Anoxic endurance of cardiac and respiratory function in the adult and infant rat

Abstract

In order to provide a quantitative measure of the relative susceptibility to anoxia of infant cardiac and respiratory function, as compared with those of the adult, newborn and adult rats were made to inhale pure nitrogen for varying periods. Care was taken to maintain the body temperature of the infants at a level comparable to that of the adults. The duration of respiratory efforts and of ventricular electrical activity was observed, and the data analyzed by appropriate statistical methods. On a scale of decreasing resistance to the effects of anoxia are to be found: infant rat ventricle; infant rat respiratory center; adult rat ventricle; adult rat respiratory center.