Tests and Procedures

Pulmonary Function Testing (PFT)

Pulmonary function testing measures how well the lungs take in and release air and how well they move gases such as oxygen from the atmosphere into the body’s circulation.

Pulmonary function tests are done to:

  • Diagnose certain types of lung disease (such as asthma)
  • Find the cause of shortness of breath
  • Check lung function before surgery

PFTs are performed on all patients over five years of age at each appointment. For more information on PFTs and other types of pulmonary function tests, please use the links below.


Pulmonary Function Testing (PFT) continued

The pulmonary function technologist will teach your child a few different ways of breathing. During the test, your child will blow into a tube with force, a lot like blowing out birthday candles. After this test, a bronchodilator (a medicine that opens the small airways in the lungs) will be given either as an inhaler or nebulized solution. The breathing test will be repeated to check for any changes.

Tell your child that the test does not hurt. Explain how the test is done and answer as many questions as you can. If your child is already taking a bronchodilator (inhaler or nebulizer) try not to use it 2 hours before the PFT. This is helpful to the test but not necessary. If your child is wheezing, coughing, or in any respiratory distress, go ahead and give the medicine as prescribed. Side effects of the bronchodilator are short lived and may include trembling and fast heartbeat.

If you have questions about why your child is being tested or the results, please ask the doctor during your visit.


FeNO Niox Test

Asthma and FeNO

All exhaled breath contains a small amount of gas called nitric oxide. When the airways of a person with asthma are inflamed, the lungs produce higher than normal amounts of nitric oxide. Hence, by measuring the amount of nitric oxide in your breath as you exhale, your doctor can tell if your airways are inflamed.

The amount of nitric oxide in your breath is called “fractional exhaled nitric oxide” or FeNO.

Why measure FeNO?

The usual methods of assessing asthma, such as asking symptoms and checking lung function with breathing tests such as spirometry, only tell part of the story.

Measuring FeNO is the only convenient way to know the severity of airway inflammation. It is an important addition to breathing tests because it can give you and your healthcare provider a more complete picture of your asthma.

Most importantly, measuring FeNO can help your doctor decide which type of medication can help manage your asthma.

Control inflammation, control asthma

Asthma symptoms occur when an irritant, such as smoke or pollen, reaches the airways and causes them to become inflamed and constricted. This can cause loss of asthma control.

Asthma triggers can vary from person to person, but the most common triggers include:

  • Allergens (such as dust, pet dander, or pollen)
  • Irritants in the air (such as smoke or perfume)
  • Respiratory infections
  • Exercise
  • Weather
  • Strong emotions
  • Some foods

***Please be aware this test is not covered by all insurance companies, in which case you will be financially responsible for the $55 payment. Please feel free to contact your insurance company prior to your appointment to see if FeNO Niox testing is covered. Your insurance will ask you for a CPT code for FeNO, which is 95012.



Diffusing Capacity of the Lung Carbon Monoxide (DLCO)

DLCO measures the lungs ability to diffuse gases/exchange gases. This is an important part of lung testing, because the major function of the lungs is to allow oxygen to “diffuse” or pass into the blood from the lungs, and allow carbon dioxide to “diffuse” from the blood into the lungs.

This test is used to diagnose certain lung diseases, and to monitor the status of people with established lung disease. Repeatedly measuring the diffusing capacity can help determine whether the disease is improving or getting worse.


Exercise Challenge Test (ECT)

In an exercise challenge test, spirometry is done before and after you exercise on a treadmill or on an exercise bicycle. An exercise challenge test can see what effect exercise has on airflow.


Methacholine and Cold Air Challenge Tests

During a methacholine challenge test you inhale a small amount of methacholine mist to see if it causes asthma symptoms. During a cold air challenge test you inhale a small amount of cold air to see if it causes asthma symptoms. Your lung function is tested before and after the methacholine/cold air are given to see how much they affect your ability to breathe.



Spirometry measures how much air you exhale and how quickly. It is a specific type of pulmonary function test that evaluates a broad range of lung diseases. In a spirometry test, while you are sitting, you breathe into a mouthpiece that is connected to an instrument called a spirometer. The spirometer records the amount and the rate of air that you breathe in and out over a period of time.


Additional Tests and Procedures

While Pulmonary Function Tests are a common in-house test for our patients over five years of age, many other tests and procedures may be ordered by our providers to help diagnose and treat all patients seen at CRCCS. Please navigate the links below to learn more about the tests & procedures commonly ordered.


Allergy/Immune Testing

ImmunoCAP is a very sensitive blood test for allergies. It measures the concentration of immunoglobulin E (IgE), which is an indicator of allergic sensitization.

ImmunoCAP can test for hundreds of allergens, such as weeds, trees, pollen, mold, food, and animal dander—all with just one blood sample.

ImmunoCAP results can help our doctors determine your child’s individual allergy profile. We can then use this profile to work with you to create an individualized treatment plan. This might include medications and tips to help you reduce exposure to your child’s specific allergic triggers, including rhinitis triggers, asthma triggers, and food allergy triggers.



A broncoscopy is a procedure that allows your doctor to look inside your lungs/airways (called the bronchi and bronchioles). The airways carry air from the trachea (windpipe) to the lungs.

During a bronchoscopy, the doctor uses a slender tube with a light and camera on the end to look at the respiratory tract including larynx (voice box), trachea (windpipe), and bronchial tubes (airways)

Bronchoscopy can help find the cause of lung problems. For example, your doctor may see:

  • Signs of infection
  • Excess mucus in the airways
  • A blockage in your airway
  • Congenital or acquired airway abnormalities


Chest CT

A chest CT (computerized tomography) scan is a painless, noninvasive test. It creates precise pictures of the structures in your chest, such as your lungs.

A chest CT is a specific type of x-ray. However, a CT scan’s pictures show more detail than a standard chest x ray.

Doctors use chest CT scans to:

  • Show the size, shape, and position of your lungs and other structures in your chest.
  • Follow up on abnormal findings from standard chest x –rays.
  • Find the cause of lung symptoms, such as shortness of breath or chest pain.


Chest x-ray

A chest x-ray is a painless, noninvasive test that creates pictures of the structures inside your chest, such as your heart, lungs, and blood vessels.

This test is done to find the cause of symptoms such as shortness of breath, chest pain, chronic cough, and fever.



An echocardiogram (“echo”) is an ultrasound test that uses high frequency sound waves (non-radioactive) for viewing the heart. It is a safe and painless procedure that helps doctors assess cardiac anatomy and function, including sources of murmur, or whether breathing issues are cardiac related. A routine pediatric echo can be expected to take an hour, but special circumstances could require longer.

If a child is 4 years old or less, he / she may require sedation for the echocardiogram. A mild sleeping medication is used that is usually taken by mouth. Children older than four years generally do not require sedation in the echocardiology laboratory. If an older child needs sedation, the test may need to be performed in an operating room setting with anesthesia support.

If children are not sedated, they may eat and go about their normal activities immediately following the study, unless you are told otherwise.


Sinus CT

A sinus CT scan is a painless, noninvasive test. It uses x-rays to create detailed pictures of the air-filled spaces inside the face (sinuses).

Doctors use sinus CT scans to detect:

  • Sinus infections (sinusitis)
  • Birth defects in the sinuses
  • Infection in the bones of the sinuses
  • Injury to the face over the sinuses
  • Masses and tumors, including cancer
  • Nasal polyps
  • The cause of repeated bloody noses


Sleep Study/Polysomnogram

A sleep study is also referred to as a polysomnogram. A sleep study monitors you as you sleep and measures your sleep cycles and stages by recording:

  • Air flow in and out of the lungs during breathing
  • Blood oxygen levels
  • Body position
  • Brain waves (EEG)
  • Breathing effort and rate
  • Electrical activity of muscles
  • Eye movement
  • Heart rate

Sleep studies are done in the hospital setting and at home. For children over one year of age, they are most often done at a sleep center. At Children’s the sleep center is located at the St. Paul campus.

Electrodes will be placed on your chin, scalp, and the outer edge of your eyelids. These remain in place while you sleep. Signals from the electrodes are recorded. Monitors to record your heart rate and breathing will be attached to your chest. A specially trained health care provider will observe you while you sleep and note any changes in your breathing or heart rate. The number of times that you either stop breathing or almost stop breathing will be measured.


Sweat Chloride

The sweat test is used to test for cystic fibrosis. A sweat sample is collected using a special sweat stimulation procedure. A tiny amount of a sweat-stimulating liquid is applied to a small patch of skin on the arm or leg. An electrode is then placed over the site and a weak electrical current stimulates the area. This is a painless procedure that may create a tingling or warm sensation. After several minutes, the area is cleaned and sweat is collected for about thirty minutes, either into a plastic coil of tubing or onto a piece of gauze or filter paper. The sweat obtained is then analyzed and the amount of chloride is measured.


Throat Culture

A throat culture is a laboratory diagnostic test to find a bacterial or fungal infection in the throat. Sampling is performed by throat swab, and the sample is put in a special cup (culture) that allows infections to grow. If an infection grows, the culture is positive. The type of infection is found using a microscope, chemical tests, or both. If no infection grows, the culture is negative.

It is most often used to diagnose strep throat.


Upper Gastrointestinal Series (UGI or Barium Swallow)

This test looks at how the upper gastrointestinal system (upper digestive system) is working. The upper gastrointestinal system includes the esophagus (the tube from the mouth to the stomach), the stomach, and the first part of the small intestine.

A radiologist will give your child a liquid called barium in a bottle, a cup, or through a small feeding tube. Barium is a contrast material that makes it possible for the x-ray camera to take images of the digestive tract.

Our providers order upper GI’s to find problems in the upper gastrointestinal (GI) tract. These problems include:

  • Inflammation of the esophagus or the stomach
  • Congenital upper digestive tract and airway anomalies
  • Gastroesophageal reflux disease (GERD)


Video Swallow Study (VFS)

A video swallow study is a test used by speech-language pathologists and occupational therapists to assess and treat dysphagia (swallowing difficulty). A patient is given food or liquid in different consistencies while the radiologist takes multiple x-ray images to form a ‘video’ of the swallow process. The video helps determine the reasons the patient may be having swallowing difficulty.