What are the current recommendations for managing patients undergoing Coronary Artery Bypass Grafting (CABG)?

Current Recommendations for Managing Patients Undergoing CABG

Use the left internal mammary artery (LIMA) to bypass the LAD and a radial artery for the second most important non-LAD vessel to maximize long-term survival and reduce cardiac events. 1

Conduit Selection Strategy

The choice of bypass conduits directly impacts long-term survival and graft patency:

• The LIMA should be used to graft the LAD in all patients without contraindications to improve survival and reduce recurrent ischemic events 1
• For the second most important stenosed non-LAD vessel, use a radial artery instead of saphenous vein to improve long-term cardiac outcomes, as randomized trials demonstrate better 10-year patency and clinical outcomes 1
• Bilateral internal mammary artery (BIMA) grafting by experienced operators can be beneficial in appropriate patients to improve long-term cardiac outcomes 1
• The right IMA can be used for LAD grafting if LIMA is unusable, or in conjunction with LIMA for BIMA grafting 1

Perioperative Beta-Blocker Management

Beta-blockers are essential throughout the perioperative period to reduce mortality and atrial fibrillation:

• Administer beta-blockers for at least 24 hours before CABG to all patients without contraindications to reduce postoperative atrial fibrillation 1
• Reinstitute beta-blockers as soon as possible after CABG in all patients without contraindications 1, 2
• Prescribe beta-blockers at hospital discharge to all CABG patients without contraindications 1
• Preoperative beta-blockers in patients with LVEF >30% can reduce in-hospital mortality 1
• In patients with systolic heart failure undergoing CABG, beta-blockers reduce in-hospital mortality from 5.20% to 2.03% and 30-day mortality from 6.16% to 2.98% 3

Perioperative Monitoring

Implement comprehensive monitoring protocols to detect complications early:

Cardiac Monitoring

• Perform continuous ECG monitoring for arrhythmias for at least 48 hours after CABG, as postoperative atrial fibrillation most commonly occurs between days 2-4 1, 2
• Continuous ST-segment monitoring is reasonable intraoperatively and may be considered early postoperatively for ischemia detection 1
• Place pulmonary artery catheters in patients with cardiogenic shock before anesthesia induction 1
• Highly selective use of pulmonary artery catheters for high-risk patients (elderly, heart failure, pulmonary hypertension) may aid in managing hemodynamic instability 1

Neurological Monitoring

• Intraoperative cerebral oxygen saturation monitoring (near-infrared spectroscopy) should guide anesthetic decisions and may prevent postoperative neurocognitive dysfunction 1
• Routine processed EEG monitoring has yielded inconsistent results and is not routinely recommended 1

Echocardiographic Monitoring

• Intraoperative TEE aids real-time assessment in CABG plus valve procedures for valve function and pathology 1
• TEE in isolated CABG aids surgical decision-making for hemodynamic status, wall motion, and ventricular function assessment 1

Glycemic Control

Aggressive perioperative glucose management prevents multiple complications:

• Maintain blood glucose ≤180 mg/dL with continuous intravenous insulin to reduce deep sternal wound infections 2
• Controlling hyperglycemia prevents osmotic diuresis that contributes to intestinal hypoperfusion and hypernatremia 4, 5

Antiplatelet and Medical Therapy

Initiate and maintain evidence-based medical therapy:

• Aspirin (100-325 mg daily) should be initiated within 6 hours postoperatively and continued indefinitely to reduce mortality, MI, stroke, renal failure, and bowel infarction 4, 2
• Continue ACE inhibitors or angiotensin-receptor blockers given before CABG, though safety of preoperative initiation is uncertain 1, 2
• Continue statin therapy with target LDL <100 mg/dL and ≥30% reduction 4

Smoking Cessation

All smokers require comprehensive intervention:

• Provide in-hospital educational counseling and offer smoking cessation therapy during CABG hospitalization 1, 2
• The effectiveness of pharmacological smoking cessation therapy before discharge is uncertain 1

Psychological Support

Screen for and treat depression to improve outcomes:

• Cognitive behavioral therapy or collaborative care for clinical depression after CABG can reduce objective measures of depression 1, 2
• Depression is associated with adverse outcomes after CABG and requires attention 2

Surgical Technique Considerations

Minimize aortic manipulation to reduce stroke risk:

• Anaortic off-pump CABG (anOPCABG) reduces postoperative stroke by 78% compared to traditional on-pump CABG, particularly in high-risk stroke patients 6
• AnOPCABG also reduces mortality by 50%, renal failure by 53%, bleeding by 36%, and atrial fibrillation by 29% compared to on-pump CABG 6
• Off-pump CABG in patients with BMI extremes (<25 or >35) reduces in-hospital mortality and morbidity 7

Quality Measures

Participate in outcomes tracking:

• All cardiac surgery programs should participate in state, regional, or national clinical data registries and receive periodic risk-adjusted outcome reports 1

Common Pitfalls to Avoid

• Avoid excessive fluid removal during cardiopulmonary bypass (>30 ml/kg ultrafiltration) to prevent hypernatremia and intestinal inflammation 4, 5
• Do not discontinue beta-blockers perioperatively unless specific contraindications exist, as this increases mortality and atrial fibrillation 1, 3
• Inadequate glycemic control increases sternal wound infection risk and should be aggressively managed 2
• Avoid using saphenous vein grafts when radial artery is available for non-LAD vessels, as radial arteries have superior long-term patency 1