Pulmonary function tests (PFTs) are a group of breathing tests. They can show how well your lungs are working. PFTs may measure:
PFTs may be used to help diagnose lung conditions or diseases, such as:
These tests may also be done to:
Most tests will require you to breathe into a mouthpiece. The mouthpiece may be attached to a simple handheld device or be part of a larger machine. Examples of devices are a spirometer or peak flow meter. You may be asked to breathe in and out in different patterns and speeds. You will rest between tests.
Tell the technician right away if you have breathing problems, pain, or dizziness during testing.
Other tests that may be used in some situations include:
You may be asked to breathe in small amount of carbon monoxide for 1 minute to find out how much gets into your blood. This indicates how well oxygen is getting into your blood.
Rest until you feel able to leave. You may be given medication if testing has caused wheezing, coughing, and/or difficulty breathing.
Your doctor will compare the results of your tests with normal values based on your age, gender, and height, or previous test results. Your doctor will discuss the results with you and decide if further testing or treatment is needed.
American Lung Association
Family Doctor—American Academy of Family Physicians
Beyerle J. Spirometry for the primary care provider. JAAPA. 2014 Dec;27(12):28-34.
Parker M. Interpreting spirometry: the basics. Otolaryngol Clin North Am. 2014 Feb;47(1):39-53.
Pulmonary function tests. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T900274/Pulmonary-function-tests. Updated May 27, 2016. Accessed August 29, 2017.
Pulmonary function studies. EBSCO Nursing Reference Center website. Available at: http://www.ebscohost.com/nursing/products/nursing-reference-center. Updated January 1, 2015. Accessed August 6, 2015.
Last reviewed August 2017 by Michael Woods, MD FAAP
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.