Both the Trendelenburg position and pneumoperitoneum with carbon dioxide have been reported to increase intracranial pressure (ICP) and to alter cerebral blood flow or cerebral blood volume. Also anesthetic agents have variable effects on cerebral hemodynamics and ICP. The present study was conducted to determine whether regional cerebral oxygen saturation (rSO₂) values differ between propofol and sevoflurane anesthesia during laparoscopic surgery in the Trendelenburg position.

Thirty-two adult women undergoing gynecological laparoscopic surgery were divided into sevoflurane and propofol groups. rSO₂ values were recorded at 10 min after induction in the neutral position (Tpre), 10 min after the pneumoperitoneum in the Trendelenburg position (Tpt) and 10 min after desufflation in the neutral position (Tpost). For analysis of rSO₂, we did ANOVA and univariate two-way ANCOVA with covariates being mean arterial pressure and end tidal carbon dioxide tension.

Between sevoflurane and propofol groups, the change in rSO₂ was significantly different even after ANCOVA. rSO₂ at Tpt (76.3 ± 5.9% in sevoflurane vs 69.4 ± 5.8% in propofol) and Tpost (69.5 ± 7.1% in sevoflurane vs 63.8 ± 6.6% in propofol) were significantly higher in the sevoflurane group compared with the propofol group. In the propofol group, rSO₂ at Tpost was significantly lower than at Tpre (71.1 ± 4.8%) and cerebral oxygen desaturation occurred in two patients (14.3%).

Significantly lower rSO₂ values were observed in the propofol group during gynecological laparoscopic surgery. The possibility of cerebral oxygen desaturation should not be overlooked during propofol anesthesia even after desufflation of the abdomen in the neutral position.