Hypofibrinogenemia can be estimated by the predictive formula in aortic surgery

Objective Aortic surgery often causes massive bleeding due to hypofibrinogenemia. Predicting hypofibrinogenemia is useful for developing a hemostasis strategy, including preparing for blood transfusion. We made a formula for predicting the serum fibrinogen level (SFL) at the termination of cardiopulmonary bypass (CPB) in aortic surgery and examined its validity. Methods We performed a retrospective observational study that consisted of 267 patients (group A) who underwent aortic surgery from July 2013 to December 2016 and made a formula for predicting the SFL at the termination of CPB in group A by a multiple linear regression analysis. The validity of this formula was then examined in another 60 patients (group B) who underwent aortic surgery from January 2017 to December 2017. Results We developed the following predictive formula: SFL at the termination of CPB (mg/dL) = 14.7 + 0.44 × preoperative SFL (mg/dL) + (− 0.14) × CPB time (min) + 0.64 × preoperative body weight (kg) + (− 17.3) × lateral thoracotomy (Yes/No, Yes: 1, No: 0). In group B, the predictive formula proved to be statistically valid in group B ( R 2 = 0.531, p