Bench-to-bedside review: Optimising emergency reversal of vitamin K antagonists in severe haemorrhage - from theory to practice

Abstract

Critical care physicians are increasingly facing patients receiving oral anticoagulation for either cessation of major haemorrhage or to reverse the effects of vitamin K antagonists ahead of emergency surgery. Rapid reversal of anticoagulation is particularly essential in cases of life-threatening bleeding. In these situations, guidelines recommend the concomitant administration of prothrombin complex concentrates (PCCs) and oral or intravenous vitamin K for the fastest normalisation of the international normalised ratio (INR). Despite their universal recommendation, PCCs remain underused by many physicians who prefer to opt for fresh frozen plasma despite its limitations in anticoagulant reversal, including time to reverse INR and high risk of transfusion-related acute lung injury. In contrast, the lower volume required to normalise INR with PCCs and the room temperature storage facilitate faster preparation and administration time, thus increasing the speed at which haemorrhages can be treated. PCCs therefore allow faster, more reliable and complete reversal of vitamin K anticoagulation, especially when administered immediately following confirmation of haemorrhage. In the emergency setting, probabilistic dosing may be considered.

Figure 1

Cumulative bleeding of patients receiving warfarin [5]. Reproduced with permission from Lippincott Williams & Wilkins ()

Figure 2

Calculation of prothrombin complex concentrate dose for anticoagulant reversal in bleeding patients [2]. The proposed 'calculation of dose' method is difficult to manage in an emergency situation when immediate normalisation of the international normalised ratio (INR) is required to stop life-threatening bleeding. Reproduced with permission from Massachusetts Medical Society.

Figure 3

Algorithm for anticoagulant reversal with prothrombin complex concentrates. INR, international normalised ratio; PCC, prothrombin complex concentrate.