591: Evaluation of Aprepitant Use in Bariatric Surgery to Prevent Postoperative Nausea and Vomiting

Introduction: With over 40 million patients undergoing surgery annually in the United States, at least one-third experience postoperative nausea and vomiting (PONV). PONV is one of the most common adverse events associated with general anesthesia in all types of surgeries, including bariatric surgery. Due to multiple risk factors associated with increased risk of PONV, antiemetic prophylaxis has been recommended and shown benefits in reducing the risk. Aprepitant, a neurokinin 1 (NK1) receptor antagonist, has been proven to be one of the superior agents utilized. Studies have shown aprepitant to be more effective than more commonly seen agents, such as ondansetron and palonosetron, for preventing vomiting 24 hours after surgery and in reducing nausea severity in the first 48 hours after surgery. In addition, due to its mechanism of action, aprepitant can be useful for PONV due to opioids since they cause upregulation of NK-1 receptors. Methods: We performed a retrospective chart review of patients receiving aprepitant prior to bariatric surgery from June 2024 to October 2024 and patients not receiving aprepitant from January 2024 to May 2024 (before aprepitant added to formulary). PONV was defined as having at least one emesis episode and/or a patient complaint of nausea after completion of bariatric surgery. Results: We reviewed 150 patient charts, 90 in aprepitant group and 60 in non-aprepitant group. The primary outcome is no nausea/emesis 48 hours post bariatric surgery. The secondary outcomes are number of emesis episodes; time to first emesis episode, and time to first antiemetic use. Sixty-six of the 90 aprepitant patients (73%) experienced no nausea/vomiting comparing to 20 patients (67%) in non-aprepitant group within 48 hours. Average PONV episodes per patient is 1.6 for aprepitant group and 1.7 for non-aprepitant group. Of those who had PONV, the median time to first emesis is 19 hours in aprepitant group vs. 18 hours in non-aprepitant group. Conclusions: In our study, aprepitant showed minimal efficacy in preventing PONV in bariatric surgery patients comparing to standard antiemetic regimen.