Pulmonary Testing

Pulmonary function testing is used to evaluate, diagnose, treat and monitor lung conditions, as well as providing information about how your lungs function.

A pulmonary function test can measure your breathing capacity, flows, oxygenation, gas exchange and compliance, and can also show if you respond to bronchodilators. The tests also evaluate for abnormalities in lung volume, narrowing of the bronchial tubes, which are part of your airways and any abnormalities in the way that you are breathing.

There are several different breathing tests that can be ordered, depending on your situation, and there are many different reasons your provider may need to order a pulmonary function test. Your provider may order one or more breathing tests. The test results can help diagnose obstructive and/or restrictive lung diseases. The test results also stage or quantify the severity of your lung disease, and can also be used to monitor the effects of medications that may affect lung function.

MyMichigan Health offers a variety of pulmonary function tests. They include:

• Spirometry: You will hold a tube in your mouth that’s attached to a spirometer, take in a deep breath and exhale quickly. Your exhale is assessed for abnormalities. This test helps diagnose conditions that affect the lung volume and bronchial tubes.
• Diffusion study: This test measures how the lungs exchange oxygen. Conditions that require this study may include COPD, heart disease, anemia or pulmonary fibrosis.
• Body plethysmograph: In an airtight glass booth, you’ll breath into a mouthpiece that is connected outside the booth. This measures your lung volume and senses pressure and volume changes.
• Post-bronchodilator study: This test is similar to the spirometry test, but is performed after you have used a bronchodilator inhaler, which assists in opening your airways.
• Fractional exhaled nitric oxide (FeNO) testing: This test can determine how much inflammation you have in your airways, and can help confirm an asthma diagnosis. During the test, your breath into a mouthpiece connected to a dvice that measures how much nitric oxide is in the air when you exhale.
• Broncho-provocation challenge: This test may be ordered if your spirometry test comes back normal, but your provider suspects that you may have asthma. During the test, you will breathe in small amounts of medication to re-create your asthma symptoms. As you do this, your provider will look for any changes that may indicate that you have asthma.
• Arterial blood gas draw and analysis: During this test, blood will be drawn from an artery in the wrist to measure and analyze the amount of oxygen and carbon dioxide it contains.
• 6-minute walk test: This test measures how far you can walk in six minutes.

Preparation and Testing

At the time your test is scheduled, you’ll receive pre-test instructions. A pulmonary function technician will contact you a few days prior to your test to review the instructions and answer any questions that you may have. We ask that you wear comfortable clothes to the test, and do not smoke or exercise vigorously one hour before the test. You may eat a light meal prior to the test, but please do not have any caffeine.

Depending on which test(s) you are undergoing, your test(s) may last anywhere from 15 minutes to an hour. The testing is not painful, and you will be sitting throughout the duration of the test (unless you are taking the 6-minute walk test). A pulmonary function technician will be with you to explain each test and coach you through the testing process.

Possible side effects may include fatigue, dizziness or feeling light headed. Most often, these symptoms resolve quickly.