Overview
Definition
A common, preventable and treatable disease that is characterized by persistent respiratory symptoms and airflow limitation that is due to airway and/or alveolar abnormalities usually caused by significant exposure to noxious particles or gases.
Epidemiology
Third leading cause of death worldwide. Highly correlated with smoking.
Etiology & Risk Factors
- Tobacco smoking (most common by far)
- Alpha-1 antitrypsin deficiency (suspect in young non-smokers with basal emphysema)
- Occupational exposures / Biomass fuel smoke
Clinical Symptoms
- Chronic and progressive dyspnea
- Chronic cough
- Sputum production
- Wheezing and chest tightness
Clinical Approach
Diagnosis
- Spirometry (Gold Standard): Post-bronchodilator FEV1/FVC < 0.70 confirms persistent airflow limitation
- Chest X-ray (Hyperinflation, flattened diaphragm)
- ABG (in severe cases, shows chronic respiratory acidosis with metabolic compensation)
Management
- Smoking cessation (most important intervention to slow decline)
- Inhaled bronchodilators: LAMA (e.g., Tiotropium) and LABA (e.g., Salmeterol)
- Inhaled Corticosteroids (ICS) for frequent exacerbators
- Long-term oxygen therapy (if PaO2 < 55 mmHg or SaO2 < 88%)
- Pulmonary rehabilitation
Complications
- Acute exacerbations (often triggered by viral/bacterial infections)
- Cor Pulmonale (Right heart failure)
- Pneumothorax (rupture of a bleb)
- Lung cancer