Abstract:Objective To evaluate the effects of different anesthesia depths on postoperative cognitive function in patients undergoing supratentorial tumor resection.Methods One hundred patients undergoing supratentorial tumor resection were selected and divided into group L and group D, with 50 patients in each group. The electroencephalographic bispectral index (BIS) was kept between 45 and 60 in group L and between 30 and 45 in group D. Mean arterial pressure (MAP) and heart rate (HR) were recorded before induction (T0), before endotracheal tube placement (T1), and at the time of skin incision (T2), suture (T3), and recovery of orientation (T4). Cognitive function was assessed with the Mini-Mental State Examination (MMSE) scale.Results MAP and HR of groups L and D at T1-T3 were significantly lower than that at T0 (P<0.05); no significant differences in MAP and HR were observed between the two groups at any time point (P>0.05). Group D had significantly higher MMSE scores than group L at 1 and 3 days after operation (P<0.05), but no significant difference was observed at 7 days after operation (P>0.05).Conclusions During surgical resection of supratentorial tumors, BIS between 30 and 45 have less influence on the early postoperative cognitive function of patients.