Reversing Rivaroxaban Anticoagulation as Part of a Multimodal Hemostatic Intervention in a Polytrauma Animal Model

Abstract

Background: Life-threatening bleeding requires prompt reversal of the anticoagulant effects of factor Xa inhibitors. This study investigated the effectiveness of four-factor prothrombin complex concentrate in treating trauma-related hemorrhage with rivaroxaban-anticoagulation in a pig polytrauma model. This study also tested the hypothesis that the combined use of a low dose of prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate could improve its subtherapeutic effects.

Methods: Trauma (blunt liver injury and bilateral femur fractures) was induced in 48 anesthetized male pigs after 30 min of rivaroxaban infusion (1 mg/kg). Animals in the first part of the study received prothrombin complex concentrate (12.5, 25, and 50 U/kg). In the second part, animals were treated with 12.5 U/kg prothrombin complex concentrate plus tranexamic acid or plus tranexamic acid and fibrinogen concentrate. The primary endpoint was total blood loss postinjury. The secondary endpoints (panel of coagulation parameters and thrombin generation) were monitored for 240 min posttrauma or until death.

Results: The first part of the study showed that blood loss was significantly lower in the 25 U/kg prothrombin complex concentrate (1,541 ± 269 ml) and 50 U/kg prothrombin complex concentrate (1,464 ± 108 ml) compared with control (3,313 ± 634 ml), and 12.5 U/kg prothrombin complex concentrate (2,671 ± 334 ml, all P < 0.0001). In the second part of the study, blood loss was significantly less in the 12.5 U/kg prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate (1,836 ± 556 ml, P < 0.001) compared with 12.5 U/kg prothrombin complex concentrate plus tranexamic acid (2,910 ± 856 ml), and there were no early deaths in the 25 U/kg prothrombin complex concentrate, 50 U/kg prothrombin complex concentrate, and 12.5 U/kg prothrombin complex concentrate plus tranexamic acid and fibrinogen concentrate groups. Histopathologic analyses postmortem showed no adverse events.

Conclusions: Prothrombin complex concentrate effectively reduced blood loss, restored hemostasis, and balanced thrombin generation. A multimodal hemostatic approach using tranexamic acid plus fibrinogen concentrate enhanced the effect of low doses of prothrombin complex concentrate, potentially reducing the prothrombin complex concentrate doses required for effective bleeding control.