Voluntary breath-holding duration in healthy subjects with obesity: Role of peripheral chemosensitivity to carbon dioxide

Трембач, Н. В.; Zabolotskikh, I.B.

doi:10.1016/j.resp.2017.12.006

Cited by 8 publications

(8 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…• From these regression models we calculated both unadjusted and adjusted estimates of the association between the independent and dependent variables. Based on literature review [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] we controlled for and included the following variables in the adjusted models: age (≥50 vs. <50), sex (male vs. female), race (Black/African-American vs. all others), obesity (BMI ≥30 vs. <30), current smoking status (yes/no), history of asthma (yes/no), history of COPD (yes/no), history of congestive heart failure (yes/no), history of hypertension (yes/no), history of type 2 diabetes (yes/no), maximal breath hold time (seconds), baseline desaturation (<95% vs. ≥95%), and whether the subject was on nasal cannula oxygen at the time of conducting the study (yes/no). T-tests (continuous variables) and Fisher's exact tests (categorical variables) were used to compare the baseline characteristics of COVID-19 and healthy control subjects.…”

Section: Discussionmentioning

confidence: 99%

“…In the early months of the pandemic caused by the severe acute respiratory syndrome coronavirus 2 associated disease (COVID- 19), there were clinical reports of patients with COVID-19 who did not exhibit dyspnea [1], despite having hypoxemia and evidence of impaired pulmonary gas exchange [2]. This phenomenon was described as "happy" or "silent hypoxia.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Untitled

2024

COVID Res OA

View full text Add to dashboard Cite

Background: Some patients with severe acute respiratory syndrome coronavirus 2 associated disease presented with hypoxemia without exhibiting dyspnea. This phenomenon was called "silent" or "happy" hypoxia. The cause of "silent hypoxia" was unknown. It was suspected that COVID-19 might be altering structures vital to the normal respiratory drive. Oxygen sensing glomus cells of the carotid bodies, express the angiotensin-converting enzyme 2 receptors used by COVID-19 to infect cells. In a healthy person, hypoxemia stimulates carotid body neural activity triggering reflex stimulation of breathing and tachycardia. If COVID-19 infected the carotid bodies, the cells might not respond to hypoxemia. Methods:We performed a prospective observational pilot study where the ventilatory responses to breath holding tests in hospitalized patients with COVID-19 were compared to healthy controls in a single medical center. The aim was to determine whether ventilatory responses to hypoxia produced by breath holding in COVID-19 patients were different from those in volunteers without COVID-19. Results:In comparison to the control group, COVID-19 patients had significantly less post breath-holding respiration rate increase after maximal breath hold effort. COVID-19 patients also had significantly less post breath-holding desaturation after maximal breath hold effort in unadjusted analysis but not statistically significant in the adjusted model. This prospective observational study demonstrated that COVID-19 infection is associated with a statistically significantly smaller breathholding increase in respiratory rate. Conclusions:The findings indicate that COVID-19 may cause a blunted hypoxic ventilatory response in the infected patients during the early stages of pandemic.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Untitled

2024

COVID Res OA

View full text Add to dashboard Cite

show abstract

“…2). Studies on mechanism of cortical control of ventilation showed that the duration of breath-holding can be limited by several factors, such as sensitivity of peripheral chemoreflex, spirometry parameters, the arterial PCo 2 , PO 2, previous maneuver (Bain et al, 2017;Trembach & Zabolotskikh, 2018).Ventilatory response to PCo 2 and PO 2 is considerably variable between patient (West & Luks, 2016).The duration of voluntary breath-holding doubled after breathing a hyperoxic mixture or after pre-hyperventilation. Those whose minimum post breath-holding SaO 2 was lower, might have a higher likelihood of changing CPAP to BiPAP.…”

Section: Discussionmentioning

confidence: 99%

Useful variables during wake and sleep for prediction of positive airway pressure in obstructive sleep apnea titration

Setareh

Malekmohammad

Amini

et al. 2019

Sleep Science Practice

View full text Add to dashboard Cite

Background: Positive airway pressure is the main treatment modality in obstructive sleep apnea. The level of pressure needed for each patient is defined by a positive airway pressure titration study. Predicting those who need higher pressure or bi-level instead of continuous pressure is of a great clinical significance. This study was designed to evaluate whether voluntary breath-holding maneuver could predict Bilevel Positive Airway Pressure (BiPAP) or Continuous Positive Airway Pressure (CPAP) as the final optimal pressure in a split night study of patients with obstructive sleep apnea. Polysomnography (PSG) parameters specially oxygen saturation (SaO 2 ) during non-rapid eye movement (NREM), rapid eye movement sleep (REM), and duration of REM in diagnostic part may help determine the type of devices as soon as possible in split night study. Methods: The present research was conducted as a cross-sectional study of adults diagnosed as obstructive sleep apnea patients undergoing positive airway pressure (PAP) titration. Demographic, anthropometric, and polysomnographic data were collected. Patients were instructed to hold their breath as long as they could after five tidal breaths in the supine position. Baseline, post breath-holding phase, and recovery SaO 2 were recorded. These data were used to predict the pressure level and type of device. Results: Seventy-eight participants (56.4% male) with the mean age of 55.7 ± 13.9 years were included in the study. Mean and SD of apnea hypopnea index (AHI) and oxygen desaturation index (ODI) were 55.9 ± 34.4 and 38.3 ± 24 per hour, respectively. Most of the participants (65.3%) were categorized as CPAP group. CPAP and BiPAP groups were similar in terms of age, gender distribution, body mass index (BMI), neck circumference, and certain polysomnographic variables. Voluntary breath-holding maneuver showed a significant correlation between minimum SaO 2 and the need for changing to BiPAP during titration. Baseline and post breath-holding SaO 2 were not significantly lower in either group. NREM minimum SaO 2 and REM duration were the statistically significant correlated variables that predicted the need for BiPAP. Conclusion: Minimum oxygen following voluntary breath-holding maneuver along with higher BMI and larger neck circumference are predictors of the need to use BiPAP. Shorter REM duration and NREM minimum SaO 2 were other predictors of higher chance of BiPAP during titration of the present OSA participants.

show abstract

“…Such responses appear to be independent of the effects of obesity as well 19 . Central chemoreceptor activation elicited by hypercapnia is accentuated in those with obesity (although not all reports are consistent), whereas it is mainly the peripheral chemoreceptor response to hypoxemia that is enhanced in subjects with OSA 47,54,55 . Resting muscle sympathetic nerve activity, measured during normal awake normoxic breathing, is higher in subjects with OSA compared to obese controls 56,57 .…”

Section: Nrem Sleepmentioning

confidence: 97%

Apneic Sleep, Insufficient Sleep, and Hypertension

2019

View full text Add to dashboard Cite

These changes progressively increase from lighter to deeper stages of NREM, i.e. sleep stages N1 through N3. BP, HR, cardiac output and peripheral vascular resistance all decrease in NREM stages 1 through 3 10,11 . Thus, BP normally shows a "dipping" pattern at night 12 . REM sleepIn rapid eye movement (REM) sleep, there is a reduction in tone of the respiratory muscles except for the diaphragm 13 . Simultaneously, a decrease in sensitivity of the central chemoreceptors occurs 14 . Consequently, ventilation decreases to levels even lower than that seen during NREM sleep and PaCO2 levels start to rise. Sympathetic tone increases during tonic REM sleep, with intermittent surges in both sympathetic and parasympathetic activation during phasic REM, with marked BP and HR fluctuations, such that the overall BP and HR in REM sleep are similar to the levels seen during wakefulness 10 . WakefulnessAn "arousal" from sleep is represented by a change in the electroencephalogram for <10 seconds, and if this change is prolonged for 10 or more seconds, it is termed as an "awakening" 15 . During arousals and awakenings from sleep, sudden increases in minute ventilation, HR and BP are noted 16,17 . Some degree of ventilatory "overshoot" occurs in that the increase in respiratory drive during arousals and awakenings is higher than that expected for the PaCO2 level at the time 16 . A rise in sympathetic activity and decline in parasympathetic tone occurs; the consequent rise in BP and HR during arousals and awakenings significantly exceeds baseline wakefulness levels 17 . SLEEP-RELATED BREATHING DISORDERS AND HYPERTENSIONOSA is the most common sleep-related breathing disorder, characterized by repeated complete (apnea) or partial (hypopnea) upper airway inspiratory closure in sleep 18 . The severity of OSA is gauged by the number of disordered breathing events per hour of sleep or recording time on a sleep study (in-laboratory polysomnography or a home sleep apnea test). The events are accompanied by oxyhemoglobin desaturation and sometimes with arousals from sleep. Up to 24% of men and 9% of women between 30-60 years of age are estimated to have OSA in the general U.S. adult population, with some other cohorts showing higher prevalence rates of sleep disordered breathing (SDB) (e.g. 50% of men and 23% of women with moderate to severe SDB in a population-based study in Switzerland) 1, 2 . Mechanisms linking sleep apnea and hypertensionThe chemoreflexes-Whereas in normal sleep, changes in BP are mainly sleep stage dependent, in subjects with SDB, these changes depend on the severity of disordered breathing events 19,20 . Recurrent episodes of cessation of breathing due to upper airway closure or narrowing with accompanying hypoxemia lead to chemoreflex-mediated sympathetic activation 21 . At the termination of the disordered breathing event, an increase in cardiac output occurs, but this is delivered into a constricted vasculature. As a result, intermittent rises in BP as high as 250/110 mm Hg may be noted in individuals with OSA, t...

show abstract

Voluntary breath-holding duration in healthy subjects with obesity: Role of peripheral chemosensitivity to carbon dioxide

Abstract: The sensitivity of peripheral chemoreflex to CO was preserved in healthy men with obesity. The higher sensitivity of peripheral chemoreflex to CO and higher WHR were associated with a decrease in the duration of voluntary apnea in subjects with obesity.

Cited by 8 publications

References 28 publications

Untitled

Untitled

Useful variables during wake and sleep for prediction of positive airway pressure in obstructive sleep apnea titration

Apneic Sleep, Insufficient Sleep, and Hypertension

Contact Info

Product

Resources

About