Glycopyrronium Bromide versus Droperidol for Prophylaxis of Postoperative Nausea and Vomiting in Hysteroscopic Day Surgery: A Randomized, Double-Blind, Non-Inferiority Trial.

PURPOSE: To investigate the efficacy of glycopyrronium bromide in preventing postoperative nausea and vomiting (PONV) in patients undergoing gynecological hysteroscopic day surgery. PATIENTS AND METHODS: This study is a prospective, randomized, double-blind, non-inferiority trial. The non-inferiority margin was set at 15%. Patients scheduled for elective gynecological hysteroscopic day surgery under general anesthesia from November 2025 to February 2026 were selected. A total of 260 eligible patients were randomly assigned to receive glycopyrronium bromide (Group G) or droperidol (Group F). Patients in Group G received intravenous glycopyrronium bromide 0.2 mg, while those in Group F received intravenous droperidol 1 mg. Surgery was performed under general anesthesia with remimazolam combined with alfentanil. The primary outcome observed was the incidence of PONV within 24 hours after surgery in both groups. RESULTS: Within 24 hours postoperatively, the incidence of nausea and vomiting in Group G was non-inferior to that in Group F (37.1% vs 34.1%, risk difference 3.0%; 95% confidence interval -9.0 to 14.7; upper limit < non-inferiority margin of 15%). In the PACU, the incidence of nausea and vomiting in Group G and Group F was 22.6% vs 17.9%, respectively (risk difference 4.7%; 95% confidence interval -5.4 to 14.6). Regarding perioperative adverse reactions, there was no statistically significant difference in the incidence of hypotension between the two groups(30.6% vs 39.8%, P=0.130). The incidence of bradycardia was higher in Group F than in Group G (7.3% vs 1.6%, P=0.030). Furthermore, the incidence of parched mouth was higher in Group G than in Group F (67.7% vs 15.4%, P=0.001). CONCLUSION: This study found that glycopyrronium bromide is non-inferior to droperidol in preventing PONV within 24 hours after gynecological hysteroscopic day surgery.