Fibrinogen concentrate in dilutional coagulopathy: a dose study in pigs.

Dilutional coagulopathy can be reversed with fibrinogen concentrate. Effects of different fibrinogen dosages on clot function are not defined; high doses may increase the risk of thromboemboembolism. This study investigated the effect of six fibrinogen dosages on coagulation profile and blood loss in coagulopathic pigs. Forty-two pigs underwent a 60% hemodilution (HD) with hydroxyethylstarch (HES 130/0.4). After a standardized bone injury, animals randomly received 37.5, 75, 150, 300, 450 or 600 mg/kg fibrinogen (FGTW, LFB) or 500 ml of saline. Four hours later, a standardized liver injury was performed. Animals were then observed for two hours or until death. Blood loss was measured after death; Hemodynamic and coagulation parameters (thromboelastometry) were measured at baseline (BL), after HD, 15', 1, 2, 4 hours after fibrinogen administration and 2 hours after liver injury or right before the animals' death. Occurrence of thrombosis was examined in histological slides of internal organs. Statistical significance was set at p < 0.05. Doses of 150 mg/kg fibrinogen and higher reversed dilutional coagulopathy: Maximum clot firmness (MCF) was decreased after hemodilution (36 ± 3 mm vs. 65 ± 4 mm at BL, p < 0.05) and returned to BL after fibrinogen administration (69 ± 5 mm). Blood loss was significantly decreased with increased fibrinogen dosages: 42 ± 19 (sham), 34 ± 14 (75 mg/kg), 29 ± 13 (150 mg/kg), 28 ± 10 ml/kgbw (600 mg/kg). Fibrinogen (150-600 mg/kg) normalized clot firmness and decreased blood loss. No signs of hypercoagulability or thromboembolism were detected after high dosages.