Changes in plasma S-100.BETA. protein concentration in patients undergoing cardiac surgery performed with cardiopulmonary bypass

Abstract

Objective To evaluate the changes in plasma S-100β protein concentration in patients undergoing cardiac surgery performed with cardiopulmonary bypass (CPB).Methods ASA Ⅱ or Ⅲ patients aged 60-77 yr weighing 55-75 kg with national institutes of health stroke scale(NIHSS) ＜ 10 undergoing coronary artery bypass grafting with CPB were enrolled in this study.Cerebral function was evaluated and scored using NIHSS at 2 d after operation.The patients were divided into 3 groups according to NIHSS scores:group A uncomplicated (NIHSS score 0-9),group B mild brain injury (NIHSS score 10-19) and group C moderate and severe brain injury (NIHSS 20-45).Plasma S-100β protein concentration was measured before CPB,at 30 min of CPB,the end of CPB and 1 h,6 h,24 h after CPB.The duration of operation,CPB time,aortic cross-clamping time and length of ICU stay and hospital stay were recorded.Results Ten patients in groups A and B and 12 in group C completed the trial.Plasma S-100β protein concentration was significantly increased during and after CPB as compared with the baseline at T0 and peaked at T3 (groups A,B) and T4 (group C).The plasma S-100β protein concentration was highest in group C and lowest in group A.The duration of operation,CPB time,aortic cross-clamping time and length of ICU stay and hospital stay were longest in group C and shortest in group A.Conclusion Plasma S-100β protein concentration can be used as a marker of cerebral injury after cardiac surgery performed with CPB and the concentration measured at 6 h after CPB is more significant in evaluating the degree of cerebral injury and prognosis. Key words: S100 proteins; Cardiopulmonary bypass; Brain injurys; Cardiac surgical procedures