Impedance Probe Test in Children

An impedance probe test is a procedure to measure the amount of acid in the tube that connects the mouth to the stomach (esophagus). The test shows the levels of stomach acids and liquids in your child’s esophagus over a 24-hour period. This helps to diagnose gastroesophageal reflux disease (GERD). The test may also be called esophageal impedance pH monitoring or 24-hour esophageal pH test.

Your child may need an impedance probe test if he or she has symptoms of GERD, including:

• Burning pain in the chest or abdomen.
• Trouble swallowing.
• Sore throat.
• Long-lasting (chronic) cough.
• Chest tightness, shortness of breath, or wheezing.
• An upset or bloated stomach.
• Bleeding.
• Weight loss.
• Bad breath.
• Ear pain.
• Teeth that are not healthy.

Your child’s health care provider may order an impedance probe test if medicines and lifestyle changes have not eased your child’s symptoms.

What is being tested?

• Your child will be given one or more of the following:
  • A medicine to help him or her relax (sedative).
  • A medicine to numb your child’s nose and throat (local anesthetic).
• A long, thin tube will be put into your child’s nostril, down the throat, and into the esophagus. The tube has a small probe attached to one end and a monitor attached to the other end. This tube will be taped to your child’s cheek.
• This tube will stay in place for 24 hours. It measures the acid in your child’s esophagus while your child eats, drinks, sleeps, and plays as normal.
• Your child may stay in the hospital for monitoring during this test. Or, your child may be able to go home and return in 24 hours to have the tube removed. If your child can go home during the test, ask your child’s health care provider what activities are safe for your child.
• During the test, you may be asked to write down:
  • What your child eats and drinks, and how much.
  • The times of day that your child eats and drinks.
  • Any symptoms of reflux that your child has.

How do I prepare for this test?

• Follow instructions from your child’s health care provider about how to prepare for this test. Ask whether there are any eating or drinking restrictions.
• Give your child over-the-counter and prescription medicines only as told by your child’s health care provider.
• Do not give your child aspirin because of the association with Reye syndrome.
• Use a simple explanation to let your child know what to expect. Let your child know that:
  • The tube may be uncomfortable.
  • He or she might gag when the tube is inserted.

What do the results mean?

The results of this test show:

• How much stomach acid is in your child’s esophagus.
• Whether a level of acid that is higher than normal could be causing your child’s symptoms.

Your child’s health care provider will explain what the test results mean for your child. A level of acid in the esophagus that is higher than normal can mean that your child may have:

• GERD.
• Barrett esophagus.
• Inflammation of the esophagus (esophagitis).
• Abnormalities in muscle tone in the bottom of the esophagus.

It is up to you to get your child’s test results. Ask your child’s health care provider, or the department performing the test, when the results will be ready.

Talk with your child’s health care provider to discuss the results, treatment options, and if necessary, the need for more tests. Talk with your child’s health care provider if you have any questions about the results.