Parenteral nutrition in the critically-ill patient: more harm than good?

While many studies have reported that providing parenteral nutrition (PN) c an change nutritional outcomes, there are limited data that demonstrate tha t PN influences clinically-important end points in critically-ill patients. The purpose of the present paper is to systematically review and criticall y appraise the literature to examine the relationship between PN and morbid ity and mortality in the critically-ill patient. Studies comparing enteral nutrition (EN) with PN and studies comparing PN with no PN were reviewed. T he results suggest that EN is associated with reduced infectious complicati ons in some critically-ill subgroups. PN, on the other hand, is associated with increased morbidity and mortality in critically-ill patients. When nut ritional support is indicated, EN should be used preferentially over PN. Fu rther studies are needed to define the optimal timing and composition of PN in patients not tolerating sufficient EN. Strategies to optimize EN delive ry and minimize PN utilization in critically-ill patients are indicated.