PREVENTION
High risk patients
Co-morbidity
- Affecting clotting factor synthesis, vitamin K availability or warfarin metabolism
- cardiac failure
- gastrocolic fistula
- liver disease
- malnutrition
- cholestasis
- abrupt weight reduction
- diarrhoea
- renal impairment
- thyrotoxicosis
- fever
- malignancy
- aged >75 yr
Medications
- Many. Check interactions in the BNF Appendix 1. Use an alternative agent if possible
- most antimicrobials
- concurrent anti-platelet, NSAID, SSRI or SNRI
- Over dosage (accidental or deliberate)
Referral
- Refer patients to the local anticoagulation team for regular monitoring and dosing during inpatient stay and post-discharge
MANAGEMENT
Prosthetic heart valves
- Reversal of anticoagulation may increase the risk of valve thrombosis
- in non-life, limb or sight threatening situations, discuss management with cardiothoracic unit and haematologist
Management of warfarin
- Management of over-anticoagulation depends on the INR, severity of bleeding and underlying thrombotic risk
- Major haemorrhage
- life, limb or sight threatening bleeding including high suspicion pre-imaging
- intra-cerebral bleed
- bleed with haemodynamic instability
- major trauma
- intraocular bleed (excluding subconjunctival)
- muscle bleed resulting in compartment syndrome
- pericardial bleed
- Minor haemorrhage and INR raised
- High INR without bleeding
- Include patients with a prosthetic/metallic heart valve
- If high clinical suspicion of major bleed, do not wait for INR result or imaging
- If required, activate massive haemorrhage pathway (MHP)
Obtain venous access
- Take blood for FBC, INR, APTT, Fibrinogen, U&E, LFT, G&S/crossmatching
STOP warfarin and reverse anticoagulation
- Immediate vitamin K (phytomenadione) 5 mg slow IV AND
- Octaplex® (prothrombin complex concentrate PCC)
- contact blood bank with patient's weight for direct PCC access request
No Prosthetic Heart valves fitted
- Reduce dose or temporarily discontinue warfarin
- Administer IV vitamin K (phytomenadione) 1-3 mg slow IV
- Oral bleeding - consider tranexamic acid mouthwash
- Epistaxis - consider cautery or nasal packing
Prosthetic heart valve(s) fitted
- Reversal of anticoagulation may increase the risk of valve thrombosis
- discuss management with cardiothoracic unit and haematologist
INR >8 and no Prosthetic Heart valves fitted
- Stop warfarin
- Give 2 mg oral vitamin K (phytomenadione)
- Repeat INR in 24 hr
- Restart warfarin at lower dose once INR <5.0 and monitor INR until stable
Prosthetic heart valve(s) fitted
- Reversal of anticoagulation may increase the risk of valve thrombosis
- discuss management with cardiothoracic unit and haematologist
- Consider high risk of bleeding especially if:
- aged >70, hypertension, diabetes, renal failure, previous CVA, previous GI bleed, liver disease
INR 5.0-8.0, high risk of bleeding and no Prosthetic Heart valves fitted
- Stop warfarin
- Give 2 mg oral vitamin K (phytomenadione)
- Repeat INR in 24 hr
- Restart warfarin at lower dose once INR <5.0 and monitor INR until stable
INR 5.0=8.0, low risk of bleeding and no Prosthetic Heart valves
- Withhold 1-2 doses of warfarin
- Reduce maintenance dose
Prosthetic heart valve(s) fitted
- Reversal of anticoagulation may increase the risk of valve thrombosis
- discuss management with cardiothoracic unit and haematologist
Other management
If there is a high clinical suspicion of ICH, do not wait for INR result or imaging
- Intracranial bleeding in association with warfarin therapy is a medical emergency
- urgent assessment, imaging and treatment
- seek neurosurgery advice
- Consider local, endoscopic, interventional radiological and surgical measures early for all bleeds
- Investigate cause for elevated INR
RESTARTING WARFARIN AFTER A MAJOR BLEED
- Report any patient with anticoagulation associated bleeding to hospital incident system
- Review the need for anticoagulation; confirm duration, intensity and concurrent medication
- Assess bleeding risk factors and address any potential cause for re-bleeding
- Seek specialist input from relevant team e.g. neurosurgery, gastroenterology
- Discuss with the haemostasis team before re-starting anticoagulation
- Assess suitability of alternative anticoagulants
- All cases will be reviewed by the local anticoagulation team
Date updated: 2024-06-24