Causes of bradycardia with static respiratory hypoxia in athletes

2021 ◽  
Vol 11 (1) ◽  
pp. 30-36
Author(s):  
Yu. E. Vaguine

According to some literature data, during voluntary long-term breath holding (BH), the heart rate (HR) increases, and according to others, it decreases.Objective: to determine the psychophysiological parameters that cause a change in HR during BH in athletes with different resistance to respiratory hypoxia.Materials and methods: HR at BH was studied in 14 beginner athletes, 15 basketball players and 12 swimmers-divers. Duration of BH was recorded. The HR was recorded on a heart rate monitor. After recording an electrocardiogram, the standard deviation of the duration of cardiac cycles was calculated. The arterial oxygen saturation was measured with a pulse oximeter. The statistically significant values of the correlation coefficient (r) were ≥0.33 with p < 0.05.Results: it was found that out of 41 sportsmen, HR increased by more than 5 % in 4, changed insignificantly in 7 and decreased by less than 5 % in 30. Beginner athletes had tachycardia, and BH was quickly interrupted by an imperative inhalation. The saturation of arterial blood with oxygen did not change and did not affect the change in HR. The decrease in heart rate in swimmers-divers in comparison with the other two groups of people examined was statistically significant (p < 0.05). The duration of BH had a direct correlation (r = 0.5) with bradycardia in these people. The duration of BH caused (r = 0.8) hypoxia, the value of which also directly influenced (r = 0.38) the severity of bradycardia. In addition, the decrease in HR depended on high HR (r = 0.36) and low HR variability (r = 0.38) before BH.Conclusion: tachycardia occurs in beginner athletes who experience discomfort with BH. Bradycardia occurs in sportsmen with a long-term BH setting without discomfort. Sympathicotonia in the prelaunch state predetermines the severity of bradycardia in BH. The duration of BH and the resulting hypoxia provide the occurrence of bradycardia.

PEDIATRICS ◽  
1995 ◽  
Vol 95 (6) ◽  
pp. 860-863 ◽  
Author(s):  
Christian F. Poets ◽  
Valerie A. Stebbens ◽  
David Richard ◽  
David P. Southall

Objective. To determine whether episodes of prolonged hypoxemia occur without prolonged apneic pauses (≥20 seconds) and without bradycardia (pulse rate, ≤100 beats per minute) in apparently well preterm infants. Methods. Long-term recordings of arterial oxygen saturation as measured by pulse oximetry (SpO2), photoplethysmographic (pulse) waveforms from the oximeter, and breathing movements were performed in 96 preterm infants (median gestational age at birth, 34 weeks; range, 28 to 36 weeks) who were breathing room air. Recordings started at a median age of 4 days (range, 1 to 60 days). Results. During a median duration of recording of 25 hours, 88 episodes in which SpO2 fell to 80% or less and remained there for 20 seconds or longer were identified in 15 infants. The median duration of these prolonged desaturations was 27 seconds (range, 20 to 81 seconds). In 73 episodes (83%), SpO2 continued to fall to 60% or less. Twenty-three desaturations were associated with prolonged apneic pauses and 54 with bradycardia; 19 of these were associated with both apnea and bradycardia. Thirty desaturations (34%; 10 infants) occurred without bradycardia and without prolonged apnea. Conclusions. These results indicate that a proportion of apparently well preterm infants exhibit episodes of severe prolonged hypoxemia unaccompanied by prolonged apneic pauses or bradycardia. Such episodes, therefore, would be difficult to detect if only breathing movements and heart rate are monitored. Indications for the use of oxygenation monitors in preterm infants should be reconsidered.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
R H Boeger ◽  
P Siques ◽  
J Brito ◽  
E Schwedhelm ◽  
E Pena ◽  
...  

Abstract Prolonged exposure to altitude-associated chronic hypoxia (CH) may cause high altitude pulmonary hypertension (HAPH). Chronic intermittent hypobaric hypoxia (CIH) occurs in individuals who commute between sea level and high altitude. CIH is associated with repetitive acute hypoxic acclimatization and conveys the long-term risk of HAPH. As nitric oxide (NO) is an important regulator of systemic and pulmonary vascular tone and asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of NO synthesis that increases in hypoxia, we aimed to investigate whether ADMA predicts the incidence of HAPH among Chilean frontiers personnel exposed to six months of CIH. We performed a prospective study of 123 healthy male subjects who were subjected to CIH (5 days at appr. 3,550 m, followed by 2 days at sea level) for six months. ADMA, SDMA, L-arginine, arterial oxygen saturation, systemic arterial blood pressure, and haematocrit were measured at baseline and at months 1, 4, and 6 at high altitude. Acclimatization to high altitude was determined using the Lake Louise Score and the presence of acute mountain sickness (AMS). Echocardiography was performed after six months of CIH in a subgroup of 43 individuals with either good (n=23) or poor (n=20) aclimatization to altitude, respectively. Logistic regression was used to assess the association of biomarkers with HAPH. 100 study participants aged 18.3±1.3 years with complete data sets were included in the final analysis. Arterial oxygen saturation decreased upon the first ascent to altitude and plateaued at about 90% during the further course of the study. Haematocrit increased to about 47% after one month and remained stable thereafter. ADMA continuously increased and SDMA decreased during the study course, whilst L-arginine levels showed no distinct pattern. The incidence of AMS and the Lake Louise Score were high after the first ascent (53 and 3.1±2.4, respectively) and at one month of CIH (47 and 3.0±2.6, respectively), but decreased to 20 and 1.4±2.0 at month 6, respectively (both p<0.001 for trend). In echocardiography, 18 participants (42%) showed a mean pulmonary arterial pressure (mPAP) greater than 25 mm Hg (mean ± SD, 30.4±3.9 mm Hg), out of which 9 (21%) were classified as HAPH (mPAP ≥30 mm Hg; mean ± SD, 33.9±2.2 mm Hg). Baseline ADMA, but not SDMA, was significantly associated with mPAP at month 6 in univariate logistic regression analysis (R = 0.413; p=0.007). In ROC analysis, a cut-off for baseline ADMA of 0.665 μmol/l was determined as the optimal cut-off level to predict HAPH (mPAP >30 mm Hg) with a sensitivity of 100% and a specificity of 63.6%. ADMA concentration increases during long-term CIH. It is an independent predictive biomarker for the incidence of HAPH. SDMA concentration decreases during CIH and shows no association with HAPH. Our data support a role of impaired NO-mediated pulmonary vasodilation in the pathogenesis of high altitude pulmonary hypertension. Acknowledgement/Funding CONICYT/FONDEF/FONIS Sa 09I20007; FIC Tarapaca BIP 30477541-0; BMBF grant 01DN17046 (DECIPHER); Georg & Jürgen Rickertsen Foundation, Hamburg


2000 ◽  
Vol 89 (3) ◽  
pp. 947-955 ◽  
Author(s):  
Giuseppe Insalaco ◽  
Salvatore Romano ◽  
Adriana Salvaggio ◽  
Alberto Braghiroli ◽  
Paola Lanfranchi ◽  
...  

The ventilatory and arterial blood pressure (ABP) responses to isocapnic hypoxia during wakefulness progressively increased in normal subjects staying 4 wk at 5,050 m (Insalaco G, Romano S, Salvaggio A, Braghiroli A, Lanfranchi P, Patruno V, Donner CF, and Bonsignore G; J Appl Physiol 80: 1724–1730, 1996). In the same subjects ( n = 5, age 28–34 yr) and expedition, nocturnal polysomnography with ABP and heart rate (HR) recordings were obtained during the 1st and 4th week to study the cardiovascular effects of phasic (i.e., periodic breathing-dependent) vs. tonic (i.e., acclimatization-dependent) hypoxia during sleep. Both ABP and HR fluctuated during non-rapid eye movement sleep periodic breathing. None of the subjects exhibited an ABP increase during the ventilatory phases that correlated with the lowest arterial oxygen saturation of the preceding pauses. Despite attenuation of hypoxemia, ABP and HR behaviors during sleep in the 4th wk were similar to those in the 1st wk. Because ABP during periodic breathing in the ventilatory phase increased similarly to the ABP response to progressive hypoxia during wakefulness, ABP variations during ventilatory phases may reflect ABP responsiveness to peripheral chemoreflex sensitivity rather than the absolute value of hypoxemia, suggesting a major tonic effect of hypoxia on cardiorespiratory control at high altitude.


Author(s):  
R. DeRossi ◽  
A.P. Benites ◽  
J.Z. Ferreira ◽  
J.M.N. Neto ◽  
L.C. Hermeto

In order to determine the analgesic and cardiovascular effects of the combination of epidural ketamine and lidocaine, 6 sedated cats were studied. Six healthy, young cats were used in a prospective randomised study. Each cat underwent 3 treatments, at least 1 week apart, via epidural injection: (1) ketamine (2.5 mg/kg), (2) lidocaine (4.0 mg/kg), and (3) ketamine (2.5 mg/kg) plus lidocaine (4.0 mg/kg). Epidural injections were administered through the lumbosacral space. Analgesia, motor block, sedation, heart rate, arterial blood pressure, respiratory rate and arterial oxygen saturation were measured. Rectal temperature was compared before and after sedation as well as after epidural administration of the drugs. Epidural administration of the ketamine/lidocaine combination induced prolonged analgesia extending from the coccygeal to the T13-L1 dermatomes, leading to severe ataxia. Cardiovascular effects were significant in all treatments: heart rate decreased, but there was a minimal reduction in arterial pressure. It was concluded that adding a dose of ketamine to epidural lidocaine in cats is feasible and effective.


1989 ◽  
Vol 17 (1) ◽  
pp. 44-48 ◽  
Author(s):  
S. R. Finfer ◽  
S. I. P. MacKenzie ◽  
J. M. Saddler ◽  
T. G. L. Watkins

The cardiovascular responses to tracheal intubation using a fibreoptic bronchoscope or Macintosh laryngoscope were compared in twenty in-patients and twenty day-stay patients. Within these groups patients were randomly allocated to direct laryngoscopic or fibreoptic bronchoscopic intubation. Arterial blood pressure, heart rate and arterial oxygen saturation were recorded before induction and at one-minute intervals until four minutes after intubation. In both groups both laryngoscopic and bronchoscopic intubation resulted in a significant rise in blood pressure and heart rate. At no stage was there a significant difference in mean blood pressure in either group, or in heart rate in the day-stay patients, between the different methods of intubation. In the in-patients mean heart rate was significantly higher in those patients intubated with the bronchoscope at three and four minutes after intubation. Time taken for intubation was significantly longer in those patients intubated with the bronchoscope. In no patient did the arterial oxygen saturation fall below 98%.


2018 ◽  
Vol 28 (1) ◽  
Author(s):  
Mahmood Ganjifard ◽  
Masoumeh Samii ◽  
Samaneh Kouzegaran ◽  
Amir Sabertanha

One of the major complications of general anesthesia in the recovery room is arterial oxygen desaturation and hypoxemia. Positive end-expiratory pressure (PEEP) can improve arterial oxygen saturation by increasing FRC. This study aims to evaluate the effects of applying PEEP on arterial oxygen saturation and hemodynamic parameters in the patient undergoing cesarean section in VALIASR hospital. In this double blind clinical trial we randomly allocated 120 patients of class1 and 2 ASA scheduled to undergoing cesarean section into 3 group (in 40).Different levels of PEEP (0, 5 and 10 CmH2o) were applied to each group while zero PEEP was established as control. All other variables (anesthesia and surgery techniques) were the same for all patients SPO2, noninvasive mean arterial pressure and heart rate were measured before, during and after surgery (Recovery room). The comparison of noninvasive arterial blood pressure and heart rate during and after surgery did not show significant differences but mean o2 saturation in group B (5 cmH2o PEEP) and C (10 cm H2o PEEP) in PACU was higher than control group (98.30±0.93 and 98.50±0.90 as opposed to97.12±1.15 respectively) P0<001. In light of results applying PEEP is effective in preventing desaturation after surgery and improving respiratory indexes without the significant hemodynamic changes, the result of using five cmH2o PEEP is more efficient and satisfying.


2020 ◽  
Vol 91 (10) ◽  
pp. 785-789
Author(s):  
Dongqing Wen ◽  
Lei Tu ◽  
Guiyou Wang ◽  
Zhao Gu ◽  
Weiru Shi ◽  
...  

INTRODUCTION: We compared the physiological responses, psychomotor performances, and hypoxia symptoms between 7000 m and 7500 m (23,000 and 24,600 ft) exposure to develop a safer hypoxia training protocol.METHODS: In altitude chamber, 66 male pilots were exposed to 7000 and 7500 m. Heart rate and arterial oxygen saturation were continuously monitored. Psychomotor performance was assessed using the computational task. The hypoxic symptoms were investigated by a questionnaire.RESULTS: The mean duration time of hypoxia was 323.0 56.5 s at 7000 m and 218.2 63.3 s at 7500 m. The 6-min hypoxia training was completed by 57.6% of the pilots and 6.1% of the pilots at 7000 m and at 7500 m, respectively. There were no significant differences in pilots heart rates and psychomotor performance between the two exposures. The Spo2 response at 7500 m was slightly severer than that at 7000 m. During the 7000 m exposure, pilots experienced almost the same symptoms and similar frequency order as those during the 7500 m exposure.CONCLUSIONS: There were concordant symptoms, psychomotor performance, and very similar physiological responses between 7000 m and 7500 m during hypoxia training. The results indicated that 7000-m hypoxia awareness training might be an alternative to 7500-m hypoxia training with lower DCS risk and longer experience time.Wen D, Tu L, Wang G, Gu Z, Shi W, Liu X. Psychophysiological responses of pilots in hypoxia training at 7000 and 7500 m. Aerosp Med Hum Perform. 2020; 91(10):785789.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shinshu Katayama ◽  
Jun Shima ◽  
Ken Tonai ◽  
Kansuke Koyama ◽  
Shin Nunomiya

AbstractRecently, maintaining a certain oxygen saturation measured by pulse oximetry (SpO2) range in mechanically ventilated patients was recommended; attaching the INTELLiVENT-ASV to ventilators might be beneficial. We evaluated the SpO2 measurement accuracy of a Nihon Kohden and a Masimo monitor compared to actual arterial oxygen saturation (SaO2). SpO2 was simultaneously measured by a Nihon Kohden and Masimo monitor in patients consecutively admitted to a general intensive care unit and mechanically ventilated. Bland–Altman plots were used to compare measured SpO2 with actual SaO2. One hundred mechanically ventilated patients and 1497 arterial blood gas results were reviewed. Mean SaO2 values, Nihon Kohden SpO2 measurements, and Masimo SpO2 measurements were 95.7%, 96.4%, and 96.9%, respectively. The Nihon Kohden SpO2 measurements were less biased than Masimo measurements; their precision was not significantly different. Nihon Kohden and Masimo SpO2 measurements were not significantly different in the “SaO2 < 94%” group (P = 0.083). In the “94% ≤ SaO2 < 98%” and “SaO2 ≥ 98%” groups, there were significant differences between the Nihon Kohden and Masimo SpO2 measurements (P < 0.0001; P = 0.006; respectively). Therefore, when using automatically controlling oxygenation with INTELLiVENT-ASV in mechanically ventilated patients, the Nihon Kohden SpO2 sensor is preferable.Trial registration UMIN000027671. Registered 7 June 2017.


Sign in / Sign up

Export Citation Format

Share Document