Nutritional support in the critically ill patient: if, when, how, and what

Nutritional support in the critically ill patient should be instituted as soon as it is clear that the patient will not eat within a week, whether the patient is at that particular time malnourished or not. The preceding discussion demonstrates that it is more a question of clinical judgment than of sophisticated nutritional assessment techniques, as most of these prove unreliable in the critically ill. However, muscle function testing seems to be promising in that regard, but more studies are required in the injured and septic patient. Enteral feeding is the favored route, although parenteral nutrition should be used without hesitation whenever the gastrointestinal tract is not functional. We recommend the use of 1.0 to 1.5 g/kg IBW/day of a balanced amino acid preparation. The use of BCAA-enriched solutions should await confirmation of the efficacy of these solutions in randomized prospective trials. Finally, it is our belief that critically ill patients should not receive more than 1.3 times their Harris-Benedict energy expenditure, and that this energy should be provided in the form of a glucose-fat mixture (50-50 system).