S100B protein and neuron-specific enolase as predictors of cognitive dysfunction after coronary artery bypass graft surgery: A prospective observational study.

BACKGROUND: Postoperative cognitive dysfunction (POCD) may be related to the systemic inflammatory response and an increase in serum markers of brain injury such as S100B protein and neuron-specific enolase (NSE). OBJECTIVE: The study aims to evaluate the association between POCD and serum levels of S100B and NSE after coronary artery bypass grafting surgery (CABG). DESIGN: Prospective observational study. SETTING: Single university teaching hospital. PATIENTS: We investigated 88 patients undergoing CABG. MAIN OUTCOMES MEASURES: Cognitive function was measured preoperatively, and at the 21st and 180th postoperative days (i.e. 6 months after surgery). S100B protein and NSE serum levels were evaluated preoperatively, after induction of anaesthesia, at the end of surgery and at 6 and 24 h after surgery. RESULTS: The incidence of POCD was 26.1% at 21 days after surgery and 22.7% at 6 months after surgery. Increased serum levels of S100B protein and NSE were observed postoperatively and may indicate brain damage. CONCLUSION: Although serum levels of S100B protein and NSE are both significantly increased postoperatively, our findings indicate that serum levels of S100B protein may be more accurate than NSE in the detection of POCD after CABG. TRIAL REGISTRATION: NCT01550159.