Pulmonology
Core concepts
Build a structured approach to dyspnoea: obstructive (asthma, COPD), restrictive (ILD, neuromuscular), vascular (PE), and parenchymal (pneumonia, oedema). Understand spirometry interpretation - post-bronchodilator FEV1/FVC <0.70 defines obstruction; a reduced FVC with preserved ratio suggests restriction, confirmed by lung volumes. Know asthma control assessment and stepwise therapy, COPD exacerbation management (bronchodilators, steroids, antibiotics when indicated, controlled oxygen, NIV for acidosis), and the Wells/PERC pathway for PE.
Traps
Questions test oxygen targets: 88–92% in COPD at risk of hypercapnia, versus 94–98% generally. Distinguish asthma (reversible, diurnal, atopic) from COPD (fixed, smoking, air trapping). A normal chest radiograph does not exclude PE or early pneumonia. In pleural effusion, Light's criteria separate exudate from transudate; do not assume all effusions in heart failure are transudates. Sarcoidosis and TB both cause hilar adenopathy - look at the clinical context and laterality.
Rule of thumb
For a COPD exacerbation with respiratory acidosis (pH <7.35, raised PaCO2), non-invasive ventilation reduces mortality and intubation - start it early rather than waiting for deterioration.
Worked example
A 30-year-old with sudden pleuritic pain, tachycardia, and hypoxia after a long flight: calculate Wells, send D-dimer if low/intermediate probability, and proceed to CT pulmonary angiography if high probability.