Protective effects of remifentanil preconditioning on cerebral injury during pump-assisted coronary artery bypass graft

The protective effects of remifentanil preconditioning on serum superoxide dismutase (SOD) and malondialdehyde (MDA) during pump-assisted coronary artery bypass graft (CABG) were investigated. Forty pump-assisted CABG patients were randomly divided into a remifentanil preconditioning group (R group) and a control group (C group, N = 10; normal saline). The R group was further divided into 3 sub-groups (R1, R2, and R3; N = 10 per group) according to the remifentanil dose (0.6, 1.2, and 1.8 μg·kg -1 ·min -1 , respectively). A venous blood sample was taken at anesthesia induction (T 0 ), before cardiopulmonary bypass (CPB) (T 1 ), CPB 30 min (T 2 ), and after CPB (T 3 ), and protein concentrations were measured. Patients were tested 24 h before and after the operation with the Mini-Mental State Examination (MMSE), and the difference was calculated. The MMSE score difference in the R3 group was lower than those of the other 3 groups (P < 0.05). At T 2 and T 3 , the R3 group showed a significant decrease in S-100β protein and MDA and an increase in SOD (P < 0.05) compared with the other groups, and S-100β was negatively correlated with SOD activity (T 2 : r = -0.76, -0.80, P < 0.01; T 3 : r = -0.795, P <