Abstract

Critically ill patients often have unique nutritional needs that require a rethinking of classic nutrition teaching. Semistarvation in the unstressed, malnourished patient is physiologically distinct from the response in the stressed, malnourished patient.

With starvation, net protein loss proceeds from most organs, skeletal muscle being the major contributor, whereas with stress, loss from skeletal muscle is increased, while certain organs, such as liver, and the wound experience net anabolism. Adequate feeding of the semi-starved, recuperating patient will result in effective lean tissue repletion, and overfeeding to a certain extent will increase the rate of repletion without adverse consequence. Meeting or modestly exceeding caloric balance while providing an ample (1.5 g/kg) protein intake will serve only to maintain the stressed patient, whereas substantial overfeeding can be harmful to organ function.

Standard formulations must often be modified in order to accommodate fluid restriction, organ failure, and limited central venous access.