Definition
- Pulmonary function tests (PFTs) assess lung function under three categories: ventilation, gas exchange, and pulmonary circulation.
- The FEV1/FVC ratio, normally 0.75 to 0.80, is the single most sensitive index of airway obstruction.
Classification of PFTs
Classification of pulmonary function tests
Category
Tests of ventilation
- Tests included
- Lung volumes and capacities; mechanics of breathing (FEV1, MMEFR, MVV, PEFR)
Tests of gas exchange
- Tests included
- Ventilation-perfusion matching; diffusing capacity; arterial blood gases
Tests of pulmonary circulation
- Tests included
- Pulmonary vascular pressure and blood flow