What are the guidelines for managing anticoagulant medications, such as warfarin (International Normalized Ratio (INR)) and direct oral anticoagulants (DOACs) like rivaroxaban (Xarelto), apixaban (Eliquis), or dabigatran (Pradaxa), before and after surgery?

Perioperative Anticoagulation Management

Direct Oral Anticoagulants (DOACs)

For patients on DOACs undergoing elective surgery, discontinue apixaban/rivaroxaban 1 day before low-to-moderate bleeding risk procedures and 2 days before high bleeding risk procedures, then resume 1 day after low-risk or 2-3 days after high-risk surgery—bridging anticoagulation is not recommended. 1, 2

Preoperative DOAC Management

High Bleeding Risk Procedures (cardiac surgery, intracranial/spinal surgery, major abdominal surgery):

• Apixaban: Stop 2 days before surgery for patients with normal/mild renal impairment, which corresponds to 4 half-lives and minimal (6%) residual anticoagulant effect 1, 2
• Rivaroxaban: Stop 48 hours (2 days) before surgery, corresponding to 4 half-lives and 6% residual effect 3
• Dabigatran: Similar timing applies based on half-life considerations 4
• For patients with moderate renal impairment (CrCl 30-50 mL/min), extend apixaban discontinuation to 4 days before high-risk surgery 1

Low-to-Moderate Bleeding Risk Procedures (arthroscopy, colonoscopy with biopsy, abdominal hernia repair):

• Apixaban: Stop 1 day before surgery, corresponding to 2-3 half-lives and 3-6% residual effect 1, 2
• Rivaroxaban: Stop 1 day before surgery 4
• For moderate renal impairment, extend apixaban discontinuation to 3 days before low-moderate risk surgery 2

Minimal Bleeding Risk Procedures (minor dental, minor skin procedures):

• DOACs may be continued or discontinued on the day of the procedure if bleeding concerns exist 4

Postoperative DOAC Management

Low Bleeding Risk Surgery:

• Resume apixaban/rivaroxaban 24 hours postoperatively at usual dose, ensuring at least 6 hours have elapsed after the procedure and adequate hemostasis is established 1, 2

High Bleeding Risk Surgery:

• Resume apixaban/rivaroxaban 48-72 hours (2-3 days) after surgery 1, 3, 2
• Consider reduced dose for first 2-3 days in high thromboembolism risk patients: apixaban 2.5 mg twice daily or rivaroxaban 10 mg once daily, then advance to full dose 1, 3
• Account for postoperative bowel dysmotility after major abdominal surgery, which may affect drug absorption 1, 2

Critical DOAC Considerations

Bridging is NOT Recommended:

• Do not bridge DOACs with heparin or low-molecular-weight heparin (LMWH) perioperatively, as this increases major bleeding risk without reducing stroke or systemic embolism 2, 4

Renal Function Monitoring:

• Patients with severe chronic kidney disease can accumulate apixaban and experience catastrophic bleeding (pleural, pericardial, intracranial hemorrhage) 2
• Extended preoperative interruption is essential in patients with declining renal function 2

Avoid Premature Resumption:

• Do not resume DOACs at full therapeutic doses immediately after major surgery due to rapid onset of action and bleeding risk if hemostasis is incomplete 2

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Warfarin Management

For patients on warfarin, stop 4-5 days before surgery to allow INR normalization, and reserve therapeutic-dose bridging anticoagulation only for high thromboembolism risk patients (mechanical heart valves, recent VTE). 5, 6

Preoperative Warfarin Management

High Thromboembolism Risk Patients (mechanical heart valves, recent VTE within 1 month):

• Stop warfarin 4-5 days before surgery 5, 6
• Bridge with therapeutic-dose LMWH (100 U/kg subcutaneously every 12 hours) or unfractionated heparin (15,000 U subcutaneously every 12 hours) 5
• Discontinue LMWH/heparin 24 hours before surgery, with effect lasting until 12 hours before surgery 5
• Alternatively, admit for IV heparin (1300 U/h continuous infusion), stopped 5 hours before surgery to allow aPTT normalization 5

Moderate Thromboembolism Risk Patients:

• Stop warfarin 4-5 days before surgery 5
• Bridge with prophylactic-dose heparin (5000 U subcutaneously every 12 hours) or LMWH (3000 U every 12 hours) 5

Low Thromboembolism Risk Patients (atrial fibrillation without other high-risk features):

• Reduce warfarin dose 4-5 days before surgery to allow INR to fall to 1.3-1.5 at time of surgery 5
• No bridging required 5

Accelerated Reversal Option:

• Give vitamin K 1-2.5 mg orally 2 days before procedure to reduce off-warfarin period to 2 days, with INR normalizing at time of procedure 5

Postoperative Warfarin Management

High Thromboembolism Risk:

• Resume warfarin postoperatively when safe (typically 12-24 hours after surgery) 6
• Restart heparin or LMWH 12 hours postoperatively in prophylactic doses along with warfarin 5
• Continue combination for 4-5 days until INR returns to therapeutic range 5
• If high postoperative bleeding risk, delay heparin/LMWH for 24 hours or longer 5

Moderate/Low Thromboembolism Risk:

• Resume maintenance dose of warfarin postoperatively 5
• Supplement with low-dose heparin (5000 U) or LMWH subcutaneously every 12 hours if necessary 5

Special Warfarin Considerations

Dental Procedures:

• Apply tranexamic acid or ε-aminocaproic acid mouthwash without interrupting anticoagulant therapy 5

Major Surgery Timing:

• Stop warfarin 5 days before major surgery and restart 12-24 hours postoperatively 6

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Emergent/Urgent Surgery on Anticoagulants

For emergent surgery (<6 hours) or urgent surgery (6-24 hours) in patients on DOACs, measure DOAC levels if available and consider reversal agents (idarucizumab for dabigatran, andexanet-α or prothrombin complex concentrates for factor Xa inhibitors) when levels are elevated. 4

• Emergent/urgent surgery in DOAC patients carries bleeding rates up to 23% and thromboembolism rates up to 11% 4
• Laboratory testing to measure preoperative DOAC levels helps determine need for reversal agents 4
• For warfarin in urgent/emergency surgery, use vitamin K subcutaneously (not other routes) 5

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Common Pitfalls and Caveats

DOAC-Specific Warnings:

• Standard coagulation tests (INR, aPTT) are not useful for monitoring apixaban effect; anti-Xa activity correlates with apixaban exposure if measurement needed 2
• For rivaroxaban, measuring prothrombin time (PT) with sensitive reagents may confirm low levels before surgery (level close to control suggests low serum concentration) 3
• LMWH is not recommended for thromboprophylaxis in patients with prosthetic heart valves, per FDA warning 5

Warfarin-Specific Warnings:

• Bridging therapy with LMWH may not be very effective at preventing embolism in atrial fibrillation or mechanical heart valves and may increase bleeding risk 7
• Heparin failures have been reported in pregnant women with mechanical prosthetic valves, possibly reflecting inadequate dosing or inferior efficacy compared to warfarin 5

Timing Precision:

• The goal is to minimize time off oral anticoagulation while ensuring adequate hemostasis 7
• Postoperative factors like intestinal dysmotility after abdominal surgery affect DOAC absorption 1, 3