Prevention of reperfusion tachyarrhythmia after CABG: magnesium versus lidocaine

Abstract

Background Reperfusion tachyarrhythmia after aortic cross-clamp (ACC) release is one of the most commonly encountered complications after coronary artery bypass grafting (CABG) surgery, and its control may save these patients. Materials and methods Ninety patients who had undergone CABG surgery were enrolled in this study. Patients were assigned randomly to three groups (30 patients each). The lidocaine group (LIDO) group received lidocaine (2 mg/kg) in 100 ml isotonic saline, the magnesium group (MAGN) group received magnesium (30 mg/kg) diluted in 100 ml of an isotonic saline 0.9% solution, and the control group received 100 ml normal saline by a pump circuit 3-5 min before ACC release. Anesthetic management, weaning protocol from cardiopulmonary bypass, was standardized. All the patients were monitored after the release of ACC and electrical rhythms (including ventricular fibrillation and supraventricular tachyarrhythmia) were recorded. Results Incidences of postrelease of ACC and ventricular fibrillation were lower in the lidocaine and magnesium groups compared with the control group [7 (23%), 4 (13%) vs. 11 (36%)] ( P = 0.042). Also, the incidence of an atrioventricular block postrelease ACC was higher in the lidocaine group compared with the magnesium and control groups [7 (23%) vs. 2 (6%) and 3 (10%), respectively] ( P = 0.039). The need for a temporary pace maker was higher in the lidocaine group compared with the magnesium and control groups [7 (23%) vs. 2 (6%) and 1 (3%), respectively] ( P = 0.044). Also, the total duration of ICU stay was shorter in the magnesium group compared with the lidocaine and control groups. Conclusion The administration of lidocaine and magnesium sulfate before the release of ACC reduced the incidence of ventricular fibrillation. The administration of magnesium shortened the ICU stay in adult patients undergoing CABG surgery by cardiopulmonary bypass. However, the administration of Lidocaine was associated with more transient atrioventricular block.