Explain to your child before the test that:
- There will be no pain
- The test is meant to find out how to help them breathe better
It can be helpful to present the test as a game, where the child must blow through a horn like it’s a toy or an instrument.
Don’t give your child any medicines that will change how they breathe before they take the test. Taking medicine prior to the test could make the test less effective. Tests should not be given to children who have certain types of heart disease, or have recently suffered a collapsed lung. Don’t feed your child a heavy meal before the test.
Pulmonary (lung) function tests help your child’s doctor diagnose a lung condition, check your child’s response to treatment, and measure your child’s condition over time. There are several different kinds of pulmonary function tests. These include:
- Breathing tests measure the size of your lungs, how much air you can breathe in and out, and how fast you can breathe air out. Examples include spirometry [spy-ROM-uh-tree] and lung volume measurement.
- Oxygen level tests assess how well your lungs deliver oxygen to your child’s bloodstream. For example, pulse oximetry (also called pulse ox) uses a special light clipped to your child’s finger (or taped to a foot) to measure the oxygen in their blood.
- Exercise tests are sometimes combined with oxygen level tests. They help your child’s doctor to understand how your child’s heart and lungs respond to the stress of physical activity. They can also help the doctor figure out the severity of your child’s condition.
Some common breathing tests include:
- Spirometry to measure how much air your child inhales and exhales, as well as how quickly they do so.
- Lung volume tests to measure how much air your child’s lungs can hold.
- Pulse oximetry to measure the level of oxygen in your child’s blood.
- Lung diffusion capacity to see how well oxygen is moved into your child’s blood in the lungs.
- Blood gas tests check the gases (oxygen and carbon dioxide) in your child’s blood.
- Nitric oxide tests measure the amount of nitric oxide your child breathes out.
Pulmonary function tests have few side effects and do not cause any pain.