Background: Fluid resuscitation after traumatic injury may necessitate coagulation factor replacement to prevent bleeding complications of dilutional coagulopathy. Recombinant activated factor VII (rFVIIa) is being widely investigated as a hemostatic agent in trauma. Multicomponent therapy with prothrombin complex concentrate (PCC) containing coagulation factors II, VII, IX, and X might offer potential advantages.
Methods: Anesthetized mildly hypothermic normotensive pigs were hemodiluted by substituting 65% to 70% of total blood volume in phases with hydroxyethyl starch and red cells. Thereafter, animals received 12.5 mL . kg isotonic saline placebo, 35 IU . kg PCC, or 180 microg x kg rFVIIa. Immediately afterward, a standardized spleen injury was inflicted, and prothrombin time (PT) and hemostasis were assessed. Thrombin generation was also determined.
Results: Hemodilution depleted levels of factors II, VII, IX, and X markedly, prolonged PT and decreased thrombin formation. PCC and rFVIIa both fully normalized the hemodilution-induced lengthening of PT. In PCC recipients, peak thrombin generation was greater by a median of 60.7 nM (confidence interval 56.4-64.9 nM) compared with the rFVIIa group (p = 0.008). After spleen trauma, time to hemostasis was shortened to a median of 35 minutes in animals treated with PCC versus 94 minutes with rFVIIa (p = 0.016).
Conclusions: In a pilot study involving an in vivo large-animal model of spleen trauma, PCC accelerated hemostasis and augmented thrombin generation compared with rFVIIa. Further investigations are warranted on PCC as a hemostatic agent in trauma.