Clinical meaning
Pulmonary fibrosis involves progressive scarring (fibrosis) of lung tissue, making the lungs stiff and difficult to expand. Normal, elastic alveolar tissue is replaced by thick collagen deposits that impair gas exchange. Patients experience worsening dyspnea because the lungs cannot expand fully (restrictive disease) and oxygen cannot efficiently diffuse across thickened alveolar walls. The disease is progressive and irreversible.
Exam relevance
Risk factors: - Exposure to occupational dusts (asbestos, silica) - Certain medications (amiodarone, bleomycin, methotrexate) - Radiation therapy to the chest - Autoimmune diseases - Smoking - Age > 50 years - Family history of pulmonary fibrosis
Diagnostics: - Monitor respiratory rate, effort, and oxygen saturation - Auscultate breath sounds (listen for fine 'Velcro-like' crackles at bases) - Monitor for increasing dyspnea and exercise intolerance - Assess oxygen needs (at rest and with activity) - Monitor for clubbing of fingertips