What are the postoperative care guidelines for an adult patient with a history of coronary artery disease, hypertension, and diabetes after undergoing Coronary Artery Bypass Grafting (CABG) surgery?

Postoperative CABG Care Guidelines

All CABG patients should receive aspirin (100-325 mg daily) within 6 hours postoperatively, beta-blockers at discharge, and statin therapy indefinitely, with aggressive glycemic control targeting ≤180 mg/dL using continuous IV insulin to reduce mortality, infection, and graft failure. 1, 2

Immediate Postoperative Management (First 48 Hours)

Cardiovascular Monitoring and Medications

• Continuous ECG monitoring for at least 48 hours is mandatory to detect arrhythmias, particularly atrial fibrillation which occurs commonly and increases stroke risk 1, 3
• Initiate aspirin 100-325 mg within 6 hours of surgery and continue indefinitely as the standard of care for preventing early saphenous vein graft closure, reducing mortality, MI, stroke, renal failure, and bowel infarction 1, 2
• Administer beta-blockers preoperatively or early postoperatively to all patients without contraindications (particularly those with LVEF >30%) to reduce atrial fibrillation incidence, clinical sequelae, and in-hospital mortality 1
• Consider prophylactic amiodarone preoperatively for high-risk patients to reduce postcardiotomy atrial fibrillation 1

Glycemic Control

• Maintain blood glucose ≤180 mg/dL using continuous IV insulin infusion to aggressively control perioperative hyperglycemia, which reduces deep sternal wound infection risk, prevents osmotic diuresis leading to intestinal and hepatic hypoperfusion, and decreases overall adverse events 1, 2, 3
• Avoid hypoglycemia while maintaining tight control 3

Hemodynamic Management

• Maintain mean arterial pressure >60 mm Hg in patients with preexisting dysfunction to ensure adequate organ perfusion, particularly hepatic and intestinal 3
• Avoid excessive fluid removal during cardiopulmonary bypass and postoperatively, as hyperosmotic dehydration contributes to intestinal inflammation and hepatic injury 2, 3
• Place pulmonary artery catheter in patients with cardiogenic shock before anesthesia induction; consider for acute hemodynamic instability 1

Infection Prevention

• Preoperative antibiotic administration is mandatory in all patients to reduce postoperative infection risk 1
• Aggressive glycemic control with continuous IV insulin (target ≤180 mg/dL) significantly reduces deep sternal wound infection risk 1
• If deep sternal wound infection develops, treat with aggressive surgical debridement and early revascularized muscle flap coverage 1

Anesthetic and Ventilation Strategy

Fast-Track Management

• Anesthetic management should be directed toward early postoperative extubation and accelerated recovery in low- to medium-risk patients undergoing uncomplicated CABG 1
• Use volatile halogenated anesthetics with opioid supplementation rather than high-dose opioid regimens 1
• Employ nondepolarizing neuromuscular-blocking agents with intermediate duration (avoid pancuronium which delays extubation) 1

Secondary Prevention at Hospital Discharge

Mandatory Medications

• Beta-blockers must be prescribed at discharge to all patients without contraindications 1
• Continue statin therapy indefinitely with target LDL <100 mg/dL and at least 30% reduction from baseline; discontinuation increases mortality 2, 3, 4
• ACE inhibitors or angiotensin-receptor blockers are recommended before CABG and should be continued, though safety of preoperative administration in chronic users requires caution due to potential hypotension 1

Antiplatelet Therapy

• Aspirin remains the drug of choice and should be continued indefinitely given its benefit in preventing subsequent clinical events and maintaining graft patency 1, 4
• Clopidogrel should be withheld for 5 days before CABG if clinical circumstances permit 1

Smoking Cessation

• All smokers must receive in-hospital educational counseling and be offered smoking cessation therapy during CABG hospitalization 1
• Offer pharmacological therapy including nicotine replacement and bupropion to patients willing to quit 1
• Active smoking independently predicts future coronary events (HR 1.51) after CABG 5

Risk Factor Management and Rehabilitation

Diabetes Management

• Diabetes independently predicts long-term coronary events (HR 1.61) and requires aggressive control 5
• Continue tight glycemic control after discharge 2

Lipid Management

• Hyperlipidemia independently predicts future coronary events (HR 2.13) after CABG 5
• These risk factors display progressive stepwise increment in risk when cumulatively present 5

Cardiac Rehabilitation

• Initiate cardiac rehabilitation as an essential component of postoperative care 4
• Early patient mobilization should be a goal alongside early extubation and hospital discharge 1

Special Considerations for High-Risk Patients

Right Ventricular Involvement

• After infarction leading to clinically significant right ventricular dysfunction, delay surgery for 4 weeks to allow recovery 1
• Provide specialized myocardial protection for inferior infarct with right ventricular involvement 1

Concomitant Valve Disease

• Patients with severe aortic stenosis (mean gradient ≥50 mm Hg or Doppler velocity ≥4 m/s) meeting valve replacement criteria should have concomitant aortic valve replacement 1
• Clinically significant mitral regurgitation should receive concomitant mitral correction at time of CABG 1

Monitoring for Complications

Arrhythmia Surveillance

• Continue ECG monitoring for at least 48 hours; consider ST-segment monitoring intraoperatively for ischemia detection 1
• Atrial fibrillation increases postoperative stroke risk and requires aggressive prevention and treatment 1

Organ Dysfunction Monitoring

• Monitor for postoperative renal dysfunction, which carries high mortality when combined with hepatic dysfunction 1, 3
• Watch for signs of intestinal inflammation or bowel infarction (aspirin within 48 hours reduces this risk) 2, 6
• Monitor hemodynamic parameters including cardiac output, mixed venous oxygen saturation, and lactate in high-risk patients 3

Neurologic Assessment

• Reduce stroke risk by minimizing cardiopulmonary bypass time, managing aortic atherosclerosis, and preventing/treating atrial fibrillation 1
• Consider epiaortic ultrasound imaging to reduce stroke rates 1

Common Pitfalls to Avoid

• Do not discontinue statins unless active liver disease develops, as this increases mortality 3
• Avoid aggressive ultrafiltration or excessive diuresis causing hyperosmotic dehydration, which leads to intestinal and hepatic complications 2, 3
• Do not delay aspirin administration beyond 6 hours postoperatively, as early administration (within 48 hours) significantly reduces multiple complications 2
• Older patients and those without regular cardiology follow-up have lower rates of appropriate medication use; ensure discharge prescriptions are complete 7
• Patients who continue smoking are less likely to adhere to prescribed medications and have worse outcomes 7, 5