In an adult patient, how many days before an elective surgery should warfarin be stopped, and how many hours before surgery should apixaban (and other direct oral anticoagulants) be discontinued, taking into account the procedure’s bleeding risk and the patient’s renal function?

Perioperative Anticoagulation Discontinuation Timing

For warfarin, stop 5 days before elective surgery; for apixaban and other direct oral anticoagulants (DOACs) with normal renal function, stop 2 days (48 hours) before high-risk procedures and omit only the morning dose for low-risk procedures.

Warfarin Management

Preoperative Discontinuation

• Stop warfarin 5 days before the procedure to allow sufficient time for the INR to decrease to ≤1.5, which is the target for safe surgery 1, 2
• Check the INR on the day before surgery to confirm it is <1.5; if the INR remains ≥1.8, administer low-dose oral vitamin K (1-2.5 mg) for reversal 1
• For elderly patients or those with high-intensity INR ranges (3.0-4.0), consider a longer interruption period beyond 5 days 1

Bridging Anticoagulation

• Bridging with low molecular weight heparin (LMWH) is NOT routinely indicated for most patients, including those with atrial fibrillation 2
• Bridging is only indicated for patients with recent (<3 months) venous thromboembolism, pulmonary embolism, or mechanical heart valves 2
• When bridging is required: start therapeutic-dose LMWH 2 days after stopping warfarin, with the last LMWH dose given at least 24 hours before the procedure 1

Postoperative Resumption

• Resume warfarin on the day of the procedure or the evening after surgery at the usual maintenance dose 1
• For high bleeding-risk procedures, wait 48-72 hours after surgery before restarting warfarin once adequate hemostasis is achieved 2

Direct Oral Anticoagulants (Apixaban, Rivaroxaban, Edoxaban)

Normal Renal Function (CrCl ≥50 mL/min)

High-Risk Procedures

• Stop apixaban, rivaroxaban, or edoxaban 3 days (72 hours) before the procedure, which allows 4-5 half-lives to elapse and ensures minimal residual anticoagulant effect 1, 2
• High-risk procedures include major surgery, neuraxial blockade, neurosurgery, spinal surgery, major orthopedic surgery, and cardiac surgery 3

Low-Risk Procedures

• Omit only the morning dose on the day of the procedure, or stop the DOAC 1 day (24 hours) before if preferred 1, 2
• Low-risk procedures include dental extractions, colonoscopy with biopsy, cataract surgery, and minor dermatologic procedures 1, 3

Impaired Renal Function (CrCl 30-50 mL/min)

• Stop apixaban and rivaroxaban 3 days before high-risk procedures due to their 25-33% renal clearance 2
• For low-risk procedures, stop 2 days before the procedure 2

Postoperative Resumption

• After low-risk procedures, restart DOACs at full dose 24 hours postoperatively once adequate hemostasis is confirmed 3, 4
• After high-risk procedures, restart DOACs 48-72 hours postoperatively once hemostasis is established 2, 3
• Do NOT use bridging anticoagulation with heparin or LMWH when interrupting DOACs, as this increases major bleeding risk (6.5% vs 1.8%) without reducing thrombotic events 3, 4

Dabigatran (Renal-Dependent DOAC)

Normal Renal Function (CrCl ≥50 mL/min)

• Stop dabigatran 2 days (48 hours) before high-risk procedures (skip 4 doses), allowing 4-5 half-lives to elapse 3
• For low-risk procedures, stop 1 day (24 hours) before (skip 2 doses) 3, 4

Impaired Renal Function (CrCl 30-50 mL/min)

• Stop dabigatran 5 days (120 hours) before high-risk procedures due to its 80% renal elimination and prolonged half-life in renal impairment 1, 2, 3
• For low-risk procedures, stop 2 days before 3

Postoperative Resumption

• After low-risk procedures, restart dabigatran 24 hours postoperatively at full dose (150 mg twice daily) 3
• After high-risk procedures, restart 48-72 hours postoperatively 3
• For high thrombotic risk patients, consider a reduced dose (110-150 mg once daily) on the evening of surgery before returning to full dosing 3

Critical Decision-Making Algorithm

Step 1: Assess Renal Function

• Calculate creatinine clearance (CrCl) or use eGFR to determine drug clearance capacity 1, 2

Step 2: Classify Procedure Bleeding Risk

• High-risk: Major abdominal, orthopedic, neurosurgery, cardiac surgery, neuraxial anesthesia, polypectomy 1, 3
• Low-risk: Dental extractions, cataract surgery, diagnostic endoscopy, minor dermatologic procedures 1, 3

Step 3: Apply Discontinuation Timeline

• Warfarin: Always 5 days regardless of procedure risk 1, 2
• Apixaban/Rivaroxaban/Edoxaban: 3 days for high-risk, morning dose omission for low-risk (normal renal function) 1, 2
• Dabigatran: 2 days for high-risk with normal renal function; 5 days for high-risk with CrCl 30-50 mL/min 1, 2, 3

Step 4: Verify Anticoagulation Status Before Procedure

• For warfarin: Check INR day before surgery (target <1.5) 1
• For dabigatran: Thrombin time (TT) or dilute thrombin time (dTT) if available; normal TT excludes significant dabigatran levels 3
• Do NOT use PT/INR to assess DOAC levels—these tests are insensitive to DOACs 3

Common Pitfalls and How to Avoid Them

• Pitfall: Using bridging anticoagulation routinely for atrial fibrillation patients

  • Solution: Only bridge patients with recent (<3 months) VTE or mechanical heart valves 2, 3

• Pitfall: Relying on PT/INR to assess DOAC anticoagulation status

  • Solution: Use thrombin time for dabigatran; PT/INR is unreliable for DOACs 3

• Pitfall: Resuming full-dose anticoagulation too early after high-risk surgery

  • Solution: Wait 48-72 hours after high bleeding-risk procedures before restarting full-dose anticoagulation 2, 3

• Pitfall: Failing to extend discontinuation periods for dabigatran in renal impairment

  • Solution: Always calculate CrCl and extend to 5 days for CrCl 30-50 mL/min before high-risk procedures 1, 2, 3

• Pitfall: Performing neuraxial anesthesia without confirming dabigatran levels <30 ng/mL

  • Solution: Verify dabigatran concentration or use standardized interruption protocols; if uncertain and neuraxial block is essential, consider idarucizumab reversal 3