Parenteral nutrition in surgical patients.

Nitrogen balance has been studied under conditions of simple fasting and in the postoperative period on a total of 102 patients. It is much more difficult to restore a positive nitrogen balance in the post-traumatic period, and this can be obtained only with calorie and, above all, amino acid quotas much higher than those capable of equilibrating the balance of fasting patients. The absence of a constant relationship between nitrogen sparing and the caloric value of the solutions infused and the advantages of hyperamino-acid therapy for the purpose of the balance agree with the hypothesis that the postoperative protein catabolism has the purpose of supplying the injured area with intermediate carbohydrate metabolites and constitutes the theoretic basis for the use of parenteral hyperalimentation during the postoperative period. This can be planned with doses of 35 to 40 calories per kilogram per day in the form of dextrose solution plus at least 2 grams of amino acids per kilogram per day.