Should heparin infusion be continued or switched prior to CABG surgery in a patient on Clopidogrel and Aspirin?

Management of Heparin Infusion in a Patient on Clopidogrel and Aspirin Prior to CABG

Heparin infusion should be continued until CABG surgery in a patient on clopidogrel and aspirin, while clopidogrel should be discontinued at least 24 hours before urgent CABG. 1

Antiplatelet Management Before CABG

Clopidogrel Management

• For patients referred for urgent CABG who have received clopidogrel, the drug should be discontinued for at least 24 hours before surgery to reduce major bleeding risk 1
• For elective CABG, clopidogrel should ideally be discontinued 5 days before surgery 1
• If surgery cannot be delayed, more urgent surgery may be performed by experienced surgeons if the incremental bleeding risk is considered acceptable 1

Aspirin Management

• Continue aspirin therapy throughout the perioperative period 1
• Low-dose aspirin (81 mg daily) should be maintained as it reduces operative morbidity and mortality with only a modest increase in bleeding risk 1

Anticoagulant Management

Heparin Protocol

• Continue unfractionated heparin (UFH) infusion until CABG surgery 1
• For patients transitioning from other anticoagulants to UFH before CABG:
  • If on enoxaparin: discontinue 12-24 hours before CABG and switch to UFH per institutional practice 1
  • If on fondaparinux: discontinue 24 hours before CABG and switch to UFH per institutional practice 1
  • If on bivalirudin: discontinue 3 hours before CABG and switch to UFH per institutional practice 1

Special Considerations

Bleeding Risk Assessment

• Patients receiving clopidogrel within 5 days of surgery have significantly increased risk of:
  • Postoperative bleeding (1485 ml vs 780 ml chest tube drainage in first 24 hours) 2
  • Need for blood product transfusion 2
  • Re-exploration for bleeding (5.9% vs 1.2%) 2

Bridging Strategies

• For high thrombotic risk patients (recent stent placement), consider:
  • Discontinuing clopidogrel
  • Continuing aspirin
  • Maintaining UFH infusion until surgery 1, 3
• In some cases, short-acting IV glycoprotein IIb/IIIa inhibitors (eptifibatide or tirofiban) may be considered as bridging therapy, but must be discontinued 4 hours before CABG 1, 4

Post-CABG Antiplatelet Management

• Resume P2Y12 inhibitor therapy post-operatively as soon as deemed safe to complete the recommended duration of therapy 1
• Continue aspirin indefinitely 1

Important Caveats

• Surgeon experience matters: Some studies suggest that experienced surgical teams may be able to operate with acceptable bleeding risk even when clopidogrel has been given within 5 days 5
• The decision to proceed with surgery despite recent clopidogrel exposure should balance thrombotic risk against bleeding risk 1
• Some centers use prophylactic antifibrinolytic strategies to mitigate bleeding risk when operating on patients with recent clopidogrel exposure 6
• Platelet transfusion before chest closure may have beneficial effects on hemostasis in patients who received clopidogrel within 3 days of surgery 2

Remember that while guidelines recommend discontinuing clopidogrel before CABG, the clinical urgency of the situation may necessitate proceeding with surgery despite increased bleeding risk. In such cases, appropriate blood product support should be available.