Urodynamics at The Holly Hospital

What are urodynamic tests?

Urodynamic tests are a group of tests that check how well your bladder, sphincter muscles and urethra work together to store and release urine. Depending on your symptoms, you might have one or more of these tests done at the same appointment.

Why might I need urodynamic tests?

Your doctor may suggest this test to find out why your bladder isn't working as it should, and to help plan the treatment most likely to help you.

You may need it if you have:

• leaking urine (incontinence)
• a sudden, strong urge to pass urine, or needing to go more often than usual
• pain when passing urine
• trouble starting to urinate, or a slow, weak or stop-start flow
• difficulty emptying your bladder fully
• repeated urinary tract infections.

This test doesn't always find an explanation for your symptoms, but it gives your doctor useful information either way.

What are the benefits of urodynamic tests?

This test gives a clear, individual picture of how your bladder is working, helping your doctor recommend the treatment most likely to help, whether that's medication, pelvic floor exercises, or surgery.

It's a commonly performed and generally safe procedure. For most people, the value of getting a clear diagnosis outweighs the mild discomfort involved.

Are there different types of urodynamic test?

"Urodynamics" covers several different tests, and you may have more than one in the same appointment:

• Uroflowmetry: you urinate into a special funnel that measures your flow rate
• Postvoid residual measurement: checks how much urine is left in your bladder after you've been, using an ultrasound scan or a catheter
• Cystometric test (cystometry): measures how much your bladder can hold, the pressure inside it as it fills, and when you first feel the urge to go
• Leak point pressure measurement: records the bladder pressure at the point urine leaks, if this happens during the test
• Pressure flow study: measures the pressure your bladder generates and how quickly urine flows when you pass it
• Electromyography: checks the electrical activity of the nerves and muscles around your bladder, if nerve or muscle damage is suspected
• Video urodynamics: combines the tests above with X-ray or ultrasound images of your bladder filling and emptying.

How do I prepare for urodynamic tests?

You'll usually be asked to stop any medication you take for your bladder or prostate about a week beforehand, since these can affect the results. Your clinical team will tell you exactly which medications this applies to and confirm the timing.

• You may be asked to arrive with a comfortably full bladder
• You might be given a bladder diary to fill in for a few days beforehand, recording how much you drink and how much urine you pass
• Tell the team about any allergies, particularly to latex or iodine, and let them know if you might be pregnant
• If you think you have a urine infection, tell the team before your appointment, as the test may need to be postponed and treated with antibiotics first.

No other special preparation is needed. You can eat and drink normally otherwise.

What happens during urodynamic tests?

1. You'll talk through your symptoms with the specialist carrying out the test, and go over any bladder diary you've completed.
2. You'll pass urine into a special toilet or funnel that measures your flow rate; a painless ultrasound scan may check how much is left in your bladder afterwards.
3. You'll lie down (or sometimes sit or stand), and a thin, soft catheter is passed into your bladder through your urethra. A second one is placed in your rectum or vagina; lubricating gel is used to make this more comfortable.
4. The catheters are connected to a computer, and your bladder is filled slowly with sterile fluid. You'll be asked to cough or tell the team when you first feel the urge to go.
5. You'll be asked to pass urine into the machine once more to measure your flow, and the catheters are then removed.

Depending on the clinic and how many tests you need, this usually takes somewhere between 15 minutes and an hour. It shouldn't be painful, though it can feel a little uncomfortable or embarrassing; the team carrying it out are used to this and will support you throughout.

What happens after urodynamic tests?

Results from simple tests, such as uroflowmetry and cystometry, are often available the same day, and the specialist will usually discuss these with you along with any treatment options. Results from tests like electromyography or video urodynamics can take a few days.

It's common to feel mild discomfort or a burning sensation when passing urine for a short time afterwards, and you may notice a little blood in your urine, which should clear up within 24–48 hours. Drinking 2–4 extra glasses of fluid over the first 24 hours can help by diluting your urine and reducing irritation.

Contact your GP and mention you've recently had a urodynamic test if you develop signs of infection, such as a fever, chills, a burning sensation that doesn't settle, smelly urine, or generally feeling unwell, or if any bleeding is heavy or doesn't stop.

What are the risks or side effects?

Most people have no complications, though as with any test involving a catheter, there are some recognised risks:

• Burning or discomfort when passing urine, and blood in your urine: both affect between 1 in 2 and 1 in 10 people
• A urine infection needing antibiotics: affects between 1 in 10 and 1 in 50 people
• Difficulty passing the catheter, meaning the test has to be stopped and rearranged: affects between 1 in 10 and 1 in 50 people
• Difficulty emptying your bladder afterwards, needing a temporary catheter: affects between 1 in 50 and 1 in 250 people
• Not finding a clear cause for your symptoms, sometimes needing a repeat test: affects between 1 in 50 and 1 in 250 people.

If you have video urodynamics, this involves a small amount of extra X-ray radiation.