Post-void residuals: Checking how well your child's bladder is emptying

What is a post-void residual test?

The purpose of the post-void residual test is to see how well your child's bladder is emptying after surgery. Post-void means after urinating. Residual means left over. So the post-void residual is the amount of urine (pee) that is left in the bladder after your child has finished urinating (peeing).

These instructions explain how to check your child's post-void residuals at home. The instructions are for a child who has a suprapubic catheter.

Each time your child pees, you will measure the amount of urine your child passes. After your child finishes, you will remove the urine that is left in the bladder with a catheter and measure it as well.

Usually, you will need to do this every time your child pees until your child's next clinic visit. Based on the measurements, your child's suprapubic catheter may be removed during the clinic visit.

Step-by-step instructions for a post-void residual test

Before you start, you will need the following equipment:

• A "hat" to measure urine in the toilet. The hat is a hat-shaped bowl with a large brim that sits upside-down on your toilet. Your child then sits on the toilet seat and pees into the hat.
• An alcohol wipe.
• A container to measure urine from the catheter.

When you have collected this equipment, follow these steps:

1. Wash your hands with soap and water.
2. Place the hat in the toilet to collect and measure urine. Ask your child to pee into the hat.
3. Using the alcohol wipe, clean the connection between the suprapubic catheter and the plug. Put the wipe aside.
4. Remove the plug from the end of the catheter. Set the plug aside in a clean place.
5. Place the end of the catheter in a container. Let the urine drain into the container until the flow of urine stops.
6. Clean the catheter plug with the alcohol wipe. Put the plug back into the end of the catheter.
7. Measure the amount of urine in the hat and the amount of urine drained from the catheter into the container. Write down each amount. Report these amounts when you return to the hospital.