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Importance of a Pulmonary Function Test

A pulmonary function test helps doctors diagnose different types of respiratory issues. The test is administered to children experiencing breathing difficulties due to asthma, allergies, lung disease, or other conditions. Testing includes an array of breathing tests designed to assess lung functioning. Dr. Maria Castro, the board-certified pediatrician at StarLight Pediatrics in Holly Springs, NC, performs the pulmonary function test and can determine if it is needed for your child.

Pulmonary Function Testing 

Pulmonary function testing can include several different types of breathing tests, including spirometry, bronchodilator response test (also called post-bronchodilator), and forced oscillometry. Spirometry is the most commonly performed test, but does not always work well with children younger than age six. The skilled and caring doctor at our pediatric office in Holly Springs, NC, will ascertain which pulmonary function tests are needed.

Spirometry: The most common of lung function tests, spirometry measures the amount of air moving in and out of the lungs, as well as how fast the air is moving. During the test, your child will be breathing through a mouthpiece that is connected to a computer. A nose clip will be worn to prevent breathing through the nose. As your child breathes in and out through the mouthpiece, a computer program measures how much air is being blow out and how fast. 

Spirometry testing can take about 30 minutes to complete is usually repeated at least two times to obtain accurate results. Part of spirometry testing is measuring peak flow. To do so, kids must be able to blow out as fast and as hard as possible. Younger children sometimes are not able to perform this part of the test. Other testing options can be used to measure lung function for kids who have difficulty testing for peak flow.

Bronchodilator Response Test: Also called a post bronchodilator test, this type of test is performed to observe the level of improvement in breathing following the use of a bronchodilator medication, such as albuterol. Spirometry is used to measure lung function or breathing right before inhaling the medicine, and again about 15 minutes after using the inhaler. The results of both tests are compared to determine if the bronchodilator medication had a marked improvement on breathing. 

Forced Oscillometry: Children who are unable to breathe in deeply or blow out hard enough to perform spirometry can be tested using forced oscillometry. This simple test is much quicker than spirometry and takes just a few minutes. Similar to spirometry, kids breathe regularly through a mouthpiece while wearing a nose clip. However, there is no need to breathe in deeply or blow out as hard as possible. Forced oscillometry measures how readily air flows in and out of the lungs.

If your child is experiencing breathing difficulties, a pulmonary function test might be needed. The test aids in assessing lung function and breathing, and can reveal how well medications, such as albuterol, are working. Schedule an appointment with Dr. Castro to find out if your child needs a pulmonary function test by calling StarLight Pediatrics in Holly Springs, NC, at (919) 762-5113.

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