Effects of Remimazolam, Propofol, and Sevoflurane on Cerebral Oxygenation During Gynecologic Laparoscopic Surgery: A Prospective Randomized Study

Background and aim: Laparoscopic gynecologic surgery frequently requires Trendelenburg positioning and carbon dioxide insufflation, both of which may alter cerebral oxygen dynamics. While the effects of propofol and sevoflurane on regional cerebral oxygen saturation have been investigated previously, limited information is available regarding remimazolam. This study aimed to compare changes in rSO₂ among patients receiving remimazolam, sevoflurane, or propofol anesthesia during gynecologic laparoscopic surgery in the Trendelenburg position. The primary endpoint was the change in rSO₂ measured at predefined perioperative time points among the three anesthetic groups. Methods: A total of 72 women with American Society of Anesthesiologists (ASA) physical status I-II who were scheduled for elective gynecologic laparoscopic surgery were included in this prospective randomized study. Participants were allocated equally to maintenance anesthesia with remimazolam (R group), propofol (P group), or sevoflurane (S group). Regional cerebral oxygen saturation was continuously assessed using near-infrared spectroscopy. Regional cerebral oxygen saturation (rSO₂) values were recorded before anesthetic induction, 5 min after induction, 5 min following Trendelenburg positioning, and 5 min after restoration of the neutral position. Temporal changes in rSO₂ and between-group differences were analyzed using repeated-measures ANOVA. Results: Baseline demographic and perioperative characteristics were comparable among groups. Regional cerebral oxygen saturation increased after induction and remained preserved throughout surgery in all groups. Repeated-measures ANOVA demonstrated a significant effect of time on rSO₂ (F {3, 207} = 32.89, p < 0.001) and a significant group-by-time interaction (F {6, 207} = 3.58, p = 0.002), whereas the overall group effect was not significant (F {2, 69} = 1.71, p = 0.189). Although the sevoflurane group showed numerically higher rSO₂ values, no significant overall difference in cerebral oxygenation was observed among groups. Bispectral index (BIS) values were significantly higher in the remimazolam group than in the propofol and sevoflurane groups (F {2, 69} = 45.81, p < 0.001). Mean arterial pressure after return to the neutral position was significantly higher in the remimazolam group than in the propofol and sevoflurane groups (p = 0.003). Cerebral oxygen desaturation occurred in one patient in the propofol group and in no patients in the remimazolam or sevoflurane groups. Conclusions: Remimazolam, propofol, and sevoflurane all maintained adequate cerebral oxygenation during gynecologic laparoscopic surgery performed in the Trendelenburg position. Although sevoflurane demonstrated numerically higher rSO₂ values, no significant overall difference in cerebral oxygenation was identified among anesthetic techniques. Remimazolam provided cerebral oxygenation comparable to that of propofol and sevoflurane while offering superior hemodynamic stability, suggesting that it may be a useful alternative anesthetic agent for procedures requiring Trendelenburg positioning.