Gautier H, Milic-Emili J, Miserocchi G, Siafakas N M
Respir Physiol. 1980 Jun;40(3):365-77. doi: 10.1016/0034-5687(80)90035-3.
Pattern of breathing and mouth occlusion pressure have been investigated during a 6-day sojourn at an altitude of 3457 m in six resting subjects breathing ambient air or an hyperoxic mixture. It has been shown that ventilation increases and alveolar PCO2 decreases, both variables reaching a steady-state after about 4 days at altitude. Changes in ventilation are caused by modifications, at first, in the timing component of the respiratory cycle and later on, in the mean inspiratory airflow. This suggests that the output of the respiratory center is qualitatively modified during the acclimatization period. Mouth occlusion pressure, an index of neuromuscular inspiratory drive, increased on the first day at altitude, remaining constant thereafter. The mean inspiratory flow did not change on the first day, but progressively increased in the subsequent 3 days. The observation that flow increased in the face of a constant neuromuscular inspiratory drive suggests that during acclimatization to altitudes, the progressive increase in ventilation is due to changes in mechanics of the ventilatory pump rather than changes in central neural drive.
对6名静息状态的受试者在海拔3457米处停留6天期间呼吸环境空气或高氧混合气时的呼吸模式和口腔闭合压进行了研究。结果表明，通气增加，肺泡PCO2降低，这两个变量在海拔约4天后达到稳态。通气变化首先是由呼吸周期的时间成分改变引起的，随后是平均吸气气流改变。这表明在适应期呼吸中枢的输出在质量上发生了改变。口腔闭合压是神经肌肉吸气驱动力的指标，在海拔第一天升高，此后保持不变。平均吸气流量在第一天没有变化，但在随后3天逐渐增加。在神经肌肉吸气驱动力恒定的情况下流量增加这一观察结果表明，在适应海拔过程中，通气的逐渐增加是由于通气泵力学变化而非中枢神经驱动变化所致。
