Four-Group Classification Based on Fibrinogen Level and Fibrin Polymerization Associated with Postoperative Bleeding in Cardiac Surgery

Fibrinogen and fibrin formation have a key role in perioperative hemostasis. The aim of this study is to examine the association of postoperative hemostasis with a combined evaluation of the fibrinogen level and fibrin polymerization in cardiac surgery. We retrospectively classified 215 consecutive cardiac surgery patients into 4 groups (Fuji-san classification) that were divided by fibrinogen level <150 mg/dL (ie, hypofibrinogenemia) and fibrinogen thromboelastometry value at 10 minutes with rotational thromboelastometry <6 mm (ie, low fibrin polymerization) at the warming of cardiopulmonary bypass. Four groups resulted; group I, the acceptable range (n = 85); group II, only hypofibrinogenemia (<150 mg/dL, ≥6 mm, n = 63); group III, hypofibrinogenemia and low fibrin polymerization (<150 mg/dL, <6 mm, n = 60); and group IV, only low fibrin polymerization (≥150 mg/dL, <6 mm, n = 7). The risk of chest tube drainage volume greater than 500 mL within the first 24 hours after surgery (with group I as the reference) was increased in group II (odds ratio [OR], 3.3; 95% confidence interval [CI], 1.5-7.4; P <.01) and group III (OR, 8.5; 95% CI, 3.5-21.7; P <.01), and the risk greater than 1000 mL (with group I as the reference) was increased in group III (OR, 4.0; 95% CI, 1.1-17.3; P =.03) and group IV (OR, 23.1; 95% CI, 3.2-201.0; P <.01). Intraoperative blood transfusions were decreased by 24.5%, after stratifying the starting amount of fresh frozen plasma by the 4-group classification in the recent consecutive 65 (30.2%) patients (P <.01). The 4-group classification is associated with postoperative bleeding and may improve the quality of perioperative blood transfusion in cardiac surgery.