THE FACT that representatives of two specialties, obstetrics and pediatrics, are at this meeting indicates the interest of us all in every stage of the period that begins with an intrauterine fetus and ends with an extrauterine baby. Therefore, both the fetus and the newly born infant will be dealt with in this review of the fundamental principles of anoxia and cyanosis. In conclusion, an attempt will be made to describe briefly the beginning of extrauterine respiration.
Although anoxia is the subject of a vast literature, the facts have not changed since Means in 19241 clarified them by the diagrams presented, in somewhat modified form, in figure 1. It will be noted from the scheme of each diagram that in passage through the capillaries blood gives up a certain amount of its oxygen and simultaneously undergoes a decline in its oxygen tension. The amount of oxygen is expressed