Combined Use of Etomidate and Propofol Reduce the Duration of Apnea vs Propofol Alone in Patients Undergoing Hysteroscopy: A Randomised Double-Blind Trial.

BACKGROUND: The incidence of respiratory suppression remains high in outpatients receiving intravenous anesthesia for hysteroscopy, presenting a substantial risk to safety. Combined use of etomidate and propofol may reduce apnea duration compared with propofol alone. OBJECTIVE: To verify the co-primary hypotheses that the Etomidate-propofol combination provides non-inferior sedation efficacy and superior reduction of apnea duration compared with propofol alone. METHODS: The double-blind, parallel-group randomized trial was conducted at Renji Hospital, Shanghai, from September 2022 to December 2023. Women aged 18-65 years for elective hysteroscopies under intravenous sedation were included. The exclusion criteria included upper airway abnormalities, severe preoperative cardiac, liver, or kidney diseases, preoperative respiratory insufficiency, high reflux risk, allergy to study drugs, or serious psychological disorders or used psychotropic medications. Patients were randomized to receive either 0.2% etomidate 10mg + 1% propofol 100 mg or 1% propofol 150 mg alone, both in a total volume of 15 mL. All patients were given sufentanil (0.15 µg/kg). Co-primary outcomes were non-inferiority in sedation efficacy with an 7% margin and superiority on apnea duration. RESULTS: A total of 365 subjects were included with combination (n = 182) and propofol alone (n = 183). Patients in both groups were adequately sedated, and the combination was significantly non-inferior to propofol alone. Median apnea duration was significantly shorter in the combined group (73 s) than in the propofol group (116 s, difference, -43 s; P < 0.001). Fewer patients in the combined group required manual ventilation (17% vs 37% for propofol, P < 0.0001). Haemodynamic responses were similar for each approach. CONCLUSION: The combination of etomidate and propofol provides comparable sedative efficacy to propofol alone during hysteroscopy, while significantly shortening apnea duration induced by intravenous sedatives.