Perioperative Anticoagulant Management

Perioperative management balances the bleeding risk of the procedure against the clot risk of stopping anticoagulation. Classify the procedure, check kidney function, choose a stop and restart schedule for the specific drug, and decide on bridging for warfarin only in high-risk patients.

Procedure risk. Low bleeding risk: dental extraction, cataract surgery, skin surgery, minor endoscopy without biopsy, pacemaker insertion. High bleeding risk: major abdominal, orthopaedic, cardiac, vascular and neurosurgery, urological surgery, polypectomy, neuraxial anaesthesia and procedures with a high chance of haemorrhage.

Direct oral anticoagulants (no bridging):

• Apixaban, rivaroxaban, edoxaban with creatinine clearance 50 mL/min or more: low bleeding risk, omit for 1 day before (last dose 2 days before); high bleeding risk, omit for 2 days before (last dose 3 days before).
• Dabigatran with creatinine clearance 50 mL/min or more: low risk 1 day, high risk 2 days; clearance 30 to 49 mL/min: low risk 2 days, high risk 4 days.
• Restart 24 hours after low-risk procedures and 48 to 72 hours after high-risk procedures when haemostasis is secure.

Use prophylactic low molecular weight heparin meanwhile if the patient is high risk for clots and restart is delayed.

Warfarin: - Stop 5 days before major procedures, check INR the day before (give oral vitamin K 1 to 2 mg if over 1.5), and restart the evening of surgery or the next day. Bridge only for mechanical mitral valves, mechanical aortic valves with risk factors, thrombosis or stroke within 3 months, and severe thrombophilia. - Minor procedures (dental extraction, cataract, skin surgery): continue warfarin if INR is under 3.0 on the day, with local haemostatic measures; tranexamic acid 5% mouthwash 10 mL four times daily for 2 days after dental extraction.

Antiplatelet drugs. Continue aspirin 75 to 100 mg in most surgeries. Do not stop dual antiplatelet therapy within 1 month of a bare-metal stent or 6 months of a drug-eluting stent without cardiology advice.

Neuraxial anaesthesia. Last dose of low molecular weight heparin at least 12 hours (prophylactic) or 24 hours (therapeutic) before puncture; direct oral anticoagulants at least 72 hours; warfarin with INR 1.4 or under.

Emergency surgery. Reverse the anticoagulant: vitamin K 5 to 10 mg intravenously with prothrombin complex concentrate 25 to 50 units/kg for warfarin; idarucizumab 5 g intravenously for dabigatran; andexanet alfa or prothrombin complex concentrate 50 units/kg for factor Xa inhibitors.

Kidney impairment. Longer holds for dabigatran and for low molecular weight heparin.

Older adults. Frail patients with falls risk need earlier review of benefit.

Special groups. Pregnant women having caesarean section need heparin timing set by the obstetric anaesthetist. In East Africa, INR availability on the day of surgery and limited reversal agents favour planned elective timing.

Monitoring. INR on the day before warfarin-related surgery, creatinine before direct oral anticoagulant stops, and bleeding checks at the wound and drains for 48 hours.

Referral and escalation. Seek haematology review for mechanical valves, recent stroke or thrombosis, antiphospholipid syndrome, and any procedure with a high bleeding risk on dual therapy.

Stopping. Document the stop date, the restart date and the restart drug and dose in the discharge summary.