What determines medical fitness for surgery?

Determining Medical Fitness for Surgery

Medical fitness for surgery is determined by assessing age, pulmonary function, cardiovascular fitness, and nutrition/performance status, with specific testing protocols and thresholds that predict perioperative risk and outcomes. 1

Key Factors in Surgical Fitness Assessment

Age Considerations

• Perioperative morbidity increases with advancing age, requiring more careful assessment in elderly patients 1
• Age alone should not be a contraindication for procedures like lobectomy or wedge resection for stage I disease 1
• Pneumonectomy carries higher mortality risk in elderly patients and age should be factored into surgical planning 1

Pulmonary Function Assessment

• Step 1: Initial Screening

  • For lobectomy: No further testing needed if post-bronchodilator FEV1 >1.5 liters 1
  • For pneumonectomy: No further testing needed if post-bronchodilator FEV1 >2.0 liters 1
  • These thresholds apply only if there's no evidence of interstitial lung disease or unexpected dyspnea 1

• Step 2: Additional Testing for Borderline Cases

  • Full pulmonary function tests including transfer factor (TLCO) 1
  • Oxygen saturation measurement on air at rest 1
  • Quantitative isotope perfusion scan for pneumonectomy candidates 1
  • Calculate estimated postoperative FEV1 and TLCO as percentage of predicted values 1

• Step 3: Risk Stratification Based on Step 2

  • Average risk: Estimated postoperative FEV1 >40% predicted AND estimated postoperative TLCO >40% predicted AND oxygen saturation >90% on air 1
  • High risk: Estimated postoperative FEV1 <40% predicted AND estimated postoperative TLCO <40% predicted 1
  • All other combinations require exercise testing 1

• Step 4: Exercise Testing When Indicated

  • Shuttle walk test: High risk if best distance <250m or desaturation >4% 1
  • Cardiopulmonary exercise testing: Average risk if VO2 peak >15 ml/kg/min; high risk if <15 ml/kg/min 1, 2

Cardiovascular Fitness

• All surgical candidates should have preoperative ECG 1
• Echocardiogram required for patients with audible cardiac murmurs 1
• Avoid surgery within 6 weeks of myocardial infarction 1
• Cardiology consultation needed for patients with MI within 6 months 1
• Prior coronary artery bypass surgery is not a contraindication to lung resection 1
• American College of Cardiology/American Heart Association guidelines should guide cardiovascular risk assessment 1

Nutritional Status and Performance

• Weight loss ≥10% and/or WHO performance status ≥2 suggests advanced disease requiring careful staging 1
• Preoperative assessment should include body mass index and serum albumin measurement 1
• Low nutritional values indicate increased risk of postoperative complications 1

Cardiorespiratory Fitness and Surgical Outcomes

• Cardiorespiratory fitness is a major modifiable risk factor for surgical outcomes 2
• Impaired cardiorespiratory fitness independently predicts mortality and morbidity 2
• Cardiopulmonary exercise testing provides objective metrics to assess a patient's ability to tolerate physiological stress 2, 3

Multidisciplinary Approach

• Patients with multiple risk factors but anatomically suitable for resection should be discussed in a multidisciplinary meeting involving chest physician, surgeon, and oncologist 1
• Formal liaison between referring chest physician and thoracic surgical team is essential in borderline cases 1

Preoperative Imaging and Diagnosis

• All surgical candidates should have chest radiograph and CT scan of thorax including liver and adrenal glands 1
• Diagnostic percutaneous needle biopsy may not be mandatory for peripheral lesions in otherwise fit patients 1

Risk Scoring Systems

• Objective scoring systems can help predict surgical outcomes 4
• The concept of "fitness" is evolving, with many traditional high-risk criteria no longer valid 5
• For elderly patients, overall "frailty" and geriatric risk factors (cognitive, functional, social, nutritional status) should be considered 5

Prehabilitation

• Exercise interventions before surgery can improve physical fitness and potentially surgical outcomes 3
• Supervised exercise programs with clear intensity guidelines and progression monitoring show better adherence 1
• Prehabilitation may be particularly valuable for patients with borderline fitness 3