IT IS well known that dextrose may be given in large amounts and be retained by the normal organism. However, how much of this ingested dextrose the body is capable of oxidizing in time of need and how much is merely assimilated as glycogen is problematic. This question has received much attention with respect to normal and diabetic persons. Yet few studies have been conducted on the surgical patient, who is confronted by an urgent need for calories in the postoperative period in order to combat starvation ketosis and to prevent depletion of body proteins. In this paper an attempt is made to determine whether the preoperative and postoperative periods are associated with normal oxidation of carbohydrates. Inasmuch as carbohydrates have been used until now as the principal food to meet the caloric requirement in the postoperative state, the question of oxidation of carbohydrate during this time is obviously