Effects of Chronic Hypercapnia on Electrolyte and Acid-Base Equilibrium. I. Adaptation*

Although chronic respiratory acidosis is one of the commonest clinical disturbances of acid-base balance, the process of adaptation which it induces has not been extensively investigated. Normal man tolerates prolonged exposure to high CO., tensions poorly and is, therefore, not a suitable subject for study. Recent observations in the rat exposed to a high CO, atmosphere (1, 2) have provided much valuable information, but no balance data are available in the dog, the animal which appears more closely to resemble man in its adjustment to other disturbances of acid-base equilibrium. For this reason, and in order to provide a basis for further investigations of chronic hypercapnia in the dog, the present stud- ies of adaptation were undertaken.