25th June 2023

Reversal of anticoagulation

Patients taking long term antiplatelet and anticoagulant medication (such as warfarin or direct oral anticoagulants (DOACs)) are at particular risk of intracranial haemorrhage following head injury. In managing these patients, it is important to consider the possibility of anticoagulant reversal. Some anticoagulants, such as warfarin, have specific antidotes that can be used to reverse their anticoagulant effect. Many patients presenting with life threatening intracranial haemorrhage whilst taking anticoagulants will warrant discussion with haematology to help guide anticoagulant reversal. The indication for antiplatelet and anticoagulant agents will influence ‘risk versus benefit’ decisions surrounding stopping these medications.

Warfarin reversal guidelines

UK guidelines from the British National Formulary and British Society of Haematology advise the following regarding warfarin management in the context of bleeding or raised INR.

• Major bleeding: Stop warfarin, give vitamin K IV; give prothrombin complex (PCC) (factors II, VII, IX, and X); if dried prothrombin complex is unavailable, fresh frozen plasma can be given but is less effective
• INR >8.0, minor bleeding: Stop warfarin; give vitamin K IV; repeat dose of vitamin K if INR still too high after 24 hours; restart warfarin when INR <5.0
• INR >8.0, no bleeding: Stop warfarin; give vitamin K by mouth using the intravenous preparation orally, repeat dose of vitamin K if INR still too high after 24 hours; restart warfarin when INR <5.0
• INR 5.0–8.0, minor bleeding: Stop warfarin, give Vitamin K, and restart warfarin when INR <5.0
• INR 5.0–8.0, no bleeding: Withhold 1 or 2 doses of warfarin and reduce subsequent maintenance dose

Reversal of DOACs

Reversal agents are available for dabigatran etexilate, apixaban and rivaroxaban.

• Idarucizumab is licensed for the rapid reversal of dabigatran in life-threatening or uncontrolled bleeding
• Andexanet alfa is licensed for the reversal of apixaban or rivaroxaban in life-threatening or uncontrolled bleeding