How should anesthesia be managed for a patient with antiphospholipid antibody syndrome on warfarin scheduled for surgery, including peri‑operative anticoagulation, neuraxial block safety, and postoperative anticoagulation restart?

Anesthetic Management for Antiphospholipid Antibody Syndrome (APLA)

Preoperative Anticoagulation Management

For patients with APLA syndrome on warfarin undergoing surgery, discontinue warfarin 5 days preoperatively to achieve INR ≤1.5, initiate therapeutic-dose LMWH bridging 3 days before surgery (36 hours after last warfarin dose), and give the last LMWH dose at half the therapeutic dose 24 hours before the procedure. 1

Warfarin Discontinuation Protocol

• Stop warfarin 5-6 days before surgery to allow INR to decrease to ≤1.5 1
• Check INR the day before surgery; if INR >1.8, administer low-dose oral vitamin K (1-2.5 mg) 1
• APLA syndrome with recurrent thrombosis qualifies as high thrombotic risk requiring bridging therapy 1
• The 2024 AHA/ACC guidelines classify antiphospholipid antibodies as a high-risk indication for anticoagulation 1

LMWH Bridging Strategy

• Begin therapeutic-dose LMWH 36 hours after the last warfarin dose (typically day -3) 1
• Administer the last preoperative LMWH dose at half the therapeutic dose 24 hours before surgery 1
• This half-dose strategy reduces residual anticoagulant effect while maintaining some thromboprophylaxis 1
• Periods without anticoagulation must be kept to an absolute minimum in APLA patients 2, 3

Neuraxial Anesthesia Safety

Neuraxial anesthesia (spinal or epidural) is contraindicated in patients on therapeutic anticoagulation and should only be performed when INR ≤1.5 and LMWH has been held for at least 24 hours, with single-puncture spinal anesthesia preferred over epidural due to lower bleeding risk. 1

Specific Neuraxial Block Considerations

• Procedures with high bleeding risk (including neuraxial anesthesia) require complete interruption of anticoagulation 1
• Single-puncture spinal anesthesia is preferable to epidural in anticoagulated patients due to reduced tissue trauma 1, 4
• The catastrophic consequence of epidural hematoma in a patient undergoing spinal laminectomy makes this particularly high-risk 1
• Aspirin alone is not a contraindication to neuraxial anesthesia if no other hemostatic abnormalities exist 1, 4

Peripheral Nerve Blocks as Alternative

• Low-risk peripheral blocks (femoral, axillary, popliteal sciatic) can be performed with careful benefit-risk assessment 1, 5
• High-risk deep blocks (infraclavicular, parasacral sciatic, posterior lumbar plexus) are contraindicated on therapeutic anticoagulation 1
• All regional blocks should use ultrasound guidance by experienced operators 1

Postoperative Anticoagulation Restart

For high bleeding-risk procedures like spinal laminectomy, wait 48-72 hours before resuming full-dose LMWH bridging, restart warfarin at the usual maintenance dose on postoperative day 0 or 1, and continue LMWH until INR returns to therapeutic range. 1

Timing Based on Surgical Bleeding Risk

• Minor procedures: Resume full therapeutic-dose LMWH within 24 hours postoperatively 1
• Major/high bleeding-risk procedures (like spinal laminectomy):
  • Wait 48-72 hours before resuming full-dose LMWH 1
  • Consider intermediate or prophylactic-dose LMWH in the interim 1
  • This decision weighs thrombotic risk against catastrophic bleeding consequences 1

Warfarin Restart Protocol

• Resume warfarin at usual maintenance dose on postoperative evening or next morning 1
• Some clinicians give twice the maintenance dose initially 1
• Continue LMWH bridging until INR reaches therapeutic range (2.0-3.0 for most APLA patients, potentially 2.5-3.5 for recurrent thrombosis) 1
• The decision to use full-dose versus prophylactic-dose LMWH bridging postoperatively is team-based, weighing thrombotic versus bleeding risks 1

Critical APLA-Specific Considerations

APLA patients require more aggressive thromboprophylaxis than standard surgical patients because thrombosis can occur despite optimal prophylaxis, and any deviation from normal postoperative course should trigger evaluation for thrombotic complications. 2, 6, 3

Enhanced Monitoring Requirements

• Combine pharmacological anticoagulation with mechanical prophylaxis (sequential compression devices) 1, 2
• Monitor closely for signs of thrombosis throughout the perioperative period 2, 3
• Any unexpected fever, pain, neurological change, or cardiopulmonary symptoms should prompt immediate thrombosis workup 2, 3
• APLA patients can develop catastrophic antiphospholipid syndrome perioperatively, with multiorgan thrombosis 6, 7

Multidisciplinary Team Approach

• Involve hematology, rheumatology, surgery, and anesthesiology in preoperative planning 1, 2, 3
• Develop a clear written perioperative anticoagulation protocol before surgery 2, 8
• For neurosurgical procedures, the stroke risk is particularly elevated and requires specific protocols 7

Common Pitfalls to Avoid

• Never perform neuraxial anesthesia with INR >1.5 or within 24 hours of therapeutic LMWH 1
• Do not delay LMWH bridging in high-risk APLA patients—start 36 hours after last warfarin dose 1
• Avoid prolonged periods without anticoagulation—this is when thrombosis occurs in APLA patients 2, 3
• Do not assume standard VTE prophylaxis is adequate—APLA requires therapeutic anticoagulation resumption 6, 3
• Remember that APLA can interfere with coagulation testing, making aPTT unreliable for heparin monitoring 8