Coagulopathies in children after cardiopulmonary bypass (CPB) are complex. There are very limited data correlating coagulation tests with postoperative bleeding. We evaluated coagulation changes after CPB and after the administration of coagulation products to 75 children. Baseline coagulation tests were obtained and repeated after protamine administration, after transfusion of individual coagulation products, and on arrival in the intensive care unit (ICU). Regression analysis demonstrated no baseline coagulation test to predict postoperative chest tube drainage. Weight and duration of CPB were determined to be the only predictors of bleeding. Further analyses demonstrated that children <8 kg had more bleeding and required more coagulation products than children >8 kg. Postprotamine platelet count and fibrinogen level correlated independently with 24-h chest tube drainage in children <8 kg, whereas postprotamine platelet count and thrombelastographic values did so in patients weighing >8 kg. Platelet administration alone was found to restore effective hemostasis in many patients. With ongoing bleeding, cryoprecipitate improved coagulation parameters and limited blood loss. Fresh-frozen plasma administration after platelets worsened coagulation parameters and was associated with greater chest tube drainage and more coagulation product transfusions in the ICU. Objective data to guide post-CPB component therapy transfusion in children are suggested.
Implications: Children <8 kg can be expected to have more severe coagulopathies, require more coagulation product transfusions, and bleed more after cardiopulmonary bypass. Correlations between coagulation tests and postoperative chest tube drainage are defined. Platelets and, if necessary, cryoprecipitate optimally restore hemostasis. Fresh-frozen plasma offers no benefits in correcting postcardiopulmonary bypass coagulopathies in children.