The understanding of the importance of nutrition, particularly in the critically ill patient, is based on the known physiologic consequences of malnutrition. It includes respiratory muscle function, cardiac function, the coagulation cascade balance, electrolyte and hormonal balance, and renal function. Nutrition affects emotional and behavioral responses, functional recovery, and the overall cost of health care. The need to identify and treat the malnourished or potentially malnourished patient is a critical aspect of patient management. Much is known of catabolic and hypermetabolic state caused by trauma and burns. The response to injury needs to be mediated. There is much to learn about the intervention of that response through adjuvant nutritional therapy.