Improving intensive care unit outcome with total parenteral nutrition: Lessons from a case study

SummaryCritical illness poses several unique nutritional challenges. Critically ill patients are frequently hypermetabolic and are susceptible to protein catabolism and losses (eg, via traumatic or surgical wounds). The provision of optimal calories and nutritional substrates to avert catabolism is often hindered by limitations in enteral feeding, delays in initiating nutrition, and a lack of reliable means by which to accurately measure energy expenditure and, hence, caloric requirements in this patient population. Evidence suggests that failure to meet the nutritional needs of intensive care unit patients may prove detrimental, with adverse effects on morbidity and mortality. In this article, a case study of a critically injured patient provides a focus around which key aspects of intensive care unit nutritional support are reviewed, including optimal timing and caloric and macronutrient requirements. The role of parenteral nutrition in meeting the nutritional needs of intensive care unit patients is highlighted, as is the value of rigorous monitoring of energy expenditure in achieving this goal.