Cardiopulmonary Pre‑operative Assessment Guidelines

Cardiac Clearance (ACC/AHA 2014)

• Apply the 2014 ACC/AHA six‑step algorithm combined with a three‑step pulmonary protocol to determine surgical candidacy and optimize peri‑operative risk. 1
• Emergency surgery proceeds directly to the operating room with appropriate intra‑operative monitoring; formal cardiac clearance is not performed. Urgent or elective cases must follow the full algorithm. 1
• Screen for acute coronary syndrome (ACS) by evaluating for unstable angina, recent myocardial infarction (< 6 weeks), or active ischemic symptoms. Presence of ACS mandates immediate cardiology referral and management according to STEMI/NSTEMI guidelines before any elective operation. 1, 2, 3
• Estimate peri‑operative major adverse cardiac event (MACE) risk using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) risk calculator (preferred) or the Revised Cardiac Risk Index (RCRI) together with the surgical risk category. 1
• Surgical risk categories (based on expected MACE incidence):
  
  • Low risk < 1 % (e.g., endoscopic, cataract, breast, superficial procedures)
  • Intermediate risk 1‑5 % (e.g., intraperitoneal/intrathoracic, carotid endarterectomy, orthopedic, head‑and‑neck surgery)
  • High risk > 5 % (e.g., aortic/major vascular surgery, emergency surgery in the elderly, prolonged procedures with large fluid shifts)
  • Action: MACE < 1 % → proceed without further cardiac testing; MACE ≥ 1 % → assess functional capacity. 1
• Functional capacity assessment using the Duke Activity Status Index (DASI) or the ability to climb two flights of stairs; a capacity of ≥ 4 METs (activities such as stair climbing, short‑distance running, heavy housework, moderate recreation, or walking 6.4 km/h) allows proceeding to surgery without additional cardiac testing. Capacity < 4 METs or unknown capacity triggers consideration of stress testing. 1
• Stress testing is indicated only when the result could (1) change the decision to proceed with surgery or (2) influence the decision to pursue coronary revascularization. Pharmacologic stress testing is preferred for patients with poor functional capacity; exercise stress testing may be used when capacity is unknown. Abnormal results should prompt coronary angiography. If neither condition is met, surgery proceeds without stress testing. 1
• 12‑lead ECG is required for patients with known coronary disease, significant arrhythmias, peripheral arterial disease, cerebrovascular disease, or structural heart disease (except low‑risk surgery). Consider ECG in asymptomatic diabetics or those with recent chest pain undergoing intermediate/high‑risk procedures. 1
• Echocardiography is required for current or decompensated heart failure; consider it for a history of heart failure, unexplained dyspnea, or a new cardiac murmur. 1
• Special cardiac considerations (Thorax 2001):
  
  • Recent MI < 6 weeks → surgery should normally be postponed.
  • MI within 6 months → obtain cardiology consultation.
  • Prior coronary artery bypass grafting does not preclude surgery; assess these patients as any other cardiac‑risk individual. 2, 3

Pulmonary Clearance (Thorax 2001)

• Initial spirometry thresholds for proceeding without further testing:
  
  • Lobectomy → post‑bronchodilator FEV₁ > 1.5 L.
  • Pneumonectomy → post‑bronchodilator FEV₁ > 2.0 L.
  • Both require absence of interstitial lung disease or unexpected dyspnea. 3
• If spirometry is inadequate, perform full pulmonary function testing including transfer factor (TLCO), resting room‑air oxygen saturation, and a quantitative isotope perfusion scan for pneumonectomy candidates. 2, 3
• Estimated postoperative (epo) values:
  
  • For pneumonectomy, calculate epo FEV₁ and epo TLCO using perfusion‑scan data.
  • For lobectomy, use an anatomical equation subtracting the number of resected segments from the total of 19 lung segments.
  • Express epo FEV₁ and epo TLCO as percent of predicted values. 2, 3, 4
• Risk stratification based on epo predictions:
  
  • Average risk – epo FEV₁ > 40 % predicted and epo TLCO > 40 % predicted and resting O₂ saturation > 90 % → proceed to surgery.
  • High risk – epo FEV₁ < 40 % predicted and epo TLCO < 40 % predicted → advance to exercise testing.
  • Uncertain risk (any other combination) → also advance to exercise testing. 2, 3, 4
• Exercise testing for borderline cases:
  
  • Shuttle walk test (performed twice, best distance used):
    
    • < 25 shuttles (≈250 m) → high risk; surgery may be contraindicated.
    • ≥ 25 shuttles without significant desaturation → proceed to formal cardiopulmonary exercise testing (CPET).
  • Cardiopulmonary exercise testing (CPET):
    
    • VO₂ peak > 15 mL·kg⁻¹·min⁻¹ → average risk; proceed to surgery.
    • VO₂ peak < 15 mL·kg⁻¹·min⁻¹ → high risk; consider alternative treatments or accept elevated surgical mortality. 2, 3, 4

Additional Patient‑Related Risk Factors (Thorax 2001)

• Nutritional and performance status:
  
  • Pre‑operative weight loss > 10 % → high risk; requires multidisciplinary discussion.
  • WHO performance status ≥ 2 → high risk; warrants careful staging.
  • Low body‑mass index or serum albumin → increased risk of postoperative complications. 2, 3
• Age considerations:
  
  • Age > 70 years is not a contraindication to lobectomy or wedge resection.
  • Age > 80 years increases risk for pneumonectomy; age should be incorporated into the decision‑making process. 3
• Multiple adverse factors: Presence of more than one adverse medical factor (e.g., cardiac disease plus poor pulmonary reserve) mandates formal multidisciplinary team discussion involving surgeon, pulmonologist, anesthesiologist, and oncologist. 2, 3

Key Pitfalls to Avoid (ACC/AHA 2014 & Thorax 2001)

• Do not order stress testing in patients with low cardiac risk (MACE < 1 %); it does not alter management and may lead to unnecessary interventions. 1
• Avoid reliance on subjective functional‑capacity assessments; use validated tools such as DASI or objective stair‑climbing tests. 1
• Do not proceed with elective surgery in patients with active cardiac conditions (unstable angina, decompensated heart failure, severe valvular disease) without cardiology optimization. 1
• Do not assume adequate pulmonary function based solely on spirometry when interstitial lung disease is present; further testing is required. 2, 3

Preoperative Cardiac and Pulmonary Evaluation for Surgery Clearance

Cardiac History and Risk Factors

• The American College of Cardiology recommends documenting the presence or absence of active cardiac conditions such as unstable angina, recent myocardial infarction, decompensated heart failure, significant arrhythmias, and severe valvular disease, as these are absolute contraindications to elective surgery 5, 6
• Patients with prior myocardial infarction should have the timing documented, especially if within 6 months 7, 8, 9, 10
• The American College of Cardiology suggests documenting coronary revascularization, including prior CABG or PCI with stent placement 5, 7, 8, 9, 10
• Heart failure patients should have their NYHA class, recent decompensation, or changes in symptoms documented 5, 6
• The presence of pacemaker or ICD should be noted 5
• Valvular disease, including known stenosis or regurgitation, especially if symptomatic, should be documented 5, 6
• Functional capacity, including the ability to climb 2 flights of stairs or perform 4 METs of activity, should be assessed 6

Pulmonary History and Risk Factors

• The American Thoracic Society recommends documenting chronic lung disease, including COPD, asthma, and obstructive sleep apnea, as these are significant risk factors for postoperative pulmonary complications 11
• Interstitial lung disease should be documented, as it affects surgical candidacy even with adequate spirometry 7, 8, 9, 10
• Dyspnea, including progressive exertional dyspnea, exercise intolerance, or unexpected disability with shortness of breath, should be assessed 7, 8, 9, 10
• Smoking history, including current or former use, should be documented 5
• Recent pulmonary infections or exacerbations should be noted 11

Pulmonary Function and Physical Examination

• Baseline pulmonary function, including post-bronchodilator FEV1 values and transfer factor, should be documented if available 7, 8, 9, 10, 11
• Oxygen saturation at rest and on room air should be measured 7, 8, 9, 10, 11
• Respiratory rate and pattern, including signs of respiratory distress, should be assessed 11

Additional Risk Factors and Communication

• Age ≥65 years significantly increases pulmonary complication risk 11
• Functional dependence, including inability to perform activities of daily living, should be documented 11
• Weight loss >10% preoperative weight loss indicates high risk 7, 8, 9, 10, 11
• Nutritional status, including body mass index and serum albumin, should be assessed 7, 8, 9, 10, 11
• Performance status, including WHO performance status ≥2, indicates need for careful assessment 7, 8, 9, 10
• The American College of Cardiology recommends avoiding the phrase "cleared for surgery" and instead documenting cardiovascular stability, optimal medical condition, and specific recommendations for medication changes or additional testing 5, 6