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The human ventilatory response to stimulation by transient hypoxia
The Journal of Physiology
|June 1, 1981
Summary
Healthy subjects exposed to brief hypoxia showed varied breathing pattern changes. Inspiratory time increased with tidal volume, suggesting a dynamic respiratory control system response.
Area of Science:
- Respiratory Physiology
- Human Physiology
- Breathing Control
Background:
- Breathing patterns adapt to physiological challenges.
- Hypoxia is a significant stimulus affecting respiratory regulation.
Purpose of the Study:
- To detail transient breathing pattern changes after a hypoxic stimulus.
- To investigate the interplay between tidal volume, frequency, and breath timing.
Main Methods:
- Healthy subjects underwent a brief hypoxic stimulus (nitrogen breaths).
- Ventilation, tidal volume, and breath timing were recorded breath-by-breath.
- Data were time-averaged to analyze response patterns.
Main Results:
- All subjects increased ventilation, with variable contributions from tidal volume and frequency.
- Inspiratory time increased with tidal volume in most subjects.
- Decreased expiratory time contributed to reduced total breath duration.
Conclusions:
- The initial increase in inspiratory time may precede increased respiratory drive.
- This suggests a dynamic feature in the respiratory control system's response to stimuli.
- Breathing pattern adjustments to hypoxia are complex and individualized.
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