Effect of esketamine on the ED50 of propofol for successful insertion of ureteroscope in elderly male patients: a randomized controlled trial.

Adding esketamine to propofol reduces the amount of propofol needed for successful ureteroscope insertion in elderly male patients compared with adding sufentanil. In a randomized trial of 49 elderly men undergoing rigid ureteroscopy, the median effective dose (ED50) of propofol was 1.356 mg/kg with esketamine versus 1.442 mg/kg with sufentanil, a statistically significant decrease. Induction time was also shorter with esketamine, and hemodynamic stability was better. Rates of adverse events such as hypoxemia and body movement did not differ between groups. The combination may improve safety by lowering propofol requirements in this older population.

Study at a glance

Abstract

Propofol is effective and used as a kind of routine anesthetics in procedure sedative anesthesia (PSA) for ureteroscopy. However, respiratory depression and unconscious physical activity always occur during propofol-based PSA, especially in elderly patients. Esketamine has sedative and analgesic effects but without risk of cardiorespiratory depression. The purpose of this study is to investigate whether esketamine can reduce the propofol median effective dose (ED50) for successful ureteroscope insertion in elderly male patients. 49 elderly male patients undergoing elective rigid ureteroscopy were randomly divided into two groups: SK Group (0.25 mg/kg esketamine+propofol) and SF Group (0.1 µg/kg sufentanil+propofol). Patients in both two groups received propofol with initial bolus dose of 1.5 mg/kg after sufentanil or esketamine was administered intravenously. The effective dose of propofol was assessed by a modified Dixon's up-and-down method and then was adjusted with 0.1 mg/kg according to the previous patient response. Patients' response to ureteroscope insertion was classified as "movement" or "no movement". The primary outcome was the ED50 of propofol for successful ureteroscope insertion with esketamine or sufentanil. The secondary outcomes were the induction time, adverse events such as hemodynamic changes, hypoxemia and body movement were also measured. 49 patients were enrolled and completed this study. The ED50 of propofol for successful ureteroscope insertion in SK Group was 1.356 ± 0.11 mg/kg, which was decreased compared with that in SF Group, 1.442 ± 0.08 mg/kg (P = 0.003). The induction time in SK Group was significantly shorter than in SF Group (P = 0.001). In SK Group, more stable hemodynamic variables were observed than in SF Group. The incidence of AEs between the two groups was not significantly different. The ED50 of propofol with esketamine administration for ureteroscope insertion in elderly male patients is 1.356 ± 0.11 mg/kg, significantly decreased in comparsion with sufentanil. Chinese Clinical Trial Registry, No: ChiCTR2300077170. Registered on 1 November 2023. Prospective registration. http://www.chictr.org.cn .