Remimazolam vs. propofol for prevention of postoperative nausea and vomiting in laparoscopic gynecological surgery: a randomized non-inferiority trial.

backgroundPostoperative nausea and vomiting (PONV) is a prevalent complication, occurring in approximately 30% of surgical patients and reaching 80% in high-risk individuals. PONV is associated with prolonged recovery, increased healthcare costs, and reduced patient satisfaction. Although propofol can reduce the risk of PONV, it can cause adverse effects such as injection pain and hemodynamic instability. Remimazolam, a novel ultra-short-acting benzodiazepine, has a favorable safety profile, with more stable hemodynamics. While recent studies suggest that remimazolam may reduce PONV, the evidence comparing its antiemetic efficacy directly with propofol remains inconclusive, largely due to limited sample size. Therefore, this non-inferiority trail was conducted to determine whether remimazolam is non-inferior to propofol for the prevention of PONV.

methodsThis was a single-center, prospective, randomized, double-blind, non-inferiority trial. A total of 334 women aged 18-65 years, with American Society of Anesthesiologists (ASA) physical status I-III, undergoing elective laparoscopic gynecological surgery were enrolled. Patients were randomly assigned to receive either remimazolam or propofol for anesthesia induction and maintenance. The primary outcome was the incidence of PONV within 24 h. Secondary outcomes included the incidence of rescue antiemetic therapy, the types of PONV, the incidence of injection pain, the incidence of hypotension, the incidence of bradycardia, postoperative pain, and patient satisfaction.

resultsIn the per-protocol analysis (n = 326), the incidence of PONV was 58.3% (95/163) and 57.1% (93/163) in the remimazolam and propofol groups, respectively. The absolute difference was 1.2% (95% CI-9.5% to 12.0%), and the upper confidence limit exceeded the predefined non-inferiority margin of 5%. Remimazolam significantly reduced injection pain (9.6% vs. 54.5%; P < 0.001), hypotension within 10 min after induction (16.8% vs. 28.1%; P = 0.013), and intraoperative bradycardia (25.6% vs. 52.5%; P < 0.001). No significant differences were observed in the use of rescue antiemetics, PONV types, postoperative pain scores, or patient satisfaction.

conclusionAlthough non-inferiority of remimazolam to propofol for PONV prevention was not demonstrated in this high-risk population, remimazolam provided a superior safety profile, with significantly reduced injection pain and improved hemodynamic stability. These advantages position remimazolam as a valuable alternative for general anesthesia in settings where such adverse effects are of particular concern.

trial registrationChinese Clinical Trial Registry (ChiCTR2300076452,09/10/2023).