Initial Diagnostic Approach for COPD

Primary Diagnostic Tests

The European Respiratory Society recommends spirometry as the diagnostic gold standard for COPD, demonstrating persistent airflow obstruction with post-bronchodilator FEV1/FVC ratio <0.70 1, 2
A normal FEV1 effectively excludes the diagnosis, while an abnormal FEV1 (<80% predicted) with FEV1/VC ratio <70% and minimal variability strongly suggests COPD 1, 2
The American Thoracic Society suggests that chest radiograph at first presentation helps identify emphysematous bullae and exclude serious underlying diagnoses such as lung cancer 1, 2
Chest x-ray can identify hyperinflation (flattened diaphragm, increased retrosternal airspace), bullae, and signs of cor pulmonale 4

The European Respiratory Society states that chest x-ray is essential for detecting complications and coexisting diseases in moderate and severe COPD 1, 2
High-resolution CT should be considered if early COPD is suspected despite normal chest x-ray, to identify bronchial wall thickening, gas trapping, and emphysema 7

The American College of Chest Physicians recommends suspecting COPD in patients ≥40 years with persistent respiratory symptoms (dyspnea, chronic cough, sputum production) and exposure to risk factors (smoking, occupational exposures) 3
The European Respiratory Society suggests performing spirometry to confirm diagnosis and obtaining chest x-ray to exclude alternative diagnoses (lung cancer, heart failure, pneumonia) and identify complications 1, 2, 3
The American Thoracic Society recommends measuring oxygen saturation and considering arterial blood gas if severe disease suspected 3
Assessing for signs of cor pulmonale (peripheral edema, elevated JVP, loud P2) is crucial in patients with severe COPD 1, 2