The importance of nutrition in critically ill patients.

Metabolic and physiologic changes during critical illness can be protective mechanisms for hospitalized patients but increases their risk for malnutrition. Clinicians must assess patients' nutritional status during acute illness and determine their need for nutritional support. By understanding the physiologic changes and patients' metabolic adaptations to stress, clinicians can choose the appropriate assessment tool and type of nutritional support needed to improve outcomes in critically ill patients.