Indirect calorimetry: relevance to patient outcome.

Indirect calorimetry provides an important adjunctive monitor for the provision of nutrition support in the critically ill patient. Accuracy in determining caloric requirements may serve to optimize benefit from nutrition therapy and improve patient outcome. A number of strategies in nutrition management in the intensive care setting (eg, dosing of enteral nutrition, monitoring cumulative caloric balance, and deliberate but "permissive" underfeeding) necessitate the determination of a fairly specific goal for caloric provision. Inaccuracy leading to inappropriate under- or overfeeding may generate additional morbidity and adverse clinical consequences for patients already at high risk from hypermetabolic stress response to injury.