LAUSR

Background Remimazolam besylate is a newer benzodiazepine with characteristics of quick onset of effects, short maintenance and recovery times without accumulation in tissues. This trial was conducted to confirm the efficacy and safety of remimazolam besylate versus propofol during hysteroscopy. Methods Patients undergoing hysteroscopy were randomly assigned to either the remimazolam (Group R) or the propofol group (Group P). Group R was administered an induction dose of 0.2 mg/kg and a maintenance dosage of 1.0 mg/kg/h. In Group P, propofol was started at 1.5–2.0 mg/kg and then maintained at 3.0–6.0 mg/kg/h. After remimazolam besylate or propofol induction, remifentanil was infused using a target-controlled infusion system with a target concentration of 1.5 ng/ml and titrated during the procedure. The incidence rates of injection pain, low oxygen saturation (SpO 2 ) and adverse effects in both groups were compared. Results Eighty-two patients were included in this study. The incidence of adverse events in Group R (3.7%) was significantly lower than that in Group P (36.6%) ( p  < 0.001). The incidence of injection pain in Group P (80.5%) was much higher than that in Group R (2.4%) ( p  < 0.001). The incidence of other adverse events, such as low SpO 2 , bradycardia, and hypotension in Group R was lower than that in Group P ( p  < 0.05). Conclusions Remimazolam besylate proves to be a safer alternative for anesthesia during hysteroscopy. Moreover, adverse events caused by propofol, such as low SpO 2 and injection pain, are largely avoided. Trial registration This study was approved by the Clinical Research Ethics Committee of Mengcheng County No. 1 People’s Hospital (2020MYL20003) and registered at http://www.chictr.org.cn (15/09/2020, ChiCTR-2000038252 ). The study protocol followed the CONSORT guidelines. The study protocol was performed in the relevant guidelines.