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Sample records for breathing cardiovascular variability

  1. 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

  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.

  3. 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.

  4. 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.

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

    PubMed Central

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

    2014-01-01

    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. PMID:25063789

  6. 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.

  7. Heart rate variability with deep breathing as a clinical test of cardiovagal function.

    PubMed

    Shields, Robert W

    2009-04-01

    Research into heart rate variability (HRV) and respiration over the past 150 years has led to the insight that HRV with deep breathing (HRVdb) is a highly sensitive measure of cardiovagal or parasympathetic cardiac function. This sensitivity makes HRVdb an important part of the battery of cardiovascular autonomic function tests used in clinical autonomic laboratories. HRVdb is a reliable and sensitive clinical test for early detection of cardiovagal dysfunction in a wide range of autonomic disorders.

  8. 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.

  9. 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

  10. [Variability of breathing pattern during inspiratory elastic load].

    PubMed

    D'Negri, Carlos E; Pessolano, Fernando A; De Vito, Eduardo L

    2009-01-01

    In humans, lung ventilation exhibits breath-to-breath variability and dynamics that are nonlinear, complex and chaotic. Our objective was to characterize the breathing pattern variational activity in anesthetized dogs (n: 8) breathing through threshold inspiratory elastic load (7 to 50 cm H2O). Starting from flow signal and tracheal and esophageal pressures, we analyzed inspiratory time (Ti), timing (expiratory time, Te; total time, Ttot; and Ti/Ttot) and central drive (Vt/Ti) and variables related to it (tidal volume, Vt and pulmonary ventilation, Ve). We measured gross variability (variances), low frequency oscillations (spectral analysis), and short term memory (autocorrelation analysis). Loading decreased variance of the mean values of Te, Ttot, Vt and Vt/Ti (p < 0.05); the mean of variances for Ti/Ttot increased (p < 0.005) while it decreased for Vt and Vt/Ti (p < 0.05). In general, percent of data recordings with low frequency oscillations (OB%) decreased (p < 0.02). During heavy load, timing parameters percent of data recordings with autocorrelations (AU%) did not change, but Vt and its related parameters decreased their AU% (p < 0.005). There was a positive correlation (r: 0.955, p < 0.001) between the existence of low frequency oscillations and autocorrelations for Vt and its related parameters, while timing variables did not show such a correlation. In conclusion, threshold elastic load induced a monotonous respiratory pattern. The short term memory decreased during inspiratory stage while increased during expiratory stage. These changes occurred during anesthesia suggesting that certain suprapontine structures may not be obligatory to induce them.

  11. 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.

  12. 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.

  13. An integrative model of respiratory and cardiovascular control in sleep-disordered breathing

    PubMed Central

    Cheng, Limei; Ivanova, Olga; Fan, Hsing-Hua; Khoo, Michael C. K.

    2010-01-01

    While many physiological control models exist in the literature, none thus far has focused on characterizing the interactions among the respiratory, cardiovascular and sleep-wake regulation systems that occur in sleep-disordered breathing. The model introduced in this study integrates the autonomic control of the cardiovascular system, chemoreflex and state-related control of respiration, including respiratory and upper airway mechanics, along with a model of circadian and sleep-wake regulation. The integrative model provides realistic predictions of the physiological responses under a variety of conditions including: the sleep-wake cycle, hypoxia-induced periodic breathing, Cheyne-Stokes respiration in chronic heart failure, and obstructive sleep apnoea (OSA). It can be used to investigate the effects of a variety of interventions, such as isocapnic and hypercapnic and/or hypoxic gas administration, the Valsalva and Mueller maneuvers, and the application of continuous positive airway pressure on OSA subjects. By being able to delineate the influences of the various interacting physiological mechanisms, the model is useful in providing a more lucid understanding of the complex dynamics that characterize state-cardiorespiratory control in the different forms of sleep-disordered breathing. PMID:20542148

  14. Low-frequency heart rate variability is related to the breath-to-breath variability in the respiratory pattern.

    PubMed

    Beda, Alessandro; Simpson, David M; Carvalho, Nadja C; Carvalho, Alysson Roncally S

    2014-02-01

    Changes in heart rate variability (HRV) at "respiratory" frequencies (0.15-0.5 Hz) may result from changes in respiration rather than autonomic control. We now investigate if the differences in HRV power in the low-frequency (LF) band (0.05-0.15 Hz, HRV(LF)) can also be predicted by respiration variability, quantified by the fraction of tidal volume power in the LF (V(LF,n)). Three experimental protocols were considered: paced breathing, mental effort tasks, and a repeated attentional task. Significant intra- and interindividual correlations were found between changes in HRV(LF) and V(LF,n) despite all subjects having a respiratory frequency above the LF band. Respiratory parameters (respiratory period, tidal volume, and V(LF,n)) could predict up to 79% of HRV(LF) differences in some cases. This suggests that respiratory variability is another mechanism of HRV(LF) generation, which should be always monitored, assessed, and considered in the interpretation of HRV changes.

  15. 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.

  16. Phase Synchronization of Hemodynamic Variables at Rest and after Deep Breathing Measured during the Course of Pregnancy

    PubMed Central

    Papousek, Ilona; Roessler, Andreas; Hinghofer-Szalkay, Helmut; Lang, Uwe; Kolovetsiou-Kreiner, Vassiliki

    2013-01-01

    Background The autonomic nervous system plays a central role in the functioning of systems critical for the homeostasis maintenance. However, its role in the cardiovascular adaptation to pregnancy-related demands is poorly understood. We explored the maternal cardiovascular systems throughout pregnancy to quantify pregnancy-related autonomic nervous system adaptations. Methodology Continuous monitoring of heart rate (R-R interval; derived from the 3-lead electrocardiography), blood pressure, and thoracic impedance was carried out in thirty-six women at six time-points throughout pregnancy. In order to quantify in addition to the longitudinal effects on baseline levels throughout gestation the immediate adaptive heart rate and blood pressure changes at each time point, a simple reflex test, deep breathing, was applied. Consequently, heart rate variability and blood pressure variability in the low (LF) and high (HF) frequency range, respiration and baroreceptor sensitivity were analyzed in resting conditions and after deep breathing. The adjustment of the rhythms of the R-R interval, blood pressure and respiration partitioned for the sympathetic and the parasympathetic branch of the autonomic nervous system were quantified by the phase synchronization index γ, which has been adopted from the analysis of weakly coupled chaotic oscillators. Results Heart rate and LF/HF ratio increased throughout pregnancy and these effects were accompanied by a continuous loss of baroreceptor sensitivity. The increases in heart rate and LF/HF ratio levels were associated with an increasing decline in the ability to flexibly respond to additional demands (i.e., diminished adaptive responses to deep breathing). The phase synchronization index γ showed that the observed effects could be explained by a decreased coupling of respiration and the cardiovascular system (HF components of heart rate and blood pressure). Conclusions/Significance The findings suggest that during the course of

  17. Heart rate variability and muscle sympathetic nerve activity response to acute stress: the effect of breathing

    PubMed Central

    DeBeck, Lindsay D.; Petersen, Stewart R.; Jones, Kelvin E.; Stickland, Michael K.

    2016-01-01

    Previous research has suggested a relationship between low-frequency power of heart rate variability (HRV; LF in normalized units, LFnu) and muscle sympathetic nerve activity (MSNA). However, investigations have not systematically controlled for breathing, which can modulate both HRV and MSNA. Accordingly, the aims of this experiment were to investigate the possibility of parallel responses in MSNA and HRV (LFnu) to selected acute stressors and the effect of controlled breathing. After data were obtained at rest, 12 healthy males (28 ± 5 yr) performed isometric handgrip exercise (30% maximal voluntary contraction) and the cold pressor test in random order, and were then exposed to hypoxia (inspired fraction of O2 = 0.105) for 7 min, during randomly assigned spontaneous and controlled breathing conditions (20 breaths/min, constant tidal volume, isocapnic). MSNA was recorded from the peroneal nerve, whereas HRV was calculated from ECG. At rest, controlled breathing did not alter MSNA but decreased LFnu (P < 0.05 for all) relative to spontaneous breathing. MSNA increased in response to all stressors regardless of breathing. LFnu increased with exercise during both breathing conditions. During cold pressor, LFnu decreased when breathing was spontaneous, whereas in the controlled breathing condition, LFnu was unchanged from baseline. Hypoxia elicited increases in LFnu when breathing was controlled, but not during spontaneous breathing. The parallel changes observed during exercise and controlled breathing during hypoxia suggest that LFnu may be an indication of sympathetic outflow in select conditions. However, since MSNA and LFnu did not change in parallel with all stressors, a cautious approach to the use of LFnu as a marker of sympathetic activity is warranted. PMID:20410469

  18. Heart rate variability and muscle sympathetic nerve activity response to acute stress: the effect of breathing.

    PubMed

    DeBeck, Lindsay D; Petersen, Stewart R; Jones, Kelvin E; Stickland, Michael K

    2010-07-01

    Previous research has suggested a relationship between low-frequency power of heart rate variability (HRV; LF in normalized units, LFnu) and muscle sympathetic nerve activity (MSNA). However, investigations have not systematically controlled for breathing, which can modulate both HRV and MSNA. Accordingly, the aims of this experiment were to investigate the possibility of parallel responses in MSNA and HRV (LFnu) to selected acute stressors and the effect of controlled breathing. After data were obtained at rest, 12 healthy males (28 +/- 5 yr) performed isometric handgrip exercise (30% maximal voluntary contraction) and the cold pressor test in random order, and were then exposed to hypoxia (inspired fraction of O(2) = 0.105) for 7 min, during randomly assigned spontaneous and controlled breathing conditions (20 breaths/min, constant tidal volume, isocapnic). MSNA was recorded from the peroneal nerve, whereas HRV was calculated from ECG. At rest, controlled breathing did not alter MSNA but decreased LFnu (P < 0.05 for all) relative to spontaneous breathing. MSNA increased in response to all stressors regardless of breathing. LFnu increased with exercise during both breathing conditions. During cold pressor, LFnu decreased when breathing was spontaneous, whereas in the controlled breathing condition, LFnu was unchanged from baseline. Hypoxia elicited increases in LFnu when breathing was controlled, but not during spontaneous breathing. The parallel changes observed during exercise and controlled breathing during hypoxia suggest that LFnu may be an indication of sympathetic outflow in select conditions. However, since MSNA and LFnu did not change in parallel with all stressors, a cautious approach to the use of LFnu as a marker of sympathetic activity is warranted.

  19. Photoplethysmography as a single source for analysis of sleep-disordered breathing in patients with severe cardiovascular disease.

    PubMed

    Amir, Offer; Barak-Shinar, Deganit; Henry, Antonietta; Smart, Frank W

    2012-02-01

    Sleep-disordered breathing and Cheyne-Stokes breathing are often not diagnosed, especially in cardiovascular patients. An automated system based on photoplethysmographic signals might provide a convenient screening and diagnostic solution for patient evaluation at home or in an ambulatory setting. We compared event detection and classification obtained by full polysomnography (the 'gold standard') and by an automated new algorithm system in 74 subjects. Each subject underwent overnight polysomnography, 60 in a hospital cardiology department and 14 while being tested for suspected sleep-disordered breathing in a sleep laboratory. The sleep-disordered breathing and Cheyne-Stokes breathing parameters measured by a new automated algorithm system correlated very well with the corresponding results obtained by full polysomnography. The sensitivity of the Cheyne-Stokes breathing detected from the system compared to full polysomnography was 92% [95% confidence interval (CI): 78.6-98.3%] and specificity 94% (95% CI: 81.3-99.3%). Comparison of the Apnea Hyponea Index with a cutoff level of 15 shows a sensitivity of 98% (95% CI: 87.1-99.6%) and specificity of 96% (95% CI: 79.8-99.3%). The detection of respiratory events showed agreement of approximately 80%. Regression and Bland-Altman plots revealed good agreement between the two methods. Relative to gold-standard polysomnography, the simply used automated system in this study yielded an acceptable analysis of sleep- and/or cardiac-related breathing disorders. Accordingly, and given the convenience and simplicity of its application, this system can be considered as a suitable platform for home and ambulatory screening and diagnosis of sleep-disordered breathing in patients with cardiovascular disease.

  20. Variability of the breathing pattern in newborn rats: effects of ambient temperature in normoxia or hypoxia.

    PubMed

    Cameron, Y L; Merazzi, D; Mortola, J P

    2000-06-01

    We hypothesized that the inter-breath variability of the breathing pattern in newborn rats varied with temperature and oxygenation. Breathing pattern was recorded in 4-day-old rats by airflow plethysmography, during normoxia in warm (control) and cold conditions, or during hypoxia (inspired O2 = 10%) in warm or cold conditions, each lasting 15 min. The warm phase (36 degrees C) either preceded or followed the cold (24 degrees C). Time-domain analysis was applied to 500 continuous breaths recorded toward the end of each phase. All parameters describing the breathing pattern (instantaneous ventilation, tidal volume, and inspiratory and expiratory time) had lower variability when the condition differed from control i.e. in cold or hypoxia, with no correlation with the absolute level of ventilation. The difference in variability between warm-normoxia and the other conditions was reduced when cold preceded the warm phase. Gaseous metabolism was increased in cold because of thermogenesis. When the cold preceded the warm phase the increased thermogenesis partly persisted into the warm phase, raising the metabolic level. We conclude that the variability of the breathing pattern in newborn rats 1) does not depend on the absolute level of ventilation, and 2) is reduced by the increased chemical stimuli occurring during cold-hypermetabolism or hypoxia. In normoxia in warm condition metabolic and chemical stimuli are low, and the variability is the highest. The results are in agreement with the clinical observations of a higher incidence of apneic episodes in infants during warm conditions.

  1. 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

  2. Correlated variability in the breathing pattern and end-expiratory lung volumes in conscious humans.

    PubMed

    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 exponenta. 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

  3. 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

  4. 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.

  5. 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.

  6. Relationship between heart rate variability, blood pressure and arterial wall properties during air and oxygen breathing in healthy subjects.

    PubMed

    Graff, Beata; Szyndler, Anna; Czechowicz, Krzysztof; Kucharska, Wiesława; Graff, Grzegorz; Boutouyrie, Pierre; Laurent, Stephane; Narkiewicz, Krzysztof

    2013-11-01

    Previous studies reported that normobaric hyperoxia influences heart rate, arterial pressure, cardiac output and systemic vascular resistance, but the mechanisms underlying these changes are still not fully understood. Several factors are considered including degeneration of endothelium-derived nitric oxide by reactive oxygen species, the impact of oxygen-free radicals on tissues and alterations of autonomic nervous system function. Recently, new devices for the detailed non-invasive assessment of large and small arteries have been developed. Therefore, the aim of our study was to assess heart rate variability (HRV) as a potential indicator of autonomic balance and its relation to blood pressure and vascular properties during medical air (MAB) and 100% oxygen breathing (OXB) in healthy volunteers. In 12 healthy subjects we assessed heart rate and blood pressure variability, baroreflex sensitivity, respiratory frequency, common carotid artery diameter and its wall distensibility, as well as changes in the digital artery pulse waveform, stroke index and systemic vascular resistance during MAB and OXB. Mean and systolic blood pressure have increased significantly while digital pulse amplitude and carotid artery diameter were significantly lower during hyperoxia. Heart rate variability measures did not differ during MAB and OXB. However, the correlations between spectral HRV components and those hemodynamic parameters which have changed due to hyperoxia varied substantially during MAB (correlated significantly) and OXB (no significant correlations were noted). Our findings suggest that autonomic nervous system might not be the main mediator of the cardiovascular changes during 100% oxygen breathing in healthy subjects. It seems that the direct vascular responses are initial consequences of hyperoxia and other cardiovascular parameter alterations are secondary to them.

  7. Mathematical models of periodic breathing and their usefulness in understanding cardiovascular and respiratory disorders.

    PubMed

    Cherniack, Neil S; Longobardo, Guy S

    2006-03-01

    Periodic breathing is an unusual form of breathing with oscillations in minute ventilations and with repetitive apnoeas or near apnoeas. Reported initially in patients with heart failure or stroke, it was later recognized to occur especially during sleep. The recurrent hypoxia and surges of sympathetic activity that often occur during the apnoeas have serious health consequences. Mathematical models have helped greatly in the understanding of the causes of recurrent apnoeas. It is unlikely that every instance of periodic breathing has the same cause, but many result from instability in the feedback control involved in the chemical regulation of breathing caused by increased controller and plant gains and delays in information transfer. Even when it is not the main cause of the periodic breathing, unstable control modifies the ventilatory pattern and sometimes intensifies the recurrent apnoeas. The characteristics of disturbances to breathing and their interaction with the control system can be critical in determining ventilation responses and the occurrence of periodic breathing. Large abrupt changes in ventilation produced, for example, in the transition from waking to sleep and vice versa, or in the transition from breathing to apnoea, are potent factors causing periodic breathing. Mathematical models show that periodic breathing is a 'systems disorder' produced by the interplay of multiple factors. Multiple factors contribute to the occurrence of periodic breathing in congestive heart failure and cerebrovascular disease, increasing treatment options.

  8. Pre-analytic variability in cardiovascular biomarker testing

    PubMed Central

    Daves, Massimo

    2015-01-01

    The impact of laboratory medicine on clinical cardiology has dramatically increased over the years and a lot of cardiovascular biomarkers have been recently proposed. In order to avoid clinical mistakes, physicians should be well aware of all the aspects, which could affect the quality of laboratory results, remembering that pre-analytic variability is an often overlooked significant source of bias, determining the vast majority of laboratory errors. This review addresses the determinants of pre-analitycal variability in cardiovascular biomarker testing, focusing on the most widespread biomarkers, which are cardiac troponins and natriuretic peptides. PMID:26623116

  9. Heart Rate Variability and Cardiovascular Reactivity in Panic Disorder

    DTIC Science & Technology

    1999-04-01

    heart rate reactivity to cold pressor , CO2 and mental arithmetic (Roth et aI., 1992) and orthostatic... heart rates in panic disorder are inconsistent. The decreased heart rate responses to commonly used stressors, such as cold pressor , may indicate that...cardiovascular activation and heart rate variability during naturalistic anxiety and panic. Specific hypotheses to be tested included: HyPOthesis

  10. 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

  11. Characterization of the fetal diaphragmatic magnetomyogram and the effect of breathing movements on cardiac metrics of rate and variability.

    PubMed

    Gustafson, Kathleen M; Allen, John J B; Yeh, Hung-Wen; May, Linda E

    2011-07-01

    Breathing movements are one of the earliest fetal motor behaviors to emerge and are a hallmark of fetal well-being. Fetal respiratory sinus arrhythmia (RSA) has been documented but efforts to quantify the influence of breathing on heart rate (HR) and heart rate variability (HRV) are difficult due to the episodic nature of fetal breathing activity. We used a dedicated fetal biomagnetometer to acquire the magnetocardiogram (MCG) between 36 and 38 weeks gestational age (GA). We identified and characterized a waveform observed in the raw data and independent component decomposition that we attribute to fetal diaphragmatic movements during breathing episodes. RSA and increased high frequency power in a time-frequency analysis of the IBI time-series was observed during fetal breathing periods. Using the diaphragmatic magnetomyogram (dMMG) as a marker, we compared time and frequency domain metrics of heart rate and heart rate variability between breathing and non-breathing epochs. Fetal breathing activity resulted in significantly lower HR, increased high frequency power, greater sympathovagal balance, increased short-term HRV and greater parasympathetic input relative to non-breathing episodes confirming the specificity of fetal breathing movements on parasympathetic cardiac influence. No significant differences between breathing and non-breathing epochs were found in two metrics reflecting total HRV or very low, low and intermediate frequency bands. Using the fetal dMMG as a marker, biomagnetometry can help to elucidate the electrophysiologic mechanisms associated with diaphragmatic motor function and may be used to study the longitudinal development of human fetal cardiac autonomic control and breathing activity.

  12. Characterization of the Fetal Diaphragmatic Magnetomyogram and the Effect of Breathing Movements on Cardiac Metrics of Rate and Variability

    PubMed Central

    Gustafson, Kathleen M.; Allen, John J. B.; Yeh, Hung-wen; May, Linda E.

    2011-01-01

    Breathing movements are one of the earliest fetal motor behaviors to emerge andare ahallmark of fetal well-being. Fetal respiratory sinus arrhythmia (RSA) has been documented but efforts to quantify the influence of breathing on heart rate (HR) and heart rate variability (HRV) are difficult due to the episodic nature of fetal breathing activity. We used a dedicated fetal biomagnetometer to acquire the magnetocardiogram (MCG) between 36-38 weeks gestational age (GA). We identified and characterized a waveform observed in the raw data and independent component decomposition that we attribute to fetal diaphragmatic movements during breathing episodes. RSA and increased high frequency power in a time-frequency analysis of the IBI time-series was observed during fetal breathing periods. Using the diaphragmatic magnetomyogram (dMMG) as a marker, we compared time and frequency domain metrics of heartrate and heart rate variability between breathing and non-breathing epochs. Fetal breathing activity resulted in significantly lower HR, increased high frequency power, greater sympathovagal balance, increased short-term HRV andgreater parasympathetic input relative to non-breathing episodesconfirming the specificity of fetal breathing movements on parasympathetic cardiac influence. No significant differences between breathing and non-breathing epochs were found in two metrics reflecting total HRVor very low, low and intermediate frequency bands. Using the fetal dMMG as a marker, biomagnetometry can help to elucidate the electrophysiologic mechanisms associated with diaphragmatic motor function and may be used to study the longitudinal development of human fetal cardiac autonomic control and breathing activity. PMID:21497027

  13. Consciously controlled breathing decreases the high-frequency component of heart rate variability by inhibiting cardiac parasympathetic nerve activity.

    PubMed

    Sasaki, Konosuke; Maruyama, Ryoko

    2014-01-01

    Heart rate variability (HRV), the beat-to-beat alterations in heart rate, comprises sympathetic and parasympathetic nerve activities of the heart. HRV analysis is used to quantify cardiac autonomic regulation. Since respiration could be a confounding factor in HRV evaluation, some studies recommend consciously controlled breathing to standardize the method. However, it remains unclear whether controlled breathing affects HRV measurement. We compared the effects of controlled breathing on HRV with those of spontaneous breathing. In 20 healthy volunteers, we measured respiratory frequency (f), tidal volume, and blood pressure (BP) and recorded electrocardiograms during spontaneous breathing (14.8 ± 0.7 breaths/min) and controlled breathing at 15 (0.25 Hz) and 6 (0.10 Hz) breaths/min. Compared to spontaneous breathing, controlled breathing at 0.25 Hz showed a higher heart rate and a lower high-frequency (HF) component, an index of parasympathetic nerve activity, although the f was the same. During controlled breathing at 0.10 Hz, the ratio of the low frequency (LF) to HF components (LF/HF), an index of sympathetic nerve activity, increased greatly and HF decreased, while heart rate and BP remained almost unchanged. Thus, controlled breathing at 0.25 Hz, which requires mental concentration, might inhibit parasympathetic nerve activity. During controlled breathing at 0.10 Hz, LF/HF increases because some HF subcomponents are synchronized with f and probably move into the LF band. This increment leads to misinterpretation of the true autonomic nervous regulation. We recommend that the respiratory pattern of participants should be evaluated before spectral HRV analysis to correctly understand changes in autonomic nervous regulation.

  14. Cardiovascular variability and introversion/extroversion, neuroticism and psychoticism.

    PubMed

    Burdick, J A; Van Dyck, B; Von Bargen, W J

    1982-01-01

    Forty-eight subjects were measured during a 10 min rest period for pulse wave velocity (PWV) and heart rate (HR) level and variability, using a Cyborg BL 907 instrument. These subjects were also evaluated by means of the Eysenck Personality Questionnaire for I-E, N, P and L. These data were factor analyzed. Five factors were identified which were accounted for 80.6% of the variance. These factors were: 'cardiovascular lability', 'heart rate time trends', 'cardiovascular balance', 'sex effects' and 'self reports'. The EPQ measurements separated from the physiological measurements in the factor analysis and none were found to be significantly loaded on any physiological variables. On the other hand, significant physiological correlations were found with N. This study adds a possible blood pressure and heart rate descripter to N.

  15. 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...

  16. 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.

  17. Analysis of heart rate variability and skin blood flow oscillations under deep controlled breathing.

    PubMed

    Krasnikov, Gennady V; Tyurina, Miglena Y; Tankanag, Arina V; Piskunova, Galina M; Chemeris, Nikolai K

    2013-02-01

    The effect of deep breathing controlled in both rate (0.25, 0.16, 0.1, 0.07, 0.05 and 0.03 Hz) and amplitude on the heart rate variability (HRV) and respiration-dependent oscillations of forearm/finger skin blood flow (SBF) has been studied in 29 young healthy volunteers. The influence of sympathovagal balance on the respiratory sinus arrhythmia (RSA) amplitude and respiratory SBF oscillations has been studied. The subjects with predominant parasympathetic tonus had statistically significant higher RSA amplitudes in the breathing rate region of 0.03-0.07 Hz than the subjects with predominant sympathetic tonus. In the finger-cushion zone, having a well-developed sympathetic vascular innervations, the amplitudes of respiratory SBF oscillations at breathing rates 0.05 and 0.07 Hz were higher in the group of subjects with predominant parasympathetic tonus. In the forearm skin, where the density of sympathetic innervations is low comparatively to that in the finger skin, no statistically significant differences in the amplitude of respiratory SBF oscillations were found concerning the two groups of subjects.

  18. Free breathing three-dimensional late gadolinium enhancement cardiovascular magnetic resonance using outer volume suppressed projection navigators

    PubMed Central

    Menon, Rajiv G.; Miller, G.W.; Jeudy, Jean; Rajagopalan, Sanjay; Shin, Taehoon

    2017-01-01

    Purpose To develop a free-breathing, 3D late gadolinium enhancement (3D FB-LGE) cardiovascular magnetic resonance (CMR) technique and to compare it with clinically used 2D breath-hold LGE (2D BH-LGE). Methods The proposed 3D FB-LGE method consisted of inversion preparation, inversion delay, fat saturation, outer volume suppression, 1D-projection navigators, and a segmented stack of spirals acquisition. The 3D FB-LGE and 2D BH-LGE scans were performed on 29 cardiac patients. Qualitative analysis and quantitative analysis (in patients with scar) were performed. Results No significant differences were noted between the 3D FB-LGE and 2D BH-LGE datasets in terms of overall image quality score (2D: 4.69 ± 0.60 versus 3D: 4.55 ± 0.51, P = 0.46) and image artifact score (2D: 1.10 ± 0.31 versus 3D: 1.17 ± 0.38; P = 0.63). The average difference in fractional scar volume between the 3D and 2D methods was 1.9 % (n = 5). Acquisition time was significantly shorter for the 3D FB-LGE over 2D BH-LGE by a factor of 2.83 ± 0.77 (P < 0.0001). Conclusions The 3D FB-LGE is a viable option for patients, particularly in acute settings or in patients who are unable to comply with breath-hold instructions. PMID:27122450

  19. 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.

  20. 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.

  1. Effects of heart rate variability biofeedback on cardiovascular responses and autonomic sympathovagal modulation following stressor tasks in prehypertensives.

    PubMed

    Chen, S; Sun, P; Wang, S; Lin, G; Wang, T

    2016-02-01

    Autonomic dysfunction is implicated in prehypertension, and previous studies have suggested that therapies that improve modulation of sympathovagal balance, such as biofeedback and slow abdominal breathing, are effective in patients with prehypertension at rest. However, considering that psychophysiological stressors may be associated with greater cardiovascular risk in prehypertensives, it is important to investigate whether heart rate variability biofeedback (HRV-BF) results in equivalent effects on autonomic cardiovascular responses control during stressful conditions in prehypertensives. A total of 32 college students with prehypertension were enrolled and randomly assigned to HRV-BF (n=12), slow abdominal breathing (SAB, n=10) or no treatment (control, n=10) groups. Then, a training experiment consisting of 15 sessions was employed to compare the effect of each intervention on the following cardiovascular response indicators before and after intervention: heart rate (HR); heart rate variability (HRV) components; blood volume pulse amplitude (BVPamp); galvanic skin response; respiration rate (RSP); and blood pressure. In addition, the cold pressor test and the mental arithmetic challenge test were also performed over two successive days before and after the invention as well as after 3 months of follow-up. A significant decrease in HR and RSP and a significant increase in BVPamp were observed after the HRV-BF intervention (P<0.001). For the HRV analysis, HRV-BF significantly reduced the ratio of low-frequency power to high-frequency power (the LF/HF ratio, P<0.001) and increased the normalized high-frequency power (HFnm) (P<0.001) during the stress tests, and an added benefit over SAB by improving HRV was also observed. In the 3-month follow-up study, similar effects on RSP, BVPamp, LF/HF and HFnm were observed in the HRV-BF group compared with the SAB group. HRV-BF training contributes to the beneficial effect of reducing the stress-related cardiovascular

  2. Head-down bed rest reduces the breathing rate short-term variability in subjects with orthostatic intolerance.

    PubMed

    Balocchi, R; Menicucci, D; Varanini, M; Chillemi, S; Legramante, J M; Saltini, C; Raimondi, G

    2004-07-01

    Orthostatic intolerance is the most serious symptom of cardiovascular deconditioning induced by microgravity. We have showed that in symptomatic subjects the baroreflex control of sinus node is affected by short term simulated microgravity. At present the influence of the respiration on the cardiovascular system in this condition is not clear. The aim of the present study was to examine the behaviour of the Breathing Rate (BR) in 5 Non-Symptomatic (NS) and 3 Symptomatic (S) subjects before and after 4 hours of head-down bed rest (HD).

  3. Effects of ion channel noise on neural circuits: an application to the respiratory pattern generator to investigate breathing variability.

    PubMed

    Yu, Haitao; Dhingra, Rishi R; Dick, Thomas E; Galán, Roberto F

    2017-01-01

    Neural activity generally displays irregular firing patterns even in circuits with apparently regular outputs, such as motor pattern generators, in which the output frequency fluctuates randomly around a mean value. This "circuit noise" is inherited from the random firing of single neurons, which emerges from stochastic ion channel gating (channel noise), spontaneous neurotransmitter release, and its diffusion and binding to synaptic receptors. Here we demonstrate how to expand conductance-based network models that are originally deterministic to include realistic, physiological noise, focusing on stochastic ion channel gating. We illustrate this procedure with a well-established conductance-based model of the respiratory pattern generator, which allows us to investigate how channel noise affects neural dynamics at the circuit level and, in particular, to understand the relationship between the respiratory pattern and its breath-to-breath variability. We show that as the channel number increases, the duration of inspiration and expiration varies, and so does the coefficient of variation of the breath-to-breath interval, which attains a minimum when the mean duration of expiration slightly exceeds that of inspiration. For small channel numbers, the variability of the expiratory phase dominates over that of the inspiratory phase, and vice versa for large channel numbers. Among the four different cell types in the respiratory pattern generator, pacemaker cells exhibit the highest sensitivity to channel noise. The model shows that suppressing input from the pons leads to longer inspiratory phases, a reduction in breathing frequency, and larger breath-to-breath variability, whereas enhanced input from the raphe nucleus increases breathing frequency without changing its pattern.

  4. Accurate derivation of heart rate variability signal for detection of sleep disordered breathing in children.

    PubMed

    Chatlapalli, S; Nazeran, H; Melarkod, V; Krishnam, R; Estrada, E; Pamula, Y; Cabrera, S

    2004-01-01

    The electrocardiogram (ECG) signal is used extensively as a low cost diagnostic tool to provide information concerning the heart's state of health. Accurate determination of the QRS complex, in particular, reliable detection of the R wave peak, is essential in computer based ECG analysis. ECG data from Physionet's Sleep-Apnea database were used to develop, test, and validate a robust heart rate variability (HRV) signal derivation algorithm. The HRV signal was derived from pre-processed ECG signals by developing an enhanced Hilbert transform (EHT) algorithm with built-in missing beat detection capability for reliable QRS detection. The performance of the EHT algorithm was then compared against that of a popular Hilbert transform-based (HT) QRS detection algorithm. Autoregressive (AR) modeling of the HRV power spectrum for both EHT- and HT-derived HRV signals was achieved and different parameters from their power spectra as well as approximate entropy were derived for comparison. Poincare plots were then used as a visualization tool to highlight the detection of the missing beats in the EHT method After validation of the EHT algorithm on ECG data from the Physionet, the algorithm was further tested and validated on a dataset obtained from children undergoing polysomnography for detection of sleep disordered breathing (SDB). Sensitive measures of accurate HRV signals were then derived to be used in detecting and diagnosing sleep disordered breathing in children. All signal processing algorithms were implemented in MATLAB. We present a description of the EHT algorithm and analyze pilot data for eight children undergoing nocturnal polysomnography. The pilot data demonstrated that the EHT method provides an accurate way of deriving the HRV signal and plays an important role in extraction of reliable measures to distinguish between periods of normal and sleep disordered breathing (SDB) in children.

  5. Loss of Breathing Modulation of Heart Rate Variability in Patients with Recent and Long Standing Diabetes Mellitus Type II

    PubMed Central

    Estañol, Bruno; Fossion, Ruben; Toledo-Roy, Juan C.; Callejas-Rojas, José A.; Gien-López, José A.; Delgado-García, Guillermo R.; Frank, Alejandro

    2016-01-01

    Healthy subjects under rhythmic breathing have heart interbeat intervals with a respiratory band in the frequency domain that can be an index of vagal activity. Diabetes Mellitus Type II (DM) affects the autonomic nervous system of patients, thus it can be expected changes on the vagal activity. Here, the influence of DM on the breathing modulation of the heart rate is evaluated by analyzing in the frequency domain heart interbeat interval (IBI) records obtained from 30 recently diagnosed, 15 long standing DM patients, and 30 control subjects during standardized clinical tests of controlled breathing at 0.1 Hz, supine rest and standing upright. Fourier spectral analysis of IBI records quantifies heart rate variability in different regions: low-frequencies (LF, 0.04–0.15 Hz), high-frequencies (HF, 0.15–0.4 Hz), and a controlled breathing peak (RP, centered around 0.1 Hz). Two new parameters are introduced: the frequency radius rf (square root of the sum of LF and HF squared) and β (power of RP divided by the sum of LF and HF). As diabetes evolves, the controlled breathing peak loses power and shifts to smaller frequencies, indicating that heart rate modulation is slower in diabetic patients than in controls. In contrast to the traditional parameters LF, HF and LF/HF, which do not show significant differences between the three populations in neither of the clinical tests, the new parameters rf and β, distinguish between control and diabetic subjects in the case of controlled breathing. Sympathetic activity that is driven by the baroreceptor reflex associated with the 0.1 Hz breathing modulations is affected in DM patients. Diabetes produces not only a rigid heartbeat with less autonomic induced variability (rf diminishes), but also alters the coupling between breathing and heart rate (reduced β), due to a progressive decline of vagal and sympathetic activity. PMID:27802329

  6. Loss of Breathing Modulation of Heart Rate Variability in Patients with Recent and Long Standing Diabetes Mellitus Type II.

    PubMed

    Rivera, Ana Leonor; Estañol, Bruno; Fossion, Ruben; Toledo-Roy, Juan C; Callejas-Rojas, José A; Gien-López, José A; Delgado-García, Guillermo R; Frank, Alejandro

    2016-01-01

    Healthy subjects under rhythmic breathing have heart interbeat intervals with a respiratory band in the frequency domain that can be an index of vagal activity. Diabetes Mellitus Type II (DM) affects the autonomic nervous system of patients, thus it can be expected changes on the vagal activity. Here, the influence of DM on the breathing modulation of the heart rate is evaluated by analyzing in the frequency domain heart interbeat interval (IBI) records obtained from 30 recently diagnosed, 15 long standing DM patients, and 30 control subjects during standardized clinical tests of controlled breathing at 0.1 Hz, supine rest and standing upright. Fourier spectral analysis of IBI records quantifies heart rate variability in different regions: low-frequencies (LF, 0.04-0.15 Hz), high-frequencies (HF, 0.15-0.4 Hz), and a controlled breathing peak (RP, centered around 0.1 Hz). Two new parameters are introduced: the frequency radius rf (square root of the sum of LF and HF squared) and β (power of RP divided by the sum of LF and HF). As diabetes evolves, the controlled breathing peak loses power and shifts to smaller frequencies, indicating that heart rate modulation is slower in diabetic patients than in controls. In contrast to the traditional parameters LF, HF and LF/HF, which do not show significant differences between the three populations in neither of the clinical tests, the new parameters rf and β, distinguish between control and diabetic subjects in the case of controlled breathing. Sympathetic activity that is driven by the baroreceptor reflex associated with the 0.1 Hz breathing modulations is affected in DM patients. Diabetes produces not only a rigid heartbeat with less autonomic induced variability (rf diminishes), but also alters the coupling between breathing and heart rate (reduced β), due to a progressive decline of vagal and sympathetic activity.

  7. Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control.

    PubMed

    Valenza, Gaetano; Citi, Luca; Garcia, Ronald G; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

    2017-02-20

    The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson's Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity.

  8. Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control

    PubMed Central

    Valenza, Gaetano; Citi, Luca; Garcia, Ronald G.; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

    2017-01-01

    The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson’s Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity. PMID:28218249

  9. Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control

    NASA Astrophysics Data System (ADS)

    Valenza, Gaetano; Citi, Luca; Garcia, Ronald G.; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

    2017-02-01

    The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson’s Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity.

  10. Influence of deep breathing exercise on spontaneous respiratory rate and heart rate variability: a randomised controlled trial in healthy subjects.

    PubMed

    Tharion, Elizabeth; Samuel, Prasanna; Rajalakshmi, R; Gnanasenthil, G; Subramanian, Rajam Krishna

    2012-01-01

    Studies show that yogic type of breathing exercises reduces the spontaneous respiratory rate. However, there are no conclusive studies on the effects of breathing exercise on heart rate variability. We investigated the effects of non-yogic breathing exercise on respiratory rate and heart rate variability. Healthy subjects (21-33 years, both genders) were randomized into the intervention group (n=18), which performed daily deep breathing exercise at 6 breaths/min (0.1 Hz) for one month, and a control group (n=18) which did not perform any breathing exercise. Baseline respiratory rate and short-term heart rate variability indices were assessed in both groups. Reassessment was done after one month and the change in the parameters from baseline was computed for each group. Comparison of the absolute changes [median (inter-quartile ranges)] of the parameters between the intervention and control group showed a significant difference in the spontaneous respiratory rate [intervention group -2.50 (-4.00, -1.00), control group 0.00 (-1.00, 1.00), cycles/min, P<0.001], mean arterial pressure [intervention group -0.67 (-6.67, 1.33), control group 0.67 (0.00, 6.67), mmHg, (P<0.05)], high frequency power [intervention group 278.50 (17.00, 496.00), control group -1.00 (-341.00, 196.00), ms2 P<0.05] and sum of low and high frequency powers [intervention group 512.00 (-73.00, 999.00), control group 51.00 (-449.00, 324.00), ms2, P<0.05]. Neither the mean of the RR intervals nor the parameters reflecting sympatho-vagal balance were significantly different across the groups. In conclusion, the changes produced by simple deep slow breathing exercise in the respiratory rate and cardiac autonomic modulation of the intervention group were significant, when compared to the changes in the control group. Thus practice of deep slow breathing exercise improves heart rate variability in healthy subjects, without altering their cardiac autonomic balance. These findings have implications in the

  11. Obesity accentuates circadian variability in breathing during sleep in mice but does not predispose to apnea.

    PubMed

    Davis, Eric M; Locke, Landon W; McDowell, Angela L; Strollo, Patrick J; O'Donnell, Christopher P

    2013-08-15

    Obesity is a primary risk factor for the development of obstructive sleep apnea in humans, but the impact of obesity on central sleep apnea is less clear. Given the comorbidities associated with obesity in humans, we developed techniques for long-term recording of diaphragmatic EMG activity and polysomnography in obese mice to assess breathing patterns during sleep and to determine the effect of obesity on apnea generation. We hypothesized that genetically obese ob/ob mice would exhibit less variability in breathing across the 24-h circadian cycle, be more prone to central apneas, and be more likely to exhibit patterns of increased diaphragm muscle activity consistent with obstructive apneas compared with lean mice. Unexpectedly, we found that obese mice exhibited a greater circadian impact on respiratory rate and diaphragmatic burst amplitude than lean mice, particularly during rapid eye movement (REM) sleep. Central apneas were more common in REM sleep (42 ± 17 h(-1)) than non-REM (NREM) sleep (14 ± 5 h(-1)) in obese mice (P < 0.05), but rates were not different between lean and obese mice in either sleep state. Even after experimentally enhancing central apnea generation by acute withdrawal of hypoxic chemoreceptor activation during sleep, central apnea rates remained comparable between lean and obese mice. Last, we were unable to detect patterns of diaphragmatic burst activity suggestive of obstructive apnea events in obese mice. In summary, obesity does not predispose mice to increased occurrence of central or obstructive apneas during sleep, but does lead to a more pronounced circadian variability in respiration.

  12. 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.

  13. 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.

  14. 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.

  15. Information domain analysis of cardiovascular variability signals: evaluation of regularity, synchronisation and co-ordination.

    PubMed

    Porta, A; Guzzetti, S; Montano, N; Pagani, M; Somers, V; Malliani, A; Baselli, G; Cerutti, S

    2000-03-01

    A unifying general approach to measure regularity, synchronisation and co-ordination is proposed. This approach is based on conditional entropy and is specifically designed to deal with a small amount of data (a few hundred samples). Quantitative and reliable indexes of regularity, synchronisation and co-ordination (ranging from 0 to 1) are derived in a domain (i.e. the information domain) different from time and frequency domains. The method is applied to evaluate regularity, synchronisation and co-ordination among cardiovascular beat-to-beat variability signals during sympathetic activation induced by head-up tilt (T), during the perturbing action produced by controlled respiration at 10, 15 and 20 breaths/min (CR10, CR15 and CR20), and after peripheral muscarinic blockade provoked by the administration of low and high doses of atropine (LD and HD). It is found that: (1) regularity of the RR interval series is around 0.209; (2) this increases during T, CR10 and HD; (3) the systolic arterial pressure (SAP) series is more regular (0.406) and its regularity is not affected by the specified experimental conditions; (4) the muscle sympathetic (MS) series is a complex signal (0.093) and its regularity is not influenced by HD and LD; (5) the RR interval and SAP series are significantly, though weakly, synchronised (0.093) and their coupling increases during T, CR10 and CR15; (6) the RR interval and respiration are coupled (0.152) and their coupling increases during CR10; (7) SAP and respiration are significantly synchronised (0.108) and synchronisation increases during CR10; (8) MS and respiration are uncoupled and become coupled (0.119) after HD; (9) the RR interval, SAP and respiration are significantly co-ordinated (0.118) and co-ordination increases during CR10 and CR15; (10) during HD the co-ordination among SAP, MS and the respiratory signal is larger than that among the RR interval, SAP, MS and the respiratory signal, thus indicating that the RR interval

  16. Associations between body fat variability and later onset of cardiovascular disease risk factors

    PubMed Central

    Takahashi, Osamu; Arioka, Hiroko; Kobayashi, Daiki

    2017-01-01

    Objective There is current debate regarding whether body weight variability is associated with cardiovascular events. Recently, high body fat percentage (BF%) has been shown to be a cardiovascular risk factor. We therefore hypothesized that BF% variability would present a stronger cardiovascular risk than body weight variability. Methods A single-center retrospective cohort study of medical check-up examinees aged 20 years or older at baseline (2005) was performed. Examinees were followed in 2007, 2009, and 2013–2014. BF% variability in 2005, 2007 and 2009 was calculated as the root-mean square error (RMSE) using a simple linear regression model. Multiple logistic regression models estimated the association between BF%-RMSE and new diagnoses of cardiovascular risk factors occurring between the 2009 and 2013–2014 visits. Results In total, 11,281 participants (mean age: 51.3 years old, 48.8% were male) were included in this study. The average BF%-RMSE of our subjects was 0.63, and the average BMI-RMSE was 0.24. The high BF%-RMSE group (76-100th percentile) had a higher incidence of hypertension and a lower incidence of diabetes mellitus than the low BF%-RMSE group (1-25th percentile). This tendency was particularly evident in male participants. BMI-RMSE was not associated with any cardiovascular risks in our study. Conclusions This study indicates that body fat variability has contrasting effects on cardiovascular risk factors, while body weight variability has no significant effects. PMID:28369119

  17. 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...

  18. Increase in the heart rate variability with deep breathing in diabetic patients after 12-month exercise training.

    PubMed

    Sridhar, Bhagyalakshmi; Haleagrahara, Nagaraja; Bhat, Ramesh; Kulur, Anupama Bangra; Avabratha, Sridhar; Adhikary, Prabha

    2010-02-01

    Autonomic neuropathy in diabetes leads to impaired regulation of blood pressure and heart rate variability (HRV), which is due to a shift in cardiac autonomic balance towards sympathetic dominance. Lower HRV has been considered a predictor of cardiac mortality and morbidity. Deep breathing test is a simple method to measure HRV and it provides a sensitive measure of cardiac autonomic function. The effect of long-term physical activity on HRV in type-2 diabetes mellitus is inconclusive. We aimed to evaluate the effects of regular physical exercise on HRV with deep breathing in type 2 diabetes (n = 105). Thirty normotensive diabetic patients and 25 hypertensive diabetic patients underwent physical exercise program for 12 months, and the other 50 patients (22 normotensive and 28 hypertensive diabetic patients) were considered the non-exercised group. Electrocardiogram was recorded during deep breathing and HRV was measured. Regular exercise significantly increased HRV in diabetic patients with and without hypertension. The degree of the increase in HRV was greater in hypertensive diabetic patients (p < 0.01) than in normotensive diabetic patients (p < 0.05). After exercise, glycosylated hemoglobin levels were decreased in both groups of diabetic patients. Moreover, the hypertensive diabetic patients showed a decrease (p < 0.05) in blood pressure after regular exercise. Thus, regular exercise training increases HRV, suggesting that there is a shift in the cardiac sympathovagal balance in favor of parasympathetic dominance in diabetic patients. Long-term physical training may be an effective means to reverse the autonomic dysregulation seen in type 2 diabetes.

  19. 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...

  20. 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

  1. Breathing metabolic simulator

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

    The development of a breathing metabolic simulator (BMS) is reported. This BMS simulates all of the breathing and metabolic parameters required for complete evaluation and test of life support and resuscitation equipment. It is also useful for calibrating and validating mechanical and gaseous pulmonary function test procedures. Breathing rate, breathing depth, breath velocity contour, oxygen uptake, and carbon dioxide release are all variable over wide ranges simulating conditions from sleep to hard work with respiratory exchange ratios covering the range from hypoventilation. In addition, all of these parameters are remotely controllable to facilitate use of the device in hostile or remote environments. The exhaled breath is also maintained at body temperature and a high humidity. The simulation is accurate to the extent of having a variable functional residual capacity independent of other parameters.

  2. Bad Breath

    MedlinePlus

    ... Emergency Room? What Happens in the Operating Room? Bad Breath KidsHealth > For Kids > Bad Breath A A ... visit your dentist or doctor . continue What Causes Bad Breath? Here are three common causes of bad ...

  3. Comparison of sleep-disordered breathing and heart rate variability between hemodialysis and non-hemodialysis days in hemodialysis patients.

    PubMed

    Sukegawa, Mayo; Noda, Akiko; Soga, Taro; Adachi, Yuki; Tsuruta, Yoshinari; Ozaki, Norio; Koike, Yasuo

    2008-08-01

    Sleep disturbances manifesting as insomnia, daytime sleepiness, fatigue, and other symptoms are frequently found in patients with end-stage renal disease that is being treated with dialysis. Many factors, including neurosis, uremic symptoms, dialysis drugs, and sleep-wake rhythms have been suggested as potential causes for these sleep disturbances. We examined sleep apnea/hypopnea and heart rate variability (HRV) reflecting autonomic activity in hemodialysis patients on their hemodialysis and non-hemodialysis days using a home medical care device (Morpheus C, TEIJIN). Eleven hemodialysis patients and 14 healthy adults were enrolled in this study. We calculated the number of apnea/hypopnea episodes per hour (apnea/hypopnea index: AHI) and HRV (percentage of R-R intervals that differ by at least 50 ms from the previous interval: pNN50, very low frequency: VLF, low frequency: LF, high frequency: HF and LF/ HF). There was no significant difference in the AHI between hemodialysis and non-hemodialysis days. The heart rate in hemodialysis patients on non-hemodialysis days was significantly higher than in the controls, whereas the pNN50 was significantly lower in hemodialysis patients on non-hemodialysis days than in the controls. Although VLF was significantly lower in hemodialysis patients on non-hemodialysis days compared to the controls, there were no significant differences in LF, HF or LF/HF between the two groups. Hemodialysis itself might not be an important contributing factor in sleep-related breathing disturbances. The simultaneous analysis of HRV reflecting autonomic activity and sleep-disordered breathing on both hemodialysis and non-hemodialysis days provides important information.

  4. Blood Pressure Variability: Can Nonlinear Dynamics Enhance Risk Assessment During Cardiovascular Surgery? A Feasibility Study

    PubMed Central

    Subramaniam, Balachundhar; Khabbaz, Kamal R.; Heldt, Thomas; Lerner, Adam B.; Mittleman, Murray A.; Davis, Roger B.; Goldberger, Ary L.; Costa, Madalena D.

    2014-01-01

    Brief Summary We propose that complex (nonlinear) fluctuations of hemodynamic variables (including systemic blood pressure parameters) during cardiovascular surgery contain information relevant to risk assessment and intraoperative management. Preliminary analysis of a pilot study supports the feasibility and potential merits of performing a larger, prospective study to assess the clinical utility of such new dynamical measures and to evaluate their potential role in enhancing contemporary approaches to risk assessment of major adverse events. PMID:24508020

  5. Sleep-Disordered Breathing in Chronic SCI: A Randomized Controlled Trial of Treatment Impact on Cognition, Quality of Life, and Cardiovascular Disease

    DTIC Science & Technology

    2014-10-01

    AWARD NUMBER: W81XWH-13-1-0479 TITLE: Sleep-Disordered Breathing in Chronic SCI: A...5a. CONTRACT NUMBER Sleep-Disordered Breathing in Chronic SCI: A Randomized Controlled Trial of Treatment Impact on Cognition...SCI. In this prospective randomized controlled trial, we will objectively measure sleep disordered breathing (SDB) in chronic SCI patients using

  6. Contrasting effects of phentolamine and nitroprusside on neural and cardiovascular variability.

    PubMed

    van de Borne, P; Rahnama, M; Mezzetti, S; Montano, N; Porta, A; Degaute, J P; Somers, V K

    2001-08-01

    The relative contributions of a central neural oscillator and of the delay in alpha-adrenergic transmission within the baroreflex loop in the predominance of low-frequency (LF) cardiovascular variability during sympathetic activation in humans are unclear. We measured R-R interval (RR), muscle sympathetic nerve activity (MSNA), blood pressure (BP), and their variability in 10 normal subjects during sympathetic activation achieved by BP lowering with sodium nitroprusside (SNP) and alpha-adrenergic blockade using phentolamine. SNP and phentolamine induced comparable reductions in BP (P > 0.25). Despite tachycardia and sympathetic activation with both SNP and phentolamine, LF variability in RR, MSNA, and BP increased during SNP and decreased during phentolamine (SNP: RR +20 +/- 6%, MSNA +3 +/- 5%, systolic BP +9 +/- 6%, diastolic BP +7 +/- 5%; phentolamine: RR -2 +/- 7%, MSNA -34 +/- 6%, systolic BP -16 +/- 8%, diastolic BP -13 +/- 4%, P < 0.05 except systolic BP, where P = 0.09). Thus LF variability is reduced when sympathetic activation is induced by alpha-adrenergic blockade. This suggests that alpha-adrenergic transmission within the baroreflex loop may contribute importantly to the predominance of LF cardiovascular variability associated with sympathetic excitation in humans.

  7. Breathing difficulty

    MedlinePlus

    ... difficulty in which you make a high-pitched sound when you breathe out. Causes Shortness of breath has many different causes. For ... episode have a similar pattern? Does breathing difficulty cause you to wake up at ... or wheezing sounds while breathing? Tests that may be ordered include: ...

  8. Basic cardiovascular variability signals: mutual directed interactions explored in the information domain.

    PubMed

    Javorka, Michal; Krohova, Jana; Czippelova, Barbora; Turianikova, Zuzana; Lazarova, Zuzana; Javorka, Kamil; Faes, Luca

    2017-01-31

    The study of short-term cardiovascular interactions is classically performed through the bivariate analysis of the interactions between the beat-to-beat variability of heart period (RR interval from the ECG) and systolic blood pressure (SBP). Recent progress in the development of multivariate time series analysis methods is making it possible to explore how directed interactions between two signals change in the context of networks including other coupled signals. Exploiting these advances, the present study aims at assessing directional cardiovascular interactions among the basic variability signals of RR, SBP and diastolic blood pressure (DBP), using an approach which allows direct comparison between bivariate and multivariate coupling measures. To this end, we compute information-theoretic measures of the strength and delay of causal interactions between RR, SBP and DBP using both bivariate and trivariate (conditioned) formulations in a group of healthy subjects in a resting state and during stress conditions induced by head-up tilt (HUT) and mental arithmetics (MA). We find that bivariate measures better quantify the overall (direct+indirect) information transferred between variables, while trivariate measures better reflect the existence and delay of directed interactions. The main physiological results are: (i) the detection during supine rest of strong interactions along the pathway RR���DBP���SBP, reflecting marked Windkessel and/or Frank-Starling effects; (ii) the finding of relatively weak baroreflex effects SBP���RR at rest; (iii) the invariance of cardiovascular interactions during MA, and the emergence of stronger and faster SBP���RR interactions, as well as of weaker RR���DBP interactions, during HUT. These findings support the importance of investigating cardiovascular interactions from a network perspective, and suggest the usefulness of directed information measures to assess physiological mechanisms and track their

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

    PubMed

    Buchner, Teodor; Petelczyc, Monika; Zebrowski, 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.

  10. Impaired heart rate variability as a marker of cardiovascular autonomic dysfunction in multiple sclerosis.

    PubMed

    Tombul, Temel; Anlar, Omer; Tuncer, Mustafa; Huseyinoglu, Nergis; Eryonucu, Beyhan

    2011-06-01

    Multiple sclerosis (MS) can cause alterations in autonomic cardiovascular functions. We aimed to investigate the correlation of disease activity and disability with heart rate variability (HRV) of cardiovascular autonomic dysfunction (CAD) demonstrated by 24-h Holter monitorization. Thirty-four patients with clinically active relapsing-remitting MS, age 33.8 +/- 7.6 years, were studied. Twenty healthy volunteers served as controls. The time domain long-term HRV parameters were recorded by a digicorder recorder calculated by ambulatory electrocardiograms. Variabilities in time domain were lower in the MS patients: SDNN (standard deviation of all R-R intervals, p = 0,019), SDANN (standard deviation of the averages of R-R intervals in all 5-minute segments of the entire recordings, p = 0,040), RMSSD (the square root of the mean of the sum of the squares of differences between adjacent R-R intervals, p = 0,026), HRVM (mean of the SDNN in all the 5-minute intervals, p = 0,029), HRVSD (standard deviation of the SDNN in all the 5-minute, p = 0,043). These results suggest that MS causes CAD manifesting as long-term HRV abnormalities. This illness seems to cause a dysfunction in parasympathetic cardiovascular tone. Depressed HRV parameters are independent from the clinicalfindings, but the illness progression partially seems to provoke a decrease in such parameters.

  11. Power spectrum analysis of cardiovascular variability during passive heating in conscious rats.

    PubMed

    Moura, Anselmo Gomes; Pires, Washington; Leite, Laura Hora Rios; da Cunha, Daise Nunes Queiroz; Peçanha, Tiago; de Lima, Jorge Roberto Peurrot; Natali, Antônio José; Prímola-Gomes, Thales Nicolau

    2016-12-01

    The cardiovascular system plays a direct role in the maintenance of body temperature. Whether passive heating alters cardiovascular autonomic modulation in conscious rats is still unknown. This study investigated the effects of passive heating on systolic blood pressure variability (SBPV) and heart rate variability (HRV) in conscious rats and the involvement of the renin-angiotensin system in the passive heating effects on SBPV and HRV. Fourteen male Wistar rats were randomly assigned to the control group or the losartan treatment group. A catheter was implanted in the left carotid artery to record pulsatile arterial pressure (PAP), and a telemetry sensor was implanted in the abdominal cavity to measure body temperature (Tbody). After recovering from surgery, the animals were subjected to a passive heating protocol (35°C; 30min) in resting conditions, during which Tbody, tail skin temperature and PAP were measured. The mean arterial pressure, systolic and diastolic blood pressure, heart rate, double product (i.e., the product of systolic blood pressure by heart rate), SBPV and HRV were calculated from the PAP. SBPV and HRV were analyzed in terms of both time and frequency domains. Increases in the thermoregulatory and cardiovascular parameters were observed during passive heating in both groups, and those increases were reflected in the higher time and frequency domains of the SBPV. However, passive heating was not effective in altering HRV. Passive heating altered SBPV but not HRV in conscious rats when they were treated with losartan.

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

    PubMed

    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.

  13. Application of cardiovascular models in comparative physiology and blood pressure variability.

    PubMed

    Avolio, Alberto P; Xu, Ke; Butlin, Mark

    2013-01-01

    The usefulness of cardiovascular models is determined by their intended function with respect to elucidating underlying hemodynamic concepts and to enable simulations that will assist in understanding the effects of specific parameters. Models can take different forms, including mock circulatory constructs with physical components, mathematical representations of parameter space relations employing constitutive equations, or closed form representations of electrical circuit analogs described in the time or frequency domain. This investigation describes the use of cardiovascular models based on electrical analogs of mechanical hydrodynamic systems to elucidate two different physiologic concepts: (i) the use of distributed vascular impedance to investigate comparative physiology of optimal design and features related to body size across a broad range of animal species; (ii) use of lumped parameter models to assess the role of arterial stiffness in blood pressure variability. The impedance model shows that an allometric relationship between body weight and aortic effective length can be determined by using the frequency of minimum input impedance and aortic pulse wave velocity. This concept provides a background for optimal matching of body size and hemodynamic load on the heart. The lumped parameter model indicates that arterial stiffness, simulated by the total arterial compliance term, has a significant impact on variability of arterial pressure when changes are due to dynamic alterations of peripheral resistance. In addition, the known pressure dependency of arterial stiffness results in a curvilinear relationship between blood pressure variability and mean pressure. This has implications in hypertensive treatment where there are marked changes in arterial stiffness, as occurs with aging.

  14. 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).

  15. A MATLAB toolbox for correcting within-individual effects of respiration rate and tidal volume on respiratory sinus arrhythmia during variable breathing.

    PubMed

    Schulz, Stefan M; Ayala, Erica; Dahme, Bernhard; Ritz, Thomas

    2009-11-01

    Respiratory sinus arrhythmia (RSA) is a common estimator of vagal outflow to the heart, dependent on parasympathetic activity. During variable breathing, both respiration rate and tidal volume contribute substantially to within-individual RSA variance. A respiratory control method allows for within-individual correction of the time-domain index of RSA. rsaToolbox is a set of MATLAB programs for scoring respiration-corrected RSA using measurements of cardiac interbeat intervals, respiratory-cycle times, and tidal volumes, recorded at different paced-breathing frequencies. The within-individual regression of RSA divided by tidal volume upon total respiratory cycle time is then used to estimate the baseline vagal tone for each breath of a given total respiratory-cycle time. During a subsequent analysis, the difference between the observed RSA (divided by the tidal volume at each breath) and the RSA divided by the tidal volume that was predicted by the baseline equation serves as an estimate of changes in vagal tone. rsaToolbox includes a graphical user interface for intuitive handling. Modular implementation of the algorithm also allows for flexible integration within other analytic strategies or for batch processing.

  16. 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

  17. Breathing Problems

    MedlinePlus

    ... getting enough air. Sometimes you can have mild breathing problems because of a stuffy nose or intense ... panic attacks Allergies If you often have trouble breathing, it is important to find out the cause.

  18. Bad Breath

    MedlinePlus

    ... breath? Maybe you shouldn't have put extra onions on your hamburger at lunch. What's a kid ... bad breath: foods and drinks, such as garlic, onions, cheese, orange juice, and soda poor dental hygiene ( ...

  19. Slow breathing and hypoxic challenge: cardiorespiratory consequences and their central neural substrates.

    PubMed

    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.

  20. 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

  1. Lamaze Breathing

    PubMed Central

    Lothian, Judith A.

    2011-01-01

    Lamaze breathing historically is considered the hallmark of Lamaze preparation for childbirth. This column discusses breathing in the larger context of contemporary Lamaze. Controlled breathing enhances relaxation and decreases perception of pain. It is one of many comfort strategies taught in Lamaze classes. In restricted birthing environments, breathing may be the only nonpharmacological comfort strategy available to women. Conscious breathing and relaxation, especially in combination with a wide variety of comfort strategies, can help women avoid unnecessary medical intervention and have a safe, healthy birth. PMID:22379360

  2. Chest associated to motor physiotherapy improves cardiovascular variables in newborns with respiratory distress syndrome

    PubMed Central

    2011-01-01

    Background We aimed to evaluate the effects of chest and motor physiotherapy treatment on hemodynamic variables in preterm newborns with respiratory distress syndrome. Methods We evaluated heart rate (HR), respiratory rate (RR), systolic (SAP), mean (MAP) and diastolic arterial pressure (DAP), temperature and oxygen saturation (SO2%) in 44 newborns with respiratory distress syndrome. We compared all variables between before physiotherapy treatment vs. after the last physiotherapy treatment. Newborns were treated during 11 days. Variables were measured 2 minutes before and 5 minutes after each physiotherapy treatment. We applied paired Student t test to compare variables between the two periods. Results HR (148.5 ± 8.5 bpm vs. 137.1 ± 6.8 bpm - p < 0.001), SAP (72.3 ± 11.3 mmHg vs. 63.6 ± 6.7 mmHg - p = 0.001) and MAP (57.5 ± 12 mmHg vs. 47.7 ± 5.8 mmHg - p = 0.001) were significantly reduced after 11 days of physiotherapy treatment compared to before the first session. There were no significant changes regarding RR, temperature, DAP and SO2%. Conclusions Chest and motor physiotherapy improved cardiovascular parameters in respiratory distress syndrome newborns. PMID:22029840

  3. Factors influencing breath ammonia determination.

    PubMed

    Solga, Steven F; Mudalel, Matthew; Spacek, Lisa A; Lewicki, Rafal; Tittel, Frank; Loccioni, Claudio; Russo, Adolfo; Risby, Terence H

    2013-09-01

    Amongst volatile compounds (VCs) present in exhaled breath, ammonia has held great promise and yet it has confounded researchers due to its inherent reactivity. Herein we have evaluated various factors in both breath instrumentation and the breath collection process in an effort to reduce variability. We found that the temperature of breath sampler and breath sensor, mouth rinse pH, and mode of breathing to be important factors. The influence of the rinses is heavily dependent upon the pH of the rinse. The basic rinse (pH 8.0) caused a mean increase of the ammonia concentration by 410 ± 221 ppb. The neutral rinse (pH 7.0), slightly acidic rinse (pH 5.8), and acidic rinse (pH 2.5) caused a mean decrease of the ammonia concentration by 498 ± 355 ppb, 527 ± 198 ppb, and 596 ± 385 ppb, respectively. Mode of breathing (mouth-open versus mouth-closed) demonstrated itself to have a large impact on the rate of recovery of breath ammonia after a water rinse. Within 30 min, breath ammonia returned to 98 ± 16% that of the baseline with mouth open breathing, while mouth closed breathing allowed breath ammonia to return to 53 ± 14% of baseline. These results contribute to a growing body of literature that will improve reproducibly in ammonia and other VCs.

  4. Non-uniform multivariate embedding to assess the information transfer in cardiovascular and cardiorespiratory variability series.

    PubMed

    Faes, Luca; Nollo, Giandomenico; Porta, Alberto

    2012-03-01

    The complexity of the short-term cardiovascular control prompts for the introduction of multivariate (MV) nonlinear time series analysis methods to assess directional interactions reflecting the underlying regulatory mechanisms. This study introduces a new approach for the detection of nonlinear Granger causality in MV time series, based on embedding the series by a sequential, non-uniform procedure, and on estimating the information flow from one series to another by means of the corrected conditional entropy. The approach is validated on short realizations of linear stochastic and nonlinear deterministic processes, and then evaluated on heart period, systolic arterial pressure and respiration variability series measured from healthy humans in the resting supine position and in the upright position after head-up tilt.

  5. Cardiovascular reactivity during public speaking as a function of personality variables.

    PubMed

    Fichera, L V; Andreassi, J L

    2000-09-01

    An experiment was conducted to assess the effects of a real-life stressor (public speaking) upon cardiovascular reactivity (CVR). Changes in blood pressure and heart rate from baseline to task were measured in a sample of 86 men and women. The purpose was to examine the effects of individual differences (Type A personality, hostility and gender) on CVR. Participants gave a 6-min oral presentation during which they were evaluated by their professor and with classmates as the audience. Results indicated that all participants had marked CVR during public speaking. There were differences in reactivity patterns between men and women, but personality did not play a role except for high hostile men. It is suggested that intense stressors may result in high levels of CVR independent of personality variables that moderate reactivity at lower levels of stress.

  6. 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

    2015-05-14

    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.

  7. Influence of acute progressive hypoxia on cardiovascular variability in conscious spontaneously hypertensive rats

    PubMed Central

    Sugimura, Mitsutaka; Hirose, Yohsuke; Hanamoto, Hiroshi; Okada, Kenji; Boku, Aiji; Morimoto, Yoshinari; Taki, Kunitaka; Niwa, Hitoshi

    2008-01-01

    The purpose of this study is to examine the influence of acute progressive hypoxia on cardiovascular variability and striatal dopamine (DA) levels in conscious, spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). After preparation for measurement, the inspired oxygen concentration of rats was decreased to 10% within 5 min (descent stage), maintained at 10% for 10 min (fixed stage), and then elevated back to 20% over 5 min (recovery stage). The systolic blood pressure (SBP) and heart rate (HR) variability at each stage was calculated to evaluate the autonomic nervous system response using the wavelet method. Striatal DA during each stage was measured using in vivo microdialysis. We found that SHR showed a more profound hemodynamic response to progressive hypoxia as compared to WKY. Cardiac parasympathetic activity in SHR was significantly inhibited by acute progressive hypoxia during all stages, as shown by the decrease in the high frequency band of HR variability (HR-HF), along with transient increase in sympathetic activity during the early hypoxic phase. This decrease in the HR-HF continued even when SBP was elevated. Striatal DA levels showed the transient similar elevation in both groups. These findings suggest that acute progressive hypoxic stress in SHR inhibits cardiac parasympathetic activity through reduction of baroreceptor reflex sensitivity, with potentially severe deleterious effects on circulation, in particular on HR and circulatory control. Furthermore, it is thought that the influence of acute progressive hypoxia on striatal DA levels is similar in SHR and WKY. PMID:18599365

  8. [Estimating cardiovascular age of civil flying personnel by means of heart rate and blood pressure variability analysis].

    PubMed

    Niu, Y G; Zhang, L F; Zhang, Y H; Wang, S Y; Xu, X Y; Su, J X; Yan, Y B

    2001-06-01

    Objective. To estimate the cardiovascular age of civil flying personnel by means of heart rate and blood pressure variability analysis and to evaluate its significance in aviation medicine. Method. First, heart rate variability (HRV), blood pressure variability (BPV) and spontaneous baroreflex sensitivity (BRS) were analyzed among 89 healthy civil flying personnel by using conventional AR spectral analysis and sequence method respectively. Then, principal component analysis was conducted over original and derived variables of HRV and BPV spectral and BRS data. Finally, by the use of multiple regression in which the chronological age acted as the dependent variable and the components significantly related to age were used as the regressors, the equation for estimating the cardiovascular age was established. Result. Only seven principal components can exactly reflect the same information of autonomic regulatory function which was embodied in the 17 variables of HRV and BPV spectral and BRS parameters. Among the seven principal components, the PC2orig, PC4orig and PC2deri were negatively correlated with chronological age (P<0.05), whereas the PC3orig was positively correlated with the chronological age (P<0.01). The cardiovascular age derived from the equation was significantly correlated with the chronological age of the civil flying personnel (r= 0.73, P<0.01). Conclusion. The cardiovascular age estimated by means of a multi-variate analysis of HRV, BPV and BRS can be treated as a comprehensive indicator reflecting the age dependency of autonomic regulatory function of cardiovascular system in healthy civil flying personnel, and its interpretation and significance in application are surely worthy of further and fully dedicated efforts.

  9. 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.

  10. 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

  11. 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.

  12. Bad Breath

    MedlinePlus

    ... for lunch. But certain strong-smelling foods like onions and garlic can cause bad breath. So can ... leave behind strong smells, like cabbage, garlic, raw onions, and coffee. If you’re trying to lose ...

  13. Breath odor

    MedlinePlus

    ... drain their stomach. The breath may have an ammonia-like odor (also described as urine-like or " ... Is there a specific odor (such as fish, ammonia, fruit, feces, or alcohol)? Have you recently eaten ...

  14. 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

  15. Sleep-disordered breathing in chronic heart failure is highly variable when measured remotely using a novel non-contact biomotion sensor.

    PubMed

    McDonald, Kenneth; O'Hanlon, Rory; Savage, Henry Oluwasefunmi; Khushaba, Rami N; Colefax, Michael; Farrugia, Steven; Javed, Faizan; Schindhelm, Klaus; Wilcox, Ian; Cowie, Martin R

    2017-03-21

    We used a remotely monitored non-contact biosensor (SleepMinder™) to measure breathing during sleep (SDB) in a prospective study of 91 patients with stable class II to IV heart failure (HF). The device algorithm measures a surrogate of the traditional apnoea/hypopnoea index (AHI) measured in polysomnographic sleep studies. Data was transmitted daily to a central monitoring centre and analysed in consecutive 2-week blocks. A total of 37 465 nights over 3-24 months was analysed. An AHI of >15/h was considered clinically significant. Short- and long-term (total study) patterns of SDB presence and severity were compared. Long-term analysis (total study) showed that significant sleep-disordered breathing was common: paroxysmal in many (38%) and persistent (18%) in others. Short-term analysis showed that the severity of sleep apnoea was highly variable with 48% fluctuating between mild and moderate/severe during the study. In contrast to standard sleep studies a non-contact biosensor combined with remote monitoring can detect short- and long-term trends in SDB in clinically stable HF patients, which may be an index of HF status over time and is potentially a therapeutic target.

  16. 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; ...

  17. Association of heart rate variability and inflammatory response in patients with cardiovascular diseases: current strengths and limitations

    PubMed Central

    Papaioannou, Vasilios; Pneumatikos, Ioannis; Maglaveras, Nikos

    2013-01-01

    Many experimental and clinical studies have confirmed a continuous cross-talk between both sympathetic and parasympathetic branches of autonomic nervous system and inflammatory response, in different clinical scenarios. In cardiovascular diseases, inflammation has been proven to play a pivotal role in disease progression, pathogenesis and resolution. A few clinical studies have assessed the possible inter-relation between neuro-autonomic output, estimated with heart rate variability analysis, which is the variability of R-R in the electrocardiogram, and different inflammatory biomarkers, in patients suffering from stable or unstable coronary artery disease (CAD) and heart failure. Moreover, different indices derived from heart rate signals' processing, have been proven to correlate strongly with severity of heart disease and predict final outcome. In this review article we will summarize major findings from different investigators, evaluating neuro-immunological interactions through heart rate variability analysis, in different groups of cardiovascular patients. We suggest that markers originating from variability analysis of heart rate signals seem to be related to inflammatory biomarkers. However, a lot of open questions remain to be addressed, regarding the existence of a true association between heart rate variability and autonomic nervous system output or its adoption for risk stratification and therapeutic monitoring at the bedside. Finally, potential therapeutic implications will be discussed, leading to autonomic balance restoration in relation with inflammatory control. PMID:23847549

  18. Medical Issues: Breathing

    MedlinePlus

    ... support & care > living with sma > medical issues > breathing Breathing Breathing problems are the most common cause of illness for children with SMA. Breathing Risks In healthy individuals, the muscles between the ...

  19. Relationship between cardiovascular health score and year-to-year blood pressure variability in China: a prospective cohort study

    PubMed Central

    An, Shasha; Bao, Minghui; Wang, Yang; Li, Zhifang; Zhang, Wenyan; Chen, Shuohua; Li, Junjuan; Yang, Xinchun; Wu, Shouling; Cai, Jun

    2015-01-01

    Objectives On the basis of cardiovascular health factors and behaviours, the American Heart Association proposed the Cardiovascular Health Score (CHS). It has been widely used to estimate the cardiovascular health status of individuals. The aim of this study was to investigate the relationship between CHS and year-to-year blood pressure variability (BPV). Design Prospective cohort study. Settings We stratified participants into two groups by gender: first group, female group; second group, male group. The relationship between CHS and year-to-year blood pressure variability were analysed. Participants A total of 41 613 individuals met the inclusion criteria (no history of stroke, transient ischaemic attack, myocardial infarction, malignant tumour or atrial fibrillation) and had complete blood pressure data. Results The coefficient of the variation of systolic blood pressure (SCV) was 8.33% in the total population and 8.68% and 8.22% in female and male groups, respectively (p<0.05). Multivariable linear regression analysis revealed that higher CHS was inversely associated with increasing year-to-year BPV, which persisted after adjusting for baseline systolic blood pressure and other risk factors. Each SD increase in CHS could lead to a 0.016SD decrease in SCV (p<0.05). Conclusions In summary, CHS was inversely related to year-to-year BPV, which suggested that a healthy lifestyle may contribute to better blood pressure management. PMID:26503389

  20. Collection of breath for hydrogen estimation.

    PubMed

    Gardiner, A J; Tarlow, M J; Sutherland, I T; Sammons, H G

    1981-02-01

    The breath hydrogen test is used in gastroenterological investigation, particularly for sugar malabsorption, transit time, and the investigation of small-bowel bacterial overgrowth. Several methods of collecting breath from infants and children for hydrogen assay have been described. Four such techniques (postnasal catheter, nasal prong, Rahn-Otis end-tidal sampler, and modification of a party toy--the 'Wiggins's blowout') were compared with breath collection using the Haldane-Priestley tube. Multiple sampling of breath from 3 adults was performed after initial lactulose loads to increase breath hydrogen excretion. The variability between the different assay techniques was less than the inherent variability of repeated breath hydrogen assays using the same technique. Each technique is therefore adequate for breath hydrogen collection; we recommend the Rahn-Otis end-tidal sampler in young infants and children, and the Haldane-Priestley tube in older children, since these were most acceptable to the children and their parents.

  1. 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.

  2. Developmental change and intraindividual variability: relating cognitive aging to cognitive plasticity, cardiovascular lability, and emotional diversity.

    PubMed

    Ram, Nilam; Gerstorf, Denis; Lindenberger, Ulman; Smith, Jacqui

    2011-06-01

    Repeated assessments obtained over years can be used to measure individuals' developmental change, whereas repeated assessments obtained over a few weeks can be used to measure individuals' dynamic characteristics. Using data from a burst of measurement embedded in the Berlin Aging Study (BASE; Baltes & Mayer, 1999), we illustrate and examine how long-term changes in cognitive ability are related to short-term changes in cognitive performance, cardiovascular function, and emotional experience. Our findings suggest that "better" cognitive aging over approximately 13 years was associated with greater cognitive plasticity, less cardiovascular lability, and less emotional diversity over approximately 2 weeks at age 90 years. The study highlights the potential benefits of multi-time scale longitudinal designs for the study of individual function and development.

  3. 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

  4. 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.

  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. Association between RR interval and high-frequency heart rate variability acquired during short-term, resting recordings with free and paced breathing.

    PubMed

    Sandercock, Gavin; Gladwell, Valerie; Dawson, Samantha; Nunan, David; Brodie, David; Beneke, Ralph

    2008-07-01

    High-frequency (HF) oscillations in RR interval from 0.15-0.40 Hz are widely accepted as a measure of cardiac vagal outflow but the HF/RR relationship appears complex, particularly with longer RR intervals. The aim of this study was to evaluate the HF/RR interval relationship during free and paced breathing. HF power and mean RR interval length were recorded in 150 men and 120 women (mean age 34.5 +/- 11.4) during 5 min of supine rest with either free or paced (12 cycles min(-1)) breathing. Linear and quadratic models were used to assess the relationship between RR interval and the natural logarithm of HF power (lnHF). The RR interval length at which there was no further increase in lnHF was determined as the deflection point. ANCOVA was used to determine differences in the linear regression slopes for lnHF/RR with paced or free breathing. With free breathing (n = 131), the adjusted R(2) was similar between linear (15.3%) and quadratic (17.5%) fits and saturation of lnHF occurred within the recorded RR interval range (1326 ms). With paced breathing (n = 139), adjusted R(2) values were again similar between linear (22.4%) and quadratic (23.2%) fits. The deflection point was outside the range of recorded RR intervals at 1458 ms. ANCOVA showed a significant difference in the slope of the lnHF/RR regression lines between free and paced breathing. The lnHF/RR relationship is weaker when derived from between-subject recordings than from repeated within-subject samples. lnHF/RR showed evidence of saturation at approximately 45 bpm with free breathing. With paced breathing, a deflection in lnHF was found outside the recorded RR interval range ( approximately 41 bpm). Paced breathing creates a stronger lnHF/RR relationship. The slope of the lnHF/RR regression line with paced breathing is significantly different from that observed with free breathing. It appears that lnHF is a valid index of vagal outflow, except in subjects with very low heart rates. Paced breathing data

  7. Decomposing the transfer entropy to quantify lag-specific Granger causality in cardiovascular variability.

    PubMed

    Faes, Luca; Nollo, Giandomenico

    2013-01-01

    We present a modification of the well known transfer entropy (TE) which makes it able to detect, besides the direction and strength of the information transfer between coupled processes, its exact timing. The approach follows a decomposition strategy which identifies--according to a lag-specific formulation of the concept of Granger causality--the set of time delays carrying significant information, and then assigns to each of these delays an amount of information transfer such that the total contribution yields the overall TE. We propose also a procedure for the practical estimation from time series data of the relevant delays and lag-specific TE in both bivariate and multivariate settings. The proposed approach is tested in simulations and in real cardiovascular time series, showing the feasibility of lag-specific TE estimation, the ability to reflect expected mechanisms of cardiovascular regulation, and the necessity of using the multivariate TE to properly assess time-lagged information transfer in the presence of multiple interacting systems.

  8. Breathing and Relaxation

    MedlinePlus

    ... Home Health Insights Stress & Relaxation Breathing and Relaxation Breathing and Relaxation Make an Appointment Ask a Question ... level is often dependent on his or her breathing pattern. Therefore, people with chronic lung conditions may ...

  9. Deep breathing after surgery

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000440.htm Deep breathing after surgery To use the sharing features on ... way to do so is by doing deep breathing exercises. Deep breathing keeps your lungs well-inflated ...

  10. Rapid shallow breathing

    MedlinePlus

    Tachypnea; Breathing - rapid and shallow; Fast shallow breathing; Respiratory rate - rapid and shallow ... Shallow, rapid breathing has many possible medical causes, including: Asthma Blood clot in an artery in the lung Choking Chronic obstructive ...

  11. 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.

  12. Cardiovascular Variability Analysis and Baroreflex Estimation in Patients with Type 2 Diabetes in Absence of Any Manifest Neuropathy

    PubMed Central

    de Moura-Tonello, Sílvia Cristina Garcia; Porta, Alberto; Marchi, Andrea; de Almeida Fagundes, Alessandra; Francisco, Cristina de Oliveira; Rehder-Santos, Patrícia; Milan-Mattos, Juliana Cristina; Simões, Rodrigo Polaquini; Gois, Mariana de Oliveira; Catai, Aparecida Maria

    2016-01-01

    Introduction Indexes derived from spontaneous heart period (HP) and systolic arterial pressure (SAP) fluctuations can detect autonomic dysfunction in individuals with type 2 diabetes mellitus (DM) associated to cardiovascular autonomic neuropathy (CAN) or other neuropathies. It is unknown whether HP and SAP variability indexes are sensitive enough to detect the autonomic dysfunction in DM patients without CAN and other neuropathies. Methods We evaluated 68 males aged between 40 and 65 years. The group was composed by DM type 2 DM with no manifest neuropathy (n = 34) and healthy (H) subjects (n = 34). The protocol consisted of 15 minutes of recording of HP and SAP variabilities at rest in supine position (REST) and after active standing (STAND). The HP power in the high frequency band (HF, from 0.15 to 0.5 Hz), the SAP power in the low frequency band (LF, from 0.04 to 0.15 Hz) and BRS estimated via spectral approach and sequence method were computed. Results The HF power of HP was lower in DM patients than in H subjects, while the two groups exhibited comparable HF power of HP during STAND. The LF power of SAP was similar in DM and H groups at REST and increased during STAND in both groups. BRSs estimated in the HF band and via baroreflex sequence method were lower in DM than in H and they decreased further during STAND in both populations. Conclusion Results suggest that vagal control of heart rate and cardiac baroreflex control was impaired in type 2 DM, while sympathetic control directed to vessels, sympathetic and baroreflex response to STAND were preserved. Cardiovascular variability indexes are sensitive enough to typify the early, peculiar signs of autonomic dysfunction in type-2 DM patients well before CAN becomes manifest. PMID:26987126

  13. 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.

  14. P-glycoprotein: a focus on characterizing variability in cardiovascular pharmacotherapeutics.

    PubMed

    Al-Khazaali, Ali; Arora, Rohit

    2014-01-01

    According to the report of Agency for Healthcare Research and Quality in 2008, drug-related adverse outcomes exceed 2.7 million events per year. Therefore, it is requisite to understand the etiologies of those unpleasant outcomes. Polypharmacy especially in the elderly is considered one of the major sources of drug-related side effects. The drug-related membrane transporters play an indispensable role in the pharmacokinetics, safety, and efficacy of the drugs. P-glycoprotein, also known as P-gp, is considered one of the core drug transporters in vivo. Since its discovery in 1976, P-gp gained a tremendous attention of researchers and clinicians. The core objective of this review is to highlight the clinical correlation between the P-gp and a number of cardiovascular drugs and to address the drug-drug interaction in case of using those cardiovascular drugs with P-gp-related drugs whether substrates, inhibitors, or inducers. Bearing in mind that P-gp is found in liver and intestine, as well as cytochrome P450, a strong association between the 2 systems is expected. Yet, plenty of the drugs that can behave as substrates to P-gp can act as substrates to CYP450 too. Consequently, probable drug-drug interaction can occur between drugs that work on both systems. In other words, whenever these classes of medications prescribed together cautious monitoring of drug's level and eventually dose adjustment might be necessary to avoid drug-drug interactions, failure of therapy, or drug toxicity; especially with the use of drugs that possess narrow therapeutic index like digoxin.

  15. Effect of meal content on heart rate variability and cardiovascular reactivity to mental stress

    PubMed Central

    Sauder, Katherine A.; Johnston, Elyse R.; Skulas-Ray, Ann C.; Campbell, Tavis S.; West, Sheila G.

    2012-01-01

    Little is known about transient effects of foods and nutrients on reactivity to mental stress. In a randomized crossover study of healthy adults (n = 20), we measured heart rate variability (respiratory sinus arrhythmia), blood pressure, and other hemodynamic variables after three test meals varying in type and amount of fat. Measurements were collected at rest and during speech and cold pressor tasks. There were significant post-meal changes in resting diastolic blood pressure (−4%), cardiac output (+18%), total peripheral resistance (−17%), and interleukin-6 (−27%). Heart rate variability and hemodynamic reactivity to stress was not affected by meal content. We recommend that future studies control for time since last meal and continue to examine effects of meal content on heart rate variability. PMID:22236402

  16. Maximal-radius multiscale entropy of cardiovascular variability: a promising biomarker of pathological mood states in bipolar disorders.

    PubMed

    Valenza, Gaetano; Nardelli, Mimma; Bertschy, Gilles; Lanatà, Antonio; Barbieri, Riccardo; Scilingo, Enzo Pasquale

    2014-01-01

    Complexity measures from Multiscale Entropy (MSE) analysis of cardiovascular variability may provide potential biomarkers of pathological mental states such as major depression. To this extent, in this study we investigate whether complexity of Heart Rate Variability (HRV) is also affected in mental disorders such as bipolar disorders (BD). As part of the European project PSYCHE, eight BD patients experiencing multiple pathological mood states among depression, hypomania, and euthymia (i.e., good affective balance) underwent long-term night recordings through a comfortable sensing t-shirt with integrated fabric electrodes and sensors. Standard radius, i.e., 20% of the HRV standard deviation, and a maximal-radius choice for the sample entropy estimation were compared along with a further multiscale Renyi Entropy analysis. We found that, despite the inter-subject variability, the maximal-radius MSE analysis is able to discern the considered pathological mental states of BD. As the current clinical practice in diagnosing BD is only based on verbal interviews and scores from specific questionnaires, these findings provide evidence on the possibility of using heartbeat complexity as the basis of novel clinical biomarkers of mental disorders.

  17. 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.

  18. Ecological sounds affect breath duration more than artificial sounds.

    PubMed

    Murgia, Mauro; Santoro, Ilaria; Tamburini, Giorgia; Prpic, Valter; Sors, Fabrizio; Galmonte, Alessandra; Agostini, Tiziano

    2016-01-01

    Previous research has demonstrated that auditory rhythms affect both movement and physiological functions. We hypothesized that the ecological sounds of human breathing can affect breathing more than artificial sounds of breathing, varying in tones for inspiration and expiration. To address this question, we monitored the breath duration of participants exposed to three conditions: (a) ecological sounds of breathing, (b) artificial sounds of breathing having equal temporal features as the ecological sounds, (c) no sounds (control). We found that participants' breath duration variability was reduced in the ecological sound condition, more than in the artificial sound condition. We suggest that ecological sounds captured the timing of breathing better than artificial sounds, guiding as a consequence participants' breathing. We interpreted our results according to the Theory of Event Coding, providing further support to its validity, and suggesting its possible extension in the domain of physiological functions which are both consciously and unconsciously controlled.

  19. Breathing exercises: influence on breathing patterns and thoracoabdominal motion in healthy subjects

    PubMed Central

    Vieira, Danielle S. R.; Mendes, Liliane P. S.; Elmiro, Nathália S.; Velloso, Marcelo; Britto, Raquel R.; Parreira, Verônica F.

    2014-01-01

    BACKGROUND: The mechanisms underlying breathing exercises have not been fully elucidated. OBJECTIVES: To evaluate the impact of four on breathing exercises (diaphragmatic breathing, inspiratory sighs, sustained maximal inspiration and intercostal exercise) the on breathing pattern and thoracoabdominal motion in healthy subjects. METHOD: Fifteen subjects of both sexes, aged 23±1.5 years old and with normal pulmonary function tests, participated in the study. The subjects were evaluated using the optoelectronic plethysmography system in a supine position with a trunk inclination of 45° during quiet breathing and the breathing exercises. The order of the breathing exercises was randomized. Statistical analysis was performed by the Friedman test and an ANOVA for repeated measures with one factor (breathing exercises), followed by preplanned contrasts and Bonferroni correction. A p<0.005 value was considered significant. RESULTS: All breathing exercises significantly increased the tidal volume of the chest wall (Vcw) and reduced the respiratory rate (RR) in comparison to quiet breathing. The diaphragmatic breathing exercise was responsible for the lowest Vcw, the lowest contribution of the rib cage, and the highest contribution of the abdomen. The sustained maximal inspiration exercise promoted greater reduction in RR compared to the diaphragmatic and intercostal exercises. Inspiratory sighs and intercostal exercises were responsible for the highest values of minute ventilation. Thoracoabdominal asynchrony variables increased significantly during diaphragmatic breathing. CONCLUSIONS: The results showed that the breathing exercises investigated in this study produced modifications in the breathing pattern (e.g., increase in tidal volume and decrease in RR) as well as in thoracoabdominal motion (e.g., increase in abdominal contribution during diaphragmatic breathing), among others. PMID:25590447

  20. Impact of Glycemic and Blood Pressure Variability on Surrogate Measures of Cardiovascular Outcomes in Type 2 Diabetic Patients

    PubMed Central

    Di Flaviani, Alessandra; Picconi, Fabiana; Di Stefano, Paola; Giordani, Ilaria; Malandrucco, Ilaria; Maggio, Paola; Palazzo, Paola; Sgreccia, Fabrizio; Peraldo, Carlo; Farina, Fabrizio; Frajese, Gaetano; Frontoni, Simona

    2011-01-01

    OBJECTIVE The effect of glycemic variability (GV) on cardiovascular risk has not been fully clarified in type 2 diabetes. We evaluated the effect of GV, blood pressure (BP), and oxidative stress on intima-media thickness (IMT), left ventricular mass index (LVMI), flow-mediated dilation (FMD), and sympathovagal balance (low frequency [LF]/high frequency [HF] ratio) in 26 type 2 diabetic patients (diabetes duration 4.41 ± 4.81 years; HbA1c 6.70 ± 1.25%) receiving diet and/or metformin treatment, with no hypotensive treatment or complications. RESEARCH DESIGN AND METHODS Continuous glucose monitoring (CGM) data were used to calculate mean amplitude of glycemic excursion (MAGE), continuous overall net glycemic action (CONGA)-2, mean blood glucose (MBG), mean postprandial glucose excursion (MPPGE), and incremental area under the curve (IAUC). Blood pressure (BP), circadian rhythm, and urinary 15-F2t-isoprostane (8-iso-prostaglandin F2α [PGF2α]) were also evaluated. Subjects were divided into dipper (D) and nondipper (ND) groups according to ΔBP. RESULTS IMT and LVMI were increased in ND versus D (0.77 ± 0.08 vs. 0.68 ± 0.13 [P = 0.04] and 67 ± 14 vs. 55 ± 11 [P = 0.03], respectively). MBG, MAGE, and IAUC were significantly associated with LF/HF ratio at night (r = 0.50, P = 0.01; r = 0.40, P = 0.04; r = 0.41, P = 0.04, respectively), MPPGE was negatively associated with FMD (r = −0.45, P = 0.02), and CONGA-2 was positively associated with LVMI (r = 0.55, P = 0.006). The Δsystolic BP was negatively associated with IMT (r = −0.43, P = 0.03) and with LVMI (r = −0.52, P = 0.01). Urinary 8-iso-PGF2α was positively associated with LVMI (r = 0.68 P < 0.001). CONCLUSIONS An impaired GV and BP variability is associated with endothelial and cardiovascular damage in short-term diabetic patients with optimal metabolic control. Oxidative stress is the only independent predictor of increased LV mass and correlates with glucose and BP variability. PMID:21610126

  1. Of larks and hearts--morningness/eveningness, heart rate variability and cardiovascular stress response at different times of day.

    PubMed

    Roeser, Karolin; Obergfell, Friederike; Meule, Adrian; Vögele, Claus; Schlarb, Angelika A; Kübler, Andrea

    2012-05-15

    Inter-individual differences in the circadian period of physical and mental functions can be described on the dimension of morningness/eveningness. Previous findings support the assumption that eveningness is related to greater impulsivity and susceptibility to stress than morningness. Heart rate variability (HRV) serves as a physiological correlate of self- and emotional regulation and has not yet been investigated in relation to chronotypes. The study explores differences in HRV and other cardiovascular measures in morning- and evening-types at rest and under stress at different times of day (8-11 a.m. or 4-7 p.m.). Students (N=471) were screened for chronotype and n=55 females (27 morning- and 28 evening-types) were recruited for testing. These participants performed a mental arithmetic task while heart rate (HR) and blood pressure (BP) were recorded. Spectral components and a time-domain measure of HRV were calculated on HR data from resting and mental stress periods. Evening-types had significantly higher HR and systolic BP, but lower HRV than morning-types both at baseline and during stress. Stress induced in the evening had a significantly stronger impact on absolute and baseline corrected physiological measures in both chronotypes. The interaction of chronotype and testing time did not reach the level of significance for any of the dependent variables. The enhanced physiological arousal in evening-types might contribute to increased vulnerability to psychological distress. Hence, previous behavioral findings are supported by the physiological data of this study.

  2. 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.

  3. 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.

  4. Assessment of Risk Factor for Cardiovascular Disease Using Heart Rate Variability in Postmenopausal Women: A Comparative Study between Urban and Rural Indian Women

    PubMed Central

    Narayanaswamy, Nikhil; Halahalli, Harsha; Mirajkar, Amrit M.

    2013-01-01

    Cardiovascular diseases are important causes of morbidity and mortality in postmenopausal women. A major determinant of cardiovascular health is the status of autonomic nervous system and assessment of Heart Rate Variability (HRV). Heart Rate Variability is a noninvasive and sensitive technique to evaluate cardiovascular autonomic control. Reduced HRV is an independent risk factor for the development of heart disease. This study evaluated the risk factors for cardiovascular diseases using HRV, between urban and rural Indian postmenopausal women ranging in age from 40 to 75 years. Findings of the analysis of HRV have showed that the total power which reflects overall modulation of cardiac autonomic activity (759 ± 100  versus 444 ± 65), the absolute power of high frequency which is surrogate of cardiovagal activity (247 ± 41  versus 163 ± 45), and low frequency that reflects cardiac sympathetic activity (205 ± 26  versus 127 ± 18) were significantly higher in urban women than that of their rural counterparts. Further, among the anthropometric measures, waist circumference was significantly correlated with indices of HRV. The study concludes that rural Indian women are associated with an additional risk beyond that of ageing and postmenopausal status when compared to the urban women. The higher central obesity could be the contributing factor for developing higher risk for cardiovascular disease among the rural women. PMID:23936672

  5. Minimizing Shortness of Breath

    MedlinePlus

    ... postures and exposure to environmental irritants. Pursed-Lip Breathing One focus of occupational therapy is to teach ... the accessory muscles and manage respiratory symptoms. Monitor Breathing During an activity, it is important to pause ...

  6. Breathing difficulty - lying down

    MedlinePlus

    Waking at night short of breath; Paroxysmal nocturnal dyspnea; PND; Difficulty breathing while lying down; Orthopnea ... obstructive pulmonary disease (COPD) Cor pulmonale Heart failure ... conditions that lead to it) Panic disorder Sleep apnea Snoring

  7. 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.

  8. What Causes Bad Breath?

    MedlinePlus

    ... A Week of Healthy Breakfasts Shyness What Causes Bad Breath? KidsHealth > For Teens > What Causes Bad Breath? A A A en español ¿Qué es lo que provoca el mal aliento? Bad breath, or halitosis , can be a major problem, ...

  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. Cardiovascular autonomic neuropathy in patients with diabetes mellitus.

    PubMed

    Lozano, T; Ena, J

    Cardiovascular autonomic neuropathy associated with diabetes mellitus is caused by an impairment of the autonomic system. The prevalence of this condition ranges from 20% to 65%, depending on the duration of the diabetes mellitus. Clinically, the autonomic function disorder is associated with resting tachycardia, exercise intolerance, orthostatic hypotension, intraoperative cardiovascular instability, silent myocardial ischemia and increased mortality. For the diagnosis, the integrity of the parasympathetic and sympathetic nervous system is assessed. Parasympathetic activity is examined by measuring heart rate variability in response to deep breathing, standing and the Valsalva manoeuvre. Sympathetic integrity is examined by measuring blood pressure in response to standing and isometric exercise. The treatment includes the metabolic control of diabetes mellitus and of the cardiovascular risk factors. Treating symptoms such as orthostatic hypotension requires special attention.

  11. Highly variable expression of virus receptors in the human cardiovascular system. Implications for cardiotropic viral infections and gene therapy.

    PubMed

    Poller, W; Fechner, H; Noutsias, M; Tschoepe, C; Schultheiss, H-P

    2002-12-01

    analysis of the cardiovascular expression patterns of receptors for other potentially cardiotropic viruses (CMV, EBV, HIV, HHV-6, Parvo-B19, etc.) should lead to a better understanding of individual risk factors for viral heart diseases and of their highly variable clinical courses, and offer new therapeutic options.

  12. 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.

  13. Episodic breathing in alligators: role of sensory feedback.

    PubMed

    Douse, M A; Mitchell, G S

    1992-01-01

    The episodic breathing pattern in many reptiles consists of two or more clustered breaths separated by variable non-ventilatory periods. This pattern is commonly postulated to result from oscillations in lung and/or blood PO2 or PCO2 via chemoreceptor feedback. We tested this hypothesis by monitoring breathing pattern in: (1) awake, undisturbed alligators and (2) sedated alligators (approx. 25 mg/kg pentobarbital, i.p.; 3 days prior to data collection). In sedated alligators, measurements were made: (1) before and after bilateral cervical vagotomy, a procedure that removes peripheral arterial chemoreceptors, CO2-sensitive intrapulmonary chemoreceptors and pulmonary stretch receptors (n = 6); and (2) during unidirectional ventilation (UDV) at high flow rates (greater than 2 L/min), thereby minimizing oscillations in lung and blood PO2 and PCO2 (n = 6). Measurements on sedated alligators were made at 30 and 20 degrees C in each of these conditions. In awake, undisturbed alligators, breathing was typically episodic with 2-7 breaths/cluster, although the pattern was easily altered (increased breaths/cluster) by even seemingly minor disturbances. In sedated alligators, episodic breathing was still evident after vagotomy, but only at increased inspired CO2; at 5% CO2 four of six alligators exhibited episodic breathing consisting of 2-3 breaths/cluster interspersed with occasional single breaths. An episodic breathing pattern was also evident during UDV; at low levels of CO2, 2-4 breaths/cluster interspersed with occasional single breaths were evident in four alligators, while two had 6-8 breaths/cluster. Increasing CO2 in the UDV gas stream generally increased the number of breaths/cluster. After vagotomy, all six alligators could manifest an episodic breathing pattern during UDV in at least one CO2 condition (greater than 2 breaths/cluster interspersed with occasional single breaths). The episodic breathing pattern was very labile, sometimes changing to single breaths

  14. Fetal cardiac autonomic control during breathing and non-breathing epochs: the effect of maternal exercise.

    PubMed

    Gustafson, Kathleen M; May, Linda E; Yeh, Hung-wen; Million, Stephanie K; Allen, John J B

    2012-07-01

    We explored whether maternal exercise during pregnancy moderates the effect of fetal breathing movements on fetal cardiac autonomic control assessed by metrics of heart rate (HR) and heart rate variability (HRV). Thirty women were assigned to Exercise or Control group (n=15/group) based on the modifiable physical activity questionnaire (MPAQ). Magnetocardiograms (MCG) were recorded using a dedicated fetal biomagnetometer. Periods of fetal breathing activity and apnea were identified using the fetal diaphragmatic magnetomyogram (dMMG) as a marker. MCG R-waves were marked. Metrics of fetal HR and HRV were compared using 1 breathing and 1 apneic epoch/fetus. The main effects of group (Exercise vs. Control) and condition (Apnea vs. Breathing) and their interactions were explored. Fetal breathing resulted in significantly lower fetal HR and higher vagally-mediated HRV. Maternal exercise resulted in significantly lower fetal HR, higher total HRV and vagally-mediated HRV with no difference in frequency band ratios. Significant interactions between maternal exercise and fetal breathing were found for metrics summarizing total HRV and a parasympathetic metric. Post hoc comparison showed no group difference during fetal apnea. Fetal breathing was associated with a loss of Total HRV in the Control group and no difference in the Exercise group. Both groups show enhanced vagal function during fetal breathing; greater in the Exercise group. During in utero breathing movements, the fetus of the exercising mother has enhanced cardiac autonomic function that may give the offspring an adaptive advantage.

  15. Control of breathing in the echidna (Tachyglossus aculeatus) during hibernation.

    PubMed

    Nicol, Stewart; Andersen, Niels A

    2003-12-01

    Resting non-hibernating echidnas are characterised by low metabolic rates, but also have a very low respiratory frequency and a variable respiratory minute volume, often resulting in low levels of arterial O(2) and high CO(2). As the echidna lies at one physiological extreme among the hibernators, in terms of its large size and low metabolism and ventilatory requirement when not hibernating, a study of control of breathing during hibernation in echidnas should provide a useful test of the generality of various models. We used non-invasive techniques to study breathing patterns and the control of ventilation in 6 echidnas. Hibernating echidnas (T(b) range 7-10 degrees C) showed episodic breathing with bursts of breaths (average 36+/-16 breaths in 24+/-5 min) followed by a period of apnea (76+/-17 min) then a series (8+/-4) of slow breaths at 14+/-1 min intervals leading up to the next burst. Increasing CO(2) levels in the inspired air increased the number of breaths in a burst, eventually leading to continuous breathing. Inter burst breaths were controlled by O(2): hypoxia increased inter burst breaths, and decreased burst length, while hyperoxia abolished inter burst breaths and increased the apneic period. Overall, while CO(2) was a strong respiratory stimulus in hibernating echidnas, O(2) had little effect on total ventilation, but did have a strong effect on the breathing pattern.

  16. Effects of acepromazine and trazodone on anesthetic induction dose of propofol and cardiovascular variables in dogs undergoing general anesthesia for orthopedic surgery.

    PubMed

    Murphy, Lindsey A; Barletta, Michele; Graham, Lynelle F; Reichl, Lorna J; Duxbury, Margaret M; Quandt, Jane E

    2017-02-15

    OBJECTIVE To compare the doses of propofol required to induce general anesthesia in dogs premedicated with acepromazine maleate or trazodone hydrochloride and compare the effects of these premedicants on cardiovascular variables in dogs anesthetized for orthopedic surgery. DESIGN Prospective, randomized study. ANIMALS 30 systemically healthy client-owned dogs. PROCEDURES 15 dogs received acepromazine (0.01 to 0.03 mg/kg [0.005 to 0.014 mg/lb], IM) 30 minutes before anesthetic induction and 15 received trazodone (5 mg/kg [2.27 mg/lb] for patients > 10 kg or 7 mg/kg [3.18 mg/lb] for patients ≤ 10 kg, PO) 2 hours before induction. Both groups received morphine sulfate (1 mg/kg [0.45 mg/lb], IM) 30 minutes before induction. Anesthesia was induced with propofol (4 to 6 mg/kg [1.82 to 2.73 mg/lb], IV, to effect) and maintained with isoflurane or sevoflurane in oxygen. Bupivacaine (0.5 mg/kg [0.227 mg/lb]) and morphine (0.1 mg/kg [0.045 mg/lb]) were administered epidurally. Dogs underwent tibial plateau leveling osteotomy (n = 22) or tibial tuberosity advancement (8) and were monitored throughout anesthesia. Propofol induction doses and cardiovascular variables (heart rate and systemic, mean, and diastolic arterial blood pressures) were compared between groups. RESULTS The mean dose of propofol required for anesthetic induction and all cardiovascular variables evaluated did not differ between groups. Intraoperative hypotension developed in 6 and 5 dogs of the acepromazine and trazodone groups, respectively; bradycardia requiring intervention developed in 3 dogs/group. One dog that received trazodone had priapism 24 hours later and was treated successfully. No other adverse effects were reported. CONCLUSIONS AND CLINICAL RELEVANCE At the described dosages, cardiovascular effects of trazodone were similar to those of acepromazine in healthy dogs undergoing anesthesia for orthopedic surgery.

  17. Effects of respiratory time ratio on heart rate variability and spontaneous baroreflex sensitivity.

    PubMed

    Wang, Yong-Ping; Kuo, Terry B J; Lai, Chun-Ting; Chu, Jui-Wen; Yang, Cheryl C H

    2013-12-01

    Paced breathing is a frequently performed technique for cardiovascular autonomic studies. The relative timing of inspiration and expiration during paced breathing, however, is not consistent. We, therefore, examined whether indexes of heart rate variability and spontaneous baroreflex sensitivity would be affected by the respiratory time ratio that is set. We studied 14 healthy young adults who controlled their breathing rates to either 0.1 or 0.25 Hz in the supine and sitting positions. Four different inspiratory-to-expiratory time ratios (I/E) (uncontrolled, 1:1, 1:2, and 1:3) were examined for each condition in a randomized order. The results showed spectral indexes of heart rate variability and spontaneous baroreflex sensitivity were not influenced by the I/E that was set during paced breathing under supine and sitting positions. Porta's and Guzik's indexes of heart rate asymmetry were also not different at various I/E during 0.1-Hz breathing, but had larger values at 1:1 during 0.25-Hz breathing, although significant change was found in the sitting position only. At the same time, Porta's and Guzik's indexes obtained during 0.1-Hz breathing were greater than during 0.25-Hz breathing in both positions. The authors suggest that setting the I/E during paced breathing is not necessary when measuring spectral indexes of heart rate variability and spontaneous baroreflex sensitivity under the conditions used in this study. The necessity of paced breathing for the measurement of heart rate asymmetry, however, requires further investigation.

  18. Cardiovascular pharmacogenetics.

    PubMed

    Myburgh, Renier; Hochfeld, Warren E; Dodgen, Tyren M; Ker, James; Pepper, Michael S

    2012-03-01

    Human genetic variation in the form of single nucleotide polymorphisms as well as more complex structural variations such as insertions, deletions and copy number variants, is partially responsible for the clinical variation seen in response to pharmacotherapeutic drugs. This affects the likelihood of experiencing adverse drug reactions and also of achieving therapeutic success. In this paper, we review key studies in cardiovascular pharmacogenetics that reveal genetic variations underlying the outcomes of drug treatment in cardiovascular disease. Examples of genetic associations with drug efficacy and toxicity are described, including the roles of genetic variability in pharmacokinetics (e.g. drug metabolizing enzymes) and pharmacodynamics (e.g. drug targets). These findings have functional implications that could lead to the development of genetic tests aimed at minimizing drug toxicity and optimizing drug efficacy in cardiovascular medicine.

  19. Information dynamics in cardiorespiratory analyses: application to controlled breathing.

    PubMed

    Widjaja, Devy; Faes, Luca; Montalto, Alessandro; Van Diest, Ilse; Marinazzo, Daniele; Van Huffel, Sabine

    2014-01-01

    Voluntary adjustment of the breathing pattern is widely used to deal with stress-related conditions. In this study, effects of slow and fast breathing with a low and high inspiratory to expiratory time on heart rate variability (HRV) are evaluated by means of information dynamics. Information transfer is quantified both as the traditional transfer entropy as well as the cross entropy, where the latter does not condition on the past of HRV, thereby taking the highly unidirectional relation between respiration and heart rate into account. The results show that the cross entropy is more suited to quantify cardiorespiratory information transfer as this measure increases during slow breathing, indicating the increased cardiorespiratory coupling and suggesting the shift towards vagal activation during slow breathing. Additionally we found that controlled breathing, either slow or fast, results as well in an increase in cardiorespiratory coupling, compared to spontaneous breathing, which demonstrates the beneficial effects of instructed breathing.

  20. Drinking influences exhaled breath condensate acidity.

    PubMed

    Kullmann, Tamás; Barta, Imre; Antus, Balázs; Horváth, Ildikó

    2008-01-01

    Exhaled breath condensate analysis is a developing method for investigating airway pathology. Impact of food and drink on breath condensate composition has not been systematically addressed. The aim of the study was to follow exhaled breath condensate pH after drinking an acidic and a neutral beverage. Breath condensate, capillary blood, and urine of 12 healthy volunteers were collected before and after drinking either 1 l of coke or 1 l of mineral water. The pH of each sample was determined with a blood gas analyzer. The mean difference between the pH of two breath condensate samples collected within 15 min before drinking was 0.13+/-0.03. Condensate pH decreased significantly from 6.29+/-0.02 to 6.24+/-0.02 (p<0.03) after drinking coke and from 6.37+/-0.03 to 6.22+/-0.04 (p<0.003) after drinking water. Drinking coke induced significant changes in blood and urine pH as well. Drinking influences exhaled breath condensate composition and may contribute to the variability of exhaled breath condensate pH.

  1. 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.

  2. Rate of change in adiposity and its relationship to concomitant changes in cardiovascular risk variables among biracial (black-white) children and young adults: The Bogalusa Heart Study.

    PubMed

    Srinivasan, S R; Myers, L; Berenson, G S

    2001-03-01

    To assess the annual rate of change in adiposity and its relationship to concomitant changes in cardiovascular risk variables during childhood and young adulthood, serial data on black and white children (n = 3,459; initial and follow-up mean age, 8.1 and 14.4 years) and young adults (n = 1,263; initial and follow-up mean age, 22.5 and 30.9 years) enrolled in the Bogalusa Heart Study were examined. Body mass index (BMI) and sum of subscapular and triceps skinfolds were used as indicators of adiposity. In addition, measurements were made of systolic and diastolic blood pressure and fasting levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, insulin, and glucose. Annualized rate of change for each variable was estimated. The rate of increase in adiposity was significantly more pronounced during childhood versus adulthood. Race difference (blacks > whites) in the rate of increase in adiposity was seen only among females. Females, black females in particular, displayed greater rate of increase in adiposity than males. In a multivariate analysis, the rate of increase in adiposity was related independently of baseline age and baseline adiposity to adverse changes in measured cardiovascular risk variables, except glucose. Many of these associations were modulated significantly by race, sex, and age group. The impact was relatively greater for blood pressure and LDL cholesterol in adults and for triglycerides in children. The changes in blood pressure, LDL cholesterol, and HDL cholesterol were greater in whites, while the rate of increase in insulin was greater in blacks. Females displayed greater changes in blood pressure, HDL cholesterol, and insulin. On the other hand, the rate of increase in triglycerides was greater in males. These results indicate that increases in adiposity regardless of initial status of body fatness alter cardiovascular risk variables towards increased risk beginning in childhood, and

  3. 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.

  4. Breathing-metabolic simulator

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

    Breathing-metabolic simulator was developed to be used for evaluation of life support equipment. Apparatus simulates human breathing rate and controls temperature and humidity of exhaled air as well as its chemical composition. All functions are designed to correspond to various degrees of human response.

  5. What Controls Your Breathing?

    MedlinePlus

    ... Explore How the Lungs Work What Are... The Respiratory System What Happens When You Breathe What Controls Your Breathing Lung Diseases & Conditions Clinical Trials Links Related Topics Asthma Bronchitis COPD How the Heart Works Respiratory Failure Send a link to NHLBI to someone ...

  6. Shortness of Breath

    MedlinePlus

    Symptoms Shortness of breath By Mayo Clinic Staff Few sensations are as frightening as not being able to get enough air. Shortness of breath — known medically as dyspnea — is often described as an intense tightening in the chest, air hunger or a ...

  7. Sleep Disordered Breathing and Hypertension: Does Self-Reported Sleepiness Modify the Association?

    PubMed Central

    Kapur, Vishesh K.; Resnick, Helaine E.; Gottlieb, Daniel J.

    2008-01-01

    Study Objectives: Epidemiologic studies that demonstrate increased risk of hypertension in persons with sleep disordered breathing indicate that only a minority of these persons report significant subjective sleepiness. Studies also suggest that presence of self-reported sleepiness may identify a subset of persons with sleep disordered breathing who are at greatest risk of cardiovascular sequelae, including hypertension. We explore whether self-reported sleepiness modifies the relationship between sleep disordered breathing and prevalent hypertension. Design: Cross-sectional Setting: Multicenter study Participants: 6046 subjects from the Sleep Heart Health Study Measurements: Polysomnography, systolic and diastolic blood pressure, antihypertensive medication use, questionnaire determined excessive sleepiness and Epworth Sleepiness Scale, and covariates. Results: The odds of hypertension at higher apnea hypopnea index categories were larger in participants identified as sleepy based on responses to a frequency of sleepiness question or the Epworth score. For example, for those with AHI ≥30 compared to AHI <1.5, the adjusted odds ratio for hypertension was 2.83 (1.33–6.04) among those reporting sleepiness ≥5 days per month, but only 1.22 (0.89–1.68) among those reporting less frequent daytime sleepiness. In adjusted logistic regression models, there was statistical evidence for effect modification by frequency of sleepiness (P = 0.033) of the association between apnea hypopnea index and hypertension. In adjusted models that included the Epworth score as a continuous variable, the interaction term fell slightly short of statistical significance (β = 0.010, P = 0.07). Conclusion: This study finds that the association of sleep disordered breathing with hypertension is stronger in individuals who report daytime sleepiness than in those who do not. Citation: Kapur VK; Resnick HE; Gottlieb DJ. Sleep disordered breathing and hypertension: does self

  8. Heart rate variability shows different cardiovascular modulation in Parkinson's disease patients with tremor dominant subtype compared to those with akinetic rigid dominant subtype.

    PubMed

    Solla, Paolo; Cadeddu, Christian; Cannas, Antonino; Deidda, Martino; Mura, Nicola; Mercuro, Giuseppe; Marrosu, Francesco

    2015-10-01

    Parkinson's disease (PD) can present with different motor subtypes depending on the predominant symptoms (tremor or rigidity/bradykinesia). Slower disease progression and less cognitive decline are observed in tremor-dominant patients compared to those with akinetic-rigid subtype. Autonomic cardiovascular disorders have been described in parkinsonian patients, although the definite correlations with different subtypes of PD are not clear. In this context, heart rate variability (HRV) analysis represents a non-invasive and established tool in assessing cardiovascular autonomic modulation. We investigate cardiovascular autonomic modulation in PD patients with tremor dominant subtype in comparison to akinetic rigid dominant subtype subjects using HRV analysis. Twenty-eight PD patients (17 with tremor dominant subtype and 11 with akinetic rigid dominant subtype) were enrolled and compared to 17 age and sex-matched healthy controls. HRV was analyzed in time- and frequency-domains. Low-frequency (LF) values were significantly lower in the akinetic rigid dominant subtype than in the tremor dominant group [LF 41.4 ± 13.6 vs 55.5 ± 11.6 (p < 0.007)] indicating that the disease led to a more evident impairment of the baroreflex modulation of the autonomic outflow mediated by both sympathetic and parasympathetic systems in the first class of patients. These findings support the biological relevance of clinical subtypes supporting the idea of a different pathophysiological process between these subtypes. These differences also suggest that different subtypes may also result in different responses to therapy or in the possible development of cardiovascular side effects of dopaminergic drugs in these different populations.

  9. [Cardiovascular pharmacogenomics].

    PubMed

    Scibona, Paula; Angriman, Federico; Simonovich, Ventura; Heller, Martina M; Belloso, Waldo H

    2014-01-01

    Cardiovascular disease remains a major cause of morbidity and mortality worldwide. Current medical practice takes into account information based on population studies and benefits observed in large populations or cohorts. However, individual patients present great differences in both toxicity and clinical efficacy that can be explained by variations in adherence, unknown drug to drug interactions and genetic variability. The latter seems to explain from 20% up to 95% of patient to patient variability. Treating patients with cardiovascular disorders faces the clinician with the challenge to include genomic analysis into daily practice. There are several examples within cardiovascular disease of treatments that can vary in toxicity or clinical usefulness based on genetic changes. One of the main factors affecting the efficacy of Clopidogrel is the phenotype associated with polymorphisms in the gene CYP 2C9. Furthermore, regarding oral anticoagulants, changes in CYP2C9 and VKORC1 play an important role in changing the clinical response to anticoagulation. When analyzing statin treatment, one of their main toxicities (myopathy) can be predicted by the SLCO1B1 polymorphism. The potential for prediction of toxicity and clinical efficacy from the use of genetic analysis warrants further studies aiming towards its inclusion in daily clinical practice.

  10. 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

  11. Breathing metabolic simulator.

    NASA Technical Reports Server (NTRS)

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

    1971-01-01

    Description of a device for simulation of the human breathing and metabolic parameters required for the evaluation of respiratory diagnostic, monitoring, support and resuscitation equipment. The remotely controlled device allows wide variations in breathing rate and depth, breath velocity contour, oxygen uptake and carbon dioxide release to simulate conditions from sleep to hard work, with respiration exchange ratios ranging from hypoventilation to hyperventilation. It also reduces the cost of prolonged testing when simulation chambers with human subjects require three shifts of crews and standby physicians. Several block diagrams of the device and subsystems are given.

  12. 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

  13. Pulse pressure variation to predict fluid responsiveness in spontaneously breathing patients: tidal vs. forced inspiratory breathing.

    PubMed

    Hong, D M; Lee, J M; Seo, J H; Min, J J; Jeon, Y; Bahk, J H

    2014-07-01

    We evaluated whether pulse pressure variation can predict fluid responsiveness in spontaneously breathing patients. Fifty-nine elective thoracic surgical patients were studied before induction of general anaesthesia. After volume expansion with hydroxyethyl starch 6 ml.kg(-1) , patients were defined as responders by a ≥ 15% increase in the cardiac index. Haemodynamic variables were measured before and after volume expansion and pulse pressure variations were calculated during tidal breathing and during forced inspiratory breathing. Median (IQR [range]) pulse pressure variation during forced inspiratory breathing was significantly higher in responders (n = 29) than in non-responders (n = 30) before volume expansion (18.2 (IQR 14.7-18.2 [9.3-31.3])% vs. 10.1 (IQR 8.3-12.6 [4.8-21.1])%, respectively, p < 0.001). The receiver-operating characteristic curve revealed that pulse pressure variation during forced inspiratory breathing could predict fluid responsiveness (area under the curve 0.910, p < 0.0001). Pulse pressure variation measured during forced inspiratory breathing can be used to guide fluid management in spontaneously breathing patients.

  14. Breath-Holding Spells

    MedlinePlus

    ... cause kids to stop breathing and sometimes lose consciousness for up to a minute. In the most ... pose a choking hazard once your child regains consciousness roll your child over onto his or her ...

  15. Breathing - slowed or stopped

    MedlinePlus

    ... who is not responsive is called cardiac (or cardiopulmonary) arrest. In infants and children, the most common ... brain inflammation and infection that affects vital brain functions) Gastroesophageal reflux (heartburn) Holding one's breath Meningitis (inflammation ...

  16. Breathing difficulties - first aid

    MedlinePlus

    ... the wound. Bandage such wounds at once. A "sucking" chest wound allows air to enter the person's ... things you can do to help prevent breathing problems: If you have a history of severe allergic ...

  17. Shortness of Breath

    MedlinePlus

    ... with blood clots in the legs or pelvis (deep venous thrombosis), debilitating medical conditions, immobility, or inherited ... it hard for a person to take a deep breath, which usually results in retention of carbon ...

  18. 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 ...

  19. Inverse problems in reduced order models of cardiovascular haemodynamics: aspects of data assimilation and heart rate variability.

    PubMed

    Pant, Sanjay; Corsini, Chiara; Baker, Catriona; Hsia, Tain-Yen; Pennati, Giancarlo; Vignon-Clementel, Irene E

    2017-01-01

    Inverse problems in cardiovascular modelling have become increasingly important to assess each patient individually. These problems entail estimation of patient-specific model parameters from uncertain measurements acquired in the clinic. In recent years, the method of data assimilation, especially the unscented Kalman filter, has gained popularity to address computational efficiency and uncertainty consideration in such problems. This work highlights and presents solutions to several challenges of this method pertinent to models of cardiovascular haemodynamics. These include methods to (i) avoid ill-conditioning of the covariance matrix, (ii) handle a variety of measurement types, (iii) include a variety of prior knowledge in the method, and (iv) incorporate measurements acquired at different heart rates, a common situation in the clinic where the patient state differs according to the clinical situation. Results are presented for two patient-specific cases of congenital heart disease. To illustrate and validate data assimilation with measurements at different heart rates, the results are presented on a synthetic dataset and on a patient-specific case with heart valve regurgitation. It is shown that the new method significantly improves the agreement between model predictions and measurements. The developed methods can be readily applied to other pathophysiologies and extended to dynamical systems which exhibit different responses under different sets of known parameters or different sets of inputs (such as forcing/excitation frequencies).

  20. Breath-Holding Spells

    MedlinePlus

    ... Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding Your 1- to 3-Month-Old Feeding Your 4- to 7-Month-Old Feeding Your 8- to 12-Month-Old Feeding Your 1- to 2-Year-Old Breath-Holding ... > For Parents > Breath-Holding Spells Print A A A What's ...

  1. Gaseous contaminant distribution in the breathing zone.

    PubMed

    Ojima, Jun

    2012-01-01

    Conventionally, the "breathing zone" is defined as the zone within a 0.3 m (or 10 inches) radius of a worker's nose and mouth, and it has been generally assumed that a contaminant in the breathing zone is homogeneous and its concentration is equivalent to the concentration inhaled by the worker. However, several studies have mentioned that the concentration is not uniform in the breathing zone when a worker is close to the contaminant source. In order to examine the spatial variability of contaminant concentrations in a worker's breathing zone, comparative measurements of personal exposure were carried out in a laboratory. In experiment, ethanol vapor was released in front of a model worker (human subject and mockup mannequin) and the vapor concentrations were measured at two different sampling points, at the nose and at the chest, in the breathing zone. Then, the effects of the sampling location and the body temperature on the exposure were observed. The ratios of nose concentration to chest concentration for the human subject and the mannequin were 0-0.2 and 0.12, respectively. The exposure level of the mannequin was about 5.5-9.3 times higher than that of the human subject.

  2. 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

  3. The chromogranin A- derived N-terminal peptide vasostatin-I: In vivo effects on cardiovascular variables in the rabbit.

    PubMed

    Roatta, Silvestro; Passatore, Magda; Novello, Matteo; Colombo, Barbara; Dondossola, Eleonora; Mohammed, Mazher; Losano, Gianni; Corti, Angelo; Helle, Karen B

    2011-06-07

    This study is the first to report on vascular effect of the chromogranin A derived Vasostatin-I (CgA(1-76)) in vivo. Cardiovascular parameters were recorded in 29 rabbits with sympathetically decentralized right carotid vascular bed. The recombinant human STA CgA(1-78) (VS-1) was infused at 480 μg/kg over 25 min. Group I was kept awake while groups II-V were anesthetized with Ketamine-xylazine. VS-1 was given alone in groups I-II while in presence of either phentolamine, phentolamine plus propranolol or hexamethonium in groups III-V. Serum VS-1 peaked at 2 μg/ml (200 nM) before onset of vascular effects and declined rapidly to ~200 ng/ml within 30 min. In all groups but III and IV VS-1 induced a brief vasoconstriction, being larger in intact than in sympathetically decentralized beds. The VS-1 induced vasoconstriction was not altered by hexamethonium but was abolished by phentolamine. In presence of the α-adrenergic blocker a long lasting vasodilatation, unaffected by propranolol, was apparent on both innervated and decentralized sides. In conclusion, VS-1 induced an α-adrenoceptor-mediated vasoconstriction presumably brought about by noradrenaline release from sympathetic nerves when infused at a dose giving an initial serum concentration of ~200 nM. This initial vasoconstriction masked a persistent adrenoceptor-independent vasodilatation, consistent with previous reports from in vitro models.

  4. Data interpretation in breath biomarker research: pitfalls and directions.

    PubMed

    Miekisch, Wolfram; Herbig, Jens; Schubert, Jochen K

    2012-09-01

    Most--if not all--potential diagnostic applications in breath research involve different marker concentrations rather than unique breath markers which only occur in the diseased state. Hence, data interpretation is a crucial step in breath analysis. To avoid artificial significance in breath testing every effort should be made to implement method validation, data cross-testing and statistical validation along this process. The most common data analysis related problems can be classified into three groups: confounding variables (CVs), which have a real correlation with both the diseased state and a breath marker but lead to the erroneous conclusion that disease and breath are in a causal relationship; voodoo correlations (VCs), which can be understood as statistically true correlations that arise coincidentally in the vast number of measured variables; and statistical misconceptions in the study design (SMSD). CV: Typical confounding variables are environmental and medical history, host factors such as gender, age, weight, etc and parameters that could affect the quality of breath data such as subject breathing mode, effects of breath sampling and effects of the analytical technique itself. VC: The number of measured variables quickly overwhelms the number of samples that can feasibly be taken. As a consequence, the chances of finding coincidental 'voodoo' correlations grow proportionally. VCs can typically be expected in the following scenarios: insufficient number of patients, (too) many measurement variables, the use of advanced statistical data mining methods, and non-independent data for validation. SMSD: Non-prospective, non-blinded and non-randomized trials, a priori biased study populations or group selection with unrealistically high disease prevalence typically represent misconception of study design. In this paper important data interpretation issues are discussed, common pitfalls are addressed and directions for sound data processing and interpretation

  5. 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

  6. Cerebrovascular and cardiovascular variability interactions investigated through conditional joint transfer entropy in subjects prone to postural syncope.

    PubMed

    Bari, Vlasta; De Maria, Beatrice; Mazzucco, Claudio Enrico; Rossato, Gianluca; Tonon, Davide; Nollo, Giandomenico; Faes, Luca; Porta, Alberto

    2017-02-28

    A model-based conditional transfer entropy approach was exploited to quantify the information transfer in cerebrovascular (CBV) and cardiovascular (CV) systems in subjects prone to develop postural syncope. Spontaneous beat-to-beat variations of mean cerebral blood flow velocity (MCBFV) derived from a transcranial Doppler device, heart period (HP) derived from surface electrocardiogram, mean arterial pressure (MAP) and systolic arterial pressure (SAP) derived from finger plethysmographic arterial pressure device were monitored at rest in supine position (REST) and during 60° head-up tilt (TILT) in 13 individuals (age mean±standard deviation: 28±9 years, min-max range: 18-44 years, 5 males) with a history of recurrent episodes of syncope (SYNC) and in 13 age- and gender-matched controls (NonSYNC). Respiration (R) obtained from a thoracic belt was acquired as well and considered as a conditioning signal in transfer entropy assessment. Synchronous sequences of 250 consecutive MCBFV, HP, MAP, SAP and R values were utilized to estimate the information genuinely transferred from MAP to MCBFV (i.e. disambiguated from R influences) and vice versa. Analogous indexes were computed from SAP to HP and vice versa. Traditional time and frequency domain analyses were carried out as well. SYNC subjects showed an increased genuine information transfer from MAP to MCBFV during TILT, while they did not exhibit the expected rise of the genuine information transfer from SAP to HP. We conclude that SYNC individuals featured an impaired cerebral autoregulation visible during TILT and were unable to activate cardiac baroreflex to cope with the postural challenge. Traditional frequency domain markers based on transfer function modulus, phase and coherence functions were less powerful or less specific in typifying the CBV and CV controls of SYNC individuals. Conditional transfer entropy approach can identify the impairment of CBV and CV controls and provide specific clues to identify

  7. 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.

  8. 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

  9. 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,…

  10. 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.

  11. 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.

  12. The Air We Breathe

    NASA Technical Reports Server (NTRS)

    Davila, Dina

    2010-01-01

    Topics discussed include NASA mission to pioneer the future in space exploration, scientific discovery and aeronautics research; the role of Earth's atmosphere, atmospheric gases, layers of the Earth's atmosphere, ozone layer, air pollution, effects of air pollution on people, the Greenhouse Effect, and breathing on the International Space Station.

  13. 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)

  14. Exercise performance and cardiovascular health variables in 70-year-old male soccer players compared to endurance-trained, strength-trained and untrained age-matched men.

    PubMed

    Randers, Morten Bredsgaard; Andersen, Jesper L; Petersen, Jesper; Sundstrup, Emil; Jakobsen, Markus D; Bangsbo, Jens; Saltin, Bengt; Krustrup, Peter

    2014-01-01

    The aim was to investigate performance variables and indicators of cardiovascular health profile in elderly soccer players (SP, n = 11) compared to endurance-trained (ET, n = 8), strength-trained (ST, n = 7) and untrained (UT, n = 7) age-matched men. The 33 men aged 65-85 years underwent a testing protocol including measurements of cycle performance, maximal oxygen uptake (VO2max) and body composition, and muscle fibre types and capillarisation were determined from m. vastus lateralis biopsy. In SP, time to exhaustion was longer (16.3 ± 2.0 min; P < 0.01) than in UT (+48%) and ST (+41%), but similar to ET (+1%). Fat percentage was lower (P < 0.05) in SP (-6.5% points) than UT but not ET and ST. Heart rate reserve was higher (P < 0.05) in SP (104 ± 16 bpm) than UT (+21 bpm) and ST (+24 bpm), but similar to ET (+2 bpm), whereas VO2max was not significantly different in SP (30.2 ± 4.9 ml O2 · min(-1) · kg(-1)) compared to UT (+14%) and ST (+9%), but lower (P < 0.05) than ET (-22%). The number of capillaries per fibre was higher (P < 0.05) in SP than UT (53%) and ST (42%) but similar to ET. SP had less type IIx fibres than UT (-12% points). In conclusion, the exercise performance and cardiovascular health profile are markedly better for lifelong trained SP than for age-matched UT controls. Incremental exercise capacity and muscle aerobic capacity of SP are also superior to lifelong ST athletes and comparable to endurance athletes.

  15. 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

  16. 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

  17. Increased cardio-respiratory coupling evoked by slow deep breathing can persist in normal humans.

    PubMed

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

    2014-12-01

    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.

  18. Coconut fragrance and cardiovascular response to laboratory stress: results of pilot testing.

    PubMed

    Mezzacappa, Elizabeth Sibolboro; Arumugam, Uma; Chen, Sylvia Yue; Stein, Traci R; Oz, Mehmet; Buckle, Jane

    2010-01-01

    There is preliminary evidence that pleasant fragrances may alter response to stressors in different settings. This pilot study examined the effect of coconut fragrance on cardiovascular response to standard laboratory stressors. While inhaling coconut fragrance (n = 17) or air (n = 15), subjects performed a Stroop color-word task and a mental arithmetic task. Heart rate (HR), heart period variability (HPV) and blood pressure were measured during the 5-minute baseline, the task, and the recovery periods. The results indicated that subjects breathing coconut fragrance had higher HR and lower HPV than those who performed tasks while breathing air. HR response to mental arithmetic seemed to be blunted in the subjects breathing coconut; however, the lack of a difference in HPV seems to indicate that the blunting may be due to decreased sympathetic response, not decreased parasympathetic withdrawal under stress. Blood pressure recovery was slightly enhanced in subjects under coconut fragrance. Thus, the results of this pilot test suggest that coconut fragrance may alter cardiovascular activity both at rest and in response to stressors. Future experimentation should attempt to replicate and extend these findings in larger samples in clinical settings.

  19. 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.

  20. 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

  1. Clinical variability in cardiovascular disease risk factor screening and management in adolescent and young adult women with polycystic ovary syndrome

    PubMed Central

    Baer, Tamara E.; Milliren, Carly E.; Walls, Courtney; DiVasta, Amy D.

    2014-01-01

    Study Objectives To review the clinical presentation, evaluation and management of normal-weight, overweight and obese adolescent and young adult women with PCOS over 2-year follow-up. Design Retrospective chart review Participants 173 adolescent and young adult women, aged 12–22 years, diagnosed with PCOS Interventions Demographic, health data, and laboratory measures were abstracted from 3 clinic visits: baseline and 1- and 2- year follow-up. Subjects were classified as normal-weight (NW), overweight (OW) or obese (OB). Longitudinal data were analyzed using repeated measures ANOVA. Main Outcome Measures BMI, self-reported concerns, lifestyle changes. Results Most patients (73%) were OW or OB. Family history of type II diabetes was greater in OW (38%) and OB (53%) as compared to NW (22%) patients (p=0.002). Acanthosis nigricans was identified in OW (62%) and OB (21%) patients, but not NW patients (0%; p <0.001). OW and OB patients had higher fasting insulin (p<0.001) and lower HDL cholesterol (p=0.005) than NW patients, although screening rates were low. BMI Z-scores decreased in both OW and OB patients over time (0.07 units/year; p<0.001). Conclusions Most patients with PCOS were OW/OB. Substantial clinical variability existed in CVD screening; among those screened, OW and OB patients had greater CVD risk factors. Despite self-reported concerns about weight and diabetes risk among OW/OB patients, no clinically significant change in BMI percentile occurred. Evidence-based interventions and recommendations for screening tests are needed to address CVD risk in adolescents and young adults with PCOS. PMID:26081478

  2. 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.

  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. [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.

  5. 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.

  6. 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...

  7. 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.

  8. Low latency breathing frequency detection and monitoring on a personal computer.

    PubMed

    Leskovsek, Matevz; Ahlin, Dragomira; Cancer, Rok; Hosta, Milan; Enova, Dusan; Pusenjak, Nika; Bunc, Matjaz

    2011-01-01

    We demonstrate a low latency respiratory/breathing frequency detection system that is fast (<5 ms), easy to operate, requires no batteries or external power supply and operates fully via computer-standard USB connection. Exercises in controlling ones breathing frequency, usually referred to as paced-breathing exercises, have shown positive effects in treating pulmonary diseases, cardiovascular diseases and stress/anxiety-related disorders. We developed a breathing frequency detection system which uses two pairs of microphones to detect exhalation activity, eliminate noise from the environment and stream the recording data via USB connection to a personal computer. It showed 97.1% reliability (10 subjects) when monitoring breathing activity in non-guided free breathing and 100% reliability (10 subjects) when monitoring breathing activity during interactive paced-breathing exercises. We also evaluated the breathing frequency detection systems noise elimination functionality which showed a reduction of 84.2 dB for stationary (white noise) and a reduction of 79.3 dB for non-stationary (hands clapping) noise.

  9. Long-term blood pressure variability in patients with rheumatoid arthritis (RA) and its impact on cardiovascular events and all-cause mortality in RA: a population-based comparative cohort study

    PubMed Central

    Myasoedova, Elena; Crowson, Cynthia S.; Green, Abigail B.; Matteson, Eric L.; Gabriel, Sherine E.

    2014-01-01

    Objectives To examine long-term visit-to-visit blood pressure (BP) variability in rheumatoid arthritis (RA) vs non-RA subjects and to assess its impact on cardiovascular events and mortality in RA. Methods Clinic BP measures were collected in a population-based incident cohort of RA patients (1987 ACR criteria met between 1/1/1995 and 1/1/2008) and non-RA subjects. BP variability was defined as within-subject standard deviation (SD) in systolic and diastolic BP. Results Study included 442 RA patients (mean age 55.5 years, 70% females) and 424 non-RA subjects (mean age 55.7 years, 69% females). RA patients had higher visit-to-visit variability in systolic BP (13.8±4.7 mm Hg), than non-RA subjects (13.0±5.2 mm Hg, p=0.004). Systolic BP variability declined after the index date in RA (p<0.001), but not in the non-RA cohort (p=0.73), adjusting for age, sex and calendar year of RA. During the mean follow-up of 7.1 years, 33 cardiovascular events and 57 deaths occurred in RA cohort. Visit-to-visit systolic BP variability was associated with increased risk of cardiovascular events (hazard ratio [HR] per 1 mm Hg increase in BP variability 1.12, 95% confidence interval [CI] 1.01-1.25); diastolic BP variability was associated with all-cause mortality in RA (HR 1.14, 95%CI 1.03-1.27), adjusting for systolic and diastolic BP, body mass index, smoking, diabetes, dyslipidemia, use of antihypertensives. Conclusion Patients with RA had higher visit-to-visit systolic BP variability vs non-RA subjects. There was a significant decline in systolic BP variability after RA incidence. Higher visit-to-visit BP variability was associated with adverse cardiovascular outcomes and all-cause mortality in RA. PMID:24986852

  10. Efficient storage system for breath hydrogen.

    PubMed

    Murray, R D; Kerzner, B; MacLean, W C; McClung, H J; Gilbert, M

    1985-10-01

    Recommended materials for breath hydrogen collection (plastic syringes with twist lock closure) are only adequate for relatively brief periods because of gradual hydrogen loss and considerable variability between duplicate samples. To document the most favorable storage conditions for breath hydrogen, we compared hydrogen retention in plastic syringes using a conventional twist-in-lock closure versus a simple, inexpensive syringe closure, a Critocap. Hydrogen retention was studied at 25, 5, and -20 degrees C in two different syringe brands over 72 h of storage. An analysis of variance confirms the superiority of Critocaps over twist-in-lock closures (p less than 0.001). Reliability was maximal when samples were placed in environments less than 5 degrees C. When storage time was extended to 7 days, mean hydrogen retention was 86 +/- 6% (means +/- SD).

  11. The US Navy/Canadian DCIEM research initiative on pressure breathing physiology

    NASA Technical Reports Server (NTRS)

    Whitley, Phillip E.

    1994-01-01

    Development of improved positive pressure breathing garments for altitude and acceleration protection has occurred without collection of sufficient physiological data to understand the mechanisms of the improvement. Furthermore, modeling of the predicted response of future enhanced garments is greatly hampered by this lack of information. A joint, international effort is under way between Canada's Defense and Civil Institute for Environmental Medicine (DCIEM) and the US Navy's Naval Air Warfare Center Aircraft Division, Warminster (NAWCACDIVWAR). Using a Canadian subject pool, experiments at both the DCIEM altitude facility and the NAWCADIVWAR Dynamic Flight Simulator have been conducted to determine the cardiovascular and respiratory consequences of high levels of positive pressure breathing for altitude and positive pressure breathing for acceleration protection. Various improved pressure breathing garments were used to collect comparative physiological and performance data. New pressure breathing level and durahon capabilities have been encountered. Further studies will address further improvements in pressure suit design and correlation of altitude and acceleration data.

  12. Significance of Cardiac Rehabilitation on Visit-to-Visit Variability of Blood Pressure in Patients With Cardiovascular Disease in a 12-Month Follow-Up

    PubMed Central

    Ishida, Toshihisa; Miura, Shin-ichiro; Fujimi, Kanta; Futami, Makito; Ueda, Yoko; Ueda, Takashi; Arimura, Tadaaki; Koyoshi, Rie; Shiga, Yuhei; Kitajima, Ken; Saku, Keijiro

    2017-01-01

    Background Visit-to-visit variability (VVV) in blood pressure (BP) has been shown to be a strong predictor of cardiovascular disease (CVD). However, the long-term effect of comprehensive cardiac rehabilitation (CR) with exercise training on VVV in BP has not yet been established. Therefore, we evaluated the long-term effects of CR on VVV in BP in patients with CVD. Methods Twenty-two CVD patients in a 12-month CR program who had at least six clinic visits per month to measure BP were enrolled. We determined VVV in BP expressed as the standard deviation of average BP every month for 12 months. Results The mean age was 70 ± 8 years and the body mass index was 24.4 ± 4.9 kg/m2. In addition, the percentage (%) of males, % heart failure and % ischemic heart disease were 77%, 55% and 27%, respectively. Patients who had uncontrolled BP at baseline showed a significant reduction of both systolic BP (SBP) and diastolic BP (DBP). VVV in SBP in the first month was significantly less than that in the last month, although there was no difference in VVV in DBP. Patients were divided into larger (L-) and smaller (S-) VVV in SBP groups according to the average value of VVV in SBP as a cut-off. The L-VVV in SBP group, but not the S-VVV in SBP group, showed a significant reduction of VVV in SBP. Conclusion Comprehensive CR may improve VVV in SBP in CVD patients who have larger VVV in SBP. PMID:28270895

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 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 breathing gas and liquefied breathing gas containers; minimum requirements. (a) Compressed breathing gas...

  14. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 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 breathing gas and liquefied breathing gas containers; minimum requirements. (a) Compressed breathing gas...

  15. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 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 breathing gas and liquefied breathing gas containers; minimum requirements. (a) Compressed breathing gas...

  16. Sleep-Disordered Breathing

    PubMed Central

    Markov, Dimitri; Doghramji, Karl

    2006-01-01

    Sleep disorders are becoming more prevalent. There is an overlap of symptoms related to obstructive sleep apnea syndrome (OSAS) and many psychiatric conditions. Complaints of excessive sleepiness, insomnia, cognitive dysfunction, and depressive symptoms can be related to both disease states. Obstructive sleep apnea syndrome is characterized by repetitive disruption of sleep by cessation of breathing and was first described in the 19th century by bedside observation during sleep. Physicians observed this cessation of breathing while the patient slept and postulated that these episodes were responsible for subsequent complaints of sleepiness. OSAS can coexist with major depressive disorder, exacerbate depressive symptoms, or be responsible for a large part of the symptom complex of depression. Additionally, in schizophrenia, sleep apnea may develop as a result of chronic neuroleptic treatment and its effect on gains in body weight, a major risk factor for the development of OSAS. It is important to recognize the signs and symptoms of sleep apnea, namely excessive daytime sleepiness, snoring, and witnessed apneas. Recognition of the existence of sleep apnea, prompt referral to a sleep specialist, and ultimately treatment of an underlying sleep disorder, such as OSAS, can ameliorate symptoms of psychiatric disease. PMID:20975818

  17. Impact of Real-Time Continuous Glucose Monitoring Use on Glucose Variability and Endothelial Function in Adolescents with Type 1 Diabetes: New Technology—New Possibility to Decrease Cardiovascular Risk?

    PubMed Central

    Jamiołkowska, Milena; Jamiołkowska, Izabela; Łuczyński, Włodzimierz; Tołwińska, Joanna; Bossowski, Artur; Głowińska Olszewska, Barbara

    2016-01-01

    Children with type 1 diabetes (T1DM) are the high-risk group of accelerated atherosclerosis. Real-time continuous glucose monitoring (RT-CGM) provides possibilities for the detection of glycaemic variability, newly recognized cardiovascular risk factor. The aim of the study was to assess the usefulness of RT-CGM as an educational tool to find and reduce glycaemic variability in order to improve endothelial function in T1DM adolescents. Forty patients aged 14.6 years were recruited. The study was based on one-month CGM sensors use. Parameters of glycaemic variability were analyzed during first and last sensor use, together with brachial artery flow-mediated dilatation (FMD) to assess endothelial function. In the whole group, FMD improvement was found (10.9% to 16.6%, p < 0.005), together with decrease in all studied glycaemic variability parameters. In patients with HbA1c improvement compared to the group without HbA1c improvement, we found greater increase of FMD (12% to 19%, p < 0.005 versus 8.2% to 11.3%, p = 0.080) and greater improvement of glucose variability. RT-CGM can be considered as an additional tool that offers T1DM adolescents the quick reaction to decrease glycaemic variability in short time observation. Whether such approach might influence improvement in endothelial function and reduction of the risk of future cardiovascular disease remains to be elucidated. PMID:26649320

  18. A Pilot Study on the Effects of Slow Paced Breathing on Current Food Craving.

    PubMed

    Meule, Adrian; Kübler, Andrea

    2017-03-01

    Heart rate variability biofeedback (HRV-BF) involves slow paced breathing (approximately six breaths per minute), thereby maximizing low-frequent heart rate oscillations and baroreflex gain. Mounting evidence suggests that HRV-BF promotes symptom reductions in a variety of physical and mental disorders. It may also positively affect eating behavior by reducing food cravings. The aim of the current study was to investigate if slow paced breathing can be useful for attenuating momentary food craving. Female students performed paced breathing either at six breaths per minute (n = 32) or at nine breaths per minute (n = 33) while watching their favorite food on the computer screen. Current food craving decreased during a first resting period, increased during paced breathing, and decreased during a second resting period in both conditions. Although current hunger increased in both conditions during paced breathing as well, it remained elevated after the second resting period in the nine breaths condition only. Thus, breathing rate did not influence specific food craving, but slow paced breathing appeared to have a delayed influence on state hunger. Future avenues are suggested for the study of HRV-BF in the context of eating behavior.

  19. Hydrogen breath test in schoolchildren.

    PubMed

    Douwes, A C; Schaap, C; van der Klei-van Moorsel, J M

    1985-04-01

    The frequency of negative hydrogen breath tests due to colonic bacterial flora which are unable to produce hydrogen was determined after oral lactulose challenge in 98 healthy Dutch schoolchildren. There was a negative result in 9.2%. The probability of a false normal lactose breath test (1:77) was calculated from these results together with those from a separate group of children with lactose malabsorption (also determined by hydrogen breath test). A study of siblings and mothers of subjects with a negative breath test did not show familial clustering of this condition. Faecal incubation tests with various sugars showed an increase in breath hydrogen greater than 100 parts per million in those with a positive breath test while subjects with a negative breath test also had a negative faecal incubation test. The frequency of a false negative hydrogen breath test was higher than previously reported, but this does not affect the superiority of this method of testing over the conventional blood glucose determination.

  20. 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…

  1. Breath in the technoscientific imaginary.

    PubMed

    Rose, Arthur

    2016-12-01

    Breath has a realist function in most artistic media. It serves to remind the reader, the viewer or the spectator of the exigencies of the body. In science fiction (SF) literature and films, breath is often a plot device for human encounters with otherness, either with alien peoples, who may not breathe oxygen, or environments, where there may not be oxygen to breathe. But while there is a technoscientific quality to breath in SF, especially in its attention to physiological systems, concentrating on the technoscientific threatens to occlude other, more affective aspects raised by the literature. In order to supplement the tendency to read SF as a succession of technoscientific accounts of bodily experience, this paper recalls how SF texts draw attention to the affective, non-scientific qualities of breath, both as a metonym for life and as a metaphor for anticipation. Through an engagement with diverse examples from SF literature and films, this article considers the tension between technoscientific and affective responses to breath in order to demonstrate breath's co-determinacy in SF's blending of scientific and artistic discourses.

  2. What Happens When You Breathe?

    MedlinePlus

    ... Explore How the Lungs Work What Are... The Respiratory System What Happens When You Breathe What Controls Your Breathing Lung Diseases & Conditions Clinical Trials Links Related Topics Asthma Bronchitis COPD How the Heart Works Respiratory Failure Send a link to NHLBI to someone ...

  3. Breath in the technoscientific imaginary

    PubMed Central

    Rose, Arthur

    2016-01-01

    Breath has a realist function in most artistic media. It serves to remind the reader, the viewer or the spectator of the exigencies of the body. In science fiction (SF) literature and films, breath is often a plot device for human encounters with otherness, either with alien peoples, who may not breathe oxygen, or environments, where there may not be oxygen to breathe. But while there is a technoscientific quality to breath in SF, especially in its attention to physiological systems, concentrating on the technoscientific threatens to occlude other, more affective aspects raised by the literature. In order to supplement the tendency to read SF as a succession of technoscientific accounts of bodily experience, this paper recalls how SF texts draw attention to the affective, non-scientific qualities of breath, both as a metonym for life and as a metaphor for anticipation. Through an engagement with diverse examples from SF literature and films, this article considers the tension between technoscientific and affective responses to breath in order to demonstrate breath's co-determinacy in SF's blending of scientific and artistic discourses. PMID:27542677

  4. Clinical applications of breath testing

    PubMed Central

    Paschke, Kelly M; Mashir, Alquam

    2010-01-01

    Breath testing has the potential to benefit the medical field as a cost-effective, non-invasive diagnostic tool for diseases of the lung and beyond. With growing evidence of clinical worth, standardization of methods, and new sensor and detection technologies the stage is set for breath testing to gain considerable attention and wider application in upcoming years. PMID:21173863

  5. 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.

  6. 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.

  7. Blood pressure regulation, autonomic control and sleep disordered breathing in children.

    PubMed

    Nisbet, Lauren C; Yiallourou, Stephanie R; Walter, Lisa M; Horne, Rosemary S C

    2014-04-01

    Sleep disordered breathing (SDB) ranges in severity from primary snoring (PS) to obstructive sleep apnoea (OSA). In adults, SDB is associated with adverse cardiovascular consequences which are mediated, in part, by autonomic dysfunction. Although SDB is common in children, fewer paediatric studies have investigated these cardiovascular effects. Initial research focused on those with OSA, indeed children with PS were occasionally utilised as the comparison control group. However, it is essential to understand the ramifications of this disorder in all its severities, as currently the milder forms of SDB are often untreated. Methodologies used to assess autonomic function in children with SDB include blood pressure (BP), BP variability, baroreflex sensitivity, heart rate variability, peripheral arterial tonometry and catecholamine assays. The aim of this review was to summarise the findings of paediatric studies to date and explore the relationship between autonomic dysfunction and SDB in children, paying particular attention to the roles of disease severity and/or age. This review found evidence of autonomic dysfunction in children with SDB during both wakefulness and sleep. BP dysregulation, elevated generalised sympathetic activity and impairment of autonomic reflexes occur in school-aged children and adolescents with SDB. The adverse effects of SDB seem somewhat less in young children, although more studies are needed. There is mounting evidence that the cardiovascular and autonomic consequences of SDB are not limited to those with OSA, but are also evident in children with PS. The severity of disease and age of onset of autonomic consequences may be important guides for the treatment of SDB.

  8. 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.

  9. Breathing zone air sampler

    SciTech Connect

    Tobin, J.

    1989-08-22

    A sampling apparatus is presented 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. Plasma coenzyme Q10 concentration, antioxidant status, and serum N-terminal pro-brain natriuretic peptide concentration in dogs with various cardiovascular diseases and the effect of cardiac treatment on measured variables.

    PubMed

    Svete, Alenka Nemec; Verk, Barbara; Seliškar, Alenka; Tomsič, Katerina; Križman, Petra Jazbec; Petrič, Aleksandra Domanjko

    2017-04-01

    OBJECTIVE To determine the plasma total antioxidant capacity, erythrocyte superoxide dismutase activity, whole blood glutathione peroxidase activity, and plasma coenzyme Q10 (CoQ10) concentration in dogs with various stages of cardiovascular diseases and in healthy dogs; assess the influence of cardiac treatment on the levels of antioxidant variables, plasma CoQ10 concentration, and serum N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration, and determine any correlation between the disease severity (NT-proBNP concentration) and antioxidant variables or CoQ10 concentration. ANIMALS 43 dogs with various types and stages of cardiovascular diseases (congenital and acquired) and 29 healthy dogs. PROCEDURES Blood samples were collected from all dogs for spectrophotometric assessment of antioxidant variables. Plasma CoQ10 concentration was determined with a high-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry method. Serum NT-proBNP concentration was measured with an ELISA. RESULTS Values for antioxidant variables did not differ among groups of dogs with cardiovascular diseases, regardless of disease stage or treatment. Plasma CoQ10 concentration was significantly increased in treated dogs with congestive heart failure (CHF), compared with untreated patients. However, plasma CoQ10 concentration did not differ among heart failure classes. A significant, negative correlation between serum NT-proBNP and plasma CoQ10 concentrations was identified in treated CHF-affected dogs, suggesting that low plasma CoQ10 concentration may be associated with increased severity of CHF. CONCLUSIONS AND CLINICAL RELEVANCE The antioxidant variables evaluated were not altered in dogs with CHF, regardless of cardiac disease stage or treatment. Further investigation into the possible effects of CoQ10 supplementation in dogs with advanced stages of CHF is warranted.

  11. 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

  12. Detection of cancer through exhaled breath: a systematic review

    PubMed Central

    Krilaviciute, Agne; Heiss, Jonathan Alexander; Leja, Marcis; Kupcinskas, Juozas; Haick, Hossam; Brenner, Hermann

    2015-01-01

    Background Timely diagnosis of cancer represents a challenging task; in particular, there is a need for reliable non-invasive screening tools that could achieve high levels of adherence at virtually no risk in population-based screening. In this review, we summarize the current evidence of exhaled breath analysis for cancer detection using standard analysis techniques and electronic nose. Methods Relevant studies were identified searching Pubmed and Web of Science databases until April 30, 2015. Information on breath test performance, such as sensitivity and specificity, was extracted together with volatile compounds that were used to discriminate cancer patients from controls. Performance of different breath analysis techniques is provided for various cancers together with information on methodological issues, such as breath sampling protocol and validation of the results. Results Overall, 73 studies were included, where two-thirds of the studies were conducted on lung cancer. Good discrimination usually required a combination of multiple biomarkers, and area under the receiver operating characteristic curve or accuracy reached levels of 0.9 or higher in multiple studies. In 25% of the reported studies, classification models were built and validated on the same datasets. Huge variability was seen in different aspects among the studies. Conclusions Analyses of exhaled breath yielded promising results, although standardization of breath collection, sample storage and data handling remain critical issues. In order to foster breath analysis implementation into practice, larger studies should be implemented in true screening settings, paying particular attention to standardization in breath collection, consideration of covariates, and validation in independent population samples. PMID:26440312

  13. Measurement of breath acetone concentrations by selected ion flow tube mass spectrometry in type 2 diabetes.

    PubMed

    Storer, Malina; Dummer, Jack; Lunt, Helen; Scotter, Jenny; McCartin, Fiona; Cook, Julie; Swanney, Maureen; Kendall, Deborah; Logan, Florence; Epton, Michael

    2011-12-01

    Selected ion flow tube-mass spectrometry (SIFT-MS) can measure volatile compounds in breath on-line in real time and has the potential to provide accurate breath tests for a number of inflammatory, infectious and metabolic diseases, including diabetes. Breath concentrations of acetone in type 2 diabetic subjects undertaking a long-term dietary modification programme were studied. Acetone concentrations in the breath of 38 subjects with type 2 diabetes were determined by SIFT-MS. Anthropomorphic measurements, dietary intake and medication use were recorded. Blood was analysed for beta hydroxybutyrate (a ketone body), HbA1c (glycated haemoglobin) and glucose using point-of-care capillary (fingerprick) testing. All subjects were able to undertake breath manoeuvres suitable for analysis. Breath acetone varied between 160 and 862 ppb (median 337 ppb) and was significantly higher in men (median 480 ppb versus 296 ppb, p = 0.01). In this cross-sectional study, no association was observed between breath acetone and either dietary macronutrients or point-of-care capillary blood tests. Breath analysis by SIFT-MS offers a rapid, reproducible and easily performed measurement of acetone concentration in ambulatory patients with type 2 diabetes. The high inter-individual variability in breath acetone concentration may limit its usefulness in cross-sectional studies. Breath acetone may nevertheless be useful for monitoring metabolic changes in longitudinal metabolic studies, in a variety of clinical and research settings.

  14. C-130J Breathing Resistance Study

    DTIC Science & Technology

    2016-05-01

    the long breathing hose configurations did not provide acceptable breathing resistance in a significant majority of test conditions. 15...requirements in the Air Standard. In general, breathing resistance of the system with the long breathing hoses did not meet the Air Standard

  15. Visualizing Breath using Digital Holography

    NASA Astrophysics Data System (ADS)

    Hobson, P. R.; Reid, I. D.; Wilton, J. B.

    2013-02-01

    Artist Jayne Wilton and physicists Peter Hobson and Ivan Reid of Brunel University are collaborating at Brunel University on a project which aims to use a range of techniques to make visible the normally invisible dynamics of the breath and the verbal and non-verbal communication it facilitates. The breath is a source of a wide range of chemical, auditory and physical exchanges with the direct environment. Digital Holography is being investigated to enable a visually stimulating articulation of the physical trajectory of the breath as it leaves the mouth. Initial findings of this research are presented. Real time digital hologram replay allows the audience to move through holographs of breath-born particles.

  16. Liquid-Air Breathing Apparatus

    NASA Technical Reports Server (NTRS)

    Mills, Robert D.

    1990-01-01

    Compact unit supplies air longer than compressed-air unit. Emergency breathing apparatus stores air as cryogenic liquid instead of usual compressed gas. Intended for firefighting or rescue operations becoming necessary during planned potentially hazardous procedures.

  17. Shortness of Breath and Eating

    MedlinePlus

    ... 877-CALL NJH (877.225.5654) Submit About Us Careers Patient Portal Login Patients & ... of breath can make eating hard work. If you use all your energy preparing a healthy meal, you may find yourself ...

  18. Baroreceptor output during normal and obstructed breathing and Mueller maneuvers.

    PubMed

    Fitzgerald, R S; Robotham, J L; Anand, A

    1981-05-01

    Cardiovascular control during asthma and other forms of obstructed breathing has not been extensively investigated. Previous studies in dogs have shown that obstructed breathing or an inspiratory effort against a blocked airway (Mueller maneuver) provoke large oscillations in blood pressure. During the inspiratory phase transmural systolic pressure relative to atmosphere drops initially, but transmural systolic pressure relative to intrathoracic pressure can remain unchanged or even increase. Because the carotid baroreceptors are located in the extrathoracic circulation, whereas the aortic baroreceptors are located in the intrathoracic circulation, and each responds to local transmural arterial pressure, simultaneous baroreceptor output from these two areas was measured in the anesthetized cat during normal and obstructed breathing and during Mueller maneuvers. Both whole-nerve and single-fiber preparations showed a significantly decreased output from the carotid baroreceptors during obstructed inspiratory efforts, whereas aortic baroreceptor output decreased significantly less or not at all. Transmural systolic pressure decreased significantly less in the aorta than in the carotid regions. Further, the aortic baroreceptors were more sensitive to changes in pulse pressure than were the carotid baroreceptors. These results suggest a mechanism for stabilizing the cardiac responses to precipitous falls in blood pressure that occur in obstructed breathing.

  19. Arterial hypertension in migraine: Role of familial history and cardiovascular phenotype.

    PubMed

    Babayan, Laura; Mamontov, Oleg V; Amelin, Alexander V; Bogachev, Mikhail; Kamshilin, Alexei A

    2017-03-01

    Recent studies indicate that migraine is associated with increased risk of cardiovascular diseases. However, links between autonomic cardiovascular regulation, arterial hypertension (AH) and migraine are still little explored. In this study, we evaluated autonomic regulation in migraine patients with and without hypertension. We studied 104 patients with migraine, aged 34±10 y, including 28 with and 76 without hypertension (M+AH and M-AH groups, respectively). The control group consisted of 88 healthy volunteers matched by age and sex. The autonomic regulation of circulation was examined with the tilt-table test, deep-breathing and Valsalva Maneuver, handgrip test, cold-stress induced vasoconstriction, arterial baroreflex, and blood pressure variability measurements. We found that migraine patients with concomitant hypertension demonstrated reduced arterial baroreflex, whereas other parameters of cardiac autonomic regulation were unchanged. In contrast, most indicators of vasomotor reactivity (blood pressure response to the hand-grip, Valsalva maneuver and cold vasoconstriction) were enhanced in migraine patients with no significant differences between migraine patients with and without hypertension. Patients from both M+AH and M-AH groups more commonly had a family history of cardiovascular disorders. Our data revealed increased vasomotor reactivity in migraine patients, with or without concomitant hypertension. This was associated with the family history of cardiovascular diseases.

  20. 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

  1. Optimization of Air-Breathing Engine Concept

    NASA Technical Reports Server (NTRS)

    Patnaik, Surya N.; Lavelle, Thomas M.; Hopkins, Dale A.

    1996-01-01

    The design optimization of air-breathing propulsion engine concepts has been accomplished by soft-coupling the NASA Engine Performance Program (NEPP) analyzer with the NASA Lewis multidisciplinary optimization tool COMETBOARDS. Engine problems, with their associated design variables and constraints, were cast as nonlinear optimization problems with thrust as the merit function. Because of the large number of mission points in the flight envelope, the diversity of constraint types, and the overall distortion of the design space; the most reliable optimization algorithm available in COMETBOARDS, when used by itself, could not produce satisfactory, feasible, optimum solutions. However, COMETBOARDS' unique features-which include a cascade strategy, variable and constraint formulations, and scaling devised especially for difficult multidisciplinary applications-successfully optimized the performance of subsonic and supersonic engine concepts. Even when started from different design points, the combined COMETBOARDS and NEPP results converged to the same global optimum solution. This reliable and robust design tool eliminates manual intervention in the design of air-breathing propulsion engines and eases the cycle analysis procedures. It is also much easier to use than other codes, which is an added benefit. This paper describes COMETBOARDS and its cascade strategy and illustrates the capabilities of the combined design tool through the optimization of a high-bypass- turbofan wave-rotor-topped subsonic engine and a mixed-flow-turbofan supersonic engine.

  2. 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...

  3. Cardiovascular Pharmacology of Cannabinoids

    PubMed Central

    Pacher, P.; Bátkai, S.; Kunos, G.

    2008-01-01

    Cannabinoids and their synthetic and endogenous analogs affect a broad range of physiological functions, including cardiovascular variables, the most important component of their effect being profound hypotension. The mechanisms of the cardiovascular effects of cannabinoids in vivo are complex and may involve modulation of autonomic outflow in both the central and peripheral nervous systems as well as direct effects on the myocardium and vasculature. Although several lines of evidence indicate that the cardiovascular depressive effects of cannabinoids are mediated by peripherally localized CB1 receptors, recent studies provide strong support for the existence of as-yet-undefined endothelial and cardiac receptor(s) that mediate certain endocannabinoid-induced cardiovascular effects. The endogenous cannabinoid system has been recently implicated in the mechanism of hypotension associated with hemorrhagic, endotoxic, and cardiogenic shock, and advanced liver cirrhosis. Furthermore, cannabinoids have been considered as novel antihypertensive agents. A protective role of endocannabinoids in myocardial ischemia has also been documented. In this chapter, we summarize current information on the cardiovascular effects of cannabinoids and highlight the importance of these effects in a variety of pathophysiological conditions. PMID:16596789

  4. 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.

  5. Autonomic nervous system abnormalities in spinocerebellar ataxia type 2: a cardiovascular neurophysiologic study.

    PubMed

    De Joanna, G; De Rosa, A; Salvatore, E; Castaldo, I; De Luca, N; Izzo, R; Manzo, V; Filla, A; De Michele, G

    2008-12-15

    Autonomic nervous system dysfunction is part of the spinocerebellar ataxia (SCA) clinical picture, but few data are available on this topic. The present study is aimed to report a detailed investigation of autonomic nervous system in patients with molecular diagnosis of SCA type 2, one of the most frequent forms and the commonest in Italy. Nine patients with a mild to moderate form of SCA2 underwent a questionnaire about dysautonomic symptoms and a complete cardiovascular neurophysiologic evaluation of both sympathetic and parasympathetic system, comprising head-up tilt, standing, isometric hand grip, cold pressure, mental arithmetic, Valsalva manoeuvre, deep breathing, and hyperventilation tests. An echocardiographic study and Holter-ECG recording were also performed. All patients complained dysautonomic problems regarding urinary tract, cardiovascular system, or gastrointestinal dysfunction. The neurophysiologic study showed both sympathetic and parasympathetic involvement, with highly variable degree and pattern of dysautonomia. The present study results show that the autonomic dysfunction is common in SCA2 representing a significant component of the complex picture of the disease. We found a wide spectrum of cardiovascular autonomic abnormalities, without a typical pattern of dysfunction and without correlation with clinical variables.

  6. The physiology and pathophysiology of human breath-hold diving.

    PubMed

    Lindholm, Peter; Lundgren, Claes E G

    2009-01-01

    This is a brief overview of physiological reactions, limitations, and pathophysiological mechanisms associated with human breath-hold diving. Breath-hold duration and ability to withstand compression at depth are the two main challenges that have been overcome to an amazing degree as evidenced by the current world records in breath-hold duration at 10:12 min and depth of 214 m. The quest for even further performance enhancements continues among competitive breath-hold divers, even if absolute physiological limits are being approached as indicated by findings of pulmonary edema and alveolar hemorrhage postdive. However, a remarkable, and so far poorly understood, variation in individual disposition for such problems exists. Mortality connected with breath-hold diving is primarily concentrated to less well-trained recreational divers and competitive spearfishermen who fall victim to hypoxia. Particularly vulnerable are probably also individuals with preexisting cardiac problems and possibly, essentially healthy divers who may have suffered severe alternobaric vertigo as a complication to inadequate pressure equilibration of the middle ears. The specific topics discussed include the diving response and its expression by the cardiovascular system, which exhibits hypertension, bradycardia, oxygen conservation, arrhythmias, and contraction of the spleen. The respiratory system is challenged by compression of the lungs with barotrauma of descent, intrapulmonary hemorrhage, edema, and the effects of glossopharyngeal insufflation and exsufflation. Various mechanisms associated with hypoxia and loss of consciousness are discussed, including hyperventilation, ascent blackout, fasting, and excessive postexercise O(2) consumption. The potential for high nitrogen pressure in the lungs to cause decompression sickness and N(2) narcosis is also illuminated.

  7. 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

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

    PubMed

    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

  9. 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

  10. Cardiovascular risk

    PubMed Central

    Payne, Rupert A

    2012-01-01

    Cardiovascular disease is a major, growing, worldwide problem. It is important that individuals at risk of developing cardiovascular disease can be effectively identified and appropriately stratified according to risk. This review examines what we understand by the term risk, traditional and novel risk factors, clinical scoring systems, and the use of risk for informing prescribing decisions. Many different cardiovascular risk factors have been identified. Established, traditional factors such as ageing are powerful predictors of adverse outcome, and in the case of hypertension and dyslipidaemia are the major targets for therapeutic intervention. Numerous novel biomarkers have also been described, such as inflammatory and genetic markers. These have yet to be shown to be of value in improving risk prediction, but may represent potential therapeutic targets and facilitate more targeted use of existing therapies. Risk factors have been incorporated into several cardiovascular disease prediction algorithms, such as the Framingham equation, SCORE and QRISK. These have relatively poor predictive power, and uncertainties remain with regards to aspects such as choice of equation, different risk thresholds and the roles of relative risk, lifetime risk and reversible factors in identifying and treating at-risk individuals. Nonetheless, such scores provide objective and transparent means of quantifying risk and their integration into therapeutic guidelines enables equitable and cost-effective distribution of health service resources and improves the consistency and quality of clinical decision making. PMID:22348281

  11. Cardiovascular Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cardiovascular disease (CVD), particularly CHD (coronary heart disease) and stroke, remain the leading causes of death of women in America and most developed countries. In recent years the rate of CVD has declined in men but not in women. This is contributed to by an under-recognition of women’s C...

  12. Can Breath Test Detect Stomach Cancers Earlier?

    MedlinePlus

    ... news/fullstory_163342.html Can Breath Test Detect Stomach Cancers Earlier? New technology may also spot esophageal ... 2017 (HealthDay News) -- A breath test to detect stomach and esophageal cancers shows promise, researchers say. The ...

  13. 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

  14. Breathing Problems: An Individualized Program.

    ERIC Educational Resources Information Center

    Vodola, Thomas M.

    As one of the components of the Project ACTIVE (All Children Totally Involved Exercising) Teacher Training Model Kit, the manual is designed to enable the educator to organize, conduct, and evaluate individualized-personalized physical education programs for children (prekindergarten through high school) with breathing problems. An introductory…

  15. 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...

  16. Pharmacogenetics of cardiovascular drugs.

    PubMed

    Johnson, Julie A; Humma, Larisa M

    2002-02-01

    Pharmacogenetics is a field aimed at understanding the genetic contribution to inter-patient variability in drug efficacy and toxicity. Treatment of cardiovascular disease is, in most cases, guided by evidence from well-controlled clinical trials. Given the solid scientific basis for the treatment of most cardiovascular diseases, it is common for patients with a given disease to be treated in essentially the same manner. Thus, the clinical trials have been very informative about treating large groups of patients with a given disease, but are slightly less informative about the treatment of individual patients. Pharmacogenetics and pharmacogenomics have the potential of taking the information derived from large clinical trials and further refining it to select the drugs with the greatest likelihood for benefit, and least likelihood for harm, in individual patients, based on their genetic make-up. In this paper, the current literature on cardiovascular pharmacogenetics is emphasised, and how the use of pharmacogenetic/pharmacogenomic information may be particularly useful in the future in the treatment of cardiovascular diseases is also highlighted.

  17. Functional Analysis and Intervention for Breath Holding.

    ERIC Educational Resources Information Center

    Kern, Lee; And Others

    1995-01-01

    A functional analysis of breath-holding episodes in a 7-year-old girl with severe mental retardation and Cornelia-de-Lange syndrome indicated that breath holding served an operant function, primarily to gain access to attention. Use of extinction, scheduled attention, and a picture card communication system decreased breath holding. (Author/SW)

  18. 21 CFR 868.5620 - Breathing mouthpiece.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing mouthpiece. 868.5620 Section 868.5620...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5620 Breathing mouthpiece. (a) Identification. A breathing mouthpiece is a rigid device that is inserted into a patient's mouth and...

  19. 21 CFR 868.5620 - Breathing mouthpiece.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing mouthpiece. 868.5620 Section 868.5620...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5620 Breathing mouthpiece. (a) Identification. A breathing mouthpiece is a rigid device that is inserted into a patient's mouth and...

  20. 21 CFR 868.5620 - Breathing mouthpiece.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breathing mouthpiece. 868.5620 Section 868.5620...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5620 Breathing mouthpiece. (a) Identification. A breathing mouthpiece is a rigid device that is inserted into a patient's mouth and...

  1. 21 CFR 868.5620 - Breathing mouthpiece.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing mouthpiece. 868.5620 Section 868.5620...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5620 Breathing mouthpiece. (a) Identification. A breathing mouthpiece is a rigid device that is inserted into a patient's mouth and...

  2. 21 CFR 868.5620 - Breathing mouthpiece.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breathing mouthpiece. 868.5620 Section 868.5620...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5620 Breathing mouthpiece. (a) Identification. A breathing mouthpiece is a rigid device that is inserted into a patient's mouth and...

  3. Respiratory difficulties and breathing disorders in achondroplasia.

    PubMed

    Afsharpaiman, S; Saburi, A; Waters, Karen A

    2013-12-01

    Respiratory difficulties and breathing disorders in achondroplasia are thought to underlie the increased risk for sudden infant death and neuropsychological deficits seen in this condition. This review evaluates literature regarding respiratory dysfunctions and their sequelae in patients with achondroplasia. The limited number of prospective studies of respiratory disease in achondroplasia means that observational studies and case series provide a large proportion of the data regarding the spectrum of respiratory diseases in achondroplasia and their treatments. Amongst clinical respiratory problems described, snoring is the commonest observed abnormality, but the reported incidence of obstructive sleep apnoea (OSA) shows wide variance (10% to 75%). Reported treatments of OSA include adenotonsillectomy, the use of CPAP, and surgical improvement of the airway, including mid-face advancement. Otolaryngologic manifestations are also common. Respiratory failure due to small thoracic volumes is reported, but uncommon. Mortality rate at all ages was 2.27 (CI: 1.7-3.0) with age-specific mortality increased at all ages. Sudden death was most common in infants and children. Cardiovascular events are the main cause of mortality in adults. Despite earlier recognition and treatment of respiratory complications of achondroplasia, increased mortality rates and other complications remain high. Future and ongoing evaluation of the prevalence and impact of respiratory disorders, particularly OSA, in achondroplasia is recommended.

  4. 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.

  5. 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.

  6. Envelope Analysis of the Airflow Signal To Improve Polysomnographic Assessment of Sleep Disordered Breathing

    PubMed Central

    Díaz, Javier A.; Arancibia, José M.; Bassi, Alejandro; Vivaldi, Ennio A.

    2014-01-01

    Study Objectives: Given the detailed respiratory waveform signal provided by the nasal cannula in polysomnographic (PSG) studies, to quantify sleep breathing disturbances by extracting a continuous variable based on the coefficient of variation of the envelope of that signal. Design: Application of an algorithm for envelope analysis to standard nasal cannula signal from actual polysomnographic studies. Setting: PSG recordings from a sleep disorders center were analyzed by an algorithm developed on the Igor scientific data analysis software. Patients or Participants: Recordings representative of different degrees of sleep disordered breathing (SDB) severity or illustrative of the covariation between breathing and particularly relevant factors and variables. Interventions: The method calculated the coefficient of variation of the envelope for each 30-second epoch. The normalized version of that coefficient was defined as the respiratory disturbance variable (RDV). The method outcome was the all-night set of RDV values represented as a time series. Measurements and Results: RDV quantitatively reflected departure from normal sinusoidal breathing at each epoch, providing an intensity scale for disordered breathing. RDV dynamics configured itself in recognizable patterns for the airflow limitation (e.g., in UARS) and the apnea/hypopnea regimes. RDV reliably highlighted clinically meaningful associations with staging, body position, oximetry, or CPAP titration. Conclusions: Respiratory disturbance variable can assess sleep breathing disturbances as a gradual phenomenon while providing a comprehensible and detailed representation of its dynamics. It may thus improve clinical diagnosis and provide a revealing descriptive tool for mechanistic sleep disordered breathing modeling. Respiratory disturbance variable may contribute to attaining simplified screening methodologies, novel diagnostic criteria, and insightful research tools. Citation: Díaz JA; Arancibia JM; Bassi A

  7. 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

  8. 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.

  9. Physiology of long pranayamic breathing: neural respiratory elements may provide a mechanism that explains how slow deep breathing shifts the autonomic nervous system.

    PubMed

    Jerath, Ravinder; Edry, John W; Barnes, Vernon A; Jerath, Vandna

    2006-01-01

    Pranayamic breathing, defined as a manipulation of breath movement, has been shown to contribute to a physiologic response characterized by the presence of decreased oxygen consumption, decreased heart rate, and decreased blood pressure, as well as increased theta wave amplitude in EEG recordings, increased parasympathetic activity accompanied by the experience of alertness and reinvigoration. The mechanism of how pranayamic breathing interacts with the nervous system affecting metabolism and autonomic functions remains to be clearly understood. It is our hypothesis that voluntary slow deep breathing functionally resets the autonomic nervous system through stretch-induced inhibitory signals and hyperpolarization currents propagated through both neural and non-neural tissue which synchronizes neural elements in the heart, lungs, limbic system and cortex. During inspiration, stretching of lung tissue produces inhibitory signals by action of slowly adapting stretch receptors (SARs) and hyperpolarization current by action of fibroblasts. Both inhibitory impulses and hyperpolarization current are known to synchronize neural elements leading to the modulation of the nervous system and decreased metabolic activity indicative of the parasympathetic state. In this paper we propose pranayama's physiologic mechanism through a cellular and systems level perspective, involving both neural and non-neural elements. This theoretical description describes a common physiological mechanism underlying pranayama and elucidate the role of the respiratory and cardiovascular system on modulating the autonomic nervous system. Along with facilitating the design of clinical breathing techniques for the treatment of autonomic nervous system and other disorders, this model will also validate pranayama as a topic requiring more research.

  10. Feedback linearization for control of air breathing engines

    NASA Technical Reports Server (NTRS)

    Phillips, Stephen; Mattern, Duane

    1991-01-01

    The method of feedback linearization for control of the nonlinear nozzle and compressor components of an air breathing engine is presented. This method overcomes the need for a large number of scheduling variables and operating points to accurately model highly nonlinear plants. Feedback linearization also results in linear closed loop system performance simplifying subsequent control design. Feedback linearization is used for the nonlinear partial engine model and performance is verified through simulation.

  11. Effects of diaphragm breathing exercise and feedback breathing exercise on pulmonary function in healthy adults.

    PubMed

    Yong, Min-Sik; Lee, Hae-Yong; Lee, Yun-Seob

    2017-01-01

    [Purpose] The present study investigated effects of diaphragm breathing exercise and feedback breathing exercise on respiratory function. [Subjects and Methods] Thirty-one subjects were randomly assigned to two groups; the feedback breathing exercise group and the maneuver-diaphragm exercise group. The feedback breathing exercise group was asked to breathe with feedback breathing device, and the maneuver-diaphragm exercise group was asked to perform diaphragm respiration. Respiratory function was evaluated when a subject sat on a chair comfortably. [Results] There was a significant difference in the functional vital capacity and slow vital capacity before and after all breathing exercises. There was a significant between-group difference in functional vital capacity. However, no between-group difference was found in slow vital capacity. [Conclusion] Diaphragm breathing exercise and feedback breathing exercise can affect respiratory function.

  12. Effects of diaphragm breathing exercise and feedback breathing exercise on pulmonary function in healthy adults

    PubMed Central

    Yong, Min-Sik; Lee, Hae-Yong; Lee, Yun-Seob

    2017-01-01

    [Purpose] The present study investigated effects of diaphragm breathing exercise and feedback breathing exercise on respiratory function. [Subjects and Methods] Thirty-one subjects were randomly assigned to two groups; the feedback breathing exercise group and the maneuver-diaphragm exercise group. The feedback breathing exercise group was asked to breathe with feedback breathing device, and the maneuver-diaphragm exercise group was asked to perform diaphragm respiration. Respiratory function was evaluated when a subject sat on a chair comfortably. [Results] There was a significant difference in the functional vital capacity and slow vital capacity before and after all breathing exercises. There was a significant between-group difference in functional vital capacity. However, no between-group difference was found in slow vital capacity. [Conclusion] Diaphragm breathing exercise and feedback breathing exercise can affect respiratory function. PMID:28210046

  13. Decreased Exercise Capacity and Sleep-Disordered Breathing in Patients With Hypertrophic Cardiomyopathy

    PubMed Central

    Konecny, Tomas; Geske, Jeffrey B.; Ludka, Ondrej; Orban, Marek; Brady, Peter A.; Abudiab, Muaz M.; Albuquerque, Felipe N.; Placek, Alexander; Kara, Tomas; Sahakyan, Karine R.; Gersh, Bernard J.; Tajik, A. Jamil; Allison, Thomas G.; Ommen, Steve R.

    2015-01-01

    BACKGROUND: Mechanisms of decreased exercise capacity in patients with hypertrophic cardiomyopathy (HCM) are not well understood. Sleep-disordered breathing (SDB) is a highly prevalent but treatable disorder in patients with HCM. The role of comorbid SDB in the attenuated exercise capacity in HCM has not been studied previously. METHODS: Overnight oximetry, cardiopulmonary exercise testing, and echocardiographic studies were performed in consecutive patients with HCM seen at the Mayo Clinic. SDB was considered present if the oxygen desaturation index (number of ≥ 4% desaturations/h) was ≥ 10. Peak oxygen consumption (V.o2peak) (the most reproducible and prognostic measure of cardiovascular fitness) was then correlated with the presence and severity of SDB. RESULTS: A total of 198 patients with HCM were studied (age, 53 ± 16 years; 122 men), of whom 32% met the criteria for the SDB diagnosis. Patients with SDB had decreased V.o2peak compared with those without SDB (16 mL O2/kg/min vs 21 mL O2/kg/min, P < .001). SDB remained significantly associated with V.o2peak after accounting for confounding clinical variables (P < .001) including age, sex, BMI, atrial fibrillation, and coronary artery disease. CONCLUSIONS: In patients with HCM, the presence of SDB is associated with decreased V.o2peak. SDB may represent an important and potentially modifiable contributor to impaired exercise tolerance in this unique population. PMID:25633371

  14. Air-Breathing Rocket Engines

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  15. 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.

  16. [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.

  17. Cardiovascular Cine Film Quality

    NASA Astrophysics Data System (ADS)

    Scheid, Carl C.

    1983-12-01

    The detection of a cardiovascular stenosis involves the complex interaction of technique selection, system performance and anatomy. Technique selection for instance involves choosing the correct focal spot, pulse width, KVp, and frame rate for a given patient and projection angle. In order to provide guidance in this selection process, these variables were investigated in terms of their impact on image quality. Conclusions which were confirmed clinically are summarized in terms of recommended techniques for a range of patient sizes. The confirmation includes clinical films which demonstrates the effects of parameter changes.

  18. 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

  19. Sleep disordered breathing in pregnancy

    PubMed Central

    2015-01-01

    Key points Sleep disordered breathing (SDB) is common and the severity increases as pregnancy progresses. Frequent snoring, older age and high pre-pregnancy body mass index (>25 kg⋅m−2) could be reliable indicators for SDB in early pregnancy. SDB screening tools, including questionnaires, used in the nonpregnant population have poor predictive ability in pregnancy. Accumulating evidence suggests that SDB during pregnancy may be associated with increased risk of adverse pregnancy outcomes, including gestational diabetes and pre-eclampsia. However, the results should be interpreted cautiously because several studies failed to adjust for potential maternal confounders and have other study limitations. There are no pregnancy-specific practice guidelines for SDB treatment. Many clinicians and practices follow recommendations for the treatment in the general population. Women with pre-existing SDB might need to be reassessed, particularly after the sixth month of pregnancy, because symptoms can worsen with nasal congestion and weight gain. Educational aims To highlight the prevalence and severity of sleep disordered breathing (SDB) in the pregnant population. To inform readers about risk factors for SDB in pregnancy. To explore the impact of SDB on adverse maternal and fetal outcomes, and biological pathways for associated adverse maternal and fetal outcomes. To introduce current management options for SDB in pregnancy, including medical and behavioural approaches. Sleep disordered breathing (SDB) is very common during pregnancy, and is most likely explained by hormonal, physiological and physical changes. Maternal obesity, one of the major risk factors for SDB, together with physiological changes in pregnancy may predispose women to develop SDB. SDB has been associated with poor maternal and fetal outcomes. Thus, early identification, diagnosis and treatment of SDB are important in pregnancy. This article reviews the pregnancy-related changes affecting the

  20. [Breath-analysis tests in gastroenetrological diagnosis].

    PubMed

    Caspary, W F

    1975-12-01

    The introduction of a simple method for analysis of 14CO2 in breath allowed a more widely application of breath-tests in the diagnosis of gastroenterological diseases. During a breath-test a 14C-labelled compound is administered orally and 14CO2 is subsequently measured in breath by discontinuous samplings of 14CO2 by virtue of a trapping solution (hyamine hydroxide). Most helpful tests in gastroenterology are the 14C-glycyl-cholate breath test for detecting increased deconjugation of bile acids due to small intestinal bacterial overgrowth or bile acid malabsorption in ileal resection or Crohn's disease of the ileum, the 14C-lactose breath test in lactase deficiency, whereas the 14C-tripalmitin test seems less helpful in the diagnosis of fat malabsorption. A 14C-aminopyrine breath test may turn out to be a simple and valuable liver function test. Oral loading tests with breath analysis of H2 have shown to be helpful in the diagnosis of carbohydrate malabsorption, determination of intestinal transit time and intestinal gas production. Due to technical reasons (gas-chromatographie analysis) H2-breath analysis is still limited to research centers. Despite low radiation doses after oral administration of 14C-labelled compounds oral loading tests with H2- or 13C-analysis might be preferable in the future.

  1. Breath ammonia measurement in Helicobacter pylori infection.

    PubMed

    Kearney, David J; Hubbard, Todd; Putnam, David

    2002-11-01

    Our aim was to define the utility of breath ammonia measurement in assessing Helicobacter pylori infection. Volunteers breathed into a device containing three fiberoptic NH3 sensors at baseline and after ingesting 300 mg of urea. Breath ammonia levels were compared to the [14C]urea breath test. Thirteen subjects were tested. Before urea ingestion, H. pylori-positive subjects had significantly lower breath ammonia levels than negative subjects (mean +/- SD, 0.04 ppm +/- 0.09 vs 0.49 ppm +/- 0.24, P = 0.002) and had a significantly greater increases in breath ammonia after urea ingestion (range 198-1,494% vs 6-98%). One H. pylori-positive subject underwent treatment and breath ammonia levels shifted from the pattern seen in positive subjects to that seen in negative subjects. In conclusion, breath ammonia measurement for H. Pylori-positive and negative subjects showed distinct patterns. Breath ammonia measurement may be feasible as a diagnostic test for H. pylori.

  2. Calculating rhythmicity of infant breathing using wavelets

    NASA Astrophysics Data System (ADS)

    Macey, Katherine E.; Page, Wyatt H.; Harper, Ronald M.; Macey, Paul M.; Ford, Rodney P. K.

    2000-12-01

    Breathing signals are one set of physiological data that may provide information regarding the mechanisms that cause SIDS. Isolated breathing pauses have been implicated in fatal events. Other features of interest include slow amplitude modulation of the breathing signal, a phenomenon whose origin is unclear, and periodic breathing. The latter describes a repetitive series of apnea, and may be considered an extreme manifestation of amplitude modulation with successive cessations of breathing. Rhythmicity is defined to assess the impact of amplitude modulation on breathing signals and describes the extent to which frequency components remain constant for the duration of the signal. The wavelet transform was used to identify sections of constant frequency components within signals. Rhythmicity can be evaluated for all the frequency components in a signal, for individual frequencies. The rhythmicity of eight breathing epochs from sleeping infants at high and low risk for SIDS was calculated. Initial results show breathing from infants at high risk for SIDS exhibits greater rhythmicity of modulating frequencies than breathing from low risk infants.

  3. 42 CFR 84.79 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing gas; minimum requirements. 84.79 Section...-Contained Breathing Apparatus § 84.79 Breathing gas; minimum requirements. (a) Breathing gas used to supply... respiratory tract irritating compounds. (c) Compressed, gaseous breathing air shall meet the...

  4. 42 CFR 84.79 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing gas; minimum requirements. 84.79 Section...-Contained Breathing Apparatus § 84.79 Breathing gas; minimum requirements. (a) Breathing gas used to supply... respiratory tract irritating compounds. (c) Compressed, gaseous breathing air shall meet the...

  5. 42 CFR 84.85 - Breathing bags; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing bags; minimum requirements. 84.85 Section...-Contained Breathing Apparatus § 84.85 Breathing bags; minimum requirements. (a) Breathing bags shall have.... (b) Breathing bags shall be constructed of materials which are flexible and resistant to...

  6. 42 CFR 84.85 - Breathing bags; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing bags; minimum requirements. 84.85 Section...-Contained Breathing Apparatus § 84.85 Breathing bags; minimum requirements. (a) Breathing bags shall have.... (b) Breathing bags shall be constructed of materials which are flexible and resistant to...

  7. 42 CFR 84.85 - Breathing bags; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing bags; minimum requirements. 84.85 Section...-Contained Breathing Apparatus § 84.85 Breathing bags; minimum requirements. (a) Breathing bags shall have.... (b) Breathing bags shall be constructed of materials which are flexible and resistant to...

  8. 42 CFR 84.85 - Breathing bags; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing bags; minimum requirements. 84.85 Section...-Contained Breathing Apparatus § 84.85 Breathing bags; minimum requirements. (a) Breathing bags shall have.... (b) Breathing bags shall be constructed of materials which are flexible and resistant to...

  9. 42 CFR 84.79 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing gas; minimum requirements. 84.79 Section...-Contained Breathing Apparatus § 84.79 Breathing gas; minimum requirements. (a) Breathing gas used to supply... respiratory tract irritating compounds. (c) Compressed, gaseous breathing air shall meet the...

  10. 42 CFR 84.79 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing gas; minimum requirements. 84.79 Section...-Contained Breathing Apparatus § 84.79 Breathing gas; minimum requirements. (a) Breathing gas used to supply... respiratory tract irritating compounds. (c) Compressed, gaseous breathing air shall meet the...

  11. 42 CFR 84.79 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing gas; minimum requirements. 84.79 Section...-Contained Breathing Apparatus § 84.79 Breathing gas; minimum requirements. (a) Breathing gas used to supply... respiratory tract irritating compounds. (c) Compressed, gaseous breathing air shall meet the...

  12. 42 CFR 84.85 - Breathing bags; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing bags; minimum requirements. 84.85 Section...-Contained Breathing Apparatus § 84.85 Breathing bags; minimum requirements. (a) Breathing bags shall have.... (b) Breathing bags shall be constructed of materials which are flexible and resistant to...

  13. 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 ...

  14. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Compressed breathing gas and liquefied breathing gas containers; minimum requirements. 84.81 Section 84.81 Public Health PUBLIC HEALTH SERVICE... liquefied breathing gas containers shall meet the minimum requirements of the Department of...

  15. 42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Compressed breathing gas and liquefied breathing gas containers; minimum requirements. 84.81 Section 84.81 Public Health PUBLIC HEALTH SERVICE... liquefied breathing gas containers shall meet the minimum requirements of the Department of...

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. A simple model implementation to measure breath by breath the VO2 and VCO2 by the indirect calorimetry technique.

    PubMed

    Cadena, M; Sacristan, E; Infante, O; Rodriguez, F; Escalante, B; Pérez, P; Azpiroz, J

    2006-01-01

    This paper proposes a discrete random time series modeling for the VO2 and VCO2 measurement in the indirect calorimetry technique (ICT). Mathematical equations are developed in order to establish clear differences between the breath-by-breath and mixing chamber measurement based calorimeters. This simple model offers not only a physiological ICT definition approach but also defines the idea of VO2 and VCO2 short-term variability information for research. The preliminary results show a new physiological information when a computer oriented algorithm model implementation was applied to a data acquisition system in order to obtain the power spectrum analysis from a typical observation subject submitted to the clino-ortho maneuver.

  3. 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…

  4. 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.

  5. 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...

  6. Application of LaserBreath-001 for breath acetone measurement in subjects with diabetes mellitus

    NASA Astrophysics Data System (ADS)

    Wang, Zhennan; Sun, Meixiu; Chen, Zhuying; Zhao, Xiaomeng; Li, Yingxin; Wang, Chuji

    2016-11-01

    Breath acetone is a promising biomarker of diabetes mellitus. With an integrated standalone, on-site cavity ringdown breath acetone analyzer, LaserBreath-001, we tested breath samples from 23 type 1 diabetic (T1D) patients, 312 type 2 diabetic (T2D) patients, 52 healthy subjects. In the cross-sectional studies, the obtained breath acetone concentrations were higher in the diabetic subjects compared with those in the control group. No correlation between breath acetone and simultaneous BG was observed in the T1D, T2D, and healthy subjects. A moderate positive correlation between the mean individual breath acetone concentrations and the mean individual BG levels was observed in the 20 T1D patients without ketoacidosis. In a longitudinal study, the breath acetone concentrations in a T1D patient with ketoacidosis decreased significantly and remained stable during the 5-day hospitalization. The results from a relatively large number of subjects tested indicate that an elevated mean breath acetone concentration exists in diabetic patients in general. Although many physiological parameters affect breath acetone concentrations, fast (<1 min) and on site breath acetone measurement can be used for diabetic screening and management under a specifically controlled condition.

  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. Autonomic cardiovascular and respiratory control during prolonged spaceflights aboard the International Space Station.

    PubMed

    Baevsky, Roman M; Baranov, Victor M; Funtova, Irina I; Diedrich, André; Pashenko, Andrey V; Chernikova, Anja G; Drescher, Jürgen; Jordan, Jens; Tank, Jens

    2007-07-01

    Impaired autonomic control represents a cardiovascular risk factor during long-term spaceflight. Little has been reported on blood pressure (BP), heart rate (HR), and heart rate variability (HRV) during and after prolonged spaceflight. We tested the hypothesis that cardiovascular control remains stable during prolonged spaceflight. Electrocardiography, photoplethysmography, and respiratory frequency (RF) were assessed in eight male cosmonauts (age 41-50 yr, body-mass index of 22-28 kg/m2) during long-term missions (flight lengths of 162-196 days). Recordings were made 60 and 30 days before the flight, every 4 wk during flight, and on days 3 and 6 postflight during spontaneous and controlled respiration. Orthostatic testing was performed pre- and postflight. RF and BP decreased during spaceflight (P < 0.05). Mean HR and HRV in the low- and high-frequency bands did not change during spaceflight. However, the individual responses were different and correlated with preflight values. Pulse-wave transit time decreased during spaceflight (P < 0.05). HRV reached during controlled respiration (6 breaths/min) decreased in six and increased in one cosmonaut during flight. The most pronounced changes in HR, BP, and HRV occurred after landing. The decreases in BP and RF combined with stable HR and HRV during flight suggest functional adaptation rather than pathological changes. Pulse-wave transit time shortening in our study is surprising and may reflect cardiac output redistribution in space. The decrease in HRV during controlled respiration (6 breaths/min) indicates reduced parasympathetic reserve, which may contribute to postflight disturbances.

  9. 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.

  10. Fetal breathing movements: antepartum monitoring of fetal condition.

    PubMed

    Manning, F A; Platt, L D

    1979-08-01

    Until recently, the relative inaccessibility of the human fetus to physical assessment has made antepartum assessment of its condition difficult. The development of methods for accurate antepartum fetal heart rate monitoring and the subsequent study of heart rate responses to various stimuli have resulted in a significant improvement in accuracy of antepartum fetal surveillance. The development of real time B-mode ultrasound enables the clinician to assess many additional fetal biophysical variables including fetal breathing movements. In our observations, the combination of heart rate and fetal breathing assessment has produced a significant improvement in differentiating the normal from the compromised fetus. The addition of other biophysical variables (tone, movements and amniotic fluid volume) have further refined the ability to identify the fetus at risk. At this point, we have evaluated only a few of many possible variables. It seems probable that, as other fetal biophysical variables are included with the overall assessment, for example fetal reflexes or fetal biophysical response to exogenous stimuli, the identification of the fetus at risk and the quantitation of the magnitude of risk will become increasingly more precise.

  11. 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

    2015-07-08

    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.

  12. Device-Guided Breathing for Hypertension: a Summary Evidence Review.

    PubMed

    Mahtani, Kamal R; Beinortas, Tumas; Bauza, Karolis; Nunan, David

    2016-04-01

    Persistently raised blood pressure is one of the major risk factors for diseases such as myocardial infarction and stroke. Uncontrolled hypertension is also associated with high rates of mortality, particularly in middle and high-income countries. Lifestyle factors such as poor diet, obesity, physical inactivity and smoking are all thought to contribute to the development of hypertension. As a result, the management of hypertension should begin with modifying these lifestyle factors. Beyond this, drug interventions are used as the predominant form of management. However, adherence to medications can be highly variable, medication side effects are common, and may require regular monitoring or, in some individuals may be ineffective. Therefore, additional non-pharmacologic interventions that lower blood pressure may be advantageous when combined with lifestyle modifications. Such interventions may include relaxation therapies such as slow breathing exercises, which can be initiated by means of specific devices. The technique of device-guided breathing (DGB) has been considered by guideline developers in the management of hypertension. One specific device, the Resperate, has received US FDA and UK NHS approval over the last few years. In this review, we summarise the evidence base on efficacy and find that although some clinical trials exist that demonstrate a BP-lowering effect, others do not. There is currently insufficient evidence from pooled data to recommend the routine use of device-guided breathing in hypertensive patients.

  13. 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.

  14. 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

  15. 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.

  16. Breath hydrogen excretion in infants with colic.

    PubMed

    Miller, J J; McVeagh, P; Fleet, G H; Petocz, P; Brand, J C

    1989-05-01

    Breath hydrogen excretion as an index of incomplete lactose absorption was measured in 118 healthy infants who were either breast fed or given a formula feed containing lactose, some of whom had colic. Infants with colic (n = 65) were selected on the basis of the mother's report of a history of inconsolable crying lasting several hours each day. Infants in the control group (n = 53) were not reported to cry excessively by their mothers. Breath samples were collected using a face mask sampling device preprandially, and 90 and 150 minutes after the start of a feed. Normalised breath hydrogen concentrations were higher in the group with colic than in the control group at each time point. The median maximum breath hydrogen concentration in the colic group was 29 ppm, and in the control group 11 ppm. The percentage of infants with incomplete lactose absorption (breath hydrogen concentration more than 20 ppm) in the colic group was 62% compared with 32% in the control group. The clinical importance of the observed association between increased breath hydrogen excretion and infantile colic remains to be determined. Increased breath hydrogen excretion indicative of incomplete lactose absorption may be either a cause or an effect of colic in infants.

  17. Breathing and sleep at high altitude.

    PubMed

    Ainslie, Philip N; Lucas, Samuel J E; Burgess, Keith R

    2013-09-15

    We provide an updated review on the current understanding of breathing and sleep at high altitude in humans. We conclude that: (1) progressive changes in pH initiated by the respiratory alkalosis do not underlie early (<48 h) ventilatory acclimatization to hypoxia (VAH) because this still proceeds in the absence of such alkalosis; (2) for VAH of longer duration (>48 h), complex cellular and neurochemical re-organization occurs both in the peripheral chemoreceptors as well as within the central nervous system. The latter is likely influenced by central acid-base changes secondary to the extent of the initial respiratory responses to initial exposure to high altitude; (3) sleep at high altitude is disturbed by various factors, but principally by periodic breathing; (4) the extent of periodic breathing during sleep at altitude intensifies with duration and severity of exposure; (5) complex interactions between hypoxic-induced enhancement in peripheral and central chemoreflexes and cerebral blood flow--leading to higher loop gain and breathing instability--underpin this development of periodic breathing during sleep; (6) because periodic breathing may elevate rather than reduce mean SaO2 during sleep, this may represent an adaptive rather than maladaptive response; (7) although oral acetazolamide is an effective means to reduce periodic breathing by 50-80%, recent studies using positive airway pressure devices to increase dead space, hyponotics and theophylline are emerging but appear less practical and effective compared to acetazolamide. Finally, we suggest avenues for future research, and discuss implications for understanding sleep pathology.

  18. 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.

  19. Effects of slow deep breathing at high altitude on oxygen saturation, pulmonary and systemic hemodynamics.

    PubMed

    Bilo, Grzegorz; Revera, Miriam; Bussotti, Maurizio; Bonacina, Daniele; Styczkiewicz, Katarzyna; Caldara, Gianluca; Giglio, Alessia; Faini, Andrea; Giuliano, Andrea; Lombardi, Carolina; Kawecka-Jaszcz, Kalina; Mancia, Giuseppe; Agostoni, Piergiuseppe; Parati, Gianfranco

    2012-01-01

    Slow deep breathing improves blood oxygenation (Sp(O2)) and affects hemodynamics in hypoxic patients. We investigated the ventilatory and hemodynamic effects of slow deep breathing in normal subjects at high altitude. We collected data in healthy lowlanders staying either at 4559 m for 2-3 days (Study A; N = 39) or at 5400 m for 12-16 days (Study B; N = 28). Study variables, including Sp(O2) and systemic and pulmonary arterial pressure, were assessed before, during and after 15 minutes of breathing at 6 breaths/min. At the end of slow breathing, an increase in Sp(O2) (Study A: from 80.2±7.7% to 89.5±8.2%; Study B: from 81.0±4.2% to 88.6±4.5; both p<0.001) and significant reductions in systemic and pulmonary arterial pressure occurred. This was associated with increased tidal volume and no changes in minute ventilation or pulmonary CO diffusion. Slow deep breathing improves ventilation efficiency for oxygen as shown by blood oxygenation increase, and it reduces systemic and pulmonary blood pressure at high altitude but does not change pulmonary gas diffusion.

  20. Activity-adjusted 24-hour ambulatory blood pressure and cardiac remodeling in children with sleep disordered breathing.

    PubMed

    Amin, Raouf; Somers, Virend K; McConnell, Keith; Willging, Paul; Myer, Charles; Sherman, Marc; McPhail, Gary; Morgenthal, Ashley; Fenchel, Matthew; Bean, Judy; Kimball, Thomas; Daniels, Stephen

    2008-01-01

    Questions remain as to whether pediatric sleep disordered breathing increases the risk for elevated blood pressure and blood pressure-dependent cardiac remodeling. We tested the hypothesis that activity-adjusted morning blood pressure surge, blood pressure load, and diurnal and nocturnal blood pressure are significantly higher in children with sleep disordered breathing than in healthy controls and that these blood pressure parameters relate to left ventricular remodeling. 24-hour ambulatory blood pressure parameters were compared between groups. The associations between blood pressure and left ventricular relative wall thickness and mass were measured. 140 children met the inclusion criteria. In children with apnea hypopnea index <5 per hour, a significant difference from controls was the morning blood surge. Significant increases in blood pressure surge, blood pressure load, and in 24-hour ambulatory blood pressure were evident in those whom the apnea hypopnea index exceeded 5 per hour. Sleep disordered breathing and body mass index had similar effect on blood pressure parameters except for nocturnal diastolic blood pressure, where sleep disordered breathing had a significantly greater effect than body mass index. Diurnal and nocturnal systolic blood pressure, diastolic blood pressure, and mean arterial blood pressure predicted the changes in left ventricular relative wall thickness. Therefore, sleep disordered breathing in children who are otherwise healthy is independently associated with an increase in morning blood pressure surge, blood pressure load, and 24-hour ambulatory blood pressure. The association between left ventricular remodeling and 24-hour blood pressure highlights the role of sleep disordered breathing in increasing cardiovascular morbidity.

  1. An adaptive breath sampler for use with human subjects with an impaired respiratory function.

    PubMed

    Basanta, M; Koimtzis, T; Singh, D; Wilson, I; Thomas, C L P

    2007-02-01

    An adaptive sampler for collecting 2.5 dm(3) samples of exhaled air from human subjects with an impaired respiratory function is described. Pressure in the upper respiratory tract is continuously monitored and the data used to control an automated system to collect select portions of the expired breathing cycle onto a mixed bed Tenax(trade mark) and Carbotrap(trade mark) adsorbent trap for analysis by GC-MS. The sampling approach is intended for use in metabolomic profiling of volatiles in human breath at concentrations greater than microg m(-3). The importance of experimental reproducibility in metabolomic data is emphasised and consequently a high purity air supply is used to maintain a stable exogenous volatile organic compound profile at concentrations in the range 5 to 30 microg m(-3). The results of a 90 day stability study showed that exogenous VOCs were maintained at significantly lower levels (40 times lower for isopropyl alcohol) and with significantly higher reproducibility (80 times lower standard deviation for isopropyl alcohol) than would have been be the case if ambient air had been used. The sampling system was evaluated with healthy controls alongside subjects with chronic obstructive pulmonary disease. Subjects were able to breathe normally with control subjects observed to breathe at a rate of 9 to 17 breaths per minute, compared to 16 to 30 breaths per minute for subjects with COPD. This study presents, for the first time, observations and estimates of intra-subject breath sample reproducibility from human subjects. These reproducibility studies indicated that VOCs in exhaled breath exhibit a variety of dynamic behaviours, with some species recovered with a RSD <30%, while other species were observed to have significantly more variable concentrations, 30 to 130% RSD. The approach was also demonstrated to reliably differentiate the differences in the VOC profiles between alveolar and dead space air.

  2. 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.

  3. 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.

  4. Effect of deep breathing at six breaths per minute on the frequency of premature ventricular complexes.

    PubMed

    Prakash, E Sankaranarayanan; Ravindra, Pattanashetty N; Madanmohan; Anilkumar, R; Balachander, J

    2006-08-28

    Although the effect of reflex increase in vagal tone on the frequency of premature ventricular complexes (PVC) is known, the effect of timed deep breathing on the frequency of PVC has not been reported. We serendipitously discovered that deep breathing at six breaths per minute abolished PVC in an 18-year-old female with frequent PVC, anxiety, and palpitations. In five of a series of 10 consecutive patients with frequent (> or = 10/min) unifocal PVC, deep breathing at 6 breaths/min reduced the frequency of PVC by at least 50%. This is possibly due to increased vagal modulation of sinoatrial and atrioventricular node. However, factors predicting the response to deep breathing, and the mechanisms involved need to be studied in a larger number of patients.

  5. 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...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  6. 14 CFR 25.1439 - Protective breathing equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Protective breathing equipment. 25.1439... Protective breathing equipment. (a) Fixed (stationary, or built in) protective breathing equipment must be installed for the use of the flightcrew, and at least one portable protective breathing equipment shall...

  7. 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....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being...

  8. 42 CFR 84.141 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing gas; minimum requirements. 84.141 Section... Respirators § 84.141 Breathing gas; minimum requirements. (a) Breathing gas used to supply supplied-air respirators shall be respirable breathing air and contain no less than 19.5 volume-percent of oxygen....

  9. 42 CFR 84.141 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing gas; minimum requirements. 84.141 Section... Respirators § 84.141 Breathing gas; minimum requirements. (a) Breathing gas used to supply supplied-air respirators shall be respirable breathing air and contain no less than 19.5 volume-percent of oxygen....

  10. 42 CFR 84.88 - Breathing bag test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing bag test. 84.88 Section 84.88 Public... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.88 Breathing bag test. (a) Breathing bags will be tested in an air atmosphere saturated...

  11. 21 CFR 868.5250 - Breathing circuit circulator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breathing circuit circulator. 868.5250 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5250 Breathing circuit circulator. (a) Identification. A breathing circuit circulator is a turbine device that is attached to a closed breathing...

  12. 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....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being...

  13. 42 CFR 84.141 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing gas; minimum requirements. 84.141 Section... Respirators § 84.141 Breathing gas; minimum requirements. (a) Breathing gas used to supply supplied-air respirators shall be respirable breathing air and contain no less than 19.5 volume-percent of oxygen....

  14. 21 CFR 868.5270 - Breathing system heater.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breathing system heater. 868.5270 Section 868.5270...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5270 Breathing system heater. (a) Identification. A breathing system heater is a device that is intended to warm breathing gases before they...

  15. 42 CFR 84.88 - Breathing bag test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing bag test. 84.88 Section 84.88 Public... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.88 Breathing bag test. (a) Breathing bags will be tested in an air atmosphere saturated...

  16. 14 CFR 121.337 - Protective breathing equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Protective breathing equipment. 121.337... Protective breathing equipment. (a) The certificate holder shall furnish approved protective breathing equipment (PBE) meeting the equipment, breathing gas, and communication requirements contained in...

  17. 14 CFR 25.1439 - Protective breathing equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Protective breathing equipment. 25.1439... Protective breathing equipment. (a) Fixed (stationary, or built in) protective breathing equipment must be installed for the use of the flightcrew, and at least one portable protective breathing equipment shall...

  18. 14 CFR 121.337 - Protective breathing equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Protective breathing equipment. 121.337... Protective breathing equipment. (a) The certificate holder shall furnish approved protective breathing equipment (PBE) meeting the equipment, breathing gas, and communication requirements contained in...

  19. 21 CFR 868.5250 - Breathing circuit circulator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing circuit circulator. 868.5250 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5250 Breathing circuit circulator. (a) Identification. A breathing circuit circulator is a turbine device that is attached to a closed breathing...

  20. 21 CFR 868.5250 - Breathing circuit circulator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing circuit circulator. 868.5250 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5250 Breathing circuit circulator. (a) Identification. A breathing circuit circulator is a turbine device that is attached to a closed breathing...

  1. 21 CFR 868.5250 - Breathing circuit circulator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breathing circuit circulator. 868.5250 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5250 Breathing circuit circulator. (a) Identification. A breathing circuit circulator is a turbine device that is attached to a closed breathing...

  2. 21 CFR 868.5270 - Breathing system heater.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breathing system heater. 868.5270 Section 868.5270...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5270 Breathing system heater. (a) Identification. A breathing system heater is a device that is intended to warm breathing gases before they...

  3. 42 CFR 84.141 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing gas; minimum requirements. 84.141 Section... Respirators § 84.141 Breathing gas; minimum requirements. (a) Breathing gas used to supply supplied-air respirators shall be respirable breathing air and contain no less than 19.5 volume-percent of oxygen....

  4. 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...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  5. 42 CFR 84.88 - Breathing bag test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing bag test. 84.88 Section 84.88 Public... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.88 Breathing bag test. (a) Breathing bags will be tested in an air atmosphere saturated...

  6. 21 CFR 868.5270 - Breathing system heater.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing system heater. 868.5270 Section 868.5270...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5270 Breathing system heater. (a) Identification. A breathing system heater is a device that is intended to warm breathing gases before they...

  7. 42 CFR 84.88 - Breathing bag test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing bag test. 84.88 Section 84.88 Public... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.88 Breathing bag test. (a) Breathing bags will be tested in an air atmosphere saturated...

  8. 14 CFR 121.337 - Protective breathing equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Protective breathing equipment. 121.337... Protective breathing equipment. (a) The certificate holder shall furnish approved protective breathing equipment (PBE) meeting the equipment, breathing gas, and communication requirements contained in...

  9. 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....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being...

  10. 42 CFR 84.88 - Breathing bag test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing bag test. 84.88 Section 84.88 Public... RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.88 Breathing bag test. (a) Breathing bags will be tested in an air atmosphere saturated...

  11. 21 CFR 868.5270 - Breathing system heater.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing system heater. 868.5270 Section 868.5270...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5270 Breathing system heater. (a) Identification. A breathing system heater is a device that is intended to warm breathing gases before they...

  12. 21 CFR 868.5250 - Breathing circuit circulator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing circuit circulator. 868.5250 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5250 Breathing circuit circulator. (a) Identification. A breathing circuit circulator is a turbine device that is attached to a closed breathing...

  13. 14 CFR 121.337 - Protective breathing equipment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Protective breathing equipment. 121.337... Protective breathing equipment. (a) The certificate holder shall furnish approved protective breathing equipment (PBE) meeting the equipment, breathing gas, and communication requirements contained in...

  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...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  15. 21 CFR 868.5270 - Breathing system heater.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing system heater. 868.5270 Section 868.5270...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5270 Breathing system heater. (a) Identification. A breathing system heater is a device that is intended to warm breathing gases before they...

  16. 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....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being...

  17. 42 CFR 84.141 - Breathing gas; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing gas; minimum requirements. 84.141 Section... Respirators § 84.141 Breathing gas; minimum requirements. (a) Breathing gas used to supply supplied-air respirators shall be respirable breathing air and contain no less than 19.5 volume-percent of oxygen....

  18. 14 CFR 121.337 - Protective breathing equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Protective breathing equipment. 121.337... Protective breathing equipment. (a) The certificate holder shall furnish approved protective breathing equipment (PBE) meeting the equipment, breathing gas, and communication requirements contained in...

  19. 14 CFR 25.1439 - Protective breathing equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Protective breathing equipment. 25.1439... Protective breathing equipment. (a) Fixed (stationary, or built in) protective breathing equipment must be installed for the use of the flightcrew, and at least one portable protective breathing equipment shall...

  20. 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....5 times its maximum working pressure; (2) Each breathing supply hose assembly, prior to being...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. Breathing Problems - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Supplements Videos & Tools You Are Here: Home → Multiple Languages → All Health Topics → Breathing Problems URL of this page: https://medlineplus.gov/languages/breathingproblems.html Other topics A-Z A B ...

  12. 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.

  13. Healthy Living: Helping Your Child Breathe Easier

    MedlinePlus

    ... cystic fibrosis. In terms of childhood disease, the respiratory system is the most critical. Here are some tips ... or “irritants” can cause the muscles of the respiratory system to contract, narrowing the airways. Breathing through these ...

  14. Breathing exercises for adults with asthma.

    PubMed

    2015-11-01

    Asthma is a common long-term condition that remains poorly controlled in many people despite the availability of pharmacological interventions, evidence-based treatment guidelines and care pathways.(1) There is considerable public interest in the use of non-pharmacological approaches for the treatment of asthma.(2) A survey of people with asthma reported that many have used complementary and alternative medicine, often without the knowledge of their clinical team.(3) Such interventions include breathing techniques, herbal products, homeopathy and acupuncture. The role of breathing exercises within the management of asthma has been controversial, partly because early claims of effectiveness were exaggerated.(4) UK national guidance and international guidelines on the management of asthma have included the option of breathing exercise programmes as an adjuvant to pharmacological treatment.(5,6) Here we discuss the types of breathing exercises used and review the evidence for their effectiveness.

  15. Nine months in space: effects on human autonomic cardiovascular regulation.

    PubMed

    Cooke, W H; Ames JE, I V; Crossman, A A; Cox, J F; Kuusela, T A; Tahvanainen, K U; Moon, L B; Drescher, J; Baisch, F J; Mano, T; Levine, B D; Blomqvist, C G; Eckberg, D L

    2000-09-01

    We studied three Russian cosmonauts to better understand how long-term exposure to microgravity affects autonomic cardiovascular control. We recorded the electrocardiogram, finger photoplethysmographic pressure, and respiratory flow before, during, and after two 9-mo missions to the Russian space station Mir. Measurements were made during four modes of breathing: 1) uncontrolled spontaneous breathing; 2) stepwise breathing at six different frequencies; 3) fixed-frequency breathing; and 4) random-frequency breathing. R wave-to-R wave (R-R) interval standard deviations decreased in all and respiratory frequency R-R interval spectral power decreased in two cosmonauts in space. Two weeks after the cosmonauts returned to Earth, R-R interval spectral power was decreased, and systolic pressure spectral power was increased in all. The transfer function between systolic pressures and R-R intervals was reduced in-flight, was reduced further the day after landing, and had not returned to preflight levels by 14 days after landing. Our results suggest that long-duration spaceflight reduces vagal-cardiac nerve traffic and decreases vagal baroreflex gain and that these changes may persist as long as 2 wk after return to Earth.

  16. Improvement in Mortality Risk Prediction Following Percutaneous Coronary Intervention Through Addition of a “Compassionate Use” Variable to the National Cardiovascular Data Registry CathPCI® Dataset: A Study from the Massachusetts Angioplasty Registry

    PubMed Central

    Resnic, Frederic S.; Normand, Sharon-Lise T.; Piemonte, Thomas C.; Shubrooks, Samuel J.; Zelevinsky, Katya; Lovett, Ann; Ho, Kalon K.L.

    2011-01-01

    Objectives This study investigated the impact of adding novel elements to models predicting in-hospital mortality following percutaneous coronary interventions (PCIs). Background Massachusetts (MA) mandated public reporting of hospital-specific PCI mortality in 2003. In 2006, a physician advisory group recommended adding to the prediction models three attributes not collected by the National Cardiovascular Data Registry instrument. These “compassionate use” (CU) features included coma on presentation, active hemodynamic support during PCI, and cardiopulmonary resuscitation at PCI initiation. Methods From October 2005 through September 2007, PCI was performed during 29,784 admissions in MA non-federal hospitals. Of these, 5,588 involved patients with ST segment elevation myocardial infarction or cardiogenic shock. Cases with CU criteria identified were adjudicated by trained physician reviewers. Regression models with and without the CU composite variable (presence of any of the 3 features) were compared using areas under the receiver operator characteristic curves (AUC). Results Unadjusted mortality in this high-risk subset was 5.7%. Among these admissions, 96 (1.7%) had at least one CU feature, with 69.8% mortality. The adjusted odds ratio for in-hospital death for CU PCIs (vs. no CU criteria) was 27.3 (95% CI 14.5–47.6). Discrimination of the model improved after including CU, with AUC increasing from 0.87 to 0.90 (p<0.01), while goodness of fit was preserved. Conclusions A small proportion of patients at extreme risk for post-PCI mortality can be identified using pre-procedural factors not routinely collected, but that heighten predictive accuracy. Such improvements in model performance may result in greater confidence in reporting of risk-adjusted PCI outcomes. PMID:21329835

  17. Controlled Frequency Breathing Reduces Inspiratory Muscle Fatigue.

    PubMed

    Burtch, Alex R; Ogle, Ben T; Sims, Patrick A; Harms, Craig A; Symons, Thorburn B; Folz, Rodney J; Zavorsky, Gerald S

    2016-08-16

    Controlled frequency breathing (CFB) is a common swim training modality involving holding one's breath for about 7 to 10 strokes before taking another breath. We sought to examine the effects of CFB training on reducing respiratory muscle fatigue. Competitive college swimmers were randomly divided into either the CFB group that breathed every 7 to 10 strokes, or a control group that breathed every 3-4 strokes. Twenty swimmers completed the study. The training intervention included 5-6 weeks (16 sessions) of 12x50-m repetitions with breathing 8-10 breaths per 50m (control group), or 2-3 breaths per 50-m (CFB group). Inspiratory muscle fatigue was defined as the decrease in maximal inspiratory mouth-pressure (MIP) between rest and 46s after a 200 yard free-style swimming race [115s (SD 7)]. Aerobic capacity, pulmonary diffusing capacity, and running economy were also measured pre and post-training. Pooled results demonstrated a 12% decrease in MIP at 46s post-race [-15 (SD 14) cm H2O, Effect size = -0.48, p < 0.01]. After four weeks of training, only the CFB group prevented a decline in MIP values pre to 46 s post-race [-2 (13) cm H2O, p > 0.05]. However, swimming performance, aerobic capacity, pulmonary diffusing capacity, and running economy did not improve (p > 0.05) post-training in either group. In conclusion, CFB training appears to prevent inspiratory muscle fatigue yet no difference was found in performance outcomes.

  18. [Sleep-disordered breathing and dentofacial development].

    PubMed

    Cobo Plana, Juan; de Carlos Villafranca, Félix

    2010-12-01

    Humans breathe an average of 20 times per minute, totalling about 30,000 times a day, and swallow nearly 2,000 times a day. These functions are vital for life. Growing children must adapt their developing structures to various destabilizing processes. When these factors outweigh the compensatory mechanisms, growth may become unbalanced by favoring the development of pathological processes such as sleep breathing disorders.

  19. Exhaled breath analysis for lung cancer

    PubMed Central

    Sutedja, Tom G.; Zimmerman, Paul V.

    2013-01-01

    Early diagnosis of lung cancer results in improved survival compared to diagnosis with more advanced disease. Early disease is not reliably indicated by symptoms. Because investigations such as bronchoscopy and needle biopsy have associated risks and substantial costs, they are not suitable for population screening. Hence new easily applicable tests, which can be used to screen individuals at risk, are required. Biomarker testing in exhaled breath samples is a simple, relatively inexpensive, non-invasive approach. Exhaled breath contains volatile and non-volatile organic compounds produced as end-products of metabolic processes and the composition of such compounds varies between healthy subjects and subjects with lung cancer. Many studies have analysed the patterns of these compounds in exhaled breath. In addition studies have also reported that the exhaled breath condensate (EBC) can reveal gene mutations or DNA abnormalities in patients with lung cancer. This review has summarised the scientific evidence demonstrating that lung cancer has distinct chemical profiles in exhaled breath and characteristic genetic changes in EBC. It is not yet possible to accurately identify individuals with lung cancer in at risk populations by any of these techniques. However, analysis of both volatile organic compounds in exhaled breath and of EBC have great potential to become clinically useful diagnostic and screening tools for early stage lung cancer detection. PMID:24163746

  20. Swimming in air-breathing fishes.

    PubMed

    Lefevre, S; Domenici, P; McKenzie, D J

    2014-03-01

    Fishes with bimodal respiration differ in the extent of their reliance on air breathing to support aerobic metabolism, which is reflected in their lifestyles and ecologies. Many freshwater species undertake seasonal and reproductive migrations that presumably involve sustained aerobic exercise. In the six species studied to date, aerobic exercise in swim flumes stimulated air-breathing behaviour, and there is evidence that surfacing frequency and oxygen uptake from air show an exponential increase with increasing swimming speed. In some species, this was associated with an increase in the proportion of aerobic metabolism met by aerial respiration, while in others the proportion remained relatively constant. The ecological significance of anaerobic swimming activities, such as sprinting and fast-start manoeuvres during predator-prey interactions, has been little studied in air-breathing fishes. Some species practise air breathing during recovery itself, while others prefer to increase aquatic respiration, possibly to promote branchial ion exchange to restore acid-base balance, and to remain quiescent and avoid being visible to predators. Overall, the diversity of air-breathing fishes is reflected in their swimming physiology as well, and further research is needed to increase the understanding of the differences and the mechanisms through which air breathing is controlled and used during exercise.

  1. 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.

  2. Monitoring breath markers under controlled conditions.

    PubMed

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

    2015-10-15

    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.

  3. 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...

  4. Cardiovascular Disease and Diabetes

    MedlinePlus

    ... Disease Venous Thromboembolism Aortic Aneurysm More Cardiovascular Disease & Diabetes Updated:Nov 4,2016 The following statistics speak ... disease. This content was last reviewed August 2015. Diabetes • Home • About Diabetes • Why Diabetes Matters Introduction Cardiovascular ...

  5. 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

  6. 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

  7. 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.

  8. Changes of autonomic nervous system function in patients with breath-holding spells treated with iron.

    PubMed

    Orii, Kenji E; Kato, Zenichiro; Osamu, Fukutomi; Funato, Michinori; Kubodera, Uniko; Inoue, Ryosuke; Shimozawa, Nobuyuki; Kondo, Naomi

    2002-05-01

    To evaluate the autonomic nervous system of patients with breath-holding spells after iron treatment, we attempted to determine whether a dysregulation of the autonomic nervous system reflexes exists in children with severe cyanotic breathholding spells. An electrocardiogram for each subject was recorded for 24 hours in the subject's home and parasympathetic activity was investigated by the fast Fourier transform method. Hematologic data and clinical symptoms of all three patients treated with iron improved and attacks of severe breath-holding spells disappeared. After iron treatment was started, the heart rate variability increased during sleep. It appears that supplementation of iron is effective in improving the dysregulation of autonomic nervous system reflexes.

  9. 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.

  10. Potential Side Effects of Unhealthy Lifestyle Choices and Health Risks on Basal and Reactive Heart Rate Variability in College Drinkers

    PubMed Central

    Udo, Tomoko; Mun, Eun-Young; Buckman, Jennifer F.; Vaschillo, Evgeny G.; Vaschillo, Bronya; Bates, Marsha E.

    2013-01-01

    Objective: Emerging adults often begin making independent lifestyle choices during college, yet the association of these choices with fundamental indicators of health and adaptability is unclear. The present study examined the relationship between health risks and neurocardiac function in college drinkers. Method: Heart rate variability (HRV) was assessed at baseline and in reaction to a paced breathing challenge in 212 college drinkers (53.8% women). Basal HRV served as a general indicator of health. Reactive HRV (during paced breathing) was used as a marker of an individual’s adaptability to challenge. The relationship of HRV to alcohol use, cigarette use, exercise, sleep, and body mass index (BMI) was assessed. Results: Greater alcohol use and less exercise were associated with lower basal HRV. BMI was unrelated to basal HRV but was negatively associated with reactive HRV during the breathing challenge. Conclusions: High levels of alcohol use and lack of exercise are negative correlates of cardiovascular and general health, even in apparently healthy college drinkers. The negative relationship between BMI and reactive HRV suggests that overweight individuals have reduced ability to psychophysiologically adapt to challenges; understanding the temporal course of this relationship is needed. This study highlights the importance of examining HRV at baseline and in response to a challenge to capture the active neurocardiac processes that contribute to health and adaptive responding. The suppressive effects of health risks on HRV are modifiable; thus, HRV may be useful in evaluating the health benefits of lifestyle change and in promoting change behaviors in college drinkers. PMID:23948539

  11. Double blind randomised controlled trial of two different breathing techniques in the management of asthma

    PubMed Central

    Slader, C A; Reddel, H K; Spencer, L M; Belousova, E G; Armour, C L; Bosnic‐Anticevich, S Z; Thien, F C K; Jenkins, C R

    2006-01-01

    Background Previous studies have shown that breathing techniques reduce short acting β2 agonist use and improve quality of life (QoL) in asthma. The primary aim of this double blind study was to compare the effects of breathing exercises focusing on shallow nasal breathing with those of non‐specific upper body exercises on asthma symptoms, QoL, other measures of disease control, and inhaled corticosteroid (ICS) dose. This study also assessed the effect of peak flow monitoring on outcomes in patients using breathing techniques. Methods After a 2 week run in period, 57 subjects were randomised to one of two breathing techniques learned from instructional videos. During the following 30 weeks subjects practised their exercises twice daily and as needed for relief of symptoms. After week 16, two successive ICS downtitration steps were attempted. The primary outcome variables were QoL score and daily symptom score at week 12. Results Overall there were no clinically important differences between the groups in primary or secondary outcomes at weeks 12 or 28. The QoL score remained unchanged (0.7 at baseline v 0.5 at week 28, p = 0.11 both groups combined), as did lung function and airway responsiveness. However, across both groups, reliever use decreased by 86% (p<0.0001) and ICS dose was reduced by 50% (p<0.0001; p>0.10 between groups). Peak flow monitoring did not have a detrimental effect on asthma outcomes. Conclusion Breathing techniques may be useful in the management of patients with mild asthma symptoms who use a reliever frequently, but there is no evidence to favour shallow nasal breathing over non‐specific upper body exercises. PMID:16517572

  12. Regulatory issues on breath tests and updates of recent advances on [13C]-breath tests.

    PubMed

    Modak, Anil S

    2013-09-01

    Over the last decade non invasive diagnostic phenotype [(13)C]-breath tests as well as tests using endogenous volatile organic compounds (VOCs) in breath have been researched extensively. However, only three breath tests have been approved by the FDA over the last 15 years. Despite the potential benefits of these companion diagnostic tests (CDx) for evaluation of drug metabolizing enzyme activities and standalone diagnostic tests for disease diagnosis to personalize medicine, the clinical and commercial development of breath tests will need to overcome a number of regulatory, financial and scientific hurdles prior to their acceptance into routine clinical practice. The regulatory agencies (FDA and EMEA) need to adapt and harmonize their approval process for companion diagnostic tests as well as standalone diagnostic breath tests for personalized medicine. The Center for Devices and Radiological Health has deemed any breath test that involves a labeled (13)C substrate/drug and a device requires a Pre Market Approval (PMA), which is analogous to an approved New Drug Application. A PMA is in effect, a private license granted to the applicant for marketing a particular medical device. Any breath test with endogenous VOCs along with a device can be approved via the 510(k) application. A number of (13)C breath tests with clinical applications have been researched recently and results have been published in reputed journals. Diagnostic companies will need to invest the necessary financial resources to develop and get regulatory approval for diagnostic breath tests capable of identifying responders/non responders for FDA approved drugs with narrow therapeutic indices (personalized medicine) or for evaluating the activity of drug metabolizing P450 polymorphic enzymes or for diagnosing diseases at an early stage or for monitoring the efficacy of medications. The financial success of these diagnostic breath tests will then depend entirely on how the test is marketed to

  13. Breath hydrogen reflects canine intestinal ischemia.

    PubMed

    Perman, J A; Waters, L A; Harrison, M R; Yee, E S; Heldt, G P

    1981-09-01

    The relationship between breath hydrogen excretion and intestinal ischemia was investigated in nine mechanically ventilated dogs under pentobarbital anesthesia. An ileal segment was isolated in situ, ligated at each end, and insufflated with hydrogen. Expired air was collected at intervals. Blood volume was reduced 30% by three successive equivalent hemorrhages 10 min apart. Local bowel ischemia was produced by clamping the blood supply to the isolated segment for 10 min. Graded hemorrhage produced step-wise reductions in breath hydrogen concentration, to 77 +/- 13, 66 +/- 15, and 35 +/- 8% (mean +/- S.E.) of baseline after the first, second, and third hemorrhages, respectively. These reductions correlated highly (r = 0.84; P less than 0.01) with declines in mean aortic blood pressure. Occlusion of blood supply caused a significant (P less than 0.025) decrease in breath hydrogen concentration and excretion to 39 +/- 14% of baseline. Termination of occlusion was followed within 2 min by a 7-fold increase in breath H2 concentration above the original baseline, probably reflecting reactive hyperemia. Breath hydrogen measurements appear to reflect functional (hemorrhagic shock-induced) and mechanical (vascular occlusion induced) enteric ischemia in dogs.

  14. Relationships between sleep-disordered breathing and blood pressure and excessive daytime sleepiness among truck drivers.

    PubMed

    Cui, Renzhe; Tanigawa, Takeshi; Sakurai, Susumu; Yamagishi, Kazumasa; Iso, Hiroyasu

    2006-08-01

    Sleep-disordered breathing is a risk factor for hypertension, cardiovascular disease and accidents in the general population, but little is known about this correlation among professional truck drivers. To examine the relationships of sleep-disordered breathing with blood pressure levels and excessive daytime sleepiness among truck drivers, we conducted a population-based cross-sectional study of 1,313 subjects aged 20-69 years registered in the Japanese Trucking Association. The 3% oxygen desaturation index was selected as an indicator of sleep-disordered breathing, representing the number of desaturation events per hour of recording time in which blood oxygen fell by > or = 3% by overnight pulse oximetry. The Epworth Sleepiness Scale was used to estimate excessive daytime sleepiness. There were significant positive associations between the 3% oxygen desaturation index levels and both diastolic blood pressure levels and Epworth Sleepiness Scale scores. The multivariate odds ratio of hypertension was 2.0 (1.1-3.6) for a 3% oxygen desaturation index of > or = 15 in reference with a 3% oxygen desaturation index of <5. This association was more evident among those aged > or = 40 years and overweight subjects. Further, the multivariate odds ratio of an Epworth Sleepiness Scale of > or = 11 was 2.3 (1.1-4.9) for a 3% oxygen desaturation index of > or =15 in reference with a 3% oxygen desaturation index of <5. This association was more evident among those aged > or =40 years. The associations of sleep-disordered breathing severity with diastolic blood pressure levels and excessive daytime sleepiness suggest the need for sleep-disordered breathing screening among truck drivers for prevention of hypertension and potential traffic accidents.

  15. 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.

  16. 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

  17. Tidal breathing patterns derived from structured light plethysmography in COPD patients compared with healthy subjects

    PubMed Central

    Motamedi-Fakhr, Shayan; Wilson, Rachel C; Iles, Richard

    2017-01-01

    Purpose Differences in tidal breathing patterns have been reported between patients with chronic obstructive pulmonary disease (COPD) and healthy individuals using traditional measurement techniques. This feasibility study examined whether structured light plethysmography (SLP) – a noncontact, light-based technique – could also detect differences in tidal breathing patterns between patients with COPD and healthy subjects. Patients and methods A 5 min period of tidal (quiet) breathing was recorded in each patient with COPD (n=31) and each healthy subject (n=31), matched for age, body mass index, and sex. For every participant, the median and interquartile range (IQR; denoting within-subject variability) of 12 tidal breathing parameters were calculated. Individual data were then combined by cohort and summarized by its median and IQR. Results After correction for multiple comparisons, inspiratory time (median tI) and its variability (IQR of tI) were lower in patients with COPD (p<0.001 and p<0.01, respectively) as were ratios derived from tI (tI/tE and tI/tTot, both p<0.01) and their variability (p<0.01 and p<0.05, respectively). IE50SLP (the ratio of inspiratory to expiratory flow at 50% tidal volume calculated from the SLP signal) was higher (p<0.001) in COPD while SLP-derived time to reach peak tidal expiratory flow over expiratory time (median tPTEFSLP/tE) was shorter (p<0.01) and considerably less variable (p<0.001). Thoraco–abdominal asynchrony was increased (p<0.05) in COPD. Conclusion These early observations suggest that, like traditional techniques, SLP is able to detect different breathing patterns in COPD patients compared with subjects with no respiratory disease. This provides support for further investigation into the potential uses of SLP in assessing clinical conditions and interventions. PMID:28096696

  18. Assessment of regional ventilation and deformation using 4D-CT imaging for healthy human lungs during tidal breathing.

    PubMed

    Jahani, Nariman; Choi, Sanghun; Choi, Jiwoong; Iyer, Krishna; Hoffman, Eric A; Lin, Ching-Long

    2015-11-15

    This study aims to assess regional ventilation, nonlinearity, and hysteresis of human lungs during dynamic breathing via image registration of four-dimensional computed tomography (4D-CT) scans. Six healthy adult humans were studied by spiral multidetector-row CT during controlled tidal breathing as well as during total lung capacity and functional residual capacity breath holds. Static images were utilized to contrast static vs. dynamic (deep vs. tidal) breathing. A rolling-seal piston system was employed to maintain consistent tidal breathing during 4D-CT spiral image acquisition, providing required between-breath consistency for physiologically meaningful reconstructed respiratory motion. Registration-derived variables including local air volume and anisotropic deformation index (ADI, an indicator of preferential deformation in response to local force) were employed to assess regional ventilation and lung deformation. Lobar distributions of air volume change during tidal breathing were correlated with those of deep breathing (R(2) ≈ 0.84). Small discrepancies between tidal and deep breathing were shown to be likely due to different distributions of air volume change in the left and the right lungs. We also demonstrated an asymmetric characteristic of flow rate between inhalation and exhalation. With ADI, we were able to quantify nonlinearity and hysteresis of lung deformation that can only be captured in dynamic images. Nonlinearity quantified by ADI is greater during inhalation, and it is stronger in the lower lobes (P < 0.05). Lung hysteresis estimated by the difference of ADI between inhalation and exhalation is more significant in the right lungs than that in the left lungs.

  19. Assessment of regional ventilation and deformation using 4D-CT imaging for healthy human lungs during tidal breathing

    PubMed Central

    Jahani, Nariman; Choi, Jiwoong; Iyer, Krishna; Hoffman, Eric A.

    2015-01-01

    This study aims to assess regional ventilation, nonlinearity, and hysteresis of human lungs during dynamic breathing via image registration of four-dimensional computed tomography (4D-CT) scans. Six healthy adult humans were studied by spiral multidetector-row CT during controlled tidal breathing as well as during total lung capacity and functional residual capacity breath holds. Static images were utilized to contrast static vs. dynamic (deep vs. tidal) breathing. A rolling-seal piston system was employed to maintain consistent tidal breathing during 4D-CT spiral image acquisition, providing required between-breath consistency for physiologically meaningful reconstructed respiratory motion. Registration-derived variables including local air volume and anisotropic deformation index (ADI, an indicator of preferential deformation in response to local force) were employed to assess regional ventilation and lung deformation. Lobar distributions of air volume change during tidal breathing were correlated with those of deep breathing (R2 ≈ 0.84). Small discrepancies between tidal and deep breathing were shown to be likely due to different distributions of air volume change in the left and the right lungs. We also demonstrated an asymmetric characteristic of flow rate between inhalation and exhalation. With ADI, we were able to quantify nonlinearity and hysteresis of lung deformation that can only be captured in dynamic images. Nonlinearity quantified by ADI is greater during inhalation, and it is stronger in the lower lobes (P < 0.05). Lung hysteresis estimated by the difference of ADI between inhalation and exhalation is more significant in the right lungs than that in the left lungs. PMID:26316512

  20. Breath testing and personal exposure--SIFT-MS detection of breath acetonitrile for exposure monitoring.

    PubMed

    Storer, Malina; Curry, Kirsty; Squire, Marie; Kingham, Simon; Epton, Michael

    2015-05-26

    Breath testing has potential for the rapid assessment of the source and impact of exposure to air pollutants. During the development of a breath test for acetonitrile using selected ion flow tube mass spectrometry (SIFT-MS) raised acetonitrile concentrations in the breath of volunteers were observed that could not be explained by known sources of exposure. Workplace/laboratory exposure to acetonitrile was proposed since this was common to the volunteers with increased breath concentrations. SIFT-MS measurements of acetonitrile in breath and air were used to confirm that an academic chemistry laboratory was the source of exposure to acetonitrile, and quantify the changes that occurred to exhaled acetonitrile after exposure. High concentrations of acetonitrile were detected in the air of the chemistry laboratory. However, concentrations in the offices were not significantly different across the campus. There was a significant difference in the exhaled acetonitrile concentrations of people who worked in the chemistry laboratories (exposed) and those who did not (non-exposed). SIFT-MS testing of air and breath made it possible to determine that occupational exposure to acetonitrile in the chemistry laboratory was the cause of increased exhaled acetonitrile. Additionally, the sensitivity was adequate to measure the changes to exhaled amounts and found that breath concentrations increased quickly with short exposure and remained increased even after periods of non-exposure. There is potential to add acetonitrile to a suite of VOCs to investigate source and impact of poor air quality.

  1. Mixed Media Filters for Aircrew Breathing Systems.

    DTIC Science & Technology

    1980-12-01

    F AD-AiLT1 382 UMPQUA RESEARCH CO MYRTLE CREEK OR F/S 6/11 I MIXED MEDIA FILTERS FOR AIRCREW BREATHING SYSTEMS. CU) IDEC 80 G V COLOMBO F33615-76-C...O603 UNCLASSIFIED SAMTR-60-27 NL C Report SAM-TR-80.27 00 lot MIXED MEDIA FILTERS FOR AIRCREW BREATHING SYSTEMS Gerald V. Colombo, M.S. Umpqua Research...Texas 78235 0 ’: 0 010 T .A NOTICES This final report was submitted by Umpqua Research Company, Myrtle Creek, Oregon 97457, under contract F33615-76-C

  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. A breathing mode for warped compactifications

    NASA Astrophysics Data System (ADS)

    Underwood, Bret

    2011-10-01

    In general warped compactifications, non-trivial backgrounds for the warp factor and the dilaton break D-dimensional diffeomorphism invariance, so that dilaton fluctuations can be gauged away completely and eaten by the metric. More specifically, the warped volume modulus and the dilaton are not independent, but combine into a single gauge-invariant degree of freedom in the lower dimensional effective theory, the warped breathing mode. This occurs for all strengths of the warping, even the weakly warped limit. This warped breathing mode appears as a natural zero mode deformation of backgrounds sourced by p-branes and affects the identification of the independent degrees of freedom of flux compactifications.

  4. 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

  5. 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

  6. Practice Variation in Spontaneous Breathing Trial Performance and Reporting

    PubMed Central

    Godard, Stephanie; Herry, Christophe; Westergaard, Paul; Scales, Nathan; Brown, Samuel M.; Burns, Karen; Mehta, Sangeeta; Jacono, Frank J.; Kubelik, Dalibor; Maziak, Donna E.; Marshall, John; Martin, Claudio; Seely, Andrew J. E.

    2016-01-01

    Background. Spontaneous breathing trials (SBTs) are standard of care in assessing extubation readiness; however, there are no universally accepted guidelines regarding their precise performance and reporting. Objective. To investigate variability in SBT practice across centres. Methods. Data from 680 patients undergoing 931 SBTs from eight North American centres from the Weaning and Variability Evaluation (WAVE) observational study were examined. SBT performance was analyzed with respect to ventilatory support, oxygen requirements, and sedation level using the Richmond Agitation Scale Score (RASS). The incidence of use of clinical extubation criteria and changes in physiologic parameters during an SBT were assessed. Results. The majority (80% and 78%) of SBTs used 5 cmH2O of ventilator support, although there was variability. A significant range in oxygenation was observed. RASS scores were variable, with RASS 0 ranging from 29% to 86% and 22% of SBTs performed in sedated patients (RASS < −2). Clinical extubation criteria were heterogeneous among centres. On average, there was no change in physiological variables during SBTs. Conclusion. The present study highlights variation in SBT performance and documentation across and within sites. With their impact on the accuracy of outcome prediction, these results support efforts to further clarify and standardize optimal SBT technique. PMID:27445575

  7. Practice Variation in Spontaneous Breathing Trial Performance and Reporting.

    PubMed

    Godard, Stephanie; Herry, Christophe; Westergaard, Paul; Scales, Nathan; Brown, Samuel M; Burns, Karen; Mehta, Sangeeta; Jacono, Frank J; Kubelik, Dalibor; Maziak, Donna E; Marshall, John; Martin, Claudio; Seely, Andrew J E

    2016-01-01

    Background. Spontaneous breathing trials (SBTs) are standard of care in assessing extubation readiness; however, there are no universally accepted guidelines regarding their precise performance and reporting. Objective. To investigate variability in SBT practice across centres. Methods. Data from 680 patients undergoing 931 SBTs from eight North American centres from the Weaning and Variability Evaluation (WAVE) observational study were examined. SBT performance was analyzed with respect to ventilatory support, oxygen requirements, and sedation level using the Richmond Agitation Scale Score (RASS). The incidence of use of clinical extubation criteria and changes in physiologic parameters during an SBT were assessed. Results. The majority (80% and 78%) of SBTs used 5 cmH2O of ventilator support, although there was variability. A significant range in oxygenation was observed. RASS scores were variable, with RASS 0 ranging from 29% to 86% and 22% of SBTs performed in sedated patients (RASS < -2). Clinical extubation criteria were heterogeneous among centres. On average, there was no change in physiological variables during SBTs. Conclusion. The present study highlights variation in SBT performance and documentation across and within sites. With their impact on the accuracy of outcome prediction, these results support efforts to further clarify and standardize optimal SBT technique.

  8. Developmental cardiorespiratory physiology of the air-breathing tropical gar, Atractosteus tropicus.

    PubMed

    Burggren, Warren W; Bautista, Gil Martinez; Coop, Susana Camarillo; Couturier, Gabriel Márquez; Delgadillo, Salomón Páramo; García, Rafael Martínez; González, Carlos Alfonso Alvarez

    2016-10-01

    The physiological transition to aerial breathing in larval air-breathing fishes is poorly understood. We investigated gill ventilation frequency (fG), heart rate (fH), and air breathing frequency (fAB) as a function of development, activity, hypoxia, and temperature in embryos/larvae from day (D) 2.5 to D30 posthatch of the tropical gar, Atractosteus tropicus, an obligate air breather. Gill ventilation at 28°C began at approximately D2, peaking at ∼75 beats/min on D5, before declining to ∼55 beats/min at D30. Heart beat began ∼36-48 h postfertilization and ∼1 day before hatching. fH peaked between D3 and D10 at ∼140 beats/min, remaining at this level through D30. Air breathing started very early at D2.5 to D3.5 at 1-2 breaths/h, increasing to ∼30 breaths/h at D15 and D30. Forced activity at all stages resulted in a rapid but brief increase in both fG and fH, (but not fAB), indicating that even in these early larval stages, reflex control existed over both ventilation and circulation prior to its increasing importance in older fishes. Acute progressive hypoxia increased fG in D2.5-D10 larvae, but decreased fG in older larvae (≥D15), possibly to prevent branchial O2 loss into surrounding water. Temperature sensitivity of fG and fH measured at 20°C, 25°C, 28°C and 38°C was largely independent of development, with a Q10 between 20°C and 38°C of ∼2.4 and ∼1.5 for fG and fH, respectively. The rapid onset of air breathing, coupled with both respiratory and cardiovascular reflexes as early as D2.5, indicates that larval A. tropicus develops "in the fast lane."

  9. 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

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

    NASA Astrophysics Data System (ADS)

    Cossette, Isabelle A.; Sabourin, Patrick

    2004-05-01

    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.

  11. 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.

  12. Effect of abdominal binders on breathing in tetraplegic patients.

    PubMed Central

    Goldman, J M; Rose, L S; Williams, S J; Silver, J R; Denison, D M

    1986-01-01

    We studied the effect on breathing of a conventional and a newly designed abdominal binder in seven patients with complete tetraplegia. The indices of respiratory ability used were the transdiaphragmatic pressure on maximal sniff (sniff Pdi), the maximum static inspiratory mouth pressure (PImax), and the vital capacity (VC). These were measured in patients with and without binders, in the supine position, raised up to 70 degrees on a tilt table, and seated upright. When patients were raised from the supine to the 70 degrees tilt and to the seated posture, sniff Pdi and VC decreased. Both binders improved VC in the seated position and at 70 degrees tilt, and sniff Pdi at 70 degrees tilt. The new binder was as effective as but no better than the conventional binder. PImax was too variable to be a valuable index of inspiratory power. These findings support the view that abdominal binders assist breathing in tetraplegic patients who are seated or raised to near vertical positions. Images PMID:2954256

  13. 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 ...

  14. 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 ...

  15. Exosomes and Cardiovascular Protection.

    PubMed

    Davidson, Sean M; Takov, Kaloyan; Yellon, Derek M

    2017-02-01

    Most, if not all, cells of the cardiovascular system secrete small, lipid bilayer vesicles called exosomes. Despite technical challenges in their purification and analysis, exosomes from various sources have been shown to be powerfully cardioprotective. Indeed, it is possible that much of the so-called "paracrine" benefit in cardiovascular function obtained by stem cell therapy can be replicated by the injection of exosomes produced by stem cells. However, exosomes purified from plasma appear to be just as capable of activating cardioprotective pathways. We discuss the potential roles of endogenous exosomes in the cardiovascular system, how this is perturbed in cardiovascular disease, and evaluate their potential as therapeutic agents to protect the heart.

  16. [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.

  17. 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

  18. 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

  19. Abnormal Breathing Patterns Predict Extubation Failure in Neurocritically Ill Patients

    PubMed Central

    Punj, Pragya; Nattanmai, Premkumar; George, Pravin

    2017-01-01

    In neurologically injured patients, predictors for extubation success are not well defined. Abnormal breathing patterns may result from the underlying neurological injury. We present three patients with abnormal breathing patterns highlighting failure of successful extubation as a result of these neurologically driven breathing patterns. Recognizing abnormal breathing patterns may be predictive of extubation failure and thus need to be considered as part of extubation readiness. PMID:28348899

  20. 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…

  1. 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.

  2. Elastohydrodynamic separation of pleural surfaces during breathing.

    PubMed

    Gouldstone, Andrew; Brown, Richard E; Butler, James P; Loring, Stephen H

    2003-08-14

    To examine effects of lung motion on the separation of pleural surfaces during breathing, we modeled the pleural space in two dimensions as a thin layer of fluid separating a stationary elastic solid and a sliding flat solid surface. The undeformed elastic solid contained a series of bumps, to represent tissue surface features, introducing unevenness in fluid layer thickness. We computed the extent of deformation of the solid as a function of sliding velocity, solid elastic modulus, and bump geometry (wavelength and amplitude). For physiological values of the parameters, significant deformation occurs (i.e. bumps are 'flattened') promoting less variation in fluid thickness and decreased fluid shear stress. In addition, deformation is persistent; bumps of sufficient wavelength, once deformed, require a recovery time longer than a typical breath-to-breath interval to return near their undeformed configuration. These results suggest that in the pleural space during normal breathing, separation of pleural surfaces is promoted by the reciprocating sliding of lung and chest wall.

  3. The Physics of Breath-Hold Diving.

    ERIC Educational Resources Information Center

    Aguilella, Vicente; Aguilella-Arzo, Marcelo

    1996-01-01

    Analyzes physical features of breath-hold diving. Considers the diver's descent and the initial surface dive and presents examples that show the diver's buoyancy equilibrium varying with depth, the driving force supplied by finning, and the effect of friction between the water and the diver. (Author/JRH)

  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. Quantification of periodic breathing in premature infants

    PubMed Central

    Mohr, Mary A.; Fairchild, Karen D.; Patel, Manisha; Sinkin, Robert A.; Clark, Matthew T.; Moorman, J. Randall; Lake, Douglas E.; Kattwinkel, John; Delos, John B.

    2015-01-01

    Background Periodic breathing (PB), regular cycles of short apneic pauses and breaths, is common in newborn infants. To characterize normal and potentially pathologic PB, we used our automated apnea detection system and developed a novel method for quantifying PB. We identified a preterm infant who died of SIDS and who, on review of her breathing pattern while in the NICU, had exaggerated PB. Methods We analyzed the chest impedance signal for short apneic pauses and developed a wavelet transform method to identify repetitive 10–40 second cycles of apnea/breathing. Clinical validation was performed to distinguish PB from apnea clusters and determine the wavelet coefficient cutoff having optimum diagnostic utility. We applied this method to analyze the chest impedance signals throughout the entire NICU stays of all 70 infants born at 32 weeks’ gestation admitted over a two-and-a-half year period. This group includes an infant who died of SIDS and her twin. Results For infants of 32 weeks’ gestation, the fraction of time spent in PB peaks 7–14 days after birth at 6.5%. During that time the infant that died of SIDS spent 40% of each day in PB and her twin spent 15% of each day in PB. Conclusions This wavelet transform method allows quantification of normal and potentially pathologic PB in NICU patients. PMID:26012526

  6. Fast and accurate exhaled breath ammonia measurement.

    PubMed

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

    2014-06-11

    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.

  7. 21 CFR 868.5260 - Breathing circuit bacterial filter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a device that is intended to remove... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing circuit bacterial filter....

  8. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 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...

  9. 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...

  10. 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...

  11. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 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...

  12. 46 CFR 197.340 - Breathing gas supply.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 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 197.450 - Breathing gas tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Breathing gas tests. 197.450 Section 197.450 Shipping....450 Breathing gas tests. The diving supervisor shall insure that— (a) The output of each air... or modification. (b) Purchased supplies of breathing mixtures supplied to a diver are checked...

  14. 14 CFR 29.1439 - Protective breathing equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Protective breathing equipment. 29.1439... Protective breathing equipment. (a) If one or more cargo or baggage compartments are to be accessible in flight, protective breathing equipment must be available for an appropriate crewmember. (b)...

  15. 21 CFR 868.2375 - Breathing frequency monitor.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing frequency monitor. 868.2375 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2375 Breathing frequency monitor. (a) Identification. A breathing (ventilatory) frequency monitor is a device intended to measure or monitor a...

  16. 42 CFR 84.122 - Breathing resistance test; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Breathing resistance test; minimum requirements. 84... Masks § 84.122 Breathing resistance test; minimum requirements. (a) Resistance to airflow will be measured in the facepiece or mouthpiece of a gas mask mounted on a breathing machine both before and...

  17. 46 CFR 108.703 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Self-contained breathing apparatus. 108.703 Section 108... 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...

  18. 46 CFR 108.635 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Self-contained breathing apparatus. 108.635 Section 108... 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...

  19. 46 CFR 108.703 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Self-contained breathing apparatus. 108.703 Section 108... 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...

  20. 21 CFR 868.5240 - Anesthesia breathing circuit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 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...

  1. 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...

  2. 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 airflow will be measured in the facepiece or mouthpiece while the apparatus is operated by a...

  3. 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…

  4. 21 CFR 868.5260 - Breathing circuit bacterial filter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing circuit bacterial filter. 868.5260... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a device that is intended to...

  5. 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...

  6. 42 CFR 84.122 - Breathing resistance test; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Breathing resistance test; minimum requirements. 84... Masks § 84.122 Breathing resistance test; minimum requirements. (a) Resistance to airflow will be measured in the facepiece or mouthpiece of a gas mask mounted on a breathing machine both before and...

  7. 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...

  8. 21 CFR 868.5240 - Anesthesia breathing circuit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 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...

  9. 46 CFR 108.635 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Self-contained breathing apparatus. 108.635 Section 108... 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...

  10. 46 CFR 169.736 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 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...

  11. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 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...

  12. 42 CFR 84.122 - Breathing resistance test; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Breathing resistance test; minimum requirements. 84... Masks § 84.122 Breathing resistance test; minimum requirements. (a) Resistance to airflow will be measured in the facepiece or mouthpiece of a gas mask mounted on a breathing machine both before and...

  13. 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...

  14. 21 CFR 868.2375 - Breathing frequency monitor.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breathing frequency monitor. 868.2375 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2375 Breathing frequency monitor. (a) Identification. A breathing (ventilatory) frequency monitor is a device intended to measure or monitor a...

  15. 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...

  16. 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...

  17. 21 CFR 868.5260 - Breathing circuit bacterial filter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breathing circuit bacterial filter. 868.5260... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a device that is intended to...

  18. 46 CFR 197.450 - Breathing gas tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Breathing gas tests. 197.450 Section 197.450 Shipping....450 Breathing gas tests. The diving supervisor shall insure that— (a) The output of each air... or modification. (b) Purchased supplies of breathing mixtures supplied to a diver are checked...

  19. 21 CFR 868.2375 - Breathing frequency monitor.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breathing frequency monitor. 868.2375 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2375 Breathing frequency monitor. (a) Identification. A breathing (ventilatory) frequency monitor is a device intended to measure or monitor a...

  20. 14 CFR 29.1439 - Protective breathing equipment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Protective breathing equipment. 29.1439... Protective breathing equipment. (a) If one or more cargo or baggage compartments are to be accessible in flight, protective breathing equipment must be available for an appropriate crewmember. (b)...

  1. 46 CFR 197.450 - Breathing gas tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Breathing gas tests. 197.450 Section 197.450 Shipping....450 Breathing gas tests. The diving supervisor shall insure that— (a) The output of each air... or modification. (b) Purchased supplies of breathing mixtures supplied to a diver are checked...

  2. 21 CFR 868.5260 - Breathing circuit bacterial filter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breathing circuit bacterial filter. 868.5260... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a device that is intended to...

  3. 21 CFR 868.2375 - Breathing frequency monitor.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing frequency monitor. 868.2375 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2375 Breathing frequency monitor. (a) Identification. A breathing (ventilatory) frequency monitor is a device intended to measure or monitor a...

  4. 46 CFR 197.450 - Breathing gas tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Breathing gas tests. 197.450 Section 197.450 Shipping....450 Breathing gas tests. The diving supervisor shall insure that— (a) The output of each air... or modification. (b) Purchased supplies of breathing mixtures supplied to a diver are checked...

  5. 21 CFR 868.5260 - Breathing circuit bacterial filter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing circuit bacterial filter. 868.5260... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5260 Breathing circuit bacterial filter. (a) Identification. A breathing circuit bacterial filter is a device that is intended to...

  6. 46 CFR 169.736 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 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...

  7. 21 CFR 868.2375 - Breathing frequency monitor.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing frequency monitor. 868.2375 Section 868...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2375 Breathing frequency monitor. (a) Identification. A breathing (ventilatory) frequency monitor is a device intended to measure or monitor a...

  8. 46 CFR 108.635 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Self-contained breathing apparatus. 108.635 Section 108... 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...

  9. 46 CFR 169.736 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 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...

  10. 21 CFR 868.5240 - Anesthesia breathing circuit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 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 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 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...

  12. 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...

  13. 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 airflow will be measured in the facepiece or mouthpiece while the apparatus is operated by a...

  14. 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 airflow will be measured in the facepiece or mouthpiece while the apparatus is operated by a...

  15. 46 CFR 197.450 - Breathing gas tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Breathing gas tests. 197.450 Section 197.450 Shipping....450 Breathing gas tests. The diving supervisor shall insure that— (a) The output of each air... or modification. (b) Purchased supplies of breathing mixtures supplied to a diver are checked...

  16. 46 CFR 108.703 - Self-contained breathing apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Self-contained breathing apparatus. 108.703 Section 108... 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...

  17. 14 CFR 29.1439 - Protective breathing equipment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Protective breathing equipment. 29.1439... Protective breathing equipment. (a) If one or more cargo or baggage compartments are to be accessible in flight, protective breathing equipment must be available for an appropriate crewmember. (b)...

  18. 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...

  19. Breathing Exercises for Inpatients with Sickle Cell Disease

    PubMed Central

    Matthie, Nadine; Brewer, Cheryl A.; Moura, Vera L.; Jenerette, Coretta M.

    2017-01-01

    Sickle cell disease (SCD) is a painful condition wherein breathing often is compromised. This pilot study supports the premise that individuals with SCD are willing to learn breathing exercises. Medical-surgical nurses should encourage breathing exercises for managing pain and preventing complications. PMID:26306354

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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... continuous rate of 85 liters per minute. (b) The exhalation resistance of demand apparatus shall not...

  9. 42 CFR 84.91 - Breathing resistance test; exhalation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation... continuous rate of 85 liters per minute. (b) The exhalation resistance of demand apparatus shall not...

  10. Hands-Off Approaches to Teaching Breath Support.

    ERIC Educational Resources Information Center

    Stufft, William David

    1998-01-01

    Addresses the importance of using a hands-off approach in today's world when teaching music students breath support techniques since any kind of touching might be seen as improper. Provides three different approaches in which students learn intercostal breathing methods. Considers the role of good posture in breath control. (CMK)

  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. 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...

  13. 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...

  14. 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...

  15. 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...

  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 84.195 - 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...

  18. 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...

  19. 21 CFR 868.5280 - Breathing tube support.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breathing tube support. 868.5280 Section 868.5280...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5280 Breathing tube support. (a) Identification. A breathing tube support is a device that is intended to support and anchor a patient's...

  20. 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:...

  1. 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:...

  2. 21 CFR 868.5280 - Breathing tube support.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing tube support. 868.5280 Section 868.5280...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5280 Breathing tube support. (a) Identification. A breathing tube support is a device that is intended to support and anchor a patient's...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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:...

  8. 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...

  9. 21 CFR 868.5280 - Breathing tube support.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing tube support. 868.5280 Section 868.5280...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5280 Breathing tube support. (a) Identification. A breathing tube support is a device that is intended to support and anchor a patient's...

  10. 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...

  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. 21 CFR 868.5280 - Breathing tube support.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing tube support. 868.5280 Section 868.5280...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5280 Breathing tube support. (a) Identification. A breathing tube support is a device that is intended to support and anchor a patient's...

  13. 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...

  14. 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...

  15. 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:...

  16. 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:...

  17. 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...

  18. 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...

  19. 21 CFR 868.5280 - Breathing tube support.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breathing tube support. 868.5280 Section 868.5280...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5280 Breathing tube support. (a) Identification. A breathing tube support is a device that is intended to support and anchor a patient's...

  20. 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...