COPD Exacerbation
Pulmonology
Illness script · Pulmonology
COPD Exacerbation
Acute worsening of COPD symptoms beyond normal day-to-day variation, typically triggered by infection or environmental irritants.
This illness script for COPD Exacerbation covers predisposing factors, classic presentation, mechanism, workup, management, and the clinical pivots that separate it from look-alikes—written for USMLE Step 1 and clerkship reasoning.
01
Predisposing factors
- Underlying COPD (FEV1/FVC <0.70 post-bronchodilator)
- Smoking history (>10 pack-years most common RF)
- Viral URI (rhinovirus most common trigger); bacterial: H. influenzae, S. pneumoniae, M. catarrhalis
- Air pollution, cold air, allergen exposure
- Prior exacerbations strongest predictor of future exacerbations
- Older age, poor baseline FEV1
02
Presentation
- Increased dyspnea, sputum production, and sputum purulence (Anthonisen criteria)
- Accessory muscle use, pursed-lip breathing, barrel chest on exam
- Diffuse expiratory wheezing and prolonged expiratory phase
- Tachypnea, tachycardia; cyanosis in severe cases
- ABG: hypoxemia ± hypercapnia with respiratory acidosis (pH <7.35, ↑PaCO2)
- Altered mental status signals impending respiratory failure
03
Pathophysiology
- Trigger → airway inflammation → mucus hypersecretion + bronchospasm
- Increased airflow obstruction → dynamic hyperinflation → air trapping
- V/Q mismatch → hypoxemia; CO2 retention → hypercapnic respiratory failure
- Respiratory muscle fatigue may precipitate acute respiratory failure
04
Diagnostics
- CXR first-line: rule out pneumonia, pneumothorax, CHF
- ABG: assess severity — hypercapnia (PaCO2 >45) indicates ventilatory failure
- Sputum culture if purulent or hospitalized
- ECG: rule out ACS, RV strain (cor pulmonale)
- Spirometry NOT performed during acute exacerbation
05
Management
- Short-acting bronchodilators (SABA + SAMA, e.g., albuterol + ipratropium) first-line
- Systemic corticosteroids (prednisone 40 mg x5 days) reduce treatment failure
- Antibiotics if ≥2 Anthonisen criteria or severe exacerbation (azithromycin or doxycycline)
- Controlled O2 therapy: titrate SpO2 to 88–92% (avoid over-oxygenation → ↑CO2)
- NIV (BiPAP) for hypercapnic respiratory failure (pH <7.35); intubate if NIV fails
06
Clinical pivots
How to separate this script from the look-alikes that show up on exams and on the wards.
Acute Decompensated Heart Failure
Bilateral crackles, S3 gallop, BNP markedly elevated, CXR shows pulmonary edema — not hyperinflation
Pneumonia
Focal consolidation on CXR and fever help distinguish; can coexist and trigger exacerbation
Pulmonary Embolism
Sudden-onset pleuritic chest pain, no wheezing, normal CXR; D-dimer/CTPA confirms
Asthma Exacerbation
Younger patient, atopy, no smoking history, fully reversible obstruction on PFTs, normal DLCO
Keep reading
Full library- Community-Acquired PneumoniaAcute lower respiratory tract infection acquired outside hospital, causing alveolar consolidation and impaired gas exchange.
- Deep Vein ThrombosisThrombus formation in a deep vein (most often proximal lower extremity) causing obstruction and risk of pulmonary embolism.
Educational use only. This illness script is a study framework, not medical advice. Confirm decisions with current guidelines and your clinical supervisors.