Protective effect of esmolol on myocardial ischemic injury during open heart surgery in children

OBJECTIVES: To investigate the efficacy of esmolol in protecting the myocardium from ischemia during pediatric cardiac surgery. BACKGROUND: Esmolol, an ultra-short acting beta 1-adrenoceptor blocker, reduces myocardial injury in adult cardiac operations. However, this technique is rarely used in pediatric cardiac surgery. METHODS: Thirty children with ventricular septal defect were randomly allocated to the esmolol group and the control group. Patients received intravenous esmolol (0.05 mg·kg(-1) ·min(-1) after tracheal intubation, 0.3 mg·kg(-1) ·min(-1) during cardiopulmonary bypass (CPB) and 0.03-0.05 mg·kg(-1) ·min(-1) until the end of surgery) or placebo, respectively. RESULTS: Plasma levels of creatine kinase-MB, cardiac troponin I in the esmolol group 2 min after completion of CPB, at the end of surgery, 4 h after surgery, and the first postoperative day were significantly lower than those in the control group. Values of heart rate 10 min after induction, 2 min before institution of CPB, 2 min after completion of CPB, and at the end of surgery were significantly lower in the esmolol group; however, mean arterial pressure, CPB time, cross-clamp time, and the rate of heart spontaneous rebeating were not statistically different between two groups. Cumulative postoperative dosage of dopamine in the esmolol group (100.1 ± 53.1 mg) was significantly less than that in the control group (171.4 ± 92.1 mg). CONCLUSIONS: Esmolol can protect the myocardium from ischemic injury during CPB in children and significantly reduce the use of inotropic drug.