The relationship between serum NSE, S-100 protein and nitric oxide levels and cognitive functions of patients following cardiovasculer surgery

SUMMARY Every year, many people undergo cardiovasculary surgery in the world. Due to improvement in coronary artery bypass surgery (CABG) tecnique, patients in high risk group such as patients with hypertension or diabetes mellitus are admitted to operation easily. But it should be remember that CABG in the high risk group of patient and also in the advanced age groups causes many neurological complications like stroke, postoperative delirium, depression, cognitive decline etc. Because of these problems, the effect of CABG on the brain functions gain more importence with respect to effects on postoperative heart status last years. In our study, 24 cases undergoing CABG and valve replacement (VR) were invastigated. Neuron-specific enolase (NSE) released from neurons, protein S-100B (S- 100B) released from glial cells and nitric oxide (NO) having many functions were studied in these casös to show cerebral effects of these operations. Also neuropsychological test using for assesment of cognitive functions were performed For this purpose, S-100B, NSE, NO levels were studied by collecting blood samples at 1., 6., 24. hours and 3., 7. days after surgery. In addition to this, neuropsychological tests were evaluated at pre- and postoperative time. After rjerforming of neuropsychological tests, cognitive decline was seen in 8 cases. S- 100B levels at postoperative 1. and 6. hours and also mean of age and perfussion time were significantly higher in these cases. NSE levels were significantiy higher in VR group at postoperative 7. days with respect to preoperative levels also. However there was no significant differance between preoperative and postoperative NO levels. In summary, cognitive decline is seen in CABG patients with advanced age and with long perfussion time frequently. And increased S~100B levels in these patients are correlated with cerebral influence which cause distrubtion of cognitive functions.