Opioid-free versus opioid-based anesthesia for postoperative nausea and vomiting in laparoscopic cholecystectomy: A Systematic Review with Meta-Analysis, Meta-Regression and Trial Sequential Analysis

Background: Postoperative nausea and vomiting (PONV) are frequent complications following laparoscopic cholecystectomy. Opioid-free anesthesia has emerged as a potential alternative to opioid-based anesthesia to reduce its occurrence. In this context, we performed a systematic review to compare the incidence of PONV between these two anesthesia alternatives, as well as to evaluate postoperative pain control and intraoperative hemodynamic stability. Methods: This systematic review was conducted in accordance with PRISMA guidelines (CRD420251068278). Searches were performed in PubMed, Embase, Scopus, and the Cochrane Library, and included only randomized controlled trials. The quality of evidence was assessed using the GRADE system. Results: Ten trials, including 1065 patients, were analyzed. Opioid-free anesthesia was associated with a significant reduction in PONV (RR = 0.30; 95% CI 0.18–0.48; p < 0.001). Postoperative pain, by the Numeric Rating Scale, was lower in the opioid-free group at 2 h (MD = −0.72; 95% CI −1.05 to −0.39; p < 0.001) and 8 h (MD = −0.83; 95% CI −1.20 to −0.46; p < 0.001), whereas no differences were detected at 24 h (MD = −0.16; 95% CI −0.40 to 0.07; p = 0.177). The incidence of intraoperative hypotension was significantly reduced in the opioid-free group. No differences were observed for bradycardia, need for rescue analgesia, or opioid consumption within 24 h. Conclusions: The available pooled evidence in the literature indicates, with moderate certainty, that opioid-free anesthesia reduces PONV without compromising postoperative analgesia or intraoperative hemodynamic stability in patients undergoing laparoscopic cholecystectomy.