Key result
Acute isocapnic hypoxia persistently reset the baroreflex to higher pressures, shifting the DBP error signal from -3.9 mmHg at baseline to 0.2 mmHg posthypoxia (P<0.05).
Why the study?
Does acute isocapnic hypoxia alter baroreflex control of muscle sympathetic nerve activity in humans?
Population
14 humans (mean age 26 ± 1 yr; 3 women)
Comparison
Exposure to 20 min of isocapnic hypoxia vs Baseline (normoxia)
Follow-up
5 min following termination of hypoxia
Authors
Loading...
No immediate practice change for hypoxic patients; leaves open baroreflex role in sustained sympathetic activity.
Does acute isocapnic hypoxia alter baroreflex control of muscle sympathetic nerve activity in humans?
Absolute Event Rate: -1.4% vs -3.9%
p-value: p=<0.05
Acute isocapnic hypoxia causes a persistent resetting of the baroreflex to higher levels of muscle sympathetic nerve activity that outlasts the hypoxic stimulus.
Querido et al. (2011) studied Acute hypoxia (n=14). Acute isocapnic hypoxia vs. Baseline was evaluated on Diastolic blood pressure (DBP) error signal (p=<0.05). Acute isocapnic hypoxia persistently reset the baroreflex to higher pressures, shifting the DBP error signal from -3.9 mmHg at baseline to 0.2 mmHg posthypoxia (P<0.05).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: