Pulmonary Function Testing

Pulmonary function testing tells you and your doctor how well your lungs and other related body systems work. Lung function testing is an essential part of diagnosing and treating lung conditions. 

Henry Ford Health provides complex physiological testing that isn’t available everywhere. In our well-equipped laboratories, we test approximately 11,000 patients per year -- one of the largest volumes in the nation. Our specialists rely on their deep experience to understand what your individual symptoms or results might mean. This can result in faster and more accurate diagnosis, so we can help you heal or manage a lung issue.

What is pulmonary function testing?

Pulmonary function testing provides information about your lungs’ function. We evaluate for:

• Abnormalities in lung volume (how much air moves in and out of your lungs)
• Narrowing or obstruction (blockage) of the bronchial tubes, part of your airways
• Any abnormalities of oxygen or carbon dioxide exchange as part of your breathing process

These measurements help physicians determine if your lung function is normal or abnormal. Test results then help narrow down the possible causes of any abnormalities. With an accurate diagnosis, your doctor can develop an appropriate treatment plan and monitor how well it’s working for you. Lung function testing:

• Is generally painless: With most tests, you will not experience discomfort. You are awake and actively participating.
• Includes specialized testing: We offer specialized testing based on the results of standard testing. Your doctors will discuss which tests you need and what the tests mean for your diagnosis or treatment. Occasionally, a test requires a blood draw (needle stick).
• May be repeated: Doctors may order further testing to better define the findings. They also may ask you to return for repeated tests to check whether your results have changed. Ongoing testing measures your individual progress as you live with a lung condition.

Who can pulmonary function testing help?

We provide pulmonary function testing for people with all types of lung conditions. We also provide lung function tests for people receiving some types of cardiology (heart) care. You may have pulmonary tests if you are receiving treatment for:

• Asthma: Spirometry and bronchoprovocation studies can confirm a diagnosis. Sometimes, your doctor may order spirometry with an inhaler medication to determine if the medication helps.
• Chronic obstructive pulmonary disease (COPD): You will have spirometry testing to check your breathing function. Your doctor may also order spirometry performed with a diffusion capacity measurement and an inhaler medication to determine if the medication can help you.
• Interstitial lung disease (ILD): You may have spirometry and diffusion capacity testing.
• Pulmonary hypertension (PH): Spirometry and diffusion capacity testing help your doctor set a baseline for your care. A six-minute walk test also provides valuable information.
• Sarcoidosis: Our specialty clinic may order one or several tests for this condition.
• Organ transplant: Candidates for heart and lung transplant are required to complete the six-minute walk test as part of the transplant evaluation.

Pulmonary function testing at Henry Ford

Our pulmonary function testing labs are conveniently located at every pulmonary clinic where we see lung patients. Often, you’ll come for testing about an hour before your scheduled appointment with a lung specialist.

If your testing requires you to exercise, a doctor is present with you. We monitor your results and ensure you do not have any problems during testing. Your doctor will discuss your test results with you, often on the same day.

Basic pulmonary function tests

Lung and heart treatments may begin with one or more of these pulmonary tests:

• Spirometry: You’ll hold a tube in your mouth. The tube is attached to a spirometer. You take a deep breath and exhale as hard and as fast as possible. We check the outgoing air for abnormalities. This test helps to diagnose diseases that may affect the lung volume and the bronchial tubes.
• Diffusion capacity: This test measures how efficiently the lungs exchange oxygen. Diseases that scar the lungs (called pulmonary fibrosis) make it harder for oxygen to cross into the blood. Many other conditions can also reduce the diffusing capacity, including COPD, heart disease, and even anemia.
• Bronchodilator reversibility testing with spirometry: This test uses a bronchodilator medication to relax the bronchial tubes. After performing a spirogram, the pulmonologist gives you an inhaler medication. After 15 to 20 minutes, you will repeat the spirometry test to check for improvements.
• Lung volume measurements: These tests determine how much total air the lungs can hold at full lung capacity, after exhaling all the air out of the lungs. For these tests, you will be seated and breathing normally:
  
  • Body plethysmography: You’ll sit in an airtight glass booth, breathing through a mouthpiece connected to the outside of the booth. The breathing instrument measures lung volume. It senses pressure and volume changes inside the booth as well as at the mouth as you breathe in and out quickly.
  • Nitrogen washout: You’ll breathe in 100 percent oxygen for several minutes. This oxygen-rich air “washes out” the nitrogen normally found in the lungs. By doing some calculations on the total nitrogen collection, we can determine the volumes of the lungs.
• Arterial blood gas (ABG) analysis: This test involves taking a needle sample of blood directly from an artery in the wrist to measure how much oxygen and carbon dioxide it contains.

Specialized pulmonary function tests

When standard pulmonary tests don’t provide enough information, you still have options. At Henry Ford’s highly specialized pulmonary testing and physiology laboratory, we also offer:

• Bronchoprovocation studies: When doctors suspect asthma, but your spirometry test results are normal, doctors may order a bronchoprovocation study. With a doctor’s supervision in a safe controlled environment, you will breathe in small but increasing amounts of a specific medication to recreate your symptoms. As you do so, doctors will look for any changes in your spirometry test that indicate you may have asthma. If the test is positive, you’ll receive inhaler medication to immediately reverse the reaction.
• Cardiopulmonary exercise testing (CPET): We offer one of the region’s most sophisticated CPET labs, with experts who ensure accurate results. CPET uses exercise to find the cause of physical or breathing limitations during activity. You’ll ride an exercise bike for 15 to 20 minutes while a 12-lead ECG (an electrocardiograph, a type of medical heart monitor) that measures your heart’s electrical activity. You’ll also wear a face mask that enables us to measure your body’s physiology, which includes how you use oxygen and carbon dioxide and how your muscles and heart function. The results tell us if your symptoms are coming from problems with the lungs, heart, circulation or muscles. Our CPET procedures meet international standards, which means you can count on their reliability.
• Oxygen dose determination studies: These tests help us determine if you need oxygen supplementation. If you do, we can learn what dosage you need at rest and during normal activity, sleep and even exercise. Then, we can write the proper prescription to allow reimbursement for oxygen therapy. Testing involves walking on a level surface indoors while we monitor your oxygen saturation and heart rate. We watch to see if your oxygen levels fall below acceptable values.
• Six-minute walk test: This study measures how far you can walk in six minutes. You’ll take the timed test on a comfortable indoor track at Henry Ford Hospital. This test:
  
  • Is required for classification for heart and lung transplants based on international guidelines
  • Helps guide treatments and research trials by specialized clinics for conditions such as interstitial lung disease (ILD), pulmonary hypertension (PH) and sarcoidosis
  • Is used by pulmonary rehabilitation to determine if treatments are improving your condition