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.

High dose of N-acetylcystein prevents acute kidney injury in chronic kidney disease patients undergoing myocardial revascularization.

BACKGROUND: The renoprotective effect of N-acetylcystein in patients undergoing coronary artery bypass graft surgery is controversial. METHODS: We assessed the renoprotective effect of the highest dose of N-acetylcystein sanctioned for clinical use in a prospective, double-blind, placebo-controlled study including 70 chronic kidney disease patients, stage 3 or 4, who underwent coronary artery bypass graft surgery, on cardiopulmonary bypass (CPB) and off CPB, and were randomly allocated to receive either N-acetylcystein 150 mg/kg followed by 50 mg/kg for 6 hours in 0.9% saline or only 0.9% saline. Acute kidney injury was defined by the Acute Kidney Injury Network classification. RESULTS: The incidence of kidney injury was reduced in the N-acetylcystein group (57.1% versus 28.6%, p=0.016). Nonuse of N-acetylcystein (relative risk 3.58, 95% confidence interval: 1.04 to 12.33, p=0.04) and cardiopulmonary bypass (relative risk 4.55, 95% confidence interval: 1.28 to 16.15, p=0.02) were independent predictors of kidney injury. In patients treated with CPB, N-acetylcystein reduced the incidence of kidney injury from 63% to 46%. Oxidative stress was increased in control subjects (p=0.01) and abolished in patients receiving N-acetylcystein. CONCLUSIONS: Maximum intravenous doses of N-acetylcystein reduce the incidence of acute kidney injury in patients with kidney disease undergoing coronary artery bypass graft surgery, abolish oxidative stress, and mitigate the negative effect of CPB on renal function.