Peripheral Opioid Receptor Antagonists for Postoperative Bowel Dysfunction

Abstract

POSTOPERATIVE ILEUS (POI) and opioid-induced bowel dysfunction (OBD) are two complications commonly experienced by surgical patients during the postoperative period. Both have been shown to delay surgical recovery, prolong hospitalization, and negatively affect quality of life. POI refers to a collection of signs and symptoms including bowel distention, lack of bowel sounds, nausea, anorexia, and delayed passage of flatus and stool; however, it should be noted that auniversal definition of POI does not exist. 1 Although all surgical patients may have these complications, patients undergoing abdominal surgery may be more at risk for POI than those undergoing other surgical procedures because of pathophysiologic changes that occur in the gastrointestinal (GI) tract as a result of surgical manipulation. Some factors that may contribute to the development of POI includealterations inelectricalperistaltic activity,upregulation of the sympathetic nervous system, and decreased muscle activity caused by inflammatory mediators. 1 OBD is characterized by constipation, abdominal pain, bloating, hard dry stool, and incomplete evacuation. These conditions occur as a result of delayed or inhibited gastric emptying, decreased propulsive activity, and increased fluid absorption in the GI tract. 2,3 Most patients will receive opioids for analgesia after surgery and, because OBD can exacerbate or hasten the development of POI, bowel function should be monitored closely in the days after surgery.