Predict postoperative bleeding after cardiopulmonary bypass in children

Abstract

Background: Systemic coagulation disorders after cardiac surgery requiring cardiopulmonary bypass (CPB) represent serious postoperative complications. The aim of the present study was to investigate the relationship between postoperative hemorrhage and coagulation parameters determined by global coagulation assays, to define predictive markers. Methods: Thirty-four pediatrics were enrolled for the admitted patients to the University Children’s Hospital from Brussels for cardiac surgery with CPB. Blood samples were collected ten minutes after protamine administration. Laboratory investigations included platelet count, fibrinogen level and classical coagulation tests (prothrombin time (PT) with International Normalized Ratio (INR), activated partial thromboplatin time (a PTT)). The duration of cardiopulmonary bypass and the minimal temperature were recorded. Chest tube drainage was monitored for 24 h after operations as an index of postoperative hemorrhage (> 10 ml/kg). Results: Demographic data differed between the hemorrhagic and non hemorrhagic group. In this study the incidence of bleeding was 64.7%, and it was higher in younger children with lower body weight. No baseline coagulation test was found by correlation coefficient to be predictive or, to correlate with postoperative chest tube drainage (PT (INR), p=0.48; a PTT, p=1.00). After the protamine administration to patients, platelet count (p=1.00) and fibrinogen level (p=0.278) did not correlate with eventual chest tube drainage. Our investigation determined the duration of CPB (r (Pearson) = 0.53; p=0.0008) and the minimal temperature while CPB (r (Spearman) = -0.39; p=0.002) to be predictive for 24-hour chest tube drainage after CPB in children. Conclusions: By using regression analysis, we found duration and minimal temperature of CPB to be predictors of post-CPB chest tube drainage in children. No baseline coagulation test was found to be predictive with postoperative bleeding. Postprotamine platelet count and fibrinogen level were observed to not correlate with chest tube drainage.