Effects of different fibrinogen concentrations on blood losss and coagulation parameters in a pig model of coagulopathy with blunt liver injury

Introduction: The early application of fibrinogen could potentially reverse haemodilution-induced coagulopathy, although the impact of varying concentrations of fibrinogen to reverse dilutional coagulopathy has not been studied in vivo. We postulated that fibrinogen concentration is correlated with blood loss in a pig model of coagulopathy with blunt liver injury. Methods: Coagulopathy was induced in 18 anaesthetized pigs (32 +/- 1.6 kg body weight) by replacing 80% of blood volume with hydroxyethylstarch 130/0.4 and Ringer's lactated solution, and re-transfusion of erythrocytes. Animals were randomly assigned to receive either 70 mg kg(-1) (F-70) or 200 mg kg(-1) (F-200) fibrinogen or placebo before inducing blunt liver injury using a force of 225 +/- 26 Newton. Haemodynamics, coagulation parameters and blood loss were monitored for 2 hours. After death, histological examination of internal organs was performed to assess the presence of emboli and the equality of liver injury. Results: Plasma dilution caused severe coagulopathy. Measured by thromboelastography fibrinogen restored coagulation dose-dependently. Total blood loss was significantly lower and survival better in both fibrinogen groups as compared to controls (P < 0.05). Between the F-70 (1317 +/- 113 ml) and the F-200 group (1155 +/- 232 ml) no significant difference in total blood loss could be observed, despite improved coagulation parameters in the F-200 group (P < 0.05). Microscopy revealed even injury pattern and no (micro) thrombi for either group. Conclusions: Restoring fibrinogen with 70 or 200 mg kg(-1) after severe dilutional coagulopathy safely improved coagulation and attenuated blood loss after experimental blunt liver trauma. The higher dosage of fibrinogen was not associated with a further reduction in blood loss.