Effect of timing and route of methylprednisolone administration during pediatric cardiac surgical procedures

Abstract

Background: We compared the antiinflammatory and cardioprotective effects of the two most common regimens of corticosteroid administration in pediatric cardiac surgical procedures: a single dose delivered either at anesthesia induction or by cardiopulmonary bypass (CPB) prime.

Methods: Forty-five children, aged between 1 and 18 months and undergoing ventricular septal or atrioventricular septal defect correction, were randomized in double-blind fashion into three groups. The anesthesia induction group received 30 mg/kg methylprednisolone intravenously after anesthesia induction, and the CPB-prime group received 30 mg/kg methylprednisolone by CPB circuit. The placebo group received saline solution. Plasma concentrations of methylprednisolone, interleukin (IL)-6, IL-8 and IL-10, and troponin were measured at anesthesia induction before the study drug, 30 minutes on CPB, after patients were weaned from CPB, and 6 hours after cessation of CPB.

Results: Equally high methylprednisolone concentrations were detected in both methylprednisolone groups, but the measured peak concentration occurred earlier in the induction group. Significantly lower IL-8 concentrations were observed just after patients were weaned from and 6 hours after CPB in the anesthesia induction group compared with the placebo (p = 0.002, p = 0.001) and prime groups (p = 0.003, p = 0.006). Significant reductions of troponin were detected in both methylprednisolone groups compared with placebo (induction, p = 0.001; prime, p = 0.002) 6 hours after patients were weaned from CPB.

Conclusions: Methylprednisolone administration at anesthesia induction was superior in terms of antiinflammatory action. Methylprednisolone administration in CPB-prime only a few minutes before aortic cross-clamping and cardioplegia resulted in mean troponin reductions similar to those of administration at anesthesia induction. Corticosteroids may have direct cardioprotective properties, as reported in experimental studies.