Oral Anticoagulants

Therapeutic range (INR)

Treatment of atrial fibrillation

Treatment of deep vein thrombosis

Pulmonary embolism

Transient ischaemic attacks

Antiphospholipid syndrome

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Target 2.5 (2.0 - 3.0)

 

Recurrent deep vein thrombosis

Occurring during Warfarin treatment

Mechanical cardiac prosthetic valves

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Target 3.5 (3.0 - 4.0)

 

Tissue heart valves

Peripheral arterial disease

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not indicated

 

 Reversal of oral anticoagulant therapy

 

INR 6 - 7

INR 7 - 10

INR >10

INR >7

 

 

Without haemorrhage, withhold A/C until INR 5 then reduce dose.

Without haemorrhage, withhold A/C. Oral Vitamin K, 1-2mg.

Without or minor haemorrhage, withhold A/C. i.v. Vit. K, 2mgs.

Major haemorrhage-fresh frozen plasma, 15ml/kg(3 units =@700mls) i.v. Vit. K - 5mgs and consider Factor IX concentrate (DEFIX), 10 units/kg. Please contact Haematology M.O.

Life threatening haemorrhage

Vit. K 5mgs i.v. (slow infusion) and Factor IX concentrate, (DEFIX)

10 - 20 i.u./Kg body weight. Repeat INR after 4 hours.

 

High dose Vit. K (>5mgs) induces coumarin resistance for at least 3 days. Vitamin K i.v. may produce an anaphylactic reaction and must be given slowly! e.g. in 100mls saline over 10 mins.