Urodynamics is a group of tests used to measure the bladder’s ability to hold urine and to study how the bladder empties. By watching the pressure in the bladder when it fills and when it empties, more can be learned about how the bladder works.

Your child will have a small catheter (tube) placed into their bladder. A numbing jelly (lidocaine jelly) is used before the catheter is placed to make the catheter placement more comfortable for your child. This is similar to the way a dentist numbs a part of your mouth when you have dental work done. A small tube is placed in the rectum to measure the pressure in the abdomen (tummy area).

The tubes are hooked up to a computer that measures bladder and abdominal pressures. The tubes will stay in place for the test, which takes about one hour. The bladder will be filled with liquid and x-ray pictures will be taken. Your child will be asked to pee out the liquid. If your child cannot do this, the bladder will be emptied when the test is over.

The following will be helpful for the test:

  1. If your child has had many bladder infections, ask your primary care provider to test the urine 7 to 10 days before your appointment. The urodynamics test should not be done if your child has a bladder infection. If your child has an infection, antibiotics can be started before the test to clear the infection.
  2. If your child is taking any medications for the bladder, such as Ditropan, please continue to give this to your child, unless you are told otherwise.
  3. There are no special diet or other restrictions for this test.

If you have questions about this test, call the Urodynamics Laboratory at (319)356-4366.

Source: Christopher S. Cooper, MD, Pediatric Urologist
Last Reviewed: March 2006