Pulmonary Function Testing is performed in order to detect the presence or absence of lung disease, such as asthma, bronchitis and emphysema, determine the cause of shortness of breath and measure effects of occupational and environmental exposure. It can also be performed to assess the effect of medication, measure progress in disease treatment, evaluate pre and post surgery and evaluate disability or impairment.
Lung function tests measure:
- How much air you can take into your lungs. This amount is compared to that of people your age, height and sex. This allows your doctor to see whether you're in the normal range.
- How much air you can blow out of your lungs and how fast you can do it.
- How well your lungs deliver oxygen to your blood.
- How strong your breathing muscles are.
Lung function tests usually are painless and rarely cause side effects. If you take breathing medicines, your doctor may ask you to stop them for a short time before spriometry, a lung volume measurement, or a lung diffusion capacity test.
View the PFT procedure
The breathing tests most often used are:
Spirometry (spi-ROM--eh-tree):
This test measures how much air you can breathe in and out. It also measures how fast you can blow air out.
Lung Volume Measurement:
This test, in addition to spirometry, measures how much air you have left in your lungs after you breathe out completely.
Lung Diffusing Capacity:
This test measures how well oxygen passes from your lungs to your bloodstream.
How to Prepare for a Pulmonary Function Test