SIGNIFICANCE OF SERUM S100 RELEASE AFTER CORONARY-ARTERY BYPASS-GRAFTING

Background. S100 protein has been suggested to be a serum marker for c erebral complications after cardiac operation and extracorporeal circu lation. The aim of this study was to characterize the S100 release pat tern after extracorporeal circulation in 515 consecutive patients unde rgoing coronary artery bypass grafting. Methods. Clinical variables an d outcome were prospectively registered. The cerebral outcome was dete rmined by clinical examination. S100 was measured at the end of extrac orporeal circulation, and after 5, 15, and 48 hours. Results. After op eration, 13 patients had stroke, 12 had delayed awakening, and 17 had encephalopathy. Early S100 release, immediately after extracorporeal c irculation, was associated with age and perfusion time, but not with c erebral outcome. However, S100 release after 5 to 48 hours was associa ted with cerebral complications and risk factors for such outcome. Pat ients with stroke had higher S100 levels after 15 to 48 hours. A subse t of patients with renal failure had overall higher S100 levels at 5 h ours. Conclusions. Early and late S100 release indicate different mech anisms for release and emphasizes the potential power of this new bioc hemical marker for cerebral damage. (C) 1998 by The Society of Thoraci c Surgeons.