What Are Pulmonary Function Tests and Why Are They Done?

Pulmonary function tests (or PFTs) are also called lung function tests. If you have warning signs or risk factors for a lung disease such as COPD, pulmonary fibrosis or asthma, your healthcare provider will order spirometry, among other tests, to check how well your lungs are working.

PFTs will also be ordered to diagnose and monitor your diagnosed lung disease, guide treatment options, and check how well your lungs respond to treatments.

Types of Pulmonary Function Tests

SPIROMETRY

Measures the amount of air you can breathe out or exhale and how fast you can empty air from the lungs. Spirometry is used to diagnose lung diseases that affect the airways, like COPD or asthma.

LUNG VOLUME

Measures the volume of air in the lungs your lungs can hold. It also measures the amount of air that remains at the end after you exhale.