Robertson H T, Hlastala M P
J Appl Physiol Respir Environ Exerc Physiol. 1977 Aug;43(2):357-64. doi: 10.1152/jappl.1977.43.2.357.
A negative aADCO2 has been demonstrated during ventilation with hypercarbic gas mixtures and during rebreathing, but has never been demonstrated during normal gas exchange. This anomalous behavior of CO2 was studied by comparing it to the behavior of five infused inert gases during normal gas exchange in 10 anesthetized mongrel dogs. The distribution of VA/Q heterogeneity and the respiratory dead space in the animals was quantitated using excretion-solubility data from the five infused inert gases. The predicted excretion fraction (PACO2/PVCO2) for CO2 was obtained from the inert gas excretion-solubility curve, using a measured solubility for CO2. The measured excretion fraction for CO2 (PACO2/PVCO2), even after correction for Haldane effect, was significantly greater than the predicted fraction (P less than 0.001). This corresponded to an alveolar PCO2 that exceeded the predicted value by a mean of 5.0 Torr.
在使用高碳酸气体混合物通气期间以及重复呼吸期间已证实存在负的肺泡-动脉二氧化碳分压差（aADCO2），但在正常气体交换期间从未证实过。通过将其与10只麻醉杂种犬正常气体交换期间5种注入的惰性气体的行为进行比较，研究了二氧化碳的这种异常行为。利用5种注入惰性气体的排泄-溶解度数据对动物的通气/血流比值（VA/Q）异质性分布和呼吸死腔进行了定量分析。使用测得的二氧化碳溶解度，从惰性气体排泄-溶解度曲线获得二氧化碳的预测排泄分数（PACO2/PVCO2）。即使校正了哈代效应后，测得的二氧化碳排泄分数（PACO2/PVCO2）仍显著高于预测分数（P<0.001）。这相当于肺泡二氧化碳分压平均超过预测值5.0托。
