Effects of isolated-impaired fasting glucose on brain injury following cardiac surgery under cardiopulmonary bypass

Abstract

Objective To observe the effect of isolated-impaired fasting glucose (IIFG) on brain injury in patients undergoing cardiac surgery under cardiopulmonary bypass (CPB). Methods Rheumatic heart valve disease patients with normal fasting blood glucose (control group; n=25) and with IIFG (IIFG group; n=25), who underwent elective mitral valve replacement, were randomly selected in this study. Preoperative, peroperative, and postoperative neuron specific enolase (NSE), S100B and myelin basic prote (MBP) levels were compared. Results NSE and S100B levels were higher in IIFG group than in control group when the termination of CPB, 2 h after termination of CPB, and 24 h after surgery [NSE: (9.12±0.94), (13.87±2.55), (12.67±3.38) μg/L vs. (7.21±0.81), (9.11±1.20), (7.47±1.22) μg/L; t=4.125, 4.567, 3.689; P=0.000, 0.000, 0.000; S100B: (2.09±0.33), (4.21±0.79), (2.36±0.54) μg/L vs. (1.23±0.25), (2.39±0.48), (1.22±0.24) μg/L; t=3.497, 4.077, 3.576; P=0.001, 0.000, 0.000]. The expression of MBP was not statistically significant between the two groups. Delirium occurred in two cases of IIFG group and one case of control group. Signs and symptoms of other brain injuries were not detected in both groups. Conclusion Compared with the patients with normal fasting blood glucose, NSE and S100B levels were relatively higher in patients with IIFG after surgery under CPB. Key words: Cardiopulmonary bypass; Cardiac surgery; Fasting glucose; Brain injury