抄録
The mechanics of breathing were studied before and during acute hypoxia induced by a low oxygen inhalation in nine normal subjects, five males and four females. Three subjects inhaled 14.5% oxygen and six subjects inhaled 10% oxygen.During the hypoxia both functional and static compliance were decreased. However, the decrease of the functional compliance was greater than the decrease of the static compliance. Therefore, differences between the functional and static compliance increased during the low oxygen inhalation.There was a slight increase in inspiratory and expiratory mechanical resistance, especially in the expiratory resistance during the hypoxia.There was some correlation between the percent of reduction of the pulmonary compliance and the increase of the mean pulmonary artery pressures and to the decrease of the arterial oxygen saturation, but no correlation was found between the increased mechanical resistance and the arterial oxygen saturation.On the basis of these results, it seems likely that the decrease of the pulmonary compliance during the acute induced hypoxia will be caused by the increased tone of the pulmonary artery system attributable to increased pulmonary artery pressures. On the other hand the increase of mechanical resistance seems to be caused by the bronchoconstriction. Other causal factors of these changes were discussed.
