Perioperative course of FXIII in children undergoing major surgery

Background: Acquired deficiency of FXIII because of perioperative hemodilution has been described several times in adults; however, data in children are scarce. We performed a prospective observational trial to evaluate the intraoperative course of FXIII in children undergoing elective major surgery. Methods: Blood samples were repeatedly taken from 46 children aged 0.316 years undergoing major surgery. Concentrations of FXIII and fibrinogen, thrombelastometry by ROTEM (R), and cell count were assessed intraoperatively. Results: A significant decrease in FXIII concentration (median 60%; IQR 49-69%) was already noted at beginning of surgical procedures, while most ROTEM (R) traces remain unchanged. FXIII levels further deteriorated intraoperatively to minimal levels of 33% (15-61%). Lowest intraoperative clot strength (ExTEM) was 44 mm (3450 mm), and fibrinogen plasma levels decreased to minimal levels of 130 mg.dl-1 (95-160 mg.dl-1). In 43 of 46 children, transfusion therapy was necessary. Despite of transfusion of fresh frozen plasma (cumulative total dose 22 ml.kg-1 [11-32 ml.kg-1]) in 21 of 46 children, FXIII level remains low in all children till the end of surgery at levels of 39% (20-46%). Conclusions: Coagulation factor XIII decreased early during major surgery owing to hemodilution. Overall intraoperative FXIII levels remain low despite of transfusion of fresh frozen plasma.