Systemic inflammatory response related to cardiopulmonary bypass and its modification by methyl prednisolone: high dose versus low dose

Abstract

The objective of our study was to investigate the safety and efficacy of high-dose methyl prednisolone (MP) in modifying the systemic inflammatory response (SIR) to cardiopulmonary bypass (CPB) and to compare its efficacy with low-dose MP in children undergoing cardiac surgery for congenital heart disease. Thirty children with congenital heart disease undergoing CPB were randomly assigned to two groups: group 1 (n = 15) received 30 mg/kg MP by an intravenous infusion for 30 minutes and group 2 (n = 15) received 2 mg/kg intravenously, before the onset of CPB. Postoperative clinical parameters were recorded, and serum interleukin (IL)-6 and 8 levels, acute phase reactants, and blood biochemistry were determined serially for both groups. In both groups plasma IL-6 and 8 levels were elevated above the preoperative levels at 2 and 24 hours after declamping. The peak levels were obtained at 2-hour samples. The difference between the two groups in terms of postoperative IL-6 and 8 levels was not statistically significant. C-reactive protein (CRP) levels and polymorphonuclear leukocyte counts, postoperative core temperature, duration of mechanical ventilation, period of stay in intensive care unit, oxygenation indices, and biochemical parameters of patients did not significantly differ in the two groups. Only 1 patient in group 1 had elevated liver enzymes, blood urea nitrogen, and creatinine in the postoperative period. No significant complications were observed due to treatment with high-dose MP. Although postoperative IL and CRP levels indicated a SIR in our patients, the clinical picture was apparently affected in only 1 patient and she was in the high-dose MP group. CPB initiates a SIR that is associated with an increase in neutrophil count, CRP, and IL-6 and 8 levels. High-dose (30 mg/kg) MP was not superior to low-dose (2 mg/kg) in blunting the SIR to CPB in pediatric patients undergoing open-heart surgery.