Clinical Trial of the Neuroprotectant Clomethiazole in Coronary Artery Bypass Graft Surgery

Abstract

Background The neuroprotective property of clomethiazole has been demonstrated in several animal models of global and focal brain ischemia. In this study the authors investigated the effect of clomethiazole on cerebral outcome in patients undergoing coronary artery bypass surgery. Methods Two hundred forty-five patients scheduled for coronary artery bypass surgery were recruited at two centers and prospectively randomized to clomethiazole edisilate (0.8%), 225 ml (1.8 mg) loading dose followed by a maintenance dose of 100 ml/h (0.8 mg/h) during surgery, or 0.9% NaCl (placebo) in a double-blind trial. Coronary artery grafting was completed during moderate hypothermic (28-32 degrees C) cardiopulmonary bypass. Plasma clomethiazole was measured at several intervals during and up to 24 h after the end of infusion. A battery of eight neuropsychological tests was administered preoperatively and repeated 4-7 weeks after surgery. Analysis of the change in neuropsychological test scores from baseline was used to determine the effect of treatment. Results Neuropsychological assessments were completed in 219 patients (110 clomethiazole; 109 placebo). The mean plasma concentration of clomethiazole during surgery was 66.2 microm. There was no difference between the clomethiazole and placebo group in the postoperative change in neuropsychological test scores. Conclusion Clomethiazole did not improve cerebral outcome following coronary artery bypass surgery.