Introduction
Craniosynostosis, a condition of premature cranial suture fusion, occurs in approximately 1 in every 2,000 births.1 These patients often need complex surgical repair to correct skull deformities, and potentially prevent functional neurologic and developmental compromise.1,2 Complex cranial vault reconstruction (CCVR) is performed primarily in infants and young children and is an intricate and high-risk procedure, often requiring extensive scalp dissection and multiple skull osteotomies.1 Children undergoing surgical correction of craniosynostosis often experience high rates of bleeding and blood product transfusion, increasing the risk of postoperative complications including mortality.3–5 The most severe and most common perioperative issues relate to the rate and extent of blood loss, which can be up to several times the patient’s total blood volume.3,6,7Contributing to high blood loss rates are the large surgical surfaces exposed, hyperfibrinolysis, and dilutional coagulopathy.6,8–10 This is a type of controlled traumatic coagulopathy for which the precise underlying mechanisms are not fully defined.3,6,8 Other reported complications include intraoperative cardiac arrest, venous air embolism, hypotension, bradycardia, postoperative seizures, surgical site infections, facial swelling with airway compromise, and unplanned postoperative mechanical ventilation.2,7,9,11–13 At our institution, approximately 30-40 children with craniosynostosis undergo CCVR each year. In the United States, ~2000 children undergo CCVR per year, representing a unique opportunity to understand and improve rates of perioperative blood loss.14
One recently endorsed strategy for decreasing blood loss in craniosynostosis repair is the intraoperative use of antifibrinolytic agents. ε-Aminocaproic acid (EACA) and tranexamic acid (TXA) are synthetic lysine analogs that block the lysine binding sites on plasminogen, resulting in antifibrinolytic activity through inhibition of plasmin formation.10,15 Antifibrinolytics have been shown to reduce transfusion needs in surgical and trauma-related bleeding.10,16 TXA has been shown to be effective in limiting blood loss in infants and children undergoing CCVR, and two recent retrospective reviews suggest a benefit of EACA in this population as well.5,14,17–19While the use of EACA and TXA to limit surgically-induced hemorrhage and transfusion requirements during CCVR has been extensively studied, the comparison of EACA vs TXA in children undergoing CCVR has not yet been evaluated. The aim of this study was to compare perioperative blood loss and need for transfusion in children receiving EACA and TXA. We hypothesized that TXA is associated with a greater decrease in blood loss and transfusion requirements when compared to EACA. A secondary aim was to identify possible laboratory predictors of blood loss in CCVR with the ultimate goal of trying to better understand surgical-induced coagulopathy in this population.