Pulmonary Function Tests

Interpretation of Abnormal Pulmonary Function Test Results

Pulmonary Function Tests (PFTs) are essential diagnostic tools used to assess lung function and detect respiratory abnormalities. These tests measure various aspects of breathing and lung capacity to diagnose conditions like asthma, COPD, and restrictive lung disease.

Understanding PFT Components

• Spirometry: Evaluates airflow limitation by measuring forced vital capacity (FVC) and forced expiratory volume in one second (FEV1).
• Lung Volume Measurement: Identifies restrictive lung diseases by analyzing total lung capacity (TLC) and residual volume (RV).
• Diffusion Capacity: Assesses gas exchange efficiency through carbon monoxide diffusion testing (DLCO).

Interpreting Abnormal Results

Abnormal PFT results indicate underlying lung pathology:

• Obstructive Pattern: Reduced FEV1/FVC ratio suggests airflow obstruction seen in asthma and COPD.
• Restrictive Pattern: Decreased TLC and FVC signify conditions like pulmonary fibrosis or neuromuscular disorders.
• Impaired Diffusion: Low DLCO may indicate interstitial lung disease or pulmonary vascular conditions.

Clinical Implications

Identifying abnormal PFT results aids in early disease management, guiding treatment strategies and patient care.