How long should warfarin (Coumadin) be held before a procedure?

Warfarin Discontinuation Before Procedures

For high-risk procedures, stop warfarin 5 days before the procedure and verify INR <1.5 immediately prior to the procedure. 1

Risk Stratification Framework

High-Risk Procedures (require warfarin discontinuation)

• Polypectomy, endoscopic mucosal resection/submucosal dissection 1
• ERCP with sphincterotomy, ampullectomy 1
• Endoscopic therapy of varices, stricture dilation 1
• Percutaneous endoscopic gastrostomy 1
• EUS with fine needle aspiration or interventional therapy 1
• Most surgical procedures requiring general anesthesia 2, 3

Low-Risk Procedures (continue warfarin)

• Diagnostic endoscopy with or without biopsy 1
• Biliary or pancreatic stenting without sphincterotomy 1
• Device-assisted enteroscopy without polypectomy 1
• Breast core needle biopsy 2

Management Protocol for High-Risk Procedures

Patients at LOW Thrombotic Risk

Stop warfarin 5 days before the procedure 1

• Check INR on the day before or morning of procedure to ensure <1.5 1
• Resume warfarin at usual maintenance dose on the evening of the procedure 1
• Check INR one week later to confirm therapeutic anticoagulation 1
• Do NOT routinely give vitamin K if INR is 1.5-1.9 measured 1-2 days before surgery 4

Patients at HIGH Thrombotic Risk

High-risk conditions include: prosthetic metal heart valve (especially mitral position), AF with mitral stenosis, AF with prior stroke/TIA, recent VTE (within 3 months), or CHADS₂ score ≥5 1, 3

Stop warfarin 5 days before the procedure AND bridge with LMWH 1

• Stop warfarin 5 days before procedure 1
• Start therapeutic-dose LMWH 2 days after stopping warfarin (approximately 3 days before procedure) 1, 5
• Give last dose of LMWH at least 24 hours before the procedure 1
• Check INR prior to procedure to ensure <1.5 1
• Resume warfarin at usual dose on evening of procedure 1
• For high bleeding risk procedures, delay LMWH restart for 48-72 hours post-procedure 3
• For low bleeding risk procedures, restart LMWH at previous dose within 24 hours 3
• Continue LMWH until INR therapeutic for 2 consecutive days 1

Management Protocol for Low-Risk Procedures

Continue warfarin without interruption 1

• Check INR during the week before the procedure 1
• If INR is within therapeutic range, continue usual daily dose 1
• If INR is above therapeutic range but <5, reduce daily dose until INR returns to therapeutic range 1
• If INR >5, defer the procedure and contact anticoagulation clinic for management 1

Critical Pitfalls to Avoid

Assuming 5 days is always sufficient without verification leads to preventable complications - approximately 7% of patients still have INR >1.5 after 5 days of warfarin discontinuation 3

Resuming full-dose LMWH too early post-procedure causes major bleeding in up to 20% of patients 3

Giving routine vitamin K for INR 1.5-1.9 measured 1-2 days before surgery is not recommended - this causes post-operative warfarin resistance without proven benefit 4

Proceeding without INR verification, especially for neuraxial procedures, risks catastrophic epidural hematoma 3, 6

Elderly patients may require longer warfarin interruption periods due to delayed decay of anticoagulant effect 2, 3

Special Considerations

• Patients with mechanical heart valves require careful bridging protocols, as safety data is less robust in this population 5
• All patients on warfarin have increased post-procedure bleeding risk compared to non-anticoagulated patients 1
• For procedures requiring spinal/epidural anesthesia, INR verification is mandatory 3
• Consider lower starting doses of LMWH (200-400 units/hour) immediately post-procedure for high bleeding risk cases 7