Effect of intravenous N-acetylcysteine on outcomes after coronary artery bypass surgery: a randomized, double-blind, placebo-controlled clinical trial.
OBJECTIVE
N-acetylcysteine, a potent anti-inflammatory and antioxidant agent, is known to decrease the production of reactive oxygen species after cardiac surgery. The objective of this study was to evaluate the effects of intravenous N-acetylcysteine on clinical and biochemical outcomes after coronary artery bypass surgery with cardiopulmonary bypass.


METHODS
One hundred patients (mean age 60.5 years, range 43-78 years, 89% male) undergoing coronary artery bypass grafting at the Montreal Heart Institute were randomized to receive either N-acetylcysteine (600 mg orally the day before and the morning of the operation, a bolus of 150 mg/kg of intravenous N-acetylcysteine before skin incision, followed by perfusion at 12.5 mg x kg(-1) x h(-1) over 24 hours; n = 50) or placebo (n = 50). The patients and clinical team were blinded to group assignments. Preoperative characteristics were similar between the two groups. Postoperative clinical data (death, myocardial infarction, low-output syndromes, arrhythmias, bleeding, transfusion requirements, and intensive care unit and hospital lengths of stay) and biochemical markers (creatine kinase MB, troponin T, creatinine, hemoglobin, and platelet levels) were evaluated serially over 4 days.


RESULTS
Clinical outcomes were not significantly different between the two groups with regard to the incidence of death, myocardial infarction, bleeding, transfusion requirements, intubation time, and hospital length of stay. No differences were found in postoperative biochemical markers (troponin T, creatine kinase MB, creatinine, hemoglobin, and platelets) between the groups. No differences were observed between the groups in interleukin-6 production (P = not significant).


CONCLUSIONS
Prophylactic use of N-acetylcysteine in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass does not lead to improvement in clinical results or biochemical markers. Further strategies to decrease reperfusion injury should be devised.
El-Hamamsy
Ismail
I
Research Center and Department of Surgery, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada.
Stevens
Louis-Mathieu
LM
Carrier
Michel
M
Pellerin
Michel
M
Bouchard
Denis
D
Demers
Philippe
P
Cartier
Raymond
R
Page
Pierre
P
Perrault
Louis P
LP
D000111:Acetylcysteine / Q000008:administration & dosage*; D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D000975:Antioxidants / Q000008:administration & dosage*; D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D011183:Postoperative Complications; D011300:Preoperative Care
D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D015850:Interleukin-6; D000111:Acetylcysteine