Spirometry

Spirometry

A physician may recommend spirometry when chronic pulmonary disease is suspected, for example:

• Asthma
• Chronic obstructive pulmonary disease (COPD)
• Chronic bronchitis
• Emphysema
• Pulmonary fibrosis

Spirometry testing is performed daily in the Fast Track section of the emergency department by experienced experts.

What is Spirometry and When Should It Be Performed?

Spirometry is a common test used to diagnose asthma, chronic obstructive pulmonary disease (COPD), and other conditions in which the respiratory system is affected. It is also performed periodically to evaluate the function of lungs that are being treated for a chronic pulmonary condition.

Spirometry measures the amount of air you can inhale and exhale, as well as the speed of inhalation. If the values shown by spirometry are below average, it indicates that the lungs are not functioning well.

Reasons for Performing the Test

An internal medicine specialist may recommend spirometry when symptoms of chronic pulmonary disease are suspected. These conditions include:

• Asthma
• Chronic obstructive pulmonary disease (COPD)
• Chronic bronchitis
• Emphysema
• Pulmonary fibrosis

If a chronic pulmonary disorder has previously been diagnosed, spirometry is used periodically to evaluate how medications are working and whether symptoms are under control.

Related Diseases

• Asthma
• Chronic obstructive pulmonary disease (COPD)
• Emphysema
• Pulmonary fibrosis

What to Expect

When you arrive for the test:

• The nurse or technician will provide specific instructions on how to perform the test. Listen carefully and make sure you fully understand all instructions. Performing the test incorrectly leads to inaccurate results.
• A nose clip is placed over the nostrils to close them.
• The nurse or technician will ask you to take a deep breath and exhale as forcefully as possible into a tube connected to the spirometer for several seconds. You may feel briefly short of breath or dizzy after the test.
• The test must be performed at least three times to ensure accurate and consistent results.
• If, after the initial test, the internal medicine specialist prescribes an inhaled medication to open the airways (a bronchodilator), you will need to wait 15 minutes and repeat the test for new measurements. This allows the physician to compare the results from the two measurements and determine whether the bronchodilator has improved airflow. Each test usually takes less than 15 minutes.

How to Prepare

Follow the physician’s instructions regarding whether to avoid inhaled respiratory medications or other drugs before the test. Other instructions include:

• Wear loose clothing that does not interfere with deep breathing.
• Avoid eating a large meal before the test, as this makes breathing more difficult.

Key Spirometry Measurements

• Forced Vital Capacity (FVC): The greatest amount of air you can exhale after taking a deep breath. A lower-than-normal FVC value indicates restricted breathing.
• Forced Expiratory Volume in one second (FEV-1): The amount of air you can exhale from your lungs in one second. This is a good way to measure the severity of breathing problems. A low FEV-1 indicates significant obstruction.