What is a pulmonary function test (PFT)?

Pulmonary function testing (PFT) is a general term for tests that help determine how well your lungs and airways are working. These tests require you to breathe into a machine.

One common test, spirometry, measures how much air you can breathe out and how fast. Another test, the VO2 test, measures your body's ability to use oxygen during exercise.
A platelet function test measures the rate at which your blood clots. Physicians who are treating cardiovascular patients will often order a platelet function test to see if antiplatelet medications that have been prescribed to prevent blood clots are working at their intended level. Platelet function tests can also be used to help identify the cause of excessive bleeding or to see if bleeding is a risk during surgery.
Paul M. Ehrlich, MD
Allergy & Immunology
Also known as spirometry, the pulmonary function test is usually done in the office of either an allergist or a pulmonologist. It is a more sophisticated evaluation of the lungs and is often used to make a definitive diagnosis of asthma. The test involves breathing into a machine that calculates different breathing parameters. By testing before and after giving the patient an inhaler such as albuterol, the clinician can see if there is significant improvement. Improvement may indicate reactive airways as found in asthma. The test is limited by its difficulty to perform in children less than 6 years old.
Asthma Allergies Children: A Parent's Guide

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Asthma Allergies Children: A Parent's Guide

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.