Guidelines for the management of an elevated INR ^[A1]

 

General points

·        Bleeding risk increases exponentially from INR 5 to 9.

 

·        Any INR≥6 requires close monitoring, for example daily INR if no active bleeding until INR <5

 

·        It takes 6-12 hours for vitamin K to reduce the INR

 

·        See the table below to guide therapy for an elevated INR

 

·        *High bleeding risk patients include

o       active gastrointestinal disorders (e.g. peptic ulcer disease, inflammatory bowel disease)

o       concomitant antiplatelet (eg aspirin, clopidogrel) or anticoagulation (eg enoxaparin/heparin) therapy

o       major surgical procedure in preceeding two weeks

o       Low platelet count (<50)

 

·        In all situations, carefully reassess the need for ongoing anti-coagulation therapy

o       The use of anticoagulants is based on an assessment of relative thrombotic and bleeding risk.  After every serious bleed, reassessment is required and a decision to stop anticoagulation may be appropriate in some patients.  If you have any queries about this please discuss with a haematologist.

o       Recurrence rates after major bleeds are 30 – 50%.

o       Consider aspirin as a safer alternative in patients with AF who have a major bleed.

o       In patients who need to have warfarin continued, closer monitoring of the INR is required to avoid future episodes of over-anticoagulation.

 

 

 

 

 

Guide to the management of over-anticoagulation with warfarin

 

 

INR <5 Bleeding absent	Lower dose/omit dose of warfarin Re-start when INR in therapeutic range If the INR is only minimally above the therapeutic range (up to 10%), dose reduction may not be necessary
INR 5-9 Bleeding absent	Stop warfarin, investigate rise in INR and patient-specific factors *High bleeding risk-vitamin K (1 to 2mg orally or 0.5 to 1mg IV) Measure INR within 24 hours, resume warfarin at reduced dose once INR in the therapeutic range
INR >9 Bleeding absent	Low bleeding risk Stop warfarin. Give 2.5mg to 5mg vitamin K orally or 1mg vit K IV. Measure INR in 6 to 12 hours, restart warfarin at reduced dose when INR <5 *High bleeding risk Stop warfarin Give 1mg Vitamin K IV Consider Prothrombinex-HT (25-50IU/kg) and fresh frozen plasma/FFP  (150-300mL) Measure INR in 6-12 hours Resume warfarin at reduced dose when INR <5
Any clinically significant bleeding	Stop warfarin give 5-10mg IV vitamin K, Give Prothrombinex-HT (25-50IU/kg) and fresh frozen plasma/FFP  (150-300mL) Assess patient continuously until INR <5 and bleeding stops   If FFP unavailable, use 25-50 IU/kg prothrombinex if prothrombinex unavailable, use 10-15mL/kg fresh frozen plasma

 

 

 

·        Click here to link to the

o       Duration and Intensity of Anti-coagulation section of the guidelines

o       Risk Factors for Bleeding section of the guidelines