Spirometry is the most commonly used lung function test for evaluating patients with breathing symptoms such as shortness of breath, cough and wheeze. It is also useful for lung function evaluation in patients with high risk for lung disease, such as smokers, those with occupational exposures and those with family history of lung disease.
Spirometry is typically used to detect, confirm, and monitor obstructive airway diseases (eg. asthma, chronic obstructive pulmonary disease [COPD], chronic bronchitis, pulmonary fibrosis and emphysema)
If you’ve already been diagnosed with a chronic lung disorder, spirometry may be used periodically to check how well your medications are working and whether your breathing problems are under control.
Office spirometry is also useful for monitoring control of asthma. The National Asthma Education and Prevention Program advises the following frequencies for spirometry testing when caring for patients with asthma:
-At the time of initial assessment
–After treatment is initiated and when symptoms and peak flow have stabilized
-During periods of progressive or prolonged loss of asthma control
-At least every one to two years
For patients with chronic obstructive pulmonary disease (COPD), repeat spirometry is advised whenever there is a substantial increase in symptoms or decrease in exercise tolerance.
How the test is done:
A spirometry test requires you to breathe into a tube attached to a machine called a spirometer. Before you do the test, a nurse, a technician or your doctor will give you specific instructions. Listen carefully and ask questions if something is not clear. Doing the test correctly is necessary for accurate and meaningful results.
In general, you can expect the following during a spirometry test:
- You’ll likely be seated during the test.
- A clip will be placed on your nose to keep your nostrils closed.
- You will take a deep breath in then breathe out as hard and fast as you can for several seconds into the tube. It’s important that your lips create a seal around the tube, so that no air leaks out.
- You’ll need to do the test at least three times to make sure your results are relatively consistent. If there is too much variation among the three outcomes, you may need to repeat the test again. The highest value among three close test results is used as the final result.
- The entire process usually takes less than 15 minutes.
Your doctor may give you an inhaled medication to open your lungs (bronchodilator) after the initial round of tests. You’ll need to wait 15 minutes and then do another set of measurements. Your doctor then can compare the results of the two measurements to see whether the bronchodilator improved your airflow.
SUMMARY AND RECOMMENDATIONS
Spirometry is used to detect and monitor obstructive airway disease in patients with symptoms and risk factors.