Controversies and Misconceptions in Intensive Care Unit Nutrition.

The early initiation of enteral nutrition remains a fundamental component of the management of critically ill and injured patients in the intensive care unit. Trophic feeding is equivalent, if not superior, to full-dose feeding. Parenteral nutrition has no proved benefit over enteral nutrition, which is the preferred route of nutritional support in intensive care unit patients with a functional gastrointestinal tract. Continuous enteral and parental nutrition inhibits the release of important enterohormones. These changes are reversed with intermittent bolus feeding. Whey protein, which is high in leucine, has a greater effect on insulin release and protein synthesis than does a soy- or casein-based enteral formula.