Appropriate use of parenteral nutrition through the perioperative period.

Recent advances in nutrition therapy of the patient undergoing elective surgery have focused on greater utilization of the gut, feeding closer to the time of surgery, avoiding extensive bowel preparations or use of nasogastric tubes and drains, and measures to promote and maintain intestinal motility. Failure to have protocols in place for delivery of enteral nutrition (EN) through the perioperative period should not lead to inappropriate use of parenteral nutrition (PN) as a default therapy, because in many circumstances, standard therapy with no specialized nutrition support may be associated with better outcome. In cases where EN is not feasible and the patient shows evidence of malnutrition, surgery should be delayed 7-10 days to provide perioperative PN. For patients requiring urgent surgery where EN is not feasible, the initiation of PN postoperatively should be delayed 5-7 days. Whether alternative sources for lipid emulsion and availability of parenteral immune-modulating agents in the future can improve the risk/benefit ratio of PN and expand its use through the perioperative period awaits further study.