What are the necessary preoperative preparations for a patient undergoing Coronary Artery Bypass Grafting (CABG)?

Preoperative Preparations for CABG

Antiplatelet Management

All patients should receive aspirin 100-325 mg daily preoperatively and continue it through surgery, as this reduces operative morbidity and mortality with only modest bleeding risk. 1

P2Y12 Inhibitor Timing (Critical for Bleeding Prevention)

For elective CABG:

• Discontinue clopidogrel and ticagrelor at least 5 days before surgery 1, 2
• Discontinue prasugrel at least 7 days before surgery 1, 2
• This timing is essential because these drugs irreversibly inhibit platelets, and waiting allows new platelet generation to restore hemostasis 1

For urgent CABG:

• Discontinue clopidogrel and ticagrelor at least 24 hours before surgery to reduce major bleeding complications 1, 2
• Discontinue prasugrel at least 24 hours before urgent surgery (though 7 days is preferred if clinically feasible) 1
• Surgery performed 1-4 days after clopidogrel cessation carries increased transfusion requirements but acceptable major bleeding risk 1, 2

GP IIb/IIIa Inhibitor Management

Discontinue short-acting intravenous GP IIb/IIIa inhibitors:

• Eptifibatide or tirofiban: at least 2-4 hours before surgery 1
• Abciximab: at least 12 hours before surgery 1
• These agents directly inhibit platelet aggregation and significantly increase bleeding if not discontinued appropriately 1

Anticoagulation Management

For patients on enoxaparin:

• Discontinue 12-24 hours before surgery 3
• Transition to unfractionated heparin (UFH) during this washout period to maintain thrombotic protection while optimizing surgical hemostasis 3
• UFH is preferred perioperatively because of its shorter half-life and reversibility 3

For patients on fondaparinux:

• Discontinue 24 hours before CABG and bridge with UFH 3
• Never use fondaparinux as sole anticoagulant during surgery due to catheter thrombosis risk 1

For patients on bivalirudin:

• Discontinue 3 hours before CABG and bridge with UFH 3

Lipid Management

All patients undergoing CABG must receive statin therapy unless contraindicated. 1

• Target LDL cholesterol <100 mg/dL with at least 30% reduction from baseline 1
• Never discontinue statins before or after CABG in patients without adverse reactions, as discontinuation increases perioperative risk 1
• Statins reduce operative morbidity and mortality through pleiotropic effects beyond lipid lowering 1

Beta-Blocker Management

Administer beta blockers for at least 24 hours before CABG to all patients without contraindications. 1

• This reduces the incidence and clinical sequelae of postoperative atrial fibrillation 1
• Reinstitute beta blockers as soon as possible after surgery 1
• Prescribe beta blockers at hospital discharge to all patients without contraindications 1

Glycemic Control

Use continuous intravenous insulin to achieve and maintain early postoperative blood glucose ≤180 mg/dL while avoiding hypoglycemia. 1

• This reduces the incidence of adverse events, including deep sternal wound infection 1
• Target intraoperative glucose <140 mg/dL has uncertain effectiveness and should not be aggressively pursued 1

Critical Pitfalls to Avoid

Do not confuse antiplatelet timing with anticoagulant timing:

• Clopidogrel requires 5 days discontinuation for elective cases 1, 2
• Enoxaparin only needs 12-24 hours discontinuation 3
• Aspirin continues throughout the perioperative period 1

Do not leave patients without anticoagulation during enoxaparin washout:

• Bridge with UFH to maintain thrombotic protection 3

Do not discontinue statins perioperatively:

• This is explicitly contraindicated and increases adverse outcomes 1

For urgent CABG in patients on clopidogrel within 48 hours:

• Mortality risk is highest when clopidogrel given within 48 hours of surgery 4
• Consider delaying if clinically stable, but if urgent indications exist, proceed with appropriate blood product availability 4, 5

Hormone Therapy Contraindication

Postmenopausal hormonal therapy (estrogen/progesterone) must not be administered to women undergoing CABG. 1

• This is a Class III (Harm) recommendation with strong evidence 1