Pulmonary function tests (PFTs) determine how well a patient's lungs work. The test determines how much air goes into and out of the lungs, how much air goes from the lungs into the blood stream and how well the lungs work during exercise or physical activity. There are a variety of tests that can be performed when a patient is going through pulmonary function testing.

There are many reasons your primary care doctor or Pulmonologist might refer you for a Pulmonary Function Test. If you smoke or have issues with coughing or wheezing, shortness of breath or difficulty breathing a PFT may be used to diagnose health conditions such as COPD, asthma or lung cancer. Sometimes a PFT can also be recommended as part of an annual physical or in preparation for surgery. Franciscan Health has many in hospital and outpatient settings that offer PFT.

Types of Pulmonary Function Tests

Spirometry - This test measures the how air flows through the lungs, as well as estimating the amount of air in the lungs. It also tells the medical provider how strong the lungs are and how well the patient can breathe.

Gas diffusion study - Also called lung diffusion testing. This test is used to measure health before starting an intense exercise program, among other things.

Cardiopulmonary exercise test - This test provides precise counts of the maximum O2 intake (aerobic capacity), the causes behind the sensation of shortness of breath or difficulty breathing during physical activity or exercise (dyspnea with exertion), and gives a prognosis in patients with systolic heart failure.

Six Minute Walking Test - This test measures the distance a patient can quickly walk on a flat, hard surface for six minutes. This test reflects their ability to perform daily activities.

Body plethysmography - This test determines how much air is in the lungs after taking a deep breath in. It also helps determine how much air is left in the lungs after a deep breath out.

Note: it can take several weeks to receive your test results. A follow up appointment may be needed with your Pulmonologist to discuss your results and treatment options.

Before You Test

Before the lung function test, the patient should not smoke, vape, use a bronchodilator or drink caffeine for at least four hours prior to their lung function test.

During the lung function test, the patient will go through a series of breathing exercises with a trained respiratory therapist. After the first round of testing, the patient will be given a breathing treatment or a bronchodilator. After receiving the bronchodilator, the patient will repeat the tests over again.