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 (T0), before cardiopulmonary bypass (CPB) (T1), CPB 30 min (T2), and after CPB (T3), 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 T2 and T3, 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 (T2: r = -0.76, -0.80, P < 0.01; T3: r = -0.795, P < 0.01), and was positively correlated with MDA density (T2: r = 0.71, P < 0.01; T3: r = 0.71, P < 0.01). In conclusion, high-dosage remifentanil preconditioning played a protective role on brain damage, possibly through inhibition of the oxidative stress response.