Enteral and parenteral nutrition: evidence-based approach.

Nutrition support for patients in hospital has become an essential form of therapy. Total parenteral nutrition (TPN) was the preferred way of giving nutrition to hospital patients for many years but enteral nutrition (EN) is now the preferred route. EN is believed to promote gut function and prevent translocation of intestinal bacteria, thus reducing the incidence of sepsis in critically ill patients. In consequence, the use of TPN has been discouraged as a dangerous form of therapy. Critical review of the data suggests that in the human subject TPN does not cause mucosal atrophy or increase translocation of bacteria through the small intestine. However, overfeeding, which is easy with TPN, can explain the results of studies which have shown that TPN increases sepsis. Furthermore, the risks of TPN-induced complications have been exaggerated. When there is risk of malnutrition and EN is not tolerated, or there is gut failure, TPN is an equally effective and safe alternative.