Frequently Asked Questions about Pulmonary Function Testing

What is pulmonary function testing?

Pulmonary function tests (also called PFTs or lung function tests) help determine how well your lungs are functioning. The results of these tests tell your health care provider how much air your lungs can hold, how quickly you can move air into and out of your lungs and how well your lungs are able to use oxygen and get rid of carbon dioxide. The tests help your health care provider determine if you have a lung disease, help provide a measure of how significant your lung disease is, and can show how well the treatment for your lung disease is working.

How is a pulmonary function test done?

Pulmonary function testing is usually done by a specially trained respiratory therapist or technician. For most pulmonary function tests, you will be asked to wear a nose clip to make sure that no air passes through your nose during the test. You will be asked to breathe into a mouthpiece that is connected to a machine called a spirometer. The technician may encourage you to breathe deeply during parts of the test to get the best results. Following all of the technician's instructions will help provide the most accurate results.

How do I prepare for my test?

  • You should not eat a heavy meal just before this test.
  • You should not smoke for six hours before the test.
  • You should not exercise vigorously for six hours before the test.
  • On the day of the test, avoid food or drinks that have caffeine.
  • On the day of the test, wear loose clothing that does not restrict your breathing in any way.
  • If you have dentures, wear them during the test.

May I take my medication before my test?

Yes. You should take your medications as usual unless otherwise instructed.

How long does a pulmonary function test take?

If you need spirometry only, it should take only 30 minutes. If you need complete PFTs, it takes about one hour.

What does a pulmonary function test tell my health care provider?

Pulmonary function testing helps the health care provider determine if you have a lung disease, helps provide a measure of how significant your lung disease is and can show how well the treatment for your lung disease is working. PFTs are interpreted by our pulmonologist, who is specially trained in pulmonary (lung) diseases and conditions.

When should I get my first pulmonary function test?

The need for a pulmonary function test should be determined by your health care provider.

How often should a pulmonary function test be done?

Your health care provider will decide how often you will need PFTs. This will depend on your medical condition, the medications you are taking and how well your disease is being managed.

What happens to my test results?

The PFTs are interpreted by our pulmonologist, who is specially trained in pulmonary diseases and conditions. The test results and interpretation are sent to the health care provider who ordered the test for you.

Who should have a pulmonary function test?

You should have testing:

  • To evaluate shortness of breath, wheezing and/or coughing
  • To evaluate the effectiveness of treatment
  • To screen for lung diseases
  • To evaluate your condition before surgery to assess your risk of having respiratory complications after surgery
  • To assess of the progression of your lung disease

Where can I go to get my pulmonary function test?

Your health care provider will help you to decide where you should go for your tests. The pulmonary function lab at the Women’s Medicine Collaborative is open Monday through Friday and hours are flexible to accommodate your busy schedule.