The effect of recombinant factor VIIa on noncoagulopathic pigs with grade V liver injuries

BACKGROUND:Recombinant Factor VIIa (rFVIIa) has been used to decrease bleeding in a number of settings, including hemophilia, liver transplantation, intractable bleeding, and cirrhosis. It has also been shown to reduce bleeding in coagulopathic pigs with Grade V liver injuries when used as an adjunct to packing. This study was performed to determine if rFVIIa would reduce blood loss after a Grade V liver injury in noncoagulopathic pigs when used as sole therapy. STUDY DESIGN: Thirty normothermic animals were randomized to receive either 150 microg/kg of rFVIIa or normal saline intravenously. After laparotomy and splenectomy, a standardized Grade V liver injury was made with a liver clamp. Thirty seconds after injury, blinded therapy was given. Blood loss was measured 15 minutes after injury and the abdomen was closed. Animals were resuscitated to their baseline blood pressure and the study was continued for 2 hours. Serial coagulation parameters were obtained. Following the study period, blood loss was measured and an autopsy was performed. Grossly normal areas of lung were examined for evidence of intravascular thrombosis. RESULTS: Mean Factor VII:C levels increased 155-fold in the treatment group after infusion of rFVIIa. The mean prothrombin time in the treatment group decreased from 9.8 +/- 0.4 seconds to 7.3 +/- 0.2 seconds and remained significantly different from the control group throughout the study (p < 0.01). There were no differences in other coagulation parameters. Mean initial blood loss was 822 +/- 266 mL in the treatment group and 768 +/- 215 mL in the control group (p = 0.6). Rebleeding blood volume was 397 +/- 191 mL in the treatment group and 437 +/- 274 mL (p = 0.6) in the control group. Lung histology revealed no evidence of abnormal microvascular thrombosis. CONCLUSIONS:rFVIIa does not reduce blood loss after Grade V liver injury when it is used as sole therapy in warm noncoagulopathic pigs.