RESUMO
INTRODUCTION: Postoperative ileus (POI) is a common complication following major abdominal surgery. The majority of the data available regarding POI following abdominal surgery is from the gastrointestinal and urologic literature. These data have been extrapolated to vascular surgery, especially with regards to enhanced recovery programs for open abdominal aortic aneurysm (AAA) surgery. However, vascular patients are a unique patient population and extrapolation of gastrointestinal and urological data may not necessarily be appropriate. Therefore, the purpose of this study was to delineate the prevalence and risk factors of POI in patients undergoing open AAA surgery. METHODS: This was a retrospective, single-institution study of patients who underwent open AAA surgery from January 2016 to July 2023. Patients were excluded if they had undergone non-elective repairs or had expired within 72 hours of their index operation. The primary outcome was rates of POI, which was defined as the presence of two or more of the following after the third postoperative day: nausea and/or vomiting, inability to tolerate oral food intake, absence of flatus, abdominal distension, or radiological evidence of ileus. RESULTS: A total of 123 patients met study criteria with an overall POI rate of 8.9% (n=11). Patients who developed a POI had significantly lower BMIs (24.3 kg/m2 versus 27.1 kg/m2, P=.003), were more likely to undergo a transperitoneal approach (81.8% versus 42.0%, P=.022), midline laparotomy (81.8% versus 37.5%, P=.008), longer total clamp times (151.6 minutes versus 97.7 minutes, P=.018), larger amounts of intraoperative crystalloid infusion (3495 mL versus 2628 mL, P=.029), and were more likely to return to the operating room (27.3% versus 3.6%, P=.016). Proximal clamp site was not associated with POI (P=.463). POI patients also had higher rates of post-operative vasopressor use (100% versus 61.1%, P=.014) and larger amounts of oral morphine equivalents in the first 3 post-operative days (488.0 mg + 216.0 versus 203.8 mg + 29.6 P=.016). Patients who developed POI had longer lengths of stay (12.5 days versus 7.6 days, P<.001), longer duration of NGT decompression (5.9 days versus 2.2 days, P<.001), and a longer period of time before diet tolerance (9.1 days versus 3.7 days, P<.001). Of those that developed a POI (n=11), 4 (36.4%) required total parental nutrition during the admission. CONCLUSION: POI is a morbid complication amongst patients undergoing elective open AAA surgery that significantly prolongs hospital stay. Patients at risk for developing a POI are those with lower BMIs, had an operative repair via a transperitoneal approach, midline laparotomy, longer clamp times, larger amounts of intraoperative crystalloid infusion, a return to the operating room, post-operative vasopressor use, and higher amounts of oral morphine equivalents. These data highlight important peri-operative opportunities to reduce the prevalence of POI.