Estimation of Fibrinogen Concentration During Extracorporeal Circulation in Pediatric Cardiac Surgery

Maintenance of adequate fibrinogen levels during cardiopulmonary bypass (CPB) is important in assuring adequate post-CPB hemostasis. Fresh frozen plasma (FFP) is used in the pediatric CPB circuit as a prime constituent as a source of coagulation factors, including fibrinogen; yet the resultant on-CPB fibrinogen concentration is related to multiple factors. Accurate formulas for predicting post-dilutional fibrinogen levels and the minimal FFP volume to prime the extracorporeal circuit (ECC) to maintain post-dilutional fibrinogen levels greater than 100 mg/ dL were developed prospectively from seventy-five infant and pediatric patients. The patients weighed less than twenty-five kilograms and underwent CPB for the correction of various congenital cardiac anomalies. Variables expected to affect fibrinogen level were: height, weight, body surface area, pre-dilutional hematocrit, pre-dilutional fibrinogen concentration, patient circulating blood volume, circuit priming volume, FFP volume added to the prime pre-CPB, pre-CPB blood loss, and volume added by anesthesia pre-CPB. Equations to predict the post-dilutional fibrinogen value and the minimal volume of FFP to add to the ECC prime were formulated using multiple linear regression with the results shown in the tables below. VARIABL