Post-Void Residual Urine Test

What is a post-void residual urine test?

A post-void residual urine test measures the amount of pee left in your bladder after you urinate. It can tell your healthcare provider if you’ve completely emptied your bladder.

When you go to the bathroom, your bladder should empty completely. But sometimes, pee stays in your bladder even after you feel like you’ve emptied it. The amount of pee that remains in your bladder after you urinate is called post-void residual (PVR). A small amount of pee left in your bladder is normal, but large amounts (called urinary retention) can be a sign of health conditions that need to be treated.

What is the PVR test used for?

A PVR test is used to diagnose urinary retention. Your healthcare provider may recommend it if you’re experiencing:

• Frequent urination.
• Urine leakage (incontinence).
• Frequent urinary tract infections (UTI).
• Feeling like you haven’t completely emptied your bladder after peeing.
• Bladder stones.

How does a post-void residual urine test work?

There are a few different methods for measuring PVR. The two most common are:

• Bladder catheterization. A healthcare provider drains any pee left in your bladder after you urinate using a catheter (flexible tube).
• Ultrasound. A provider can use a bladder scan or a transvaginal ultrasound in this method. Your provider uses a probe on your belly or in your vagina to get images of your bladder with sound waves. Your provider can use these images to calculate the amount of pee left in your bladder.

How do I prepare for a post-void residual urine test?

Most of the time, there’s no special preparation for a PVR test. You should be able to eat and drink normally. But ask your provider if there are any special instructions to follow before the test.

What happens during bladder catheterization to measure PVR?

Just before the bladder catheterization, you’ll go to the bathroom and empty your bladder as completely as possible. Then you’ll lie on your back on an exam table with your knees out to either side of you.

To perform a bladder catheterization PVR test, your provider will:

1. Clean and numb your urethra and the surrounding area with local anesthetic.
2. Insert a catheter through your urethra and into your bladder.
3. Drain any pee out of your bladder through the catheter.
4. Measure the amount of drained pee.
5. Remove the catheter.

What happens during an ultrasound PVR test?

Just before the ultrasound, you’ll go to the bathroom and empty your bladder as completely as possible. Then you’ll lie on your back on an exam table.

To perform a bladder scan test to measure PVR, your provider will:

1. Apply a special gel over your abdomen (belly) for a bladder scan or directly to the ultrasound probe for a transvaginal ultrasound.
2. Place the ultrasound probe on your abdomen (bladder scan) or into your vagina (transvaginal ultrasound).
3. Move the ultrasound probe to get the best images of your bladder. They’ll view and record images of your bladder on a nearby monitor.
4. Remove the probe. You can wipe off the excess gel after the procedure.

What can I expect after a PVR test?

Post-void residual testing is an outpatient procedure. You can go home or to work and resume your normal activities afterward. If you had a bladder catheterization, you may feel some discomfort as the anesthesia wears off. Drinking lots of water and peeing several times can help alleviate this feeling.

What are the risks of a PVR test?

Bladder catheterization has small risks of:

• Urinary tract infection (UTI). Your provider may prescribe antibiotics to reduce the risk of infection.
• Blood in your urine (hematuria).
• Damage to your urethra or bladder.

What’s a normal post-void residual volume?

Results of a post-void residual test report the amount of pee left in your bladder, or PVR volume. A normal post-void residual volume is between 50 mL (milliliters) and 100 mL. Your provider might consider different PVR volumes high or abnormal for you. They’ll explain what your results mean.

When should I know the results of a PVR test?

Ask your healthcare team when you can expect results. They’re often available immediately.

What causes high post-void residual volume?

High post-void residual volume (urinary retention) can be caused by a number of medical conditions, including:

• Blockage in your urinary tract, including tumors.
• Enlarged prostate.
• Medication side effects.
• Narrowed urethra.
• Nerve issues, like neurogenic bladder.

How do you treat post-void residual urine?

If you have a high PVR volume, your provider will suggest treatments based on what’s causing it. Medications, surgery and other procedures are possible treatments. Your provider will talk to you about your options for further testing and treatments.

When should I call my healthcare provider?

Go to an emergency room (ER) right away if you can’t pee at all. Contact your healthcare provider if you have:

• Abdominal pain or swelling.
• Pain when peeing.
• Fever.
• Cloudy or foul-smelling pee.