Effects of clopidogrel on perioperative blood loss in off pump elective coronary artery bypass surgery. A prospective single blinded observational study

Background Concern about possible hemorrhagic complications arising from use of oral antiplatelet agents in immediate proximity to CABG surgery leads many physicians to avoid or discontinue these agents preoperatively exposing these patients to risk of perioperative myocardial infarction, stroke and vascular event. So we aimed to study the effect of clopidogrel on perioperative blood loss in patients who stopped the drug before surgery with variable time periods. The study was designed to evaluate the effect of preoperative clopidogrel on Coronary Artery Bypass Grafting (CABG) surgery outcome in terms of perioperative blood loss. Methods Data were collected prospectively on eighty consequective patients who underwent elective CABG at our institute between Dec. 2007 and May 2008. All surgeries were performed by single team of cardiac surgeons and anaesthesiologist and done off pump. The preoperative data collected include age, gender, body mass index, diabetes, chronic renal failure, prothrombin time, international normalized ratio, activated partial thromboplastin time, platelet count and European System for Cardiac Operative Risk Evaluation (EURO score). Intraoperative data collected include number of grafts, duration of surgery, amount of heparin and protamine used and amount of blood loss. Postoperative data include the amount collected in the chest tubes. Patients were divided into 3 groups- group1- clopidogrel stopped within 0–4 days of operation, group 2-clopidogrel stopped within 5–8 days before operation and group 3-clopidogrel discontinued more than 8 days before operation. Results The mean total blood loss was 967.3±252.1 ml. In group 1 the mean total blood loss was 850.3±279.2 ml, group 2 the mean total blood loss was 1021.4±220.2 ml and in group 3 the mean total blood loss was 958.13±262.10 ml. Conclusions There is no statistically significant difference in blood loss between three groups. In our study we could not find any significant association between perioperative blood loss and clopidogrel.