Skip to page contentSkip to footer

This handout is about the kidney test your child will have. You might hear it called a “Lasix Renal Scan.” Renal means kidney.

What is a Lasix® kidney (renal) scan?

This test looks at how the kidneys work and drain. The scan can find out if there is a blockage.

How do I get ready for this test?

Bring something to help your child lay still for the test. You may bring books, movies, or if young enough, a bottle to drink.

Ask your doctor if your child needs sedation to be sleepy during the test. If needed, we will call you the day before. You will be told what time your child should stop eating and drinking.

If your child does not need sedation, babies may have their normal feeding and older children may eat and drink before the test.

What should you and your child expect?

You will arrive at the American Family Children’s Hospital and check in at the Radiology Imaging Pavilion. Our staff will take you to where the test will be done.

We will explain the process to you and answer any questions you may have. One or two parents or caregivers may stay with the child during the scan.

Next, your child will have an IV started. The IV will be used to give fluids and medicine. In most cases, if your child is 10 years old or younger they will have a catheter placed into the bladder. Your doctor can tell you whether your child will need this.

A Child Life Specialist will help you and your child through these steps and the test.

How is the test done?

Your child will need to lie flat on a table for about 45 minutes. It is very important to be still during this test. The person doing the scan may need to swaddle the child to ensure a good study. A special scanning camera under the table is used to capture the image.

A series of pictures will be taken while medicines are given through the IV. The first medicine is a small amount of a radioactive substance to get pictures of the kidneys. The second medicine, Lasix® (furosemide), will be given part way through the study to help drain the kidneys.

The catheter and IV will be removed after the imaging is done. When your child is stable, you will have a follow-up visit or be able to go home. You will discuss the results of the test with your child’s doctor at a later time.

How will my child feel afterwards?

The scan is painless, except for the discomfort of having an IV and catheter placed. The Lasix® can give you an urgent need to go to the bathroom. The longer we can take pictures before you need to use the bathroom the better. The urgent need is less when a catheter is in place.

What are the risks?

Many people worry when they hear that the substance used in this test is radioactive. The amount used is so small that there should be no side effects.

Who to Call

UW Health Radiology

Monday-Friday 8:00-4:30

(608) 263- 9729

Toll free 1-800-323-8942; ask for Radiology.