Published by Bupa's health information team, December 2008.
This factsheet is for people who are planning to have urodynamic study, or who would like information about it.
Urodynamic study involves a range of tests to measure bladder function.
Your care will be adapted to meet your individual needs and may differ from what is described here. So it's important that you follow your doctor's advice.
Urodynamic study can help find what's causing urinary incontinence (involuntary leakage) or retention (difficulty in passing urine). It checks how your bladder, the muscle around the neck of your bladder (sphincter) and the tube through which urine flows out of the body (urethra) are working.

The position of the bladder and surrounding structures
The purpose of urodynamic study is to find out whether your:
Your doctor may suggest alternative imaging tests, such as plain X-rays of the urinary system, CT (computed tomography) scan or renal ultrasound. Urodynamic study is usually only done if an obvious cause of incontinence or voiding problems isn't found.
Urodynamic study is usually done as an out-patient procedure. This means you have the test and go home the same day.
You may be asked to keep a record of how much you urinate (called a voiding diary) over three days. You will need to record what type of fluid you drink, when and how much, and the timing and volume of urine output each day. You will need to record when you feel urgency or leak urine. The hospital will give you detailed advice about how to complete a voiding diary beforehand. This diary helps your doctor better understand your bladder problem. You may also be asked to stop any current bladder medication for at least a week beforehand.
You can eat and drink as usual before having urodynamic study. You may be asked to come to your appointment with a full bladder.
At the hospital your nurse may check your heart rate and blood pressure, and test your urine for infection. If you have a urinary infection (known as a urinary tract infection, UTI) your doctor may decide not to proceed with the test and ask you to come back after the infection has cleared.
The procedure may involve X-rays to help your doctor confirm your diagnosis. A radiographer (a health professional trained to perform imaging procedures) usually operates the X-ray machine and produce images on film or in digital format.
You must tell your doctor or radiographer about any medicines you are taking and if you have any allergies, glaucoma or heart disease. If you are a woman of childbearing age, you must tell your doctor or radiographer if you could be pregnant. X-rays are safe for adults, but may harm your developing baby. If you're pregnant, your doctor will discuss alternatives to the procedure.
Your doctor will usually ask you to sign a consent form. This confirms that you understand the risks, benefits and possible alternatives to the procedure and have given your permission for it to go ahead.
Urodynamic study usually takes 15 to 30 minutes.
You will need to remove your lower clothing and put on a hospital gown. You may need to lie back on a special X-ray table, which can be moved into different positions.
Fine tubes (catheters) with sensors attached to the tip are passed into your bladder through the urethra, and placed in your vagina or rectum. You doctor may apply a local anaesthetic gel around the entrance of your urethra beforehand to minimise any discomfort. You may feel the sensation of needing to pass urine as the catheters are put in.
With the catheters in place, the study may include the following tests.
You will be able to go home when you feel ready. You can drive if you wish.
Your results may be discussed with you immediately after the test or at a later date. Alternatively, a report may be sent to the doctor who recommended your test.
Drink plenty of clear fluids over 48 hours to help flush your bladder and reduce your risk of urinary infection.
Contact your GP if you develop any of the following symptoms, as you may have developed an infection:
Urodynamic study is commonly performed and generally safe. However, in order to make an informed decision and give your consent, you need to be aware of the possible side-effects and the risk of complications of this procedure.
If the test involves X-rays, you will be exposed to some X-ray radiation. The level of exposure is about the same as the background radiation that you would receive naturally from the environment over 12 to 14 months. X-rays can harm a developing baby. If you are, or think you may be pregnant, tell your doctor before your appointment.
These are the unwanted but mostly temporary effects of a successful procedure.
Side-effects of urodynamic study include:
This is when problems occur during or after the procedure. Most people are not affected. Complications of urodynamic study are uncommon but can include:
The exact risks are specific to you and differ for every person, so we have not included statistics here. Ask your doctor to explain how these risks apply to you.
This information was published by Bupa's health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Bupa doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
Publication date: December 2008
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