What is spirometry?
Spirometry is a simple breathing test that measures the flow and volume of air entering and leaving the lungs to find out how well your lungs are working. This is tested using a device called a spirometer.
Why would I need a spirometry test?
Spirometry can be used to diagnose asthma, chronic obstructive pulmonary disease (COPD) and other respiratory conditions. You may be referred for a spirometry test if you have signs or symptoms of a lung condition or before surgery or for other screening reasons. It is recommended as the ‘gold standard‘ test to confirm a diagnosis of chronic obstructive pulmonary disease (COPD) and to assess its severity.
What happens during a spirometry test?
The test involves taking a full breath in and blowing out as hard and as fast as you can into a tube attached to the spirometer device. The test will be done at least three times and can take from 10 to 20 minutes to complete. A clip may be placed on your nose to make sure that no air escapes from it during the test.
The spirometry test may be repeated to assess if your lung function improves after taking a reliever inhaler such as Salbutamol (Respigen, Ventolin, Salair).
How do I prepare for a spirometry test?
Your health professional should inform you on how to best prepare for the test. This may include information on which inhalers to withhold and for how long before the spirometry test. It is always a good idea to bring any inhalers you are using to the appointment. You may be asked to avoid certain activities before the test that could affect the results, such as drinking alcohol, caffeinated drinks, eating a large meal, smoking or doing strenuous exercise. Wear comfortable clothes, and it is best to go to the toilet before your test.
Is spirometry the same as peak flow?
No, these are different tests. A peak flow meter measures the peak speed at which you can blow the air out of the lungs, whereas spirometry is a diagnostic tool used to measure a range of factors to diagnose and monitor lung conditions. Peak flow meters are useful for people with asthma to manage their condition.
Are there any risks in having a spirometry test?
Spirometry is generally a safe test, however blowing out hard can put pressure on your chest, stomach, eyes and ears. You may feel dizzy at the end of the test. You might be advised against having this test if you have had a recent heart attack, stroke or experienced a collapsed lung, or if you have recently had eye, head or abdominal surgery, or a burst ear drum. Let the health professional doing the test know if you have recently coughed up blood and are unsure of the cause.
What do the results show?
Spirometry will produce a range of lung measurements which your health professional will interpret for you. Your health practitioner will need to look at your health history and your current symptoms and may recommend further testing like a CT scan. A ‘normal’ spirometry result does not necessarily rule out a lung condition, and your health practitioner will look at other factors when considering a diagnosis.
How do I get a spirometry test?
Ask your healthcare practitioner about where you can get a spirometry test. Some primary care practices and asthma societies offer this service, or you may need to be referred to your local hospital for the test by your primary care practice.