Methylprednisolone in neonatal cardiac surgery: reduced inflammation without improved clinical outcome

Abstract

Background: Corticosteroids are widely used in pediatric open-heart surgery to reduce systemic inflammatory response and to mediate possible cardioprotective effects. However, the optimal dosing of corticosteroids is unknown and their administration varies considerably between different institutions.

Methods: Forty neonates undergoing open-heart surgery were randomized in a double-blind fashion equally into 2 groups. After the induction of anesthesia, 1 group received 30 mg/kg intravenous methylprednisolone and the other a placebo. Concentrations in plasma of interleukin 6 (IL-6), IL-8, IL-10, free methylprednisolone and total methylprednisolone were obtained for the following: (1) at anesthesia induction before the study drug was administered; (2) 30 minutes on cardiopulmonary bypass; (3) 5 minutes after protamine administration; and (4) 6 hours after weaning from cardiopulmonary bypass. Troponin T was measured at time points T1, T3, T4, and also at 6:00 on the first postoperative morning. Physiological and clinical outcome parameters were also recorded.

Results: Intravenous methylprednisolone resulted in high plasma drug concentrations that peaked at T2. Methylprednisolone significantly lowered concentrations of proinflammatory cytokines IL-6 and IL-8 and raised levels of anti-inflammatory IL-10. No significant differences in troponin T levels were detected. Blood glucose levels were significantly higher in the methylprednisolone group, and patients in this group received more often insulin therapy than controls. No significant differences were observed in other clinical or physiological outcome measurements.

Conclusions: Intravenous 30 mg/kg methylprednisolone administered before cardiopulmonary bypass resulted in high effective plasma drug concentrations and a decreased inflammatory response. However, no cardioprotective effect or better clinical outcome was noticed.