Fibrinolysis in pediatric patients undergoing cardiopulmonary bypass.
OBJECTIVE: Thromboelastographic evaluation of the influence of fibrinolysis on blood loss and blood product transfusions in children during cardiac surgery. DESIGN: Prospective study. SETTING: University-affiliated, pediatric medical center. PARTICIPANTS: Two hundred seventy-eight consecutive children undergoing cardiac surgery. INTERVENTIONS: Blood sampling for coagulation tests, including native and protamine-modified thromboelastography. MEASUREMENTS AND MAIN RESULTS: Blood coagulation tests were measured before, during, and after cardiopulmonary bypass (CPB). Demographic data, perioperative blood loss, and blood product transfusions were prospectively recorded. Fibrinolysis was defined as thromboelastography of A30/MA less than 0.85 (MA, maximum amplitude; A30, amplitude 30 minutes after MA) and was noted in 3% of children pre-CPB, 16% during CPB, and 3% post-CPB. Fibrinolysis before CPB was associated with poor cardiac output. Fibrinolysis during CPB occurred in young children (aged 350 +/- 836 days) undergoing complex surgery with prolonged CPB (119 +/- 48.8 minutes) and deep hypothermia (25.6 degrees C +/- 4.7 degrees C). These patients received blood products after CPB and were not fibrinolytic after transfusion. They incurred similar blood loss (in mL/kg) and received similar volumes of blood products (mL/kg) as age-matched and surgery-matched patients without fibrinolysis. CONCLUSION: A group of children at risk for fibrinolysis during CPB was identified. However, fibrinolysis during CPB did not influence blood loss or the total volume of blood products transfused.