Why spirometry is used

If you have questions or concerns about your lung health, talk to you doctor about spirometry. The earlier spirometry is done, the earlier lung disease can be detected and treated. There are many treatments to reduce symptoms, to prevent lung disease from becoming worse, decrease flare-ups exacerbations and improve your day-to-day life.

The entire test usually takes less than 10 minutes, although sometimes it is repeated after taking a puffer medication. You will be asked to breathe through a mouthpiece while wearing a nose clip. You'll be able to go home soon after the tests have finished and return to your normal activities.

The person carrying out the test won't usually be able to give you your results immediately. The results will need to be looked at by a specialist first and will then be sent to the doctor who referred you for the test, who will discuss them with you a few days later.

A spirometer measures the amount of air you can breathe out in one second and the total volume of air you can exhale in one forced breath. These measurements will be compared with a normal result for someone of your age, height and sex, which will help show if your lungs aren't working properly.

The measurements will also show whether any problem with your lungs is "obstructive", "restrictive", or a combination of the two:.

Spirometry is a straightforward test and is generally considered very safe. Some people may feel dizzy , faint, shaky, sick or tired for a short period afterwards. Few complications typically occur during or after a spirometry test.

However, you may want to be aware of the following. You may feel a bit dizzy or have some shortness of breath immediately after performing the test, according to the American Thoracic Society. In this case, stop immediately and tell your doctor. In very rare cases, the test may trigger severe breathing problems. When you do this test, it will increase the pressure in your head, chest, stomach, and eyes as you breath out.

There are few risks related to the spirometry test itself. However, there is a minor risk that you may get an indirect infection. This risk may be higher in different countries, where there are other standards and protocols for preventing the spread of infection. The American Thoracic Society and the European Respiratory Society have official technical standards for conducting spirometry.

These include disinfection guidelines and recommend disposable mouthpieces with filters to avoid infections. Spirometry measures two key factors: expiratory forced vital capacity FVC and forced expiratory volume in one second FEV1. One of the primary spirometry measurements is FVC, which is the greatest total amount of air you can forcefully breathe out after breathing in as deeply as possible.

If your FVC is lower than expected, something is restricting your breathing. The second key spirometry measurement is FEV1. Other preparations include the following:. A spirometer is a diagnostic device that measures the amount of air you're able to breathe in and out and the time it takes you to exhale completely after you take a deep breath. 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. 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.

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