Nutrition support of critically ill patients. Guidelines for optimal management

Nutrition support is an important component of the management of critically ill patients. Before support is initiated, realistic goals should be established and risks and benefits considered. Initially, hemodynamic status should take precedence over nutritional status. Enteral feeding is the preferred route when the gastrointestinal tract is functioning. In most cases calorie requirements can be estimated adequately with use of the Harris-Benedict equation. Indirect calorimetry provides valuable information in patients with impending respiratory failure; withdrawing excess calories and substituting lipid calories for carbohydrate calories, if necessary, may be beneficial. Clinical response can be assessed by nitrogen balance studies and weekly measurement of weight and serum transferrin levels.