Huang S Y, Alexander J K, Grover R F, Maher J T, McCullough R E, McCullough R G, Moore L G, Sampson J B, Weil J V, Reeves J T
J Appl Physiol Respir Environ Exerc Physiol. 1984 Mar;56(3):602-6. doi: 10.1152/jappl.1984.56.3.602.
Hypoxia at high altitude stimulates ventilation, but inhibitory influences in the first days after arrival limit the ventilatory response. Possible inhibitory influences include hypocapnia and depression of ventilation during sustained hypoxia. Our approach was to compare hypoxic ventilatory responses at low altitude with ventilation at high altitude. In 12 subjects we compared responses both to isocapnic hypoxia and poikilocapnic (no CO2 added) hypoxia during acute (less than 10 min) and sustained (30 min) hypoxia in Denver (1,600 m) with ventilations measured on each of 5 days on Pikes Peak (4,300 m). On Pikes Peak, day 1 ventilation [minute ventilation = 10.0 1/min, BTPS; arterial O2 saturation (Sao2) = 82%] was less than predicted by either acute isocapnic or poikilocapnic tests. However, sustained poikilocapnic hypoxia (Sao2 approximately = 82%) in Denver yielded ventilation similar to that on Pikes Peak on day 1. By Pikes Peak days 4 and 5, endtidal PCO2, pHa, and Sao2 approached plateaus, and ventilation (12.4 1/min, BTPS) on these days was as predicted by the acute isocapnic test. Thus the combination of hypocapnia and sustained hypoxia may have blunted the ventilatory increase on Pikes Peak day 1 but apparently not after 4 or 5 days of acclimatization.
高海拔地区的低氧会刺激通气，但到达后的头几天内的抑制性影响会限制通气反应。可能的抑制性影响包括低碳酸血症和持续性低氧期间通气的抑制。我们的方法是将低海拔地区的低氧通气反应与高海拔地区的通气情况进行比较。在12名受试者中，我们比较了丹佛（1600米）急性（少于10分钟）和持续性（30分钟）低氧期间对等碳酸性低氧和变碳酸性（不添加二氧化碳）低氧的反应，以及在派克斯峰（4300米）5天中的每一天所测得的通气情况。在派克斯峰，第1天的通气量[分钟通气量 = 10.0升/分钟，体温、气压、饱和水蒸气压状态；动脉血氧饱和度（Sao2） = 82%]低于急性等碳酸性或变碳酸性测试的预测值。然而，丹佛的持续性变碳酸性低氧（Sao2约为82%）产生的通气量与派克斯峰第1天的相似。到派克斯峰第4天和第5天，呼气末二氧化碳分压、动脉血pH值和Sao2接近平稳状态，这几天的通气量（12.4升/分钟，体温、气压、饱和水蒸气压状态）如急性等碳酸性测试所预测的那样。因此，低碳酸血症和持续性低氧的共同作用可能在派克斯峰第1天抑制了通气量的增加，但在适应4或5天后显然没有这种情况。
