Nutritional support of the elderly patient in an intensive care unit.

Critically ill elderly patients are at high risk to develop protein-energy malnutrition as well as micronutrient deficiencies. They have characteristic metabolic alterations which must be understood in order to provide nutritional support. Current nutritional status can be assessed by clinical and laboratory parameters. The enteral and parenteral routes of administering nutrition and their advantages, disadvantages, complications, and monitoring are discussed.