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A Model to Simulate Clinically Relevant Hypoxia in Humans
Published on: December 22, 2016
Hyperbaric nitrogen prolongs breath-holding time in humans
H Morooka1, Y Wakasugi, H Shimamoto
1Department of Anesthesiology, Nagasaki University School of Medicine, Japan. morooka@net.naasaki-u.ac.jp
Anesthesia and Analgesia
|August 29, 2000
Summary
Hyperbaric air significantly prolongs breath-holding time (BHT) more than hyperbaric oxygen. This effect is attributed to nitrogen
Area of Science:
- Physiology
- Hyperbaric Medicine
- Respiratory Physiology
Background:
- Changes in partial pressure of carbon dioxide (PaCO2) and oxygen (PaO2) influence respiratory stimulation.
- Breath-holding time (BHT) is a key indicator of respiratory system's response to gas changes.
Purpose of the Study:
- To compare the effects of hyperbaric air versus hyperbaric oxygen on BHT in humans.
- To investigate the influence of hyperbaric environments on respiratory control.
Main Methods:
- 36 healthy volunteers were exposed to 1.0 and 2.8 atmosphere absolute (ATA) in a hyperbaric chamber.
- Breath-holding time, pulse oximetry, and transcutaneous carbon dioxide tension were measured.
- Participants were divided into two groups: breathing air (Group A) or breathing oxygen (Group O).
Main Results:
- BHT was significantly prolonged in hyperbaric air (230 +/- 71 s at 2.8 ATA) compared to hyperbaric oxygen (180 +/- 52 s at 2.8 ATA).
- Transcutaneous carbon dioxide tension was higher in the hyperbaric air group (59 +/- 2 mm Hg) than in the hyperbaric oxygen group (54 +/- 2 mm Hg) at 2.8 ATA.
- The prolongation of BHT was significantly greater in hyperbaric air than in hyperbaric oxygen.
Conclusions:
- Hyperbaric air significantly prolongs BHT more than hyperbaric oxygen.
- The anesthetic effect of nitrogen in hyperbaric air may suppress the sensation of suffocation, leading to longer breath-holding durations.
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