Pulmonary Function Testing
Pulmonary Function Testing is a detailed look at how well you breathe.
Your healthcare provider may order this test for many reasons:
- To verify if your lungs will tolerate anesthesia if you are planning on having surgery
- To diagnose asthma or other underlying lung conditions
- To explain why you might be short of breath
- To see how smoking may have affected your lungs
Prior to testing, you may be asked to do some of the following:
- Stop smoking for 8-12 hours prior to your test
- Stop taking your breathing medication 4-12 hours prior to the test
- Avoid caffeine
- Eat only a light meal and limit fluids
- Wear loose clothing that won’t restrict your breathin
- Staff will instruct you as to which instructions apply.
During testing, you may be asked to sit in a chair or in a clear plastic box that looks similar to a phone booth. Our respiratory therapist will ask you to wear nose clips and to breathe through a mouthpiece that is connected to a computer system. A complete assessment consists of a series of 3 tests. You may be given all three or only a portion depending on what your provider orders.
The three types of tests are:
Spirometry: During this test, you will need to take a deep breath and then blow it out hard and fast. This measures the force and amount of air that leaves your lungs.
Diffusion: This test requires you to hold your breath for 10 seconds. Diffusion measures how well your lungs transfer oxygen into your blood.
Lung volumes: Our respiratory therapist will guide you through a breathing exercise and several measurements will be taken regarding the amount of air that moves through your lungs when you inhale and exhale.
You may take breaks between these tests if you become tired. A complete assessment usually lasts 45 minutes – 1 hour. After you are done with your test, you may return to your normal daily activities. Your provider will discuss your results with you at your next visit.