Airway Diseases: Asthma, COPD, and Bronchiectasis
Airway diseases make up a large share of the HERMES adult respiratory medicine syllabus: asthma, COPD, bronchiectasis, and overlapping obstructive patterns. The exam favours physiologic reasoning, guideline-concordant diagnosis, and safe long-term management over rare zebras.
Core rules
- Spirometry must be post-bronchodilator for COPD diagnosis: FEV1/FVC <0.70 confirms persistent airflow obstruction; severity uses FEV1 % predicted (GOLD 1 ≥80%, 2 50–79%, 3 30–49%, 4 <30%).
- Asthma is characterised by variable symptoms and variable airflow limitation; objective confirmation includes reversibility (FEV1 ≥12% and ≥200 mL), peak-flow variability, or positive bronchial challenge.
- Bronchiectasis is radiologically defined by dilated airways with bronchial wall thickening; management targets exacerbations, airway clearance, and microbiological guidance.
- Smoking cessation, vaccination, inhaler technique, and adherence are disease-modifying in all obstructive airway disease.
Worked example
A 62-year-old smoker has post-bronchodilator FEV1/FVC 0.58 and FEV1 48% predicted, with two exacerbations in the past year and CAT 22. This is COPD, GOLD spirometric grade 3, group E (≥2 moderate exacerbations or ≥1 hospitalisation). Start dual bronchodilation, assess inhaler technique, offer smoking cessation, and review exacerbation history.
Traps
Using pre-bronchodilator values to diagnose COPD; labelling every wheeze as asthma; missing bronchiectasis on HRCT; over-relying on oxygen in chronic hypercapnia; and failing to check adherence before escalating therapy.