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Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department
Published on: January 30, 2011
[Effects of closed-circuit breathing apparatus on respiration and metabolism]
M Takahashi1, Y Mano, M Shibayama
1National Institute for Resources and Environment, Ibaraki, Japan.
Abstract:
The purpose of the study was to evaluate the influence of hyperoxia and hypercapnia on respiration and metabolism during a steady-state exercise. Thirteen healthy subjects were examined during bicycle-ergometer rides at approximately 50% VO2max under four different breathing gas conditions: 1) room air (control); 2) 40% oxygen; 3) 3% carbon dioxide; 4) 40% oxygen and 3% carbon dioxide. Hyperoxia, with or without hypercapnia, decreased respiratory ventilation and carbon dioxide elimination significantly. On the other hand, oxygen uptake in hyperoxia was not significantly different from that of normoxia. Hypercapnia increased respiratory ventilation more than 30% compared to normocapnia, but it did not change oxygen uptake and carbon dioxide elimination significantly.
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