Pulmonary Function Testing

Pulmonary Function Tests (also called PFTs or breathing tests) are performed to:

  • Evaluate how well your lungs and airways function
  • Diagnose certain lung diseases including asthma or Chronic Obstructive Pulmonary Disease (COPD)

PFTs specifically measure:

  • How much air your lungs can hold
  • How quickly you can move air in and out of your lungs
  • How deeply you can breathe
  • How well oxygen diffuses in and out of your lungs

PFTs give us the information we need to help diagnose and measure the severity of lung problems, recommend treatments, and follow your progress. Most insurance carriers, Medicare, and Medicaid cover the cost of your Pulmonary Function Testing.

A Plethysmograph is an airtight booth that measures small changes in pressure that occur as you breathe. The door to the booth will remain open during all but one type of PFT. 

Frequently Asked Questions about PFTs

How should I prepare?
We’ll get the best possible information from your PFT if you:

  • Wear comfortable, loose-fitting clothing
  • Avoid smoking several hours prior to your test
  • Avoid exercise several hours prior to your test
  • Avoid heavy meals before your test
  • STOP taking the following medications:
    • 4 hours before your test: Albuterol, Ventolin HFA, ProAir HFA, Proventil HFS, Xopenex.
    • 12 hours before your test: Advair, Symbicort, Serevent, Foadil, Tudorza, Dulera, and Perofomist
    • 24 hours before your test: Spiriva, Anoro, and Breo
What should I expect?

Be prepared to spend 45 – 90 minutes to complete the study. Tests are administered with you sitting inside a clear plexiglass booth called a plethysmograph. During the test, you’ll breathe into a mouthpiece while wearing a nose clip to make sure no air passes in or out of your nose.

A Plethysmograph is an airtight booth that measures small changes in pressure that occur as you breathe. The door to the booth will remain open during all but one type of PFT.

A Plethysmograph is an airtight booth that measures small changes in pressure that occur as you breathe. The door to the booth will remain open during all but one type of PFT.

Your PFT will be administered by a specially trained respiratory therapist who will tell you how best to breathe while you’re being tested. The exact procedure is different for each type of test. The accuracy of your test depends on your ability to follow the therapist’s instructions.

Some of the tests will be performed more than once to assure consistent results, which others may be repeated after you’ve inhaled a medicated spray called a bronchodilator, which expands the airways in your lungs.

Are there any risks?
The risk of injury from a PFT is very low. You’ll be monitored at all times by a respiratory therapist seated less than five feet away. You may experience some mild, temporary shortness of breath, dizziness, or lightheadedness. Tell your therapist immediately if you feel any chest pain or discomfort.