Lung function tests are used to diagnose and help you and your healthcare providers develop a treatment plan for possible lung conditions. These recommendations are based on evidence and agreement by Alberta Respiratory Specialists that have worked together to develop these guidelines. These can help you talk with your doctor about which lung function test you may need.
When to ask for a spirometry test
If you have symptoms of:
- asthma
- chronic obstructive pulmonary disease (COPD)
- chronic cough
Ask your doctor about a
spirometry test.
Spirometry is a measure of how much and how quickly you can move air in and out of your lungs.
This test includes a basic measure of
FEV1, FVC, FEV1/FVC.
- FEV - forced expiratory volume measures how much air you can exhale during a forced breath
- FVC - forced vital capacity is the total amount of air you exhale during the FEV measurement
It may also be called “simple spirometry” or “pre- and post-bronchodilator spirometry” or “reversible bronchodilator testing.” A bronchodilator is a medicine that helps your lungs relax so you can breathe more easily.
It’s best to do this test while you have symptoms and before you start taking any lung medicines.
When to ask for a full pulmonary function test
If you have symptoms of:
- interstitial lung disease (ILD)
- long COVID
- shortness of breath (SOB) where the cause is not yet known
Ask your doctor about a
full pulmonary function test or
PFT: It may also be called a “full PFT” or “complete PFT.” This test includes these measures:
- spirometry
- lung volumes (how much air your lungs can hold
- TLC - total lung capacity is the total amount of air your lungs can hold
- RV - residual volume is the amount of air left in your lungs after you exhale
- VC - vital capacity is the total amount of air you can exhale after taking a deep breath
- diffusion capacity (measures how well your lungs can move gas from the air you breathe to your bloodstream)
- DLCO - measures how well your lungs transfer a small amount of carbon monoxide into your blood
Remember, you are an important part of your healthcare team. Be sure to ask questions if there are things you don’t understand.
