The challenge of integrating a diagnosis of malnutrition in the practical application of nutrition care in the intensive care unit.

Evidence of poor nutrition status in a patient present on admission to the intensive care unit is associated with worse clinical outcomes than that for a well-nourished patient who becomes critically ill. Diagnosing malnutrition in this setting is fraught with difficulty, though, because elements of nutrition history are hard to obtain, the interpretation of anthropometric parameters is influenced by the disease process and interventions of critical care and the subjectivity of traditional assessment tools lacks precision. Determining the severity of disease drives the initial management and sets priorities in the derivation of the nutrition plan, focusing on strategies that promote survival. Its design should provide safe and effective nutrition support, avoiding aggressive feeding to make up for deficits in the acute phase of critical illness. In time, with resuscitation and stabilization, addressing pre-existing or developing malnutrition will change management and alter the design of the nutrition therapy.