Invited Commentary: Achieving Post-Bypass Hemostasis in Young Children: At What Cost?

Young children requiring bypass often develop coagulopathy resulting in major postoperative blood loss. Increased post-bypass bleeding and donor exposures are independently associated with adverse outcomes. When transfusion of hemostatic blood products fails to reduce bleeding to an acceptable level, rescue therapies including prothrombin complex concentrates (PCCs), and/or recombinant activated factor VII are being given "off-label" with increasing frequency. A number of studies attempting to determine the safety and efficacy of PCCs in neonates and young children are being published. These studies are most commonly retrospective, observational, performed in a single center with varying doses, indications for, and timing of administration in a small number of patients with varying results. The results of these individual studies are questionable and are not to be generalized to other center's patients. Because factor VIII inhibitor bypassing activity (FEIBA) contains the activated form of factor VII and factor X there are concerns regarding the potential for thrombotic events in a population with a known risk of postoperative thromboembolism. Currently, there is no validated assay with which to measure the efficacy of FEIBA in vivo to determine dose titration. Well-designed multicenter randomized control trials are needed to determine the optimal dose and risk-benefit of PCCs after pediatric cardiac surgery. Until such data are available the decision to give a procoagulant to neonates and young children after bypass needs to be made when the consequences of blood loss and replacement pose more risk than the risk of thrombotic complications from the drug.