Enteral and parenteral feeding and monocyte gene expression in critically ill patients

During prolonged critical illness, most patients require life-sustaining nutritional support in the form of either enteral nutrition or parenteral nutrition. In providing much needed energy, nutritional support is indicated to counteract the effect of hypermetabolism on the stressed, critically ill patient. While intravenous nutrition was once believed to be a panacea, it is now known to have a significant and negative impact on critically ill patients. As the differential effects of enteral and parenteral nutrition are being investigated from both the clinical and basic science perspectives, it is apparent that specialized nutritional support has a profound impact on innate immunity and leukocyte gene expression. In particular, parenteral nutrition may be associated with an exaggerated immune response.