P.F.T

Pulmonary function tests (PFTs) are noninvasive tests that show how well the lungs are working. The tests measure lung volume, capacity, rates of flow, and gas exchange. This information can help your healthcare provider diagnose and decide the treatment of certain lung disorders.

Pulmonary function test: A test that is designed to measure how well the lungs are working. Abbreviated PFT. PFTs gauge how the lungs are expanding and contracting (when a person inhales and exhales) and measure the efficiency of the exchange of oxygen and carbon dioxide between the blood and the air within the lungs.

During the test, you'll breathe in as much air as you can. Then, you'll quickly blow out as much air as you can through a tube connected to a machine called a spirometer. The test measures two things: The most air you can breathe out after inhaling deeply.