Frequently Asked Questions About Spirometry Tests

Your doctor will generally do a spirometry test if you're having respiratory problems, either to diagnose or rule out a lung condition. Certain factors raise your risk of a respiratory condition and may make your doctor more likely to run this test; people over 35 who are regular smokers, and those with persistent coughs fall into this category.

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Spirometry can help doctors diagnose various respiratory conditions including asthma, COPD, cystic fibrosis, and pulmonary fibrosis. Asthma and COPD are both conditions in which the airways narrow. However, in the case of asthma, they can also inflame. Cystic fibrosis is a genetic condition that causes a build-up of sticky mucus in the lungs, while pulmonary fibrosis is scarring of the lungs. If your doctor has already diagnosed you with of one of these conditions, a spirometry test can help them determine how you're responding to treatment.

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People with existing lung conditions tend to receive scheduled spirometry tests. As well, smokers and former smokers, particularly those over 40, should undergo testing on a regular basis. If you smoke or have been a smoker and are experiencing breathing problems, COPD is a likely diagnosis, but your doctor can also rule it out with a spirometry test.

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Spirometry tests are incredibly important because the earlier you're tested, the earlier a condition can be detected. Many treatments can reduce the symptoms of a common lung problem and also prevent the condition from worsening, ultimately improving day-to-day life and even lifespan.

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Spirometry tests are painless, take only a couple of minutes, and can be carried out in a basic doctor's office or clinic. Your doctor will apply a nose clip and ask you to blow through a mouthpiece after taking as large a breath as possible. When breathing out, you will force the air out of the lungs until they are completely empty. Generally, you will be asked to complete the test a few times in succession.

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Your doctor will advise you to abstain from smoking for a specified amount of time before the test. You may also be asked to avoid eating or drinking for two to four hours prior, and not to do any form of exercise for at least 30 minutes before. Finally, if you have an inhaler, check with your doctor about whether or not you'll be able to take it before the test.

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Spirometry measures lung functions and can record the forced vital capacity and forced expiratory volume using your breath. Forced vital capacity (FVC) refers to the largest amount of air you can blow out in total. Forced expiratory volume (FEV1) calculates the amount of air you expel in the first second. If your forced expiratory volume is low, this could point to asthma or COPD.

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The results of a spirometry test are not usually available immediately following the exam, because the doctor or operator must review and extrapolate the results. This involves comparing your measurements to those of other patients with similar characteristics such as height, age, and sex.

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Hopefully, the results of your spirometry test will indicate to the doctor which, if any, respiratory condition you have. They can indicate whether the nature of the condition is obstructive, restrictive, or a combination of both, and this can help determine treatment. Obstructive airways disease affects your ability to breathe out quickly due to a narrowing airway, but the amount of air in the lungs is not affected. On the other hand, restrictive lung disease means your lungs are unable to expand, thus decreasing the amount of air you can breathe in.

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Spirometry is a straightforward and safe test. While some people report feeling dizzy, shaky, or faint for a short period after, most will not experience these symptoms. If you do feel dizzy or faint, don't worry. This is simply because spirometry increases the pressure inside the head, chest, and stomach. There are only a few instances where the test may not be safe to do: if you have angina, have had a heart attack or have high blood pressure, you may not be able to take the test. Also, if you have undergone an operation on the head, chest, stomach, or eyes, your doctor will likely recommend an alternate diagnostic tool.

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