Nutritional Therapy in the Intensive Care Unit

Abstract

Meeting appropriate nutritional demands is a fundamental aspect of optimal patients’ care. Optimizing nutrition delivery and preventing malnutrition can have a significant positive effect on clinical outcomes and costs of the care. Providing nutrition in critically ill patients has long been challenging issue, due to the difficulties in determining the nutrition requirements of the patients with heterogeneous characteristics, and selecting the timing and the route of administration. Different guidelines have been created by the experts in order to help clinicians to choose the appropriate nutritional therapy. Unfortunately these guidelines and recommendations sometimes are changed over the time according to the knowledge from the latest studies. This review aims to provide a comprehensive synthesis and interpretation of the so far known literature for nutritional therapy in ICU in order to assist clinicians in making practical decisions regarding nutrition management during the different stages of critical illness. As a conclusion from the literature, indirect calorimetry is the preferred method for assessing resting energy expenditure and the appropriate caloric and protein intake to counter energy and muscle loss. Enteral nutrition (EN) is recommended as a preferred route for early nutrition therapy in critically ill patients over parenteral nutrition (PN). Both European and American guidelines recommend hypocaloric nutrition in the first 48 hours, at 70 – 80% of calculated caloric needs in order to avoid overnutrition. From day three, the European guidelines recommend a more aggressive approach in which nutritional support can be increased to as much as 100% of the patient’s requirements and supplemental parenteral nutrition can be provided if necessary.