C1 esterase inhibitor in pediatric cardiac surgery with cardiopulmonary bypass plays a vital role in activation of the complement system.

Our prospective study was therefore designed to determine which part of the systemic inflammatory response after cardiac operations resulted from Cardiopulmonary bypass (CPB) in neonates and infants. After approval by the human ethical committee of the Gunma Children's Medical Center (GCMC) and informed consent of the parents, 40 consecutive term congenital heart disease patients aged until 1 year who underwent long CPB time (> 3 h) at surgery were included in the prospective study between January 2012 and December 2014. C1 esterase inhibitor (C1-inh) drug (@Berinert) was generously provided by CSL Behring (King of Prussia, PA). The C1-inh (20 IU/kg) was given intravenously 60 min after CPB. Blood samples for complement factors were obtained before and 48 h after administration of C1-inh. Six patients did not survive and their data were not included. Of 34 patients included, median age was 6.5 months, median body weight was 6050 g, and 16 (47%) were female. According to the Mann-Whitney U test, there were no differences between the two groups concerning demographic and intraoperative data, postoperative chemical data. C1q concentration was only significant lower in patients with C1-inh non-treated group than in patients with C1-inh treated group. But, the consumption of C1q, C3, C4, CH50, and C1-inh in patients with C1-inhibitor non-treated group was observed early postoperatively. There is a significant difference in the values before and after C1-inh treatment between the two groups. The lower value in the C1-inh-treated group is explained by the activation of the classical pathway through the replenishment of complements by C1-inh treatment. This study proposes the administration of C1-inh is an effective therapy to reduce the activation and improve the clinical capillary leak syndrome.