Managing Anticoagulation in Orthopedic Surgery: An Anesthesia-Centered Protocol

Anticoagulant management has become a critical part of preoperative planning in orthopedic surgery. While medications like apixaban, warfarin, and low-molecular-weight heparin are essential for thromboprophylaxis, they introduce complex challenges for anesthesia teams. In particular, they affect the safety and timing of neuraxial and deep peripheral blocks, increase the risk of surgical bleeding, and can trigger costly last-minute cancellations. This guide translates ASRA and ESRA recommendations into a streamlined, evidence-based protocol that anesthesia providers can apply consistently across outpatient orthopedic settings.

1. Timing Guidelines for Common Anticoagulants
The timing of anticoagulant interruption and resumption is essential to minimizing both bleeding and thrombotic risk. For safe regional anesthesia:

• Aspirin: Continue perioperatively. No bridging required.
• Clopidogrel: Hold for 5 days. Resume 4 hours post-block. Bridging rarely necessary.
• Warfarin: Hold for 5 days and confirm INR < 1.4. Resume 4 hours after block. Bridge for high-risk patients.
• Apixaban/Rivaroxaban: Hold for 72 hours if CrCl ≥ 50 mL/min. Resume after 6 hours.
• Dabigatran: Hold for 96 hours if CrCl ≥ 80 mL/min. Resume after 6 hours.
• LMWH (prophylactic): Hold for 12 hours before block. Resume after 4 hours.
• LMWH (therapeutic): Hold for 24 hours. Resume 4 hours post-block.

For deep blocks (such as adductor canal, sciatic, lumbar plexus, or PENG) these timelines must be strictly observed.

2. Scheduling and Workflow Optimization
Proactive scheduling minimizes anticoagulation-related delays:

• Intake staff must collect the specific anticoagulant and last dose timing during scheduling.
• A shared spreadsheet or EMR-integrated tool should calculate the earliest safe block date based on drug pharmacokinetics and renal clearance.
• If the safe window is not met, the case should be rescheduled or flagged for provider review.

Automating this step improves efficiency and helps ensure adherence to safety protocols.

3. Point-of-Care Testing to Reduce Cancellations
For patients uncertain about medication timing or with borderline values, rapid diagnostic tools can save cases:

• INR Finger-Stick: Confirm warfarin discontinuation. Proceed if INR < 1.4.
• Anti-Xa Level: Evaluate residual apixaban or rivaroxaban in high-risk cases. Proceed if level < 0.1 IU/mL.

In clinical audits, use of point-of-care testing has reduced same-day cancellations by over 3%, preserving significant surgical revenue.

4. Regional Anesthesia Strategy
When anticoagulation is active or recently discontinued, block selection should prioritize safety:

• Use ultrasound guidance to reduce hematoma risk.
• Avoid catheter-based blocks if anticoagulation resumption is imminent.
• Single-shot peripheral blocks are often preferable for patients scheduled to restart anticoagulants within 6 to 12 hours.
• For neuraxial blocks, strict compliance with ASRA timing is mandatory.

Ultrasound guidance reduces hematoma formation risk by more than 70% and should be considered standard of care in anticoagulated patients.

5. Hemostatic Support for the Surgical Team
Anesthesia can assist in minimizing blood loss through pharmacologic and physiologic measures:

• Administer tranexamic acid (TXA) at 15 mg/kg IV or 1 g topically to reduce bleeding.
• Include epinephrine (1:200,000) in local anesthetic infiltration to slow capillary ooze.
• Manage blood pressure proactively after tourniquet release to avoid hypotension-related bleeding.

These interventions help stabilize hemostasis and support surgical efficiency.

6. Postoperative Anticoagulant Restart Protocols
Reinitiating anticoagulation safely depends on procedure type and bleeding risk:

• Aspirin: Resume evening of postoperative day 0 for low-bleed procedures; wait until day 1 for major cases.
• LMWH: Resume after 12 hours (low risk) or 24 hours (high risk).
• Apixaban: Resume after 12 to 24 hours depending on case type.
• Warfarin: Restart evening of surgery with LMWH bridging if needed.

Restart orders should be included in the anesthesia handoff or discharge instructions. PACU staff must verify either administration or prescription at discharge.

7. Quality Metrics and Clinical Targets
Well-managed anticoagulation correlates with improved outcomes and reduced cancellations. Recommended anesthesia quality indicators include:

• Block-related hematoma: < 0.2%
• Same-day cancellation due to anticoagulation: < 3%
• Postoperative transfusion rate (TKA/THA): < 2%
• Readmission for VTE: < 1%

These metrics should be reviewed quarterly in multidisciplinary meetings to support continuous improvement.

Conclusion
Effective anticoagulation management in orthopedic cases requires discipline, preoperative coordination, and clear protocols. When anesthesia providers incorporate timing guidelines, point-of-care diagnostics, and ultrasound-based block techniques, they significantly reduce surgical delays and complication rates.

For orthopedic practices seeking to enhance safety and maintain throughput, partnering with a CRNA group skilled in anticoagulation workflows offers a measurable clinical and operational advantage. Advanced Anesthesia Services provides not only experienced clinicians but also tools like decision support templates and protocol integration to help clinics operate more smoothly.