b pm). Decreased SD1 was observed at the initial phase of DA (from 28 ± 5 to 10 ± 4 ms, p=0.005) being lower compared with SA (24 ± 4 ms, p=0.005). At the end of DA and SA, SD1 tended to increase above the baseline (62 ± 16 and 66 ± 10 ms, p=0.128 and p=0.093, respectively, p=0.602 DA vs. SA). α(1) tended to be higher at the end of DA compared with SA (1.17 ± 0.10 vs. 0.79 ± 0.10, p=0.059). We concluded that apnea blunts the effects of exercise on cardiac vagal activity at the end of DA. However, higher HR during DA compared with SA indicates larger cardiac sympathetic activity during DA, as suggested also by slightly higher α(1).

  7. Variables that Impact on the Results of Breath-Alcohol Tests

    ERIC Educational Resources Information Center

    Labianca, Dominick A.

    2004-01-01

    In a 2003 issue of the "Journal of Chemical Education," Kniesel and Bellamy describe a timely and pedagogically effective experiment involving breath-alcohol analysis using an FTIR (Fourier Transform Infrared Spectroscopy) spectrometer. The present article clarifies some of the information presented in the 2003 article.

  8. Blood pressure variability and cardiovascular disease: systematic review and meta-analysis

    PubMed Central

    Wood, Sally; Koshiaris, Constantinos; Law, Kathryn; Glasziou, Paul; McManus, Richard J

    2016-01-01

    Objective To systematically review studies quantifying the associations of long term (clinic), mid-term (home), and short term (ambulatory) variability in blood pressure, independent of mean blood pressure, with cardiovascular disease events and mortality. Data sources Medline, Embase, Cinahl, and Web of Science, searched to 15 February 2016 for full text articles in English. Eligibility criteria for study selection Prospective cohort studies or clinical trials in adults, except those in patients receiving haemodialysis, where the condition may directly impact blood pressure variability. Standardised hazard ratios were extracted and, if there was little risk of confounding, combined using random effects meta-analysis in main analyses. Outcomes included all cause and cardiovascular disease mortality and cardiovascular disease events. Measures of variability included standard deviation, coefficient of variation, variation independent of mean, and average real variability, but not night dipping or day-night variation. Results 41 papers representing 19 observational cohort studies and 17 clinical trial cohorts, comprising 46 separate analyses were identified. Long term variability in blood pressure was studied in 24 papers, mid-term in four, and short-term in 15 (two studied both long term and short term variability). Results from 23 analyses were excluded from main analyses owing to high risks of confounding. Increased long term variability in systolic blood pressure was associated with risk of all cause mortality (hazard ratio 1.15, 95% confidence interval 1.09 to 1.22), cardiovascular disease mortality (1.18, 1.09 to 1.28), cardiovascular disease events (1.18, 1.07 to 1.30), coronary heart disease (1.10, 1.04 to 1.16), and stroke (1.15, 1.04 to 1.27). Increased mid-term and short term variability in daytime systolic blood pressure were also associated with all cause mortality (1.15, 1.06 to 1.26 and 1.10, 1.04 to 1.16, respectively). Conclusions Long term

  9. Home Blood Pressure Variability as Cardiovascular Risk Factor in the Population of Ohasama

    PubMed Central

    Asayama, Kei; Kikuya, Masahiro; Schutte, Rudolph; Thijs, Lutgarde; Hosaka, Miki; Satoh, Michihiro; Hara, Azusa; Obara, Taku; Inoue, Ryusuke; Metoki, Hirohito; Hirose, Takuo; Ohkubo, Takayoshi; Staessen, Jan A.; Imai, Yutaka

    2013-01-01

    Blood pressure variability based on office measurement predicts outcome in selected patients. We explored whether novel indices of blood pressure variability derived from the self-measured home blood pressure predicted outcome in a general population. We monitored mortality and stroke in 2421 Ohasama residents (Iwate Prefecture, Japan). At enrollment (1988–1995), participants (mean age, 58.6 years; 60.9% women; 27.1% treated) measured their blood pressure at home, using an oscillometric device. In multivariable-adjusted Cox models, we assessed the independent predictive value of the within-subject mean systolic blood pressure (SBP) and corresponding variability as estimated by variability independent of the mean, difference between maximum and minimum blood pressure, and average real variability. Over 12.0 years (median), 412 participants died, 139 of cardiovascular causes, and 223 had a stroke. In models including morning SBP, variability independent of the mean and average real variability (median, 26 readings) predicted total and cardiovascular mortality in all of the participants (P≤0.044); variability independent of the mean predicted cardiovascular mortality in treated (P=0.014) but not in untreated (P=0.23) participants; and morning maximum and minimum blood pressure did not predict any end point (P≥0.085). In models already including evening SBP, only variability independent of the mean predicted cardiovascular mortality in all and in untreated participants (P≤0.046). The R2 statistics, a measure for the incremental risk explained by adding blood pressure variability to models already including SBP and covariables, ranged from <0.01% to 0.88%. In a general population, new indices of blood pressure variability derived from home blood pressure did not incrementally predict outcome over and beyond mean SBP. PMID:23172933

  10. Cardiovascular

    NASA Video Gallery

    Overview of Cardiovascular research which addresses risks of space flight, including adaptive changes to the cephalad fluid shift (such as reduced circulating blood volume), potential for heart rhy...

  11. Variability in Ozone-Induced Pulmonary Injury and Inflammation in Healthy and Cardiovascular Compromised Rat Models

    EPA Science Inventory

    The molecular bases for variability in air pollutant-induced pulmonary injury due to underlying cardiovascular (CVD) and/or metabolic diseases are unknown. We hypothesized that healthy and genetic CVD-prone rat models will exhibit exacerbated response to acute ozone exposure depe...

  12. Systemic Hemodynamic Atherothrombotic Syndrome and Resonance Hypothesis of Blood Pressure Variability: Triggering Cardiovascular Events.

    PubMed

    Kario, Kazuomi

    2016-07-01

    Blood pressure (BP) exhibits different variabilities and surges with different time phases, from the shortest beat-by-beat to longest yearly changes. We hypothesized that the synergistic resonance of these BP variabilites generates an extraordinarily large dynamic surge in BP and triggers cardiovascular events (the resonance hypothesis). The power of pulses is transmitted to the peripheral sites without attenuation by the large arteries, in individuals with stiffened arteries. Thus, the effect of a BP surge on cardiovascular risk would be especially exaggerated in high-risk patients with vascular disease. Based on this concept, our group recently proposed a new theory of systemic hemodynamic atherothromboltic syndrome (SHATS), a vicious cycle of hemodynamic stress and vascular disease that advances organ damage and triggers cardiovascular disease. Clinical phenotypes of SHATS are large-artery atherothombotic diseases such as stroke, coronary artery disease, and aortic and pheripheral artery disease; small-artery diseases, and microcirculation-related disease such as vascular cognitive dysfunction, heart failure, and chronic kidney disease. The careful consideration of BP variability and vascular diseases such as SHATS, and the early detection and management of SHATS, will achieve more effective individualized cardiovascular protection. In the near future, information and communication technology-based 'anticipation medicine' predicted by the changes of individual BP values could be a promising approach to achieving zero cardiovascular events. PMID:27482253

  13. Systemic Hemodynamic Atherothrombotic Syndrome and Resonance Hypothesis of Blood Pressure Variability: Triggering Cardiovascular Events

    PubMed Central

    2016-01-01

    Blood pressure (BP) exhibits different variabilities and surges with different time phases, from the shortest beat-by-beat to longest yearly changes. We hypothesized that the synergistic resonance of these BP variabilites generates an extraordinarily large dynamic surge in BP and triggers cardiovascular events (the resonance hypothesis). The power of pulses is transmitted to the peripheral sites without attenuation by the large arteries, in individuals with stiffened arteries. Thus, the effect of a BP surge on cardiovascular risk would be especially exaggerated in high-risk patients with vascular disease. Based on this concept, our group recently proposed a new theory of systemic hemodynamic atherothromboltic syndrome (SHATS), a vicious cycle of hemodynamic stress and vascular disease that advances organ damage and triggers cardiovascular disease. Clinical phenotypes of SHATS are large-artery atherothombotic diseases such as stroke, coronary artery disease, and aortic and pheripheral artery disease; small-artery diseases, and microcirculation-related disease such as vascular cognitive dysfunction, heart failure, and chronic kidney disease. The careful consideration of BP variability and vascular diseases such as SHATS, and the early detection and management of SHATS, will achieve more effective individualized cardiovascular protection. In the near future, information and communication technology-based 'anticipation medicine' predicted by the changes of individual BP values could be a promising approach to achieving zero cardiovascular events. PMID:27482253

  14. Can Ambulatory Blood Pressure Variability Contribute to Individual Cardiovascular Risk Stratification?

    PubMed Central

    Magdás, Annamária; Szilágyi, László; Incze, Alexandru

    2016-01-01

    Objective. The aim of this study is to define the normal range for average real variability (ARV) and to establish whether it can be considered as an additional cardiovascular risk factor. Methods. In this observational study, 110 treated hypertensive patients were included and admitted for antihypertensive treatment adjustment. Circadian blood pressure was recorded with validated devices. Blood pressure variability (BPV) was assessed according to the ARV definition. Based on their variability, patients were classified into low, medium, and high variability groups using the fuzzy c-means algorithm. To assess cardiovascular risk, blood samples were collected. Characteristics of the groups were compared by ANOVA tests. Results. Low variability was defined as ARV below 9.8 mmHg (32 patients), medium as 9.8–12.8 mmHg (48 patients), and high variability above 12.8 mmHg (30 patients). Mean systolic blood pressure was 131.2 ± 16.7, 135.0 ± 12.1, and 141.5 ± 11.4 mmHg in the low, medium, and high variability groups, respectively (p = 0.0113). Glomerular filtration rate was 78.6 ± 29.3, 74.8 ± 26.4, and 62.7 ± 23.2 mL/min/1.73 m2 in the low, medium, and high variability groups, respectively (p = 0.0261). Conclusion. Increased values of average real variability represent an additional cardiovascular risk factor. Therefore, reducing BP variability might be as important as achieving optimal BP levels, but there is need for further studies to define a widely acceptable threshold value. PMID:27247614

  15. Is It Daily, Monthly, or Yearly Blood Pressure Variability that Enhances Cardiovascular Risk?

    PubMed

    Dolan, Eamon; O'Brien, Eoin

    2015-11-01

    Variability is a phenomenon common to most biological processes that we can measure and is a particular feature of blood pressure (BP). Variability causes concern for many physicians regarding its clinical meaning and potential impact on cardiovascular risk. In this review, we assess the role of different time periods of blood pressure variability (BPV) in cardiovascular risk stratification. We review the indices of BPV derived from ambulatory blood pressure measurement (ABPM), home blood pressure measurement (HBPM), or at the clinic setting with the intention of providing a clear message for clinical practice. BPV, either derived from ABPM or HBPM, does not consistently augment cardiovascular risk prediction over and beyond that of average BP, particularly in low-risk individuals. That said, it would seem that certain medications such as calcium channel blockers may have a beneficial effect on visit-to-visit BPV and perhaps reduce the associated cardiovascular risk. This highlights the benefits in using combination therapy which might couple a number of therapeutic benefits such as the reductions of mean blood pressure and BPV. Overall, we should remain aware that the average BP level remains the main modifiable risk factor derived from BP measurements and continue to improve the control of hypertension and adverse health outcomes. PMID:26351017

  16. Myocardial viability: breath-hold 3D MR imaging of delayed hyperenhancement with variable sampling in time.

    PubMed

    Foo, Thomas K F; Stanley, David W; Castillo, Ernesto; Rochitte, Carlos E; Wang, Yi; Lima, João A C; Bluemke, David A; Wu, Katherine C

    2004-03-01

    A method for visualizing myocardial infarction with a three-dimensional (3D) breath-hold gated acquisition was examined. By using variable sampling in time, whole heart coverage with a single volume acquisition was achieved in 24 heart beats. In a study of 35 patients, in whom 3D volume acquisition was compared with a two-dimensional (2D) acquisition, all regions of myocardial infarction were correctly identified at 3D examination. The mean imaging time for 12 section locations was 8.0 minutes +/- 3.0 with a 2D approach compared with 22 seconds +/- 4 with a 3D approach (P <.001). Advantages were also noted for infarct contrast-to-noise ratio: 60 +/- 37 for 3D versus 33 +/- 20 for 2D imaging (P <.001). No significant differences (P >.05) were noted at qualitative assessment of myocardial suppression, endocardial border visualization, respiratory and cardiac motion artifacts, or confidence of transmurality of the infarct.

  17. Classifying geometric variability by dominant eigenmodes of deformation in regressing tumours during active breath-hold lung cancer radiotherapy.

    PubMed

    Badawi, Ahmed M; Weiss, Elisabeth; Sleeman, William C; Hugo, Geoffrey D

    2012-01-21

    The purpose of this study is to develop and evaluate a lung tumour interfraction geometric variability classification scheme as a means to guide adaptive radiotherapy and improve measurement of treatment response. Principal component analysis (PCA) was used to generate statistical shape models of the gross tumour volume (GTV) for 12 patients with weekly breath hold CT scans. Each eigenmode of the PCA model was classified as 'trending' or 'non-trending' depending on whether its contribution to the overall GTV variability included a time trend over the treatment course. Trending eigenmodes were used to reconstruct the original semi-automatically delineated GTVs into a reduced model containing only time trends. Reduced models were compared to the original GTVs by analyzing the reconstruction error in the GTV and position. Both retrospective (all weekly images) and prospective (only the first four weekly images) were evaluated. The average volume difference from the original GTV was 4.3% ± 2.4% for the trending model. The positional variability of the GTV over the treatment course, as measured by the standard deviation of the GTV centroid, was 1.9 ± 1.4 mm for the original GTVs, which was reduced to 1.2 ± 0.6 mm for the trending-only model. In 3/13 cases, the dominant eigenmode changed class between the prospective and retrospective models. The trending-only model preserved GTV and shape relative to the original GTVs, while reducing spurious positional variability. The classification scheme appears feasible for separating types of geometric variability by time trend.

  18. Classifying geometric variability by dominant eigenmodes of deformation in regressing tumours during active breath-hold lung cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Badawi, Ahmed M.; Weiss, Elisabeth; Sleeman, William C., IV; Hugo, Geoffrey D.

    2012-01-01

    The purpose of this study is to develop and evaluate a lung tumour interfraction geometric variability classification scheme as a means to guide adaptive radiotherapy and improve measurement of treatment response. Principal component analysis (PCA) was used to generate statistical shape models of the gross tumour volume (GTV) for 12 patients with weekly breath hold CT scans. Each eigenmode of the PCA model was classified as ‘trending’ or ‘non-trending’ depending on whether its contribution to the overall GTV variability included a time trend over the treatment course. Trending eigenmodes were used to reconstruct the original semi-automatically delineated GTVs into a reduced model containing only time trends. Reduced models were compared to the original GTVs by analyzing the reconstruction error in the GTV and position. Both retrospective (all weekly images) and prospective (only the first four weekly images) were evaluated. The average volume difference from the original GTV was 4.3% ± 2.4% for the trending model. The positional variability of the GTV over the treatment course, as measured by the standard deviation of the GTV centroid, was 1.9 ± 1.4 mm for the original GTVs, which was reduced to 1.2 ± 0.6 mm for the trending-only model. In 3/13 cases, the dominant eigenmode changed class between the prospective and retrospective models. The trending-only model preserved GTV and shape relative to the original GTVs, while reducing spurious positional variability. The classification scheme appears feasible for separating types of geometric variability by time trend.

  19. Classifying geometric variability by dominant eigenmodes of deformation in regressing tumours during active breath hold lung cancer radiotherapy

    PubMed Central

    Badawi, Ahmed M.; Weiss, Elisabeth; Sleeman, William C.

    2012-01-01

    The purpose of this study is to develop and evaluate a lung tumour interfraction geometric variability classification scheme as a means to guide adaptive radiotherapy and improve measurement of treatment response. Principal component analysis (PCA) was used to generate statistical shape models of the gross tumour volume (GTV) for 12 patients with weekly breath hold CT scans. Each eigenmode of the PCA model was classified as ‘trending’ or ‘non-trending’ depending on whether its contribution to the overall GTV variability included a time trend over the treatment course. Trending eigenmodes were used to reconstruct the original semi-automatically delineated GTVs into a reduced model containing only time trends. Reduced models were compared to the original GTVs by analyzing reconstruction error in the GTV volume and position. Both retrospective (all weekly images) and prospective (only the first four weekly images) were evaluated. Average volume difference from the original GTV was 4.3% ± 2.4% for the trending model. The positional variability of the GTV over the treatment course, as measured by the standard deviation of the GTV centroid, was 1.9 ± 1.4 mm for the original GTVs, which was reduced to 1.2 ± 0.6 mm for the trending only model. In 3/13 cases the dominant eigenmode changed class between the prospective and retrospective models. The trending only model preserved GTV volume and shape relative to the original GTVs, while reducing spurious positional variability. The classification scheme appears feasible for separating types of geometric variability by time trend. PMID:22172998

  20. Bad Breath

    MedlinePlus

    ... habits, like brushing and flossing regularly, help fight bad breath. Mouthwashes, mints or chewing gum may make your breath fresher. If you have an underlying disorder, treating it may help eliminate the breath odor.

  1. The Association between Neuroticism and Heart Rate Variability Is Not Fully Explained by Cardiovascular Disease and Depression

    PubMed Central

    Čukić, Iva; Bates, Timothy C.

    2015-01-01

    Neuroticism is associated with cardiovascular disease, autonomic reactivity, and depression. Here we address the extent to which neuroticism accounts for the excess heart disease risk associated with depression and test whether cardiac autonomic tone plays a role as mediator. Subjects were derived from a nationally representative sample (n = 1,255: mean age 54.5, SD = 11.5). Higher neuroticism was associated with reduced heart rate variability equally under rest and stress. The baseline structural equation model revealed significant paths from neuroticism to heart rate variability, cardiovascular disease and depression, and between depression and cardiovascular disease, controlling for age, sex, height, weight, and BMI. Dropping both the neuroticism to heart rate variability, and neuroticism to heart disease paths significantly reduced the model fit (p < .001 in each case). We conclude that neuroticism has independent associations with both autonomic reactivity and cardiovascular disease, over and above its associations with depression and other related variables. PMID:25951236

  2. On the nature of heart rate variability in a breathing normal subject: A stochastic process analysis

    NASA Astrophysics Data System (ADS)

    Buchner, Teodor; Petelczyc, Monika; Żebrowski, Jan J.; Prejbisz, Aleksander; Kabat, Marek; Januszewicz, Andrzej; Piotrowska, Anna Justyna; Szelenberger, Waldemar

    2009-06-01

    Human heart rate is moderated by the autonomous nervous system acting predominantly through the sinus node (the main cardiac physiological pacemaker). One of the dominant factors that determine the heart rate in physiological conditions is its coupling with the respiratory rhythm. Using the language of stochastic processes, we analyzed both rhythms simultaneously taking the data from polysomnographic recordings of two healthy individuals. Each rhythm was treated as a sum of a deterministic drift term and a diffusion term (Kramers-Moyal expansion). We found that normal heart rate variability may be considered as the result of a bidirectional coupling of two nonlinear oscillators: the heart itself and the respiratory system. On average, the diffusion (noise) component measured is comparable in magnitude to the oscillatory (deterministic) term for both signals investigated. The application of the Kramers-Moyal expansion may be useful for medical diagnostics providing information on the relation between respiration and heart rate variability. This interaction is mediated by the autonomous nervous system, including the baroreflex, and results in a commonly observed phenomenon—respiratory sinus arrhythmia which is typical for normal subjects and often impaired by pathology.

  3. The Applicability of Nonlinear Systems Dynamics Chaos Measures to Cardiovascular Physiology Variables

    NASA Technical Reports Server (NTRS)

    Hooker, John C.

    1991-01-01

    Three measures of nonlinear chaos (fractal dimension, Approximate Entropy (ApEn), and Lyapunov exponents) were studied as potential measures of cardiovascular condition. It is suggested that these measures have potential in the assessment of cardiovascular condition in environments of normal cardiovascular stress (normal gravity on the Earth surface), cardiovascular deconditioning (microgravity of space), and increased cardiovascular stress (lower body negative pressure (LBNP) treatments).

  4. Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children

    PubMed Central

    Szmuchrowski, LA; Prado, LS; Couto, BP; Machado, JCQ; Damasceno, VO; Lamounier, JA

    2014-01-01

    The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. PMID:26424930

  5. Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children.

    PubMed

    Gonçalves, R; Szmuchrowski, L A; Prado, L S; Couto, B P; Machado, Jcq; Damasceno, V O; Lamounier, J A

    2015-09-01

    The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. PMID:26424930

  6. Is breathing rate a confounding variable in brain-computer interfaces (BCIs) based on EEG spectral power?

    PubMed

    Ibarra Chaoul, Andrea; Grosse-Wentrup, Moritz

    2015-08-01

    Brain-computer interfaces (BCIs) enable paralyzed patients to interact with the world by directly decoding brain activity. We investigated if systematic changes in breathing rate affect EEG bandpower features that are commonly used in BCIs. This is of particular interest for the development of cognitive BCIs for patients with artificial ventilation, e.g. for those in late stages of amyotrophic lateral sclerosis (ALS). If subjects can alter the spectrum of the EEG by changing their breathing rate, decoding results obtained with healthy subjects may not generalize to this patient population. We recorded a high-density EEG from twelve healthy subjects, who were instructed to alternate between fast and slow breathing. We do not find any statistically significant modulation of EEG bandpower. As such, changes in breathing rate are unlikely to substantially bias the performance of BCIs based on EEG bandpower features.

  7. Slow Breathing and Hypoxic Challenge: Cardiorespiratory Consequences and Their Central Neural Substrates

    PubMed Central

    Critchley, Hugo D.; Nicotra, Alessia; Chiesa, Patrizia A.; Nagai, Yoko; Gray, Marcus A.; Minati, Ludovico; Bernardi, Luciano

    2015-01-01

    Controlled slow breathing (at 6/min, a rate frequently adopted during yoga practice) can benefit cardiovascular function, including responses to hypoxia. We tested the neural substrates of cardiorespiratory control in humans during volitional controlled breathing and hypoxic challenge using functional magnetic resonance imaging (fMRI). Twenty healthy volunteers were scanned during paced (slow and normal rate) breathing and during spontaneous breathing of normoxic and hypoxic (13% inspired O2) air. Cardiovascular and respiratory measures were acquired concurrently, including beat-to-beat blood pressure from a subset of participants (N = 7). Slow breathing was associated with increased tidal ventilatory volume. Induced hypoxia raised heart rate and suppressed heart rate variability. Within the brain, slow breathing activated dorsal pons, periaqueductal grey matter, cerebellum, hypothalamus, thalamus and lateral and anterior insular cortices. Blocks of hypoxia activated mid pons, bilateral amygdalae, anterior insular and occipitotemporal cortices. Interaction between slow breathing and hypoxia was expressed in ventral striatal and frontal polar activity. Across conditions, within brainstem, dorsal medullary and pontine activity correlated with tidal volume and inversely with heart rate. Activity in rostroventral medulla correlated with beat-to-beat blood pressure and heart rate variability. Widespread insula and striatal activity tracked decreases in heart rate, while subregions of insular cortex correlated with momentary increases in tidal volume. Our findings define slow breathing effects on central and cardiovascular responses to hypoxic challenge. They highlight the recruitment of discrete brainstem nuclei to cardiorespiratory control, and the engagement of corticostriatal circuitry in support of physiological responses that accompany breathing regulation during hypoxic challenge. PMID:25973923

  8. Breathing Problems

    MedlinePlus

    ... re not getting enough air. Sometimes mild breathing problems are from a stuffy nose or hard exercise. ... emphysema or pneumonia cause breathing difficulties. So can problems with your trachea or bronchi, which are part ...

  9. Physiological variability in volatile organic compounds (VOCs) in exhaled breath and released from faeces due to nutrition and somatic growth in a standardized caprine animal model.

    PubMed

    Fischer, Sina; Trefz, Phillip; Bergmann, Andreas; Steffens, Markus; Ziller, Mario; Miekisch, Wolfram; Schubert, Jochen S; Köhler, Heike; Reinhold, Petra

    2015-06-01

    Physiological effects may change volatile organic compound (VOC) concentrations and may therefore act as confounding factors in the definition of VOCs as disease biomarkers. To evaluate the extent of physiological background variability, this study assessed the effects of feed composition and somatic growth on VOC patterns in a standardized large animal model. Fifteen clinically healthy goats were followed during their first year of life. VOCs present in the headspace over faeces, exhaled breath and ambient air inside the stable were repeatedly assessed in parallel with the concentrations of glucose, protein, and albumin in venous blood. VOCs were collected and analysed using solid-phase or needle-trap microextraction and gas chromatograpy together with mass spectroscopy. The concentrations of VOCs in exhaled breath and above faeces varied significantly with increasing age of the animals. The largest variations in volatiles detected in the headspace over faeces occurred with the change from milk feeding to plant-based diet. VOCs above faeces and in exhaled breath correlated significantly with blood components. Among VOCs exhaled, the strongest correlations were found between exhaled nonanal concentrations and blood concentrations of glucose and albumin. Results stress the importance of a profound knowledge of the physiological backgrounds of VOC composition before defining reliable and accurate marker sets for diagnostic purposes. PMID:25971714

  10. Decreased reaction time variability is associated with greater cardiovascular responses to acute stress.

    PubMed

    Wawrzyniak, Andrew J; Hamer, Mark; Steptoe, Andrew; Endrighi, Romano

    2016-05-01

    Cardiovascular (CV) responses to mental stress are prospectively associated with poor CV outcomes. The association between CV responses to mental stress and reaction times (RTs) in aging individuals may be important but warrants further investigation. The present study assessed RTs to examine associations with CV responses to mental stress in healthy, older individuals using robust regression techniques. Participants were 262 men and women (mean age = 63.3 ± 5.5 years) from the Whitehall II cohort who completed a RT task (Stroop) and underwent acute mental stress (mirror tracing) to elicit CV responses. Blood pressure, heart rate, and heart rate variability were measured at baseline, during acute stress, and through a 75-min recovery. RT measures were generated from an ex-Gaussian distribution that yielded three predictors: mu-RT, sigma-RT, and tau-RT, the mean, standard deviation, and mean of the exponential component of the normal distribution, respectively. Decreased intraindividual RT variability was marginally associated with greater systolic (B = -.009, SE = .005, p = .09) and diastolic (B = -.004, SE = .002, p = .08) blood pressure reactivity. Decreased intraindividual RT variability was associated with impaired systolic blood pressure recovery (B = -.007, SE = .003, p = .03) and impaired vagal tone (B = -.0047, SE = .0024, p = .045). Study findings offer tentative support for an association between RTs and CV responses. Despite small effect sizes and associations not consistent across predictors, these data may point to a link between intrinsic neuronal plasticity and CV responses. PMID:26894967

  11. Decreased reaction time variability is associated with greater cardiovascular responses to acute stress

    PubMed Central

    Hamer, Mark; Steptoe, Andrew; Endrighi, Romano

    2016-01-01

    Abstract Cardiovascular (CV) responses to mental stress are prospectively associated with poor CV outcomes. The association between CV responses to mental stress and reaction times (RTs) in aging individuals may be important but warrants further investigation. The present study assessed RTs to examine associations with CV responses to mental stress in healthy, older individuals using robust regression techniques. Participants were 262 men and women (mean age = 63.3 ± 5.5 years) from the Whitehall II cohort who completed a RT task (Stroop) and underwent acute mental stress (mirror tracing) to elicit CV responses. Blood pressure, heart rate, and heart rate variability were measured at baseline, during acute stress, and through a 75‐min recovery. RT measures were generated from an ex‐Gaussian distribution that yielded three predictors: mu‐RT, sigma‐RT, and tau‐RT, the mean, standard deviation, and mean of the exponential component of the normal distribution, respectively. Decreased intraindividual RT variability was marginally associated with greater systolic (B = −.009, SE = .005, p = .09) and diastolic (B = −.004, SE = .002, p = .08) blood pressure reactivity. Decreased intraindividual RT variability was associated with impaired systolic blood pressure recovery (B = −.007, SE = .003, p = .03) and impaired vagal tone (B = −.0047, SE = .0024, p = .045). Study findings offer tentative support for an association between RTs and CV responses. Despite small effect sizes and associations not consistent across predictors, these data may point to a link between intrinsic neuronal plasticity and CV responses. PMID:26894967

  12. Decreased reaction time variability is associated with greater cardiovascular responses to acute stress.

    PubMed

    Wawrzyniak, Andrew J; Hamer, Mark; Steptoe, Andrew; Endrighi, Romano

    2016-05-01

    Cardiovascular (CV) responses to mental stress are prospectively associated with poor CV outcomes. The association between CV responses to mental stress and reaction times (RTs) in aging individuals may be important but warrants further investigation. The present study assessed RTs to examine associations with CV responses to mental stress in healthy, older individuals using robust regression techniques. Participants were 262 men and women (mean age = 63.3 ± 5.5 years) from the Whitehall II cohort who completed a RT task (Stroop) and underwent acute mental stress (mirror tracing) to elicit CV responses. Blood pressure, heart rate, and heart rate variability were measured at baseline, during acute stress, and through a 75-min recovery. RT measures were generated from an ex-Gaussian distribution that yielded three predictors: mu-RT, sigma-RT, and tau-RT, the mean, standard deviation, and mean of the exponential component of the normal distribution, respectively. Decreased intraindividual RT variability was marginally associated with greater systolic (B = -.009, SE = .005, p = .09) and diastolic (B = -.004, SE = .002, p = .08) blood pressure reactivity. Decreased intraindividual RT variability was associated with impaired systolic blood pressure recovery (B = -.007, SE = .003, p = .03) and impaired vagal tone (B = -.0047, SE = .0024, p = .045). Study findings offer tentative support for an association between RTs and CV responses. Despite small effect sizes and associations not consistent across predictors, these data may point to a link between intrinsic neuronal plasticity and CV responses.

  13. Cardiovascular disease risk factors and socioeconomic variables in a nation undergoing epidemiologic transition

    PubMed Central

    2013-01-01

    Background Cardiovascular disease (CVD) related deaths is not only the prime cause of mortality in the world, it has also continued to increase in the low and middle income countries. Hence, this study examines the relationship between CVD risk factors and socioeconomic variables in Malaysia, which is a rapidly growing middle income nation undergoing epidemiologic transition. Methods Using data from 11,959 adults aged 30 years and above, and living in urban and rural areas between 2007 and 2010, this study attempts to examine the prevalence of CVD risk factors, and the association between these factors, and socioeconomic and demographic variables in Malaysia. The socioeconomic and demographic, and anthropometric data was obtained with blood pressure and fasting venous blood for glucose and lipids through a community-based survey. Results The association between CVD risk factors, and education and income was mixed. There was a negative association between smoking and hypertension, and education and income. The association between diabetes, hypercholesterolemia and being overweight with education and income was not clear. More men than women smoked in all education and income groups. The remaining consistent results show that the relationship between smoking, and education and income was obvious and inverse among Malays, others, rural women, Western Peninsular Malaysia (WPM) and Eastern Peninsular Malaysia (EPM). Urban men showed higher prevalence of being overweight than rural men in all education and income categories. Except for those with no education more rural men smoked than urban men. Also, Malay men in all education and income categories showed the highest prevalence of smoking among the ethnic groups. Conclusions The association between CVD risk factors and socioeconomic variables should be considered when formulating programmes to reduce morbidity and mortality rates in low and middle income countries. While general awareness programmes should be targeted

  14. Regional variability in diving physiology and behavior in a widely distributed air-breathing marine predator, the South American sea lion (Otaria byronia).

    PubMed

    Hückstädt, Luis A; Tift, Michael S; Riet-Sapriza, Federico; Franco-Trecu, Valentina; Baylis, Alastair M M; Orben, Rachael A; Arnould, John P Y; Sepulveda, Maritza; Santos-Carvallo, Macarena; Burns, Jennifer M; Costa, Daniel P

    2016-08-01

    Our understanding of how air-breathing marine predators cope with environmental variability is limited by our inadequate knowledge of their ecological and physiological parameters. Because of their wide distribution along both coasts of the sub-continent, South American sea lions (Otaria byronia) provide a valuable opportunity to study the behavioral and physiological plasticity of a marine predator in different environments. We measured the oxygen stores and diving behavior of South American sea lions throughout most of its range, allowing us to demonstrate that diving ability and behavior vary across its range. We found no significant differences in mass-specific blood volumes of sea lions among field sites and a negative relationship between mass-specific oxygen storage and size, which suggests that exposure to different habitats and geographical locations better explains oxygen storage capacities and diving capability in South American sea lions than body size alone. The largest animals in our study (individuals from Uruguay) were the shallowest and shortest duration divers, and had the lowest mass-specific total body oxygen stores, while the deepest and longest duration divers (individuals from southern Chile) had significantly larger mass-specific oxygen stores, despite being much smaller animals. Our study suggests that the physiology of air-breathing diving predators is not fixed, but that it can be adjusted, to a certain extent, depending on the ecological setting and or habitat. These adjustments can be thought of as a 'training effect': as the animal continues to push its physiological capacity through greater hypoxic exposure, its breath-holding capacity increases.

  15. Regional variability in diving physiology and behavior in a widely distributed air-breathing marine predator, the South American sea lion (Otaria byronia).

    PubMed

    Hückstädt, Luis A; Tift, Michael S; Riet-Sapriza, Federico; Franco-Trecu, Valentina; Baylis, Alastair M M; Orben, Rachael A; Arnould, John P Y; Sepulveda, Maritza; Santos-Carvallo, Macarena; Burns, Jennifer M; Costa, Daniel P

    2016-08-01

    Our understanding of how air-breathing marine predators cope with environmental variability is limited by our inadequate knowledge of their ecological and physiological parameters. Because of their wide distribution along both coasts of the sub-continent, South American sea lions (Otaria byronia) provide a valuable opportunity to study the behavioral and physiological plasticity of a marine predator in different environments. We measured the oxygen stores and diving behavior of South American sea lions throughout most of its range, allowing us to demonstrate that diving ability and behavior vary across its range. We found no significant differences in mass-specific blood volumes of sea lions among field sites and a negative relationship between mass-specific oxygen storage and size, which suggests that exposure to different habitats and geographical locations better explains oxygen storage capacities and diving capability in South American sea lions than body size alone. The largest animals in our study (individuals from Uruguay) were the shallowest and shortest duration divers, and had the lowest mass-specific total body oxygen stores, while the deepest and longest duration divers (individuals from southern Chile) had significantly larger mass-specific oxygen stores, despite being much smaller animals. Our study suggests that the physiology of air-breathing diving predators is not fixed, but that it can be adjusted, to a certain extent, depending on the ecological setting and or habitat. These adjustments can be thought of as a 'training effect': as the animal continues to push its physiological capacity through greater hypoxic exposure, its breath-holding capacity increases. PMID:27247316

  16. Bad Breath

    MedlinePlus

    ... hygiene leads to bad breath because when food particles are left in your mouth, they can rot ... Flossing once a day helps get rid of particles wedged between your teeth. Also, visit your dentist ...

  17. Comparison of cardiorespiratory variables in dorsally recumbent horses anesthetized with guaifenesin-ketamine-xylazine spontaneously breathing 50% or maximal oxygen concentrations.

    PubMed

    Karrasch, Nicole M; Hubbell, John A E; Aarnes, Turi K; Bednarski, Richard M; Lerche, Phillip

    2015-04-01

    This study compared cardiorespiratory variables in dorsally recumbent horses anesthetized with guaifenesin-ketamine-xylazine and spontaneously breathing 50% or maximal (> 90%) oxygen (O2) concentrations. Twelve healthy mares were randomly assigned to breathe 50% or maximal O2 concentrations. Horses were sedated with xylazine, induced to recumbency with ketamine-diazepam, and anesthesia was maintained with guaifenesin-ketamine-xylazine to effect. Heart rate, arterial blood pressures, respiratory rate, lithium dilution cardiac output (CO), inspired and expired O2 and carbon dioxide partial pressures, and tidal volume were measured. Arterial and mixed-venous blood samples were collected prior to sedation (baseline), during 30 minutes of anesthesia, 10 minutes after disconnection from O2, and 30 minutes after standing. Shunt fraction, O2 delivery, and alveolar-arterial O2 partial pressures difference [P(A-a)O2] were calculated. Recovery times were recorded. There were no significant differences between groups in cardiorespiratory parameters or in P(A-a)O2 at baseline or 30 minutes after standing. Oxygen partial pressure difference in the 50% group was significantly less than in the maximal O2 group during anesthesia. PMID:25829559

  18. Comparison of cardiorespiratory variables in dorsally recumbent horses anesthetized with guaifenesin-ketamine-xylazine spontaneously breathing 50% or maximal oxygen concentrations

    PubMed Central

    Karrasch, Nicole M.; Hubbell, John A.E.; Aarnes, Turi K.; Bednarski, Richard M.; Lerche, Phillip

    2015-01-01

    This study compared cardiorespiratory variables in dorsally recumbent horses anesthetized with guaifenesin-ketamine-xylazine and spontaneously breathing 50% or maximal (> 90%) oxygen (O2) concentrations. Twelve healthy mares were randomly assigned to breathe 50% or maximal O2 concentrations. Horses were sedated with xylazine, induced to recumbency with ketamine-diazepam, and anesthesia was maintained with guaifenesin-ketamine-xylazine to effect. Heart rate, arterial blood pressures, respiratory rate, lithium dilution cardiac output (CO), inspired and expired O2 and carbon dioxide partial pressures, and tidal volume were measured. Arterial and mixed-venous blood samples were collected prior to sedation (baseline), during 30 minutes of anesthesia, 10 minutes after disconnection from O2, and 30 minutes after standing. Shunt fraction, O2 delivery, and alveolar-arterial O2 partial pressures difference [P(A-a)O2] were calculated. Recovery times were recorded. There were no significant differences between groups in cardiorespiratory parameters or in P(A-a)O2 at baseline or 30 minutes after standing. Oxygen partial pressure difference in the 50% group was significantly less than in the maximal O2 group during anesthesia. PMID:25829559

  19. Influence of Deep Breathing on Heart Rate Variability in Parkinson’s Disease: Co-relation with Severity of Disease and Non-Motor Symptom Scale Score

    PubMed Central

    Jagtap, Gayatri J; Chakor, Rahul T

    2014-01-01

    Context: Dysautonomia and non-motor symptoms (NMS) in Parkinson’s disease (PD) are frequent, disabling and reduce quality of life of patient. Aims and Objective: There is a paucity of studies on autonomic dysfunction in PD in Indian population. The study aimed to evaluate autonomic dysfunction in PD patients and co-relate the findings with severity of PD and Non-Motor Symptoms Scale (NMSS) score. Materials and Methods: We evaluated autonomic function in 30 diagnosed patients of PD (age 55-70 years) and 30 healthy age-matched controls by 3 min deep breathing test (DBT). NMSS was used to identify non-motor symptoms and Hoehn and Yahr (HY) Scale to grade severity of PD. The DBT findings were co-related with severity of PD (HY staging) and NMSS score. Results: DBT was found to be abnormal in 40% while it was on borderline in 33.3% of PD patients. There was a statistically significant difference (p<0.01) between patients and control group for the DBT. NMS were reported across all the stages of PD but with variable frequency and severity for individual symptom. A negative co-relation was found between results of deep breathing test and clinical severity of disease and NMSS score. Conclusion: Abnormalities of autonomic function and NMS were integral and present across all the stages of PD patients. Early recognition and treatment of these may decrease morbidity and improve quality of life of PD patients. PMID:25177554

  20. Breathing: Rhythmicity, Plasticity, Chemosensitivity

    PubMed Central

    Feldman, Jack L.; Mitchell, Gordon S.; Nattie, Eugene E.

    2010-01-01

    Breathing is a vital behavior that is particularly amenable to experimental investigation. We review recent progress on three problems of broad interest. (i) Where and how is respiratory rhythm generated? The preBötzinger Complex is a critical site, whereas pacemaker neurons may not be essential. The possibility that coupled oscillators are involved is considered. (ii) What are the mechanisms that underlie the plasticity necessary for adaptive changes in breathing? Serotonin-dependent long-term facilitation following intermittent hypoxia is an important example of such plasticity, and a model that can account for this adaptive behavior is discussed. (iii) Where and how are the regulated variables CO2 and pH sensed? These sensors are essential if breathing is to be appropriate for metabolism. Neurons with appropriate chemosensitivity are spread throughout the brainstem; their individual properties and collective role are just beginning to be understood. PMID:12598679

  1. How to breathe when you are short of breath

    MedlinePlus

    Pursed lip breathing; COPD - pursed lip breathing; Emphysema - pursed lip breathing; Chronic bronchitis - pursed lip breathing; Pulmonary fibrosis - pursed lip breathing; Interstitial lung disease - pursed lip breathing; Hypoxia - pursed lip breathing; ...

  2. Cardiovascular Response Identification Based on Nonlinear Support Vector Regression

    NASA Astrophysics Data System (ADS)

    Wang, Lu; Su, Steven W.; Chan, Gregory S. H.; Celler, Branko G.; Cheng, Teddy M.; Savkin, Andrey V.

    This study experimentally investigates the relationships between central cardiovascular variables and oxygen uptake based on nonlinear analysis and modeling. Ten healthy subjects were studied using cycle-ergometry exercise tests with constant workloads ranging from 25 Watt to 125 Watt. Breath by breath gas exchange, heart rate, cardiac output, stroke volume and blood pressure were measured at each stage. The modeling results proved that the nonlinear modeling method (Support Vector Regression) outperforms traditional regression method (reducing Estimation Error between 59% and 80%, reducing Testing Error between 53% and 72%) and is the ideal approach in the modeling of physiological data, especially with small training data set.

  3. Inhibition of hydrogen sulfide restores normal breathing stability and improves autonomic control during experimental heart failure

    PubMed Central

    Del Rio, Rodrigo; Marcus, Noah J.

    2013-01-01

    Cardiovascular autonomic imbalance and breathing instability are major contributors to the progression of heart failure (CHF). Potentiation of the carotid body (CB) chemoreflex has been shown to contribute to these effects. Hydrogen sulfide (H2S) recently has been proposed to mediate CB hypoxic chemoreception. We hypothesized that H2S synthesis inhibition should decrease CB chemoreflex activation and improve breathing stability and autonomic function in CHF rats. Using the irreversible inhibitor of cystathione γ-lyase dl-propargylglycine (PAG), we tested the effects of H2S inhibition on resting breathing patterns, the hypoxic and hypercapnic ventilatory responses, and the hypoxic sensitivity of CB chemoreceptor afferents in rats with CHF. In addition, heart rate variability (HRV) and systolic blood pressure variability (SBPV) were calculated as an index of autonomic function. CHF rats, compared with sham rats, exhibited increased breath interval variability and number of apneas, enhanced CB afferent discharge and ventilatory responses to hypoxia, decreased HRV, and increased low-frequency SBPV. Remarkably, PAG treatment reduced the apnea index by 90%, reduced breath interval variability by 40–60%, and reversed the enhanced hypoxic CB afferent and chemoreflex responses observed in CHF rats. Furthermore, PAG treatment partially reversed the alterations in HRV and SBPV in CHF rats. Our results show that PAG treatment restores breathing stability and cardiac autonomic function and reduces the enhanced ventilatory and CB chemosensory responses to hypoxia in CHF rats. These results support the idea that PAG treatment could potentially represent a novel pathway to control sympathetic outflow and breathing instability in CHF. PMID:23449938

  4. Can arterial wave augmentation in young adults help account for variability of cardiovascular risk in different British ethnic groups?

    PubMed Central

    Faconti, Luca; Silva, Maria J.; Molaodi, Oarabile R.; Enayat, Zinat E.; Cassidy, Aidan; Karamanos, Alexis; Nanino, Elisa; Read, Ursula M.; Dall, Philippa; Stansfield, Ben; Harding, Seeromanie; Cruickshank, Kennedy J.

    2016-01-01

    Objective: Traditional cardiovascular risk factors do not fully account for ethnic differences in cardiovascular disease. We tested if arterial function indices, particularly augmentation index (AIx), and their determinants from childhood could underlie such ethnic variability among young British adults in the ‘DASH’ longitudinal study. Methods: DASH, at http://dash.sphsu.mrc.ac.uk/, includes representative samples of six main British ethnic groups. Pulse wave velocity (PWV) and AIx were recorded using the Arteriograph device at ages 21–23 years in a subsample (n = 666); psychosocial, anthropometric, and blood pressure (BP) measures were collected then and in two previous surveys at ages 11–13 years and 14–16 years. For n = 334, physical activity was measured over 5 days (ActivPal). Results: Unadjusted values and regression models for PWVs were similar or lower in ethnic minority than in White UK young adults, whereas AIx was higher – Caribbean (14.9, 95% confidence interval 12.3–17.0%), West African (15.3, 12.9–17.7%), Indian (15.1, 13.0–17.2%), and Pakistani/Bangladeshi (15.7, 13.7–17.7%), compared with White UK (11.9, 10.2–13.6%). In multivariate models, adjusted for sex, central SBP, height, and heart rate, Indian and Pakistani/Bangladeshi young adults had higher AIx (β = 3.35, 4.20, respectively, P < 0.01) than White UK with a similar trend for West Africans and Caribbeans but not statistically significant. Unlike PWV, physical activity, psychosocial or deprivation measures were not associated with AIx, with borderline associations from brachial BP but no other childhood variables. Conclusion: Early adult AIx, but not arterial stiffness, may be a useful tool for testing components of excess cardiovascular risk in some ethnic minority groups. PMID:27490950

  5. The association between phenomena on the Sun, geomagnetic activity, meteorological variables, and cardiovascular characteristic of patients with myocardial infarction

    NASA Astrophysics Data System (ADS)

    Vencloviene, Jone; Babarskiene, Ruta; Slapikas, Rimvydas; Sakalyte, Gintare

    2013-09-01

    It has been found that solar and geomagnetic activity affects the cardiovascular system. Some evidence has been reported on the increase in the rate of myocardial infarction, stroke and myocardial infarction related deaths during geomagnetic storms. We investigated the association between cardiovascular characteristics of patients, admitted for myocardial infarction with ST elevation (STEMI), and geomagnetic activity (GMA), solar proton events (SPE), solar flares, and meteorological variables during admission. The data of 1,979 patients hospitalized at the Hospital of Lithuanian University of Health Sciences (Kaunas) were analyzed. We evaluated the association between environmental variables and patient's characteristics by multivariate logistic regression, controlling patient's gender and age. Two days after geomagnetic storms the risk of STEMI was over 1.5 times increased in patients who had a medical history of myocardial infarction, stable angina, renal or pulmonary diseases. The dose-response association between GMA level and STEMI risk for patients with renal diseases in history was observed. Two days after SPE the risk of STEMI in patients with stable angina in anamnesis was increased over 1.5 times, adjusting by GMA level. The SPE were associated with an increase of risk for patients with renal diseases in history. This study confirms the strongest effect of phenomena in the Sun in high risk patients.

  6. The association between phenomena on the sun, geomagnetic activity, meteorological variables, and cardiovascular characteristic of patients with myocardial infarction.

    PubMed

    Vencloviene, Jone; Babarskiene, Ruta; Slapikas, Rimvydas; Sakalyte, Gintare

    2013-09-01

    It has been found that solar and geomagnetic activity affects the cardiovascular system. Some evidence has been reported on the increase in the rate of myocardial infarction, stroke and myocardial infarction related deaths during geomagnetic storms. We investigated the association between cardiovascular characteristics of patients, admitted for myocardial infarction with ST elevation (STEMI), and geomagnetic activity (GMA), solar proton events (SPE), solar flares, and meteorological variables during admission. The data of 1,979 patients hospitalized at the Hospital of Lithuanian University of Health Sciences (Kaunas) were analyzed. We evaluated the association between environmental variables and patient's characteristics by multivariate logistic regression, controlling patient's gender and age. Two days after geomagnetic storms the risk of STEMI was over 1.5 times increased in patients who had a medical history of myocardial infarction, stable angina, renal or pulmonary diseases. The dose-response association between GMA level and STEMI risk for patients with renal diseases in history was observed. Two days after SPE the risk of STEMI in patients with stable angina in anamnesis was increased over 1.5 times, adjusting by GMA level. The SPE were associated with an increase of risk for patients with renal diseases in history. This study confirms the strongest effect of phenomena in the Sun in high risk patients.

  7. The association between phenomena on the sun, geomagnetic activity, meteorological variables, and cardiovascular characteristic of patients with myocardial infarction.

    PubMed

    Vencloviene, Jone; Babarskiene, Ruta; Slapikas, Rimvydas; Sakalyte, Gintare

    2013-09-01

    It has been found that solar and geomagnetic activity affects the cardiovascular system. Some evidence has been reported on the increase in the rate of myocardial infarction, stroke and myocardial infarction related deaths during geomagnetic storms. We investigated the association between cardiovascular characteristics of patients, admitted for myocardial infarction with ST elevation (STEMI), and geomagnetic activity (GMA), solar proton events (SPE), solar flares, and meteorological variables during admission. The data of 1,979 patients hospitalized at the Hospital of Lithuanian University of Health Sciences (Kaunas) were analyzed. We evaluated the association between environmental variables and patient's characteristics by multivariate logistic regression, controlling patient's gender and age. Two days after geomagnetic storms the risk of STEMI was over 1.5 times increased in patients who had a medical history of myocardial infarction, stable angina, renal or pulmonary diseases. The dose-response association between GMA level and STEMI risk for patients with renal diseases in history was observed. Two days after SPE the risk of STEMI in patients with stable angina in anamnesis was increased over 1.5 times, adjusting by GMA level. The SPE were associated with an increase of risk for patients with renal diseases in history. This study confirms the strongest effect of phenomena in the Sun in high risk patients. PMID:23179321

  8. Cardiovascular Risk Evaluation through Heart Rate Variability (HRV) Analysis in Patients with Psoriasis before and after 12 Weeks of Etanercept Therapy: A Preliminary Prospective Study.

    PubMed

    Potenza, Concetta; Raimondi, Gianfranco; Pampena, Riccardo; Bernardini, Nicoletta; La Viola, Giorgio; Tolino, Ersilia; Zuber, Sara; Scordamaglia, Beatrice; Skroza, Nevena

    2016-08-01

    The association between psoriasis and cardiovascular diseases has been indicated by epidemiological studies. The sub-inflammatory systemic state that characterizes both psoriasis and atherosclerosis has been proposed as the link between these conditions; it cannot, however, explain the increased incidence of sudden cardiac death reported in young patients with severe psoriasis without common cardiovascular risk factors. In a previous study, we reported higher levels of autonomic dysregulation in patients with psoriasis, concluding that the prevalence of the sympathetic arm over the parasympathetic could increase cardiovascular risk. Objective of this study was to assess the influence of etanercept on autonomic cardiovascular regulation in young patients with moderate-to-severe psoriasis without cardiovascular risk factors. Five-minute ECG recordings were collected at rest before and after 12 weeks of therapy with etanercept in 19 young patients with psoriasis without cardiovascular risk factors. The Cardiolab CE pocket PC ECG system was used for linear methods of heart rate variability (HRV) analysis. No significant change in HRV analysis parameters was apparent after 12 weeks of etanercept therapy. Our data suggest that treatment with etanercept in patients with moderate-to-severe psoriasis does not affect cardiovascular autonomic regulation and cardiovascular risk. PMID:27663918

  9. Prediction of space sickness in astronauts from preflight fluid, electrolyte, and cardiovascular variables and Weightless Environmental Training Facility (WETF) training

    NASA Technical Reports Server (NTRS)

    Simanonok, K.; Mosely, E.; Charles, J.

    1992-01-01

    Nine preflight variables related to fluid, electrolyte, and cardiovascular status from 64 first-time Shuttle crewmembers were differentially weighted by discrimination analysis to predict the incidence and severity of each crewmember's space sickness as rated by NASA flight surgeons. The nine variables are serum uric acid, red cell count, environmental temperature at the launch site, serum phosphate, urine osmolality, serum thyroxine, sitting systolic blood pressure, calculated blood volume, and serum chloride. Using two methods of cross-validation on the original samples (jackknife and a stratefied random subsample), these variables enable the prediction of space sickness incidence (NONE or SICK) with 80 percent sickness and space severity (NONE, MILD, MODERATE, of SEVERE) with 59 percent success by one method of cross-validation and 67 percent by another method. Addition of a tenth variable, hours spent in the Weightlessness Environment Training Facility (WETF) did not improve the prediction of space sickness incidences but did improve the prediction of space sickness severity to 66 percent success by the first method of cross-validation of original samples and to 71 percent by the second method. Results to date suggest the presence of predisposing physiologic factors to space sickness that implicate fluid shift etiology. The data also suggest that prior exposure to fluid shift during WETF training may produce some circulatory pre-adaption to fluid shifts in weightlessness that results in a reduction of space sickness severity.

  10. Cross-spectral coherence between geomagnetic disturbance and human cardiovascular variables at non-societal frequencies.

    PubMed

    Watanabe, Y; Hillman, D C; Otsuka, K; Bingham, C; Breus, T K; Cornélissen, G; Halberg, F

    1994-01-01

    A 35-year-old cardiologist monitored himself with an automatic ABPM-630 (Colin Electronics) monitor, mostly at 15-minute intervals around-the-clock for three years with a few interruptions. In this subject with a family history of high blood pressure and stroke, a cross-spectral analysis revealed a statistically significant coherence at 27.7 days between systolic and diastolic blood pressure and heart rate vs. the geomagnetic disturbance index, Kp. A lesser peak in coherence was found for systolic blood pressure with Kp at a trial period of 4.16 days (P = 0.046). These results suggest that changes in geomagnetism may influence the human circulation, at least in the presence of familial cardiovascular disease risk, and they may do so at frequencies that have no precise human-made cyclic worldwide match. PMID:7729242

  11. Algorithms for the inference of causality in dynamic processes: Application to cardiovascular and cerebrovascular variability.

    PubMed

    Faes, Luca; Porta, Alberto; Nollo, Giandomenico

    2015-08-01

    This study faces the problem of causal inference in multivariate dynamic processes, with specific regard to the detection of instantaneous and time-lagged directed interactions. We point out the limitations of the traditional Granger causality analysis, showing that it leads to false detection of causality when instantaneous and time-lagged effects coexist in the process structure. Then, we propose an improved algorithm for causal inference that combines the Granger framework with the approach proposed by Pearl for the study of causality among multiple random variables. This new approach is compared with the traditional one in theoretical and simulated examples of interacting processes, showing its ability to retrieve the correct structure of instantaneous and time-lagged interactions. These approaches for causal inference are then tested on the physiological variability series of heart period, arterial pressure and cerebral blood flow variability obtained in subjects with postural-related syncope during a tilt-test protocol.

  12. Kidney motion during free breathing and breath hold for MR-guided radiotherapy

    NASA Astrophysics Data System (ADS)

    Stam, Mette K.; van Vulpen, Marco; Barendrecht, Maurits M.; Zonnenberg, Bernard A.; Intven, Martijn; Crijns, Sjoerd P. M.; Lagendijk, Jan J. W.; Raaymakers, Bas W.

    2013-04-01

    Current treatments for renal cell carcinoma have a high complication rate due to the invasiveness of the treatment. With the MRI-linac it may be possible to treat renal tumours non-invasively with high-precision radiotherapy. This is expected to reduce complications. To deliver a static dose distribution, radiation gating will be used. In this study the reproducibility and efficiency of free breathing gating and a breath hold treatment of the kidney was investigated. For 15 patients with a renal lesion the kidney motion during 2 min of free breathing and 10 consecutive expiration breath holds was studied with 2D cine MRI. The variability in kidney expiration position and treatment efficiency for gating windows of 1 to 20 mm was measured for both breathing patterns. Additionally the time trend in free breathing and the variation in expiration breath hold kidney position with baseline shift correction was determined. In 80% of the patients the variation in expiration position during free breathing is smaller than 2 mm. No clinically relevant time trends were detected. The variation in expiration breath hold is for all patients larger than the free breathing expiration variation. Gating on free breathing is, for gating windows of 1 to 5 mm more efficient than breath hold without baseline correction. When applying a baseline correction to the breath hold it increases the treatment efficiency. The kidney position is more reproducible in expiration free breathing than non-guided expiration breath hold. For small gating windows it is also more time efficient. Since free breathing also seems more comfortable for the patients it is the preferred breathing pattern for MRI-Linac treatments of the kidney.

  13. What Controls Your Breathing?

    MedlinePlus

    ... To a limited degree, you can change your breathing rate, such as by breathing faster or holding your ... oxygen levels in your blood and change your breathing rate as needed. Sensors in the airways detect lung ...

  14. Breath alcohol test

    MedlinePlus

    Alcohol test - breath ... There are various brands of breath alcohol tests. Each one uses a different method to test the level of alcohol in the breath. The machine may be electronic or manual. One ...

  15. Breath-Holding Spells

    MedlinePlus

    ... less than a minute before a child regains consciousness and resumes breathing normally. Breath-holding spells can ... spells cause kids to stop breathing and lose consciousness for up to a minute. In the most ...

  16. Oscillatory patterns in sympathetic neural discharge and cardiovascular variables during orthostatic stimulus

    NASA Technical Reports Server (NTRS)

    Furlan, R.; Porta, A.; Costa, F.; Tank, J.; Baker, L.; Schiavi, R.; Robertson, D.; Malliani, A.; Mosqueda-Garcia, R.

    2000-01-01

    BACKGROUND: We tested the hypothesis that a common oscillatory pattern might characterize the rhythmic discharge of muscle sympathetic nerve activity (MSNA) and the spontaneous variability of heart rate and systolic arterial pressure (SAP) during a physiological increase of sympathetic activity induced by the head-up tilt maneuver. METHODS AND RESULTS: Ten healthy subjects underwent continuous recordings of ECG, intra-arterial pressure, respiratory activity, central venous pressure, and MSNA, both in the recumbent position and during 75 degrees head-up tilt. Venous samplings for catecholamine assessment were obtained at rest and during the fifth minute of tilt. Spectrum and cross-spectrum analyses of R-R interval, SAP, and MSNA variabilities and of respiratory activity provided the low (LF, 0.1 Hz) and high frequency (HF, 0.27 Hz) rhythmic components of each signal and assessed their linear relationships. Compared with the recumbent position, tilt reduced central venous pressure, but blood pressure was unchanged. Heart rate, MSNA, and plasma epinephrine and norepinephrine levels increased, suggesting a marked enhancement of overall sympathetic activity. During tilt, LF(MSNA) increased compared with the level in the supine position; this mirrored similar changes observed in the LF components of R-R interval and SAP variabilities. The increase of LF(MSNA) was proportional to the amount of the sympathetic discharge. The coupling between LF components of MSNA and R-R interval and SAP variabilities was enhanced during tilt compared with rest. CONCLUSIONS: During the sympathetic activation induced by tilt, a similar oscillatory pattern based on an increased LF rhythmicity characterized the spontaneous variability of neural sympathetic discharge, R-R interval, and arterial pressure.

  17. Breathing difficulty - lying down

    MedlinePlus

    ... Paroxysmal nocturnal dyspnea; PND; Difficulty breathing while lying down; Orthopnea ... does not directly cause difficulty breathing while lying down but often worsens other conditions that lead to ...

  18. Parasympathetic Stimuli on Bronchial and Cardiovascular Systems in Humans

    PubMed Central

    Zannin, Emanuela; Pellegrino, Riccardo; Di Toro, Alessandro; Antonelli, Andrea; Dellacà, Raffaele L.; Bernardi, Luciano

    2015-01-01

    Background It is not known whether parasympathetic outflow simultaneously acts on bronchial tone and cardiovascular system waxing and waning both systems in parallel, or, alternatively, whether the regulation is more dependent on local factors and therefore independent on each system. The aim of this study was to evaluate the simultaneous effect of different kinds of stimulations, all associated with parasympathetic activation, on bronchomotor tone and cardiovascular autonomic regulation. Methods Respiratory system resistance (Rrs, forced oscillation technique) and cardio-vascular activity (heart rate, oxygen saturation, tissue oxygenation index, blood pressure) were assessed in 13 volunteers at baseline and during a series of parasympathetic stimuli: O2 inhalation, stimulation of the carotid sinus baroreceptors by neck suction, slow breathing, and inhalation of methacholine. Results Pure cholinergic stimuli, like O2 inhalation and baroreceptors stimulation, caused an increase in Rrs and a reduction in heart rate and blood pressure. Slow breathing led to bradycardia and hypotension, without significant changes in Rrs. However slow breathing was associated with deep inhalations, and Rrs evaluated at the baseline lung volumes was significantly increased, suggesting that the large tidal volumes reversed the airways narrowing effect of parasympathetic activation. Finally inhaled methacholine caused marked airway narrowing, while the cardiovascular variables were unaffected, presumably because of the sympathetic activity triggered in response to hypoxemia. Conclusions All parasympathetic stimuli affected bronchial tone and moderately affected also the cardiovascular system. However the response differed depending on the nature of the stimulus. Slow breathing was associated with large tidal volumes that reversed the airways narrowing effect of parasympathetic activation. PMID:26046774

  19. Shoulder and hip roll differences between breathing and non-breathing conditions in front crawl swimming.

    PubMed

    Psycharakis, Stelios G; McCabe, Carla

    2011-06-01

    The effects of breathing on body roll have been previously investigated for the roll of the whole trunk only. The purposes of this study were: to calculate separately the shoulder roll (SR) and hip roll (HR) of swimmers during front crawl for non-breathing and preferred-side breathing conditions; to assess the differences in the magnitude and temporal characteristics of these variables between non-breathing and preferred-side breathing conditions; and to examine their association with swimming performance (indicated by swimming speed). Twelve male swimmers who competed at national and international level performed two maximum 25 m front crawl trials: one non-breathing and one with breathing to their preferred side. Performance was recorded with four below and two above water synchronised cameras. SR and HR in both trials were calculated for the breathing and non-breathing sides. The timings of SR and HR peaks to each side and at the positions of neutral roll were also calculated. Swimming speed was significantly slower in the breathing trial (p < 0.01). Swimmers rolled their shoulders and hips to the breathing side significantly more in the breathing than in the non-breathing trial (SR: p < 0.01; HR: p = 0.03). Nevertheless, there were no significant differences in the overall SR or HR between these trials. In the breathing trial, SR was higher in the breathing than in the non-breathing side (p < 0.01) but HR was not significantly different (p = 0.07). There was no evidence to suggest that temporal characteristics of SR or HR were associated with swimming performance.

  20. Use of beat-to-beat cardiovascular variability data to determine the validity of sham therapy as the placebo control in osteopathic manipulative medicine research.

    PubMed

    Henley, Charles E; Wilson, Thad E

    2014-11-01

    Osteopathic manipulative medicine researchers often use sham therapy as the placebo control during clinical trials. Optimally, the sham therapy should be a hands-on procedure that is perceptually indistinguishable from osteopathic manipulative treatment, does not create an effect on its own, and is not a treatment intervention. However, the sham therapy itself may often influence the outcome. The use of cardiovascular variability (eg, beat-to-beat heart rate variability) as a surrogate for the autonomic nervous system is one objective method by which to identify such an effect. By monitoring cardiovascular variability, investigators can assess autonomic nervous system activity as a response to the sham therapy and quickly determine whether or not the selected sham therapy is a true placebo control. The authors provide evidence for assessment of beat-to-beat heart rate variability as one method for assuring objectivity of sham therapy as a placebo control in osteopathic manipulative medicine research.

  1. Variability in ozone-induced pulmonary injury and inflammation in healthy and cardiovascular-compromised rat models.

    PubMed

    Kodavanti, Urmila P; Ledbetter, Allen D; Thomas, Ronald F; Richards, Judy E; Ward, William O; Schladweiler, Mette C; Costa, Daniel L

    2015-01-01

    The molecular bases for variability in air pollutant-induced pulmonary injury due to underlying cardiovascular (CVD) and/or metabolic diseases are unknown. We hypothesized that healthy and genetic CVD-prone rat models will exhibit exacerbated response to acute ozone exposure dependent on the type and severity of disease. Healthy male 12-14-week-old Wistar Kyoto (WKY), Wistar (WS) and Sprague Dawley (SD); and CVD-compromised spontaneously hypertensive (SH), Fawn-Hooded hypertensive (FHH), stroke-prone spontaneously hypertensive (SHSP), obese spontaneously hypertensive heart failure (SHHF) and obese JCR (JCR) rats were exposed to 0.0, 0.25, 0.5, or 1.0 ppm ozone for 4 h; pulmonary injury and inflammation were analyzed immediately following (0-h) or 20-h later. Baseline bronchoalveolar lavage fluid (BALF) protein was higher in CVD strains except for FHH when compared to healthy. Ozone-induced increases in protein and inflammation were concentration-dependent within each strain but the degree of response varied from strain to strain and with time. Among healthy rats, SD were least affected. Among CVD strains, lean rats were more susceptible to protein leakage from ozone than obese rats. Ozone caused least neutrophilic inflammation in SH and SHHF while SHSP and FHH were most affected. BALF neutrophils and protein were poorly correlated when considering the entire dataset (r = 0.55). The baseline and ozone-induced increases in cytokine mRNA varied markedly between strains and did not correlate with inflammation. These data illustrate that the degree of ozone-induced lung injury/inflammation response is likely influenced by both genetic and physiological factors that govern the nature of cardiovascular compromise in CVD models.

  2. Heart Rate Variability Change Before and After Hemodialysis is Associated with Overall and Cardiovascular Mortality in Hemodialysis

    PubMed Central

    Chen, Szu-Chia; Huang, Jiun-Chi; Tsai, Yi-Chun; Hsiu-Chin Mai, R. N.; Jui-Hsin Chen, R. N.; Kuo, Po-Lin; Chang, Jer-Ming; Hwang, Shang-Jyh; Chen, Hung-Chun

    2016-01-01

    Low heart rate variability (HRV) has been recognized to correlate with adverse cardiovascular (CV) outcomes in hemodialysis (HD) patients. It has been reported that HRV might be improved after HD, but whether the improved HRV after HD predicts a better CV prognosis remains to be determined. This study examined the ability of the change in HRV before and after HD in predicting overall and CV mortality in HD patients. This study enrolled 182 patients under maintenance HD. HRV was examined to assess changes before and after HD. The change in HRV (ΔHRV) was defined as post-HD HRV minus pre-HD HRV. During a median follow-up period of 35.2 months, 29 deaths (15.9%) were recorded. Multivariate analysis showed that decreased ΔLF% was associated with increased overall (hazard ratios [HR], 0.978; 95% confidence interval [CI], 0.961–0.996; p = 0.019) and CV mortality (HR, 0.941; 95% CI, 0.914–0.970; p < 0.001), respectively. Moreover, adding ΔLF% to a clinical model provided an additional benefit in the prediction of overall (p = 0.002) and CV mortality (p < 0.001). HRV change before and after HD (ΔHRV) is an useful clinical marker, and it is stronger than HRV before HD in predicting overall and CV mortality. PMID:26854202

  3. Skinfold thickness is related to cardiovascular autonomic control as assessed by heart rate variability and heart rate recovery.

    PubMed

    Esco, Michael R; Williford, Henry N; Olson, Michele S

    2011-08-01

    The purpose of this study was to determine if heart rate recovery (HRR) and heart rate variability (HRV) are related to maximal aerobic fitness and selected body composition measurements. Fifty men (age = 21.9 ± 3.0 years, height = 180.8 ± 7.2 cm, weight = 80.4 ± 9.1 kg, volunteered to participate in this study. For each subject, body mass index (BMI), waist circumference (WC), and the sum of skinfolds across the chest, abdomen, and thigh regions (SUMSF) were recorded. Heart rate variability (HRV) was assessed during a 5-minute period while the subjects rested in a supine position. The following frequency domain parameters of HRV were recorded: normalized high-frequency power (HFnu), and low-frequency to high-frequency power ratio (LF:HF). To determine maximal aerobic fitness (i.e., VO2max), each subject performed a maximal graded exercise test on a treadmill. Heart rate recovery was recorded 1 (HRR1) and 2 (HRR2) minutes during a cool-down period. Mean VO2max and BMI for all the subjects were 49.5 ± 7.5 ml·kg(-1)·min(-1) and 24.7 ± 2.2 kg·m(-2), respectively. Although VO2max, WC, and SUMSF was each significantly correlated to HRR and HRV, only SUMSF had a significant independent correlation to HRR1, HRR2, HFnu, LF:HF (p < 0.01). The results of the regression procedure showed that SUMSF accounted for the greatest variance in HRR1, HRR2, HFnu, and LF:HF (p < 0.01). The results of this study suggest that cardiovascular autonomic modulation is significantly related to maximal aerobic fitness and body composition. However, SUMSF appears to have the strongest independent relationship with HRR and HRV, compared to other body composition parameters and VO2max.

  4. Effects of nitric oxide synthesis inhibitor or fluoxetine treatment on depression-like state and cardiovascular changes induced by chronic variable stress in rats.

    PubMed

    Almeida, Jeferson; Duarte, Josiane O; Oliveira, Leandro A; Crestani, Carlos C

    2015-01-01

    Comorbidity between mood disorders and cardiovascular disease has been described extensively. However, available antidepressants can have cardiovascular side effects. Treatment with selective inhibitors of neuronal nitric oxide synthase (nNOS) induces antidepressant effects, but whether the antidepressant-like effects of these drugs are followed by cardiovascular changes has not been previously investigated. Here, we tested in male rats exposed to chronic variable stress (CVS) the hypothesis that nNOS blockers are advantageous compared with conventional antidepressants in terms of cardiovascular side effects. We compared the effects of chronic treatment with the preferential nNOS inhibitor 7-nitroindazole (7-NI) with those evoked by the conventional antidepressant fluoxetine on alterations that are considered as markers of depression (immobility in the forced swimming test, FST, decreased body weight gain and increased plasma corticosterone concentration) and cardiovascular changes caused by CVS. Rats were exposed to a 14-day CVS protocol, while being concurrently treated daily with either 7-NI (30 mg/kg) or fluoxetine (10 mg/kg). Fluoxetine and 7-NI prevented the increase in immobility in the FST induced by CVS and reduced plasma corticosterone concentration in stressed rats. Both these treatments also prevented the CVS-evoked reduction of the depressor response to vasodilator agents and baroreflex changes. Fluoxetine and 7-NI-induced cardiovascular changes independent of stress exposure, including cardiac autonomic imbalance, increased intrinsic heart rate and vascular sympathetic modulation, a reduction of the pressor response to vasoconstrictor agents, and impairment of baroreflex activity. Altogether, these findings provide evidence that fluoxetine and 7-NI have similar effects on the depression-like state induced by CVS and on cardiovascular function.

  5. Effects of nitric oxide synthesis inhibitor or fluoxetine treatment on depression-like state and cardiovascular changes induced by chronic variable stress in rats.

    PubMed

    Almeida, Jeferson; Duarte, Josiane O; Oliveira, Leandro A; Crestani, Carlos C

    2015-01-01

    Comorbidity between mood disorders and cardiovascular disease has been described extensively. However, available antidepressants can have cardiovascular side effects. Treatment with selective inhibitors of neuronal nitric oxide synthase (nNOS) induces antidepressant effects, but whether the antidepressant-like effects of these drugs are followed by cardiovascular changes has not been previously investigated. Here, we tested in male rats exposed to chronic variable stress (CVS) the hypothesis that nNOS blockers are advantageous compared with conventional antidepressants in terms of cardiovascular side effects. We compared the effects of chronic treatment with the preferential nNOS inhibitor 7-nitroindazole (7-NI) with those evoked by the conventional antidepressant fluoxetine on alterations that are considered as markers of depression (immobility in the forced swimming test, FST, decreased body weight gain and increased plasma corticosterone concentration) and cardiovascular changes caused by CVS. Rats were exposed to a 14-day CVS protocol, while being concurrently treated daily with either 7-NI (30 mg/kg) or fluoxetine (10 mg/kg). Fluoxetine and 7-NI prevented the increase in immobility in the FST induced by CVS and reduced plasma corticosterone concentration in stressed rats. Both these treatments also prevented the CVS-evoked reduction of the depressor response to vasodilator agents and baroreflex changes. Fluoxetine and 7-NI-induced cardiovascular changes independent of stress exposure, including cardiac autonomic imbalance, increased intrinsic heart rate and vascular sympathetic modulation, a reduction of the pressor response to vasoconstrictor agents, and impairment of baroreflex activity. Altogether, these findings provide evidence that fluoxetine and 7-NI have similar effects on the depression-like state induced by CVS and on cardiovascular function. PMID:26068517

  6. Breathing in fetal lambs: the effect of brain stem section.

    PubMed

    Dawes, G S; Gardner, W N; Johnston, B M; Walker, D W

    1983-02-01

    The effects of section of the brain stem caudally (through the upper pons or mid-collicular) or rostrally (through the caudal hypothalamus or anterior commissure-suprachiasmatic nucleus) were studied in fetal lambs from 118 days gestation, after recovery in utero. In lambs sectioned caudally, breathing movements and electrocortical activity were dissociated. After some days recovery breathing tended to become continuous, with an abnormal prolongation of inspiratory time. Isocapnic hypoxia caused an increase in the rate and amplitude of breathing. After carotid denervation hypoxia still caused an increase in the amplitude of breathing. In lambs sectioned rostrally, there was also dissociation between breathing movements and electrocortical activity. Breathing remained episodic, with an incidence similar to that of intact fetal lambs. In two lambs after 10 days of recovery the breathing and electrocortical rhythms returned, from time to time, to their normal phasic relationship. Isocapnic hypoxia caused a diminution or arrest of breathing, as in intact lambs. The cardiovascular effects of transection were examined. Baroreflex sensitivity was normal in those lambs sectioned caudally and enhanced in those sectioned rostrally. It is concluded first that as a result of rostral section, independent episodic rhythms of fetal breathing and electrocortical activity can be dissociated. Secondly, moderate isocapnic hypoxia causes arrest of fetal breathing indirectly, requiring the integrity of a suprapontine mechanism. And thirdly, after caudal section of the brain stem, hypoxia causes enhancement of fetal breathing efforts, independently of the carotid chemoreceptors. Possible mechanisms are discussed. PMID:6875894

  7. Minimizing Shortness of Breath

    MedlinePlus

    ... Top Doctors in the Nation Departments & Divisions Home Health Insights Stress & Relaxation Breathing and Relaxation Minimizing Shortness of Breath ... Management Assess Your Stress Coping Strategies Identifying ... & Programs Health Insights Doctors & Departments Research & Science Education & Training Make ...

  8. Breathing and Relaxation

    MedlinePlus

    ... Top Doctors in the Nation Departments & Divisions Home Health Insights Stress & Relaxation Breathing and Relaxation Breathing and Relaxation Make ... Management Assess Your Stress Coping Strategies Identifying ... & Programs Health Insights Doctors & Departments Research & Science Education & Training Make ...

  9. [SLEEP DISORDERED BREATHING AND EPILEPSY: RELATIONSHIPS AND THERAPEUTIC CONSIDERATIONS].

    PubMed

    Faludi, Béla; Bóné, Beáta; Komoly, Sámuel; Janszky, József

    2015-11-30

    The importance of the sleep related breathing disorders (obstructive sleep apnea syndrome, central sleep apnea, and Cheyne-Stokes breathing) in the pathophysiology crebro- and cardiovascular disorders is well known. The relationship of sleep related breathing abnormalities and epilepsy is also important but underestimated in the daily practice. The relation is bidirectional. The breathing abnormalities in sleep may play important role in generating epileptic seizure, but the adverse effect of seizure and antiepileptic therapy (generation of apneas and hypopneas) may worsen the seizure control. The effect of new therapies (vagal nerve and deep brain stimulation) on the sleep architecture and sleep disordered breathing must be examined and discussed. Here we present a brief case of epileptic patient with deep brain stimulation therapy on sleep as well. The examination of the sleep related breathing abnormalities in epilepsy patient may help improve the effectiveness of antiepileptic therapy.

  10. Motivational processes and behavioral inhibition in breath holding.

    PubMed

    Alpher, V S; Blanton, R L

    1991-01-01

    Large individual differences in breathing performance have made it difficult to investigate the effects of psychological variables on respiratory parameters. This study uses an experimental approach to investigating the effects of attentional and motivational factors on breath-holding span in humans. The effects of shock threat (negative incentive), monetary reward (positive incentive), and mantra meditation (attentional control) on breath-holding span at functional residual capacity (FRC) were compared. Based on Jeffrey Gray's (1975, 1987) theory of behavioral inhibition, it was predicted that shock threat would extend FRC breath holding. Breath holding was increased under the shock threat condition but not under the monetary reward or mantra meditation conditions.

  11. Applications of breath gas analysis in medicine

    NASA Astrophysics Data System (ADS)

    Amann, Anton; Poupart, Guy; Telser, Stefan; Ledochowski, Maximilian; Schmid, Alex; Mechtcheriakov, Sergei

    2004-12-01

    Volatile organic compounds (VOCs) in exhaled breath gas provide valuable information about the subjects' physiological and pathophysiological condition. Proton-transfer-reaction mass spectrometry (PTR-MS) allows rapid and online measurements of these substances. We present results of three studies illustrating the potential of breath gas analysis by PTR-MS in various contexts: long-time online monitoring of VOCs in sleeping subjects suggests that VOC profiles are related to sleep stages. Analysis of VOC concentrations in the breath of carbohydrate malabsorbers emphasizes the role played by bacteria in the gut. Finally, we demonstrate the large intra- and intersubject concentration variability of VOCs by considering one particular mass.

  12. An introduction to the psychophysiology of breathing.

    PubMed

    Ley, R

    1994-06-01

    Breathing can be viewed as an independent variable which affects emotion, cognition, and behavior as well as a dependent variable which reflects changes in emotion, cognition, and behavior. This bidirectional interaction is basic to an appreciation of the significance of breathing in terms of its relevance in research and application. The underlying premise of the present article is that since breathing is a behavior that is under voluntary as well as reflexive control, it can be modified according to the principles of both instrumental training (operant conditioning) and Pavlovian (classical) conditioning. The implications of this premise are relevant to theory, diagnosis, and treatment of stress and anxiety-related disorders (e.g., panic disorder, phobias, test anxiety, occupational strain, and related psychosomatic disorders), and to basic and applied research in the psychophysiology of breathing.

  13. Decreased chewing activity during mouth breathing.

    PubMed

    Hsu, H-Y; Yamaguchi, K

    2012-08-01

    This study examined the effect of mouth breathing on the strength and duration of vertical effect on the posterior teeth using related functional parameters during 3 min of gum chewing in 39 nasal breathers. A CO(2) sensor was placed over the mouth to detect expiratory airflow. When no airflow was detected from the mouth throughout the recording period, the subject was considered a nasal breather and enrolled in the study. Electromyographic (EMG) activity was recorded during 3 min of gum chewing. The protocol was repeated with the nostrils occluded. The strength of the vertical effect was obtained as integrated masseter muscle EMG activity, and the duration of vertical effect was also obtained as chewing stroke count, chewing cycle variation and EMG activity duration above baseline. Baseline activity was obtained from the isotonic EMG activity during jaw movement at 1.6 Hz without making tooth contact. The duration represented the percentage of the active period above baseline relative to the 3-min chewing period. Paired t-test and repeated analysis of variance were used to compare variables between nasal and mouth breathing. The integrated EMG activity and the duration of EMG activity above baseline, chewing stroke count and chewing cycle significantly decreased during mouth breathing compared with nasal breathing (P<0.05). Chewing cycle variance during mouth breathing was significantly greater than nasal breathing (P<0.05). Mouth breathing reduces the vertical effect on the posterior teeth, which can affect the vertical position of posterior teeth negatively, leading to malocclusion.

  14. Model-free causality analysis of cardiovascular variability detects the amelioration of autonomic control in Parkinson's disease patients undergoing mechanical stimulation.

    PubMed

    Bassani, Tito; Bari, Vlasta; Marchi, Andrea; Tassin, Stefano; Dalla Vecchia, Laura; Canesi, Margherita; Barbic, Franca; Furlan, Raffaello; Porta, Alberto

    2014-07-01

    We tested the hypothesis that causality analysis, applied to the spontaneous beat-to-beat variability of heart period (HP) and systolic arterial pressure (SAP), can identify the improvement of autonomic control linked to plantar mechanical stimulation in patients with Parkinson's disease (PD). A causality index, measuring the strength of the association from SAP to HP variability, and derived according to the Granger paradigm (i.e. SAP causes HP if the inclusion of SAP into the set of signals utilized to describe cardiovascular interactions improves the prediction of HP series), was calculated using both linear model-based (MB) and nonlinear model-free (MF) approaches. Univariate HP and SAP variability indices in time and frequency domains, and bivariate descriptors of the HP-SAP variability interactions were computed as well. We studied ten PD patients (age range: 57-78 years; Hoehn-Yahr scale: 2-3; six males, four females) without orthostatic hypotension or symptoms of orthostatic intolerance and 'on-time' according to their habitual pharmacological treatment. PD patients underwent recordings at rest in a supine position and during a head-up tilt before, and 24 h after, mechanical stimulation was applied to the plantar surface of both feet. The MF causality analysis indicated a greater involvement of baroreflex in regulating HP-SAP variability interactions after mechanical stimulation. Remarkably, MB causality and more traditional univariate or bivariate techniques could not detect changes in cardiovascular regulation after mechanical stimulation, thus stressing the importance of accounting for nonlinear dynamics in PD patients. Due to the higher statistical power of MF causality we suggest its exploitation to monitor the baroreflex control improvement in PD patients, and we encourage the clinical application of the Granger causality approach to evaluate the modification of the autonomic control in relation to the application of a pharmacological treatment, a

  15. Spectral analysis of resting cardiovascular variables and responses to oscillatory LBNP before and after 6 degree head dowm bedrest

    NASA Technical Reports Server (NTRS)

    Knapp, Charles F.; Evans, J. M.; Patwardhan, A.; Levenhagen, D.; Wang, M.; Charles, John B.

    1991-01-01

    A major focus of our research program is to develop noninvasive procedures for determining changes in cardiovascular function associated with the null gravity environment. We define changes in cardiovascular function to be (1) the result of the regulatory system operating at values different from 'normal' but with an overall control system basically unchanged by the null gravity exposure, or (2) the result of operating with a control system that has significantly different regulatory characteristics after an exposure. To this end, we have used a model of weightlessness that consisted of exposing humans to 2 hrs. in the launch position, followed by 20 hrs. of 6 deg head down bedrest. Our principal objective was to use this model to measure cardiovascular responses to the 6 deg head down bedrest protocol and to develop the most sensitive 'systems identification' procedure for indicating change. A second objective, related to future experiments, is to use the procedure in combination with experiments designed to determine the degree to which a regulatory pathway has been altered and to determine the mechanisms responsible for the changes.

  16. Simulated breath waveform control

    NASA Technical Reports Server (NTRS)

    Bartlett, R. G.; Hendricks, C. M.; Morison, W. B.

    1972-01-01

    Subsystem was developed which provides twelve waveform controls to breath drive mechanism. Twelve position, magnetically actuated rotary switch is connected to one end of crankshaft drive, such that it makes one complete revolution for each simulated breath. Connections with common wired point are included in modifications made to standard motor speed controller.

  17. From breathing to respiration.

    PubMed

    Fitting, Jean-William

    2015-01-01

    The purpose of breathing remained an enigma for a long time. The Hippocratic school described breathing patterns but did not associate breathing with the lungs. Empedocles and Plato postulated that breathing was linked to the passage of air through pores of the skin. This was refuted by Aristotle who believed that the role of breathing was to cool the heart. In Alexandria, breakthroughs were accomplished in the anatomy and physiology of the respiratory system. Later, Galen proposed an accurate description of the respiratory muscles and the mechanics of breathing. However, his heart-lung model was hampered by the traditional view of two non-communicating vascular systems - veins and arteries. After a period of stagnation in the Middle Ages, knowledge progressed with the discovery of pulmonary circulation. The comprehension of the purpose of breathing progressed by steps thanks to Boyle and Mayow among others, and culminated with the contribution of Priestley and the discovery of oxygen by Lavoisier. Only then was breathing recognized as fulfilling the purpose of respiration, or gas exchange. A century later, a controversy emerged concerning the active or passive transfer of oxygen from alveoli to the blood. August and Marie Krogh settled the dispute, showing that passive diffusion was sufficient to meet the oxygen needs.

  18. From breathing to respiration.

    PubMed

    Fitting, Jean-William

    2015-01-01

    The purpose of breathing remained an enigma for a long time. The Hippocratic school described breathing patterns but did not associate breathing with the lungs. Empedocles and Plato postulated that breathing was linked to the passage of air through pores of the skin. This was refuted by Aristotle who believed that the role of breathing was to cool the heart. In Alexandria, breakthroughs were accomplished in the anatomy and physiology of the respiratory system. Later, Galen proposed an accurate description of the respiratory muscles and the mechanics of breathing. However, his heart-lung model was hampered by the traditional view of two non-communicating vascular systems - veins and arteries. After a period of stagnation in the Middle Ages, knowledge progressed with the discovery of pulmonary circulation. The comprehension of the purpose of breathing progressed by steps thanks to Boyle and Mayow among others, and culminated with the contribution of Priestley and the discovery of oxygen by Lavoisier. Only then was breathing recognized as fulfilling the purpose of respiration, or gas exchange. A century later, a controversy emerged concerning the active or passive transfer of oxygen from alveoli to the blood. August and Marie Krogh settled the dispute, showing that passive diffusion was sufficient to meet the oxygen needs. PMID:25532022

  19. Effects of Training and Detraining on Physical Fitness, Physical Activity Patterns, Cardiovascular Variables, and HRQoL after 3 Health-Promotion Interventions in Institutionalized Elders

    PubMed Central

    Lobo, Alexandrina; Carvalho, Joana; Santos, Paula

    2010-01-01

    The purpose of this study is to assess the effects of different strategies of health on the levels of physical activity (PA), physical fitness (PF), cardiovascular disease (CVD) risk factors and quality of life (QoL) of the institutionalized elderly. Concurrently studies were made of the effect of detraining on these same variables. In this investigation we carried out a prospective longitudinal study with an experimental design, with 1 year plus 3 months of a detraining period. Methodology. (a) A questionnaire with socio-demographic characteristics and a QoL scale (MOS SF-36); (b) Functional Fitness Test to assess PF; (c) An MTI Actigraph to evaluate the PA; (d) Biochemical analysis of blood, blood pressure and bio-impedance. The Main Results Indicated That: (i) ST significantly improved strength and body flexibility and AT the aerobic endurance, agility/dynamic balance and lower strength and flexibility; (ii) Implications of detraining were more evident on the PA groups in the lower body flexibility, which is associated with agility/dynamic balance and lower strength in the AT group; (iii) Cardiovascular variables improved significantly especially blood pressure, cholesterol and glucose in the ST and HDL in the AT group; not having undergone significant changes with the detraining. The results of this thesis contribute positively to highlight the importance of PA in the promotion of health, prevention and reduction of CVD risk factors and the improvement of the PF and QoL. PMID:22332008

  20. Effect of Pre- and Postoperative Phenylbutazone and Morphine Administration on the Breathing Response to Skin Incision, Recovery Quality, Behavior, and Cardiorespiratory Variables in Horses Undergoing Fetlock Arthroscopy: A Pilot Study.

    PubMed

    Conde Ruiz, Clara; Cruz Benedetti, Inga-Catalina; Guillebert, Isabelle; Portier, Karine Genevieve

    2015-01-01

    This prospective blinded randomized study aimed to determine whether the timing of morphine and phenylbutazone administration affects the breathing response to skin incision, recovery quality, behavior, and cardiorespiratory variables in horses undergoing fetlock arthroscopy. Ten Standardbred horses were premedicated with acepromazine (0.04 mg kg(-1) IM) and romifidine (0.04 mg kg(-1) IV). Anesthesia was induced with diazepam (0.05 mg kg(-1)) and ketamine (2.2 mg kg(-1)) IV at T0. Horses in group PRE (n = 5) received morphine (0.1 mg kg(-1)) and phenylbutazone (2.2 mg kg(-1)) IV after induction and an equivalent amount of saline after surgery. Horses in group POST (n = 5) received the inversed treatment. Anesthesia was maintained with isoflurane 2% in 100% oxygen. Hypotension (mean arterial pressure <60 mmHg) was treated with dobutamine. All horses breathed spontaneously. Dobutamine requirements, respiratory rate (f R), heart rate (HR), mean arterial blood pressure, end-tidal CO2, inspired (i) and expired (e) tidal and minute volume (V T and [Formula: see text]), inspiratory time (IT), and the inspiratory gas flow (V Ti/IT) were measured every 5 min. Data were averaged during four 15 min periods before (P1 and P2) and after the incision (P3 and P4). Serial blood-gas analyses were also performed. Recoveries were unassisted, video recorded, and scored by three anesthetists blinded to the treatment. The postoperative behavior of the horses (25 demeanors), HR, and f R were recorded at three time points before induction (T0-24 h, T0-12 h, and T0-2 h) and six time points after recovery (TR) (TR + 2, 4, 6, 12, 24, 48 h). Data were compared between groups using a Wilcoxon test and within groups using a Friedman test or a Kruskal-Wallis signed-rank test when applicable. Tidal volumes (V Te and V Ti) were higher in PRE than in POST during all the considered periods but the difference between groups was only significant during P2 (V Te in

  1. Effect of Pre- and Postoperative Phenylbutazone and Morphine Administration on the Breathing Response to Skin Incision, Recovery Quality, Behavior, and Cardiorespiratory Variables in Horses Undergoing Fetlock Arthroscopy: A Pilot Study

    PubMed Central

    Conde Ruiz, Clara; Cruz Benedetti, Inga-Catalina; Guillebert, Isabelle; Portier, Karine Genevieve

    2015-01-01

    This prospective blinded randomized study aimed to determine whether the timing of morphine and phenylbutazone administration affects the breathing response to skin incision, recovery quality, behavior, and cardiorespiratory variables in horses undergoing fetlock arthroscopy. Ten Standardbred horses were premedicated with acepromazine (0.04 mg kg−1 IM) and romifidine (0.04 mg kg−1 IV). Anesthesia was induced with diazepam (0.05 mg kg−1) and ketamine (2.2 mg kg−1) IV at T0. Horses in group PRE (n = 5) received morphine (0.1 mg kg−1) and phenylbutazone (2.2 mg kg−1) IV after induction and an equivalent amount of saline after surgery. Horses in group POST (n = 5) received the inversed treatment. Anesthesia was maintained with isoflurane 2% in 100% oxygen. Hypotension (mean arterial pressure <60 mmHg) was treated with dobutamine. All horses breathed spontaneously. Dobutamine requirements, respiratory rate (fR), heart rate (HR), mean arterial blood pressure, end-tidal CO2, inspired (i) and expired (e) tidal and minute volume (VT and V˙E), inspiratory time (IT), and the inspiratory gas flow (VTi/IT) were measured every 5 min. Data were averaged during four 15 min periods before (P1 and P2) and after the incision (P3 and P4). Serial blood–gas analyses were also performed. Recoveries were unassisted, video recorded, and scored by three anesthetists blinded to the treatment. The postoperative behavior of the horses (25 demeanors), HR, and fR were recorded at three time points before induction (T0–24 h, T0–12 h, and T0–2 h) and six time points after recovery (TR) (TR + 2, 4, 6, 12, 24, 48 h). Data were compared between groups using a Wilcoxon test and within groups using a Friedman test or a Kruskal–Wallis signed-rank test when applicable. Tidal volumes (VTe and VTi) were higher in PRE than in POST during all the considered periods but the difference between groups was only significant during P2 (VTe in mL kg−1

  2. Effect of Pre- and Postoperative Phenylbutazone and Morphine Administration on the Breathing Response to Skin Incision, Recovery Quality, Behavior, and Cardiorespiratory Variables in Horses Undergoing Fetlock Arthroscopy: A Pilot Study.

    PubMed

    Conde Ruiz, Clara; Cruz Benedetti, Inga-Catalina; Guillebert, Isabelle; Portier, Karine Genevieve

    2015-01-01

    This prospective blinded randomized study aimed to determine whether the timing of morphine and phenylbutazone administration affects the breathing response to skin incision, recovery quality, behavior, and cardiorespiratory variables in horses undergoing fetlock arthroscopy. Ten Standardbred horses were premedicated with acepromazine (0.04 mg kg(-1) IM) and romifidine (0.04 mg kg(-1) IV). Anesthesia was induced with diazepam (0.05 mg kg(-1)) and ketamine (2.2 mg kg(-1)) IV at T0. Horses in group PRE (n = 5) received morphine (0.1 mg kg(-1)) and phenylbutazone (2.2 mg kg(-1)) IV after induction and an equivalent amount of saline after surgery. Horses in group POST (n = 5) received the inversed treatment. Anesthesia was maintained with isoflurane 2% in 100% oxygen. Hypotension (mean arterial pressure <60 mmHg) was treated with dobutamine. All horses breathed spontaneously. Dobutamine requirements, respiratory rate (f R), heart rate (HR), mean arterial blood pressure, end-tidal CO2, inspired (i) and expired (e) tidal and minute volume (V T and [Formula: see text]), inspiratory time (IT), and the inspiratory gas flow (V Ti/IT) were measured every 5 min. Data were averaged during four 15 min periods before (P1 and P2) and after the incision (P3 and P4). Serial blood-gas analyses were also performed. Recoveries were unassisted, video recorded, and scored by three anesthetists blinded to the treatment. The postoperative behavior of the horses (25 demeanors), HR, and f R were recorded at three time points before induction (T0-24 h, T0-12 h, and T0-2 h) and six time points after recovery (TR) (TR + 2, 4, 6, 12, 24, 48 h). Data were compared between groups using a Wilcoxon test and within groups using a Friedman test or a Kruskal-Wallis signed-rank test when applicable. Tidal volumes (V Te and V Ti) were higher in PRE than in POST during all the considered periods but the difference between groups was only significant during P2 (V Te in

  3. Enhanced blood pressure variability in a high cardiovascular risk group of African Americans: FIT4Life Study.

    PubMed

    Veerabhadrappa, Praveen; Diaz, Keith M; Feairheller, Deborah L; Sturgeon, Kathleen M; Williamson, Sheara; Crabbe, Deborah L; Kashem, Abul; Ahrensfield, Debra; Brown, Michael D

    2010-01-01

    High blood pressure (BP) levels in African Americans elicit vascular inflammation resulting in vascular remodeling. BP variability (BPV) correlates with target organ damage. We aimed to investigate the relationship between inflammatory markers and BPV in African Americans. Thirty-six African Americans underwent 24-hour ambulatory BP monitoring (ABPM). BPV was calculated using the average real variability index. Fasting blood samples were assayed for high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-alpha), and white blood cell (WBC) count. Significant associations between hs-CRP and 24-hour systolic variability (r=0.50; P=.012) and awake systolic variability (r=0.45; P=.02) were identified after adjusting for age, body mass index, and 24-hour mean BP. ABPM variables were compared between the hs-CRP tertile groups. In post-hoc analysis, there was a significant difference in 24-hour and awake periods for both systolic and diastolic variability among the groups. TNF-alpha and WBC count showed no associations with ABPM variables. hs-CRP was associated with systolic variability, and higher levels of hs-CRP were related with greater BPV. Higher inflammatory status influences wider fluctuations in systolic BP, which in turn could facilitate early progression to target organ damage independent of absolute BP levels in African Americans.

  4. [Prevalence of mouth breathing in children from an elementary school].

    PubMed

    Felcar, Josiane Marques; Bueno, Izabele Rafael; Massan, Ana Carolina Silva; Torezan, Roberta Pereira; Cardoso, Jefferson Rosa

    2010-03-01

    The objective of this article is to identify the prevalence of mouth breathing in children from an elementary school. 496 questionnaires were answered by 1st and 4th grade children's parents or sponsors in order to identify mouth-breathing. There were questions about habits, sleeping, behavior, eating, personal care and breathing. Mann-Whitney and the Chi-square tests were used to compare the variables between mouth-breathing and nose-breathing among the groups. To measure the exposure effect of the explanatory variables on mouth breathing, the test of logistic regression was used and its magnitude was calculated through Odds Ratio. The statistical significance was set at 5%, and the rate of returned questionnaires was 84.5%. The prevalence of the mouthbreathing over this population was 56.8%. The average age was 7 years old (6-9). There was no significant statistical difference between genders, considering 49.1% male and 50.9% female. The final model of logistic regression identified the variables dribble, sleeps well (negative association) and snores as factors that predict the occurrence of the mouth-breathing. The prevalence of mouthbreathing was similar to related in the literature. The variables dribble, sleeps well (negative association) and snores may be factors that predict the occurrence of mouth-breathing.

  5. Association of cardiovascular risk using non-linear heart rate variability measures with the framingham risk score in a rural population

    PubMed Central

    Jelinek, Herbert F.; Md Imam, Hasan; Al-Aubaidy, Hayder; Khandoker, Ahsan H.

    2013-01-01

    Cardiovascular risk can be calculated using the Framingham cardiovascular disease (CVD) risk score and provides a risk stratification from mild to very high CVD risk percentage over 10 years. This equation represents a complex interaction between age, gender, cholesterol status, blood pressure, diabetes status, and smoking. Heart rate variability (HRV) is a measure of how the autonomic nervous system (ANS) modulates the heart rate. HRV measures are sensitive to age, gender, disease status such as diabetes and hypertension and processes leading to atherosclerosis. We investigated whether HRV measures are a suitable, simple, noninvasive alternative to differentiate between the four main Framingham associated CVD risk categories. In this study we applied the tone-entropy (T-E) algorithm and complex correlation measure (CCM) for analysis of HRV obtained from 20 min. ECG recordings and correlated the HRV score with the stratification results using the Framingham risk equation. Both entropy and CCM had significant analysis of variance (ANOVA) results [F(172, 3) = 9.51; <0.0001]. Bonferroni post hoc analysis indicated a significant difference between mild, high and very high cardiac risk groups applying tone-entropy (p < 0.01). CCM detected a difference in temporal dynamics of the RR intervals between the mild and very high CVD risk groups (p < 0.01). Our results indicate a good agreement between the T-E and CCM algorithm and the Framingham CVD risk score, suggesting that this algorithm may be of use for initial screening of cardiovascular risk as it is noninvasive, economical and easy to use in clinical practice. PMID:23898302

  6. Shortness-of-Breath

    MedlinePlus

    ... can lead to shortness of breath include anxiety, panic attacks, anemia and even constipation. The experience of shortness ... are used to treat patients with anxiety or panic attacks. Other commonly used drugs include bronchodilators to widen ...

  7. Stop, Breathe & Think app.

    PubMed

    Shaw, Natalie

    2014-07-15

    The Stop, Breathe & Think app is free, thanks to underwriting from Tools for Peace, the non-profit organisation that teaches people of all ages how to develop and apply kindness and compassion in their daily lives.

  8. Breath holding spell

    MedlinePlus

    ... such as Riley-Day syndrome or Rett syndrome Iron deficiency anemia A family history of breath holding spells ( ... tests may be done to check for an iron deficiency. Other tests that may be done include: EKG ...

  9. Shortness of Breath

    MedlinePlus

    ... deep breath, which usually results in retention of carbon dioxide and not enough oxygen in blood (obesity hypoventilation ... for anemia), and oximetry or blood oxygen or carbon dioxide levels. Your doctor also may obtain a chest ...

  10. Are 30 minutes of rest between two incremental shuttle walking tests enough for cardiovascular variables and perceived exertion to return to baseline values?

    PubMed Central

    Ribeiro, Laís R. G.; Mesquita, Rafael B.; Vidotto, Laís S.; Merli, Myriam F.; Carvalho, Débora R.; de Castro, Larissa A.; Probst, Vanessa S.

    2015-01-01

    Objective: To verify whether 30 minutes of rest between two incremental shuttle walking tests (ISWT) are enough for cardiovascular variables and perceived exertion to return to baseline values in healthy subjects in a broad age range. Method: The maximal exercise capacity of 334 apparently healthy subjects (age ≥18) was evaluated using the ISWT. The test was performed twice with 30 minutes of rest in between. Heart rate (HR), arterial blood pressure (ABP), dyspnea, and leg fatigue were evaluated before and after each test. Subjects were allocated to 6 groups according to their age: G1: 18-29 years; G2: 30-39 years; G3: 40-49 years; G4: 50-59 years; G5: 60-69 years and G6: ≥70 years. Results: All groups had a good performance in the ISWT (median >90% of the predicted distance). The initial HR (HRi) of the second ISWT was higher than the first ISWT in the total sample (p<0.0001), as well as in all groups (p<0.0001). No difference was observed in the behavior of ABP (systolic and diastolic) and dyspnea between the two tests, but this difference occurred for leg fatigue (greater before the second ISWT) in G1 (p<0.05). Most subjects (58%) performed better in the second test. Conclusion: 30 minutes of rest between two ISWTs are not enough for all cardiovascular variables and perceived exertion to return to baseline values. However, this period appears to be sufficient for blood pressure and performance to recover in most subjects. PMID:25789556

  11. Astronaut Preflight Cardiovascular Variables Associated with Vascular Compliance are Highly Correlated with Post-Flight Eye Outcome Measures in the Visual Impairment Intracranial Pressure (VIIP) Syndrome Following Long Duration Spaceflight

    NASA Technical Reports Server (NTRS)

    Otto, Christian; Ploutz-Snyder, R.

    2015-01-01

    The detection of the first VIIP case occurred in 2005, and adequate eye outcome measures were available for 31 (67.4%) of the 46 long duration US crewmembers who had flown on the ISS since its first crewed mission in 2000. Therefore, this analysis is limited to a subgroup (22 males and 9 females). A "cardiovascular profile" for each astronaut was compiled by examining twelve individual parameters; eleven of these were preflight variables: systolic blood pressure, pulse pressure, body mass index, percentage body fat, LDL, HDL, triglycerides, use of anti-lipid medication, fasting serum glucose, and maximal oxygen uptake in ml/kg. Each of these variables was averaged across three preflight annual physical exams. Astronaut age prior to the long duration mission, and inflight salt intake was also included in the analysis. The group of cardiovascular variables for each crew member was compared with seven VIIP eye outcome variables collected during the immediate post-flight period: anterior-posterior axial length of the globe measured by ultrasound and optical biometry; optic nerve sheath diameter, optic nerve diameter, and optic nerve to sheath ratio- each measured by ultrasound and magnetic resonance imaging (MRI), intraocular pressure (IOP), change in manifest refraction, mean retinal nerve fiber layer (RNFL) on optical coherence tomography (OCT), and RNFL of the inferior and superior retinal quadrants. Since most of the VIIP eye outcome measures were added sequentially beginning in 2005, as knowledge of the syndrome improved, data were unavailable for 22.0% of the outcome measurements. To address the missing data, we employed multivariate multiple imputation techniques with predictive mean matching methods to accumulate 200 separate imputed datasets for analysis. We were able to impute data for the 22.0% of missing VIIP eye outcomes. We then applied Rubin's rules for collapsing the statistical results across our 200 multiply imputed data sets to assess the canonical

  12. Chironex fleckeri (box jellyfish) venom proteins: expansion of a cnidarian toxin family that elicits variable cytolytic and cardiovascular effects.

    PubMed

    Brinkman, Diane L; Konstantakopoulos, Nicki; McInerney, Bernie V; Mulvenna, Jason; Seymour, Jamie E; Isbister, Geoffrey K; Hodgson, Wayne C

    2014-02-21

    The box jellyfish Chironex fleckeri produces extremely potent and rapid-acting venom that is harmful to humans and lethal to prey. Here, we describe the characterization of two C. fleckeri venom proteins, CfTX-A (∼40 kDa) and CfTX-B (∼42 kDa), which were isolated from C. fleckeri venom using size exclusion chromatography and cation exchange chromatography. Full-length cDNA sequences encoding CfTX-A and -B and a third putative toxin, CfTX-Bt, were subsequently retrieved from a C. fleckeri tentacle cDNA library. Bioinformatic analyses revealed that the new toxins belong to a small family of potent cnidarian pore-forming toxins that includes two other C. fleckeri toxins, CfTX-1 and CfTX-2. Phylogenetic inferences from amino acid sequences of the toxin family grouped CfTX-A, -B, and -Bt in a separate clade from CfTX-1 and -2, suggesting that the C. fleckeri toxins have diversified structurally and functionally during evolution. Comparative bioactivity assays revealed that CfTX-1/2 (25 μg kg(-1)) caused profound effects on the cardiovascular system of anesthetized rats, whereas CfTX-A/B elicited only minor effects at the same dose. Conversely, the hemolytic activity of CfTX-A/B (HU50 = 5 ng ml(-1)) was at least 30 times greater than that of CfTX-1/2. Structural homology between the cubozoan toxins and insecticidal three-domain Cry toxins (δ-endotoxins) suggests that the toxins have a similar pore-forming mechanism of action involving α-helices of the N-terminal domain, whereas structural diversification among toxin members may modulate target specificity. Expansion of the cnidarian toxin family therefore provides new insights into the evolutionary diversification of box jellyfish toxins from a structural and functional perspective. PMID:24403082

  13. Prevalence of cardiovascular risk factors, the association with socioeconomic variables in adolescents from low-income region.

    PubMed

    Nascimento-Ferreira, Marcus Vinicius; De Moraes, Augusto Cesar F; Carvalho, Heraclito B; Moreno, Luis A; Gomes Carneiro, André Luiz; dos Reis, Victor Manuel M; Torres-Leal, Francisco Leonardo

    2014-01-01

    Objetivos: Estimar la prevalencia de obesidad y sobrepeso, obesidad abdominal y hipertensión arterial en una muestra de adolescentes pertenecientes a una ciudad de baja renta en Brasil y su relación con el nivel socioeconómico, nivel educativo de lo responsable de la familia y tipo de escuela. Métodos: Estudio transversal con una muestra de 1014 adolescentes (54,8% chicas), con edades entre 14-19 años, estudiantes de las escuelas de la ciudad de Imperatriz (Brasil), seleccionadas por un muestreo aleatorio. Las variables dependientes evaluadas son: obesidad general y sobrepeso, obesidad abdominal, y tensión arterial alta (sistólica y/o diastólica). Las variables independientes son: nivel socioeconómico de la familia (NSO), el nivel de educación de lo responsable de la familia (NERF) y tipo de escuela. Las variables de confusión son: sexo, edad y nivel de actividad física. La prevalencia fue estimada, y la asociación entre las variables dependientes y las variables independientes se analizaron mediante razón de prevalencia (RP), con intervalo de confianza (IC) del 95%, estimado por la regresión de Poisson. Resultados: La prevalencia de la obesidad general fue de 3,8%, sobrepeso 13,1%, obesidad abdominal 22,7% y la tesión arterial alta 21,3%. Las análisis ajustadas indicaron que las chicas con NSO alto tienen mayor probabilidad de tener sobrepeso (RP=1,71 [IC95%: 1,13 a 2,87]), y chicos de las escuelas privadas tienen más probabilidad de tener obesidad (RP=1,79 [IC95%: 1.04- 3,08]) y obesidad abdominal (RP=1,64 [IC95%: 1,06 a 2,54]). Conclusión: La prevalencia de los FRC es alta en adolescentes de una región de baja renta. Los chicos de las escuelas privadas son más propensos a tener obesi dad y obesidad abdominal, y las chicas con NSO alto son más propensas a tener sobrepeso.

  14. Visit-to-Visit Variability and Reduction in Blood Pressure After a 3-Month Cardiac Rehabilitation Program in Patients With Cardiovascular Disease.

    PubMed

    Ishida, Toshihisa; Miura, Shin-Ichiro; Fujimi, Kanta; Ueda, Takashi; Ueda, Yoko; Matsuda, Takuro; Sakamoto, Maaya; Arimura, Tadaaki; Shiga, Yuhei; Kitajima, Ken; Saku, Keijiro

    2016-09-28

    Visit-to-visit variability (VVV) in blood pressure (BP) has been shown to be a predictor of cardiovascular events. It is unknown whether CR can improve VVV in BP as well as reducing BP. We enrolled 84 patients who had cardiovascular disease (CVD) and participated in a 3-month CR program. We measured systolic and diastolic BP (SBP and DBP), pulse pressure (PP), and heart rate (HR) before exercise training at each visit and determined VVV in BP or HR expressed as the standard deviation of the average BP or HR. Patients who had uncontrolled BP at baseline and who did not change their antihypertensive drugs throughout the study period showed a significant reduction of both SBP and DBP with a decrease in PP after 3 months. Patients who did not change their antihypertensive drugs were divided into larger (L-) and smaller (S-) VVV in the SBP groups and L- and S-VVV in the DBP groups according to the average value of VVV in SBP or DBP. In the L-VVV in the SBP and DBP groups, VVV in SBP and DBP in the 1st month was significantly decreased after the 3rd month in both groups. HR at baseline was significantly decreased after 3 months. In addition, CR induced a significant increase in the level of high-density lipoprotein cholesterol (HDL-C) in blood. In conclusion, CR improved VVV in BP in patients with L-VVV in BP and evoked a significant reduction in HR and an increase in HDL-C. These effects due to the CR program may be cardioprotective.

  15. Cardiovascular Parameters and Neural Sympathetic Discharge Variability before Orthostatic Syncope: Role of Sympathetic Baroreflex Control to the Vessels

    PubMed Central

    Barbic, Franca; Heusser, Karsten; Marchi, Andrea; Zamunér, Antonio Roberto; Gauger, Peter; Tank, Jens; Jordan, Jens; Diedrich, André; Robertson, David; Dipaola, Franca; Achenza, Sara; Porta, Alberto; Furlan, Raffaello

    2016-01-01

    We tested the hypothesis that altered sympathetic baroreceptor control to the vessels (svBRS) and disrupted coupling between blood pressure (BP) fluctuations and muscle sympathetic activity (MSNA) discharge pattern in the low frequency band (LF, around 0.1Hz) precede vasovagal syncope. Seven healthy males underwent ECG, BP, respiratory, and MSNA recordings at baseline (REST) and during a 15-minute 80° head-up tilt followed by a −10 mmHg step wise increase of lower body negative pressure up to presyncope. Spectral and coherence analyses of systolic arterial pressure (SAP) and MSNA variability provided the indexes of vascular sympathetic modulation, LFSAP, and of the linear coupling between MSNA and SAP in the low frequency band (around 0.1 Hz), K2MSNA-SAP(LF). svBRS was assessed as the slope of the regression line between MSNA and diastolic arterial pressure (DAP). Data were analyzed at REST, during asymptomatic and presyncope periods of tilt. svBRS declined during presyncope period compared to REST and asymptomatic tilt. The presyncope period was characterized by a decrease of RR interval, LFMSNA, LFSAP, and K2MSNA-SAP(LF) values compared to the asymptomatic one, whereas MSNA burst rate was unchanged. The reduction of svBRS producing an altered coupling between MSNA and SAP variability at 0.1 Hz, may provoke circulatory changes leading to presyncope. PMID:25798786

  16. Cardiovascular parameters and neural sympathetic discharge variability before orthostatic syncope: role of sympathetic baroreflex control to the vessels.

    PubMed

    Barbic, Franca; Heusser, Karsten; Marchi, Andrea; Zamunér, Antonio Roberto; Gauger, Peter; Tank, Jens; Jordan, Jens; Diedrich, André; Robertson, David; Dipaola, Franca; Achenza, Sara; Porta, Alberto; Furlan, Raffaello

    2015-04-01

    We tested the hypothesis that altered sympathetic baroreceptor control to the vessels (svBRS) and disrupted coupling between blood pressure (BP) fluctuations and muscle sympathetic activity (MSNA) discharge pattern in the low frequency band (LF, around 0.1 Hz) precede vasovagal syncope. Seven healthy males underwent ECG, BP, respiratory, and MSNA recordings at baseline (REST) and during a 15 min 80° head-up tilt, followed by a -10 mmHg step wise increase of lower body negative pressure up to presyncope. Spectral and coherence analyses of systolic arterial pressure (SAP) and MSNA variability provided the indexes of vascular sympathetic modulation, LFSAP, and of the linear coupling between MSNA and SAP in the low frequency band (around 0.1 Hz), K(2)MSNA-SAP(LF). svBRS was assessed as the slope of the regression line between MSNA and diastolic arterial pressure (DAP). Data were analyzed at REST, during asymptomatic and presyncope periods of tilt. svBRS declined during presyncope period compared to REST and asymptomatic tilt. The presyncope period was characterized by a decrease of RR interval, LFMSNA, LFSAP, and K(2)MSNA-SAP(LF) values compared to the asymptomatic one, whereas MSNA burst rate was unchanged. The reduction of svBRS producing an altered coupling between MSNA and SAP variability at 0.1 Hz, may provoke circulatory changes leading to presyncope. PMID:25798786

  17. Music structure determines heart rate variability of singers

    PubMed Central

    Vickhoff, Björn; Malmgren, Helge; Åström, Rickard; Nyberg, Gunnar; Ekström, Seth-Reino; Engwall, Mathias; Snygg, Johan; Nilsson, Michael; Jörnsten, Rebecka

    2013-01-01

    Choir singing is known to promote wellbeing. One reason for this may be that singing demands a slower than normal respiration, which may in turn affect heart activity. Coupling of heart rate variability (HRV) to respiration is called Respiratory sinus arrhythmia (RSA). This coupling has a subjective as well as a biologically soothing effect, and it is beneficial for cardiovascular function. RSA is seen to be more marked during slow-paced breathing and at lower respiration rates (0.1 Hz and below). In this study, we investigate how singing, which is a form of guided breathing, affects HRV and RSA. The study comprises a group of healthy 18 year olds of mixed gender. The subjects are asked to; (1) hum a single tone and breathe whenever they need to; (2) sing a hymn with free, unguided breathing; and (3) sing a slow mantra and breathe solely between phrases. Heart rate (HR) is measured continuously during the study. The study design makes it possible to compare above three levels of song structure. In a separate case study, we examine five individuals performing singing tasks (1–3). We collect data with more advanced equipment, simultaneously recording HR, respiration, skin conductance and finger temperature. We show how song structure, respiration and HR are connected. Unison singing of regular song structures makes the hearts of the singers accelerate and decelerate simultaneously. Implications concerning the effect on wellbeing and health are discussed as well as the question how this inner entrainment may affect perception and behavior. PMID:23847555

  18. Cardiovascular group

    NASA Technical Reports Server (NTRS)

    Blomqvist, Gunnar

    1989-01-01

    As a starting point, the group defined a primary goal of maintaining in flight a level of systemic oxygen transport capacity comparable to each individual's preflight upright baseline. The goal of maintaining capacity at preflight levels would seem to be a reasonable objective for several different reasons, including the maintenance of good health in general and the preservation of sufficient cardiovascular reserve capacity to meet operational demands. It is also important not to introduce confounding variables in whatever other physiological studies are being performed. A change in the level of fitness is likely to be a significant confounding variable in the study of many organ systems. The principal component of the in-flight cardiovascular exercise program should be large-muscle activity such as treadmill exercise. It is desirable that at least one session per week be monitored to assure maintenance of proper functional levels and to provide guidance for any adjustments of the exercise prescription. Appropriate measurements include evaluation of the heart-rate/workload or the heart-rate/oxygen-uptake relationship. Respiratory gas analysis is helpful by providing better opportunities to document relative workload levels from analysis of the interrelationships among VO2, VCO2, and ventilation. The committee felt that there is no clear evidence that any particular in-flight exercise regimen is protective against orthostatic hypotension during the early readaptation phase. Some group members suggested that maintenance of the lower body muscle mass and muscle tone may be helpful. There is also evidence that late in-flight interventions to reexpand blood volume to preflight levels are helpful in preventing or minimizing postflight orthostatic hypotension.

  19. Life and Breath

    ERIC Educational Resources Information Center

    Ellis, Helen D.

    1974-01-01

    This article describes a public education program combining the screening process and a follow-up program for teaching victims of emphysema and other respiratory diseases how to better their living condition through proper breathing, avoidance of air pollutants and cigarette smoking, and taking better care of themselves physically. (PD)

  20. Metabolic breath analyzer

    NASA Technical Reports Server (NTRS)

    Perry, C. L.

    1971-01-01

    Instrument measures metabolic breathing rate and dynamics of human beings in atmospheres ranging from normal air to 100 percent oxygen at ambient pressures from 14.7 to 3.0 psia. Measurements are made at rest or performing tasks up to maximum physical capacity under either zero or normal gravity.

  1. Breathing Like a Fish

    ERIC Educational Resources Information Center

    Katsioloudis, Petros J.

    2010-01-01

    Being able to dive and breathe underwater has been a challenge for thousands of years. In 1980, Fuji Systems of Tokyo developed a series of prototype gills for divers as a way of demonstrating just how good its membranes are. Even though gill technology has not yet reached the point where recipients can efficiently use implants to dive underwater,…

  2. Breathing metabolic simulator

    NASA Technical Reports Server (NTRS)

    Bartlett, R. G., Jr.; Hendricks, C. M.; Morison, W. B.

    1972-01-01

    A description is given of an automatic computer controlled second generation breathing metabolic simulator (BMS). The simulator is used for evaluating and testing respiratory diagnostic, monitoring, support, and resuscitation equipment. Any desired sequence of metabolic activities can be simulated on the device for up to 15 hours. The computer monitors test procedures and provides printouts of test results.

  3. Cardiovascular modeling and diagnostics

    SciTech Connect

    Kangas, L.J.; Keller, P.E.; Hashem, S.; Kouzes, R.T.

    1995-12-31

    In this paper, a novel approach to modeling and diagnosing the cardiovascular system is introduced. A model exhibits a subset of the dynamics of the cardiovascular behavior of an individual by using a recurrent artificial neural network. Potentially, a model will be incorporated into a cardiovascular diagnostic system. This approach is unique in that each cardiovascular model is developed from physiological measurements of an individual. Any differences between the modeled variables and the variables of an individual at a given time are used for diagnosis. This approach also exploits sensor fusion to optimize the utilization of biomedical sensors. The advantage of sensor fusion has been demonstrated in applications including control and diagnostics of mechanical and chemical processes.

  4. The Global Cardiovascular Risk Transition: Associations of Four Metabolic Risk Factors with Macroeconomic Variables in 1980 and 2008

    PubMed Central

    Danaei, Goodarz; Singh, Gitanjali M; Paciorek, Christopher J; Lin, John K; Cowan, Melanie J; Finucane, Mariel M; Farzadfar, Farshad; Stevens, Gretchen A; Riley, Leanne M; Lu, Yuan; Rao, Mayuree; Ezzati, Majid

    2014-01-01

    Background It is commonly assumed that globally CVD risk factors are associated with affluence and Westernization. We investigated the associations of body mass index (BMI), fasting plasma glucose (FPG), systolic blood pressure (SBP), and serum total cholesterol (TC) with national income, Western diet, and (for BMI) urbanization in 1980 and 2008. Methods and Results Country-level risk factor estimates for 199 countries between 1980 and 2008 were from a previous systematic analysis of population-based data. We analyzed the associations between risk factors and natural logarithm of per-capita GDP [Ln(GDP)], a measure of Western diet, and (for BMI) percent population living in urban areas. In 1980, there was a positive association between national income and population mean BMI, SBP, and TC. By 2008, the slope of the association between Ln(GDP) and SBP became negative for women and zero for men. TC was associated with national income and Western diet throughout the period. In 1980, BMI rose with per-capita GDP and then flattened at about Int$7000; by 2008, the relationship resembled an inverted-U for women, peaking at middle income levels. BMI had a positive relationship with percent urban population in both 1980 and 2008. FPG had weaker associations with these country macro characteristics, but was positively associated with BMI. Conclusions The changing associations of metabolic risk factors with macroeconomic variables indicate that there will be a global pandemic of hyperglycemia and diabetes, together with high blood pressure in low income countries, unless effective lifestyle, and pharmacological interventions are implemented. PMID:23481623

  5. Decompression sickness following breath-hold diving.

    PubMed

    Schipke, J D; Gams, E; Kallweit, Oliver

    2006-01-01

    Despite convincing evidence of a relationship between breath-hold diving and decompression sickness (DCS), the causal connection is only slowly being accepted. Only the more recent textbooks have acknowledged the risks of repetitive breath-hold diving. We compare four groups of breath-hold divers: (1) Japanese and Korean amas and other divers from the Pacific area, (2) instructors at naval training facilities, (3) spear fishers, and (4) free-dive athletes. While the number of amas is likely decreasing, and Scandinavian Navy training facilities recorded only a few accidents, the number of spear fishers suffering accidents is on the rise, in particular during championships or using scooters. Finally, national and international associations (e.g., International Association of Free Drives [IAFD] or Association Internationale pour Le Developpment De L'Apnee [AIDA]) promote free-diving championships including deep diving categories such as constant weight, variable weight, and no limit. A number of free-diving athletes, training for or participating in competitions, are increasingly accident prone as the world record is presently set at a depth of 171 m. This review presents data found after searching Medline and ISI Web of Science and using appropriate Internet search engines (e.g., Google). We report some 90 cases in which DCS occurred after repetitive breath-hold dives. Even today, the risk of suffering from DCS after repetitive breath-hold diving is often not acknowledged. We strongly suggest that breath-hold divers and their advisors and physicians be made aware of the possibility of DCS and of the appropriate therapeutic measures to be taken when DCS is suspected. Because the risk of suffering from DCS increases depending on depth, bottom time, rate of ascent, and duration of surface intervals, some approaches to assess the risks are presented. Regrettably, none of these approaches is widely accepted. We propose therefore the development of easily manageable

  6. The indoor air we breathe.

    PubMed Central

    Oliver, L C; Shackleton, B W

    1998-01-01

    Increasingly recognized as a potential public health problem since the outbreak of Legionnaire's disease in Philadelphia in 1976, polluted indoor air has been associated with health problems that include asthma, sick building syndrome, multiple chemical sensitivity, and hypersensitivity pneumonitis. Symptoms are often nonspecific and include headache, eye and throat irritation, chest tightness and shortness of breath, and fatigue. Air-borne contaminants include commonly used chemicals, vehicular exhaust, microbial organisms, fibrous glass particles, and dust. Identified causes include defective building design and construction, aging of buildings and their ventilation systems, poor climate control, inattention to building maintenance. A major contributory factor is the explosion in the use of chemicals in building construction and furnishing materials over the past four decades. Organizational issues and psychological variables often contribute to the problem and hinder its resolution. This article describes the health problems related to poor indoor air quality and offers solutions. Images p398-a p399-a PMID:9769764

  7. The indoor air we breathe.

    PubMed

    Oliver, L C; Shackleton, B W

    1998-01-01

    Increasingly recognized as a potential public health problem since the outbreak of Legionnaire's disease in Philadelphia in 1976, polluted indoor air has been associated with health problems that include asthma, sick building syndrome, multiple chemical sensitivity, and hypersensitivity pneumonitis. Symptoms are often nonspecific and include headache, eye and throat irritation, chest tightness and shortness of breath, and fatigue. Air-borne contaminants include commonly used chemicals, vehicular exhaust, microbial organisms, fibrous glass particles, and dust. Identified causes include defective building design and construction, aging of buildings and their ventilation systems, poor climate control, inattention to building maintenance. A major contributory factor is the explosion in the use of chemicals in building construction and furnishing materials over the past four decades. Organizational issues and psychological variables often contribute to the problem and hinder its resolution. This article describes the health problems related to poor indoor air quality and offers solutions.

  8. Removal and seasonal variability of selected analgesics/anti-inflammatory, anti-hypertensive/cardiovascular pharmaceuticals and UV filters in wastewater treatment plant.

    PubMed

    Golovko, Oksana; Kumar, Vimal; Fedorova, Ganna; Randak, Tomas; Grabic, Roman

    2014-06-01

    Seasonal removal efficiency of 16 pharmaceuticals and personal care products was monitored in a wastewater treatment plant in České Budějovice, Czech Republic, over a period of 1 year (total amount of samples, n = 272). The studied compounds included four UV filters, three analgesics/anti-inflammatory drugs and nine anti-hypertensive/cardiovascular drugs. In most cases, elimination of the substances was incomplete, and overall removal rates varied strongly from -38 to 100%. Therefore, it was difficult to establish a general trend for each therapeutic group. Based on the removal efficiencies (REs) over the year, three groups of target compounds were observed. A few compounds (benzophenon-1, valsartan, isradipine and furosemide) were not fully removed, but their REs were greater than 50%. The second group of analytes, consisting of 2-phenylbenzimidazole-5-sulfonic acid, tramadol, sotalol, metoprolol, atenolol and diclofenac, showed a very low RE (lower than 50%). The third group of compounds showed extremely variable RE (benzophenon-3 and benzophenon-4, codeine, verapamil, diltiazem and bisoprolol). There were significant seasonal trends in the observed REs, with reduced efficiencies in colder months.

  9. Study of time reversibility/irreversibility of cardiovascular data: theoretical results and application to laser Doppler flowmetry and heart rate variability signals

    NASA Astrophysics Data System (ADS)

    Humeau-Heurtier, Anne; Mahé, Guillaume; Chapeau-Blondeau, François; Rousseau, David; Abraham, Pierre

    2012-07-01

    Time irreversibility can be qualitatively defined as the degree of a signal for temporal asymmetry. Recently, a time irreversibility characterization method based on entropies of positive and negative increments has been proposed for experimental signals and applied to heart rate variability (HRV) data (central cardiovascular system (CVS)). The results led to interesting information as a time asymmetry index was found different for young subjects and elderly people or heart disease patients. Nevertheless, similar analyses have not yet been conducted on laser Doppler flowmetry (LDF) signals (peripheral CVS). We first propose to further investigate the above-mentioned characterization method. Then, LDF signals, LDF signals reduced to samples acquired during ECG R peaks (LDF_RECG signals) and HRV recorded simultaneously in healthy subjects are processed. Entropies of positive and negative increments for LDF signals show a nonmonotonic pattern: oscillations—more or less pronounced, depending on subjects—are found with a period matching the one of cardiac activity. However, such oscillations are not found with LDF_RECG nor with HRV. Moreover, the asymmetry index for LDF is markedly different from the ones of LDF_RECG and HRV. The cardiac activity may therefore play a dominant role in the time irreversibility properties of LDF signals.

  10. Increased Cardio-Respiratory Coupling Evoked by Slow Deep Breathing Can Persist in Normal Humans

    PubMed Central

    Dick, Thomas E.; Mims, Joseph R.; Hsieh, Yee-Hsee; Morris, Kendall F.; Wehrwein, Erica A.

    2014-01-01

    Slow deep breathing (SDB) has a therapeutic effect on autonomic tone. Our previous studies suggested that coupling of the cardiovascular to the respiratory system mediates plasticity expressed in sympathetic nerve activity. We hypothesized that SDB evokes short-term plasticity of cardiorespiratory coupling (CRC). We analyzed respiratory frequency (fr), heart rate and its variability (HR&HRV), the power spectral density (PSD) of blood pressure (BP) and the ventilatory pattern before, during, and after a 20-min epoch of SDB. During SDB, CRC and the relative PSD of BP at fr increased; mean arterial pressure decreased; but HR varied; increasing (n=3), or decreasing (n=2) or remaining the same (n=5). After SDB, short-term plasticity was not apparent for the group but for individuals differences existed between baseline and recovery periods. We conclude that a repeated practice, like pranayama, may strengthen CRC and evoke short-term plasticity effectively in a subset of individuals. PMID:25266396

  11. Emergency Response Breathing Apparatus

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Aerospace Design & Development, Inc.'s (ADD's) SCAMP was developed under an SBIR contract through Kennedy Space Center. SCAMP stands for Supercritical Air Mobility Pack. The technology came from the life support fuel cell support systems used for the Apollo and Space Shuttle programs. It uses supercritical cryogenic air and is able to function in microgravity environments. SCAMP's self-contained breathing apparatus(SCBA) systems are also ground-based and can provide twice as much air than traditional SCBA's due to its high-density capacity. The SCAMP system was designed for use in launch pad emergency rescues. ADD also developed a protective suit for use with SCAMP that is smaller and lighter system than the old ones. ADD's SCAMP allows for body cooling and breathing from the supercritical cryogenic air, requiring no extra systems. The improvement over the traditional SCBA allows for a reduction of injuries, such as heat stress, and makes it easier for rescuers to save lives.

  12. [TMJ, eating and breathing].

    PubMed

    Cheynet, F

    2016-09-01

    The study of the relationship between temporomandibular joints (TMJ), mastication and ventilation and the involvement of these two functions in the genesis of primary Temporomandibular Disorders (TMD) and in some dentofacial deformities, was initiated in France, more than 30years, by Professor Raymond Gola. Once criticized the weakness of the scientific literature in this domain, the originality of the TMJ within the masticatory system is recalled with its huge adaptation potential to very different biomechanical constraints according to the age and masticatory activities during the day. But the biomechanics of the masticatory system does not stop at night and the positions of the mandible and head during sleep should be studied carefully. In case of nocturnal mouth breathing with open mouth, the predominant sleeping position (generating small but long-term strengths) may be deleterious to the condyle-disc complex, to the surrounding muscles and the occlusal relationships. Some condyle-disc displacements and asymmetric malocclusions occur in this long portion of life what sleep, especially as oral breathing leads to a lot of dysfunctions (low position of the tongue, labio-lingual dysfunctions, exacerbation of bruxism sleep…). The aim of this work was to share our multidisciplinary experience of the biomechanical consequences of the nocturnal mouth breathing on the face involving orthodontists, maxillofacial surgeons, ENT, allergists, speech therapists, physiotherapists and radiologists.

  13. [TMJ, eating and breathing].

    PubMed

    Cheynet, F

    2016-09-01

    The study of the relationship between temporomandibular joints (TMJ), mastication and ventilation and the involvement of these two functions in the genesis of primary Temporomandibular Disorders (TMD) and in some dentofacial deformities, was initiated in France, more than 30years, by Professor Raymond Gola. Once criticized the weakness of the scientific literature in this domain, the originality of the TMJ within the masticatory system is recalled with its huge adaptation potential to very different biomechanical constraints according to the age and masticatory activities during the day. But the biomechanics of the masticatory system does not stop at night and the positions of the mandible and head during sleep should be studied carefully. In case of nocturnal mouth breathing with open mouth, the predominant sleeping position (generating small but long-term strengths) may be deleterious to the condyle-disc complex, to the surrounding muscles and the occlusal relationships. Some condyle-disc displacements and asymmetric malocclusions occur in this long portion of life what sleep, especially as oral breathing leads to a lot of dysfunctions (low position of the tongue, labio-lingual dysfunctions, exacerbation of bruxism sleep…). The aim of this work was to share our multidisciplinary experience of the biomechanical consequences of the nocturnal mouth breathing on the face involving orthodontists, maxillofacial surgeons, ENT, allergists, speech therapists, physiotherapists and radiologists. PMID:27554491

  14. Understanding the rhythm of breathing: so near yet so far

    PubMed Central

    Feldman, Jack L.; Del Negro, Christopher A.; Gray, Paul A.

    2013-01-01

    Understanding the mechanisms leading from DNA to molecules to neurons to networks to behavior is a major goal for neuroscience, but largely out of reach for many fundamental and interesting behaviors. The neural control of breathing may be a rare exception, presenting a unique opportunity to understand how the nervous system functions normally, how it balances inherent robustness with a highly regulated lability, how it adapts to rapidly and slowly changing conditions, and how particular dysfunctions result in disease. Why can we assert this? First and foremost, the functions of breathing are clearly definable, starting with its regulatory job of maintaining blood (and brain) O2, CO2 and pH; failure is not an option. Breathing is also an essential component of many vocal and emotive behaviors including, e.g., crying, laughing, singing, and sniffing, and must be coordinated with such vital behaviors as suckling and swallowing, even at birth. Second, the regulated variables, O2, CO2 and pH (and temperature in non-primate mammals), are continuous and are readily and precisely quantifiable, as is ventilation itself along with the underlying rhythmic motor activity, i.e., respiratory muscle EMGs. Third, we breathe all the time, except for short breaks as during breath-holding (which can be especially long in diving or hibernating mammals) or sleep apnea. Mammals (including humans) breathe in all behavioral states, e.g., sleep-wake, rest, exercise, panic, or fear, during anesthesia and even following decerebration. Moreover, essential aspects of the neural mechanisms driving breathing, including rhythmicity, are present at levels of reduction down to a medullary slice. Fourth, the relevant circuits exhibit a remarkable combination of extraordinary reliability, starting ex utero with the first air breath – intermittent breathing movements actually start in utero during the third trimester – and continuing for as many as ~109 breaths, as well as considerable lability

  15. EFFECT OF BODY SIZE ON BREATHING PATTERN AND FINE PARTICLE DEPOSITION IN CHILDREN

    EPA Science Inventory

    Inter-child variability in breathing patterns may contribute to variability in fine particle, lung deposition and morbidity in children associated with those particles. Fractional deposition (DF) of fine particles (2um monodisperse, carnauba wax particles) was measured in healthy...

  16. Symbolic dynamics of respiratory cycle related sleep EEG in children with sleep disordered breathing.

    PubMed

    Immanuel, Sarah A; Kohler, Mark; Kabir, Muammar M; Saint, David A; Baumert, Mathias

    2014-01-01

    Childhood sleep disordered breathing (SDB) is characterized by an increased work of breathing, restless night sleep and excessive daytime sleepiness and has been associated with cognitive impairment, behavioral disturbances and early cardiovascular changes. Compared to normal controls, children with SDB have elevated arousal thresholds and their sleep EEG may elicit cortical activation associated with arousals but often too subtle to be visually scored. The aim of this study was to assess EEG complexity throughout the respiratory cycle based on symbolic dynamics in children with SDB (n=40) and matched healthy controls. EEG amplitude values were symbolized based on the quartiles of their distribution and words of length 3 were formed and classed into 4 types based on their patterns. Children with SDB showed less complex EEG dynamics in non-REM sleep that was unrelated to the respiratory phase. In REM sleep normal children showed a respiratory phase-related reduction in EEG variability during the expiratory phase compared to inspiration, which was not apparent in children with SDB. In conclusion, respiratory cycle related EEG dynamics are altered in children with SDB during REM sleep and indicate changes in cortical activity.

  17. Breath-by-breath measurement of particle deposition in the lung of spontaneously breathing rats.

    PubMed

    Karrasch, S; Eder, G; Bolle, I; Tsuda, A; Schulz, H

    2009-10-01

    A number of deposition models for humans, as well as experimental animals, have been described. However, no breath-by-breath deposition measurement in rats has been reported to date. The objective of this study is to determine lung deposition of micrometer-sized particles as a function of breathing parameters in the adult rat lung. A new aerosol photometry system was designed to measure deposition of nonhygroscopic, 2-mum sebacate particles in anesthetized, intubated, and spontaneously breathing 90-day-old Wistar-Kyoto rats placed in a size-adjusted body plethysmograph box. Instrumental dead space of the system was minimized down to 310 microl (i.e., approximately 20% of respiratory dead space). The system allows continuous monitoring of particle concentration in the respired volume. Breathing parameters, such as respiratory rate (f), tidal volume (Vt), as well as inspiration/expiration times, were also monitored at different levels of anesthesia. The results showed that Vt typically varied between 1.5 and 4.0 ml for regular breathing and between 4.0 and 10.0 ml for single-sigh breaths; f ranged from 40 to 200 breaths/min. Corresponding deposition values varied between 5 and 50%, depending on breath-by-breath breathing patterns. The best fit of deposition (D) was achieved by a bilinear function of Vt and f and found to be D = 11.0 - 0.09.f + 3.75.Vt. We conclude that our approach provides more realistic conditions for the measurement of deposition than conventional models using ventilated animals and allows us to analyze the correlation between breath-specific deposition and spontaneous breathing patterns.

  18. Predictive Value of Beat-to-Beat QT Variability Index across the Continuum of Left Ventricular Dysfunction: Competing Risks of Non-cardiac or Cardiovascular Death, and Sudden or Non-Sudden Cardiac Death

    PubMed Central

    Tereshchenko, Larisa G.; Cygankiewicz, Iwona; McNitt, Scott; Vazquez, Rafael; Bayes-Genis, Antoni; Han, Lichy; Sur, Sanjoli; Couderc, Jean-Philippe; Berger, Ronald D.; de Luna, Antoni Bayes; Zareba, Wojciech

    2012-01-01

    Background The goal of this study was to determine the predictive value of beat-to-beat QT variability in heart failure (HF) patients across the continuum of left ventricular dysfunction. Methods and Results Beat-to-beat QT variability index (QTVI), heart rate variance (LogHRV), normalized QT variance (QTVN), and coherence between heart rate variability and QT variability have been measured at rest during sinus rhythm in 533 participants of the Muerte Subita en Insuficiencia Cardiaca (MUSIC) HF study (mean age 63.1±11.7; males 70.6%; LVEF >35% in 254 [48%]) and in 181 healthy participants from the Intercity Digital Electrocardiogram Alliance (IDEAL) database. During a median of 3.7 years of follow-up, 116 patients died, 52 from sudden cardiac death (SCD). In multivariate competing risk analyses, the highest QTVI quartile was associated with cardiovascular death [hazard ratio (HR) 1.67(95%CI 1.14-2.47), P=0.009] and in particular with non-sudden cardiac death [HR 2.91(1.69-5.01), P<0.001]. Elevated QTVI separated 97.5% of healthy individuals from subjects at risk for cardiovascular [HR 1.57(1.04-2.35), P=0.031], and non-sudden cardiac death in multivariate competing risk model [HR 2.58(1.13-3.78), P=0.001]. No interaction between QTVI and LVEF was found. QTVI predicted neither non-cardiac death (P=0.546) nor SCD (P=0.945). Decreased heart rate variability (HRV) rather than increased QT variability was the reason for increased QTVI in this study. Conclusions Increased QTVI due to depressed HRV predicts cardiovascular mortality and non-sudden cardiac death, but neither SCD nor excracardiac mortality in HF across the continuum of left ventricular dysfunction. Abnormally augmented QTVI separates 97.5% of healthy individuals from HF patients at risk. PMID:22730411

  19. Probing plasmonic breathing modes optically

    SciTech Connect

    Krug, Markus K. Reisecker, Michael; Hohenau, Andreas; Ditlbacher, Harald; Trügler, Andreas; Hohenester, Ulrich; Krenn, Joachim R.

    2014-10-27

    The confinement of surface plasmon modes in flat nanoparticles gives rise to plasmonic breathing modes. With a vanishing net dipole moment, breathing modes do not radiate, i.e., they are optically dark. Having thus escaped optical detection, breathing modes were only recently revealed in silver nanodisks with electron energy loss spectroscopy in an electron microscope. We show that for disk diameters >200 nm, retardation induced by oblique optical illumination relaxes the optically dark character. This makes breathing modes and thus the full plasmonic mode spectrum accessible to optical spectroscopy. The experimental spectroscopy data are in excellent agreement with numerical simulations.

  20. Cardiovascular Deconditioning

    NASA Technical Reports Server (NTRS)

    Charles, John B.; Fritsch-Yelle, Janice M.; Whitson, Peggy A.; Wood, Margie L.; Brown, Troy E.; Fortner, G. William

    1999-01-01

    Spaceflight causes adaptive changes in cardiovascular function that may deleteriously affect crew health and safety. Over the last three decades, symptoms of cardiovascular changes have ranged from postflight orthostatic tachycardia and decreased exercise capacity to serious cardiac rhythm disturbances during extravehicular activities (EVA). The most documented symptom of cardiovascular dysfunction, postflight orthostatic intolerance, has affected a significant percentage of U.S. Space Shuttle astronauts. Problems of cardiovascular dysfunction associated with spaceflight are a concern to NASA. This has been particularly true during Shuttle flights where the primary concern is the crew's physical health, including the pilot's ability to land the Orbiter, and the crew's ability to quickly egress and move to safety should a dangerous condition arise. The study of astronauts during Shuttle activities is inherently more difficult than most human research. Consequently, sample sizes have been small and results have lacked consistency. Before the Extended Duration Orbiter Medical Project (EDOMP), there was a lack of normative data on changes in cardiovascular parameters during and after spaceflight. The EDOMP for the first time allowed studies on a large enough number of subjects to overcome some of these problems. There were three primary goals of the Cardiovascular EDOMP studies. The first was to establish, through descriptive studies, a normative data base of cardiovascular changes attributable to spaceflight. The second goal was to determine mechanisms of cardiovascular changes resulting from spaceflight (particularly orthostatic hypotension and cardiac rhythm disturbances). The third was to evaluate possible countermeasures. The Cardiovascular EDOMP studies involved parallel descriptive, mechanistic, and countermeasure evaluations.

  1. The effect of attentional load on the breathing pattern in children.

    PubMed

    Denot-Ledunois, S; Vardon, G; Perruchet, P; Gallego, J

    1998-06-01

    Experiments designed to establish the effects of video games on breathing patterns have led to contradictory results. Several authors reported that video games tended to increase breathing frequency (i.e. to reduce breath duration), whereas others reported the opposite. We postulated that video games contain different psychophysiological components which may have opposite effects on breathing pattern. On the one hand, arousal and emotion may tend to stimulate breathing. On the other, focusing attention on the game may prompt subject to inhibit any movement--including breathing--which might be a potential nuisance variable. The aim of this study was to assess the specific effects of the attentional load in an experimental environment characterized by its low emotional impact. We measured breathing variables, cardiac frequency and cortisol levels in 10 healthy children (mean age = 9.2 +/- 1.5 years) who were familiar with the environment, the experimenter and the video game. Breath duration rose significantly, from 2.56 to 3.16 s, as a function of game difficulty. Cortisol levels, heart rate and the thoracic contribution to breathing displayed no significant changes. Taken together, these data suggest that focusing attention on the game tended to inhibit breathing and that previous contradictory reports in this respect were due to the confounding effects of emotion. PMID:9641244

  2. [Analysis of cardiorespiratory coupling in athletes and non-athletes at paced rate of breathing].

    PubMed

    Trubachev, V V; Gorbunov, A V; Trubacheva, V S; Nemtseva, M S; Ogorodnikova, M S

    2015-02-01

    The aims of the work were the study of cardiorespiratory coupling by method of paced breathing and the analysis of heart rate variability in men. Heart rhythm of 14 athletes and 12 non-athletes, 21 ± 1.4 years old, was registered in 3 minute sessions during spontaneous and paced breathing 14, 10, 9, 8, 7, 6, 5, 4 times/minute. The subjects were following breathing rate from a display. Initial heart rate being more slow in athletes (p < 0.05) was retained during episodes of controlled breathing. The power of FFT spectra peaks of RR-intervals was growing quasilinearly during reduction of breathing rate, reaching its peak value at 5-4 breaths/minute in athletes. More pronounced modulations of RR intervals were observed in HF spectral band (p < 0.05) of athletes breathing 14-10 times/minute compared to non-athletes. The power of LF band of the spectrum in athletes breathing 8-4 times/minute was 2 times higher: variability of RR-intervals "shrinked" accordingly to paced breathing rate. The dominant role in slow oscillations of heart rate manifested by paced respirations with involvement of vagus baroreflex afferentations of lungs and chest is hypothesized to be the consequence of breathing under attentional control.

  3. Sleep-disordered breathing and stroke.

    PubMed

    Ali, Latisha K; Avidan, Alon Y

    2008-01-01

    Sleep and stroke have an important and fascinating interaction. Patients with sleep-disordered breathing present with cardiovascular heart disease, cognitive decline, and increased risk of stroke. Stroke adversely affects sleep and factors such as prolonged immobilization, chronic pain, nocturnal hypoxia, and depression, which can also adversely impact sleep quality. Obstructive sleep apnea (OSA), one of the most common and serious sleep disturbances, manifests itself in almost 50% of all stroke patients. Sleep apnea patients who experience a stroke may be at a greater impairment in their rehabilitation potential and have increased risk of secondary stroke and mortality. Given these factors, the practicing neurologist should possess the skills to appropriately recognize, rapidly diagnose, and properly manage stroke patients with OSA.

  4. Patient's breath controls comfort devices

    NASA Technical Reports Server (NTRS)

    Schrader, M.; Carpenter, B.; Nichols, C. D.

    1972-01-01

    Patient assist system for totally disabled persons was developed which permits a person, so paralyzed as to be unable to move, to activate by breathing, a call system to summon assistance, turn the page of a book, ajust his bed, or do any one of a number of other things. System consists of patient assist control and breath actuated switch.

  5. BREATHE to Understand©

    ERIC Educational Resources Information Center

    Swisa, Maxine

    2015-01-01

    BREATHE is an acronym for Breathe, Reflect, Empathize, Accept, Thank, Hearten, Engage. The addition of Understand allows for a holistic approach to living a healthy and balanced life both inside and outside the classroom. This paper took form as a result of my personal, spiritual journey, as well as my teaching practice. I noticed that the…

  6. Yoga breathing, meditation, and longevity.

    PubMed

    Brown, Richard P; Gerbarg, Patricia L

    2009-08-01

    Yoga breathing is an important part of health and spiritual practices in Indo-Tibetan traditions. Considered fundamental for the development of physical well-being, meditation, awareness, and enlightenment, it is both a form of meditation in itself and a preparation for deep meditation. Yoga breathing (pranayama) can rapidly bring the mind to the present moment and reduce stress. In this paper, we review data indicating how breath work can affect longevity mechanisms in some ways that overlap with meditation and in other ways that are different from, but that synergistically enhance, the effects of meditation. We also provide clinical evidence for the use of yoga breathing in the treatment of depression, anxiety, post-traumatic stress disorder, and for victims of mass disasters. By inducing stress resilience, breath work enables us to rapidly and compassionately relieve many forms of suffering.

  7. Rapid shallow breathing index

    PubMed Central

    Karthika, Manjush; Al Enezi, Farhan A.; Pillai, Lalitha V.; Arabi, Yaseen M.

    2016-01-01

    Predicting successful liberation of patients from mechanical ventilation has been a focus of interest to clinicians practicing in intensive care. Various weaning indices have been investigated to identify an optimal weaning window. Among them, the rapid shallow breathing index (RSBI) has gained wide use due to its simple technique and avoidance of calculation of complex pulmonary mechanics. Since its first description, several modifications have been suggested, such as the serial measurements and the rate of change of RSBI, to further improve its predictive value. The objective of this paper is to review the utility of RSBI in predicting weaning success. In addition, the use of RSBI in specific patient populations and the reported modifications of RSBI technique that attempt to improve the utility of RSBI are also reviewed. PMID:27512505

  8. Rapid shallow breathing index.

    PubMed

    Karthika, Manjush; Al Enezi, Farhan A; Pillai, Lalitha V; Arabi, Yaseen M

    2016-01-01

    Predicting successful liberation of patients from mechanical ventilation has been a focus of interest to clinicians practicing in intensive care. Various weaning indices have been investigated to identify an optimal weaning window. Among them, the rapid shallow breathing index (RSBI) has gained wide use due to its simple technique and avoidance of calculation of complex pulmonary mechanics. Since its first description, several modifications have been suggested, such as the serial measurements and the rate of change of RSBI, to further improve its predictive value. The objective of this paper is to review the utility of RSBI in predicting weaning success. In addition, the use of RSBI in specific patient populations and the reported modifications of RSBI technique that attempt to improve the utility of RSBI are also reviewed. PMID:27512505

  9. Breathing zone air sampler

    DOEpatents

    Tobin, John

    1989-01-01

    A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  10. Growth of breath figures

    NASA Astrophysics Data System (ADS)

    Beysens, D.; Knobler, C. M.

    1986-09-01

    Measurements are reported of the growth of breath figures, the patterns that form when a vapor is condensed onto a cold surface. Water vapor was condensed on glass slides and the pattern was studied by direct observation and light scattering as a function of the contact angle theta, flux F, degree of supersaturation ΔT, and time t. When theta=0°, a uniform layer forms whose thickness grows as t at constant F and ΔT. For theta=90°, droplets are formed; at constant F and T, the radius of an isolated droplet grows as t0.23, but, as a result of coalescences, the average droplet radius grows as t0.75. The droplet growth process is self-similar-coalescences simply rescale the distances and leave the basic droplet pattern unaltered.

  11. Models of Cheyne-Stokes respiration with cardiovascular pathologies.

    PubMed

    Dong, Fang; Langford, William F

    2008-10-01

    Cheyne-Stokes respiration (CSR) is a periodic breathing pattern, characterized by short intervals of very little or no breathing (apnea), each followed by an interval of very heavy breathing (hyperpnea). This work presents a new compartmental model of the human cardio-respiratory system, simulating the factors that determine the concentrations of carbon dioxide in the compartments of the cardiovascular system and the lungs. The parameter set on which a Hopf bifurcation gives birth to stable CSR oscillations has been determined. The model predicts that the onset of CSR oscillations may result from an increase in any of: ventilation-perfusion ratio, feedback control gain, transport delay, left heart volume, lung congestion, or cardiovascular efficiency. The model is employed to investigate the relationship between CSR and serious cardiovascular pathologies, such as congestive heart failure and encephalitis, as well as the effects of acclimatization to higher altitudes. In all cases, the model is consistent with medical observations.

  12. Breath Analysis in Pulmonary Arterial Hypertension

    PubMed Central

    Cikach, Frank S.; Tonelli, Adriano R.; Barnes, Jarrod; Paschke, Kelly; Newman, Jennie; Grove, David; Dababneh, Luma; Wang, Sihe

    2014-01-01

    Background: Pulmonary arterial hypertension (PAH) is a progressive and devastating condition characterized by vascular cell proliferation and is associated with several metabolic derangements. We hypothesized that metabolic derangements in PAH can be detected by measuring metabolic by-products in exhaled breath. Methods: We collected breath and blood samples from patients with PAH at the time of right-sided heart catheterization (n = 31) and from healthy control subjects (n = 34). Breath was analyzed by selected ion flow tube-mass spectrometry in predetermined training and validation cohorts. Results: Patients with PAH were 51.5 ± 14 years old, and 27 were women (85%). Control subjects were 38 ± 13 years old, and 22 were women (65%). Discriminant analysis in the training set identified three ion peaks (H3O+29+, NO+56+, and O2+98+) and the variable age that correctly classified 88.9% of the individuals. In an independent validation cohort, 82.8% of the individuals were classified correctly. The concentrations of the volatile organic compounds 2-propanol, acetaldehyde, ammonia, ethanol, pentane, 1-decene, 1-octene, and 2-nonene were different in patients with PAH compared with control subjects. Exhaled ammonia was higher in patients with PAH (median [interquartile range]: 94.7 parts per billion (ppb) [70-129 ppb] vs 60.9 ppb [46-77 ppb], P < .001) and was associated with right atrial pressure (ρ = 0.57, P < .001), mean pulmonary artery pressure (ρ = 0.43, P = .015), cardiac index by thermodilution (ρ = −0.39, P = .03), pulmonary vascular resistance (ρ = 0.40, P = .04), mixed venous oxygen (ρ = −0.59, P < .001), and right ventricular dilation (ρ = 0.42, P = .03). Conclusions: Breathprint is different between patients with PAH and healthy control subjects. Several specific compounds, including ammonia, were elevated in the breath of patients with PAH. Exhaled ammonia levels correlated with severity of disease. PMID:24091389

  13. Classification of Asthma Based on Nonlinear Analysis of Breathing Pattern

    PubMed Central

    Raoufy, Mohammad Reza; Ghafari, Tara; Darooei, Reza; Nazari, Milad; Mahdaviani, Seyed Alireza; Eslaminejad, Ali Reza; Almasnia, Mehdi; Gharibzadeh, Shahriar; Mani, Ali R.; Hajizadeh, Sohrab

    2016-01-01

    Normal human breathing exhibits complex variability in both respiratory rhythm and volume. Analyzing such nonlinear fluctuations may provide clinically relevant information in patients with complex illnesses such as asthma. We compared the cycle-by-cycle fluctuations of inter-breath interval (IBI) and lung volume (LV) among healthy volunteers and patients with various types of asthma. Continuous respiratory datasets were collected from forty age-matched men including 10 healthy volunteers, 10 patients with controlled atopic asthma, 10 patients with uncontrolled atopic asthma, and 10 patients with uncontrolled non-atopic asthma during 60 min spontaneous breathing. Complexity of breathing pattern was quantified by calculating detrended fluctuation analysis, largest Lyapunov exponents, sample entropy, and cross-sample entropy. The IBI as well as LV fluctuations showed decreased long-range correlation, increased regularity and reduced sensitivity to initial conditions in patients with asthma, particularly in uncontrolled state. Our results also showed a strong synchronization between the IBI and LV in patients with uncontrolled asthma. Receiver operating characteristic (ROC) curve analysis showed that nonlinear analysis of breathing pattern has a diagnostic value in asthma and can be used in differentiating uncontrolled from controlled and non-atopic from atopic asthma. We suggest that complexity analysis of breathing dynamics may represent a novel physiologic marker to facilitate diagnosis and management of patients with asthma. However, future studies are needed to increase the validity of the study and to improve these novel methods for better patient management. PMID:26824900

  14. Effects of expiratory flow resistance on inspiratory work of breathing.

    PubMed

    Banner, M J; Downs, J B; Kirby, R R; Smith, R A; Boysen, P G; Lampotang, S

    1988-04-01

    To minimize work of breathing, airway pressure should not fluctuate during spontaneous breathing with continuous positive airway pressure (CPAP). However, flow resistance in the inspiratory limb of the breathing circuit and an inadequate continuous gas flow rate result in airway pressure fluctuation and increased work of breathing. Flow resistance of the expiratory pressure/exhalation valve also directly affects the level of airway pressure during spontaneous inhalation with CPAP (the greater the resistance of the valve, the greater the decrease in airway pressure and work of breathing). We compared this effect with three types of expiratory pressure valves: a threshold resistor with low resistance to flow, an inflatable balloon (mushroom) valve with moderate resistance to flow, and a variable-orifice flow resistor with a high resistance to flow. Work increased up to threefold with the balloon valve and more than tenfold with the flow resistor compared with the threshold resistor. To apply CPAP, expiratory pressure valves with low resistance to flow should be used to minimize fluctuations in airway pressure and, thus, in the work of spontaneous breathing. PMID:3280260

  15. A module of human peripheral blood mononuclear cell transcriptional network containing primitive and differentiation markers is related to specific cardiovascular health variables.

    PubMed

    Moldovan, Leni; Anghelina, Mirela; Kantor, Taylor; Jones, Desiree; Ramadan, Enass; Xiang, Yang; Huang, Kun; Kolipaka, Arunark; Malarkey, William; Ghasemzadeh, Nima; Mohler, Peter J; Quyyumi, Arshed; Moldovan, Nicanor I

    2014-01-01

    Peripheral blood mononuclear cells (PBMCs), including rare circulating stem and progenitor cells (CSPCs), have important yet poorly understood roles in the maintenance and repair of blood vessels and perfused organs. Our hypothesis was that the identities and functions of CSPCs in cardiovascular health could be ascertained by analyzing the patterns of their co-expressed markers in unselected PBMC samples. Because gene microarrays had failed to detect many stem cell-associated genes, we performed quantitative real-time PCR to measure the expression of 45 primitive and tissue differentiation markers in PBMCs from healthy and hypertensive human subjects. We compared these expression levels to the subjects' demographic and cardiovascular risk factors, including vascular stiffness. The tested marker genes were expressed in all of samples and organized in hierarchical transcriptional network modules, constructed by a bottom-up approach. An index of gene expression in one of these modules (metagene), defined as the average standardized relative copy numbers of 15 pluripotency and cardiovascular differentiation markers, was negatively correlated (all p<0.03) with age (R2 = -0.23), vascular stiffness (R2 = -0.24), and central aortic pressure (R2 = -0.19) and positively correlated with body mass index (R2 = 0.72, in women). The co-expression of three neovascular markers was validated at the single-cell level using mRNA in situ hybridization and immunocytochemistry. The overall gene expression in this cardiovascular module was reduced by 72±22% in the patients compared with controls. However, the compactness of both modules was increased in the patients' samples, which was reflected in reduced dispersion of their nodes' degrees of connectivity, suggesting a more primitive character of the patients' CSPCs. In conclusion, our results show that the relationship between CSPCs and vascular function is encoded in modules of the PBMCs transcriptional network

  16. Employing components-of-variance to evaluate forensic breath test instruments.

    PubMed

    Gullberg, Rod G

    2008-03-01

    The evaluation of breath alcohol instruments for forensic suitability generally includes the assessment of accuracy, precision, linearity, blood/breath comparisons, etc. Although relevant and important, these methods fail to evaluate other important analytical and biological components related to measurement variability. An experimental design comparing different instruments measuring replicate breath samples from several subjects is presented here. Three volunteers provided n = 10 breath samples into each of six different instruments within an 18 minute time period. Two-way analysis of variance was employed which quantified the between-instrument effect and the subject/instrument interaction. Variance contributions were also determined for the analytical and biological components. Significant between-instrument and subject/instrument interaction were observed. The biological component of total variance ranged from 56% to 98% among all subject instrument combinations. Such a design can help quantify the influence of and optimize breath sampling parameters that will reduce total measurement variability and enhance overall forensic confidence.

  17. Standardization of exhaled breath condensate (EBC) collection using a feedback regulated breathing pattern

    EPA Science Inventory

    Collection of exhaled breath condensate (EBC) fluid by cooling of expired breath is a potentially valuable approach for the detection of biomarkers associated with disease or exposure to xenobiotics. EBC is generally collected using unregulated breathing patterns, perceived to el...

  18. SU-E-J-62: Breath Hold for Left-Sided Breast Cancer: Visually Monitored Deep Inspiration Breath Hold Amplitude Evaluated Using Real-Time Position Management

    SciTech Connect

    Conroy, L; Quirk, S; Smith, WL; Yeung, R; Phan, T; Hudson, A

    2015-06-15

    Purpose: We used Real-Time Position Management (RPM) to evaluate breath hold amplitude and variability when gating with a visually monitored deep inspiration breath hold technique (VM-DIBH) with retrospective cine image chest wall position verification. Methods: Ten patients with left-sided breast cancer were treated using VM-DIBH. Respiratory motion was passively collected once weekly using RPM with the marker block positioned at the xiphoid process. Cine images on the tangent medial field were acquired on fractions with RPM monitoring for retrospective verification of chest wall position during breath hold. The amplitude and duration of all breath holds on which treatment beams were delivered were extracted from the RPM traces. Breath hold position coverage was evaluated for symmetric RPM gating windows from ± 1 to 5 mm centered on the average breath hold amplitude of the first measured fraction as a baseline. Results: The average (range) breath hold amplitude and duration was 18 mm (3–36 mm) and 19 s (7–34 s). The average (range) of amplitude standard deviation per patient over all breath holds was 2.7 mm (1.2–5.7 mm). With the largest allowable RPM gating window (± 5 mm), 4 of 10 VM-DIBH patients would have had ≥ 10% of their breath hold positions excluded by RPM. Cine verification of the chest wall position during the medial tangent field showed that the chest wall was greater than 5 mm from the baseline in only 1 out of 4 excluded patients. Cine images verify the chest wall/breast position only, whether this variation is acceptable in terms of heart sparing is a subject of future investigation. Conclusion: VM-DIBH allows for greater breath hold amplitude variability than using a 5 mm gating window with RPM, while maintaining chest wall positioning accuracy within 5 mm for the majority of patients.

  19. Calibrated variability of muscle sympathetic nerve activity during graded head-up tilt in humans and its link with noradrenaline data and cardiovascular rhythms.

    PubMed

    Marchi, Andrea; Bari, Vlasta; De Maria, Beatrice; Esler, Murray; Lambert, Elisabeth; Baumert, Mathias; Porta, Alberto

    2016-06-01

    Muscle sympathetic nerve activity (MSNA) variability is traditionally computed through a low-pass filtering procedure that requires normalization. We proposed a new beat-to-beat MSNA variability computation that preserves dimensionality typical of an integrated neural discharge (i.e., bursts per unit of time). The calibrated MSNA (cMSNA) variability technique is contrasted with the traditional uncalibrated MSNA (ucMSNA) version. The powers of cMSNA and ucMSNA variabilities in the low-frequency (LF, from 0.04 to 0.15 Hz) band were computed with those of the heart period (HP) of systolic and diastolic arterial pressure (SAP and DAP, respectively) in seven healthy subjects (age, 20-28 years; median, 22 years; 5 women) during a graded head-up tilt. Subjects were sequentially tilted at 0°, 20°, 30°, 40°, and 60° table inclinations. The LF powers of ucMSNA and HP variabilities were expressed in normalized units (LFnu), whereas all remaining spectral markers were expressed in absolute units. We found that 1) the LF power of cMSNA variability was positively correlated with tilt angle, whereas the LFnu power of the ucMSNA series was uncorrelated; 2) the LF power of cMSNA variability was correlated with LF powers of SAP and DAP, LFnu power of HP and noradrenaline concentration, whereas the relationship of the LFnu power of ucMSNA variability to LF powers of SAP and DAP was weaker and that to LFnu power of HP was absent; and 3) the stronger relationship of cMSNA variability to SAP and DAP spectral markers compared with the ucMSNA series was confirmed individually. The cMSNA variability appears to be more suitable in describing sympathetic control in humans than traditional ucMSNA variability. PMID:27009053

  20. Endothelial nitric oxide synthase gene intron 4 variable number tandem repeat polymorphism in β-thalassemia major: relation to cardiovascular complications.

    PubMed

    Tantawy, Azza A G; Adly, Amira A M; Ismail, Eman A; Aly, Shereen H

    2015-06-01

    Endothelial nitric oxide synthase (eNOS), an enzyme that generates nitric oxide, is a major determinant of endothelial function. Several eNOS gene polymorphisms have been reported as 'susceptibility genes' in various human diseases states, including cardiovascular, pulmonary and renal diseases. We studied the 27-base pair tandem repeat polymorphism in intron 4 of eNOS gene in 60 β-thalassemia major (β-TM) patients compared with 60 healthy controls and assessed its role in subclinical atherosclerosis and vascular complications. Patients were evaluated stressing on transfusion history, splenectomy, thrombotic events, echocardiography and carotid intima-media thickness (CIMT). Analysis of eNOS intron 4 gene polymorphism was performed by PCR. No significant difference was found between β-TM patients and controls with regard to the distribution of eNOS4 alleles or genotypes. The frequency of eNOS4a allele (aa and ab genotypes) was significantly higher in β-TM patients with pulmonary hypertension or cardiomyopathy. Logistic regression analysis revealed that eNOS4a allele was an independent risk factor for pulmonary hypertension in β-TM patients [odds ratio (OR) 2.2, 95% confidence interval (95% CI) 1.19-5.6; P < 0.001]. We suggest that eNOS intron 4 gene polymorphism is related to endothelial dysfunction and subclinical atherosclerosis and could be a possible genetic marker for prediction of increased susceptibility to cardiovascular complications.

  1. Endothelial nitric oxide synthase gene intron 4 variable number tandem repeat polymorphism in β-thalassemia major: relation to cardiovascular complications.

    PubMed

    Tantawy, Azza A G; Adly, Amira A M; Ismail, Eman A; Aly, Shereen H

    2015-06-01

    Endothelial nitric oxide synthase (eNOS), an enzyme that generates nitric oxide, is a major determinant of endothelial function. Several eNOS gene polymorphisms have been reported as 'susceptibility genes' in various human diseases states, including cardiovascular, pulmonary and renal diseases. We studied the 27-base pair tandem repeat polymorphism in intron 4 of eNOS gene in 60 β-thalassemia major (β-TM) patients compared with 60 healthy controls and assessed its role in subclinical atherosclerosis and vascular complications. Patients were evaluated stressing on transfusion history, splenectomy, thrombotic events, echocardiography and carotid intima-media thickness (CIMT). Analysis of eNOS intron 4 gene polymorphism was performed by PCR. No significant difference was found between β-TM patients and controls with regard to the distribution of eNOS4 alleles or genotypes. The frequency of eNOS4a allele (aa and ab genotypes) was significantly higher in β-TM patients with pulmonary hypertension or cardiomyopathy. Logistic regression analysis revealed that eNOS4a allele was an independent risk factor for pulmonary hypertension in β-TM patients [odds ratio (OR) 2.2, 95% confidence interval (95% CI) 1.19-5.6; P < 0.001]. We suggest that eNOS intron 4 gene polymorphism is related to endothelial dysfunction and subclinical atherosclerosis and could be a possible genetic marker for prediction of increased susceptibility to cardiovascular complications. PMID:25699607

  2. A Study of the Effects of Breath Management Instruction on the Breathing Mode, Knowledge of Breathing, and Performance Skills of College-Level Brass Players.

    ERIC Educational Resources Information Center

    Phillips, Kenneth H.; Sehmann, Karin Harfst

    1990-01-01

    Investigates the effectiveness of breathing instruction on the breath management, performance, and knowledge of breathing among college-level brass musicians. Finds that breathing instruction significantly improved the breath management and knowledge of the breathing for the experimental groups and the musical range of the trombone players in the…

  3. Mind-body relationships in elite apnea divers during breath holding: a study of autonomic responses to acute hypoxemia

    PubMed Central

    Laurino, Marco; Menicucci, Danilo; Mastorci, Francesca; Allegrini, Paolo; Piarulli, Andrea; Scilingo, Enzo P.; Bedini, Remo; Pingitore, Alessandro; Passera, Mirko; L'Abbate, Antonio; Gemignani, Angelo

    2011-01-01

    The mental control of ventilation with all associated phenomena, from relaxation to modulation of emotions, from cardiovascular to metabolic adaptations, constitutes a psychophysiological condition characterizing voluntary breath-holding (BH). BH induces several autonomic responses, involving both autonomic cardiovascular and cutaneous pathways, whose characterization is the main aim of this study. Electrocardiogram and skin conductance (SC) recordings were collected from 14 elite divers during three conditions: free breathing (FB), normoxic phase of BH (NPBH) and hypoxic phase of BH (HPBH). Thus, we compared a set of features describing signal dynamics between the three experimental conditions: from heart rate variability (HRV) features (in time and frequency-domains and by using nonlinear methods) to rate and shape of spontaneous SC responses (SCRs). The main result of the study rises by applying a Factor Analysis to the subset of features significantly changed in the two BH phases. Indeed, the Factor Analysis allowed to uncover the structure of latent factors which modeled the autonomic response: a factor describing the autonomic balance (AB), one the information increase rate (IIR), and a latter the central nervous system driver (CNSD). The BH did not disrupt the FB factorial structure, and only few features moved among factors. Factor Analysis indicates that during BH (1) only the SC described the emotional output, (2) the sympathetic tone on heart did not change, (3) the dynamics of interbeats intervals showed an increase of long-range correlation that anticipates the HPBH, followed by a drop to a random behavior. In conclusion, data show that the autonomic control on heart rate and SC are differentially modulated during BH, which could be related to a more pronounced effect on emotional control induced by the mental training to BH. PMID:22461774

  4. Breathing and Singing: Objective Characterization of Breathing Patterns in Classical Singers

    PubMed Central

    Salomoni, Sauro; van den Hoorn, Wolbert; Hodges, Paul

    2016-01-01

    Singing involves distinct respiratory kinematics (i.e. movements of rib cage and abdomen) to quiet breathing because of different demands on the respiratory system. Professional classical singers often advocate for the advantages of an active control of the abdomen on singing performance. This is presumed to prevent shortening of the diaphragm, elevate the rib cage, and thus promote efficient generation of subglottal pressure during phonation. However, few studies have investigated these patterns quantitatively and inter-subject variability has hindered the identification of stereotypical patterns of respiratory kinematics. Here, seven professional classical singers and four untrained individuals were assessed during quiet breathing, and when singing both a standard song and a piece of choice. Several parameters were extracted from respiratory kinematics and airflow, and principal component analysis was used to identify typical patterns of respiratory kinematics. No group differences were observed during quiet breathing. During singing, both groups adapted to rhythmical constraints with decreased time of inspiration and increased peak airflow. In contrast to untrained individuals, classical singers used greater percentage of abdominal contribution to lung volume during singing and greater asynchrony between movements of rib cage and abdomen. Classical singers substantially altered the coordination of rib cage and abdomen during singing from that used for quiet breathing. Despite variations between participants, principal component analysis revealed consistent pre-phonatory inward movements of the abdominal wall during singing. This contrasted with untrained individuals, who demonstrated synchronous respiratory movements during all tasks. The inward abdominal movements observed in classical singers elevates intra-abdominal pressure and may increase the length and the pressure-generating capacity of rib cage expiratory muscles for potential improvements in voice

  5. Stroke and sleep-disordered breathing: A relationship under construction.

    PubMed

    Parra, Olga; Arboix, Adrià

    2016-02-16

    The association between sleep-disordered breathing (SDB) and cardiovascular risk has been the focus of attention in recent years. Sleep disorders are emerging risk factors for cardiovascular disease and have been related to the whole spectrum of stroke, including transient ischemic attack, ischemic cerebral infarction and intracerebral haemorrhage. It has been shown that lacunar stroke or lacunar infarctions affecting the internal capsule or the protuberance are associated with a higher frequency of SDB. Acute stroke patients with associated SDB have a worse prognosis and a higher mortality as compared to patients with first-ever stroke without SDB. Preliminary studies provide evidence of the usefulness of treatment with continuous positive airway pressure when SDB is present in stroke patients. PMID:26881189

  6. Sleep-Disordered Breathing in the National Football League

    PubMed Central

    Rice, Thomas B.; Dunn, Reginald E.; Lincoln, Andrew E.; Tucker, Andrew M.; Vogel, Robert A.; Heyer, Robert A.; Yates, Anthony P.; Wilson, Peter W. F.; Pellmen, Elliot J.; Allen, Thomas W.; Newman, Anne B.; Strollo, Patrick J.

    2010-01-01

    Study Objectives: Prior studies have suggested that the prevalence of sleep disordered breathing (SDB) among players in the National Football League (NFL) is disproportionately high. SDB can increase cardiovascular disease risk and is correlated with hypertension. NFL players have a higher prevalence of hypertension, and we sought to determine the prevalence of SDB among players the NFL and the associations of SDB with anthropometric measures and cardiovascular risk factors. Design: Cross-sectional cohort study. Setting: NFL athletic training facilities from April to July 2007. Participants: A total of 137 active veteran players from 6 NFL teams. Measurements: This evaluation of SDB among players in the NFL used a single-channel, home-based, unattended, portable, sleep apnea monitor. Multiple domains of self-reported sleep were assessed. Weight, body mass index, body fat percentage, neck circumference, waist circumference, and waist-to-hip ratio, as well as blood pressure, cholesterol, and fasting glucose concentrations were measured. Results: The mean respiratory disturbance index was 4.7 (± 12), with a median (interquartile range) of 2 (1,4). The prevalence of at least mild SDB (RDI ≥ 5) was 19% (95% confidence interval, 12.8%-26.6%). Only 4.4% (95% confidence interval, 1.6%-9.2%) of participants had respiratory disturbance index of 15 or greater. Linemen and non-linemen were not different in their prevalence or severity of SDB. No single anthropometric measure was highly associated with SDB, and SDB was not well correlated with cardiovascular risk factors. Conclusions: The prevalence of SDB in active NFL players was modest, predominately mild, and positively associated with several measures of adiposity. SDB did not account for excess cardiovascular risk factors. Citation: Rice TB; Dunn RE; Lincoln AE; Tucker AM; Vogel RA; Heyer RA; Yates AP; Wilson PWF; Pellmen EJ; Allen TW; Newman AB; Strollo PJ. Sleep-disordered breathing in the National Football League

  7. Sigh-induced changes of breathing pattern in preterm infants

    PubMed Central

    Jost, Kerstin; Latzin, Philipp; Fouzas, Sotirios; Proietti, Elena; Delgado-Eckert, Edgar W; Frey, Urs; Schulzke, Sven M

    2015-01-01

    Sighs are thought to play an important role in control of breathing. It is unclear how sighs are triggered, and whether preterm birth and lung disease influence breathing pattern prior to and after a sigh in infants. To assess whether frequency, morphology, size, and short-term variability in tidal volume (VT) before, during, and after a sigh are influenced by gestational age at birth and lung disease (bronchopulmonary dysplasia, BPD) in former preterm infants and healthy term controls measured at equivalent postconceptional age (PCA). We performed tidal breathing measurements in 143 infants during quiet natural sleep at a mean (SD) PCA of 44.8 (1.3) weeks. A total of 233 sighs were analyzed using multilevel, multivariable regression. Sigh frequency in preterm infants increased with the degree of prematurity and severity of BPD, but was not different from that of term controls when normalized to respiratory rate. After a sigh, VT decreased remarkably in all infants (paired t-test: P < 0.001). There was no major effect of prematurity or BPD on various indices of sigh morphology and changes in VT prior to or after a sigh. Short-term variability in VT modestly increased with maturity at birth and infants with BPD showed an earlier return to baseline variability in VT following a sigh. In early infancy, sigh-induced changes in breathing pattern are moderately influenced by prematurity and BPD in preterm infants. The major determinants of sigh-related breathing pattern in these infants remain to be investigated, ideally using a longitudinal study design. PMID:26564066

  8. Breathing challenges in Rett Syndrome: Lessons learned from humans and animal models✩,✩✩

    PubMed Central

    Ramirez, Jan-Marino; Ward, Christopher Scott; Neul, Jeffrey Lorenz

    2013-01-01

    Breathing disturbances are a major challenge in Rett Syndrome (RTT). These disturbances are more pronounced during wakefulness; but irregular breathing occurs also during sleep. During the day patients can exhibit alternating bouts of hypoventilation and irregular hyperventilation. But there is significant individual variability in severity, onset, duration and type of breathing disturbances. Research in mouse models of RTT suggests that different areas in the ventrolateral medulla and pons give rise to different aspects of this breathing disorder. Pre-clinical experiments in mouse models that target different neuromodulatory and neurotransmitter receptors and MeCP2 function within glia cells can partly reverse breathing abnormalities. The success in animal models raises optimism that one day it will be possible to control or potentially cure the devastating symptoms also in human patients with RTT. PMID:23816600

  9. Submarines, Spacecraft, and Exhaled Breath

    EPA Science Inventory

    The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled b...

  10. Functional analysis and intervention for breath holding.

    PubMed

    Kern, L; Mauk, J E; Marder, T J; Mace, F C

    1995-01-01

    We conducted a functional analysis of breath-holding episodes in a 7-year-old girl with severe mental retardation and Cornelia-de-Lange syndrome. The results showed that breath holding served an operant function, primarily to gain access to attention. The intervention, consisting of extinction, scheduled attention, and use of a picture card communication system, resulted in decreased breath holding.

  11. Cardiovascular complications of respiratory diseases.

    PubMed

    Chowdhuri, Susmita; Crook, Errol D; Taylor, Herman A; Badr, M Safwan

    2007-11-01

    A major burden of morbidity and mortality due to respiratory diseases can be directly related to the cardiovascular (CV) complications of these disorders. Evidence from cross-sectional and longitudinal studies link reduced lung function and cardiovascular diseases. However, the underlying pathogenic mechanisms are unclear. Hypoxia-induced increased sympathetic activity, blood viscosity, or inflammation, among other factors, may mediate the underlying pathogenesis. In addition, sleep-disordered breathing (SDB) has been implicated by association in multiple CV diseases including hypertension, ischemic heart disease, congestive heart failure, arrhythmias, and stroke. However, the exact contribution of SDB, including obstructive and central sleep apneas, to the development of cardiovascular diseases is not fully understood. In this context, the contribution of the new large, prospective, Jackson Heart Study could be significant in that it is designed to answer several of these questions, specifically in the African American population. This review examines the current evidence that links both reduced lung function and SDB to CV diseases. PMID:18004091

  12. Theme and variations: amphibious air-breathing intertidal fishes.

    PubMed

    Martin, K L

    2014-03-01

    Over 70 species of intertidal fishes from 12 families breathe air while emerging from water. Amphibious intertidal fishes generally have no specialized air-breathing organ but rely on vascularized mucosae and cutaneous surfaces in air to exchange both oxygen and carbon dioxide. They differ from air-breathing freshwater fishes in morphology, physiology, ecology and behaviour. Air breathing and terrestrial activity are present to varying degrees in intertidal fish species, correlated with the tidal height of their habitat. The gradient of amphibious lifestyle includes passive remainers that stay in the intertidal zone as tides ebb, active emergers that deliberately leave water in response to poor aquatic conditions and highly mobile amphibious skipper fishes that may spend more time out of water than in it. Normal terrestrial activity is usually aerobic and metabolic rates in air and water are similar. Anaerobic metabolism may be employed during forced exercise or when exposed to aquatic hypoxia. Adaptations for amphibious life include reductions in gill surface area, increased reliance on the skin for respiration and ion exchange, high affinity of haemoglobin for oxygen and adjustments to ventilation and metabolism while in air. Intertidal fishes remain close to water and do not travel far terrestrially, and are unlikely to migrate or colonize new habitats at present, although in the past this may have happened. Many fish species spawn in the intertidal zone, including some that do not breathe air, as eggs and embryos that develop in the intertidal zone benefit from tidal air emergence. With air breathing, amphibious intertidal fishes survive in a variable habitat with minimal adjustments to existing structures. Closely related species in different microhabitats provide unique opportunities for comparative studies.

  13. The effects of sighing on the cardiovascular system

    PubMed Central

    Vaschillo, Evgeny G.; Vaschillo, Bronya; Buckman, Jennifer F.; Nguyen-Louie, Tam; Heiss, Sydney; Pandina, Robert J.; Bates, Marsha E.

    2015-01-01

    Elicitation of high-amplitude oscillations in the cardiovascular system may serve to dampen psychophysiological reactivity to emotional and cognitive loading. Prior work has used paced breathing to impose clinically valuable high-amplitude ~0.1Hz oscillations. In this study, we investigated whether rhythmical sighing could likewise produce high-amplitude cardiovascular oscillations in the very low frequency range (0.003–0.05Hz). ECG, respiration, skin conductance, and beat-to-beat blood pressure were collected in 24 healthy participants during baseline, 0.1Hz paced breathing, and 0.02Hz paced sighing (1 sigh every 50 seconds, with normal breathing interspersed). Results showed that each sigh elicited a strong, well-defined reaction in the cardiovascular system. This reaction did not habituate when participants repeatedly sighed for 8.5 minutes. The result was a high-amplitude 0.02Hz oscillation in multiple cardiovascular parameters. Thus, paced sighing is a reliable method for imposing very low frequency oscillations in the cardiovascular system, which has research and clinical implications that warrant further study. PMID:25720947

  14. The effects of sighing on the cardiovascular system.

    PubMed

    Vaschillo, Evgeny G; Vaschillo, Bronya; Buckman, Jennifer F; Nguyen-Louie, Tam; Heiss, Sydney; Pandina, Robert J; Bates, Marsha E

    2015-03-01

    Elicitation of high-amplitude oscillations in the cardiovascular system may serve to dampen psychophysiological reactivity to emotional and cognitive loading. Prior work has used paced breathing to impose clinically valuable high-amplitude ∼ 0.1 Hz oscillations. In this study, we investigated whether rhythmical sighing could likewise produce high-amplitude cardiovascular oscillations in the very low frequency range (0.003-0.05 Hz). ECG, respiration, skin conductance, and beat-to-beat blood pressure were collected in 24 healthy participants during baseline, 0.1 Hz paced breathing, and 0.02 Hz paced sighing (1 sigh every 50s, with normal breathing interspersed). Results showed that each sigh elicited a strong, well-defined reaction in the cardiovascular system. This reaction did not habituate when participants repeatedly sighed for 8.5 min. The result was a high-amplitude 0.02 Hz oscillation in multiple cardiovascular parameters. Thus, paced sighing is a reliable method for imposing very low frequency oscillations in the cardiovascular system, which has research and clinical implications that warrant further study.

  15. The experimental modification of sonorous breathing.

    PubMed Central

    Josephson, S C; Rosen, R C

    1980-01-01

    Loud snoring is a noxious habit and potential personal health risk. We are reporting the first experimental study of simple behavioral techniques for the modification of chronic snoring. Twenty-four volunteers participated in a repeated measures, randomized group design over 2 weeks of intervention and one-month follow-up. Treatment groups included a contingent-awakening and breathing retraining (self-control) condition. Both treatment groups were compared to a no-treatment control. Despite considerable intra-subject variability and the lack of an adequate attention-placebo control group, objective assessment indicated a substantial reduction in snoring amplitude and frequency in both treatment groups. Follow-up assessments further demonstrated maintenance of change. This study has implications for modification of sleep habit disorders and learning without awareness. PMID:7380759

  16. Monitoring breath during oral glucose tolerance tests.

    PubMed

    Ghimenti, S; Tabucchi, S; Lomonaco, T; Di Francesco, F; Fuoco, R; Onor, M; Lenzi, S; Trivella, M G

    2013-03-01

    The evolution of breath composition during oral glucose tolerance tests (OGTTs) was analysed by thermal desorption/gas chromatography/mass spectrometry in 16 subjects and correlated to blood glucose levels. The glucose tolerance tests classified five of the subjects as diabetics, eight as affected by impaired glucose tolerance and three as normoglycaemic. Acetone levels were generally higher in diabetics (average concentration values: diabetics, 300 ± 40 ppbv; impaired glucose tolerance, 350 ± 30 ppbv; normoglycaemic, 230 ± 20 ppbv) but the large inter-individual variability did not allow us to identify the three groups by this parameter alone. The exhalation of 3-hydroxy-butan-2-one and butane-2,3-dione, likely due to the metabolization of glucose by bacteria in the mouth, was also observed. Future work will involve the extension of the analyses to other volatile compounds by attempting to improve the level of discrimination between the various classes of subjects. PMID:23446273

  17. Drive mechanism for production of simulated human breath

    NASA Technical Reports Server (NTRS)

    Bartlett, R. G.; Hendricks, C. M.; Lambert, J. W.; Morison, W. B.

    1972-01-01

    Simulated breath drive mechanism was developed as subsystem to breathing metabolic simulator. Mechanism reproduces complete range of human breath rate, breath depth, and breath waveform, as well as independently controlled functional residual capacity. Mechanism was found capable of simulating various individual human breathing characteristics without any changes of parts.

  18. Inhaled today, not gone tomorrow: pharmacokinetics and environmental exposure of volatiles in exhaled breath.

    PubMed

    Beauchamp, J

    2011-09-01

    The chemical analysis of exhaled breath gas to assess state of health or identify disease biomarkers has gained growing interest in recent years, with advances in new technologies providing scientists and physicians with a powerful analytical arsenal with which to tackle pertinent issues. The application of these methods for pharmacokinetic studies, however, has received less attention despite its enormous potential in this field. For instance, breath gas analysis may be employed to characterize uptake and distribution within the body of exogenous volatile compounds, either from a pharmaceutical point of view, or in relation to environmental inhalation exposure. Both of these topics can benefit greatly from utilizing breath gas complementarily or as a surrogate to blood as an analytical medium, since breath sampling is non-invasive, inexhaustible, and is achievable with a frequency far exceeding that which is feasible for blood. However, because of the efficiency with which certain exogenous compounds are reflected in breath, this can also often be a significant source of confounding variables that require consideration in routine breath gas analyses. This paper provides an overview of the possibilities of breath gas analysis for pharmacokinetics and environmental exposure investigations and discusses the presence of exogenous compounds in standard breath analyses and their repercussions in terms of erroneous data interpretation.

  19. [Subclinical hypothyroidism and cardiovascular risk].

    PubMed

    López Rubio, María Antonia; Tárraga López, Pedro Juan; Rodríguez Montes, José Antonio; Frías López, María del Carmen; Solera Albero, Juan; Bermejo López, Pablo

    2015-05-01

    Objetivos: Valorar si el hipotiroidismo subclínico puede comportarse como un factor de riesgo cardiovascular o un modificador del mismo, identificando variables epidemiológicas y riesgo cardiovascular estimado en una muestra de sujetos diagnosticados en la provincia de Albacete. Método: Estudio observacional, descriptivo y transversal realizado en Albacete durante la primera quincena de enero de 2012 en pacientes de ambos géneros con hipotiroidismo subclínico. Se analizaron las siguientes variables: glucemia basal, colesterol total, colesterol HDL, colesterol LDL, triglicéridos, TSH, T4, peso, talla, I.M.C., tensión arterial, antecedentes de patología cardiovascular, factores de riesgo cardiovascular y riesgo cardiovascular estimado. Resultados: Se obtuvieron 326 pacientes, con predominio femenino (79,2 %), menores de 65 años en el 78% y sin factores de riesgo cardiovascular en el 48,61%. La prevalencia de los factores de riesgo cardiovascular identificados fué: tabaquismo (33,2%), diabetes mellitus (24,9%), hipertensión arterial (23,4%), alteraciones lipídicas (28,9%) y fibrilación auricular (4,9 %). No se encontró asociación entre hipotiroidismo subclínico y la mayoría de los parámetros del perfil lipídico que condicionan un perfil pro-aterogénico, salvo con la hipertrigliceridemia. Asimismo, tampoco se constató asociación con riesgo cardiovascular aumentado. Conclusiones: El perfil del paciente con hipotiroidismo subclínico es una mujer de mediana edad sin factores de riesgo cardiovascular en la mitad de casos. Se ha encontrado relación entre hipotiroidismo subclínico e hipertrigliceridemia, pero no con el resto de parámetros del perfil lipídico, otros factores de riesgo cardiovascular o con aumento de dicho riesgo. Sin embargo, un 25% de diabéticos y un 22% de no diabéticos están en situación de riesgo cardiovascular moderado-alto.

  20. Association between the rapid shallow breathing index and extubation success in patients with traumatic brain injury

    PubMed Central

    dos Reis, Helena França Correia; Almeida, Mônica Lajana Oliveira; da Silva, Mário Ferreira; Moreira, Julião Oliveira; Rocha, Mário de Seixas

    2013-01-01

    Objective To investigate the association between the rapid shallow breathing index and successful extubation in patients with traumatic brain injury. Methods This study was a prospective study conducted in patients with traumatic brain injury of both genders who underwent mechanical ventilation for at least two days and who passed a spontaneous breathing trial. The minute volume and respiratory rate were measured using a ventilometer, and the data were used to calculate the rapid shallow breathing index (respiratory rate/tidal volume). The dependent variable was the extubation outcome: reintubation after up to 48 hours (extubation failure) or not (extubation success). The independent variable was the rapid shallow breathing index measured after a successful spontaneous breathing trial. Results The sample comprised 119 individuals, including 111 (93.3%) males. The average age of the sample was 35.0±12.9 years old. The average duration of mechanical ventilation was 8.1±3.6 days. A total of 104 (87.4%) participants achieved successful extubation. No association was found between the rapid shallow breathing index and extubation success. Conclusion The rapid shallow breathing index was not associated with successful extubation in patients with traumatic brain injury. PMID:24213084

  1. Why are some studies of cardiovascular markers unreliable? The role of measurement variability and what an aspiring clinician scientist can do before it is too late.

    PubMed

    Shun-Shin, Matthew; Francis, Darrel P

    2012-01-01

    Cardiology research suffers from the scourge of unreliable results, despite honest conduct. Investigators' prior belief, compromised blinding, and scope for measurement variability are a fatally synergistic combination. Can we stop these threats ruining the results? First, clinical researchers must realize that healthy clinical practice (including intelligently integrating all available information) may be catastrophic to research. Second, experienced clinicians know that variability may necessitate remeasurement to obtain a clinically correct result but must learn that doing so in research can cause surprisingly severe distortions of correlations or differences between groups. For example, a "best-of-four" approach in comparing two 50-patient groups that are in reality identical, with a variable whose intraclass correlation is 0.8, easily generates highly significant P values. Clinicians may be habituated to poorly reproducible clinical measurements and falsely reassured by their effectiveness for group mean effects in blinded randomized controlled trials. We need a more critical approach to clinical tests if we care about evaluating individual patients reliably or want our research to be reliable. Simple steps shown here, addressed during study design, will increase the reliability of research-if considered by researchers or the juniors whom they nurture.

  2. Analysis of Exhaled Breath for Disease Detection

    NASA Astrophysics Data System (ADS)

    Amann, Anton; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Ligor, Tomasz; Jezierski, Tadeusz; Pleil, Joachim; Risby, Terence

    2014-06-01

    Breath analysis is a young field of research with great clinical potential. As a result of this interest, researchers have developed new analytical techniques that permit real-time analysis of exhaled breath with breath-to-breath resolution in addition to the conventional central laboratory methods using gas chromatography-mass spectrometry. Breath tests are based on endogenously produced volatiles, metabolites of ingested precursors, metabolites produced by bacteria in the gut or the airways, or volatiles appearing after environmental exposure. The composition of exhaled breath may contain valuable information for patients presenting with asthma, renal and liver diseases, lung cancer, chronic obstructive pulmonary disease, inflammatory lung disease, or metabolic disorders. In addition, oxidative stress status may be monitored via volatile products of lipid peroxidation. Measurement of enzyme activity provides phenotypic information important in personalized medicine, whereas breath measurements provide insight into perturbations of the human exposome and can be interpreted as preclinical signals of adverse outcome pathways.

  3. [Stahl, Leibniz, Hoffmann and breathing].

    PubMed

    Carvallo, Sarah

    2006-01-01

    At the beginning of the XVIII th century, Wilhelm Gottfried Leibniz and Friedrich Hoffmann criticize Georg Ernst Stahl's medical theory. They differenciate between unsound and true reasonings. Namely, they validate Stahl's definition of breath but extracting it from its animist basis and placing it in an epistemology obeying to the principle of sufficient reason and to the mechanical model. The stahlian discovery consists in understanding breath as a calorific ventilation against the ancient conception; the iatromechanists recognize its accuracy, but they try then to transpose it to a mechanical model of ventilation. Using it in a different epistemological context implies that they analyze the idea of discovery "true" in its contents, but "wrong" in its hypothesis. It impels to examine the epistemology of medical knowledge, as science and therapeutics, and in its links with the other scientific theories. Thus, if Leibniz as philosopher and Hoffmann as doctor consider Stahl's animism so important, it is because its discoveries question the fundamental principles of medicine.

  4. Self-contained breathing apparatus

    NASA Technical Reports Server (NTRS)

    Sullivan, J. L.; Giorgini, E. A.; Simmonds, M. R. (Inventor)

    1976-01-01

    A self-contained breathing apparatus with automatic redundant fluid pressure controls and a facemask mounted low pressure whistle alarm is described. The first stage of the system includes pair of pressure regulators connected in parallel with different outlet pressures, both of which reduce the pressure of the stored supply gas to pressures compatible with the second stage breathing demand regulator. A primary regulator in the first stage delivers a low output pressure to the demand regulator. In the event of a failure closed condition of the primary regulator an automatic transfer valve switches on the backup regulator. A warning that the supply pressure has been depleted is also provided by a supply pressure actuated transfer valve which transfers the output of the first stage pressure regulators from the primary to the backup regulator. The alarm is activated in either the failure closed condition or if the supply pressure is reduced to a dangerously low level.

  5. Running and Breathing in Mammals

    NASA Astrophysics Data System (ADS)

    Bramble, Dennis M.; Carrier, David R.

    1983-01-01

    Mechanical constraints appear to require that locomotion and breathing be synchronized in running mammals. Phase locking of limb and respiratory frequency has now been recorded during treadmill running in jackrabbits and during locomotion on solid ground in dogs, horses, and humans. Quadrupedal species normally synchronize the locomotor and respiratory cycles at a constant ratio of 1:1 (strides per breath) in both the trot and gallop. Human runners differ from quadrupeds in that while running they employ several phase-locked patterns (4:1, 3:1, 2:1, 1:1, 5:2, and 3:2), although a 2:1 coupling ratio appears to be favored. Even though the evolution of bipedal gait has reduced the mechanical constraints on respiration in man, thereby permitting greater flexibility in breathing pattern, it has seemingly not eliminated the need for the synchronization of respiration and body motion during sustained running. Flying birds have independently achieved phase-locked locomotor and respiratory cycles. This hints that strict locomotor-respiratory coupling may be a vital factor in the sustained aerobic exercise of endothermic vertebrates, especially those in which the stresses of locomotion tend to deform the thoracic complex.

  6. Study on the sampling of methadone from exhaled breath.

    PubMed

    Beck, Olof; Sandqvist, Sören; Böttcher, Michael; Eriksen, Paul; Franck, Johan; Palmskog, Göran

    2011-06-01

    This study aimed at develop and validate the procedure for collecting exhaled breath for drug testing. Patients receiving methadone maintenance treatment were recruited for the study. Methadone levels were measured using liquid chromatography- electrospray-tandem mass spectrometry. The sampling device was based on a 47-mm C(18) filter and used under pressure to aid flow through the filter. The mouth was rinsed before sampling, and the device was constructed to protect against any saliva contamination. Methadone was present in breath samples before and after the daily intake of methadone. The mean (± SD) pre-dose level was found to be 135 ± 109 pg/min (n = 48, median 121). The exhaled methadone increased after dose intake. Saliva levels of methadone were high in comparison with exhaled breath levels. Saliva contamination was suspected in about 10% of the collected samples. Similar results were obtained using 1, 3, and 10 min sampling times. The inter- and intraindividual variability were found to be similar and in the order of 50%. Alternative sampling using XAD-2 beads and solid-phase microextraction fiber was found to be possible and enables sampling with low back pressure and with no need for pump assistance. The presented results confirm that breath testing is a new possibility for the detection of drugs of abuse.

  7. The effect of breath holding, hyperventilation, and exercise on nasal resistance.

    PubMed

    Hasegawa, M; Kern, E B

    1978-12-01

    A group of 51 patients was studied by a technique of active posterior rhinomanometry that assessed the influence of breath holding, hyperventilation, and exercise on nasal resistance. Breath hodling of 30 seconds or longer produced a decrease in nasal resistance in most of the subjects tested. Hyperventilation had variable effects on nasal resistance, and exercise consistently decreased nasal resistance. These observations are consistent with the proposed effect of chemoreceptor stimulation on nasal airway resistance.

  8. Differences between roadside and subsequent evidential breath alcohol results and their forensic significance.

    PubMed

    Gullberg, R G

    1991-07-01

    Breath alcohol measurements for forensic purposes are typically not made at the time of a driving incident but at some later time. Therefore, the magnitude of variation in breath alcohol concentration (BrAC) following the time of arrest is of concern. The use of roadside preliminary breath test (PBT) instruments can provide data on BrAC closer to the time of a driving incident and allow for comparison with later evidential analysis. This retrospective study evaluates two distributions (N = 968): differences between PBT results and the first evidential breath test (PBT-BrAC1) and differences between two (duplicate) evidential breath alcohol tests (BrAC1-BrAC2). The two distributions were shown to vary from each other and from the normal with statistical significance (p less than .05). The PBT-BrAC1 distribution had greater variability (SD = .025) than the BrAC1-BrAC2 distribution (SD = .010). An important result was that the PBT was equal to (within duplicate sampling variability) or greater than BrAC1 in approximately 85.5% of the cases. The remaining 14.5% could not be explained by sampling variability within the duplicate test distribution. The variability in both distributions typically exceeds the normally accepted alcohol elimination rates. The conclusion is that differences between roadside and subsequent evidential breath results cannot be attributed solely to absorption or elimination kinetics. Intra-individual breath sample differences can be large and thus obscure the accurate evaluation of absorption and elimination rates. Breath tests conducted within approximately 2 hours of driving will reflect, within experimental uncertainty, the BrAC at the time of driving.

  9. Segmentation and classification of capnograms: application in respiratory variability analysis.

    PubMed

    Herry, C L; Townsend, D; Green, G C; Bravi, A; Seely, A J E

    2014-12-01

    Variability analysis of respiratory waveforms has been shown to provide key insights into respiratory physiology and has been used successfully to predict clinical outcomes. The current standard for quality assessment of the capnogram signal relies on a visual analysis performed by an expert in order to identify waveform artifacts. Automated processing of capnograms is desirable in order to extract clinically useful features over extended periods of time in a patient monitoring environment. However, the proper interpretation of capnogram derived features depends upon the quality of the underlying waveform. In addition, the comparison of capnogram datasets across studies requires a more practical approach than a visual analysis and selection of high-quality breath data. This paper describes a system that automatically extracts breath-by-breath features from capnograms and estimates the quality of individual breaths derived from them. Segmented capnogram breaths were presented to expert annotators, who labeled the individual physiological breaths into normal and multiple abnormal breath types. All abnormal breath types were aggregated into the abnormal class for the purpose of this manuscript, with respiratory variability analysis as the end-application. A database of 11,526 breaths from over 300 patients was created, comprising around 35% abnormal breaths. Several simple classifiers were trained through a stratified repeated ten-fold cross-validation and tested on an unseen portion of the labeled breath database, using a subset of 15 features derived from each breath curve. Decision Tree, K-Nearest Neighbors (KNN) and Naive Bayes classifiers were close in terms of performance (AUC of 90%, 89% and 88% respectively), while using 7, 4 and 5 breath features, respectively. When compared to airflow derived timings, the 95% confidence interval on the mean difference in interbreath intervals was ± 0.18 s. This breath classification system provides a fast and robust pre

  10. Cardiovascular Disease

    PubMed Central

    Grace, Sherry L; Fry, Rick; Cheung, Angela; Stewart, Donna E

    2004-01-01

    Health Issue Cardiovascular disease (CVD) is the leading cause of death in Canadian women and men. In general, women present with a wider range of symptoms, are more likely to delay seeking medial care and are less likely to be investigated and treated with evidence-based medications, angioplasty or coronary artery bypass graft than men. Key Findings In 1998, 78,964 Canadians died from CVD, almost half (39,197) were women. Acute myocardial infarction, which increases significantly after menopause, was the leading cause of death among women. Cardiovascular disease accounted for 21% of all hospital admissions for Canadian women over age 50 in 1999. Admissions to hospital for ischemic heart disease were more frequent for men, but the mean length of hospital stay was longer for women. Mean blood pressure increases with age in both men and women. After age 65, however, high blood pressure is more common among Canadian women. More than one-third of postmenopausal Canadian women have hypertension. Diabetes increases the mortality and morbidity associated with CVD in women more than it does in men. Depression also contributes to the incidence and recovery from CVD, particularly for women who experience twice the rate of depression as men. Data Gaps and Recommendations CVD needs to be recognized as a woman's health issue given Canadian mortality projections (particularly heart failure). Health professionals should be trained to screen, track, and address CVD risk factors among women, including hypertension, elevated lipid levels, smoking, physical inactivity, depression, diabetes and low socio-economic status. PMID:15345078

  11. Cardiovascular effects of basal insulins.

    PubMed

    Mannucci, Edoardo; Giannini, Stefano; Dicembrini, Ilaria

    2015-01-01

    Basal insulin is an important component of treatment for both type 1 and type 2 diabetes. One of the principal aims of treatment in patients with diabetes is the prevention of diabetic complications, including cardiovascular disease. There is some evidence, although controversial, that attainment of good glycemic control reduces long-term cardiovascular risk in both type 1 and type 2 diabetes. The aim of this review is to provide an overview of the potential cardiovascular safety of the different available preparations of basal insulin. Current basal insulin (neutral protamine Hagedorn [NPH], or isophane) and basal insulin analogs (glargine, detemir, and the more recent degludec) differ essentially by various measures of pharmacokinetic and pharmacodynamic effects in the bloodstream, presence and persistence of peak action, and within-subject variability in the glucose-lowering response. The currently available data show that basal insulin analogs have a lower risk of hypoglycemia than NPH human insulin, in both type 1 and type 2 diabetes, then excluding additional harmful effects on the cardiovascular system mediated by activation of the adrenergic system. Given that no biological rationale for a possible difference in cardiovascular effect of basal insulins has been proposed so far, available meta-analyses of publicly disclosed randomized controlled trials do not show any signal of increased risk of major cardiovascular events between the different basal insulin analogs. However, the number of available cardiovascular events in these trials is very small, preventing any clear-cut conclusion. The results of an ongoing clinical trial comparing glargine and degludec with regard to cardiovascular safety will provide definitive evidence. PMID:26203281

  12. Cardiovascular effects of basal insulins

    PubMed Central

    Mannucci, Edoardo; Giannini, Stefano; Dicembrini, Ilaria

    2015-01-01

    Basal insulin is an important component of treatment for both type 1 and type 2 diabetes. One of the principal aims of treatment in patients with diabetes is the prevention of diabetic complications, including cardiovascular disease. There is some evidence, although controversial, that attainment of good glycemic control reduces long-term cardiovascular risk in both type 1 and type 2 diabetes. The aim of this review is to provide an overview of the potential cardiovascular safety of the different available preparations of basal insulin. Current basal insulin (neutral protamine Hagedorn [NPH], or isophane) and basal insulin analogs (glargine, detemir, and the more recent degludec) differ essentially by various measures of pharmacokinetic and pharmacodynamic effects in the bloodstream, presence and persistence of peak action, and within-subject variability in the glucose-lowering response. The currently available data show that basal insulin analogs have a lower risk of hypoglycemia than NPH human insulin, in both type 1 and type 2 diabetes, then excluding additional harmful effects on the cardiovascular system mediated by activation of the adrenergic system. Given that no biological rationale for a possible difference in cardiovascular effect of basal insulins has been proposed so far, available meta-analyses of publicly disclosed randomized controlled trials do not show any signal of increased risk of major cardiovascular events between the different basal insulin analogs. However, the number of available cardiovascular events in these trials is very small, preventing any clear-cut conclusion. The results of an ongoing clinical trial comparing glargine and degludec with regard to cardiovascular safety will provide definitive evidence. PMID:26203281

  13. Breath isoprene concentrations in persons undergoing general anesthesia and in healthy volunteers.

    PubMed

    Hornuss, Cyrill; Zagler, Armin; Dolch, Michael E; Wiepcke, Dirk; Praun, Siegfried; Boulesteix, Anne-Laure; Weis, Florian; Apfel, Christian C; Schelling, Gustav

    2012-12-01

    Human breath contains an abundance of volatile organic compounds (VOCs). Analysis of breath VOC may be used for diagnosis of various diseases or for on-line monitoring in anesthesia and intensive care. However, VOC concentrations largely depend on the breath sampling method and have a large inter-individual variability. For the development of breath tests, the influence of breath sampling methods and study subject characteristics on VOC concentrations has to be known. Therefore, we investigated the VOC isoprene in 62 study subjects during anesthesia and 16 spontaneously breathing healthy volunteers to determine (a) the influence of artificial and spontaneous ventilation and (b) the influence of study subject characteristics on breath isoprene concentrations. We used ion molecule reaction mass spectrometry for high-resolution breath-by-breath analysis of isoprene. We found that persons during anesthesia had significantly increased inspiratory and end-expiratory isoprene breath concentrations. Measured isoprene concentrations (median [first quartile-third quartile]) were in the anesthesia group: 54 [40-79] ppb (inspiratory) and 224 [171-309] ppb (end-expiratory), volunteer group: 14 [11-17] ppb (inspiratory) and 174 [124-202] ppb (end-expiratory). Higher end-tidal CO(2) concentrations in ventilated subjects were associated with higher expiratory isoprene levels. Furthermore, inspiratory and end-expiratory isoprene concentrations were correlated during anesthesia (r = 0.603, p < 0.001). Multivariate analysis showed that men had significantly higher end-expiratory isoprene concentrations than women. Rebreathing of isoprene from the anesthesia machine possibly accounts for the observed increase in isoprene in the anesthesia group.

  14. Pharmacogenetics of cardiovascular drug therapy

    PubMed Central

    Peters, Bas J.M.; Klungel, Olaf H.; de Boer, Anthonius; Ch. Stricker, Bruno H.; Maitland-van der Zee, Anke-Hilse

    2009-01-01

    In developed countries cardiovascular disease is one of the leading causes of death. Cardiovascular drugs such as platelet aggregation inhibitors, oral anticoagulants, antihypertensives and cholesterol lowering drugs are abundantly prescribed to reduce risk of cardiovascular disease. Notable interindividual variation exists in the response to these pharmacotherapeutic interventions, which can be partially explained by factors such as gender, age, diet, concomitant drug use and environmental factors. Notwithstanding, a great part of this variability remains unknown. To a smaller or larger extent, genetic variability may contribute to the variability in response to these cardiovascular drugs. This review gives an overview of pharmacogenetic studies of genes that were reported to be associated with four commonly prescribed drugs/drug classes (platelet aggregation inhibitors, coumarins, antihypertensives and statins) and were studied at least 2 times with a similar outcome measure. In the field of cardiovascular drug therapy, polymorphisms in candidate genes such as the cycloxygenase-1, vitamin K reductase complex subunit 1, CYP2C9, alpha adducin and 3-hydroxy-3-methylglutaryl-CoA reductase have received a great amount of interest in the pharmacogenetics of aspirin, coumarins, antihypertensives and statins respectively. However, only variations in VKORC1 and CYP2C9 have consistently been associated with drug response (coumarins) and have clinical implications. Clinical trials should provide evidence for the effectiveness of genotyping before this procedure will be a part of every day anticoagulant therapy. In spite of the tremendous amount of publications in this field, there is no reason to advocate for genetic testing for any other drugs cardiovascular drug therapy yet. Current approaches in pharmacogenetic research do not seem to lead to results that meet our expectations of individualized medicine. Therefore, new approaches are needed addressing issues and

  15. Cardiovascular physiology and sleep.

    PubMed

    Murali, Narayana S; Svatikova, Anna; Somers, Virend K

    2003-05-01

    effects of sleep could be objectively differentiated from the effects of rest and recumbency. Furthermore, the specific effects of sleep onset and termination, and the effects of different sleep stages, could be assessed. Technological advances, with consequently enhanced and relatively non-invasive approaches to cardiovascular regulation, have greatly broadened our understanding of the effects of sleep stage on cardiovascular function. Continuous monitoring of simultaneous measures of polysomnographic and cardiovascular variables enables characterization of the effects of dynamic changes and rapid transitions in sleep stage, such as arousals. The capacity for measuring acute and immediate changes in autonomic, EEG and hemodynamic responses to sleep and arousal on a continuous basis has played an important role in enabling us to understand the interplay between changes in EEG and changes in the more peripheral measurements of neural and circulatory variables, such as sympathetic nerve traffic, heart rate (HR) and blood pressure (BP). Measurements of heart rate variability (HRV) (8-10), baroreflex sensitivity (BRS) (11-16), and intraneural measurement of sympathetic nerve traffic to muscle (MSNA) (17-22) and skin (SSNA) (23-24) have further advanced our understanding of mechanisms linking sleep and cardiovascular physiology.

  16. Application of end-expired breath sampling to estimate carboxyhemoglobin levels in community air pollution exposure assessments

    NASA Astrophysics Data System (ADS)

    Lambert, William E.; Colome, Steven D.; Wojciechowski, Sandra L.

    Measurement of carbon monoxide (CO) in end-expired air after breath-holding permits the estimation of blood carboxyhemoglobin (COHb) levels. Some literature suggests that the precision of the method decreases at low COHb levels. As part of a community exposure and health study, the end-expired breath method was applied to estimate COHb levels in 28 men with ischemic heart disease. Paired samples of blood and breath were collected at the beginning and end of the 24-h CO monitoring periods. The aggregate regression of all subjects' COHb on breath CO displayed high variability. However, the variability was substantially reduced for any particular subject, promoting the use of individualized blood-breath standard curves to improve the precision of COHb estimates made from breath CO. The ultimate accuracy of the blood-breath relationship could not be resolved by our data. Two major sources of error are identified. The observed person-to-person variability may be caused by physiologic factors or differences in ability to deliver an end-expired breath sample representative of alveolar air. This variation may also be due to instrumentation factors, specifically the accuracy of the IL282 CO-Oximeter at 0-3% levels. Further research into the sources of variability in the end-expired breath method is recommended. Epidemiologists using similar end-expired breath measurements to predict COHb levels should be cognizant of the magnitude and probable direction of the error in COHb estimates. This non-invasive method should continue to allow evaluation of the success of personal monitoring efforts and pharmacokinetic modeling of CO uptake in community exposure research.

  17. Breath alcohol test precision: an in vivo vs. in vitro evaluation.

    PubMed

    Gullberg, R G

    1989-12-01

    Random error is associated with breath alcohol measurements, as with all analytical methods. The total random uncertainty of a group of n measurements is typically determined by computing the standard deviation and requiring it to be less than some appropriate level (i.e., +/- 0.0042 g/210 l). The total random uncertainty has two primary sources; the instrumental method and the sample source. These are typically inseparable values. In breath alcohol testing the two primary sample sources are simulators and human breath. The present study evaluates ten groups of simulator samples consisting of ten measurements each on BAC Verifier Datamaster instruments. The data also includes ten breath alcohol measurements from each of 21 individuals following alcohol consumption. The range of standard deviations for the simulator samples was 0.0003-0.0022 g/210 l. The range of standard deviations for the human breath samples was 0.0015-0.0089 g/210 l. Two statistics that test for homogeneity for variances were applied. The simulator samples resulted in a Cochran's C test of 0.5000 and an Fmax test of 48.9. The human breath samples resulted in a Cochran's C test of 0.1519 and an Fmax test of 27.3. All were significant at P less than 0.001. The statistical tests demonstrated that the intragroup variability among the human subjects was comparable to the intragroup variability among the simulator samples. The data also demonstrates that the sample source (simulator or human) is probably the largest contributor to total random uncertainty. Therefore, when duplicate breath alcohol testing from individuals shows variability in the second decimal place the cause is differences in breath samples provided and not instrumental imprecision.

  18. Ultrasound lung "comets" increase after breath-hold diving.

    PubMed

    Lambrechts, Kate; Germonpré, Peter; Charbel, Brian; Cialoni, Danilo; Musimu, Patrick; Sponsiello, Nicola; Marroni, Alessandro; Pastouret, Frédéric; Balestra, Costantino

    2011-04-01

    The purpose of the study was to analyze the ultrasound lung comets (ULCs) variation, which are a sign of extra-vascular lung water. Forty-two healthy individuals performed breath-hold diving in different conditions: dynamic surface apnea; deep variable-weight apnea and shallow, face immersed without effort (static maximal and non-maximal). The number of ULCs was evaluated by means of an ultrasound scan of the chest, before and after breath-hold diving sessions. The ULC score increased significantly from baseline after dynamic surface apnea (p = 0.0068), after deep breath-hold sessions (p = 0.0018), and after static maximal apnea (p = 0.031). There was no statistically significant difference between the average increase of ULC scores after dynamic surface apnea and deep breath-hold diving. We, therefore, postulate that extravascular lung water accumulation may be due to other factors than (deep) immersion alone, because it occurs during dynamic surface apnea as well. Three mechanisms may be responsible for this. First, the immersion-induced hydrostatic pressure gradient applied on the body causes a shift of peripheral venous blood towards the thorax. Second, the blood pooling effect found during the diving response Redistributes blood to the pulmonary vascular bed. Third, it is possible that the intense involuntary diaphragmatic contractions occurring during the "struggle phase" of the breath-hold can also produce a blood shift from the pulmonary capillaries to the pulmonary alveoli. A combination of these factors may explain the observed increase in ULC scores in deep, shallow maximal and shallow dynamic apneas, whereas shallow non-maximal apneas seem to be not "ULC provoking".

  19. Breath Tests to Assess Alcoholic Liver Disease.

    PubMed

    Furnari, Manuele; Ahmed, Iftikhar; Erpecum, Karel J van; Savarino, Vincenzo; Giannini, Edoardo G

    2016-01-01

    The prevalence of Alcohol related Liver Disease (ALD) continues to rise all over the world due to changing drinking behaviour of the population. Liver disease due to excessive alcohol consumption causes significant morbidity and mortality, and poses a substantial economic burden to the health care resources. Early diagnosis and treatment of ALD may help prevent progression to cirrhosis and hepatocellular carcinoma. The last decade has seen a rising interest in potential use of non-invasive tests in clinical practice, including diagnosis and monitoring of chronic liver diseases. Over the past few decades, breath testing has been investigated extensively in the diagnosis of ALD, and has shown promising results in predicting the early stages of ALD. A variety of breath tests have been utilised in this regard including the13Clabelled breath tests, aminopyrine breath test , galactose breath test , methacetin breath test, and keto-isocaproic acid breath test. These tests have demonstrated good results in identification of both significant and severe liver disease among patients with ALD. Volatile Organic Compounds (VOC) are chemicals, which can be quantified in breath and other biological fluids, and represent physio-pathological activities within an individual. Alteration in the pattern of breath VOCs can be correlated with a number of diseases including ALD. Early stages of ALD can be detected using these breath tests, which can lead to adoption of preventive measures to reduce the progression of liver disease. This review focuses on the clinical utility of current and future breath tests, including breath VOC, as a non-invasive means of predicting early stages of ALD. PMID:27515960

  20. Free-breathing radial volumetric interpolated breath-hold examination vs breath-hold cartesian volumetric interpolated breath-hold examination magnetic resonance imaging of the liver at 1.5T

    PubMed Central

    Yedururi, Sireesha; Kang, HyunSeon C; Wei, Wei; Wagner-Bartak, Nicolaus A; Marcal, Leonardo P; Stafford, R Jason; Willis, Brandy J; Szklaruk, Janio

    2016-01-01

    AIM To compare breath-hold cartesian volumetric interpolated breath-hold examination (cVIBE) and free-breathing radial VIBE (rVIBE) and determine whether rVIBE could replace cVIBE in routine liver magnetic resonance imaging (MRI). METHODS In this prospective study, 15 consecutive patients scheduled for routine MRI of the abdomen underwent pre- and post-contrast breath-hold cVIBE imaging (19 s acquisition time) and free-breathing rVIBE imaging (111 s acquisition time) on a 1.5T Siemens scanner. Three radiologists with 2, 4, and 8 years post-fellowship experience in abdominal imaging evaluated all images. The radiologists were blinded to the sequence types, which were presented in a random order for each patient. For each sequence, the radiologists scored the cVIBE and rVIBE images for liver edge sharpness, hepatic vessel clarity, presence of artifacts, lesion conspicuity, fat saturation, and overall image quality using a five-point scale. RESULTS Compared to rVIBE, cVIBE yielded significantly (P < 0.001) higher scores for liver edge sharpness (mean score, 3.87 vs 3.37), hepatic-vessel clarity (3.71 vs 3.18), artifacts (3.74 vs 3.06), lesion conspicuity (3.81 vs 3.2), and overall image quality (3.91 vs 3.24). cVIBE and rVIBE did not significantly differ in quality of fat saturation (4.12 vs 4.03, P = 0.17). The inter-observer variability with respect to differences between rVIBE and cVIBE scores was close to zero compared to random error and inter-patient variation. Quality of rVIBE images was rated as acceptable for all parameters. CONCLUSION rVIBE cannot replace cVIBE in routine liver MRI. At 1.5T, free-breathing rVIBE yields acceptable, although slightly inferior image quality compared to breath-hold cVIBE. PMID:27551341

  1. Impact of variables of the P-selectin - P-selectin glycoprotein ligand-1 axis on leukocyte-platelet interactions in cardiovascular disease.

    PubMed

    Gremmel, Thomas; Koppensteiner, Renate; Kaider, Alexandra; Eichelberger, Beate; Mannhalter, Christine; Panzer, Simon

    2015-04-01

    The formation of leukocyte-platelet aggregates (LPA), through the P-selectin - P-selectin glycoprotein ligand (PSGL)-1 axis, plays a pivotal role in atherothrombosis. In order to investigate the influence of platelet (pP-selectin) and soluble P-selectin (sP-selectin), and of variations in the genes encoding for P-selectin (SELP) and PSGL-1 (SELPLG) on LPA formation, we assessed monocyte (MPA)- and neutrophil-platelet aggregates (NPA) as well as pP-selectin by flow cytometry in 263 patients undergoing angioplasty and stenting. sP-selectin was determined by ELISA, the SELP Pro715 allele and the SELPLG Ile62 allele were determined by allele specific PCR. The Pro715 allele was significantly associated with lower levels of in vivo pP-selectin and sP-selectin, while agonists´ inducible pP-selectin was not influenced by the Pro715 allele. PP-selectin was significantly associated with MPA and NPA formation. The in vivo formation of MPA and NPA depended to 19 % and 7.4 %, respectively, on in vivo pP-selectin, irrespective of the Pro715 allele and the Ile62 allele carrier status. TRAP-6 inducible MPA and NPA depended to 34 % and 27 %, respectively, on TRAP-6 inducible pP-selectin, but were independent of the Pro715 allele carrier status. Carriers of the Ile62 allele showed a stronger correlation between TRAP-6 inducible pP-selectin and TRAP-6 inducible MPA/NPA than non-carriers. Furthermore, TRAP-6 inducible NPA were higher in Ile62 allele carriers, which suggests higher thrombin sensitivity. In conclusion, our findings point to the significant role of pP-selectin for MPA and NPA formation, while other variables like sP-selectin, the SELP Pro715 allele and the SELPLG Ile62 allele have less influence.

  2. Qigong--Chinese breathing exercise.

    PubMed

    Koh, T C

    1982-01-01

    Qigong is an ancient Chinese breathing exercise with meditation which is being developed today for therapy of chronic illnesses in the People's Republic of China. It is claimed to cure gastric ulcers, hypertension, anxiety neurosis, otitis media, cancer and has even been used as a form of anaesthesia. Although the physiological effects produced by Qigong resemble those of meditation, there are certain features that are unique and often mysterious. Research in the future may prove Qigong to be a useful adjunct in the practice of medicine.

  3. Mitochondrial cytopathies and cardiovascular disease.

    PubMed

    Dominic, Elizabeth A; Ramezani, Ali; Anker, Stefan D; Verma, Mukesh; Mehta, Nehal; Rao, Madhumathi

    2014-04-01

    The global epidemic of cardiovascular disease remains the leading cause of death in the USA and across the world. Functional and structural integrity of mitochondria are essential for the physiological function of the cardiovascular system. The metabolic adaptation observed in normal heart is lost in the failing myocardium, which becomes progressively energy depleted leading to impaired myocardial contraction and relaxation. Uncoupling of electron transfer from ATP synthesis leads to excess generation of reactive species, leading to widespread cellular injury and cardiovascular disease. Accumulation of mitochondrial DNA mutation has been linked to ischaemic heart disease, cardiomyopathy and atherosclerotic vascular disease. Mitochondria are known to regulate apoptotic and autophagic pathways that have been shown to play an important role in the development of cardiomyopathy and atherosclerosis. A number of pharmacological and non-pharmacological treatment options have been explored in the management of mitochondrial diseases with variable success. PMID:24449718

  4. Breathing

    MedlinePlus Videos and Cool Tools

    ... size of the thoracic cavity and decreases the pressure inside. As a result, air rushes in and ... volume of the thoracic cavity decreases, while the pressure within it increases. As a result, the lungs ...

  5. The effect of a single session of short duration biofeedback-induced deep breathing on measures of heart rate variability during laboratory-induced cognitive stress: a pilot study.

    PubMed

    Prinsloo, Gabriell E; Derman, Wayne E; Lambert, Michael I; Laurie Rauch, H G

    2013-06-01

    This study examines the acute effect of heart rate variability (HRV) biofeedback on HRV measures during and immediately after biofeedback and during the following laboratory-induced stress. Eighteen healthy males exposed to work-related stress were randomised into an HRV biofeedback group (BIO) or a comparative group (COM). Subjects completed a modified Stroop task before (Stroop 1) and after (Stroop 2) the intervention. Both groups had similar physiological responses to stress in Stroop 1. In Stroop 2, the COM group responded similarly to the way they did to Stroop 1: respiratory frequency (RF) and heart rate (HR) increased, RMSSD and high frequency (HF) power decreased or had a tendency to decrease, while low frequency (LF) power showed no change. The BIO group responded differently in Stroop 2: while RF increased and LF power decreased, HR, RMSSD and HF power showed no change. In the BIO group, RMSSD was higher in Stroop 2 compared to Stroop 1. In conclusion, HRV biofeedback induced a short term carry-over effect during both the following rest period and laboratory-induced stress suggesting maintained HF vagal modulation in the BIO group after the intervention, and maintained LF vagal modulation in the COM group. PMID:23435801

  6. News from the Breath Analysis Summit 2011.

    PubMed

    Corradi, Massimo; Mutti, Antonio

    2012-05-23

    This special section highlights some of the important work presented at the Breath Analysis Summit 2011, which was held in Parma (Italy) from 11 to 14 September 2011. The meeting, which was jointly organized by the International Association for Breath Research and the University of Parma, was attended by more than 250 delegates from 33 countries, and offered 34 invited lectures and 64 unsolicited scientific contributions. The summit was organized to provide a forum to scientists, engineers and clinicians to present their latest findings and to meet industry executives and entrepreneurs to discuss key trends, future directions and technologies available for breath analysis. A major focus was on nitric oxide, exhaled breath condensate, electronic nose, mass spectrometry and newer sensor technologies. Medical applications ranged from asthma and other respiratory diseases to gastrointestinal disease, occupational diseases, critical care and cancer. Most people identify breath tests with breathalysers used by police to estimate ethanol concentration in blood. However, breath testing has far more sophisticated applications. Breath analysis is rapidly evolving as a new frontier in medical testing for disease states in the lung and beyond. Every individual has a breath fingerprint-or 'breathprint'-that can provide useful information about his or her state of health. This breathprint comprises the many thousands of molecules that are expelled with each breath we exhale. Breath research in the past few years has uncovered the scientific and molecular basis for such clinical observations. Relying on mass spectrometry, we have been able to identify many such unique substances in exhaled breath, including gases, such as nitric oxide (NO) and carbon monoxide (CO), and a wide array of volatile organic compounds. Exhaled breath also carries aerosolized droplets that can be collected as an exhaled breath condensate that contains endogenously produced non-volatile compounds. Breath

  7. Whole left ventricular functional assessment from two minutes free breathing multi-slice CINE acquisition

    NASA Astrophysics Data System (ADS)

    Usman, M.; Atkinson, D.; Heathfield, E.; Greil, G.; Schaeffter, T.; Prieto, C.

    2015-04-01

    Two major challenges in cardiovascular MRI are long scan times due to slow MR acquisition and motion artefacts due to respiratory motion. Recently, a Motion Corrected-Compressed Sensing (MC-CS) technique has been proposed for free breathing 2D dynamic cardiac MRI that addresses these challenges by simultaneously accelerating MR acquisition and correcting for any arbitrary motion in a compressed sensing reconstruction. In this work, the MC-CS framework is combined with parallel imaging for further acceleration, and is termed Motion Corrected Sparse SENSE (MC-SS). Validation of the MC-SS framework is demonstrated in eight volunteers and three patients for left ventricular functional assessment and results are compared with the breath-hold acquisitions as reference. A non-significant difference (P > 0.05) was observed in the volumetric functional measurements (end diastolic volume, end systolic volume, ejection fraction) and myocardial border sharpness values obtained with the proposed and gold standard methods. The proposed method achieves whole heart multi-slice coverage in 2 min under free breathing acquisition eliminating the time needed between breath-holds for instructions and recovery. This results in two-fold speed up of the total acquisition time in comparison to the breath-hold acquisition.

  8. Slow breathing training reduces resting blood pressure and the pressure responses to exercise.

    PubMed

    Jones, C U; Sangthong, B; Pachirat, O; Jones, D A

    2015-01-01

    Slow breathing training reduces resting blood pressure, probably by modifying central autonomic control, but evidence for this is lacking. The pressor response to static handgrip exercise is a measure of autonomic control and the aim of this study was to determine whether slow breathing training modulates the pressor responses to exercise of untrained muscles. Twenty hypertensive patients trained for 8 weeks, 10 with unloaded slow breathing (Unloaded) and 10 breathing against an inspiratory load of 20 cm H(2)O (Loaded). Ten subjects were untrained controls. Subjects performed a 2 min handgrip pressor test (30 % MVC) pre- and post-training, and blood pressure and heart rate (HR) were measured before the contraction, at the end and following 2 min recovery. Resting systolic (sBP) and HR were reduced as a result of training, as reported previously. After training there was both a smaller pressor response to hand grip exercise and a more rapid recovery of sBP and HR compared to pre-training. There were no changes in the Controls and no differences between the Unloaded and Loaded groups. Combining the two training groups, the sBP response to handgrip exercise after training was reduced by 10 mm Hg (95 % CI: -7, -13) and HR by 5 bpm (95 % CI: -4, -6), all p<0.05. These results are consistent with slow breathing training modifying central mechanisms regulating cardiovascular function. PMID:25804100

  9. Methodology and technology for peripheral and central blood pressure and blood pressure variability measurement: current status and future directions - Position statement of the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability.

    PubMed

    Stergiou, George S; Parati, Gianfranco; Vlachopoulos, Charalambos; Achimastos, Apostolos; Andreadis, Emanouel; Asmar, Roland; Avolio, Alberto; Benetos, Athanase; Bilo, Grzegorz; Boubouchairopoulou, Nadia; Boutouyrie, Pierre; Castiglioni, Paolo; de la Sierra, Alejandro; Dolan, Eamon; Head, Geoffrey; Imai, Yutaka; Kario, Kazuomi; Kollias, Anastasios; Kotsis, Vasilis; Manios, Efstathios; McManus, Richard; Mengden, Thomas; Mihailidou, Anastasia; Myers, Martin; Niiranen, Teemu; Ochoa, Juan Eugenio; Ohkubo, Takayoshi; Omboni, Stefano; Padfield, Paul; Palatini, Paolo; Papaioannou, Theodore; Protogerou, Athanasios; Redon, Josep; Verdecchia, Paolo; Wang, Jiguang; Zanchetti, Alberto; Mancia, Giuseppe; O'Brien, Eoin

    2016-09-01

    Office blood pressure measurement has been the basis for hypertension evaluation for almost a century. However, the evaluation of blood pressure out of the office using ambulatory or self-home monitoring is now strongly recommended for the accurate diagnosis in many, if not all, cases with suspected hypertension. Moreover, there is evidence that the variability of blood pressure might offer prognostic information that is independent of the average blood pressure level. Recently, advancement in technology has provided noninvasive evaluation of central (aortic) blood pressure, which might have attributes that are additive to the conventional brachial blood pressure measurement. This position statement, developed by international experts, deals with key research and practical issues in regard to peripheral blood pressure measurement (office, home, and ambulatory), blood pressure variability, and central blood pressure measurement. The objective is to present current achievements, identify gaps in knowledge and issues concerning clinical application, and present relevant research questions and directions to investigators and manufacturers for future research and development (primary goal).

  10. Methodology and technology for peripheral and central blood pressure and blood pressure variability measurement: current status and future directions - Position statement of the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability.

    PubMed

    Stergiou, George S; Parati, Gianfranco; Vlachopoulos, Charalambos; Achimastos, Apostolos; Andreadis, Emanouel; Asmar, Roland; Avolio, Alberto; Benetos, Athanase; Bilo, Grzegorz; Boubouchairopoulou, Nadia; Boutouyrie, Pierre; Castiglioni, Paolo; de la Sierra, Alejandro; Dolan, Eamon; Head, Geoffrey; Imai, Yutaka; Kario, Kazuomi; Kollias, Anastasios; Kotsis, Vasilis; Manios, Efstathios; McManus, Richard; Mengden, Thomas; Mihailidou, Anastasia; Myers, Martin; Niiranen, Teemu; Ochoa, Juan Eugenio; Ohkubo, Takayoshi; Omboni, Stefano; Padfield, Paul; Palatini, Paolo; Papaioannou, Theodore; Protogerou, Athanasios; Redon, Josep; Verdecchia, Paolo; Wang, Jiguang; Zanchetti, Alberto; Mancia, Giuseppe; O'Brien, Eoin

    2016-09-01

    Office blood pressure measurement has been the basis for hypertension evaluation for almost a century. However, the evaluation of blood pressure out of the office using ambulatory or self-home monitoring is now strongly recommended for the accurate diagnosis in many, if not all, cases with suspected hypertension. Moreover, there is evidence that the variability of blood pressure might offer prognostic information that is independent of the average blood pressure level. Recently, advancement in technology has provided noninvasive evaluation of central (aortic) blood pressure, which might have attributes that are additive to the conventional brachial blood pressure measurement. This position statement, developed by international experts, deals with key research and practical issues in regard to peripheral blood pressure measurement (office, home, and ambulatory), blood pressure variability, and central blood pressure measurement. The objective is to present current achievements, identify gaps in knowledge and issues concerning clinical application, and present relevant research questions and directions to investigators and manufacturers for future research and development (primary goal). PMID:27214089

  11. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American National Standards... 42 Public Health 1 2013-10-01 2013-10-01 false Compressed breathing gas and liquefied breathing... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed...

  12. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American National Standards... 42 Public Health 1 2012-10-01 2012-10-01 false Compressed breathing gas and liquefied breathing... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed...

  13. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American National Standards... 42 Public Health 1 2014-10-01 2014-10-01 false Compressed breathing gas and liquefied breathing... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed...

  14. Resonant breathing biofeedback training for stress reduction among manufacturing operators.

    PubMed

    Sutarto, Auditya Purwandini; Wahab, Muhammad Nubli Abdul; Zin, Nora Mat

    2012-01-01

    The aim of this study was to examine the effect of resonant breathing biofeedback training for reducing stress among manufacturing operators. Resonant breathing biofeedback works by teaching people to recognize their involuntary heart rate variability and to control patterns of this physiological response. Thirty-six female operators from an electronic manufacturing factory were randomly assigned as the experimental group (n = 19) and the control group (n = 17). The participants of the intervention received 5 weekly sessions of biofeedback training. Physiological stress profiles and self-perceived depression, anxiety, and stress scale (DASS) were assessed at pre- and post-intervention. Results indicated that depression, anxiety, and stress significantly decreased after the training in the experimental group; they were supported by a significant increase in physiological measures. Overall, these results support the potential application of resonant biofeedback training to reduce negative emotional symptoms among industrial workers. PMID:23294659

  15. The effects of breathing with mainly inspiration or expiration on pulmonary function and chest expansion

    PubMed Central

    Woo, Seong-Dae; Kim, Tae-Ho; Lim, Jin-Yong

    2016-01-01

    [Purpose] This study aimed to determine the effects of inspiration- and expiration-oriented breathing on pulmonary function and chest expansion. [Subjects and Methods] Twenty healthy male university students were divided randomly into inspiration-oriented and expiration-oriented breathing groups. Their pulmonary function and chest size during inspiration or expiration were evaluated and then re-evaluated after 15 minutes of breathing exercise five times a week for four weeks. [Results] The breathing with mainly inspiration group (BMIG) showed significant differences in chest size during inspiration (CSI), chest expansion values (CEVs), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow (PEF) after four weeks. The breathing with mainly expiration group (BMEG) showed significant differences in all measured variables except CSI. Comparison of the groups after exercise showed that the BMEG demonstrated differences from the BMIG in chest size during expiration (CSE), CEV, and PEF. Comparison of the changes in variables after exercise showed that the BMEG demonstrated significantly different changes in CSE, CEV, FEV1/FVC, and PEF. The BMIG showed a significantly different change in FVC. [Conclusion] Although both groups demonstrated improvements in pulmonary function and chest expansion, inter-group differences were observed. Therefore, inspiration- or expiration-oriented breathing may be recommended differently according to the desired outcome. PMID:27134386

  16. Protective supplied breathing air garment

    DOEpatents

    Childers, E.L.; Hortenau, E.F. von.

    1984-07-10

    A breathing air garment is disclosed for isolating a wearer from hostile environments containing toxins or irritants includes a suit and a separate head protective enclosure or hood engaging a suit collar in sealing attachment. The hood and suit collar are cylindrically shaped and dimensioned to enable the wearer to withdraw his hands from the suit sleeves to perform manual tasks within the hood interior. Breathing air is supplied from an external air line with an air delivery hose attached to the hood interior. The hose feeds air into an annular halo-like fiber-filled plenum having spaced discharge orifices attached to the hood top wall. A plurality of air exhaust/check valves located at the suit extremities cooperate with the hood air delivery system to provide a cooling flow of circulating air from the hood throughout the suit interior. A suit entry seal provided on the suit rear torso panel permits access into the suit and is sealed with an adhesive sealing flap. 17 figs.

  17. Protective supplied breathing air garment

    DOEpatents

    Childers, Edward L.; von Hortenau, Erik F.

    1984-07-10

    A breathing air garment for isolating a wearer from hostile environments containing toxins or irritants includes a suit and a separate head protective enclosure or hood engaging a suit collar in sealing attachment. The hood and suit collar are cylindrically shaped and dimensioned to enable the wearer to withdraw his hands from the suit sleeves to perform manual tasks within the hood interior. Breathing air is supplied from an external air line with an air delivery hose attached to the hood interior. The hose feeds air into an annular halo-like fiber-filled plenum having spaced discharge orifices attached to the hood top wall. A plurality of air exhaust/check valves located at the suit extremities cooperate with the hood air delivery system to provide a cooling flow of circulating air from the hood throughout the suit interior. A suit entry seal provided on the suit rear torso panel permits access into the suit and is sealed with an adhesive sealing flap.

  18. Submarines, spacecraft and exhaled breath.

    PubMed

    Pleil, Joachim D; Hansel, Armin

    2012-03-01

    Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another

  19. Submarines, spacecraft and exhaled breath.

    PubMed

    Pleil, Joachim D; Hansel, Armin

    2012-03-01

    Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another

  20. Correlates of Serum C-Reactive Protein (CRP) - No Association With Sleep Duration or Sleep Disordered Breathing

    PubMed Central

    Taheri, Shahrad; Austin, Diane; Lin, Ling; Nieto, F. Javier; Young, Terry; Mignot, Emmanuel

    2007-01-01

    Study Objectives: Increasing evidence suggests that alterations in sleep duration are associated with cardiovascular disease (CVD) and mortality. Additionally, sleep disordered breathing (SDB), which is associated with disturbed nighttime sleep and hypoxemia, may be an independent risk factor for CVD. The inflammatory marker, C-reactive protein (CRP), is an important predictor of CVD. We investigated potential associations between circulating CRP, sleep duration, and SDB. Design: Cross-sectional Study. Population: Participants were 907 adults from the Wisconsin Sleep Cohort Study (WSCS). Measurements and Results: CRP was measured after overnight polysomnography. The relationships between CRP and sleep parameters were evaluated using multiple linear regression with and without controlling for age, sex, and body mass index (BMI) and other potential confounders. CRP was found to be higher for women and had a strong positive correlation with age and BMI. CRP showed a significant positive association with current smoking, waist-hip ratio (WHR), LDL-cholesterol, triglycerides, leptin, and insulin, independent of age, sex, and BMI. Significant independent negative associations for CRP were observed with HDL-cholesterol (HDL), insulin sensitivity (quantitative insulin sensitivity check index [QUICKI]), and hours of exercise. There was a significant positive association between CRP levels and the apnea-hypopnea index (AHI, the measure of SDB), but these relationships were not significant after adjustment for age, sex, and BMI. No significant association between CRP levels and measures of sleep duration (polysomnographic and self-reported) were found. Conclusion: There was no significant association between CRP levels and sleep duration. The lack of an independent association between CRP levels and SDB suggests that the reported relationship between these 2 variables may be primarily driven by their association with obesity. Citation: Taheri S; Austin D; Lin L; Nieto FJ

  1. NASA firefighters breathing system program report

    NASA Technical Reports Server (NTRS)

    Wood, W. B.

    1977-01-01

    Because of the rising incidence of respiratory injury to firefighters, local governments expressed the need for improved breathing apparatus. A review of the NASA firefighters breathing system program, including concept definition, design, development, regulatory agency approval, in-house testing, and program conclusion is presented.

  2. How Does a Hopping Kangaroo Breathe?

    ERIC Educational Resources Information Center

    Giuliodori, Mauricio J.; Lujan, Heidi L.; Janbaih, Hussein; DiCarlo, Stephen E.

    2010-01-01

    We developed a model to demonstrate how a hopping kangaroo breathes. Interestingly, a kangaroo uses less energy to breathe while hopping than while standing still. This occurs, in part, because rather than using muscle power to move air into and out of the lungs, air is pulled into (inspiration) and pushed out of (expiration) the lungs as the…

  3. BREATHING PATTERN DISORDERS AND FUNCTIONAL MOVEMENT

    PubMed Central

    Dr. Esformes, Joseph

    2014-01-01

    Study Design: Experimental design Background: Normal breathing mechanics play a key role in posture and spinal stabilization. Breathing Pattern Disorders (BPD) have been shown to contribute to pain and motor control deficits, which can result in dysfunctional movement patterns. The Functional Movement Screen™ (FMS™) has been shown to accurately predict injury in individuals who demonstrate poor movement patterns. The role BPD play on functional movement is not well established. Furthermore, there is currently no single test to clinically diagnose BPD. A variety of methods are used, but correlations between them are poor. Purpose: To examine the relationship between BPD and functional movement and identify correlations between different measures of BPD. Methods: Breathing was assessed in 34 healthy individuals using a multi‐dimensional approach that included biomechanical, biochemical, breathing related symptoms, and breathing functionality measures. Movement was assessed using the FMS™. Analysis, involving independent t‐tests and Pearson correlation were performed to identify associations between measures. Results: Individuals who exhibited biochemical and biomechanical signs of BPD were significantly more likely to score poorly on the FMS™. These studied measures of BPD correlated highly with each other. Conclusion: These results demonstrate the importance of diaphragmatic breathing on functional movement. Inefficient breathing could result in muscular imbalance, motor control alterations, and physiological adaptations that are capable of modifying movement. These findings provide evidence for improved breathing evaluations by clinicians. Level of Evidence: 2B PMID:24567853

  4. EXHALED BREATH ANALYSIS FOR HUMAN EXPOSURE RESEARCH

    EPA Science Inventory

    Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that...

  5. Rapid eye movement sleep in breath holders.

    PubMed

    Kohyama, J; Hasegawa, T; Shimohira, M; Fukumizu, M; Iwakawa, Y

    2000-07-01

    One-night polysomnography was performed on seven subjects suffering from breath-holding spells, including one whose death was suggested to be a consequence of a breath-holding spell. The fatal case showed no rapid eye movements (REMs) during REM sleep, although he exhibited REMs during wakefulness. The average numbers of both REMs and bursts of REMs in REM sleep in the other six breath holders were significantly lower than those in age-matched controls. The breath holders showed no airway obstruction, desaturation, or sleep fragmentation. Since the rapid ocular activity in REM sleep is generated in the brain stem, we hypothesized that a functional brainstem disturbance is involved in the occurrence of breath-holding spells.

  6. Breathing evaluation and retraining in manual therapy.

    PubMed

    McLaughlin, Laurie

    2009-07-01

    Patients with back and neck pain commonly seek body work yet there are some who do not experience full recovery with the typical tool kit of manual therapy, education and exercise, suggesting the need for additional clinical approaches. Epidemiological literature linking back pain with breathing difficulties suggests one possibility. Altered motor control associated with back and neck pain appears to negatively impact breathing mechanics, which may have negative consequences on respiratory chemistry. Changes in respiratory chemistry can have profound effects on body system function. Altered breathing has been recognized for many years as a potential source of a wide variety of unexplained symptoms. There has been controversy around accurate diagnosis with symptoms and questionnaires often being the only methods used. Capnography, which is routinely used in critical care settings, offers an objective measure of respiratory chemistry providing physiological data on which to base a diagnosis of poor breathing. Capnography can also be used as biofeedback to guide breathing retraining.

  7. Computer simulation of breathing systems for divers

    SciTech Connect

    Sexton, P.G.; Nuckols, M.L.

    1983-02-01

    A powerful new tool for the analysis and design of underwater breathing gas systems is being developed. A versatile computer simulator is described which makes possible the modular ''construction'' of any conceivable breathing gas system from computer memory-resident components. The analysis of a typical breathing gas system is demonstrated using this simulation technique, and the effects of system modifications on performance of the breathing system are shown. This modeling technique will ultimately serve as the foundation for a proposed breathing system simulator under development by the Navy. The marriage of this computer modeling technique with an interactive graphics system will provide the designer with an efficient, cost-effective tool for the development of new and improved diving systems.

  8. Breath Testing for Small Intestinal Bacterial Overgrowth: Should We Bother?

    PubMed

    Pimentel, Mark

    2016-03-01

    The hydrogen breath test is based on following breath hydrogen levels after the administration of a carbohydrate (most commonly lactulose) to a patient with suspected small intestinal bacterial overgrowth. The test is based on the interaction between the administered carbohydrate and the intestinal bacteria. The resulting fermentation produces hydrogen. A positive breath test is based on a breath hydrogen rise prior to the expected arrival time in the highly microbial cecum. Despite renewed enthusiasm for breath testing in recent years due to associations with conditions such as irritable bowel syndrome, breath testing poses many challenges. In this argument against breath testing, several pitfalls that complicate breath testing will be described. PMID:26902227

  9. 46 CFR 197.450 - Breathing gas tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... commencement of diving operations, at the umbilical or underwater breathing apparatus connection point for the... underwater breathing apparatus connection point for the diver, for percentage of oxygen....

  10. Particle concentration in exhaled breath

    SciTech Connect

    Fairchild, C.I.; Stampfer, J.F.

    1987-11-01

    Measurements were made of the number of concentration of particles in exhaled breath under various conditions of exercise. A laser light scattering particle spectrometer was used to count particles exhaled by test subjects wearing respirators in a challenge environment of clean, dry air. Precautions were taken to ensure that particles were not generated by the respirators and that no extraneous water or other particles were produced in the humid exhaled air. The number of particles detected in exhales air varied over a range from <0.10 to approx. 4 particles/cm/sup 3/ depending upon the test subject and his activity. Subjects at rest exhaled the lowest concentration of particles, whereas exercises producing a faster respiration rate caused increased exhalation of particles. Exhaled particle concentration can limit the usefulness of nondiscriminating, ambient challenge aerosols for the fit testing of highly protective respirators.

  11. Cardiovascular and Postural Control Interactions during Hypergravity: Effects on Cerebral Autoregulation in Males and Females

    NASA Astrophysics Data System (ADS)

    Goswami, Nandu; Blaber, Andrew; Bareille, Marie-Pierre; Beck, Arnaud; Avan, Paul; Bruner, Michelle; Hinghofer-Szalkay, Helmut

    2012-07-01

    Orthostatic intolerance remains a problem upon return to Earth from the microgravity environment of spaceflight. A variety of conditions including hypovolemia, cerebral vasoconstriction, cerebral or peripheral vascular disease, or cardiac arrhythmias may result in syncope if the person remains upright. Current research indicates that there is a greater dependence on visual and somatosensory information at the beginning of space flight with a decreased otolith gain during prolonged space flight (Herault et al., 2002). The goal of the research is to further our understanding of the fundamental adaptive homeostatic mechanisms involved in gravity related changes in cardiovascular and postural function. Cardiovascular, cerebrovascular, and postural sensory motor control systems in male and female participants before, during, and after exposure to graded levels of hyper-G were investigated. Hypotheses: 1) Activation of skeletal muscle pump will be directly related to the degree of orthostatic stress. 2) Simultaneous measurement of heart rate, blood pressure and postural sway will predict cardio-postural stability. Blood pressure and heart rate (means and variability), postural sway, center of pressure (COP), baroreflex function, calf blood flow, middle cerebral artery blood flow, non-invasive intracranial pressure measurements, and two-breath CO2 were measured. Results from the study will be used to provide an integrated insight into mechanisms of cardio-postural control and cerebral autoregulation, which are important aspects of human health in flights to Moon, Mars and distant planets.

  12. Cardiovascular disease risks in adult Native and Mexican Americans with a history of alcohol use disorders: association with cardiovascular autonomic control.

    PubMed

    Criado, José R; Gilder, David A; Kalafut, Mary A; Ehlers, Cindy L

    2016-04-01

    Hypertension and obesity are serious health problems that have been associated with an increased risk of cardiovascular disease (CVD). We recently showed a relationship between hypertension, obesity and cardiovagal control in a sample of Native and Mexican Americans at high risk of alcohol use disorders (AUD). While studies have shown that Native and Mexican Americans exhibit high rates of AUD, the consequences of AUD on CVD risk factors and their relationship with cardiovascular autonomic control is not well understood in these ethnic groups. This study investigated whether an association could be demonstrated between cardiovascular autonomic control and several CVD risk factors in Native and Mexican American men and women (n = 228) who are literate in English and are residing legally in San Diego County. Participants with lifetime history of AUD showed higher rates of systolic and diastolic hypertension and obesity than participants without lifetime AUD. Lifetime AUD was significantly associated with reduced HR response to deep breathing (HRDB) measure of cardiovagal control, higher current drinking quantity, and obesity. Reduced HRDB was also associated with increased systolic pre-hypertension or hypertension (pre-/hypertension) and with higher diastolic blood pressure in a linear regression model that included several diagnostic and demographic variables. HRDB and time- and frequency-domain measures of cardiovagal control were significantly reduced in participants with diastolic pre-/hypertension. These data suggest that lower cardiovagal control may play a role in the prevalence of systolic and diastolic pre-/hypertension in a community sample with a history of alcohol and substance use disorders.

  13. Cardiovascular disease risks in adult Native and Mexican Americans with a history of alcohol use disorders: association with cardiovascular autonomic control.

    PubMed

    Criado, José R; Gilder, David A; Kalafut, Mary A; Ehlers, Cindy L

    2016-04-01

    Hypertension and obesity are serious health problems that have been associated with an increased risk of cardiovascular disease (CVD). We recently showed a relationship between hypertension, obesity and cardiovagal control in a sample of Native and Mexican Americans at high risk of alcohol use disorders (AUD). While studies have shown that Native and Mexican Americans exhibit high rates of AUD, the consequences of AUD on CVD risk factors and their relationship with cardiovascular autonomic control is not well understood in these ethnic groups. This study investigated whether an association could be demonstrated between cardiovascular autonomic control and several CVD risk factors in Native and Mexican American men and women (n = 228) who are literate in English and are residing legally in San Diego County. Participants with lifetime history of AUD showed higher rates of systolic and diastolic hypertension and obesity than participants without lifetime AUD. Lifetime AUD was significantly associated with reduced HR response to deep breathing (HRDB) measure of cardiovagal control, higher current drinking quantity, and obesity. Reduced HRDB was also associated with increased systolic pre-hypertension or hypertension (pre-/hypertension) and with higher diastolic blood pressure in a linear regression model that included several diagnostic and demographic variables. HRDB and time- and frequency-domain measures of cardiovagal control were significantly reduced in participants with diastolic pre-/hypertension. These data suggest that lower cardiovagal control may play a role in the prevalence of systolic and diastolic pre-/hypertension in a community sample with a history of alcohol and substance use disorders. PMID:26758567

  14. Amplitude gating for a coached breathing approach in respiratory gated 10 MV flattening filter-free VMAT delivery.

    PubMed

    Viel, Francis; Lee, Richard; Gete, Ermias; Duzenli, Cheryl

    2015-01-01

    The purpose of this study was to investigate amplitude gating combined with a coached breathing strategy for 10 MV flattening filter-free (FFF) volumetric-modulated arc therapy (VMAT) on the Varian TrueBeam linac. Ten patient plans for VMAT SABR liver were created using the Eclipse treatment planning system (TPS). The verification plans were then transferred to a CT-scanned Quasar phantom and delivered on a TrueBeam linac using a 10 MV FFF beam and Varian's real-time position management (RPM) system for respiratory gating based on breathing amplitude. Breathing traces were acquired from ten patients using two kinds of breathing patterns: free breathing and an interrupted (~ 5 s pause) end of exhale coached breathing pattern. Ion chamber and Gafchromic film measurements were acquired for a gated delivery while the phantom moved under the described breathing patterns, as well as for a nongated stationary phantom delivery. The gate window was set to obtain a range of residual target motion from 2-5 mm. All gated deliveries on a moving phantom have been shown to be dosimetrically equivalent to the nongated deliveries on a static phantom, with differences in point dose measurements under 1% and average gamma 2%/2 mm agreement above 98.7%. Comparison with the treatment planning system also resulted in good agreement, with differences in point-dose measurements under 2.5% and average gamma 3%/3 mm agreement of 97%. The use of a coached breathing pattern significantly increases the duty cycle, compared with free breathing, and allows for shorter treatment times. Patients' free-breathing patterns contain considerable variability and, although dosimetric results for gated delivery may be acceptable, it is difficult to achieve efficient treatment delivery. A coached breathing pattern combined with a 5 mm amplitude gate, resulted in both high-quality dose distributions and overall shortest gated beam delivery times.

  15. Amplitude gating for a coached breathing approach in respiratory gated 10 MV flattening filter-free VMAT delivery.

    PubMed

    Viel, Francis; Lee, Richard; Gete, Ermias; Duzenli, Cheryl

    2015-01-01

    The purpose of this study was to investigate amplitude gating combined with a coached breathing strategy for 10 MV flattening filter-free (FFF) volumetric-modulated arc therapy (VMAT) on the Varian TrueBeam linac. Ten patient plans for VMAT SABR liver were created using the Eclipse treatment planning system (TPS). The verification plans were then transferred to a CT-scanned Quasar phantom and delivered on a TrueBeam linac using a 10 MV FFF beam and Varian's real-time position management (RPM) system for respiratory gating based on breathing amplitude. Breathing traces were acquired from ten patients using two kinds of breathing patterns: free breathing and an interrupted (~ 5 s pause) end of exhale coached breathing pattern. Ion chamber and Gafchromic film measurements were acquired for a gated delivery while the phantom moved under the described breathing patterns, as well as for a nongated stationary phantom delivery. The gate window was set to obtain a range of residual target motion from 2-5 mm. All gated deliveries on a moving phantom have been shown to be dosimetrically equivalent to the nongated deliveries on a static phantom, with differences in point dose measurements under 1% and average gamma 2%/2 mm agreement above 98.7%. Comparison with the treatment planning system also resulted in good agreement, with differences in point-dose measurements under 2.5% and average gamma 3%/3 mm agreement of 97%. The use of a coached breathing pattern significantly increases the duty cycle, compared with free breathing, and allows for shorter treatment times. Patients' free-breathing patterns contain considerable variability and, although dosimetric results for gated delivery may be acceptable, it is difficult to achieve efficient treatment delivery. A coached breathing pattern combined with a 5 mm amplitude gate, resulted in both high-quality dose distributions and overall shortest gated beam delivery times. PMID:26219000

  16. Analysis of coordination between breathing and walking rhythms in humans.

    PubMed

    Rassler, B; Kohl, J

    1996-12-01

    We investigated the coordination between breathing and walking in humans to elucidate whether the coordination degree depends more on metabolic load or on breathing or stride frequencies and whether coordination causes energetic economization expressed by reduction of oxygen uptake (VO2). Eighteen healthy volunteers walked on a treadmill at three load levels realized by different velocities and slopes. We analyzed the time intervals between step onset and the onset of inspiration or expiration related to stride duration (relative phase, phi) and computed the relative-phase histogram to assess the degree of coordination. The degree of coordination between breathing and stepping enhanced with increasing walking speed. Increased work load achieved by slope at constant walking speed improved coordination only slightly. No significant VO2 reduction due to coordination was found. VO2 was more strongly related to ventilation variations occurring during coordination. Also the sympathetic tone reflected by the spectral power of heart rate variability was not reduced during coordination. We conclude that during walking the coordination degree increases with increasing stride frequency and that coordination does not necessarily cause energetic economization.

  17. Take a breath and take the turn: how breathing meets turns in spontaneous dialogue

    PubMed Central

    Rochet-Capellan, Amélie; Fuchs, Susanne

    2014-01-01

    Physiological rhythms are sensitive to social interactions and could contribute to defining social rhythms. Nevertheless, our knowledge of the implications of breathing in conversational turn exchanges remains limited. In this paper, we addressed the idea that breathing may contribute to timing and coordination between dialogue partners. The relationships between turns and breathing were analysed in unconstrained face-to-face conversations involving female speakers. No overall relationship between breathing and turn-taking rates was observed, as breathing rate was specific to the subjects' activity in dialogue (listening versus taking the turn versus holding the turn). A general inter-personal coordination of breathing over the whole conversation was not evident. However, specific coordinative patterns were observed in shorter time-windows when participants engaged in taking turns. The type of turn-taking had an effect on the respective coordination in breathing. Most of the smooth and interrupted turns were taken just after an inhalation, with specific profiles of alignment to partner breathing. Unsuccessful attempts to take the turn were initiated late in the exhalation phase and with no clear inter-personal coordination. Finally, breathing profiles at turn-taking were different than those at turn-holding. The results support the idea that breathing is actively involved in turn-taking and turn-holding. PMID:25385777

  18. Active breathing control (ABC): Determination and reduction of breathing-induced organ motion in the chest

    SciTech Connect

    Gagel, Bernd . E-mail: BGagel@UKAachen.de; Demirel, Cengiz M.P.; Kientopf, Aline; Pinkawa, Michael; Piroth, Marc; Stanzel, Sven; Breuer, Christian; Asadpour, Branka; Jansen, Thomas; Holy, Richard; Wildberger, Joachim E.; Eble, Michael J.

    2007-03-01

    Purpose: Extensive radiotherapy volumes for tumors of the chest are partly caused by interfractional organ motion. We evaluated the feasibility of respiratory observation tools using the active breathing control (ABC) system and the effect on breathing cycle regularity and reproducibility. Methods and Materials: Thirty-six patients with unresectable tumors of the chest were selected for evaluation of the ABC system. Computed tomography scans were performed at various respiratory phases starting at the same couch position without patient movement. Threshold levels were set at minimum and maximum volume during normal breathing cycles and at a volume defined as shallow breathing, reflecting the subjective maximal tolerable reduction of breath volume. To evaluate the extent of organ movement, 13 landmarks were considering using commercial software for image coregistration. In 4 patients, second examinations were performed during therapy. Results: Investigating the differences in a normal breathing cycle versus shallow breathing, a statistically significant reduction of respiratory motion in the upper, middle, and lower regions of the chest could be detected, representing potential movement reduction achieved through reduced breath volume. Evaluating interfraction reproducibility, the mean displacement ranged between 0.24 mm (chest wall/tracheal bifurcation) to 3.5 mm (diaphragm) for expiration and shallow breathing and 0.24 mm (chest wall) to 5.25 mm (diaphragm) for normal inspiration. Conclusions: By modifying regularity of the respiratory cycle through reduction of breath volume, a significant and reproducible reduction of chest and diaphragm motion is possible, enabling reduction of treatment planning margins.

  19. Take a breath and take the turn: how breathing meets turns in spontaneous dialogue.

    PubMed

    Rochet-Capellan, Amélie; Fuchs, Susanne

    2014-12-19

    Physiological rhythms are sensitive to social interactions and could contribute to defining social rhythms. Nevertheless, our knowledge of the implications of breathing in conversational turn exchanges remains limited. In this paper, we addressed the idea that breathing may contribute to timing and coordination between dialogue partners. The relationships between turns and breathing were analysed in unconstrained face-to-face conversations involving female speakers. No overall relationship between breathing and turn-taking rates was observed, as breathing rate was specific to the subjects' activity in dialogue (listening versus taking the turn versus holding the turn). A general inter-personal coordination of breathing over the whole conversation was not evident. However, specific coordinative patterns were observed in shorter time-windows when participants engaged in taking turns. The type of turn-taking had an effect on the respective coordination in breathing. Most of the smooth and interrupted turns were taken just after an inhalation, with specific profiles of alignment to partner breathing. Unsuccessful attempts to take the turn were initiated late in the exhalation phase and with no clear inter-personal coordination. Finally, breathing profiles at turn-taking were different than those at turn-holding. The results support the idea that breathing is actively involved in turn-taking and turn-holding.

  20. Delayed feedback applied to breathing in humans

    NASA Astrophysics Data System (ADS)

    Janson, N. B.; Pototsky, A.; Parkes, C.

    2013-10-01

    We studied the response of healthy volunteers to the delayed feedback generated from the breathing signals. Namely, in the freely-breathing volunteers the breathing signal was recorded, delayed by τ seconds and fed back to the same volunteer in real time in the form of a visual and auditory stimulus of low intensity, i.e. the stimulus was crucially non-intrusive. In each case volunteers were instructed to breathe in the way which was most comfortable for them, and no explanation about the kind of applied stimulus was provided to them. Each volunteer experienced 10 different delay times ranging between 10% and 100% of the average breathing period without external stimulus. It was observed that in a significant proportion of subjects (11 out of 24) breathing was slowed down in the presence of delayed feedback with moderate delay. Also, in 6 objects out of 24 the delayed feedback was able to induce transition from nearly periodic to irregular breathing. These observations are consistent with the phenomena observed in numerical simulation of the models of periodic and chaotic self-oscillations with delays, and also in experiments with simpler self-oscillating systems.

  1. An ultrasonic contactless sensor for breathing monitoring.

    PubMed

    Arlotto, Philippe; Grimaldi, Michel; Naeck, Roomila; Ginoux, Jean-Marc

    2014-01-01

    The monitoring of human breathing activity during a long period has multiple fundamental applications in medicine. In breathing sleep disorders such as apnea, the diagnosis is based on events during which the person stops breathing for several periods during sleep. In polysomnography, the standard for sleep disordered breathing analysis, chest movement and airflow are used to monitor the respiratory activity. However, this method has serious drawbacks. Indeed, as the subject should sleep overnight in a laboratory and because of sensors being in direct contact with him, artifacts modifying sleep quality are often observed. This work investigates an analysis of the viability of an ultrasonic device to quantify the breathing activity, without contact and without any perception by the subject. Based on a low power ultrasonic active source and transducer, the device measures the frequency shift produced by the velocity difference between the exhaled air flow and the ambient environment, i.e., the Doppler effect. After acquisition and digitization, a specific signal processing is applied to separate the effects of breath from those due to subject movements from the Doppler signal. The distance between the source and the sensor, about 50 cm, and the use of ultrasound frequency well above audible frequencies, 40 kHz, allow monitoring the breathing activity without any perception by the subject, and therefore without any modification of the sleep quality which is very important for sleep disorders diagnostic applications. This work is patented (patent pending 2013-7-31 number FR.13/57569). PMID:25140632

  2. Immediate effects of breath holding maneuvers onto composition of exhaled breath.

    PubMed

    Sukul, Pritam; Trefz, Phillip; Schubert, Jochen K; Miekisch, Wolfram

    2014-09-01

    Rapid concentration changes due to physiological or pathophysiological effects rather than appearance of unique disease biomarkers are important for clinical application of breath research. Simple maneuvers such as breath holding may significantly affect breath biomarker concentrations. In this study, exhaled volatile organic compound (VOC) concentrations were assessed in real time before and after different breath holding maneuvers. Continuous breath-resolved measurements (PTR-ToF-MS-8000) were performed in 31 healthy human subjects in a side-stream sampling mode. After 1 min of tidal breathing participants held their breath for 10, 20, 40, 60 s and as long as possible. Afterwards they continued to breathe normally for another minute. VOC profiles could be monitored in real time by assigning online PTR-ToF-MS data to alveolar or inspired phases of breath. Sudden and profound changes of exhaled VOC concentrations were recorded after different breath holding maneuvers. VOC concentrations returned to base line levels 10-20 s after breath holding. Breath holding induced concentration changes depended on physico-chemical properties of the substances. When substance concentrations were normalized onto end-tidal CO2 content, variation of acetone concentrations decreased, whereas variations of isoprene concentrations were not affected. As the effects of breathing patterns on exhaled substance concentrations depend on individual substance properties, sampling procedures have to be validated for each compound by means of appropriate real-time analysis. Normalization of exhaled concentrations onto exhaled CO2 is only valid for substances having similar physico-chemical properties as CO2.

  3. The technology of metered-dose inhalers and treatment costs in asthma: a retrospective study of breath actuation versus traditional press-and-breathe inhalers.

    PubMed

    Langley, P C

    1999-01-01

    This paper reviews the impact of the use of technologically dissimilar beta-agonist aerosols--the Maxair Autohaler (pirbuterol acetate) breath-actuated aerosol and the traditional albuterol press-and-breathe inhaler-on the treatment costs of asthma. If, as clinical evidence would suggest, the breath-actuated aerosol is not only as effective as an albuterol inhaler with a spacer, but is easier to use and results in more optimal beta-agonist use by patients, then one might consider the hypothesis that patients possessing a breath-actuated inhaler would, ceteris paribus, experience lower asthma-related treatment costs-principally, those medical costs associated with fewer emergency room visits and hospitalizations. This hypothesis is considered from the perspective of a retrospective claims database study of patients who used one or the other beta-agonist inhaler exclusively. At the descriptive level, costs of treatment for patients using the press-and-breathe inhaler are estimated to be 16.5% greater than costs for patients using the breath-actuated inhaler. In the multivariate analysis, the presence of the breath-actuated inhaler (in a dummy variable analysis) was not only statistically significant (P < 0.05), but entered with the expected negative sign. Estimated cost impacts under various model specifications are consistent with the magnitude of the cost differences reported in the descriptive analysis. Total cost savings with the Maxair Autohaler ranged from 8.7% to 11.7%, with medical cost savings estimated at 14.6%. PMID:10090438

  4. Cardiovascular Disease and Diabetes

    MedlinePlus

    ... Blood Pressure Tools & Resources Stroke More Cardiovascular Disease & Diabetes Updated:Mar 23,2016 The following statistics speak ... disease. This content was last reviewed August 2015. Diabetes • Home • About Diabetes • Why Diabetes Matters Introduction Cardiovascular ...

  5. Infection and Cardiovascular Disease

    ClinicalTrials.gov

    2016-02-17

    Cardiovascular Diseases; Coronary Disease; Cerebrovascular Accident; Heart Diseases; Myocardial Infarction; Infection; Chlamydia Infections; Cytomegalovirus Infections; Helicobacter Infections; Atherosclerosis

  6. Comparison of exhaled nitric oxide and cardiorespiratory indices between nasal and oral breathing during submaximal exercise in humans.

    PubMed

    Yasuda, Y; Itoh, T; Miyamura, M; Nishino, H

    1997-10-01

    In order to examine the origin and role of nitric oxide (NO) in exhaled air during exercise, exhaled NO outputs of 8 healthy human subjects were compared using different breathing methods, through the mouth or nose, at two intensities of bicycle exercise. The concentration of NO in the exhaled air and ventilatory gas exchange variables were measured by a chemiluminescence analyzer and a mixing chamber method, respectively. The concentration and total output of NO in the expired air was significantly higher under nasal breathing than under oral breathing for both exercise intensities, whereas no significant difference was observed in cardiorespiratory variables between them. NO output increased significantly when exercise intensity was increased from unloaded (0 W) to 60 W under nasal breathing, but not under oral breathing. A negative correlation among subjects was found between NO output and minute ventilation in both breathing methods only for unloaded exercise. Data indicate that nasal airways have a large contribution, at least 50% of total NO output in the exhaled air during nasal breathing, but this nasal NO may have no further modulation on respiratory function during submaximal exercise by healthy humans.

  7. Heart rate variability in normal and pathological sleep

    PubMed Central

    Tobaldini, Eleonora; Nobili, Lino; Strada, Silvia; Casali, Karina R.; Braghiroli, Alberto; Montano, Nicola

    2013-01-01

    Sleep is a physiological process involving different biological systems, from molecular to organ level; its integrity is essential for maintaining health and homeostasis in human beings. Although in the past sleep has been considered a state of quiet, experimental and clinical evidences suggest a noteworthy activation of different biological systems during sleep. A key role is played by the autonomic nervous system (ANS), whose modulation regulates cardiovascular functions during sleep onset and different sleep stages. Therefore, an interest on the evaluation of autonomic cardiovascular control in health and disease is growing by means of linear and non-linear heart rate variability (HRV) analyses. The application of classical tools for ANS analysis, such as HRV during physiological sleep, showed that the rapid eye movement (REM) stage is characterized by a likely sympathetic predominance associated with a vagal withdrawal, while the opposite trend is observed during non-REM sleep. More recently, the use of non-linear tools, such as entropy-derived indices, have provided new insight on the cardiac autonomic regulation, revealing for instance changes in the cardiovascular complexity during REM sleep, supporting the hypothesis of a reduced capability of the cardiovascular system to deal with stress challenges. Interestingly, different HRV tools have been applied to characterize autonomic cardiac control in different pathological conditions, from neurological sleep disorders to sleep disordered breathing (SDB). In summary, linear and non-linear analysis of HRV are reliable approaches to assess changes of autonomic cardiac modulation during sleep both in health and diseases. The use of these tools could provide important information of clinical and prognostic relevance. PMID:24137133

  8. Measurement of low breath-alcohol concentrations: laboratory studies and field experience.

    PubMed

    Dubowski, K M; Essary, N A

    1999-10-01

    Recent federal rules and traffic law changes impose breath-alcohol thresholds of 0.02 and 0.04 g/210 L upon some classes of motor vehicle operators, such as juveniles and commercial vehicle operators. In federally regulated alcohol testing in the workplace, removal of covered workers from safety-sensitive duties, and other adverse actions, also occur at breath-alcohol concentrations (BrACs) of 0.02 and 0.04 g/210 L. We therefore studied performance of vapor-alcohol and breath-alcohol measurement at low alcohol concentrations in the laboratory and in the field, with current-generation evidential analyzers. We report here chiefly our field experience with evidential breath-alcohol testing of drinking drivers on paired breath samples using 62 Intoxilyzer 5000-D analyzers, for BrACs of 0-0.059 g/210 L. The data from 62 law enforcement breath-alcohol testing sites were collected and pooled, with BrACs recorded to three decimal places, and otherwise carried out under the standard Oklahoma evidential breath-alcohol testing protocol. For 2105 pooled simulator control tests at 0.06-0.13 g/210 L the mean +/- SD of the differences between target and result were -0.001 +/- 0.0035 g/210 L and 0.003 +/- 0.0023 g/210 L for signed and absolute differences, respectively (spans -0.016-0.010, 0.000-0.016). For 2078 paired duplicate breath-alcohol measurements with the Intoxilyzer 5000-D, the mean +/- SD difference (BrAC1-BrAC2) were 0.002 +/- 0.0026 (span 0-0.020 g/210 L). Variability of breath-alcohol measurements was related inversely to the alcohol concentration. Ninety-nine percent prediction limits for paired BrAC measurements correspond to a 0.020 g/210 L maximum absolute difference, meeting the NSC/CAOD recommendation that paired breath-alcohol analysis results within 0.02 g/210 L shall be deemed to be in acceptable agreement. We conclude that the field system for breath-alcohol analysis studied by us can and does perform reliably and accurately at low BrACs.

  9. 21 CFR 862.3050 - Breath-alcohol test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breath-alcohol test system. 862.3050 Section 862....3050 Breath-alcohol test system. (a) Identification. A breath-alcohol test system is a device intened to measure alcohol in the human breath. Measurements obtained by this device are used in...

  10. 21 CFR 862.3050 - Breath-alcohol test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breath-alcohol test system. 862.3050 Section 862....3050 Breath-alcohol test system. (a) Identification. A breath-alcohol test system is a device intened to measure alcohol in the human breath. Measurements obtained by this device are used in...

  11. 21 CFR 862.3050 - Breath-alcohol test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breath-alcohol test system. 862.3050 Section 862....3050 Breath-alcohol test system. (a) Identification. A breath-alcohol test system is a device intened to measure alcohol in the human breath. Measurements obtained by this device are used in...

  12. 21 CFR 862.3050 - Breath-alcohol test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breath-alcohol test system. 862.3050 Section 862....3050 Breath-alcohol test system. (a) Identification. A breath-alcohol test system is a device intened to measure alcohol in the human breath. Measurements obtained by this device are used in...

  13. 21 CFR 862.3050 - Breath-alcohol test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breath-alcohol test system. 862.3050 Section 862....3050 Breath-alcohol test system. (a) Identification. A breath-alcohol test system is a device intened to measure alcohol in the human breath. Measurements obtained by this device are used in...

  14. 42 CFR 84.72 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tubes; minimum requirements. 84.72 Section 84.72 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL...-Contained Breathing Apparatus § 84.72 Breathing tubes; minimum requirements. Flexible breathing tubes...

  15. 42 CFR 84.72 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tubes; minimum requirements. 84.72 Section 84.72 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL...-Contained Breathing Apparatus § 84.72 Breathing tubes; minimum requirements. Flexible breathing tubes...

  16. 42 CFR 84.72 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tubes; minimum requirements. 84.72 Section 84.72 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL...-Contained Breathing Apparatus § 84.72 Breathing tubes; minimum requirements. Flexible breathing tubes...

  17. 42 CFR 84.72 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.72 Section 84.72 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL...-Contained Breathing Apparatus § 84.72 Breathing tubes; minimum requirements. Flexible breathing tubes...

  18. 42 CFR 84.72 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tubes; minimum requirements. 84.72 Section 84.72 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL...-Contained Breathing Apparatus § 84.72 Breathing tubes; minimum requirements. Flexible breathing tubes...

  19. Portable breathing apparatus for coal mines

    NASA Technical Reports Server (NTRS)

    Vandolah, R. W.

    1972-01-01

    The state of the art in portable oxygen breathing equipment is reported. Considered are self-containing as well as chemically generating oxygen sources and their effectiveness and limitations in mine rescue operations.

  20. Coordination of Mastication, Swallowing and Breathing

    PubMed Central

    Matsuo, Koichiro; Palmer, Jeffrey B.

    2009-01-01

    Summary The pathways for air and food cross in the pharynx. In breathing, air may flow through either the nose or the mouth, it always flows through the pharynx. During swallowing, the pharynx changes from an airway to a food channel. The pharynx is isolated from the nasal cavity and lower airway by velopharyngeal and laryngeal closure during the pharyngeal swallow. During mastication, the food bolus accumulates in the pharynx prior to swallow initiation. The structures in the oral cavity, pharynx and larynx serve multiple functions in breathing, speaking, mastication and swallowing. Thus, the fine temporal coordination of feeding among breathing, mastication and swallowing is essential to provide proper food nutrition and to prevent pulmonary aspiration. This review paper will review the temporo-spatial coordination of the movements of oral, pharyngeal, and laryngeal structures during mastication and swallowing, and temporal coordination between breathing, mastication, and swallowing. PMID:20161022

  1. Does a Smaller Waist Mean Smelly Breath?

    MedlinePlus

    ... overnight on the surface of the tongue when saliva production is diminished." ; Tips to combat halitosis: ; 1. Drink ... after meals can help keep bad breath away. Saliva production increases during chewing and this can help neutralize ...

  2. Alcohol breath test: gas exchange issues.

    PubMed

    Hlastala, Michael P; Anderson, Joseph C

    2016-08-01

    The alcohol breath test is reviewed with a focus on gas exchange factors affecting its accuracy. The basis of the alcohol breath test is the assumption that alveolar air reaches the mouth during exhalation with no change in alcohol concentration. Recent investigations have shown that alcohol concentration is altered during its transit to the mouth. The exhaled alcohol concentration is modified by interaction with the mucosa of the pulmonary airways. Exhaled alcohol concentration is not an accurate indicator of alveolar alcohol concentration. Measuring alcohol concentration in the breath is very different process than measuring a blood level from air equilibrated with a blood sample. Airway exchange of alcohol leads to a bias against certain individuals depending on the anatomic and physiologic characteristics. Methodological modifications are proposed to improve the accuracy of the alcohol breath test to become fair to all. PMID:27197859

  3. Haemoptysis after breath-hold diving.

    PubMed

    Boussuges, A; Pinet, C; Thomas, P; Bergmann, E; Sainty, J M; Vervloet, D

    1999-03-01

    Pulmonary oedema has been described in swimmers and self-contained underwater breathing apparatus (Scuba) divers. This study reports three cases of haemoptysis secondary to alveolar haemorrhage in breath-hold divers. Contributory factors, such as haemodynamic modifications secondary to immersion, cold exposure, exercise and exposure to an increase in ambient pressure, could explain this type of accident. Furthermore, these divers had taken aspirin, which may have aggravated the bleeding.

  4. VARIATION OF LUNG DEPOSITION OF MICRON SIZE PARTICLES WITH LUNG VOLUME AND BREATHING PATTERN

    EPA Science Inventory

    Lung volume and breathing pattern are the source of inter-and intra-subject variability of lung deposition of inhaled particles. Controlling these factors may help optimize delivery of aerosol medicine to the target site within the lung. In the present study we measured total lu...

  5. Extreme human breath-hold diving.

    PubMed

    Ferretti, G

    2001-04-01

    In this paper, the respiratory, circulatory and metabolic adjustments to human extreme breath-hold diving are reviewed. A survey of the literature reveals that in extreme divers, adaptive mechanisms take place that allow prolongation of apnoea beyond the limits attained by non-diving subjects, and preservation of oxygen stores during the dives. The occurrence of a diving response, including peripheral vasoconstriction, increased arterial blood pressure, bradycardia and lowered cardiac output, is strongly implicated. Some peripheral regions may be excluded from perfusion, with consequent reliance on anaerobic metabolism. In addition, extreme breath-hold divers show a blunted ventilatory response to carbon dioxide breathing, possibly as a consequence of frequent exposure to high carbon dioxide partial pressures during the dives. These mechanisms allow the attainment of particularly low alveolar oxygen (< 30 mmHg) and high alveolar carbon dioxide (> 50 mmHg) partial pressures at the end of maximal dry breath-holds, and reduce oxygen consumption during the dive at the expense of increased anaerobic glycolysis (rate of blood lactate accumulation > 0.04 mM.s-1). The current absolute world record for depth in breath-hold diving is 150 m. Its further improvement depends upon how far the equilibrium between starting oxygen stores, the overall rate of energy expenditure, the fraction of energy provided by anaerobic metabolism and the diving speed can be pushed, with consciousness upon emersion. The ultimate limit to breath-hold diving records may indeed be imposed by an energetic constraint. PMID:11374109

  6. Monitoring breath markers under controlled conditions.

    PubMed

    Righettoni, Marco; Ragnoni, Alessandro; Güntner, Andreas T; Loccioni, Claudio; Pratsinis, Sotiris E; Risby, Terence H

    2015-12-01

    Breath analysis has the potential to detect and monitor diseases as well as to reduce the corresponding medical costs while improving the quality of a patient's life. Herein, a portable prototype, consisting of a commercial breath sampler modified to work as a platform for solid-state gas sensors was developed. The sensor is placed close to the mouth (<10 cm) and minimizes the mouth-to-sensor path to avoid contamination and dilution of the target breath marker. Additionally with an appropriate cooling concept, even high sensor operating temperatures (e.g. 350 °C) could be used. Controlled sampling is crucial for accurate repeatable analysis of the human breath and these concerns have been addressed by this novel prototype. The device helps a subject control their exhaled flow rate which increases reproducibility of intra-subject breath samples. The operation of this flame-made selective chemo-resistive gas sensor is demonstrated by the detection of breath acetone. PMID:26469378

  7. Hydrogen breath tests in gastrointestinal diseases.

    PubMed

    Rana, Satya Vati; Malik, Aastha

    2014-10-01

    Hydrogen breath tests are widely used to explore pathophysiology of functional gastrointestinal (GI) disorders. Small intestinal bacterial overgrowth (SIBO) and carbohydrate malabsorption are disorders detected by these tests that have been proposed to be of great importance for symptoms of GI diseases. Glucose hydrogen breath test is more acceptable for diagnosis of SIBO whereas lactose and fructose hydrogen breath tests are used for detection of lactose and fructose maldigestion respectively. Lactulose hydrogen breath test is also used widely to measure the orocecal transit time for GI motility. These methods are noninvasive and inexpensive. Many patients with functional gut disorders are unaware of the relationship between diet and GI symptoms they present. In particular, patients with chronic symptoms may regard their condition as normal and may not be aware that their symptoms can be effectively managed following a proper diagnosis. Patients with symptoms of abdominal pain, bloating, flatulence and altered bowel movements (diarrhea and constipation), or with a medical diagnosis of irritable bowel syndrome or celiac disease, may have undiagnosed carbohydrate malabsorption or SIBO. Hydrogen breath tests are specific and sensitive diagnostic tests that can be used to either confirm or eliminate the possibility of carbohydrate malabsorption or SIBO in such patients. Breath tests, though valuable tools, are underutilized in evaluating dyspepsia and functional bloating and diarrhea as well as suspected malabsorption. However, because of their simplicity, reproducibility and safety of procedure they are now being substituted to more uncomfortable and expensive techniques that were traditionally used in gastroenterology. PMID:25298621

  8. Optoacoustic 13C-breath test analyzer

    NASA Astrophysics Data System (ADS)

    Harde, Hermann; Helmrich, Günther; Wolff, Marcus

    2010-02-01

    The composition and concentration of exhaled volatile gases reflects the physical ability of a patient. Therefore, a breath analysis allows to recognize an infectious disease in an organ or even to identify a tumor. One of the most prominent breath tests is the 13C-urea-breath test, applied to ascertain the presence of the bacterium helicobacter pylori in the stomach wall as an indication of a gastric ulcer. In this contribution we present a new optical analyzer that employs a compact and simple set-up based on photoacoustic spectroscopy. It consists of two identical photoacoustic cells containing two breath samples, one taken before and one after capturing an isotope-marked substrate, where the most common isotope 12C is replaced to a large extent by 13C. The analyzer measures simultaneously the relative CO2 isotopologue concentrations in both samples by exciting the molecules on specially selected absorption lines with a semiconductor laser operating at a wavelength of 2.744 μm. For a reliable diagnosis changes of the 13CO2 concentration of 1% in the exhaled breath have to be detected at a concentration level of this isotope in the breath of about 500 ppm.

  9. Control of breathing in invertebrate model systems.

    PubMed

    Bell, Harold J; Syed, Naweed I

    2012-07-01

    The invertebrates have adopted a myriad of breathing strategies to facilitate the extraction of adequate quantities of oxygen from their surrounding environments. Their respiratory structures can take a wide variety of forms, including integumentary surfaces, lungs, gills, tracheal systems, and even parallel combinations of these same gas exchange structures. Like their vertebrate counterparts, the invertebrates have evolved elaborate control strategies to regulate their breathing activity. Our goal in this article is to present the reader with a description of what is known regarding the control of breathing in some of the specific invertebrate species that have been used as model systems to study different mechanistic aspects of the control of breathing. We will examine how several species have been used to study fundamental principles of respiratory rhythm generation, central and peripheral chemosensory modulation of breathing, and plasticity in the control of breathing. We will also present the reader with an overview of some of the behavioral and neuronal adaptability that has been extensively documented in these animals. By presenting explicit invertebrate species as model organisms, we will illustrate mechanistic principles that form the neuronal foundation of respiratory control, and moreover appear likely to be conserved across not only invertebrates, but vertebrate species as well. PMID:23723022

  10. Operational point of neural cardiovascular regulation in humans up to 6 months in space.

    PubMed

    Verheyden, B; Liu, J; Beckers, F; Aubert, A E

    2010-03-01

    Entering weightlessness affects central circulation in humans by enhancing venous return and cardiac output. We tested whether the operational point of neural cardiovascular regulation in space sets accordingly to adopt a level close to that found in the ground-based horizontal position. Heart rate (HR), finger blood and brachial blood pressure (BP), and respiratory frequency were collected in 11 astronauts from nine space missions. Recordings were made in supine and standing positions at least 10 days before launch and during spaceflight (days 5-19, 45-67, 77-116, 146-180). Cross-correlation analyses of HR and systolic BP were used to measure three complementary aspects of cardiac baroreflex modulation: 1) baroreflex sensitivity, 2) number of effective baroreflex estimates, and 3) baroreflex time delay. A fixed breathing protocol was performed to measure respiratory sinus arrhythmia and low-frequency power of systolic BP variability. We found that HR and mean arterial pressure did not differ from preflight supine values for up to 6 mo in space. Respiration frequency tended to decrease during prolonged spaceflight. Concerning neural markers of cardiovascular regulation, we observed in-flight adaptations toward homeostatic conditions similar to those found in the ground-based supine position. Surprisingly, this was not the case for baroreflex time delay distribution, which had somewhat longer latencies in space. Except for this finding, our results confirm that the operational point of neural cardiovascular regulation in space sets to a level close to that of an Earth-based supine position. This adaptation level suggests that circulation is chronically relaxed for at least 6 mo in space. PMID:20075261

  11. Cardiac or Other Implantable Electronic Devices and Sleep-disordered Breathing – Implications for Diagnosis and Therapy

    PubMed Central

    Bitter, Thomas; Gutleben, Klaus-Jürgen; Horstkotte, Dieter; Oldenburg, Olaf

    2014-01-01

    Sleep-disordered breathing (SDB) is of growing interest in cardiology because SDB is a highly prevalent comorbidity in patients with a variety of cardiovascular diseases. The prevalence of SDB is particularly high in patients with cardiac dysrhythmias and/or heart failure. In this setting, many patients now have implantable cardiac devices, such as pacemakers, implantable cardioverter-defibrillators or implanted cardiac resynchronisation therapy devices (CRT). Treatment of SDB using implantable cardiac devices has been studied previously, with atrial pacing and CRT being shown not to bring about satisfactory results in SDB care. The latest generations of these devices have the capacity to determine transthoracic impedance, to detect and quantify breathing efforts and to identify SDB. The capability of implantable cardiac devices to detect SDB is of potential importance for patients with cardiovascular disease, allowing screening for SDB, monitoring of the course of SDB in relation to cardiac status, and documenting of the effects of treatment. PMID:26835077

  12. Underwater Stroke Kinematics During Breathing and Breath-holding Front Crawl Swimming.

    PubMed

    Vezos, Nickos; Gourgoulis, Vassilios; Aggeloussis, Nickos; Kasimatis, Panagiotis; Christoforidis, Christos; Mavromatis, Giorgos

    2007-01-01

    The aim of the present study was to determine the effects of breathing on the three - dimensional underwater stroke kinematics of front crawl swimming. Ten female competitive freestyle swimmers participated in the study. Each subject swam a number of front crawl trials of 25 m at a constant speed under breathing and breath-holding conditions. The underwater motion of each subject's right arm was filmed using two S-VHS cameras, operating at 60 Hz, which were positioned behind two underwater viewing windows. The spatial coordinates of selected points were calculated using the DLT procedure with 30 control points and after the digital filtering of the raw data with a cut-off frequency of 6 Hz, the hand's linear displacements and velocities were calculated. The results revealed that breathing caused significantly increases in the stroke duration (t9 = 2.764; p < 0.05), the backward hand displacement relative to the water (t9 = 2.471; p<0.05) and the lateral displacement of the hand in the X - axis during the downsweep (t9 = 2.638; p < 0.05). On the contrary, the peak backward hand velocity during the insweep (t9 = 2.368; p < 0.05) and the displacement of the hand during the push phase (t9 = -2.297; p < 0.05) were greatly reduced when breathing was involved. From the above, it was concluded that breathing action in front crawl swimming caused significant modifications in both the basic stroke parameters and the overall motor pattern were, possibly due to body roll during breathing. Key pointsThe breathing action increases the duration of the total underwater pull.The breathing action increases the absolute backward displacement of the hand.The breathing action caused significant modifications in the overall motor pattern, possibly due to body roll during breathing. PMID:24149225

  13. Upper limb kinematic differences between breathing and non-breathing conditions in front crawl sprint swimming.

    PubMed

    McCabe, Carla B; Sanders, Ross H; Psycharakis, Stelios G

    2015-11-26

    The purpose of this study was to determine whether the breathing action in front crawl (FC) sprint swimming affects the ipsilateral upper limb kinematics relative to a non-breathing stroke cycle (SC). Ten male competitive swimmers performed two 25m FC sprints: one breathing to their preferred side (Br) and one not breathing (NBr). Both swim trials were performed through a 6.75m(3) calibrated space and recorded by six gen-locked JVC KY32 CCD cameras. A paired t-test was used to assess statistical differences between the trials, with a confidence level of p<0.05 accepted as significant. Swimmers were slower (3%) when breathing. Within the entry phase, swimmers had a slower COM horizontal velocity (3.3%), less shoulder flexion (8%), abduction (33%) and roll (4%) when breathing. The pull phase was longer in duration (14%) swimmers had a shallower hand path (11%), less shoulder abduction (11%), a slower hand vertical acceleration (30%) and slower centre of mass (COM) horizontal velocity (3%) when breathing. In the push phase, swimmers had a smaller elbow range of motion (ROM) (38%), faster backwards hand speed (25%) and faster hand vertical acceleration (33%) when breathing. Swimmers rolled their shoulders more (12%) in the recovery phase when breathing. This study confirms that swim performance is compromised by the inclusion of taking a breath in sprint FC swimming. It was proposed that swimmers aim to orient their ipsilateral shoulder into a stronger position by stretching and rolling the shoulders more in the entry phase whilst preparing to take a breath. Swimmers should focus on lengthening the push phase by extending the elbow more and not accelerating the hand too quickly upwards when preparing to inhale. PMID:26456423

  14. Upper limb kinematic differences between breathing and non-breathing conditions in front crawl sprint swimming.

    PubMed

    McCabe, Carla B; Sanders, Ross H; Psycharakis, Stelios G

    2015-11-26

    The purpose of this study was to determine whether the breathing action in front crawl (FC) sprint swimming affects the ipsilateral upper limb kinematics relative to a non-breathing stroke cycle (SC). Ten male competitive swimmers performed two 25m FC sprints: one breathing to their preferred side (Br) and one not breathing (NBr). Both swim trials were performed through a 6.75m(3) calibrated space and recorded by six gen-locked JVC KY32 CCD cameras. A paired t-test was used to assess statistical differences between the trials, with a confidence level of p<0.05 accepted as significant. Swimmers were slower (3%) when breathing. Within the entry phase, swimmers had a slower COM horizontal velocity (3.3%), less shoulder flexion (8%), abduction (33%) and roll (4%) when breathing. The pull phase was longer in duration (14%) swimmers had a shallower hand path (11%), less shoulder abduction (11%), a slower hand vertical acceleration (30%) and slower centre of mass (COM) horizontal velocity (3%) when breathing. In the push phase, swimmers had a smaller elbow range of motion (ROM) (38%), faster backwards hand speed (25%) and faster hand vertical acceleration (33%) when breathing. Swimmers rolled their shoulders more (12%) in the recovery phase when breathing. This study confirms that swim performance is compromised by the inclusion of taking a breath in sprint FC swimming. It was proposed that swimmers aim to orient their ipsilateral shoulder into a stronger position by stretching and rolling the shoulders more in the entry phase whilst preparing to take a breath. Swimmers should focus on lengthening the push phase by extending the elbow more and not accelerating the hand too quickly upwards when preparing to inhale.

  15. The fast exercise drive to breathe.

    PubMed

    Duffin, James

    2014-02-01

    This paper presents a personal view of research into the exercise drive to breathe that can be observed to act immediately to increase breathing at the start of rhythmic exercise. It is based on a talk given at the Experimental Biology 2013 meeting in a session entitled 'Recent advances in understanding mechanisms regulating breathing during exercise'. This drive to breathe has its origin in a combination of central command, whereby voluntary motor commands to the exercising muscles produce a concurrent respiratory drive, and afferent feedback, whereby afferent information from the exercising muscles affects breathing. The drive at the start and end of rhythmic exercise is proportional to limb movement frequency, and its magnitude decays as exercise continues so that the immediate decrease of ventilation at the end of exercise is about 60% of the immediate increase at the start. With such evidence for the effect of this fast drive to breathe at the start and end of rhythmic exercise, its existence during exercise is hypothesised. Experiments to test this hypothesis have, however, provided debatable evidence. A fast drive to breathe during both ramp and sine wave changes in treadmill exercise speed and grade appears to be present in some individuals, but is not as evident in the general population. Recent sine-wave cycling experiments show that when cadence is varied sinusoidally the ventilation response lags by about 10 s, whereas when pedal loading is varied ventilation lags by about 30 s. It therefore appears that limb movement frequency is effective in influencing ventilation during exercise as well as at the start and end of exercise. PMID:23940383

  16. The fast exercise drive to breathe.

    PubMed

    Duffin, James

    2014-02-01

    This paper presents a personal view of research into the exercise drive to breathe that can be observed to act immediately to increase breathing at the start of rhythmic exercise. It is based on a talk given at the Experimental Biology 2013 meeting in a session entitled 'Recent advances in understanding mechanisms regulating breathing during exercise'. This drive to breathe has its origin in a combination of central command, whereby voluntary motor commands to the exercising muscles produce a concurrent respiratory drive, and afferent feedback, whereby afferent information from the exercising muscles affects breathing. The drive at the start and end of rhythmic exercise is proportional to limb movement frequency, and its magnitude decays as exercise continues so that the immediate decrease of ventilation at the end of exercise is about 60% of the immediate increase at the start. With such evidence for the effect of this fast drive to breathe at the start and end of rhythmic exercise, its existence during exercise is hypothesised. Experiments to test this hypothesis have, however, provided debatable evidence. A fast drive to breathe during both ramp and sine wave changes in treadmill exercise speed and grade appears to be present in some individuals, but is not as evident in the general population. Recent sine-wave cycling experiments show that when cadence is varied sinusoidally the ventilation response lags by about 10 s, whereas when pedal loading is varied ventilation lags by about 30 s. It therefore appears that limb movement frequency is effective in influencing ventilation during exercise as well as at the start and end of exercise.

  17. The fast exercise drive to breathe

    PubMed Central

    Duffin, James

    2014-01-01

    This paper presents a personal view of research into the exercise drive to breathe that can be observed to act immediately to increase breathing at the start of rhythmic exercise. It is based on a talk given at the Experimental Biology 2013 meeting in a session entitled ‘Recent advances in understanding mechanisms regulating breathing during exercise’. This drive to breathe has its origin in a combination of central command, whereby voluntary motor commands to the exercising muscles produce a concurrent respiratory drive, and afferent feedback, whereby afferent information from the exercising muscles affects breathing. The drive at the start and end of rhythmic exercise is proportional to limb movement frequency, and its magnitude decays as exercise continues so that the immediate decrease of ventilation at the end of exercise is about 60% of the immediate increase at the start. With such evidence for the effect of this fast drive to breathe at the start and end of rhythmic exercise, its existence during exercise is hypothesised. Experiments to test this hypothesis have, however, provided debatable evidence. A fast drive to breathe during both ramp and sine wave changes in treadmill exercise speed and grade appears to be present in some individuals, but is not as evident in the general population. Recent sine-wave cycling experiments show that when cadence is varied sinusoidally the ventilation response lags by about 10 s, whereas when pedal loading is varied ventilation lags by about 30 s. It therefore appears that limb movement frequency is effective in influencing ventilation during exercise as well as at the start and end of exercise. PMID:23940383

  18. Cardiovascular issues in respiratory care.

    PubMed

    Pinsky, Michael R

    2005-11-01

    The hemodynamic effects of ventilation are complex but can be grouped under four clinically relevant concepts. First, spontaneous ventilation is exercise, and critically ill patients may not withstand the increased work of breathing. Initiation of mechanical ventilatory support will improve oxygen delivery to the remainder of the body by decreasing oxygen consumption. To the extent that mixed venous oxygen also increases, Pao(2) will increase without any improvement in gas exchange. Similarly, weaning from mechanical ventilatory support is a cardiovascular stress test. Patients who fail to wean also manifest cardiovascular insufficiency during the failed weaning attempts. Improving cardiovascular reserve or supplementing support with inotropic therapy may allow patients to wean from mechanical ventilation. Second, changes in lung volume alter autonomic tone and pulmonary vascular resistance (PVR), and at high lung volumes compress the heart in the cardiac fossa. Hyperinflation increases PVR and pulmonary artery pressure, impeding right ventricular ejection. Decreases in lung volume induce alveolar collapse and hypoxia, stimulating an increased pulmonary vasomotor tone by the process of hypoxic pulmonary vasoconstriction. Recruitment maneuvers, positive end-expiratory pressure, and continuous positive airway pressure may reverse hypoxic pulmonary vasoconstriction and reduce pulmonary artery pressure. Third, spontaneous inspiration and spontaneous inspiratory efforts decrease intrathoracic pressure (ITP). Since diaphragmatic descent increases intra-abdominal pressure, these combined effects cause right atrial pressure inside the thorax to decrease but venous pressure in the abdomen to increase, markedly increasing the pressure gradient for systemic venous return. Furthermore, the greater the decrease in ITP, the greater the increase in left ventricular (LV) afterload for a constant arterial pressure. Mechanical ventilation, by abolishing the negative swings in ITP

  19. Obesity and cardiovascular disease.

    PubMed

    Jokinen, E

    2015-02-01

    Cardiovascular disease is the most common cause of mortality in rich countries and today it has the same meaning for health care as the epidemics of past centuries had for medicine in earlier times: 50% of the population in these countries die of cardiovascular disease. The amount of cardiovascular disease is also increasing in the developing countries together with economic growth. By 2015 one in three deaths will globally be due to cardiovascular diseases. Coronary heart disease is a chronic disease that starts in childhood, even if the symptoms first occur in the middle age. The risks for coronary heart disease are well-known: lipid disorders, especially high serum LDL-cholesterol concentration, high blood pressure, tobacco smoking, obesity, diabetes, male gender and physical inactivity. Obesity is both an independent risk factor for cardiovascular disease but is also closely connected with several other risk factors. This review focuses on the connection between overweight or obesity and cardiovascular disease. PMID:25387321

  20. Additional work of breathing imposed by endotracheal tubes, breathing circuits, and intensive care ventilators.

    PubMed

    Bersten, A D; Rutten, A J; Vedig, A E; Skowronski, G A

    1989-07-01

    A disadvantage of spontaneous breathing through an endotracheal tube (ETT) and connector attached to a breathing circuit and/or ventilator (breathing device) is an increase in the work of breathing. The work of breathing associated with ETT of 6 to 9-mm diameter and eight breathing devices was determined, using a lung simulator to mimic spontaneous inspiration at flow rates of 20 to 100 L/min and a tidal volume of 500 ml, at both zero end-expiratory pressure (ZEEP) and 10 cm H2O continuous positive airway pressure (CPAP). Work associated with the breathing devices alone (WCIR) ranged from -0.002 kg.m/L (Servo 900-C ventilator, 7-mm ETT, 20 L/min, ZEEP) to 0.1 kg.m/L (continuous flow circuit, 7-mm ETT, 100 L/min, CPAP), the latter representing 196% of the work of normal breathing. When the devices were attached to ETT, total apparatus work (WAPP) ranged from 0.009 kg.m/L (Mapleson-D circuit, 9-mm ETT, 20 L/min, ZEEP) to 0.25 kg.m/L (Drager EV-A, 6-mm ETT, 100 L/min, ZEEP), the latter representing 490% of the work of normal breathing. This additional work imposed by the ETT varied considerably among devices. Spontaneous breathing through modern ventilators, circuits and ETT imposes a burden of increased work, most of which is associated with the presence of the ETT and connector. Whether this burden represents an impediment to the weaning patient, or has training value for the ultimate resumption of unassisted spontaneous ventilation, remains to be determined.

  1. Nonlinear dynamics and health monitoring of 6-DOF breathing cracked Jeffcott rotor

    NASA Astrophysics Data System (ADS)

    Zhao, Jie; DeSmidt, Hans; Yao, Wei

    2015-04-01

    Jeffcott rotor is employed to study the nonlinear vibration characteristics of breathing cracked rotor system and explore the possibility of further damage identification. This paper is an extension work of prior study based on 4 degree-of-freedom Jeffcott rotor system. With consideration of disk tilting and gyroscopic effect, 6-dof EOM is derived and the crack model is established using SERR (strain energy release rate) in facture mechanics. Same as the prior work, the damaged stiffness matrix is updated by computing the instant crack closure line through Zero Stress Intensity Factor method. The breathing crack area is taken as a variable to analyze the breathing behavior in terms of eccentricity phase and shaft speed. Furthermore, the coupled vibration among lateral, torsional and longitudinal d.o.f is studied under torsional/axial excitation. The final part demonstrates the possibility of using vibration signal of damaged system for the crack diagnosis and health monitoring.

  2. Sudarshan kriya yoga: Breathing for health.

    PubMed

    Zope, Sameer A; Zope, Rakesh A

    2013-01-01

    Breathing techniques are regularly recommended for relaxation, stress management, control of psychophysiological states, and to improve organ function. Yogic breathing, defined as a manipulation of breath movement, has been shown to positively affect immune function, autonomic nervous system imbalances, and psychological or stress-related disorders. The aim of this study was to assess and provide a comprehensive review of the physiological mechanisms, the mind-body connection, and the benefits of Sudarshan Kriya Yoga (SKY) in a wide range of clinical conditions. Various online databases searched were Medline, Psychinfo, EMBASE, and Google Scholar. All the results were carefully screened and articles on SKY were selected. The references from these articles were checked to find any other potentially relevant articles. SKY, a unique yogic breathing practice, involves several types of cyclical breathing patterns, ranging from slow and calming to rapid and stimulating. There is mounting evidence to suggest that SKY can be a beneficial, low-risk, low-cost adjunct to the treatment of stress, anxiety, post-traumatic stress disorder, depression, stress-related medical illnesses, substance abuse, and rehabilitation of criminal offenders. PMID:23440614

  3. Breath suspension during the transcendental meditation technique.

    PubMed

    Farrow, J T; Hebert, J R

    1982-05-01

    We observed, over four independent experiments, 565 criterion-meeting episodes of breath suspension in 40 subjects practicing the Transcendental Mediation technique (TM), a simple mental technique involving no breath control procedures. The frequency and length of these breath suspension episodes were substantially and significantly greater for TM subjects than for control subjects relaxing with eyes closed. Voluntary control of respiration was most probably eliminated as an explanation of ths phenomenon by the experimental design and by the use of a variety of nonintrusive respiration transducers, including a two-channel magnetometer, an indirect but accurate means of monitoring respiration. Many TM subjects report experience of a completely quiescent mental state characterized by maintained awareness in the absence of thought. Eleven TM subjects were instructed to press an event mark button after each episode of this pure consciousness experience. The temporal distribution of button presses was significantly related (p less than 10(-10) to the distribution of breath suspension episodes, indicating that breath suspension is a physiological correlate of some, but not all, episodes of the pure consciousness experience. In an extensive study of a single advanced mediator, pure consciousness experiences were also associated with reduced heart rate; high basal skin resistance; stable phasic skin resistance; markedly reduced mean respiration rate, mean minute ventilation and mean metabolic rate; and statistically consistent changes in EEG power and EEG coherence (an indicator of long-range spatial order in the nervous system).

  4. Breath tests in diagnosis of pulmonary tuberculosis.

    PubMed

    Cheepsattayakorn, Attapon; Cheepsattayakorn, Ruangrong

    2014-01-01

    Since the time of Hippocrates, physicians have known that the odour of human breath can provide clues to diagnosis. In the past, hydrogen peroxide which is a marker of inflammatory diseases and oxidative stress was the most studied substance in the exhaled breath which was detectable in the liquid that obtained by condensing or cooling. The advantages of breath analysis are that it is convenient, non-invasive, and could be performed with children as well as mechanically ventilated patients. Today, exhaled nitric oxide has been studied extensively, especially in relation to asthma. More than a thousand different volatile organic compounds have been observed in low concentrations in normal human breath. Alkanes and methylalkanes have been increasingly used by physicians as a novel method to diagnose many diseases without discomforts of invasive procedures. Although the limitations of measurement of exhaled nitric oxide in direct diagnosis of infectious pulmonary TB, it may have potential development as a cost-effective replacement of chest radiological examination in screening algorithms. None of the individual exhaled volatile organic compound alone is specific for disease. Exhaled breath analysis techniques may be available to diagnose and monitor the diseases in home setting when their sensitivity and specificity are expected to improve in the future. Here, we also discussed some patents related to the topic. PMID:25185981

  5. Pulse Ejection Presentation System Synchronized with Breathing

    NASA Astrophysics Data System (ADS)

    Kadowaki, Ami; Sato, Junta; Ohtsu, Kaori; Bannai, Yuichi; Okada, Kenichi

    Trials on transmission of olfactory information together with audio/visual information are currently being conducted in the field of multimedia. However, continuous emission of scents in high concentration creates problems of human adaptation and remnant odors in air. To overcome such problems we developed an olfactory display in conjunction with Canon Inc. This display has high emission control in the ink-jet so that it can provide stable pulse emission of scents. Humans catch a scent when they breathe in and inhale smell molecules in air. Therefore, it is important that the timing of scent presentation is synchronized with human breathing. We also developed a breath sensor which detects human inspiration. In this study, we combined the olfactory display with the breath sensor to make a pulse ejection presentation system synchronized the breath. The experimental evaluation showed that the system had more than 90 percent of detection rate. Another evaluation was held at KEIO TECHNO-MALL 2007. From questionnaire results of the participants, we found that the system made the user feel continuous sense of smell avoiding adaptation. It is expected that our system enables olfactory information to be synchronized with audio/visual information in arbitrary duration at any time.

  6. Sudarshan kriya yoga: Breathing for health

    PubMed Central

    Zope, Sameer A.; Zope, Rakesh A

    2013-01-01

    Breathing techniques are regularly recommended for relaxation, stress management, control of psychophysiological states, and to improve organ function. Yogic breathing, defined as a manipulation of breath movement, has been shown to positively affect immune function, autonomic nervous system imbalances, and psychological or stress-related disorders. The aim of this study was to assess and provide a comprehensive review of the physiological mechanisms, the mind–body connection, and the benefits of Sudarshan Kriya Yoga (SKY) in a wide range of clinical conditions. Various online databases searched were Medline, Psychinfo, EMBASE, and Google Scholar. All the results were carefully screened and articles on SKY were selected. The references from these articles were checked to find any other potentially relevant articles. SKY, a unique yogic breathing practice, involves several types of cyclical breathing patterns, ranging from slow and calming to rapid and stimulating. There is mounting evidence to suggest that SKY can be a beneficial, low-risk, low-cost adjunct to the treatment of stress, anxiety, post-traumatic stress disorder, depression, stress-related medical illnesses, substance abuse, and rehabilitation of criminal offenders. PMID:23440614

  7. [Psoriasis and cardiovascular disease].

    PubMed

    Torres, Tiago; Sales, Rita; Vasconcelos, Carlos; Selores, Manuela

    2013-01-01

    Psoriasis is a common, chronic and systemic inflammatory disease associated with several comorbidities, such as obesity, hypertension, diabetes, dyslipidaemia and metabolic syndrome, but also with an increased risk of cardiovascular disease, like myocardial infarction or stroke. The chronic inflammatory nature of psoriasis has been suggested to be a contributing and potentially independent risk factor for the development of cardiovascular comorbidities and precocious atherosclerosis. Aiming at alerting clinicians to the need of screening and monitoring cardiovascular diseases and its risk factors in psoriatic patients, this review will focus on the range of cardiometabolic comorbidities and increased risk of cardiovascular disease associated with psoriasis.

  8. A comprehensive assessment of cardiovascular autonomic control using photoplethysmograms recorded from the earlobe and fingers.

    PubMed

    Kiselev, A R; Mironov, S A; Karavaev, A S; Kulminskiy, D D; Skazkina, V V; Borovkova, E I; Shvartz, V A; Ponomarenko, V I; Prokhorov, M D

    2016-04-01

    We compare the spectral indices of photoplethysmogram variability (PPGV) estimated using photoplethysmograms recorded from the earlobe and the middle fingers of the right and left hand and analyze their correlation with similar indices of heart rate variability (HRV) in 30 healthy subjects (26 men) aged 27 (25, 29) years (median with inter-quartile ranges) at rest and under the head-up tilt test. The following spectral indices of PPGV and HRV were compared: mean heart rate (HR), total spectral power (TP), high-frequency (HF) and low-frequency (LF) ranges of TP in percents (HF% and LF%), LF/HF ratio, and spectral coherence. We assess also the index S of synchronization between the LF oscillations in HRV and PPGV. The constancy of blood pressure (BP) and moderate increase of HR under the tilt test indicate the presence of fast processes of cardiovascular adaptation with the increase of the sympathetic activity in studied healthy subjects. The impact of respiration on the PPGV spectrum (accessed by HF%) is less than on the HRV spectrum. It is shown that the proportion of sympathetic vascular activity (accessed by LF%) is constant in the PPGV of three analyzed PPGs during the tilt test. The PPGV for the ear PPG was less vulnerable to breathing influence accessed by HF% (independently from body position) than for PPGs from fingers. We reveal the increase of index S under the tilt test indicating the activation of interaction between the heart and distal vessels. The PPGV spectra for finger PPGs from different hands are highly coherent, but differ substantially from the PPGV spectrum for the ear PPG. We conclude that joint analysis of frequency components of PPGV (for the earlobe and finger PPGs of both hands) and HRV and assessment of their synchronization provide additional information about cardiovascular autonomic control. PMID:27027461

  9. Variability for Categorical Variables

    ERIC Educational Resources Information Center

    Kader, Gary D.; Perry, Mike

    2007-01-01

    Introductory statistics textbooks rarely discuss the concept of variability for a categorical variable and thus, in this case, do not provide a measure of variability. The impression is thus given that there is no measurement of variability for a categorical variable. A measure of variability depends on the concept of variability. Research has…

  10. Acute exposure to acid fog: influence of breathing pattern on effective dose.

    PubMed

    Bowes, S M; Francis, M; Laube, B L; Frank, R

    1995-02-01

    Concern about the possible adverse health effects of acid fog has been fed by two observations: air pollution disasters earlier in this century were typically associated with fog, and current samples of fog water can be strongly acid. To study the acute effects of acid fog on the lung, the authors generated a monodisperse 10 microM MMAD aerosol of H2SO4 with a pH of 2.0 and a nominal concentration of 500 micrograms/m3. They exposed seven healthy young men on alternate days to acid or control equiosmolar NaCl aerosol during 40 min of resting ventilation and 20 min of exercise; the latter was sufficiently intense to induce oronasal breathing. Exposure was by means of a head dome, a head-only exposure device that permitted continuous measurement (unfettered breathing) of Vr, f, VE, and the onset and persistence of oronasal breathing. In this article the authors compare the relative importance of parameters contributing to the between-subject variability in estimated hydrogen ion dose to the lower airways (H+LAW), based on analysis of variance. Physiologic parameters accounted for 70% of the variability, of which 34% was due to differences in duration of oronasal breathing (tON) and 36% to differences in ventilation rate during oronasal breathing (VE(ON)); inhaled hydrogen ion concentration [H+], the environmental parameter, contributed only 30%. Minute ventilation at the time of transition from nasal to oronasal breathing varied significantly among subjects even if normalized to FVC, an index of lung size.

  11. Technologies for Clinical Diagnosis Using Expired Human Breath Analysis.

    PubMed

    Mathew, Thalakkotur Lazar; Pownraj, Prabhahari; Abdulla, Sukhananazerin; Pullithadathil, Biji

    2015-01-01

    This review elucidates the technologies in the field of exhaled breath analysis. Exhaled breath gas analysis offers an inexpensive, noninvasive and rapid method for detecting a large number of compounds under various conditions for health and disease states. There are various techniques to analyze some exhaled breath gases, including spectrometry, gas chromatography and spectroscopy. This review places emphasis on some of the critical biomarkers present in exhaled human breath, and its related effects. Additionally, various medical monitoring techniques used for breath analysis have been discussed. It also includes the current scenario of breath analysis with nanotechnology-oriented techniques. PMID:26854142

  12. Technologies for Clinical Diagnosis Using Expired Human Breath Analysis

    PubMed Central

    Mathew, Thalakkotur Lazar; Pownraj, Prabhahari; Abdulla, Sukhananazerin; Pullithadathil, Biji

    2015-01-01

    This review elucidates the technologies in the field of exhaled breath analysis. Exhaled breath gas analysis offers an inexpensive, noninvasive and rapid method for detecting a large number of compounds under various conditions for health and disease states. There are various techniques to analyze some exhaled breath gases, including spectrometry, gas chromatography and spectroscopy. This review places emphasis on some of the critical biomarkers present in exhaled human breath, and its related effects. Additionally, various medical monitoring techniques used for breath analysis have been discussed. It also includes the current scenario of breath analysis with nanotechnology-oriented techniques. PMID:26854142

  13. Acute effects of caffeine on heart rate variability in habitual caffeine consumers.

    PubMed

    Rauh, Robert; Burkert, Michaela; Siepmann, Martin; Mueck-Weymann, Michael

    2006-05-01

    During the last years, heart rate variability (HRV) has become a promising risk factor for cardiovascular events. However, the effect of caffeine on HRV in habitual caffeine consumers has barely been investigated. Therefore, we treated 30 male habitual caffeine users in a randomized double-blinded crossover study design with either placebo, 100 or 200 mg caffeine orally and determined parameters of HRV under resting conditions and metronomic breathing. As result, we could not detect significant differences in HRV parameters up to 90 min after drug ingestion. We conclude that modest amounts of caffeine do not reveal negative nor positive effects on HRV within the first 90 min after drug ingestion in young and healthy habitual caffeine consumers. However, further research is necessary to determine the effects of caffeine on HRV in habitual caffeine users, healthy as well as suffering from diabetes, hypertension and postmyocardial infarction.

  14. Sleep and Breathing at High Altitude.

    PubMed

    Wickramasinghe, Himanshu; Anholm, James D.

    1999-01-01

    Sleep at high altitude is characterized by poor subjective quality, increased awakenings, frequent brief arousals, marked nocturnal hypoxemia, and periodic breathing. A change in sleep architecture with an increase in light sleep and decreasing slow-wave and REM sleep have been demonstrated. Periodic breathing with central apnea is almost universally seen amongst sojourners to high altitude, although it is far less common in long-standing high altitude dwellers. Hypobaric hypoxia in concert with periodic breathing appears to be the principal cause of sleep disruption at altitude. Increased sleep fragmentation accounts for the poor sleep quality and may account for some of the worsened daytime performance at high altitude. Hypoxic sleep disruption contributes to the symptoms of acute mountain sickness. Hypoxemia at high altitude is most severe during sleep. Acetazolamide improves sleep, AMS symptoms, and hypoxemia at high altitude. Low doses of a short acting benzodiazepine (temazepam) may also be useful in improving sleep in high altitude. PMID:11898114

  15. Effect of dietary turmeric on breath hydrogen.

    PubMed

    Shimouchi, Akito; Nose, Kazutoshi; Takaoka, Motoko; Hayashi, Hiroko; Kondo, Takaharu

    2009-08-01

    Turmeric is widely used in Indian cuisine. The main constituents of turmeric are curcumin and its analogues, which are well-known antioxidant compounds. In the present study, we hypothesized that turmeric in curry might increase bowel motility and activate hydrogen-producing bacterial flora in the colon, thereby increasing the concentration of breath hydrogen. Eight healthy subjects fasted for 12 h and ingested curry and rice with or without turmeric (turmeric knockout curry). Breath-hydrogen concentrations were analyzed every 15 min for 6 h by gas chromatography with a semiconductor detector. Curry with turmeric significantly increased the area under the curve of breath hydrogen and shortened small-bowel transit time, compared with curry not containing turmeric. These results suggested that dietary turmeric activated bowel motility and carbohydrate colonic fermentation. PMID:19034660

  16. A computational model of cardiovascular physiology and heart sound generation.

    PubMed

    Watrous, Raymond L

    2009-01-01

    A computational model of the cardiovascular system is described which provides a framework for implementing and testing quantitative physiological models of heart sound generation. The lumped-parameter cardiovascular model can be solved for the hemodynamic variables on which the heart sound generation process is built. Parameters of the cardiovascular model can be adjusted to represent various normal and pathological conditions, and the acoustic consequences of those adjustments can be explored. The combined model of the physiology of cardiovascular circulation and heart sound generation has promise for application in teaching, training and algorithm development in computer-aided auscultation of the heart.

  17. Mechanism of blood pressure and R-R variability: insights from ganglion blockade in humans

    NASA Technical Reports Server (NTRS)

    Zhang, Rong; Iwasaki, Kenichi; Zuckerman, Julie H.; Behbehani, Khosrow; Crandall, Craig G.; Levine, Benjamin D.; Blomqvist, C. G. (Principal Investigator)

    2002-01-01

    Spontaneous blood pressure (BP) and R-R variability are used frequently as 'windows' into cardiovascular control mechanisms. However, the origin of these rhythmic fluctuations is not completely understood. In this study, with ganglion blockade, we evaluated the role of autonomic neural activity versus other 'non-neural' factors in the origin of BP and R-R variability in humans. Beat-to-beat BP, R-R interval and respiratory excursions were recorded in ten healthy subjects (aged 30 +/- 6 years) before and after ganglion blockade with trimethaphan. The spectral power of these variables was calculated in the very low (0.0078-0.05 Hz), low (0.05-0.15 Hz) and high (0.15-0.35 Hz) frequency ranges. The relationship between systolic BP and R-R variability was examined by cross-spectral analysis. After blockade, R-R variability was virtually abolished at all frequencies; however, respiration and high frequency BP variability remained unchanged. Very low and low frequency BP variability was reduced substantially by 84 and 69 %, respectively, but still persisted. Transfer function gain between systolic BP and R-R interval variability decreased by 92 and 88 % at low and high frequencies, respectively, while the phase changed from negative to positive values at the high frequencies. These data suggest that under supine resting conditions with spontaneous breathing: (1) R-R variability at all measured frequencies is predominantly controlled by autonomic neural activity; (2) BP variability at high frequencies (> 0.15 Hz) is mediated largely, if not exclusively, by mechanical effects of respiration on intrathoracic pressure and/or cardiac filling; (3) BP variability at very low and low frequencies (< 0.15 Hz) is probably mediated by both sympathetic nerve activity and intrinsic vasomotor rhythmicity; and (4) the dynamic relationship between BP and R-R variability as quantified by transfer function analysis is determined predominantly by autonomic neural activity rather than other

  18. Electrospray ionization of volatiles in breath

    NASA Astrophysics Data System (ADS)

    Martínez-Lozano, P.; de La Mora, J. Fernández

    2007-08-01

    Recent work by Zenobi and colleagues [H. Chen, A. Wortmann, W. Zhang, R. Zenobi, Angew. Chem. Int. Ed. 46 (2007) 580] reports that human breath charged by contact with an electrospray (ES) cloud yields many mass peaks of species such as urea, glucose, and other ions, some with molecular weights above 1000 Da. All these species are presumed to be involatile, and to originate from breath aerosols by so-called extractive electrospray ionization EESI [H. Chen, A. Venter, R.G. Cooks, Chem. Commun. (2006) 2042]. However, prior work by Fenn and colleagues [C.M. Whitehouse, F. Levin, C.K. Meng, J.B. Fenn, Proceedings of the 34th ASMS Conference on Mass Spectrometry and Allied Topics, Denver, 1986 p. 507; S. Fuerstenau, P. Kiselev, J.B. Fenn, Proceedings of the 47th ASMS Conference on Mass Spectrometry, 1999, Dallas, TX, 1999] and by Hill and colleagues [C. Wu, W.F. Siems, H.H. Hill Jr., Anal. Chem. 72 (2000) 396] have reported the ability of electrospray drops to ionize a variety of low vapor pressure substances directly from the gas phase, without an apparent need for the vapor to be brought into the charging ES in aerosol form. The Ph.D. Thesis of Martínez-Lozano [P. Martínez-Lozano Sinués, Ph.D. Thesis, Department of Thermal and Fluid Engineering, University Carlos III of Madrid; April 5, 2006 (in Spanish); http://hdl.handle.net/10016/655] had also previously argued that the numerous human breath species observed via a similar ES ionization approach were in fact ionized directly from the vapor. Here, we observe that passage of the breath stream through a submicron filter does not eliminate the majority of the breath vapors seen in the absence of the filter. We conclude that direct vapor charging is the leading mechanism in breath ionization by electrospray drops, though aerosol ionization may also play a role.

  19. User's instructions for the cardiovascular Walters model

    NASA Technical Reports Server (NTRS)

    Croston, R. C.

    1973-01-01

    The model is a combined, steady-state cardiovascular and thermal model. It was originally developed for interactive use, but was converted to batch mode simulation for the Sigma 3 computer. The model has the purpose to compute steady-state circulatory and thermal variables in response to exercise work loads and environmental factors. During a computer simulation run, several selected variables are printed at each time step. End conditions are also printed at the completion of the run.

  20. Subjective Social Status and Cardiovascular Reactivity: An Experimental Examination

    PubMed Central

    Pieritz, Karoline; Süssenbach, Philipp; Rief, Winfried; Euteneuer, Frank

    2016-01-01

    The present experiment examined the causal influence of subjective social status (SSS) on variables related to cardiovascular health [i.e., blood pressure, heart rate variability (HRV)]. Participants were randomly assigned to one of two conditions involving a social comparison that either induced a temporary shift toward high SSS or toward low SSS. Cardiovascular variables were measured before (baseline), throughout, and after the manipulation (recovery). Participants in the low SSS condition had a significantly lower HRV during experimental manipulation than at baseline (p = 0.001). They also showed a significantly stronger HRV reactivity compared to participants in the high SSS condition (p = 0.027). Our results suggest that already temporary shifts of one's SSS have measureable effects on cardiovascular variables. They support the notion that social status plays a causal role in the development of cardiovascular disease. PMID:27486426

  1. Sleep-Disordered Breathing and Cardiac Arrhythmias.

    PubMed

    Bitter, Thomas; Fox, Henrik; Gaddam, SaiPrassad; Horstkotte, Dieter; Oldenburg, Olaf

    2015-07-01

    Over the past few years sleep-disordered breathing has been identified as an important factor in arrhythmogenesis and a potential target of therapy to prevent cardiac arrhythmias in selected patients. In this review we highlight the role of obstructive sleep apnea and Cheyne-Stokes respiration in the pathophysiology of arrhythmias, address their clinical effect in supraventricular and ventricular tachyarrhythmias, and in conduction disturbances, and address the role of current treatment options for sleep-disordered breathing in the primary and secondary prevention of arrhythmic events.

  2. Medication effects on sleep and breathing.

    PubMed

    Seda, Gilbert; Tsai, Sheila; Lee-Chiong, Teofilo

    2014-09-01

    Sleep respiration is regulated by circadian, endocrine, mechanical and chemical factors, and characterized by diminished ventilatory drive and changes in Pao2 and Paco2 thresholds. Hypoxemia and hypercapnia are more pronounced during rapid eye movement. Breathing is influenced by sleep stage and airway muscle tone. Patient factors include medical comorbidities and body habitus. Medications partially improve obstructive sleep apnea and stabilize periodic breathing at altitude. Potential adverse consequences of medications include precipitation or worsening of disorders. Risk factors for adverse medication effects include aging, medical disorders, and use of multiple medications that affect respiration.

  3. Breathing air trailer acceptance test procedure

    SciTech Connect

    Kostelnik, A.J.

    1994-09-14

    This Acceptance Test Procedure (ATP) will document compliance with the requirements of WHC-S-0251 Rev. 0 and ECNs 613530 and 606113. The equipment being tested is a Breathing Air Supply Trailer purchased as a Design and Fabrication procurement activity for use in the core sampling program. The ATP was written by the Seller and will be performed by the Seller with representatives of the Westinghouse Hanford Company witnessing the test at the Seller`s location. This test procedure is to verify that the American Bristol Industries, Inc., Model 5014-0001 low pressure Mobile Breathing Air Trailer, meets or exceeds the requirements of the Westinghouse Hanford specification.

  4. Cardiovascular disease among firefighters.

    PubMed

    Melius, J M

    1995-01-01

    The author reviews the literature of the past 20 years on heart disease among firefighters, covering the specific aspects of firefighting that may be related to potential cardiovascular disease. The author then outlines steps that can be taken to reduce the risks of developing cardiovascular disease.

  5. Breath-based meditation: A mechanism to restore the physiological and cognitive reserves for optimal human performance.

    PubMed

    Carter, Kirtigandha Salwe; Carter, Robert

    2016-04-16

    Stress can be associated with many physiological changes resulting in significant decrements in human performance. Due to growing interests in alternative and complementary medicine by Westerners, many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles. These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder. However, the potential of yogic breathing on optimizing human performance and overall well-being is not well known. Breathing techniques such as alternate nostril, Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness. Furthermore, yogic breathing is physiologically stimulating and can be described as a natural "technological" solution to optimize human performance which can be categorized into: (1) cognitive function (i.e., mind, vigilance); and (2) physical performance (i.e., cardiorespiratory, metabolism, exercise, whole body). Based on previous studies, we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function. This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state (i.e., hypertension, depression, dementia) or acute state (i.e., massive hemorrhage, panic attic) of medical conditions. However, additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation (i.e., breath-based, mantra, mindfulness) on human performance. These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation. While it has been suggested that breath-based meditation is easier for

  6. Breath-based meditation: A mechanism to restore the physiological and cognitive reserves for optimal human performance

    PubMed Central

    Carter, Kirtigandha Salwe; Carter III, Robert

    2016-01-01

    Stress can be associated with many physiological changes resulting in significant decrements in human performance. Due to growing interests in alternative and complementary medicine by Westerners, many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles. These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder. However, the potential of yogic breathing on optimizing human performance and overall well-being is not well known. Breathing techniques such as alternate nostril, Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness. Furthermore, yogic breathing is physiologically stimulating and can be described as a natural “technological” solution to optimize human performance which can be categorized into: (1) cognitive function (i.e., mind, vigilance); and (2) physical performance (i.e., cardiorespiratory, metabolism, exercise, whole body). Based on previous studies, we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function. This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state (i.e., hypertension, depression, dementia) or acute state (i.e., massive hemorrhage, panic attic) of medical conditions. However, additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation (i.e., breath-based, mantra, mindfulness) on human performance. These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation. While it has been suggested that breath-based meditation is easier

  7. Breath-based meditation: A mechanism to restore the physiological and cognitive reserves for optimal human performance.

    PubMed

    Carter, Kirtigandha Salwe; Carter, Robert

    2016-04-16

    Stress can be associated with many physiological changes resulting in significant decrements in human performance. Due to growing interests in alternative and complementary medicine by Westerners, many of the traditions and holistic yogic breathing practices today are being utilized as a measure for healthier lifestyles. These state-of-the-art practices can have a significant impact on common mental health conditions such as depression and generalized anxiety disorder. However, the potential of yogic breathing on optimizing human performance and overall well-being is not well known. Breathing techniques such as alternate nostril, Sudarshan Kriya and bhastrika utilizes rhythmic breathing to guide practitioners into a deep meditative state of relaxation and promote self-awareness. Furthermore, yogic breathing is physiologically stimulating and can be described as a natural "technological" solution to optimize human performance which can be categorized into: (1) cognitive function (i.e., mind, vigilance); and (2) physical performance (i.e., cardiorespiratory, metabolism, exercise, whole body). Based on previous studies, we postulate that daily practice of breathing meditation techniques play a significant role in preserving the compensatory mechanisms available to sustain physiological function. This preservation of physiological function may help to offset the time associated with reaching a threshold for clinical expression of chronic state (i.e., hypertension, depression, dementia) or acute state (i.e., massive hemorrhage, panic attic) of medical conditions. However, additional rigorous biomedical research is needed to evaluate the physiological mechanisms of various forms of meditation (i.e., breath-based, mantra, mindfulness) on human performance. These efforts will help to define how compensatory reserve mechanisms of cardiovascular and immune systems are modulated by breath-based meditation. While it has been suggested that breath-based meditation is easier for

  8. The mathematical analysis of breath alcohol profiles generated during breath exhalation.

    PubMed

    Gullberg, R G

    1990-01-01

    The mathematical analysis of time domain data provides a useful tool for evaluating biological and instrumental systems. Breath alcohol profile measurements generated during exhalation constitute biological signals that can be subjected to a variety of mathematical treatments. The present paper discusses the application of a variety of mathematical procedures to breath alcohol profiles. These mathematical procedures include model approximation, data smoothing, integration, differentiation, and fourier transformation. The different mathematical procedures provide insight into the physiology of breath alcohol measurement and suggest forensic as well as instrumental applications.

  9. Flute ``breath support'' perception and its acoustical correlates

    NASA Astrophysics Data System (ADS)

    Cossette, Isabelle A.; Sabourin, Patrick

    2001-05-01

    Music educators and performers commonly refer to ``breath support'' in flute playing, yet the term ``support'' is neither well-defined nor consistently used. Different breathing strategies used by professional flautists who were instructed to play with and without support were previously identified by the authors. In the current study, 14 musical excerpts with and without support were recorded by five professional flautists. Eleven professional flautists listened to the recordings in a random order and ranked (1 to 6) how much of the following sound qualities they judged to be in each example: support, intonation, control and musical expressiveness. Answers to the test showed that musical expressiveness was associated more closely with the supported excerpts than the answers about support itself. The ratings for each sound quality were highly intercorrelated. Acoustical parameters were analyzed (frequency and centroid variation within each note) and compared with the results of the perception test in order to better understand how the acoustical and psychological variables were related. The acoustical analysis of the central part of the notes did not show evident correlation with the answers of the perception test. [Work funded by the Social Sciences and Humanities Research Council of Canada.

  10. Microgravity reduces sleep-disordered breathing in humans

    NASA Technical Reports Server (NTRS)

    Elliott, A. R.; Shea, S. A.; Dijk, D. J.; Wyatt, J. K.; Riel, E.; Neri, D. F.; Czeisler, C. A.; West, J. B.; Prisk, G. K.

    2001-01-01

    To understand the factors that alter sleep quality in space, we studied the effect of spaceflight on sleep-disordered breathing. We analyzed 77 8-h, full polysomnographic recordings (PSGs) from five healthy subjects before spaceflight, on four occasions per subject during either a 16- or 9-d space shuttle mission and shortly after return to earth. Microgravity was associated with a 55% reduction in the apnea-hypopnea index (AHI), which decreased from a preflight value of 8.3 +/- 1.6 to 3.4 +/- 0.8 events/h inflight. This reduction in AHI was accompanied by a virtual elimination of snoring, which fell from 16.5 +/- 3.0% of total sleep time preflight to 0.7 +/- 0.5% inflight. Electroencephalogram (EEG) arousals also decreased in microgravity (by 19%), and this decrease was almost entirely a consequence of the reduction in respiratory-related arousals, which fell from 5.5 +/- 1.2 arousals/h preflight to 1.8 +/- 0.6 inflight. Postflight there was a return to near or slightly above preflight levels in these variables. We conclude that sleep quality during spaceflight is not degraded by sleep-disordered breathing. This is the first direct demonstration that gravity plays a dominant role in the generation of apneas, hypopneas, and snoring in healthy subjects.

  11. Elimination kinetics of volatile organics in humans using breath measurements

    SciTech Connect

    Pellizzari, E.D.; Wallace, L.A.; Gordon, S.M. )

    1992-07-01

    During the past decade significant strides have been made toward understanding the sources and factors which lead to volatile organic chemical (VOC) exposure in the general population. Less is known, however, about the impact of low-level environmental exposure on human health. Investigations are underway in a number of laboratories in an effort to determine the uptake, distribution, metabolism, and elimination kinetics for VOCs in humans. We examined the elimination kinetics for the third phase for ten VOCs--1,1,-trichloroethane, trichloroethylene, tetrachloroethylene, benzene, toluene, m,p-xylenes, o-xylene, ethylbenzene, p-dichlorobenzene, and limonene--in human subjects. Subjects were exposed to a variety of common consumer products and breath samples were collected post-exposure while the subjects spent up to 10 hr in a clean air environment. VOCs from breath samples were collected into canisters or onto Tenax GC cartridges and analyzed by gas chromatography-mass spectrometry. Exponential modeling of the decay data was performed to obtain kinetic parameters. The half-lives for trichloroethylene and 1,1,1-trichloroethane were approximately 5 to 8 hr for the four subjects. In general, the magnitude and range of variability was larger for toluene, limonene, and p-dichlorobenzene than for the other VOCs; the elimination rate spanning a few hours to a day or two. Thus, VOCs exhibit relatively short residence times in the body relative to other halo-carbons, such as polychlorinated biphenyls and dioxins.

  12. Facial and dental alterations according to the breathing pattern

    PubMed Central

    RETAMOSO, Luciana Borges; KNOP, Luégya Amorin Henriques; GUARIZA FILHO, Odilon; TANAKA, Orlando Motohiro

    2011-01-01

    There is controversy in the literature about possible interaction of the respiratory mode with the facial and dental structures. Objectives The aim of this study was to perform a longitudinal assessment of the changes in facial and dental structures in Angle’s Class II, division 1 malocclusion individuals, divided according to the respiratory pattern (predominantly nasal or mouth), at two distinct moments of craniofacial development. Material and Methods Pogonium and nose measurements were made on the lateral cephalometric tracings (LS’-Pog’, LS’-B’, B’-Pog’, Pog’-PogTeg’, Line NB, Pog-NB, N'-Prn, Prn-NPog, N-Prn-Sn, Prn-Sn-LS). Dental measurements were made on the plaster models (distances between the tips of the canine cusps and the tips of mesial cusps of the first molars) of 40 individuals aged 10 to 14 years (moment 1) and 13 to 16 years (moment 2), 23 being nose breathers (NB) and 17 being predominantly mouth breathers (MB). Results The Student’s-t test and two-way ANOVA with repeated measures were applied to indicate differences between the mean values of these variables according to the moments and/or respiratory mode. Conclusions There were alterations in the facial measurements, without interference of the breathing pattern. However, the breathing pattern influenced dental alterations. PMID:21552720

  13. Asthma: vocal cord dysfunction (VCD) and other dysfunctional breathing disorders.

    PubMed

    Balkissoon, Ron; Kenn, Klaus

    2012-12-01

    Vocal cord dysfunction (VCD) and dysfunctional breathing (DB) disorders may mimic or coexist with asthma, leading to overtreatment with corticosteroids with consequent morbidity. Iatrogenic complications can be averted by early and correct diagnosis. VCD, also termed paradoxical vocal fold motion disorder (PVFMD), is characterized by intermittent paradoxical adduction of the vocal cords, mainly during inspiration, leading to airflow obstruction and dyspnea. Patients with VCD may have repetitive emergency room visits due to acute dyspnea (mimicking exacerbations of asthma). In the seminal descriptions of VCD, young women (often with psychiatric issues) predominated; however, other groups at increased risk for developing VCD include elite athletes, military recruits, and individuals exposed to irritants (inhaled or aspirated). Chronic postnasal drip, laryngopharyngeal reflux (LPR), and gastroesophageal reflux (GER) may lead to laryngeal hyperresponsiveness. The diagnosis of VCD may be difficult because physical exam and spirometry may be normal between episodes. During symptomatic episodes, spirometry typically reveals variable extrathoracic airway obstruction (truncated inspiratory flow volume loop). The gold standard for identifying VCD is flexible fiberoptic rhinolaryngoscopy. Management of VCD includes identification and treatment of underlying disorders (eg, chronic postnasal drip, LPR, GER, anxiety, depression) and a multidisciplinary approach (including highly trained speech therapists). Speech therapy and biofeedback play a critical role in teaching techniques to override various dysfunctional breathing habits. When postnasal drip, LPR, or GER coexist, these disorders should be aggressively treated. With successful therapy, corticosteroids can often be discontinued. During severe, acute episodes of VCD, therapeutic strategies include heliox (80% helium/20% oxygen), topical lidocaine, anxiolytics, and superior laryngeal blocks with Clostridium botulinum toxin

  14. Use of complementary therapies in patients with cardiovascular disease.

    PubMed

    Yeh, Gloria Y; Davis, Roger B; Phillips, Russell S

    2006-09-01

    Previous studies have suggested that patients with chronic medical conditions use complementary and alternative medicine (CAM) at a higher rate than the general population. Despite recent interest in CAM for cardiovascular disease, few data are available regarding patterns of use in patients with cardiovascular disease in the United States. This study used the 2002 National Health Interview Survey and analyzed data on CAM use in 10,572 respondents with cardiovascular disease. Among those with cardiovascular disease, 36% had used CAM (excluding prayer) in the previous 12 months. The most commonly used therapies were herbal products (18%) and mind-body therapies (17%). Among herbs, echinacea, garlic, ginseng, ginkgo biloba, and glucosamine with or without chondroitin were most commonly used. Among mind-body therapies, deep-breathing exercises and meditation were most commonly used. Overall, CAM was used most frequently for musculoskeletal complaints (24% of respondents who used mind-body therapies, 22% who used herbs, 45% who used any CAM). Mind-body therapies were also used for anxiety or depression (23%) and stress or emotional health and wellness (16%). Herbs were commonly used for head and chest colds (22%). Fewer respondents (10%) used CAM specifically for their cardiovascular conditions (5% for hypertension, 2% for coronary disease, 3% for vascular insufficiency, < 1% for heart failure or stroke). Most, however, who used CAM for their cardiovascular condition perceived the therapies to be helpful (80% for herbs, 94% for mind-body therapies). CAM use was more common in younger respondents, women, Asians, and those with more education and greater incomes. In conclusion, CAM use, particularly herbs and mind-body therapies, is common in the United States in patients with cardiovascular disease and mirrors use in the general population. CAM use specifically to treat cardiovascular conditions, however, is less common.

  15. Coughing Wheezing Shortness of Breath Tightness in Chest

    MedlinePlus

    ... Current Issue Past Issues Coughing Wheezing Shortness of Breath Tightness in Chest Past Issues / Fall 2006 Table ... you cough a lot, wheeze, are short of breath or feel tightness in your chest, you might ...

  16. Meeting Reports for 2013: Recent Advances in Breath Biomarker Research

    EPA Science Inventory

    This article reports the efforts of the breath research community affiliated with the International Association of Breath Research (IABR) in disseminating research results in high profile technical meetings in the United States (US). Specifically, we describe presentations at a ...

  17. ALVEOLAR BREATH SAMPLING AND ANALYSIS IN HUMAN EXPOSURE ASSESSMENT STUDIES

    EPA Science Inventory

    Alveolar breath sampling and analysis can be extremely useful in exposure assessment studies involving volatile organic compounds (VOCs). Over recent years scientists from the EPA's National Exposure Research Laboratory have developed and refined an alveolar breath collection ...

  18. Pitfalls in the evaluation of shortness of breath.

    PubMed

    Wills, Charlotte Page; Young, Megann; White, Douglas W

    2010-02-01

    This article illustrates the challenges practitioners face evaluating shortness of breath, a common emergency department complaint. Through a series of patient encounters, pitfalls in the evaluation of shortness of breath are reviewed and discussed. PMID:19945605

  19. Cardiovascular time courses during prolonged immersed static apnoea.

    PubMed

    Perini, Renza; Gheza, Alberto; Moia, Christian; Sponsiello, Nicola; Ferretti, Guido

    2010-09-01

    To define the dynamics of cardiovascular adjustments to apnoea during immersion, beat-to-beat heart rate (HR) and systolic (SBP) and diastolic (DBP) blood pressures were recorded in six divers during and after prolonged apnoeas while resting fully immersed in 27 degrees C water. Apnoeas lasted 215 +/- 35 s. Compared to control values, HR decreased by 20 beats min(-1) and SBP and DBP increased by 23 and 17 mmHg, respectively, in the initial 20 +/- 3 s (phase I). Both HR and BP remained stable during the following 92 +/- 15 s (phase II). Subsequently, during the final 103 +/- 29 s, SBP and DBP increased linearly to values about 60% higher than control, whereas HR remained unchanged (phase III). Cardiac output (Q') decreased by 35% in phase I and did not further change in phases II and III. Compared to control, total peripheral resistances were twice and three times higher than control, respectively, at the end of phases I and III. After resumption of breathing, HR and BP returned to control values in 5 and 30 s, respectively. The time courses of cardiovascular adjustments to immersed breath-holding indicated that cardiac response took place only at the beginning of apnoea. In contrast, vascular responses showed two distinct adjustments. This pattern suggests that the chronotropic control via the baroreflex is modified during apnoea. These cardiovascular changes during immersed static apnoea are in agreement with those already reported for static dry apnoeas.

  20. Haemodynamic modeling of the cardiovascular system using mock circulation loops to test cardiovascular devices.

    PubMed

    Timms, Daniel L; Gregory, Shaun D; Stevens, Michael C; Fraser, John F

    2011-01-01

    Comprehensive testing and evaluation of cardiovascular device function and performance is required prior to clinical implementation. Initial proof of concept investigations are conducted within in-vitro mock circulation loops, before proof of principle is demonstrated via in-vivo animal testing. To facilitate the rapid transition of cardiovascular devices through this development period, a testing apparatus was developed that closely models the natural human cardiovascular system haemodynamics. This mock circulation system accurately replicates cardiac function, coupled to systemic and pulmonary circulations. The physiological response produced by a number of clinical cardiovascular conditions can be actively controlled by variable parameters such as vascular resistance, arterial/venous compliance, ventricle contractility, heart rate, and heart /vascular volumes, while anatomical variations such as valve regurgitation and septal defects can be included. Auto-regulation of these parameters was attempted to reproduce the Frank-Starling mechanism, baroreceptor reflex, skeletal muscle pump, and postural changes. Steady state validation of loop performance was achieved by replicating the progression of a patient's clinical haemodynamics from heart failure, through VAD support, to heart transplantation. The system has been used to evaluate pulsatile and non-pulsatile ventricular assist devices, counter pulsation devices, non-invasive cardiac output monitors and cardiovascular stents. The interaction of these devices with the cardiovascular system was also investigated with regards to physiological control strategies and cannula placement. The system is a valuable tool for the accelerated progression of cardiovascular device development.

  1. 21 CFR 868.5620 - Breathing mouthpiece.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... connects with diagnostic or therapeutic respiratory devices. (b) Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5620 Breathing mouthpiece....

  2. The Air We Breathe. Activity Packet.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Environmental Protection, Hartford.

    This packet of materials is intended to provide teachers with an interdisciplinary approach to integrating air quality education into the existing curriculum of Connecticut schools. The unit is designed to complement the student booklet "The Air We Breathe," which is included. A major portion of the document is comprised of teaching activities.…

  3. Monitoring diurnal changes in exhaled human breath.

    PubMed

    Sinues, Pablo Martinez-Lozano; Kohler, Malcolm; Zenobi, Renato

    2013-01-01

    The development of noninvasive analytical techniques is of interest to the field of chronobiology, in order to reveal the human metabolome that seems to show temporal patterns and to predict internal body time. We report on the real-time mass spectrometric analysis of human breath as a potential method to be used in this field. The breath of 12 subjects was analyzed during 9 days by secondary electrospray ionization-mass spectrometry (SESI-MS). The samples were collected during four time slots: morning (8:00-11:00), before lunch (11:00-13:00), after lunch (13:00-15:00), and late afternoon (15:00-18:00). A total of 203 mass spectra were statistically analyzed. Univariate analysis revealed a number of features with a marked temporal behavior. Principal component analysis/canonical analysis showed a clear temporal evolution of the breath patterns. A blind cross-validation yielded 84% of correct classifications of the time slot at which the breath samples were collected. We conclude that this approach seems to have potential for the investigation of biological clocks, including the description of internal body time, which may have important implications for the timing of pharmacotherapy. PMID:23198821

  4. Air breathing direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming

    2002-01-01

    An air breathing direct methanol fuel cell is provided with a membrane electrode assembly, a conductive anode assembly that is permeable to air and directly open to atmospheric air, and a conductive cathode assembly that is permeable to methanol and directly contacting a liquid methanol source.

  5. Fast and Accurate Exhaled Breath Ammonia Measurement

    PubMed Central

    Solga, Steven F.; Mudalel, Matthew L.; Spacek, Lisa A.; Risby, Terence H.

    2014-01-01

    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations. PMID:24962141

  6. Coordination of breathing with nonrespiratory activities.

    PubMed

    Bartlett, Donald; Leiter, James C

    2012-04-01

    Many articles in this section of Comprehensive Physiology are concerned with the development and function of a central pattern generator (CPG) for the control of breathing in vertebrate animals. The action of the respiratory CPG is extensively modified by cortical and other descending influences as well as by feedback from peripheral sensory systems. The central nervous system also incorporates other CPGs, which orchestrate a wide variety of discrete and repetitive, voluntary and involuntary movements. The coordination of breathing with these other activities requires interaction and coordination between the respiratory CPG and those governing the nonrespiratory activities. Most of these interactions are complex and poorly understood. They seem to involve both conventional synaptic crosstalk between groups of neurons and fluid identity of neurons as belonging to one CPG or another: neurons that normally participate in breathing may be temporarily borrowed or hijacked by a competing or interrupting activity. This review explores the control of breathing as it is influenced by many activities that are generally considered to be nonrespiratory. The mechanistic detail varies greatly among topics, reflecting the wide variety of pertinent experiments.

  7. Crew equipment applications - Firefighter's Breathing System.

    NASA Technical Reports Server (NTRS)

    Smith, W. L.

    1973-01-01

    The Firefighter's Breathing System (FBS) represents a significant step in applying NASA's crew equipment technologists and technologies to civilian sector problems. This paper describes the problem, the utilization of user-design committees as a forum for development of design goals, the design of the FBS, and the field test program to be conducted.

  8. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American National Standards... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed...

  9. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American National Standards... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed...

  10. Cardiovascular pharmacogenomics: current status and future directions

    PubMed Central

    Roden, Dan M

    2016-01-01

    Drugs are widely used and highly effective in the treatment of heart disease. Nevertheless, in some instances, even drugs effective in a population display lack of efficacy or adverse drug reactions in individual patients, often in an apparently unpredictable fashion. This review summarizes the genomic factors now known to influence variability in responses to widely used cardiovascular drugs such as clopidogrel, warfarin, heparin and statins. Genomic approaches being used to discover new pathways in common cardiovascular diseases and thus potential new targets for drug development are described. Finally, the way in which this new information is likely to be used in an electronic medical record environment is discussed. PMID:26178435

  11. Introduction: Cardiovascular physics

    NASA Astrophysics Data System (ADS)

    Wessel, Niels; Kurths, Jürgen; Ditto, William; Bauernschmitt, Robert

    2007-03-01

    The number of patients suffering from cardiovascular diseases increases unproportionally high with the increase of the human population and aging, leading to very high expenses in the public health system. Therefore, the challenge of cardiovascular physics is to develop high-sophisticated methods which are able to, on the one hand, supplement and replace expensive medical devices and, on the other hand, improve the medical diagnostics with decreasing the patient's risk. Cardiovascular physics-which interconnects medicine, physics, biology, engineering, and mathematics-is based on interdisciplinary collaboration of specialists from the above scientific fields and attempts to gain deeper insights into pathophysiology and treatment options. This paper summarizes advances in cardiovascular physics with emphasis on a workshop held in Bad Honnef, Germany, in May 2005. The meeting attracted an interdisciplinary audience and led to a number of papers covering the main research fields of cardiovascular physics, including data analysis, modeling, and medical application. The variety of problems addressed by this issue underlines the complexity of the cardiovascular system. It could be demonstrated in this Focus Issue, that data analyses and modeling methods from cardiovascular physics have the ability to lead to significant improvements in different medical fields. Consequently, this Focus Issue of Chaos is a status report that may invite all interested readers to join the community and find competent discussion and cooperation partners.

  12. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... diver. (d) A primary breathing gas supply for SCUBA diving must be sufficient to support the diver for...) A diver-carried reserve breathing gas supply for SCUBA diving must be sufficient to allow the diver... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.340 Breathing gas supply. (a) A...

  13. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... diver. (d) A primary breathing gas supply for SCUBA diving must be sufficient to support the diver for...) A diver-carried reserve breathing gas supply for SCUBA diving must be sufficient to allow the diver... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.340 Breathing gas supply. (a) A...

  14. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation airflow will be measured in the facepiece or mouthpiece of open-circuit apparatus with air flowing at...

  15. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation airflow will be measured in the facepiece or mouthpiece of open-circuit apparatus with air flowing at...

  16. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation airflow will be measured in the facepiece or mouthpiece of open-circuit apparatus with air flowing at...

  17. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation airflow will be measured in the facepiece or mouthpiece of open-circuit apparatus with air flowing at...

  18. 46 CFR 108.703 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... DESIGN AND EQUIPMENT Miscellaneous Equipment § 108.703 Self-contained breathing apparatus. (a) Each unit must be equipped with a self-contained breathing apparatus described in § 108.497(a) to use as... 46 Shipping 4 2010-10-01 2010-10-01 false Self-contained breathing apparatus. 108.703 Section...

  19. 46 CFR 108.635 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.635 Self-contained breathing apparatus. Each locker or space containing self-contained breathing apparatus must be marked: “SELF CONTAINED... 46 Shipping 4 2011-10-01 2011-10-01 false Self-contained breathing apparatus. 108.635 Section...

  20. 46 CFR 108.635 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... DESIGN AND EQUIPMENT Equipment Markings and Instructions § 108.635 Self-contained breathing apparatus. Each locker or space containing self-contained breathing apparatus must be marked: “SELF CONTAINED... 46 Shipping 4 2010-10-01 2010-10-01 false Self-contained breathing apparatus. 108.635 Section...

  1. 46 CFR 169.736 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Self-contained breathing apparatus. 169.736 Section 169... VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.736 Self-contained breathing apparatus. Each locker or space containing self-contained breathing apparatus must be marked...

  2. 46 CFR 108.703 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... DESIGN AND EQUIPMENT Miscellaneous Equipment § 108.703 Self-contained breathing apparatus. (a) Each unit must be equipped with a self-contained breathing apparatus described in § 108.497(a) to use as... 46 Shipping 4 2011-10-01 2011-10-01 false Self-contained breathing apparatus. 108.703 Section...

  3. 46 CFR 169.736 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Self-contained breathing apparatus. 169.736 Section 169... VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.736 Self-contained breathing apparatus. Each locker or space containing self-contained breathing apparatus must be marked...

  4. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Breathing gas supply. 197.340 Section 197.340 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.340 Breathing gas supply. (a) A primary breathing gas supply for surface-supplied diving must be sufficient to support the following for...

  5. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Breathing gas supply. 197.340 Section 197.340 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.340 Breathing gas supply. (a) A primary breathing gas supply for surface-supplied diving must be sufficient to support the following for...

  6. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing gas mixer. 868.5330 Section 868.5330...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer. (a) Identification. A breathing gas mixer is a device intended for use in conjunction with a respiratory...

  7. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Breathing gas supply. 197.340 Section 197.340 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.340 Breathing gas supply. (a) A primary breathing gas supply for surface-supplied diving must be sufficient to support the following for...

  8. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing gas mixer. 868.5330 Section 868.5330...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer. (a) Identification. A breathing gas mixer is a device intended for use in conjunction with a respiratory...

  9. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing gas mixer. 868.5330 Section 868.5330...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer. (a) Identification. A breathing gas mixer is a device intended for use in conjunction with a respiratory...

  10. 21 CFR 868.5240 - Anesthesia breathing circuit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Anesthesia breathing circuit. 868.5240 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5240 Anesthesia breathing circuit. (a) Identification. An anesthesia breathing circuit is a device that is intended to administer medical gases to...

  11. 21 CFR 868.5240 - Anesthesia breathing circuit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Anesthesia breathing circuit. 868.5240 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5240 Anesthesia breathing circuit. (a) Identification. An anesthesia breathing circuit is a device that is intended to administer medical gases to...

  12. Human respiratory deposition of particles during oronasal breathing

    NASA Astrophysics Data System (ADS)

    Swift, David L.; Proctor, Donald F.

    Deposition of particles in the tracheobronchial and pulmonary airways is computed as a function of particle size, correcting for deposition in the parallel nasal and oral airways with oronasal breathing. Thoracic deposition is lower at all sizes for oronasal breathing than for mouth breathing via tube, and is negligible for aerodynamic equivalent diameters of 10 μm or larger.

  13. Oral Breathing Challenge in Participants with Vocal Attrition

    ERIC Educational Resources Information Center

    Sivasankar, Mahalakshmi; Fisher, Kimberly V.

    2003-01-01

    Vocal folds undergo osmotic challenge by mouth breathing during singing, exercising, and loud speaking. Just 15 min of obligatory oral breathing, to dry the vocal folds, increases phonation threshold pressure (P[subscript th]) and expiratory vocal effort in healthy speakers (M. Sivasankar & K. Fisher, 2002). We questioned whether oral breathing is…

  14. A convenient and reliable method for carbogen breathing in man.

    PubMed

    Kaanders, J H; van der Maazen, R W

    1993-12-01

    The feasibility of carbogen breathing and the intake of nicotinamide in combination with radiation therapy is currently being tested for clinical application. A dependable and convenient system for carbogen breathing is presented which can be easily combined with techniques for immobilization of the patient. The proposed method ensures adequate breathing of carbogen.

  15. 46 CFR 197.312 - Breathing supply hoses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The...

  16. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply hose is pressure tested prior to being placed into initial service and every 24 months thereafter to...

  17. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply hose is pressure tested prior to being placed into initial service and every 24 months thereafter to...

  18. 46 CFR 197.312 - Breathing supply hoses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The...

  19. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply hose is pressure tested prior to being placed into initial service and every 24 months thereafter to...

  20. 46 CFR 197.312 - Breathing supply hoses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The...

  1. 46 CFR 197.312 - Breathing supply hoses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The...

  2. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply hose is pressure tested prior to being placed into initial service and every 24 months thereafter to...

  3. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Breathing supply hoses. 197.456 Section 197.456 Shipping....456 Breathing supply hoses. (a) The diving supervisor shall insure that— (1) Each breathing supply hose is pressure tested prior to being placed into initial service and every 24 months thereafter to...

  4. 46 CFR 197.312 - Breathing supply hoses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Breathing supply hoses. 197.312 Section 197.312 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.312 Breathing supply hoses. (a) Each breathing supply hose must— (1) Have a maximum working pressure that is equal to or exceeds— (i) The...

  5. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  6. 42 CFR 84.115 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tubes; minimum requirements. 84.115 Section 84.115 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... § 84.115 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with...

  7. 42 CFR 84.132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tubes; minimum requirements. 84.132 Section 84.132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Respirators § 84.132 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction...

  8. 42 CFR 84.195 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tubes; minimum requirements. 84.195 Section 84.195 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Cartridge Respirators § 84.195 Breathing tubes; minimum requirements. Flexible breathing tubes used...

  9. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  10. 42 CFR 84.1132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tubes; minimum requirements. 84.1132 Section 84.1132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Gas Masks § 84.1132 Breathing tubes; minimum requirements. (a) Flexible breathing tubes used...

  11. 42 CFR 84.115 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tubes; minimum requirements. 84.115 Section 84.115 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... § 84.115 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with...

  12. 42 CFR 84.195 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.195 Section 84.195 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Cartridge Respirators § 84.195 Breathing tubes; minimum requirements. Flexible breathing tubes used...

  13. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  14. 42 CFR 84.1132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tubes; minimum requirements. 84.1132 Section 84.1132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Gas Masks § 84.1132 Breathing tubes; minimum requirements. (a) Flexible breathing tubes used...

  15. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  16. 42 CFR 84.195 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tubes; minimum requirements. 84.195 Section 84.195 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Cartridge Respirators § 84.195 Breathing tubes; minimum requirements. Flexible breathing tubes used...

  17. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  18. 42 CFR 84.1132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.1132 Section 84.1132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Gas Masks § 84.1132 Breathing tubes; minimum requirements. (a) Flexible breathing tubes used...

  19. 42 CFR 84.195 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tubes; minimum requirements. 84.195 Section 84.195 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Cartridge Respirators § 84.195 Breathing tubes; minimum requirements. Flexible breathing tubes used...

  20. 42 CFR 84.1132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tubes; minimum requirements. 84.1132 Section 84.1132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Gas Masks § 84.1132 Breathing tubes; minimum requirements. (a) Flexible breathing tubes used...

  1. 42 CFR 84.132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.132 Section 84.132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Respirators § 84.132 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction...

  2. 42 CFR 84.115 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tubes; minimum requirements. 84.115 Section 84.115 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... § 84.115 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with...

  3. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  4. 42 CFR 84.132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tubes; minimum requirements. 84.132 Section 84.132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Respirators § 84.132 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction...

  5. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  6. 42 CFR 84.132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tubes; minimum requirements. 84.132 Section 84.132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Respirators § 84.132 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction...

  7. 42 CFR 84.132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tubes; minimum requirements. 84.132 Section 84.132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Respirators § 84.132 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction...

  8. 42 CFR 84.115 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tubes; minimum requirements. 84.115 Section 84.115 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... § 84.115 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with...

  9. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  10. 42 CFR 84.152 - Breathing tube test; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing tube test; minimum requirements. 84.152... Respirators § 84.152 Breathing tube test; minimum requirements. (a)(1) Type A and Type B supplied-air respirators shall employ one or two flexible breathing tubes of the nonkinking type which extend from...

  11. 42 CFR 84.115 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing tubes; minimum requirements. 84.115 Section 84.115 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... § 84.115 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with...

  12. 42 CFR 84.172 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tubes; minimum requirements. 84.172... Air-Purifying Particulate Respirators § 84.172 Breathing tubes; minimum requirements. Flexible breathing tubes used in conjunction with respirators shall be designed and constructed to prevent:...

  13. 42 CFR 84.1132 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing tubes; minimum requirements. 84.1132 Section 84.1132 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Gas Masks § 84.1132 Breathing tubes; minimum requirements. (a) Flexible breathing tubes used...

  14. 42 CFR 84.195 - Breathing tubes; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing tubes; minimum requirements. 84.195 Section 84.195 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL... Cartridge Respirators § 84.195 Breathing tubes; minimum requirements. Flexible breathing tubes used...

  15. 42 CFR 84.90 - Breathing resistance test; inhalation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing resistance test; inhalation. 84.90...-Contained Breathing Apparatus § 84.90 Breathing resistance test; inhalation. (a) Resistance to inhalation... machine as described in § 84.88. (b) The inhalation resistance of open-circuit apparatus shall not...

  16. 42 CFR 84.90 - Breathing resistance test; inhalation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing resistance test; inhalation. 84.90...-Contained Breathing Apparatus § 84.90 Breathing resistance test; inhalation. (a) Resistance to inhalation... machine as described in § 84.88. (b) The inhalation resistance of open-circuit apparatus shall not...

  17. 42 CFR 84.90 - Breathing resistance test; inhalation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing resistance test; inhalation. 84.90...-Contained Breathing Apparatus § 84.90 Breathing resistance test; inhalation. (a) Resistance to inhalation... machine as described in § 84.88. (b) The inhalation resistance of open-circuit apparatus shall not...

  18. 42 CFR 84.90 - Breathing resistance test; inhalation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing resistance test; inhalation. 84.90...-Contained Breathing Apparatus § 84.90 Breathing resistance test; inhalation. (a) Resistance to inhalation... machine as described in § 84.88. (b) The inhalation resistance of open-circuit apparatus shall not...

  19. 42 CFR 84.90 - Breathing resistance test; inhalation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing resistance test; inhalation. 84.90...-Contained Breathing Apparatus § 84.90 Breathing resistance test; inhalation. (a) Resistance to inhalation... machine as described in § 84.88. (b) The inhalation resistance of open-circuit apparatus shall not...

  20. Improving estimation of cardiac vagal tone during spontaneous breathing using a paced breathing calibration.

    PubMed

    Wilhelm, Frank H; Grossman, Paul; Coyle, Michael A

    2004-01-01

    Respiratory sinus arrhythmia (RSA) is a commonly employed non-invasive measure of cardiac vagal control. It has been demonstrated that respiratory parameters such as tidal volume and respiratory frequency can change RSA without altering tonic vagal activity. Thus, within-individual comparisons of cardiac vagal control across different behavioral tasks might benefit from an adjustment for respiratory confounds. We tested an adjustment method using transfer function analysis and paced breathing at 3 different respiratory frequencies as the basis for regressing out respiratory related RSA changes in a task where breathing was not controlled. Electrocardiogram and calibrated respiration were recorded with the LifeShirt system from 15 young adult participants. Time series of RR intervals and lung volume change were computed and the respiration-to-RR-interval transfer-function magnitude (RSA-TF, in ms/liter) estimated. Mean (SD) of RSA-TF was 142 (68) at 9 breaths/min, 78 (52) at 13.5 breaths/min, 57 (43) at 18 breaths/min, and 121 (56) during baseline, with a respiratory frequency of 12.5 (3.8) breaths/min. At baseline, measured and predicted RSA-TF values (mean 94 +/- 82) differed significantly and correlated only moderately (r = 0.67). Factors contributing to a less than perfect correlation included slightly elevated subjective anxiety levels and hyperventilation during paced breathing, both of which may have affected cardiac vagal tone. This study demonstrates a novel procedure for computing a respiratory unrelated RSA index. Results provide some support for the utility of this adjustment method for improving the estimation of cardiac vagal tone from RSA, but also indicate that the paced breathing procedure may need to be further refined.

  1. Breath measurements as volatile organic compound biomarkers.

    PubMed Central

    Wallace, L; Buckley, T; Pellizzari, E; Gordon, S

    1996-01-01

    A brief review of the uses of breath analysis in studies of environmental exposure to volatile organic compounds (VOCs) is provided. The U.S. Environmental Protection Agency's large-scale Total Exposure Assessment Methodology Studies have measured concentrations of 32 target VOCs in the exhaled breath of about 800 residents of various U.S. cities. Since the previous 12-hr integrated personal air exposures to the same chemicals were also measured, the relation between exposure and body burden is illuminated. Another major use of the breath measurements has been to detect unmeasured pathways of exposure; the major impact of active smoking on exposure to benzene and styrene was detected in this way. Following the earlier field studies, a series of chamber studies have provided estimates of several important physiological parameters. Among these are the fraction, f, of the inhaled chemical that is exhaled under steady-state conditions and the residence times. tau i in several body compartments, which may be associated with the blood (or liver), organs, muscle, and fat. Most of the targeted VOCs appear to have similar residence times of a few minutes, 30 min, several hours, and several days in the respective tissue groups. Knowledge of these parameters can be helpful in estimating body burden from exposure or vice versa and in planning environmental studies, particularly in setting times to monitor breath in studies of the variation with time of body burden. Improvements in breath methods have made it possible to study short-term peak exposure situations such as filling a gas tank or taking a shower in contaminated water. PMID:8933027

  2. Effects of hypercapnia on variability of normal respiratory behavior in awake cats.

    PubMed

    Szlyk, P C; Jennings, D B

    1987-03-01

    Resting quiet awake cats breathing air in a steady state have a range of respiratory behavior, and this encompasses nonpurring and purring (D. B. Jennings and P. C. Szlyk, Can. J. Physiol. Pharmacol. 63: 148-154, 1985). On a given study day, individual cats usually breathed in a limited part of their potential respiratory range. Respiratory pattern, such as average breath frequency (f) and average tidal volume (VT) utilized for a given level of ventilation (V), could be predicted when cats breathed air; as well, inspiratory (TI) and expiratory (TE) times were specific for a given breath f. Inhalation of 2% and 4% CO2 in air caused an average increase in ventilation of 16 and 100%, respectively but breath-to-breath variability of V, f, and VT persisted at each fractional concentration of inspired CO2 (FICO2). The range of different V utilized breath to breath when breathing 2% CO2 overlapped with V during air control studies. Substantial overlap with control V also occurred in three of six cats when breathing 4% CO2. The most consistent effect of progressive hypercapnia was to increase VT and decrease f at a given level of V; increase in V during hypercapnia was accounted for by an increase in mean inspiratory flow (VT/TI). Hypercapnia also caused the fraction of breathing cycle devoted to inspiration (TI/TT) to increase at low f but not at high f.

  3. Testosterone and Cardiovascular Disease

    PubMed Central

    Tambo, Amos; Roshan, Mohsin H.K.; Pace, Nikolai P.

    2016-01-01

    Cardiovascular disease [CVD] is a leading cause of mortality accounting for a global incidence of over 31%. Atherosclerosis is the primary pathophysiology underpinning most types of CVD. Historically, modifiable and non-modifiable risk factors were suggested to precipitate CVD. Recently, epidemiological studies have identified emerging risk factors including hypotestosteronaemia, which have been associated with CVD. Previously considered in the realms of reproductive biology, testosterone is now believed to play a critical role in the cardiovascular system in health and disease. The actions of testosterone as they relate to the cardiac vasculature and its implication in cardiovascular pathology is reviewed. PMID:27014372

  4. Cardiovascular disease screening.

    PubMed

    Duffy, Jennifer Y; Hameed, Afshan B

    2015-06-01

    Cardiovascular disease is the leading cause of death amongst women worldwide. Cardiovascular risk assessment and primary prevention are important strategies to improve morbidity and mortality. In additional to the traditional risk factors, pregnancy complications such as pre-eclampsia and gestational diabetes increment future risk of developing cardiovascular complications. Additionally, several serum biomarkers are valuable measures for both risk assessment and predictors of clinical outcomes in women. The purpose of this review is to describe current risk stratification schemes as well as outline the role of obstetric history and serum biomarkers in adjusting risk stratification in women. PMID:26143091

  5. Snoring and breathing pauses during sleep: telephone interview survey of a United Kingdom population sample.

    PubMed Central

    Ohayon, M. M.; Guilleminault, C.; Priest, R. G.; Caulet, M.

    1997-01-01

    OBJECTIVES: To determine the prevalence of snoring, breathing pauses during sleep, and obstructive sleep apnoea syndrome and determine the relation between these events and sociodemographic variables, other health problems, driving accidents, and consumption of healthcare resources. DESIGN: Telephone interview survey directed by a previously validated computerised system (Sleep-Eval). SETTING: United Kingdom. SUBJECTS: 2894 women and 2078 men aged 15-100 years who formed a representative sample of the non-institutionalised population. MAIN OUTCOME MEASURES: Interview responses. RESULTS: Forty per cent of the population reported snoring regularly and 3.8% reported breathing pauses during sleep. Regular snoring was significantly associated with male sex, age 25 or more, obesity, daytime sleepiness or naps, night time awakenings, consuming large amounts of caffeine, and smoking. Breathing pauses during sleep were significantly associated with obstructive airways or thyroid disease, male sex, age 35-44 years, consumption of anxiety reducing drugs, complaints of non-restorative sleep, and consultation with a doctor in the past year. The two breathing symptoms were also significantly associated with drowsiness while driving. Based on minimal criteria of the International classification of Sleep Disorders (1990), 1.9% of the sample had obstructive sleep apnoea syndrome. In the 35-64 year age group 1.5% of women (95% confidence interval 0.8% to 2.2%) and 3.5% of men (2.4% to 4.6%) had obstructive sleep apnoea syndrome. CONCLUSIONS: Disordered breathing during sleep is widely underdiagnosed in the United Kingdom. The condition is linked to increased use of medical resources and a greater risk of daytime sleepiness, which augments the risk of accidents. Doctors should ask patients and bed partners regularly about snoring and breathing pauses during sleep. PMID:9093095

  6. Effect of tracheostomy tube on work of breathing: Comparison of pre- and post-decannulation

    PubMed Central

    Villalba, Darío; Feld, Viviana; Leiva, Valeria; Scrigna, Mariana; Distéfano, Eduardo; Pratto, Romina; Rodriguez, Matías; Collins, Jesica; Rocco, Ana; Matesa, Amelia; Rossi, Damián; Areas, Laura; Virgilio, Sacha; Golfarini, Nicolás; Gil-Rosetti, Gregorio; Diaz-Ballve, Pablo; Planells, Fernando

    2016-01-01

    Objective: To describe and compare the work of breathing (WOB) during spontaneous breathing under four conditions: (1) breathing through a tracheostomy tube with an inflated cuff, (2) breathing through the upper airway (UA) with a deflated cuff and occluded tube, (3) breathing through the UA with an occluded cuffless tube, and (4) postdecannulation. Patients and Methods: Patients who tolerated an occluded cuffless tube were included. Ventilatory variables and esophageal pressure were recorded. The pressure-time product (PTP), PTP/min, and PTP/min/tidal volume (PTP/min/VT) were measured. Each condition was measured for 5 min with a 15 min time interval between evaluations. Quantitative data are expressed as mean ± standard deviation. Single-factor analysis of variance was used, and the Games-Howell test was used for post hoc analysis of comparisons between group means (P ≤ 0.05). Results: Eight patients were studied under each of the four conditions described above. Statistically significant differences were found for PTP, PTP/min, and PTP/min/VT. In the post hoc analysis for PTP, significant differences among all conditions were found. For PTP/min, there was no significant difference between Conditions 2 and 4 (P = 0.138), and for PTP/min/VT, there was no significant difference between Conditions 1 and 2 (P = 0.072) or between Conditions 2 and 3 (P = 0.106). A trend toward a higher PTP, PTP/min, and PTP/min/VT was observed when breathing through a cuffless tracheostomy tube. Conclusion: The four conditions differed with respect to WOB. Cuff inflation could result in a reduced WOB because there is less dead space. Cuffless tracheostomy tubes generate increased WOB, perhaps due to the material deformity caused by body temperature. PMID:27722109

  7. Heart rate and blood pressure time courses during prolonged dry apnoea in breath-hold divers.

    PubMed

    Perini, Renza; Tironi, Adelaide; Gheza, Alberto; Butti, Ferdinando; Moia, Christian; Ferretti, Guido

    2008-09-01

    To define the dynamics of cardiovascular adjustments to apnoea, beat-to-beat heart rate (HR) and blood pressure and arterial oxygen saturation (SaO(2)) were recorded during prolonged breath-holding in air in 20 divers. Apnoea had a mean duration of 210 +/- 70 s. In all subjects, HR attained a value 14 beats min(-1) lower than control within the initial 30 s (phase I). HR did not change for the following 2-2.5 min (phase II). Then, nine subjects interrupted the apnoea (group A), whereas 11 subjects (group B) could prolong the breath-holding for about 100 s, during which HR continuously decreased (phase III). In both groups, mean blood pressure was 8 mmHg above control at the end of phase I; it then further increased by additional 12 mmHg at the end of the apnoea. In both groups, SaO(2) did not change in the initial 100-140 s of apnoea; then, it decreased to 95% at the end of phase II. In group B, SaO(2) further diminished to 84% at the end of phase III. A typical pattern of cardiovascular readjustments was identified during dry apnoea. This pattern was not compatible with a role for baroreflexes in phase I and phase II. Further readjustment in group B may imply a role for both baroreflexes and chemoreflexes. Hypothesis has been made that the end of phase II corresponds to physiological breakpoint.

  8. Sevoflurane degradation by soda lime in a circle breathing system.

    PubMed

    Munday, I T; Ward, P M; Foden, N D; Jones, R M; Van Pelt, F N; Kenna, J G

    1996-07-01

    Sevoflurane is degraded by soda lime to a vinyl ether commonly referred to as compound A. We measured the concentration of compound A in the circle breathing system of 31 patients receiving sevoflurane anaesthesia. Inspiratory and expiratory gas samples were analysed using gas chromatography and flame ionisation detection. The end-tidal sevoflurane concentration and soda lime temperature were recorded. The peak compound A concentration ranged between 10 to 32 ppm in the inspiratory limb and 7 to 26 ppm in the expiratory limb. There was a positive correlation between the peak compound A concentration and the end-tidal sevoflurane concentration (r2 = 0.545, p < 0.0001) and the soda lime temperature (r2 = 0.301, p = 0.0014). We conclude that the end-tidal concentration of sevoflurane and the temperature of the soda lime are important variables in determining concentration of compound A in a circle system.

  9. Nucleosome breathing and remodeling constrain CRISPR-Cas9 function.

    PubMed

    Isaac, R Stefan; Jiang, Fuguo; Doudna, Jennifer A; Lim, Wendell A; Narlikar, Geeta J; Almeida, Ricardo

    2016-04-28

    The CRISPR-Cas9 bacterial surveillance system has become a versatile tool for genome editing and gene regulation in eukaryotic cells, yet how CRISPR-Cas9 contends with the barriers presented by eukaryotic chromatin is poorly understood. Here we investigate how the smallest unit of chromatin, a nucleosome, constrains the activity of the CRISPR-Cas9 system. We find that nucleosomes assembled on native DNA sequences are permissive to Cas9 action. However, the accessibility of nucleosomal DNA to Cas9 is variable over several orders of magnitude depending on dynamic properties of the DNA sequence and the distance of the PAM site from the nucleosome dyad. We further find that chromatin remodeling enzymes stimulate Cas9 activity on nucleosomal templates. Our findings imply that the spontaneous breathing of nucleosomal DNA together with the action of chromatin remodelers allow Cas9 to effectively act on chromatin in vivo.

  10. Circadian rhythm of breath hydrogen in young women.

    PubMed

    Kagaya, M; Iwata, M; Toda, Y; Nakae, Y; Kondo, T

    1998-08-01

    Breath hydrogen levels, which reflect colonic fermentation of undigested starches, are usually low in the fasted state. Fasting levels of breath hydrogen are important for estimation of oro-cecal transit time and diagnosis of lactase deficiency. In young women, however, fasting levels of breath hydrogen are high. To clarify the reason for this, we studied the circadian pattern of breath hydrogen and the effect of alpha-D-galactosidase on fasting breath hydrogen in one study, and the effect of sleep deprivation on fasting breath hydrogen in another study, in 13 women students aged 21-23 years. In the first study, two breath samples were collected, one in the evening and the other the next morning. On another occasion, alpha-D-galactosidase was given before dinner and breath samples were collected the next morning. In the second study, the circadian rhythm of breath hydrogen was assessed for 3 days and the subjects were deprived of sleep on the second night. Breath samples were collected every 30 min, except during the second night when samples were collected at 1-h intervals. Fasting breath hydrogen was 24 +/- 3.9 ppm (mean +/- SE), which did not differ from the value for the previous night. Alpha-D-galactosidase significantly decreased fasting breath hydrogen levels, to 17 +/- 2.4 ppm (P < 0.05). There was a clear circadian pattern of breath hydrogen, high in the morning and decreasing to the nadir by 16:00. After dinner, the level increased again and stayed high during the night. Sleep deprivation did not affect fasting levels of breath hydrogen. High fasting breath hydrogen levels in young women followed a circadian pattern and this may have been due, in part, to an high intake of dietary fiber on the previous day. PMID:9719227

  11. Where to now in cardiovascular disease prevention.

    PubMed

    Najam, Osman; Ray, Kausik K

    2016-08-01

    Clinical trials have been instrumental in reducing the morbidity and mortality associated with cardiovascular disease, especially in the developed world. Recently however this improvement has plateaued, highlighting the importance of optimising current strategies and considering alternative practises. Inequalities in global healthcare, the changing patient profile as a result of an obesity and diabetes epidemic, and inadequate utilisation of evidence-based treatments are partly responsible. Despite pharmacotherapies such as statins having substantial evidence for cardiovascular benefit, patient response may be variable with genetic factors thought to be partly responsible. Although randomised controlled trials remain the backbone of clinical research, they have limitations including time taken to complete a trial and the financial costs associated with it. In this opinion-based paper, we discuss some of the key considerations for the future of cardiovascular disease prevention.

  12. [Resting heart rate and cardiovascular disease].

    PubMed

    Brito Díaz, Buenaventura; Alemán Sánchez, José Juan; Cabrera de León, Antonio

    2014-07-01

    Heart rate reflects autonomic nervous system activity. Numerous studies have demonstrated that an increased heart rate at rest is associated with cardiovascular morbidity and mortality as an independent risk factor. It has been shown a link between cardiac autonomic balance and inflammation. Thus, an elevated heart rate produces a micro-inflammatory response and is involved in the pathogenesis of endothelial dysfunction. In turn, decrease in heart rate produces benefits in congestive heart failure, myocardial infarction, atrial fibrillation, obesity, hyperinsulinemia, insulin resistance, and atherosclerosis. Alteration of other heart rate-related parameters, such as their variability and recovery after exercise, is associated with risk of cardiovascular events. Drugs reducing the heart rate (beta-blockers, calcium antagonists and inhibitors of If channels) have the potential to reduce cardiovascular events. Although not recommended in healthy subjects, interventions for reducing heart rate constitute a reasonable therapeutic goal in certain pathologies.

  13. Testosterone and Cardiovascular Disease.

    PubMed

    Kloner, Robert A; Carson, Culley; Dobs, Adrian; Kopecky, Stephen; Mohler, Emile R

    2016-02-01

    Testosterone (T) is the principal male sex hormone. As men age, T levels typically fall. Symptoms of low T include decreased libido, vasomotor instability, and decreased bone mineral density. Other symptoms may include depression, fatigue, erectile dysfunction, and reduced muscle strength/mass. Epidemiology studies show that low levels of T are associated with more atherosclerosis, coronary artery disease, and cardiovascular events. However, treating hypogonadism in the aging male has resulted in discrepant results in regard to its effect on cardiovascular events. Emerging studies suggest that T may have a future role in treating heart failure, angina, and myocardial ischemia. A large, prospective, long-term study of T replacement, with a primary endpoint of a composite of adverse cardiovascular events including myocardial infarction, stroke, and/or cardiovascular death, is needed. The Food and Drug Administration recently put additional restrictions on T replacement therapy labeling and called for additional studies to determine its cardiac safety. PMID:26846952

  14. Autophagy in cardiovascular biology

    PubMed Central

    Lavandero, Sergio; Chiong, Mario; Rothermel, Beverly A.; Hill, Joseph A.

    2015-01-01

    Cardiovascular disease is the leading cause of death worldwide. As such, there is great interest in identifying novel mechanisms that govern the cardiovascular response to disease-related stress. First described in failing hearts, autophagy within the cardiovascular system has been widely characterized in cardiomyocytes, cardiac fibroblasts, endothelial cells, vascular smooth muscle cells, and macrophages. In all cases, a window of optimal autophagic activity appears to be critical to the maintenance of cardiovascular homeostasis and function; excessive or insufficient levels of autophagic flux can each contribute to heart disease pathogenesis. In this Review, we discuss the potential for targeting autophagy therapeutically and our vision for where this exciting biology may lead in the future. PMID:25654551

  15. Autophagy in cardiovascular biology.

    PubMed

    Lavandero, Sergio; Chiong, Mario; Rothermel, Beverly A; Hill, Joseph A

    2015-01-01

    Cardiovascular disease is the leading cause of death worldwide. As such, there is great interest in identifying novel mechanisms that govern the cardiovascular response to disease-related stress. First described in failing hearts, autophagy within the cardiovascular system has been widely characterized in cardiomyocytes, cardiac fibroblasts, endothelial cells, vascular smooth muscle cells, and macrophages. In all cases, a window of optimal autophagic activity appears to be critical to the maintenance of cardiovascular homeostasis and function; excessive or insufficient levels of autophagic flux can each contribute to heart disease pathogenesis. In this Review, we discuss the potential for targeting autophagy therapeutically and our vision for where this exciting biology may lead in the future.

  16. [Cardiovascular prevention - 2016].

    PubMed

    Vértes, András; Szabados, Eszter

    2016-09-01

    Cardiovascular diseases are the main causes of premature death worldwide despite the fact that cardiovascular mortality decreased significantly in the last few decades in financially developed countries. This reduction is partly due to the modern medical and revascularisation treatments, and partly because of the effectiveness of prevention strategies such as lowering blood pressure and cholesterol level, as well as successful strategies against smoking. However, this positive trend is undermined by the striking growth in obesity and in type 2 diabetes mellitus, which could also be successfully controlled by lifestyle changes. This summary is based on an overview of the recent (2016) European Guideline for the Prevention of Cardiovascular Diseases. Here the authors describe preventive strategies and goals to be achieved, the most important lifestyle suggestions, and the secondary prevention medical treatment for patients with already established cardiovascular disease. Orv. Hetil., 2016, 157(38), 1526-1531. PMID:27640620

  17. [Cardiovascular risk among firefighters].

    PubMed

    Serra, A

    2012-01-01

    Firefighting is a high-hazard job for hearth disease, smoke exposure, physical exertion, psychological stressors and noise increase cardiovascular risk among fire fighters. In U.S.A. during the period 1984-2011 45% of on-duty fire fighter fatalities were due to sudden cardiac death. However numerous mortality studies have not shown consistent evidence of an increased risk of cardiovascular diseases. In Italy fire fighters, burdened with elevated cardiovascular risk and psycho-physical demand, have entry-level and periodic medical evaluations. For these workers wellness/fitness programs, strategies aimed to reduce cardiovascular risk factors and fitness evaluations to ensure that are physically capable of performing the essential job tasks of their profession should be encouraged. PMID:23405620

  18. Cocaine and Cardiovascular Events.

    ERIC Educational Resources Information Center

    Cantwell, John D.; Rose, Fred D.

    1986-01-01

    The case of a 21-year-old man who suffered a myocardial infarction after using cocaine and amphetamines is reported. A brief literature review provides evidence of cocaine's potential cardiovascular effects. (Author/MT)

  19. [Cardiovascular syphilis: diagnosis, treatment].

    PubMed

    Carrada-Bravo, Teodoro

    2006-01-01

    Cardiovascular tertiary syphilis may lead to aortitis, aortic aneurism, coronary stenosis, aortic insufficiency and, rarely, to myocarditis. The physician must be familiar with the clinical presentations of this process, including the asymptomatic variety and must be able to have an organized plan for the diagnosis and evaluation to establish or exclude the presence of cardiovascular pathology and the differential diagnosis with other entities. Once the etiologic and topographic diagnosis is established, the patient should be treated with penicillin, doxicycline and other antibiotics, and the consequences of the disorder, both actual and potential, should be considered before deciding weather to recommend surgical intervention. Although late syphilis can be prevented by appropriate therapy of early syphilis, this is a cardiovascular disease that most likely will continue to be diagnosed lately. Understanding of the pathology and pathophysiology of the disease, is most important for its prompt recognition and subsequent management. This paper reviews the natural history, diagnosis and therapy of cardiovascular syphilis. PMID:17469346

  20. Understanding cardiovascular disease

    MedlinePlus

    ... of plaque. Narrow arteries reduce or block blood flow. When blood and oxygen can't get to the legs, it can injure nerves and tissue. High blood pressure (hypertension) is a cardiovascular disease that ...

  1. Violence and Cardiovascular Health

    PubMed Central

    Suglia, Shakira F.; Sapra, Katherine J.; Koenen, Karestan C.

    2014-01-01

    Context Violence, experienced in either childhood or adulthood, has been associated with physical health outcomes including cardiovascular disease. However, the consistency of the existing literature has not been evaluated. Evidence acquisition In 2013, the authors conducted a PubMed and Web of Science review of peer reviewed articles published prior to August 2013 on the relation between violence exposure, experienced in either childhood or adulthood, and cardiovascular outcomes. To meet inclusion criteria, articles had to present estimates for the relation between violence exposure and cardiovascular outcomes (hypertension, blood pressure, stroke, coronary disease, or myocardial infarction) adjusted for demographic factors. Articles focusing on violence from TV, video games, natural disasters, terrorism, or war were excluded. Evidence synthesis The initial search yielded 2,273 articles; after removing duplicates and applying inclusion and exclusion criteria, 30 articles were selected for review. A consistent positive relation was noted on the association between violence experienced during childhood and cardiovascular outcomes in adulthood (i.e., hypertension, coronary heart disease, and myocardial infarction). Associations across genders with varying types of violence exposure were also noted. By contrast, findings were mixed on the relation between adult violence exposure and cardiovascular outcome. Conclusions Despite varying definitions of violence exposure and cardiovascular endpoints, a consistent relation exists between childhood violence exposure, largely assessed retrospectively, and cardiovascular endpoints. Findings are mixed for the adult violence–cardiovascular health relation. The cross-sectional nature of most adult studies and the reliance of self-reported outcomes can potentially be attributed to the lack of findings among adult violence exposure studies. PMID:25599905

  2. Cardiovascular information systems.

    PubMed

    Marion, Joe

    2012-01-01

    The ARRA/HITECH Act has made electronic medical records a front burner issue, and many believe that EMRs will make departmental systems redundant. Some cardiologists beg to differ, arguing that cardiovascular information systems are deeply clinical and essential to the cardiovascular workflow. Here's a look at the evolution of CVIS, EMR, and their roles as the healthcare landscape is being transformed by meaningful use.

  3. Cardiovascular Effects of Caffeine

    PubMed Central

    Myers, Martin G.

    1992-01-01

    A review of the literature on the cardiovascular effects of caffeine indicates that moderate caffeine consumption does not cause cardiac arrhythmias, hypertension, or an increased incidence of coronary heart disease. Caffeine use is often associated with atherogenic behavior, such as cigarette smoking. Failure to take into account covariables for cardiovascular disease could be responsible for commonly held misconceptions about caffeine and heart disease. PMID:21221403

  4. Metabolite Content Profiling of Bottlenose Dolphin Exhaled Breath

    PubMed Central

    2014-01-01

    Changing ocean health and the potential impact on marine mammal health are gaining global attention. Direct health assessments of wild marine mammals, however, is inherently difficult. Breath analysis metabolomics is a very attractive assessment tool due to its noninvasive nature, but it is analytically challenging. It has never been attempted in cetaceans for comprehensive metabolite profiling. We have developed a method to reproducibly sample breath from small cetaceans, specifically Atlantic bottlenose dolphins (Tursiops truncatus). We describe the analysis workflow to profile exhaled breath metabolites and provide here a first library of volatile and nonvolatile compounds in cetacean exhaled breath. The described analytical methodology enabled us to document baseline compounds in exhaled breath of healthy animals and to study changes in metabolic content of dolphin breath with regard to a variety of factors. The method of breath analysis may provide a very valuable tool in future wildlife conservation efforts as well as deepen our understanding of marine mammals biology and physiology. PMID:25254551

  5. Heart Rate and Systolic Blood Pressure Variability in the Time Domain in Patients with Recent and Long-Standing Diabetes Mellitus.

    PubMed

    Rivera, Ana Leonor; Estañol, Bruno; Sentíes-Madrid, Horacio; Fossion, Ruben; Toledo-Roy, Juan C; Mendoza-Temis, Joel; Morales, Irving O; Landa, Emmanuel; Robles-Cabrera, Adriana; Moreno, Rene; Frank, Alejandro

    2016-01-01

    Diabetes Mellitus (DM) affects the cardiovascular response of patients. To study this effect, interbeat intervals (IBI) and beat-to-beat systolic blood pressure (SBP) variability of patients during supine, standing and controlled breathing tests were analyzed in the time domain. Simultaneous noninvasive measurements of IBI and SBP for 30 recently diagnosed and 15 long-standing DM patients were compared with the results for 30 rigorously screened healthy subjects (control). A statistically significant distinction between control and diabetic subjects was provided by the standard deviation and the higher moments of the distributions (skewness, and kurtosis) with respect to the median. To compare IBI and SBP for different populations, we define a parameter, α, that combines the variability of the heart rate and the blood pressure, as the ratio of the radius of the moments for IBI and the same radius for SBP. As diabetes evolves, α decreases, standard deviation of the IBI detrended signal diminishes (heart rate signal becomes more "rigid"), skewness with respect to the median approaches zero (signal fluctuations gain symmetry), and kurtosis increases (fluctuations concentrate around the median). Diabetes produces not only a rigid heart rate, but also increases symmetry and has leptokurtic distributions. SBP time series exhibit the most variable behavior for recently diagnosed DM with platykurtic distributions. Under controlled breathing, SBP has symmetric distributions for DM patients, while control subjects have non-zero skewness. This may be due to a progressive decrease of parasympathetic and sympathetic activity to the heart and blood vessels as diabetes evolves.

  6. Heart Rate and Systolic Blood Pressure Variability in the Time Domain in Patients with Recent and Long-Standing Diabetes Mellitus.

    PubMed

    Rivera, Ana Leonor; Estañol, Bruno; Sentíes-Madrid, Horacio; Fossion, Ruben; Toledo-Roy, Juan C; Mendoza-Temis, Joel; Morales, Irving O; Landa, Emmanuel; Robles-Cabrera, Adriana; Moreno, Rene; Frank, Alejandro

    2016-01-01

    Diabetes Mellitus (DM) affects the cardiovascular response of patients. To study this effect, interbeat intervals (IBI) and beat-to-beat systolic blood pressure (SBP) variability of patients during supine, standing and controlled breathing tests were analyzed in the time domain. Simultaneous noninvasive measurements of IBI and SBP for 30 recently diagnosed and 15 long-standing DM patients were compared with the results for 30 rigorously screened healthy subjects (control). A statistically significant distinction between control and diabetic subjects was provided by the standard deviation and the higher moments of the distributions (skewness, and kurtosis) with respect to the median. To compare IBI and SBP for different populations, we define a parameter, α, that combines the variability of the heart rate and the blood pressure, as the ratio of the radius of the moments for IBI and the same radius for SBP. As diabetes evolves, α decreases, standard deviation of the IBI detrended signal diminishes (heart rate signal becomes more "rigid"), skewness with respect to the median approaches zero (signal fluctuations gain symmetry), and kurtosis increases (fluctuations concentrate around the median). Diabetes produces not only a rigid heart rate, but also increases symmetry and has leptokurtic distributions. SBP time series exhibit the most variable behavior for recently diagnosed DM with platykurtic distributions. Under controlled breathing, SBP has symmetric distributions for DM patients, while control subjects have non-zero skewness. This may be due to a progressive decrease of parasympathetic and sympathetic activity to the heart and blood vessels as diabetes evolves. PMID:26849653

  7. Breath Analysis Using Laser Spectroscopic Techniques: Breath Biomarkers, Spectral Fingerprints, and Detection Limits

    PubMed Central

    Wang, Chuji; Sahay, Peeyush

    2009-01-01

    Breath analysis, a promising new field of medicine and medical instrumentation, potentially offers noninvasive, real-time, and point-of-care (POC) disease diagnostics and metabolic status monitoring. Numerous breath biomarkers have been detected and quantified so far by using the GC-MS technique. Recent advances in laser spectroscopic techniques and laser sources have driven breath analysis to new heights, moving from laboratory research to commercial reality. Laser spectroscopic detection techniques not only have high-sensitivity and high-selectivity, as equivalently offered by the MS-based techniques, but also have the advantageous features of near real-time response, low instrument costs, and POC function. Of the approximately 35 established breath biomarkers, such as acetone, ammonia, carbon dioxide, ethane, methane, and nitric oxide, 14 species in exhaled human breath have been analyzed by high-sensitivity laser spectroscopic techniques, namely, tunable diode laser absorption spectroscopy (TDLAS), cavity ringdown spectroscopy (CRDS), integrated cavity output spectroscopy (ICOS), cavity enhanced absorption spectroscopy (CEAS), cavity leak-out spectroscopy (CALOS), photoacoustic spectroscopy (PAS), quartz-enhanced photoacoustic spectroscopy (QEPAS), and optical frequency comb cavity-enhanced absorption spectroscopy (OFC-CEAS). Spectral fingerprints of the measured biomarkers span from the UV to the mid-IR spectral regions and the detection limits achieved by the laser techniques range from parts per million to parts per billion levels. Sensors using the laser spectroscopic techniques for a few breath biomarkers, e.g., carbon dioxide, nitric oxide, etc. are commercially available. This review presents an update on the latest developments in laser-based breath analysis. PMID:22408503

  8. Noninvasive Measurement of Plasma Triglycerides and Free Fatty Acids from Exhaled Breath

    PubMed Central

    Minh, Timothy Do Chau; Oliver, Stacy R; Flores, Rebecca L; Ngo, Jerry; Meinardi, Simone; Carlson, Matthew K; Midyett, Jason; Rowland, F Sherwood; Blake, Donald R; Galassetti, Pietro Renato

    2012-01-01

    Background Although altered metabolism has long been known to affect human breath, generating clinically usable metabolic tests from exhaled compounds has proven challenging. If developed, a breath-based lipid test would greatly simplify management of diabetes and serious pathological conditions (e.g., obesity, familial hyperlipidemia, and coronary artery disease), in which systemic lipid levels are a critical risk factor for onset and development of future cardiovascular events. Methods We, therefore, induced controlled fluctuations of plasma lipids (insulin-induced lipid suppression or intravenous infusion of Intralipid) during 4-h in vivo experiments on 23 healthy volunteers (12 males/11 females, 28.0 ± 0.3 years) to find correlations between exhaled volatile organic compounds and plasma lipids. In each subject, plasma triglycerides (TG) and free fatty acids (FFA) concentrations were both directly measured and calculated via individualized prediction equations based on the multiple linear regression analysis of a cluster of 4 gases. In the lipid infusion protocol, we also generated common prediction equations using a maximum of 10 gases. Results This analysis yielded strong correlations between measured and predicted values during both lipid suppression (r = 0.97 for TG; r = 0.90 for FFA) and lipid infusion (r = 0.97 for TG; r = 0.94 for FFA) studies. In our most accurate common prediction model, measured and predicted TG and FFA values also displayed very strong statistical agreement (r = 0.86 and r = 0.81, respectively). Conclusions Our results demonstrate the feasibility of measuring plasma lipids through breath analysis. Optimization of this technology may ultimately lead to the development of portable breath analyzers for plasma lipids, replacing blood-based bioassays. PMID:22401327

  9. Coordination-related changes in the rhythms of breathing and walking in humans.

    PubMed

    Rassler, B; Kohl, J

    2000-07-01

    Coordination of the respiratory rhythm with the rhythm of limb movements has often been observed during rhythmical exercise (e.g. in locomotion). It is usually associated with changes in the respiratory time course, but not in the locomotor rhythm. Therefore, we hypothesised that in walking, the extent of coordination-related changes (CRC) in respiratory parameters would increase with closer coordination. With respect to the controversially discussed question of a possible energetic advantage due to coordination, we devoted particular interest to the CRC in oxygen uptake (VO2). In addition, we investigated the incidence and the extent of CRC in the stepping rhythm. We examined 18 volunteers walking on a treadmill at three different workload levels, which were adjusted by altering either the velocity or slope of the treadmill. Each walking test was carried out twice, once with spontaneous breathing and once with breathing paced by a step-related acoustic signal to enhance the coordination between breathing and walking. No correlation was found between the CRC in the analysed parameters and the degree of coordination. However, the extent of CRC of ventilation and VO2 decreased with increasing workload. With the transition to coordination, increases and decreases of VO2 occurred about equally often. From this we conclude that energetic economisation in walking, as reflected by a reduction in VO2, is rather a side-effect of coordination, and is probably due to a more precise regulation of the breathing pattern. The economisation was more pronounced at higher work loads than at lower work loads. Our results revealed that coordination is also associated with changes in the stepping rate, which occurred more frequently when the variability of breathing was restricted by acoustic pacing of the breathing rhythm. This finding suggests that the choice of walking rhythm is not completely free, but can be influenced by the breathing rhythm. CRC in the walking rhythm might

  10. Characterization of exhaled breath particles collected by an electret filter technique.

    PubMed

    Tinglev, Åsa Danielsson; Ullah, Shahid; Ljungkvist, Göran; Viklund, Emilia; Olin, Anna-Carin; Beck, Olof

    2016-06-01

    Aerosol particles that are present in exhaled breath carry nonvolatile components and have gained interest as a specimen for potential biomarkers. Nonvolatile compounds detected in exhaled breath include both endogenous and exogenous compounds. The aim of this study was to study particles collected with a new, simple and convenient filter technique. Samples of breath were collected from healthy volunteers from approximately 30 l of exhaled air. Particles were counted with an optical particle counter and two phosphatidylcholines were measured by liquid chromatography-tandem mass spectrometry. In addition, phosphatidylcholines and methadone was analysed in breath from patients in treatment with methadone and oral fluid was collected with the Quantisal device. The results demonstrated that the majority of particles are  <1 μm in size and that the fraction of larger particle contributes most to the total mass. The phosphatidylcholine PC(16 : 0/16 : 0) dominated over PC(16 : 0/18 : 1) and represented a major constituent of the particles. The concentration of the PC(16 : 0/16 : 0) homolog was significantly correlated (p  <  0.001) with total mass. From the low concentration of the two phosphatidylcholines and their relative abundance in oral fluid a major contribution from the oral cavity could be ruled out. The concentration of PC(16 : 0/16 : 0) in breath was positively correlated with age (p  <  0.01). An attempt to use PC(16 : 0/16 : 0) as a sample size indicator for methadone was not successful, as the large intra-individual variability between samplings even increased after normalization. In conclusion, it was demonstrated that exhaled breath sampled with the filter device represents a specimen corresponding to surfactant. The possible use of PC(16 : 0/16 : 0) as a sample size indicator was supported and deserves further investigations. We propose that the direct and selective collection of the breath aerosol particles is a promising strategy

  11. [Cardiovascular risk factors in young people].

    PubMed

    Sánchez-Contreras, Mónica; Moreno-Gómez, Germán A; Marín-Grisales, Marta E; García-Ortiz, Luis H

    2009-01-01

    Cardiovascular disease (CVD) involves several disorders related to the formation and development of atherosclerotic processes. Several risk factors are involved in CVD aetiology; some of them (i.e. age, hypertension, obesity, dislipidemia and diabetes) have been clearly associated, whereas others have a variable level of association. An increase in cardiovascular risk factors has been recently reported in the young population; studies of cardiovascular risk factors in this population have shown that its cardiovascular risk profile could be different from that presented by older populations. This review presents a summary of reported cardiovascular risk factors in the young population and their causes which have been released and indexed in different databases. Most factors discussed are life-habit risk factors and represent direct targets for clinical intervention. We propose that primary CVD prevention should include a more detailed knowledge of the nature of the risk factors concerning the young population and could have a positive impact on CVD prevalence during the next few years.

  12. Sleep-disordered breathing and psychiatric disorders.

    PubMed

    Naqvi, Haider A; Wang, David; Glozier, Nicholas; Grunstein, Ronald R

    2014-12-01

    Sleep-disordered breathing, the commonest form of which is obstructive sleep apnoea (OSA) is increasingly recognised as a treatable cause of morbidity. It shares many risk factors with psychiatric disorders including behaviours such as smoking and physical comorbidity. Many symptoms of the two overlap, leaving OSA often undetected and undertreated. In the few studies that assess the two, OSA is commonly comorbid with depression (17-45%) and schizophrenia (up to 55%) and possibly bipolar. There is some limited evidence that treating OSA can ameliorate psychiatric symptoms. Some psychotropics, such as narcotics, cause sleep-disordered breathing (SDB), whilst weight-inducing neuroleptics may exacerbate it. An extreme form of SDB, sudden infant death syndrome (SIDS), is a risk in mothers with substance abuse. Being aware of these common comorbidities may help improve psychiatric patient's treatment and quality of life. PMID:25308389

  13. Weyl magnons in breathing pyrochlore antiferromagnets.

    PubMed

    Li, Fei-Ye; Li, Yao-Dong; Kim, Yong Baek; Balents, Leon; Yu, Yue; Chen, Gang

    2016-01-01

    Frustrated quantum magnets not only provide exotic ground states and unusual magnetic structures, but also support unconventional excitations in many cases. Using a physically relevant spin model for a breathing pyrochlore lattice, we discuss the presence of topological linear band crossings of magnons in antiferromagnets. These are the analogues of Weyl fermions in electronic systems, which we dub Weyl magnons. The bulk Weyl magnon implies the presence of chiral magnon surface states forming arcs at finite energy. We argue that such antiferromagnets present a unique example, in which Weyl points can be manipulated in situ in the laboratory by applied fields. We discuss their appearance specifically in the breathing pyrochlore lattice, and give some general discussion of conditions to find Weyl magnons, and how they may be probed experimentally. Our work may inspire a re-examination of the magnetic excitations in many magnetically ordered systems. PMID:27650053

  14. Weyl magnons in breathing pyrochlore antiferromagnets

    NASA Astrophysics Data System (ADS)

    Li, Fei-Ye; Li, Yao-Dong; Kim, Yong Baek; Balents, Leon; Yu, Yue; Chen, Gang

    2016-09-01

    Frustrated quantum magnets not only provide exotic ground states and unusual magnetic structures, but also support unconventional excitations in many cases. Using a physically relevant spin model for a breathing pyrochlore lattice, we discuss the presence of topological linear band crossings of magnons in antiferromagnets. These are the analogues of Weyl fermions in electronic systems, which we dub Weyl magnons. The bulk Weyl magnon implies the presence of chiral magnon surface states forming arcs at finite energy. We argue that such antiferromagnets present a unique example, in which Weyl points can be manipulated in situ in the laboratory by applied fields. We discuss their appearance specifically in the breathing pyrochlore lattice, and give some general discussion of conditions to find Weyl magnons, and how they may be probed experimentally. Our work may inspire a re-examination of the magnetic excitations in many magnetically ordered systems.

  15. Protective supplied-breathing-air garment

    DOEpatents

    Childers, E.L.; von Hortenau, E.F.

    1982-05-28

    A breathing-air garment for isolating a wearer from hostile environments containing toxins or irritants is disclosed. The garment includes a suit and a separate head-protective enclosure or hood engaging a suit collar in sealing attachment. The hood and suit collar are cylindrically shaped and dimensioned to enable the wearer to withdraw his hands from the suit sleeves to perform manual tasks within the hood interior. Breathing air is supplied from an external air line with an air-delivery hose attached to the hood interior. The hose feeds air into an annular halo-like fiber-filled plenum having spaced discharge orifices attached to the hood top wall. A plurality of air exhaust/check valves located at the suit extremities cooperate with the hood air-delivery system to provide a cooling flow of circulating air from the hood throughout the suit interior. A suit entry seal provided on the suit sealed with an adhesive sealing flap.

  16. Weyl magnons in breathing pyrochlore antiferromagnets

    PubMed Central

    Li, Fei-Ye; Li, Yao-Dong; Kim, Yong Baek; Balents, Leon; Yu, Yue; Chen, Gang

    2016-01-01

    Frustrated quantum magnets not only provide exotic ground states and unusual magnetic structures, but also support unconventional excitations in many cases. Using a physically relevant spin model for a breathing pyrochlore lattice, we discuss the presence of topological linear band crossings of magnons in antiferromagnets. These are the analogues of Weyl fermions in electronic systems, which we dub Weyl magnons. The bulk Weyl magnon implies the presence of chiral magnon surface states forming arcs at finite energy. We argue that such antiferromagnets present a unique example, in which Weyl points can be manipulated in situ in the laboratory by applied fields. We discuss their appearance specifically in the breathing pyrochlore lattice, and give some general discussion of conditions to find Weyl magnons, and how they may be probed experimentally. Our work may inspire a re-examination of the magnetic excitations in many magnetically ordered systems. PMID:27650053

  17. More air-breathing spaceplane projects

    NASA Astrophysics Data System (ADS)

    Holmes, Diane L.

    1989-08-01

    The development and funding of current air-breathing spaceplane projects are discussed. The research considered includes: West Germany's Saenger, the UK's Hotol, the US's NASP, India's hyperplane, and the hypersonic activities of France, Japan, and the USSR. The basic characteristics of a spaceplace are: a reduction in launch costs, reusability, easier ground operations and launch preparation, short turnaround times, horizontal take-off and landing, and reliability and safety. Various types of power-plant concepts for the spaceplane, such as turbojet, ramjet, and scramjet, are described and diagrams are presented. The design of the airframe, aerodynamic heating, payload capacity, and the cost for developing an air-breathing spaceplane are examined. Applications for the spaceplane are proposed.

  18. Respiratory disease and cardiovascular morbidity

    PubMed Central

    Koskela, R; Mutanen, P; Sorsa, J; Klockars, M

    2005-01-01

    Background: Work related dust exposure is a risk factor for acute and chronic respiratory irritation and inflammation. Exposure to dust and cigarette smoke predisposes to exogenous viral and bacterial infections of the respiratory tract. Respiratory infection can also act as a risk factor in the development of atherosclerotic and coronary artery disease. Aims: To investigate the association of dust exposure and respiratory diseases with ischaemic heart disease (IHD) and other cardiovascular diseases (CVDs). Methods: The study comprised 6022 dust exposed (granite, foundry, cotton mill, iron foundry, metal product, and electrical) workers hired in 1940–76 and followed until the end of 1992. National mortality and morbidity registers and questionnaires were used. The statistical methods were person-year analysis and Cox regression. Results: Co-morbidity from cardiovascular and respiratory diseases ranged from 17% to 35%. In at least 60% of the co-morbidity cases a respiratory disease preceded a cardiovascular disease. Chronic bronchitis, pneumonia, and upper respiratory track infections predicted IHD in granite workers (rate ratio (RR) = 1.9; 95% CI 1.38 to 2.72), foundry workers (2.1; 1.48 to 2.93), and iron foundry workers (1.7; 1.16 to 2.35). Dust exposure was not a significant predictor of IHD or other CVD in any group. Dust exposure was related to respiratory morbidity. Thus, some respiratory diseases appeared to act as intermediate variables in the association of dust exposure with IHD. Conclusion: Dust exposure had only a small direct effect on IHD and other CVD. IHD morbidity was associated with preceding respiratory morbidity. A chronic infectious respiratory tract disease appeared to play an independent role in the development of IHD. PMID:16109822

  19. Introduction to Cardiovascular Magnetic Resonance: Technical Principles and Clinical Applications

    PubMed Central

    Tseng, Wen-Yih Isaac; Su, Mao-Yuan Marine; Tseng, Yao-Hui Elton

    2016-01-01

    Cardiovascular magnetic resonance (CMR) is a set of magnetic resonance imaging (MRI) techniques designed to assess cardiovascular morphology, ventricular function, myocardial perfusion, tissue characterization, flow quantification and coronary artery disease. Since MRI is a non-invasive tool and free of radiation, it is suitable for longitudinal monitoring of treatment effect and follow-up of disease progress. Compared to MRI of other body parts, CMR faces specific challenges from cardiac and respiratory motion. Therefore, CMR requires synchronous cardiac and respiratory gating or breath-holding techniques to overcome motion artifacts. This article will review the basic principles of MRI and introduce the CMR techniques that can be optimized for enhanced clinical assessment. PMID:27122944

  20. State-dependent control of breathing by the retrotrapezoid nucleus

    PubMed Central

    Burke, Peter GR; Kanbar, Roy; Basting, Tyler M; Hodges, Walter M; Viar, Kenneth E; Stornetta, Ruth L; Guyenet, Patrice G

    2015-01-01

    Key points This study explores the state dependence of the hypercapnic ventilatory reflex (HCVR). We simulated an instantaneous increase or decrease of central chemoreceptor activity by activating or inhibiting the retrotrapezoid nucleus (RTN) by optogenetics in conscious rats. During quiet wake or non-REM sleep, hypercapnia increased both breathing frequency (fR) and tidal volume (VT) whereas, in REM sleep, hypercapnia increased VT exclusively. Optogenetic inhibition of RTN reduced VT in all sleep–wake states, but reduced fR only during quiet wake and non-REM sleep. RTN stimulation always increased VT but raised fR only in quiet wake and non-REM sleep. Phasic RTN stimulation produced active expiration and reduced early expiratory airflow (i.e. increased upper airway resistance) only during wake. We conclude that the HCVR is highly state-dependent. The HCVR is reduced during REM sleep because fR is no longer under chemoreceptor control and thus could explain why central sleep apnoea is less frequent in REM sleep. Abstract Breathing has different characteristics during quiet wake, non-REM or REM sleep, including variable dependence on . We investigated whether the retrotrapezoid nucleus (RTN), a proton-sensitive structure that mediates a large portion of the hypercapnic ventilatory reflex, regulates breathing differently during sleep vs. wake. Electroencephalogram, neck electromyogram, blood pressure, respiratory frequency (fR) and tidal volume (VT) were recorded in 28 conscious adult male Sprague–Dawley rats. Optogenetic stimulation of RTN with channelrhodopsin-2, or inhibition with archaerhodopsin, simulated an instantaneous increase or decrease of central chemoreceptor activity. Both opsins were delivered with PRSX8-promoter-containing lentiviral vectors. RTN and catecholaminergic neurons were transduced. During quiet wake or non-REM sleep, hypercapnia (3 or 6% ) increased both fR and VT whereas, in REM sleep, hypercapnia increased VT exclusively. RTN

  1. Breath tests and irritable bowel syndrome.

    PubMed

    Rana, Satya Vati; Malik, Aastha

    2014-06-28

    Breath tests are non-invasive tests and can detect H₂ and CH₄ gases which are produced by bacterial fermentation of unabsorbed intestinal carbohydrate and are excreted in the breath. These tests are used in the diagnosis of carbohydrate malabsorption, small intestinal bacterial overgrowth, and for measuring the orocecal transit time. Malabsorption of carbohydrates is a key trigger of irritable bowel syndrome (IBS)-type symptoms such as diarrhea and/or constipation, bloating, excess flatulence, headaches and lack of energy. Abdominal bloating is a common nonspecific symptom which can negatively impact quality of life. It may reflect dietary imbalance, such as excess fiber intake, or may be a manifestation of IBS. However, bloating may also represent small intestinal bacterial overgrowth. Patients with persistent symptoms of abdominal bloating and distension despite dietary interventions should be referred for H₂ breath testing to determine the presence or absence of bacterial overgrowth. If bacterial overgrowth is identified, patients are typically treated with antibiotics. Evaluation of IBS generally includes testing of other disorders that cause similar symptoms. Carbohydrate malabsorption (lactose, fructose, sorbitol) can cause abdominal fullness, bloating, nausea, abdominal pain, flatulence, and diarrhea, which are similar to the symptoms of IBS. However, it is unclear if these digestive disorders contribute to or cause the symptoms of IBS. Research studies show that a proper diagnosis and effective dietary intervention significantly reduces the severity and frequency of gastrointestinal symptoms in IBS. Thus, diagnosis of malabsorption of these carbohydrates in IBS using a breath test is very important to guide the clinician in the proper treatment of IBS patients. PMID:24976698

  2. Air breathing direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming; Gottesfeld, Shimshon

    2002-01-01

    An air breathing direct methanol fuel cell is provided with a membrane electrode assembly, a conductive anode assembly that is permeable to air and directly open to atmospheric air, and a conductive cathode assembly that is permeable to methanol and directly contacting a liquid methanol source. Water loss from the cell is minimized by making the conductive cathode assembly hydrophobic and the conductive anode assembly hydrophilic.

  3. Houses need to breathe--right?

    SciTech Connect

    Sherman, Max H.

    2004-10-01

    Houses need to breathe, but we can no longer leave the important functions associated with ventilation to be met accidentally. A designed ventilation system must be considered as much a part of a home as its heating system. Windows are a key part of that system because they allow a quick increase in ventilation for unusual events, but neither they nor a leaky building shell can be counted on to provide minimum levels.

  4. Breath tests and irritable bowel syndrome

    PubMed Central

    Rana, Satya Vati; Malik, Aastha

    2014-01-01

    Breath tests are non-invasive tests and can detect H2 and CH4 gases which are produced by bacterial fermentation of unabsorbed intestinal carbohydrate and are excreted in the breath. These tests are used in the diagnosis of carbohydrate malabsorption, small intestinal bacterial overgrowth, and for measuring the orocecal transit time. Malabsorption of carbohydrates is a key trigger of irritable bowel syndrome (IBS)-type symptoms such as diarrhea and/or constipation, bloating, excess flatulence, headaches and lack of energy. Abdominal bloating is a common nonspecific symptom which can negatively impact quality of life. It may reflect dietary imbalance, such as excess fiber intake, or may be a manifestation of IBS. However, bloating may also represent small intestinal bacterial overgrowth. Patients with persistent symptoms of abdominal bloating and distension despite dietary interventions should be referred for H2 breath testing to determine the presence or absence of bacterial overgrowth. If bacterial overgrowth is identified, patients are typically treated with antibiotics. Evaluation of IBS generally includes testing of other disorders that cause similar symptoms. Carbohydrate malabsorption (lactose, fructose, sorbitol) can cause abdominal fullness, bloating, nausea, abdominal pain, flatulence, and diarrhea, which are similar to the symptoms of IBS. However, it is unclear if these digestive disorders contribute to or cause the symptoms of IBS. Research studies show that a proper diagnosis and effective dietary intervention significantly reduces the severity and frequency of gastrointestinal symptoms in IBS. Thus, diagnosis of malabsorption of these carbohydrates in IBS using a breath test is very important to guide the clinician in the proper treatment of IBS patients. PMID:24976698

  5. Effect of Mild, Asymptomatic Obstructive Sleep Apnea on Daytime Heart Rate Variability and Impedance Cardiography Measurements

    PubMed Central

    Balachandran, Jay S.; Bakker, Jessie P.; Rahangdale, Shilpa; Yim-Yeh, Susie; Mietus, Joseph E.; Goldberger, Ary L.; Malhotra, Atul

    2011-01-01

    Dysregulation of autonomic nervous system dynamics is important in the pathophysiology of cardiovascular risk in obstructive sleep apnea (OSA). Heart rate variability (HRV) and impedance cardiography measures can estimate autonomic activity but have not gained traction clinically. We hypothesized that, even in a cohort of mild, asymptomatic OSA patients without overt cardiovascular disease, daytime HRV metrics and impedance cardiography measurements of pre-ejection period (PEP) would demonstrate increased sympathetic and decreased parasympathetic modulation compared with matched controls. Obese individuals (BMI ≥30 kg/m2) without any known cardiovascular or inflammatory comorbidities were recruited from the community. Subjects underwent standard in-laboratory polysomnograms (PSG), followed by simultaneous electrocardiography (ECG) and impedance cardiography recordings while supine, supine with paced breathing, and after standing. 74 subjects were studied, and 59% had OSA (apnea-hypopnea index (AHI) ≥10episodes/hr) with a median AHI of 25.8/hr. OSA subjects had significantly decreased daytime time- and frequency-domain HRV indices, but not significantly different PEP, when compared to controls. AHI was a significant independent predictor of time-domain HRV measures in all awake conditions, after controlling for age, gender, blood pressure, fasting cholesterol levels and hemoglobin A1C. In conclusion, our results demonstrate reductions in cardiac vagal modulation, as measured by multiple daytime time-domain markers of HRV, among asymptomatic OSA patients versus controls. Further prospective outcomes-based studies are needed to evaluate the applicability of these metrics for noninvasive screening of obese asymptomatic OSA patients, prior to the onset of overt cardiovascular disease. PMID:21945139

  6. Effect of mild, asymptomatic obstructive sleep apnea on daytime heart rate variability and impedance cardiography measurements.

    PubMed

    Balachandran, Jay S; Bakker, Jessie P; Rahangdale, Shilpa; Yim-Yeh, Susie; Mietus, Joseph E; Goldberger, Ary L; Malhotra, Atul

    2012-01-01

    Dysregulation of autonomic nervous system dynamics is important in the pathophysiology of cardiovascular risk in obstructive sleep apnea (OSA). Heart rate variability (HRV) and impedance cardiography measures can estimate autonomic activity but have not gained traction clinically. The hypothesis of this study was that even in a cohort of patients with mild, asymptomatic OSA without overt cardiovascular disease, daytime HRV metrics and impedance cardiography measurements of preejection period would demonstrate increased sympathetic and decreased parasympathetic modulation compared to matched controls. Obese subjects (body mass index ≥30 kg/m(2)) without any known cardiovascular or inflammatory co-morbidities were recruited from the community. Subjects underwent standard in-laboratory polysomnography followed by simultaneous electrocardiographic and impedance cardiographic recordings while supine, supine with paced breathing, and after standing. Seventy-four subjects were studied, and 59% had OSA (apnea-hypopnea index ≥10 events/hour), with a median apnea-hypopnea index of 25.8 events/hour. Subjects with OSA had significantly decreased daytime time- and frequency-domain HRV indexes, but not significantly different preejection periods, compared to controls. Apnea-hypopnea index was a significant independent predictor of time-domain HRV measures in all awake conditions, after controlling for age, gender, blood pressure, fasting cholesterol levels and glycosylated hemoglobin. In conclusion, these results demonstrate reductions in cardiac vagal modulation, as measured by multiple daytime time-domain markers of HRV, in patients with asymptomatic OSA compared to controls. Further prospective outcomes-based studies are needed to evaluate the applicability of these metrics for noninvasive screening of obese patients with asymptomatic OSA, before the onset of overt cardiovascular disease.

  7. Genetics and early disturbances of breathing control.

    PubMed

    Gaultier, Claude; Amiel, Jeanne; Dauger, Stéphane; Trang, Ha; Lyonnet, Stanislas; Gallego, Jorge; Simonneau, Michel

    2004-05-01

    Early disturbances in breathing control, including apneas of prematurity and apparently life-threatening events, account for some cases of sudden infant death syndrome and for a rare disorder called congenital central hypoventilation syndrome (CCHS). Data suggesting a genetic basis for CCHS have been obtained. Recently, we found heterozygous de novo mutations of the PHOX2B gene in 18 of 29 individuals with CCHS. Most mutations consisted of five to nine alanine expansions within a 20-residue polyalanine tract, probably resulting from nonhomologous recombination. Other mutations, generally inherited from one of the parents, in the coding regions of genes involved in the endothelin and RET signaling pathways and in the brain-derived-neurotrophic factor (BDNF) gene have been found in a few CCHS patients. Interestingly, all these genes are involved in the development of neural crest cells. Targeted disruption of these genes in mice has provided information on the pathophysiological mechanisms underlying CCHS. Despite the identification of these genes involved in breathing control, none of the genetically engineered mice developed to date replicate the full human CCHS respiratory phenotype. Recent insights into the genetic basis for CCHS may shed light on the genetics of other early disturbances in breathing control, such as apnea of prematurity and sudden infant death syndrome. PMID:14739359

  8. The immune response to resistive breathing.

    PubMed

    Vassilakopoulos, T; Roussos, C; Zakynthinos, S

    2004-12-01

    Resistive breathing is an "immune challenge" for the body, initiating an inflammatory response consisting of an elevation of plasma cytokines, and the recruitment and activation of lymphocyte subpopulations. These cytokines do not originate from monocytes, but are, instead, produced within the diaphragm, secondary to the increased muscle activation. Oxidative stress is a major stimulus for the cytokine induction, secondary to resistive breathing. The production of cytokines within the diaphragm may be mediating the diaphragm muscle fibre injury that occurs with strenuous contractions, or contributing towards the expected repair process. These cytokines may also compromise diaphragmatic contractility or contribute towards the development of muscle cachexia. They may also have systemic effects, mobilising glucose from the liver and free fatty acid from the adipose tissue to the strenuously working respiratory muscles. At the same time, they stimulate the hypothalamic-pituitary-adrenal axis, leading to production of adrenocorticotropin and beta-endorphins. The adrenocorticotropin response may represent an attempt of the organism to reduce the injury occurring in the respiratory muscles via the production of glucocorticoids and the induction of the acute phase-response proteins. The beta-endorphin response would decrease the activation of the respiratory muscles and change the pattern of breathing, which becomes more rapid and shallow, possibly in an attempt to reduce and/or prevent further injury to the respiratory muscles. PMID:15572550

  9. Ultrasensitive laser spectroscopy for breath analysis

    NASA Astrophysics Data System (ADS)

    Wojtas, J.; Bielecki, Z.; Stacewicz, T.; Mikołajczyk, J.; Nowakowski, M.

    2012-03-01

    At present there are many reasons for seeking new methods and technologies that aim to develop new and more perfect sensors for different chemical compounds. However, the main reasons are safety ensuring and health care. In the paper, recent advances in the human breath analysis by the use of different techniques are presented. We have selected non-invasive ones ensuring detection of pathogenic changes at a molecular level. The presence of certain molecules in the human breath is used as an indicator of a specific disease. Thus, the analysis of the human breath is very useful for health monitoring. We have shown some examples of diseases' biomarkers and various methods capable of detecting them. Described methods have been divided into non-optical and optical methods. The former ones are the following: gas chromatography, flame ionization detection, mass spectrometry, ion mobility spectrometry, proton transfer reaction mass spectrometry, selected ion flow tube mass spectrometry. In recent twenty years, the optical methods have become more popular, especially the laser techniques. They have a great potential for detection and monitoring of the components in the gas phase. These methods are characterized by high sensitivity and good selectivity. The spectroscopic sensors provide the opportunity to detect specific gases and to measure their concentration either in a sampling place or a remote one. Multipass spectroscopy, cavity ring-down spectroscopy, and photo-acoustic spectroscopy were characterised in the paper as well.

  10. [Model experiments on breathing under sand].

    PubMed

    Maxeiner, H; Haenel, F

    1985-01-01

    Remarkable autopsy findings in persons who had suffocated as a result of closure of the mouth and nose by sand (without the body being buried) induced us to investigate some aspects of this situation by means of a simple experiment. A barrel (diameter 36.7 cm) with a mouthpiece in the bottom was filled with sand to a depth of 15, 30, 60, or 90 cm. The subject tried to breathe as long as possible through the sand, while the amount of sand inspired was measured. Pressure and volume of the breath, as well as the O2 and CO2 content were also measured. A respiratory volume of up to 31 was possible, even when the depth was 90 cm. After about 1 min in all trials, the subject's shortness of breath forced us to stop the experiment. Measurement of O2 and CO2 concentrations proved that respiratory volume in and out of the sand shifts to atmospheric air without gas exchange, even when the sand depth is 15 cm. Sand aspiration depended on the moisture of the material: when the sand was dry, it was impossible to avoid aspiration. However, even a water content of only 5% prevented aspiration, although the sand seemed to be nearly dry.

  11. Commentary on eupneic breathing patterns and gasping.

    PubMed

    Richter, Diethelm W

    2003-12-16

    The term "eupneic activity pattern" is a trivial phenotypical description of a particular activity pattern in respiratory nerves as recorded under in vivo like experimental conditions. This term is, however, inadequate, because Eupnea describes a behavioral breathing performance that is trouble-free occurring without conscious effort. Obviously, the term "eupneic activity pattern" is meant to describe a neural activity that is normal and comparable with quiet breathing conditions. The various in vivo, in situ and in vitro preparations all generate their specific "normal" activity patterns, when the conditions are undisturbed. The commentary describes some of the numerous reasons why such normal activity patterns must be different in the various preparations without indicating their pathological operation. The conclusion is that special considerations are necessary for any extension of the in vitro and in situ findings into in vivo situations, because the capacity of the respiratory network is greatly reduced and thus not comparable with conditions leading to "eupneic breathing" in the fully intact animal.

  12. Analysis of exhaled breath by laser detection

    NASA Astrophysics Data System (ADS)

    Thrall, Karla D.; Toth, James J.; Sharpe, Steven W.

    1996-04-01

    The goal of our work is two fold: (1) to develop a portable rapid laser based breath analyzer for monitoring metabolic processes, and (2) predict these metabolic processes through physiologically based pharmacokinetic (PBPK) modeling. Small infrared active molecules such as ammonia, carbon monoxide, carbon dioxide, methane and ethane are present in exhaled breath and can be readily detected by laser absorption spectroscopy. In addition, many of the stable isotopomers of these molecules can be accurately detected, making it possible to follow specific metabolic processes. Potential areas of applications for this technology include the diagnosis of certain pathologies (e.g. Helicobacter Pylori infection), detection of trauma due to either physical or chemical causes and monitoring nutrient uptake (i.e., malnutrition). In order to understand the origin and elucidate the metabolic processes associated with these small molecules, we are employing physiologically based pharmacokinetic (PBPK) models. A PBPK model is founded on known physiological processes (i.e., blood flow rates, tissue volumes, breathing rate, etc.), chemical-specific processes (i.e., tissue solubility coefficients, molecular weight, chemical density, etc.), and on metabolic processes (tissue site and rate of metabolic biotransformation). Since many of these processes are well understood, a PBPK model can be developed and validated against the more readily available experimental animal data, and then by extrapolating the parameters to apply to man, the model can predict chemical behavior in humans.

  13. Stabilizing immature breathing patterns of preterm infants using stochastic mechanosensory stimulation

    PubMed Central

    Bloch-Salisbury, Elisabeth; Indic, Premananda; Bednarek, Frank

    2009-01-01

    Breathing patterns in preterm infants consist of highly variable interbreath intervals (IBIs) that might originate from nonlinear properties of the respiratory oscillator and its input-output responses to peripheral and central signals. Here, we explore a property of nonlinear control, the potential for large improvement in the stability of breathing using low-level exogenous stochastic stimulation. Stimulation was administered to 10 preterm infants (postconceptional age: mean 33.3 wk, SD 1.7) using a mattress with embedded actuators that delivered small stochastic displacements (0.021 mm root mean square, 0.090 mm maximum, 30–60 Hz); this stimulus was subthreshold for causing arousal from sleep to wakefulness or other detectable changes in the behavioral state evaluated with polysomnography. We used a test-retest protocol with multiple 10-min intervals of stimulation, each paired with 10-min intervals of no stimulation. Stimulation induced an ∼50% reduction (P = 0.003) in the variance of IBIs and an ∼50% reduction (P = 0.002) in the incidence of IBIs > 5 s. The improved stability of eupneic breathing was associated with an ∼65% reduction (P = 0.04) in the duration of O2 desaturation. Our findings suggest that nonlinear properties of the immature respiratory control system can be harnessed using afferent stimuli to stabilize eupneic breathing, thereby potentially reducing the incidence of apnea and hypoxia. PMID:19608934

  14. Nonlinear Steady-State Vibration Analysis of a Beam with Breathing Cracks

    NASA Astrophysics Data System (ADS)

    Kamiya, Keisuke; Yoshinaga, Terumitsu

    This paper presents a method for analysis of steady-state vibration of a beam with breathing cracks, which open and close during vibration. There are several papers treating problems of vibration analysis of a beam with breathing cracks. However, due to their treatments of the condition which determines the switch between the open and closed states of the crack, it is difficult for one to obtain steady-state vibration efficiently by methods such as the incremental harmonic balance method. Since opening and closing of a breathing crack depends on the sign of the bending moment, or the curvature, of the beam, the key point to this problem is explicit treatment of the bending moment. The mixed variational principle allows one to use deflection as well as bending moment as primary variables in the governing equation. In this paper a governing equation of a beam with breathing cracks is derived by a finite element procedure based on the mixed variational principle. Then, the derived governing equations are solved by combining the iteration method and the harmonic balance method. Finally, examples of analysis by the presented method are given.

  15. The Effects of a Suggestive Learning Climate, Synchronized Breathing and Music on the Learning and Retention of Spanish Words

    ERIC Educational Resources Information Center

    Benitez-Bordon, R.; Schuster, Donald H.

    1976-01-01

    This study found that the three variables, suggestion, synchronized music and breathing, had a large positive effect on the learning and retention of 50 Spanish words. Available from: Society for Suggestive-Accelerative Learning and Teaching, 2740 Richmond Avenue, Des Moines, Iowa 50319. (CFM)

  16. Upper extremity kinematics and body roll during preferred-side breathing and breath-holding front crawl swimming.

    PubMed

    Payton, C J; Bartlett, R M; Baltzopoulos, V; Coombs, R

    1999-09-01

    Front crawl swimmers often restrict the number of breaths they take during a race because of the possible adverse effects of the breathing action on resistance or stroke mechanics. The aim of this study was to determine whether differences exist in the kinematics of the trunk and upper extremity used during preferred-side breathing and breath-holding front crawl swimming. Six male swimmers performed trials at their 200 m race pace under breathing and breath-holding conditions. The underwater arm stroke was filmed from the front and side using video cameras suspended over periscope systems. Video recordings were digitized at 50 Hz and the three-dimensional coordinates of the upper extremity obtained using a direct linear transformation algorithm. Body roll angles were obtained by digitizing video recordings of a balsa wood fin attached to the swimmers' backs. The swimmers performed the breathing action without any decrement in stroke length (mean +/- s: breathing 2.24 +/- 0.27 m; breath-holding 2.15 +/- 0.22 m). Stroke widths were similar in the breathing (0.28 +/- 0.07 m) and breath-holding (0.27 +/- 0.07 m) trials, despite swimmers rolling further when taking a breath (66 +/- 5 degrees) than when not (57 +/- 4 degrees). The timing of the four underwater phases of the stroke was also unaffected by the breathing action, with swimmers rolling back towards the neutral position during the insweep phase. In conclusion, the results suggest that front crawl swimmers can perform the breathing action without it interfering with their basic stroke parameters. The insweep phase of the stroke assists body roll and not vice versa as suggested in previous studies.

  17. Determination of breath isoprene allows the identification of the expiratory fraction of the propofol breath signal during real-time propofol breath monitoring.

    PubMed

    Hornuss, Cyrill; Dolch, Michael E; Janitza, Silke; Souza, Kimberly; Praun, Siegfried; Apfel, Christian C; Schelling, Gustav

    2013-10-01

    Real-time measurement of propofol in the breath may be used for routine clinical monitoring. However, this requires unequivocal identification of the expiratory phase of the respiratory propofol signal as only expiratory propofol reflects propofol blood concentrations. Determination of CO2 breath concentrations is the current gold standard for the identification of expiratory gas but usually requires additional equipment. Human breath also contains isoprene, a volatile organic compound with low inspiratory breath concentration and an expiratory concentration plateau. We investigated whether breath isoprene could be used similarly to CO2 to identify the expiratory fraction of the propofol breath signal. We investigated real-time breath data obtained from 40 study subjects during routine anesthesia. Propofol, isoprene, and CO2 breath concentrations were determined by a combined ion molecule reaction/electron impact mass spectrometry system. The expiratory propofol signal was identified according to breath CO2 and isoprene concentrations and presented as median of intervals of 30 s duration. Bland-Altman analysis was applied to detect differences (bias) in the expiratory propofol signal extracted by the two identification methods. We investigated propofol signals in a total of 3,590 observation intervals of 30 s duration in the 40 study subjects. In 51.4 % of the intervals (1,844/3,590) both methods extracted the same results for expiratory propofol signal. Overall bias between the two data extraction methods was -0.12 ppb. The lower and the upper limits of the 95 % CI were -0.69 and 0.45 ppb. Determination of isoprene breath concentrations allows the identification of the expiratory propofol signal during real-time breath monitoring.

  18. DETECTION OF LUNG CANCER USING WEIGHTED DIGITAL ANALYSIS OF BREATH BIOMARKERS

    PubMed Central

    Phillips, Michael; Altorki, Nasser; Austin, John HM; Cameron, Robert B; Cataneo, Renee N; Kloss, Robert; Maxfield, Roger A; Munawar, Muhammad I; Pass, Harvey I; Rashid, Asif; Rom, William N; Schmit, Peter; Wai, James

    2008-01-01

    Background A combination of biomarkers in a multivariate model may predict disease with greater accuracy than a single biomarker employed alone. We developed a non-linear method of multivariate analysis, weighted digital analysis (WDA), and evaluated its ability to predict lung cancer employing volatile biomarkers in the breath. Methods WDA generates a discriminant function to predict membership in disease vs no disease groups by determining weight, a cutoff value, and a sign for each predictor variable employed in the model. The weight of each predictor variable was the area under the curve (AUC) of the receiver operating characteristic (ROC) curve minus a fixed offset of 0.55, where the AUC was obtained by employing that predictor variable alone, as the sole marker of disease. The sign (±) was used to invert the predictor variable if a lower value indicated a higher probability of disease. When employed to predict the presence of a disease in a particular patient, the discriminant function was determined as the sum of the weights of all predictor variables that exceeded their cutoff values. The algorithm that generates the discriminant function is deterministic because parameters are calculated from each individual predictor variable without any optimization or adjustment. We employed WDA to re-evaluate data from a recent study of breath biomarkers of lung cancer, comprising the volatile organic compounds (VOCs) in the alveolar breath of 193 subjects with primary lung cancer and 211 controls with a negative chest CT. Results The WDA discriminant function accurately identified patients with lung cancer in a model employing 30 breath VOCs (ROC curve AUC = 0.90; sensitivity = 84.5%, specificity = 81.0%). These results were superior to multi-linear regression analysis of the same data set (AUC= 0.74, sensitivity = 68.4, specificity = 73.5%). WDA test accuracy did not vary appreciably with TNM (tumor, node, metastasis) stage of disease, and results were not affected

  19. Marathon run: cardiovascular adaptation and cardiovascular risk.

    PubMed

    Predel, Hans-Georg

    2014-11-21

    The first marathon run as an athletic event took place in the context of the Olympic Games in 1896 in Athens, Greece. Today, participation in a 'marathon run' has become a global phenomenon attracting young professional athletes as well as millions of mainly middle-aged amateur athletes worldwide each year. One of the main motives for these amateur marathon runners is the expectation that endurance exercise (EE) delivers profound beneficial health effects. However, with respect to the cardiovascular system, a controversial debate has emerged whether the marathon run itself is healthy or potentially harmful to the cardiovascular system, especially in middle-aged non-elite male amateur runners. In this cohort, exercise-induced increases in cardiac biomarkers-troponin and brain natriuretic peptide-and acute functional cardiac alterations have been observed and interpreted as potential cardiac damage. Furthermore, in the cohort of 40- to 65-year-old males engaged in intensive EE, a significant risk for the development of atrial fibrillation has been identified. Fortunately, recent studies demonstrated a normalization of the cardiac biomarkers and the functional alterations within a short time frame. Therefore, these alterations may be perceived as physiological myocardial reactions to the strenuous exercise and the term 'cardiac fatigue' has been coined. This interpretation is supported by a recent analysis of 10.9 million marathon runners demonstrating that there was no significantly increased overall risk of cardiac arrest during long-distance running races. In conclusion, intensive and long-lasting EE, e.g. running a full-distance Marathon, results in high cardiovascular strain whose clinical relevance especially for middle-aged and older athletes is unclear and remains a matter of controversy. Furthermore, there is a need for evidence-based recommendations with respect to medical screening and training strategies especially in male amateur runners over the age of

  20. Ozone and cardiovascular injury.

    PubMed

    Srebot, Vera; Gianicolo, Emilio A L; Rainaldi, Giuseppe; Trivella, Maria Giovanna; Sicari, Rosa

    2009-06-24

    Air pollution is increasingly recognized as an important and modifiable determinant of cardiovascular diseases in urban communities. The potential detrimental effects are both acute and chronic having a strong impact on morbidity and mortality. The acute exposure to pollutants has been linked to adverse cardiovascular events such as myocardial infarction, heart failure and life-threatening arrhythmias. The long-terms effects are related to the lifetime risk of death from cardiac causes. The WHO estimates that air pollution is responsible for 3 million premature deaths each year. The evidence supporting these data is very strong nonetheless, epidemiologic and observational data have the main limitation of imprecise measurements. Moreover, the lack of clinical experimental models makes it difficult to demonstrate the individual risk. The other limitation is related to the lack of a clear mechanism explaining the effects of pollution on cardiovascular mortality. In the present review we will explore the epidemiological, clinical and experimental evidence of the effects of ozone on cardiovascular diseases. The pathophysiologic consequences of air pollutant exposures have been extensively investigated in pulmonary systems, and it is clear that some of the major components of air pollution (e.g. ozone and particulate matter) can initiate and exacerbate lung disease in humans 1. It is possible that pulmonary oxidant stress mediated by particulate matter and/or ozone (O3) exposure can result in downstream perturbations in the cardiovasculature, as the pulmonary and cardiovascular systems are intricately associated, and it is well documented that specific environmental toxins (such as tobacco smoke 2) introduced through the lungs can initiate and/or accelerate cardiovascular disease development. Indeed, several epidemiologic studies have proved that there is an association between PM and O3 and the increased incidence of cardiovascular morbidity and mortality 3. Most of the

  1. Nutrition and cardiovascular health.

    PubMed

    Berciano, Silvia; Ordovás, José M

    2014-09-01

    A multitude of studies have been published on the relationship between cardiovascular disease risk and a variety of nutrients, foods, and dietary patterns. Despite the well-accepted notion that diet has a significant influence on the development and prevention of cardiovascular disease, the foods considered healthy and harmful have varied over the years. This review aims to summarize the current scientific evidence on the cardioprotective effect of those foods and nutrients that have been considered healthy as well as those that have been deemed unhealthy at any given time in history. For this purpose, we reviewed the most recent literature using as keywords foods and nutrients (ie, meat, omega-3) and cardiovascular disease-related terms (ie, cardiovascular diseases, stroke). Emphasis has been placed on meta-analyses and Cochrane reviews. In general, there is a paucity of intervention studies with a high level of evidence supporting the benefits of healthy foods (ie, fruits and vegetables), whereas the evidence supporting the case against those foods considered less healthy (ie, saturated fat) seems to be weakened by most recent evidence. In summary, most of the evidence supporting the benefits and harms of specific foods and nutrients is based on observational epidemiological studies. The outcome of randomized clinical trials reveals a more confusing picture with most studies providing very small effects in one direction or another; the strongest evidence comes from dietary patterns. The current status of the relationship between diet and cardiovascular disease risk calls for more tailored recommendations based on genomic technologies.

  2. Cardiovascular disease mortality.

    PubMed

    Onwuanyi, Anekwe E; Clarke, Aubrey; Vanderbush, Eric

    2003-12-01

    Although mortality from cardiovascular diseases (CVDs) has been declining, it remains the leading cause of death among urban U.S. blacks. McCord and Freeman reported CVD as the major contributor to excess mortality in Central Harlem. However the disease-specific CVD mortality was not assessed. Thus, it was unclear what the distribution of specific CVDs was in Central Harlem and their contribution to excess mortality. We reviewed the vital statistics records of New York City (NYC) Department of Health for 1990 and identified all cases in which the cause of death was coded as cardiovascular (International Classification of Diseases-ICD, 9th Revision, codes 391, 393-398, 401-404, 410, 411, 414-417, 420-438 and 440-444). The total and disease-specific CVD mortality for NYC and Central Harlem were calculated using the appropriate 1990 census data as the denominator. Central Harlem residents aged between 25-64 years were at least twice as likely to die from cardiovascular causes, compared to NYC residents. Hypertension-related deaths, ICD codes 401 (essential hypertension), 402 (hypertensive heart disease), 403 (hypertensive renal disease), and 404 (hypertensive heart and renal disease), were the major cause of excess death for men and women in Central Harlem. These findings show the importance of hypertension as the main determinant of the excess cardiovascular mortality in urban blacks and suggest an increased risk of cardiovascular death in blacks residing in Central Harlem.

  3. Cardiovascular function in acromegaly.

    PubMed

    Clayton, R N

    2003-06-01

    Even with modern treatment, acromegaly is associated with a 2- to 3-fold increase in mortality, mainly from vascular disease, which is probably a result of the long exposure of tissues to excess GH before diagnosis and treatment. There is accumulating evidence that effective treatment to lower serum GH levels to less than 1-2 ng/ml (glucose suppressed or random, respectively) and normalize IGF-I improves long-term outcome and survival. In addition to recognized cardiovascular risk factors of hypertension, type 2 diabetes mellitus, and dyslipidemia, there is accumulating evidence of specific structural and functional changes in the heart in acromegaly. Along with endothelial dysfunction, these changes may contribute to the increased mortality in this disease. There are specific structural changes in the myocardium with increased myocyte size and interstitial fibrosis of both ventricles. Left ventricular hypertrophy is common even in young patients with short duration of disease. Some of these structural changes can be reversed by effective treatment. Functionally, the main consequence of these changes is impaired left ventricular diastolic function, particularly when exercising, such that exercise tolerance is reduced. Diastolic function improves with treatment, but the effect on exercise tolerance is more variable, and more longitudinal data are required to assess the benefits. What scant data there are on rhythm changes suggest an increase in complex ventricular arrhythmias, possibly as a result of the disordered left ventricular architecture. The functional consequences of these changes are unclear, but they may provide a useful early marker for the ventricular remodeling that occurs in the acromegalic heart. Endothelial dysfunction, especially flow-mediated dilatation, is an early marker of atherosclerosis, and limited data imply that this is impaired in active acromegaly and can be improved with treatment. Similarly, early arterial structural changes, such as

  4. Psychophysiological effects of breathing instructions for stress management.

    PubMed

    Conrad, Ansgar; Müller, Anett; Doberenz, Sigrun; Kim, Sunyoung; Meuret, Alicia E; Wollburg, Eileen; Roth, Walton T

    2007-06-01

    Stressed and tense individuals often are recommended to change the way they breathe. However, psychophysiological effects of breathing instructions on respiration are rarely measured. We tested the immediate effects of short and simple breathing instructions in 13 people seeking treatment for panic disorder, 15 people complaining of daily tension, and 15 controls. Participants underwent a 3-hour laboratory session during which instructions to direct attention to breathing and anti-hyperventilation instructions to breathe more slowly, shallowly, or both were given. Respiratory, cardiac, and electrodermal measures were recorded. The anti-hyperventilation instructions failed to raise end-tidal pCO(2) above initial baseline levels for any of the groups because changes in respiratory rate were compensated for by changes in tidal volume and vice versa. Paying attention to breathing significantly reduced respiratory rate and decreased tidal volume instability compared to the other instructions. Shallow breathing made all groups more anxious than did other instructions. Heart rate and skin conductance were not differentially affected by instructions. We conclude that simple and short instructions to alter breathing do not change respiratory or autonomic measures in the direction of relaxation, except for attention to breathing, which increases respiratory stability. To understand the results of breathing instructions for stress and anxiety management, respiration needs to be monitored physiologically.

  5. Diabetes Drugs and Cardiovascular Safety

    PubMed Central

    2016-01-01

    Diabetes is a well-known risk factor of cardiovascular morbidity and mortality, and the beneficial effect of improved glycemic control on cardiovascular complications has been well established. However, the rosiglitazone experience aroused awareness of potential cardiovascular risk associated with diabetes drugs and prompted the U.S. Food and Drug Administration to issue new guidelines about cardiovascular risk. Through postmarketing cardiovascular safety trials, some drugs demonstrated cardiovascular benefits, while some antidiabetic drugs raised concern about a possible increased cardiovascular risk associated with drug use. With the development of new classes of drugs, treatment options became wider and the complexity of glycemic management in type 2 diabetes has increased. When choosing the appropriate treatment strategy for patients with type 2 diabetes at high cardiovascular risk, not only the glucose-lowering effects, but also overall benefits and risks for cardiovascular disease should be taken into consideration. PMID:27302713

  6. Tea and Cardiovascular Disease

    PubMed Central

    Deka, Apranta; Vita, Joseph A.

    2011-01-01

    There is increasing evidence for a protective effect of tea consumption against cardiovascular disease. This review summarizes the available epidemiological data providing evidence for and against such an effect. We also review observational and intervention studies that investigated an effect of tea and tea extracts on cardiovascular risk factors, including blood pressure, serum lipids, diabetes mellitus, and obesity. Finally, we review potential mechanisms of benefit, including anti-inflammatory, anti-oxidant, and anti-proliferative effects, as well as favorable effects on endothelial function. Overall, the observational data suggest a benefit, but results are mixed and likely confounded by lifestyle and background dietary factors. The weight of evidence indicates favorable effects on risk factors and a number of plausible mechanisms have been elucidated in experimental and translational human studies. Despite the growing body evidence, it remains uncertain whether tea consumption should be recommended to the general population or to patients as a strategy to reduce cardiovascular risk. PMID:21477653

  7. Cardiovascular disease prevention.

    PubMed

    Van Camp, G

    2014-12-01

    Cardiovascular diseases remain the first killer in the Western countries. Equivalent contributions of prevention initiatives, pharmaceutical developments and technological improvements have led to an important success in the reduction of mortality related to cardiovascular diseases in some of the countries of the Western world. However, increase in life expectance, incomplete adherence to guidelines, difficulties in convincing governments and the population to support and adhere to prevention measures make that the burden of cardiovascular diseases is still extremely high. This review gives a restricted summary of the most important prevention guidelines supported by the European Society of Cardiology. It also illustrates the still very incomplete adherence to these guidelines in the different European countries as published in the EUROASPIRE surveys.

  8. Mitochondria and Cardiovascular Aging

    PubMed Central

    Dai, Dao-Fu; Ungvari, Zoltan

    2013-01-01

    Old age is a major risk factor for cardiovascular diseases. Several lines of evidence in experimental animal models have indicated the central role of mitochondria both in lifespan determination and cardiovascular aging. In this article we review the evidence supporting the role of mitochondrial oxidative stress, mitochondrial damage and biogenesis as well as the crosstalk between mitochondria and cellular signaling in cardiac and vascular aging. Intrinsic cardiac aging in the murine model closely recapitulates age-related cardiac changes in humans (left ventricular hypertrophy, fibrosis and diastolic dysfunction), while the phenotype of vascular aging include endothelial dysfunction, reduced vascular elasticity and chronic vascular inflammation. Both cardiac and vascular aging involve neurohormonal signaling (e.g. renin-angiotensin, adrenergic, insulin-IGF1 signaling) and cell-autonomous mechanisms. The potential therapeutic strategies to improve mitochondrial function in aging and cardiovascular diseases are also discussed, with a focus on mitochondrial-targeted antioxidants, calorie restriction, calorie restriction mimetics and exercise training. PMID:22499901

  9. Nonlinear dynamics of cardiovascular ageing

    PubMed Central

    Shiogai, Y.; Stefanovska, A.; McClintock, P.V.E.

    2010-01-01

    The application of methods drawn from nonlinear and stochastic dynamics to the analysis of cardiovascular time series is reviewed, with particular reference to the identification of changes associated with ageing. The natural variability of the heart rate (HRV) is considered in detail, including the respiratory sinus arrhythmia (RSA) corresponding to modulation of the instantaneous cardiac frequency by the rhythm of respiration. HRV has been intensively studied using traditional spectral analyses, e.g. by Fourier transform or autoregressive methods, and, because of its complexity, has been used as a paradigm for testing several proposed new methods of complexity analysis. These methods are reviewed. The application of time–frequency methods to HRV is considered, including in particular the wavelet transform which can resolve the time-dependent spectral content of HRV. Attention is focused on the cardio-respiratory interaction by introduction of the respiratory frequency variability signal (RFV), which can be acquired simultaneously with HRV by use of a respiratory effort transducer. Current methods for the analysis of interacting oscillators are reviewed and applied to cardio-respiratory data, including those for the quantification of synchronization and direction of coupling. These reveal the effect of ageing on the cardio-respiratory interaction through changes in the mutual modulation of the instantaneous cardiac and respiratory frequencies. Analyses of blood flow signals recorded with laser Doppler flowmetry are reviewed and related to the current understanding of how endothelial-dependent oscillations evolve with age: the inner lining of the vessels (the endothelium) is shown to be of crucial importance to the emerging picture. It is concluded that analyses of the complex and nonlinear dynamics of the cardiovascular system can illuminate the mechanisms of blood circulation, and that the heart, the lungs and the vascular system function as a single entity in

  10. Is meditation always relaxing? Investigating heart rate, heart rate variability, experienced effort and likeability during training of three types of meditation.

    PubMed

    Lumma, Anna-Lena; Kok, Bethany E; Singer, Tania

    2015-07-01

    Meditation is often associated with a relaxed state of the body. However, meditation can also be regarded as a type of mental task and training, associated with mental effort and physiological arousal. The cardiovascular effects of meditation may vary depending on the type of meditation, degree of mental effort, and amount of training. In the current study we assessed heart rate (HR), high-frequency heart rate variability (HF-HRV) and subjective ratings of effort and likeability during three types of meditation varying in their cognitive and attentional requirements, namely breathing meditation, loving-kindness meditation and observing-thoughts meditation. In the context of the ReSource project, a one-year longitudinal mental training study, participants practiced each meditation exercise on a daily basis for 3 months. As expected HR and effort were higher during loving-kindness meditation and observing-thoughts meditation compared to breathing meditation. With training over time HR and likeability increased, while HF-HRV and the subjective experience of effort decreased. The increase in HR and decrease in HF-HRV over training was higher for loving-kindness meditation and observing-thoughts meditation compared to breathing meditation. In contrast to implicit beliefs that meditation is always relaxing and associated with low arousal, the current results show that core meditations aiming at improving compassion and meta-cognitive skills require effort and are associated with physiological arousal compared to breathing meditation. Overall these findings can be useful in making more specific suggestions about which type of meditation is most adaptive for a given context and population. PMID:25937346

  11. Is meditation always relaxing? Investigating heart rate, heart rate variability, experienced effort and likeability during training of three types of meditation.

    PubMed

    Lumma, Anna-Lena; Kok, Bethany E; Singer, Tania

    2015-07-01

    Meditation is often associated with a relaxed state of the body. However, meditation can also be regarded as a type of mental task and training, associated with mental effort and physiological arousal. The cardiovascular effects of meditation may vary depending on the type of meditation, degree of mental effort, and amount of training. In the current study we assessed heart rate (HR), high-frequency heart rate variability (HF-HRV) and subjective ratings of effort and likeability during three types of meditation varying in their cognitive and attentional requirements, namely breathing meditation, loving-kindness meditation and observing-thoughts meditation. In the context of the ReSource project, a one-year longitudinal mental training study, participants practiced each meditation exercise on a daily basis for 3 months. As expected HR and effort were higher during loving-kindness meditation and observing-thoughts meditation compared to breathing meditation. With training over time HR and likeability increased, while HF-HRV and the subjective experience of effort decreased. The increase in HR and decrease in HF-HRV over training was higher for loving-kindness meditation and observing-thoughts meditation compared to breathing meditation. In contrast to implicit beliefs that meditation is always relaxing and associated with low arousal, the current results show that core meditations aiming at improving compassion and meta-cognitive skills require effort and are associated with physiological arousal compared to breathing meditation. Overall these findings can be useful in making more specific suggestions about which type of meditation is most adaptive for a given context and population.

  12. [Conditioning of affect-induced breath-holding spells].

    PubMed

    Noeker, M; Haverkamp, F

    1997-01-01

    Breath holding spells often arise in the context of affectively dramatic conflict situations between mother and child. Assessment by psychopathological screening instruments, however, has not given empirical evidence of an increased psychiatric morbidity in these children. Therefore, in our study we did not concentrate on basic psychopathology but on behavioral variables that might be effective during the ongoing attack episode and, hereby, exert an influence on the risk of chronification (relapse rate). The main goal of this approach is to examine secondary reinforcement effects on the attack behavior according to the learning principle of operant conditioning. Our sample consisted of 28 children and ten siblings as control group. To control for effects of behavioral disorders in the sample, we applied the Marburger Verhaltensliste (MVL) on the level of the child, and the Familienfragebogen (FFBO-III) on the level of family adaptation. The main assessment instrument, however, was the Functional Behavior Analysis (FBA) in order to measure the trigger, reaction and consequence conditions in the course of given attack episodes. MVL and FFBO-III results confirm the lack of basic psychopathology in the patients and their families. The individualized FBA's can be transformed in a taxonomy of five distinct types. All the first three types are triggered by intensive conflict situations and show a high relapse rate (type 1) if the mother reacts in a rewarding manner with positive consequences for the child (reinforcement condition), a dramatically reduced rate (type 2) if the mother reacts neutral (extinction condition), or a heterogeneous pattern (type 3) if the mother reacts punishing (punishment condition). In type 4 (pallid type) and type 5 (triggered spontaneously), respectively, no responsiveness to conditioning effects can be recognized. With respect to parent counselling, a recommendation for a quiet and consequent reaction can be concluded, especially in the case

  13. Evaluation of tracheal cuff pressure variation in spontaneously breathing patients

    PubMed Central

    Plotnikow, Gustavo A; Roux, Nicolas; Feld, Viviana; Gogniat, Emiliano; Villalba, Dario; Ribero, Noelia Vairo; Sartore, Marisa; Bosso, Mauro; Quiroga, Corina; Leiva, Valeria; Scrigna, Mariana; Puchulu, Facundo; Distéfano, Eduardo; Scapellato, Jose Luis; Intile, Dante; Planells, Fernando; Noval, Diego; Buñirigo, Pablo; Jofré, Ricardo; Nielsen, Ernesto Díaz

    2013-01-01

    Background: Most of the studies referring cuff tubes’ issues were conducted on intubated patients. Not much is known about the cuff pressure performance in chronically tracheostomized patients disconnected from mechanical ventilation. Objective: To evaluate cuff pressure (CP) variation in tracheostomized, spontaneously breathing patients in a weaning rehabilitation center. Materials and Methods: Experimental setup to test instruments in vitro, in which the gauge (TRACOE) performance at different pressure levels was evaluated in six tracheostomy tubes, and a clinical setupin which CP variation over 24 h, every 4 h, and for 6 days was measured in 35 chronically tracheostomized clinically stable, patients who had been disconnected from mechanical ventilation for at least 72 h. The following data were recorded: Tube brand, type, and size; date of the tube placed; the patient's body position; the position of the head; axillary temperature; pulse and respiration rates; blood pressure; and pulse oximetry. Results: In vitro difference between the initial pressure (IP) and measured pressure (MP) was statistically significant (P < 0.05). The difference between the IP and MP was significant when selecting for various tube brands (P < 0.05). In the clinical set-up, 207 measurements were performed and the CP was >30 cm H2O in 6.28% of the recordings, 20-30 cm H2O in 42.0% of the recordings, and <20 cm H2O in 51.69% of the recordings. Conclusion: The systematic CP measurement in chronically tracheostomized, spontaneously breathing patients showed high variability, which was independent of tube brand, size, type, or time of placement. Consequently, measurements should be made more frequently. PMID:24459624

  14. Artificial neural networks to model and diagnose cardiovascular systems

    SciTech Connect

    Kangas, L.J.; Keller, P.E.; Allen, P.A.

    1995-12-31

    In this paper, a novel approach to modeling and diagnosing the cardiovascular system is introduced. A model exhibits a subset of the dynamics of the cardiovascular behavior of an individual by using a recurrent artificial neural network. Potentially, a model will be incorporated into a cardiovascular diagnostic system. This approach is unique in that each cardiovascular model is developed from physiological measurements of an individual. Any differences between the modeled variables and. the actual variables of an individual at a given time are used for diagnosis. This approach also exploits sensor fusion to optimize the utilization of biomedical sensors. The advantage of sensor fusion has been demonstrated in applications including control and diagnostics of mechanical and chemical processes.

  15. A novel approach to modeling and diagnosing the cardiovascular system

    SciTech Connect

    Keller, P.E.; Kangas, L.J.; Hashem, S.; Kouzes, R.T.; Allen, P.A.

    1995-07-01

    A novel approach to modeling and diagnosing the cardiovascular system is introduced. A model exhibits a subset of the dynamics of the cardiovascular behavior of an individual by using a recurrent artificial neural network. Potentially, a model will be incorporated into a cardiovascular diagnostic system. This approach is unique in that each cardiovascular model is developed from physiological measurements of an individual. Any differences between the modeled variables and the variables of an individual at a given time are used for diagnosis. This approach also exploits sensor fusion to optimize the utilization of biomedical sensors. The advantage of sensor fusion has been demonstrated in applications including control and diagnostics of mechanical and chemical processes.

  16. Cardiovascular Disease and Menopause

    PubMed Central

    Dosi, Rupal; Bhatt, Nikita; Shah, Priyanki; Patell, Rushad

    2014-01-01

    Aim: The aim of the study was to study the abnormalities in the cardiovascular profile in postmenopausal Indian women and to compare the same with the cardiovascular profile of pre menopausal Indian women belonging to the same age group; taken as controls. The goal was to throw some light on the cardiovascular risk in postmenopausal women of the Indian population as this population is thought to be at higher risk than their western counterparts and significant studies of the same kind in this population have been few. Materials and Methods: A cross-sectional comparative study on 100 women who were either postmenopausal or premenopausal and were between the age group of 40 to 55 years was carried out over a period of ten months at our hospital. The variations in the cardiovascular profile between both groups were studied. All the women were subjected to a detailed history, thorough examination, investigations and imaging studies. Results: The evaluation revealed that Coronary Artery Disease (CAD), hypertension, abnormal Body Mass Index (BMI) and abnormal Waist Hip Ratio (WHR) were significantly higher in the postmenopausal group as compared to the premenopausal group. The post menopausal women had significantly higher prevalence of abnormal lipid profiles as compared to their premenopausal counterparts. The postmenopausal women with a normal lipid profile also had increased prevalence of CAD and SAHT, which emphasizes the non-lipid cardiovascular benefits of estrogen. Conclusion: Thus, we can conclude that cardiovascular disease was more common in postmenopausal women of age group 40-55 years as compared to those not yet achieved menopause in a population of western Indian women. And this risk was significantly associated with central obesity, an abnormal lipid profile and the postmenopausal state in itself. PMID:24701484

  17. Ventilatory efficiency and breathing pattern in world-class cyclists: A three-year observational study.

    PubMed

    Salazar-Martínez, Eduardo; Terrados, Nicolás; Burtscher, Martin; Santalla, Alfredo; Naranjo Orellana, José

    2016-07-15

    The purpose of this three-year observational study was to analyze the ventilatory efficiency and breathing pattern in world-class professional cyclists. Twelve athletes (22.61±3.8years; 177.38±5.5cm; 68.96±5.5kg and VO2max 75.51±3.3mLkg(-1)min(-1)) were analyzed retrospectively. For each subject, respiratory and performance variables were recorded during incremental spiroergometry: oxygen uptake (VO2), carbon dioxide output (VCO2), pulmonary ventilation (VE), tidal volume (Vt), breathing frequency (fR), driving (Vt/Ti), timing (Ti/Ttot), peak power output (PPO) and maximum oxygen uptake (VO2max). Ventilatory efficiency (VE/VCO2 slope) was calculated from the beginning of exercise testing to the second ventilatory threshold (VT2). The VE/VCO2 slope was unaffected during the study period (24.63±3.07; 23.61±2:79; 24:89±2:61) with a low effect size (ES=0.04). The PPO improved significantly in the third year (365±33.74; 386.36±32.33; 415.00±24.15) (p<0.05). The breathing pattern variables, Vt/Ti and Ti/Ttot, did not change significantly over the three year period (ES=0.00; ES=0.03 respectively). These findings suggest that changes in cycling performance in world-class professional cyclists do not modify breathing variables related to the control of ventilatory efficiency.

  18. Ventilatory efficiency and breathing pattern in world-class cyclists: A three-year observational study.

    PubMed

    Salazar-Martínez, Eduardo; Terrados, Nicolás; Burtscher, Martin; Santalla, Alfredo; Naranjo Orellana, José

    2016-07-15

    The purpose of this three-year observational study was to analyze the ventilatory efficiency and breathing pattern in world-class professional cyclists. Twelve athletes (22.61±3.8years; 177.38±5.5cm; 68.96±5.5kg and VO2max 75.51±3.3mLkg(-1)min(-1)) were analyzed retrospectively. For each subject, respiratory and performance variables were recorded during incremental spiroergometry: oxygen uptake (VO2), carbon dioxide output (VCO2), pulmonary ventilation (VE), tidal volume (Vt), breathing frequency (fR), driving (Vt/Ti), timing (Ti/Ttot), peak power output (PPO) and maximum oxygen uptake (VO2max). Ventilatory efficiency (VE/VCO2 slope) was calculated from the beginning of exercise testing to the second ventilatory threshold (VT2). The VE/VCO2 slope was unaffected during the study period (24.63±3.07; 23.61±2:79; 24:89±2:61) with a low effect size (ES=0.04). The PPO improved significantly in the third year (365±33.74; 386.36±32.33; 415.00±24.15) (p<0.05). The breathing pattern variables, Vt/Ti and Ti/Ttot, did not change significantly over the three year period (ES=0.00; ES=0.03 respectively). These findings suggest that changes in cycling performance in world-class professional cyclists do not modify breathing variables related to the control of ventilatory efficiency. PMID:27083403

  19. Progression of cardiovascular autonomic dysfunction in Holmes-Adie syndrome.

    PubMed

    Guaraldi, P; Mathias, C J

    2011-09-01

    The Holmes-Adie Syndrome (HAS) is a disorder of unknown aetiology comprising unilateral or bilateral tonic pupils with near light dissociation and tendon areflexia. Although considered to be benign, troublesome symptoms may result from autonomic disturbances, affecting vasomotor, sudomotor and respiratory function. It is unclear if the autonomic manifestations of the disease remain stable or progress, as longitudinal studies with detailed autonomic assessments have not been described. The authors report four HAS patients studied at intervals over 16, 8, 4 and 2 years with cardiovascular autonomic tests (head-up tilt, isometric exercise, mental arithmetic, cutaneous cold, deep breathing, Valsalva manoeuvre and standing). In each, there was progression of cardiovascular autonomic deficits with time, accompanied by symptomatic worsening. These observations in HAS, for the first time, indicate progression of cardiovascular autonomic dysfunction of clinical significance. This has a number of implications, including those relating to aetiology and prognosis. The authors recommend regular clinical and laboratory follow-up, especially of cardiovascular autonomic function, in patients with HAS.

  20. Advancing cardiovascular tissue engineering

    PubMed Central

    Truskey, George A.

    2016-01-01

    Cardiovascular tissue engineering offers the promise of biologically based repair of injured and damaged blood vessels, valves, and cardiac tissue. Major advances in cardiovascular tissue engineering over the past few years involve improved methods to promote the establishment and differentiation of induced pluripotent stem cells (iPSCs), scaffolds from decellularized tissue that may produce more highly differentiated tissues and advance clinical translation, improved methods to promote vascularization, and novel in vitro microphysiological systems to model normal and diseased tissue function. iPSC technology holds great promise, but robust methods are needed to further promote differentiation. Differentiation can be further enhanced with chemical, electrical, or mechanical stimuli. PMID:27303643