Enteral nutrition versus parenteral nutrition—the risks and benefits

Abstract

Nutritional support is an established and routine part of patient management. Conventionally, enteral nutrition is preferred to parenteral nutrition, because studies have indicated that enteral nutrition causes fewer complications. In this Review, the author critically analyzes the available data that compare these administration routes, and suggests that the effect of hyperglycemia, energy intake and obesity are perhaps more important than the route of nutrition in determining outcome. The role of nutrition in patient care became a part of mainstream medicine at about the end of the 1960s, with the publication of several papers that showed a benefit of nutritional support in the prevention of complications. At that time, the emphasis was on nutrition given by the parenteral route. Since then, a series of studies that compared parenteral nutrition with enteral nutrition have suggested that the enteral route of feeding causes fewer complications than the parenteral route. A careful review of the data shows that nutritional support can increase the risk of complications when given to well-nourished, obese and hyperglycemic patients. The avoidance of overfeeding and hyperglycemia is, therefore, of paramount importance. In this context, enteral nutrition, for which gastrointestinal tolerance limits overfeeding, can protect the patient.