Effect of dexmedetomidine on myocardial ischemia-reperfusion injury.
BACKGROUND We tested the hypothesis that depletion of neutrophil leukocytes from the cardioplegic and the initial myocardial reperfusion perfusates reduces clinical indices of reperfusion injury in patients undergoing elective coronary artery bypass. METHODS We studied 160 consecutive patients who underwent standard coronary revascularization with cardiopulmonary bypass. Patients with recent myocardial infarction or coronary angioplasty were excluded. Cold blood cardioplegia was used. Just before aortic unclamping, the hearts were perfused retrograde with 250 mL of normothermic cardioplegic solution and 750 mL of blood (pump perfusate). Patients were randomly assigned to two groups. In 80 patients (treated), neutrophils and platelets were removed from all cardiac perfusate during aortic crossclamping with leukocyte filtration. In the remaining 80 patients (control group), leukocyte filtration was not used. RESULTS There was no significant difference between groups in age, sex, severity of disease, and number of bypass grafts implanted. Treated patients showed lower prevalence of low cardiac index and reperfusion ventricular fibrillation and lower levels of creatinine kinase MB isoenzyme and troponin I early postoperatively (p < 0.05). CONCLUSIONS Neutrophil-filtered blood cardioplegia/reperfusion significantly reduced clinical and biochemical indices of myocardial reperfusion injury after elective coronary revascularization with cardiopulmonary bypass.