Urodynamic studies are specialised tests used to assess how well your bladder is working. These tests help your healthcare team understand the causes of urinary symptoms such as incontinence, urgency, or difficulty emptying the bladder.
The procedure involves filling your bladder with fluid and measuring how your bladder responds as it fills and empties. Your doctor or nurse will only recommend this test if it is important for deciding how best to manage your symptoms.
Why might I need this test?
There are no real alternatives to urodynamic studies, apart from treating your symptoms without the extra information this test can provide. The results can help guide your treatment and management options.
What happens on the day of the procedure?
- A specialist nurse will review your medical history and medications, and discuss the procedure with you to confirm your consent.
- Please inform staff if you have any allergies, especially to latex.
- You will usually be asked to arrive with a comfortably full bladder. This allows the team to:
- Measure your urinary flow rate before the main test (by passing urine into a special machine).
- Test a sample of your urine for infection. If infection is found, your procedure may be postponed and you may be given antibiotics.
What does the procedure involve?
- The test is usually performed by a specialist nurse and may take up to an hour.
- You will lie on a couch while a fine plastic catheter (tube) is gently passed through your urethra (waterpipe) into your bladder. Sometimes, the catheter may be passed through your tummy wall (if you have a suprapubic catheter) or through a Mitrofanoff channel.
- A second, fine catheter is placed into your rectum or vagina. If you have a bowel stoma (ileostomy or colostomy), the second catheter may need to be placed in your stoma, so please bring a spare stoma bag.
- The catheters are taped to your leg and connected to a computer system to measure pressures.
- The test may be done with you lying down, sitting, or standing.
- Your bladder is slowly filled with saline (salt solution) through the catheter.
- You may be asked to cough or strain during the test and to tell the team when you first feel the urge to pass urine.
- If incontinence (leakage) is one of your symptoms, the team may try to reproduce this during the test. The clinical team will be supportive and respect your dignity throughout.
- You will be encouraged to hold on until your bladder feels very full.
- At the end, you will be asked to pass the fluid in your bladder into a flow-rate machine again.
- All catheters are then removed and you can wash and dress yourself.
- An outpatient appointment will be arranged for you to discuss the results and next steps with your consultant.
Are there any risks or after-effects?
Most after-effects are mild and temporary. Possible risks include:
- Burning or discomfort when passing urine (affects between 1 in 2 and 1 in 10 patients)
- Blood in your urine (between 1 in 2 and 1 in 10)
- Infection in your urine requiring antibiotics (between 1 in 10 and 1 in 50)
- Inability to pass the catheter, so the procedure has to be abandoned and further tests arranged (between 1 in 10 and 1 in 50)
- Retention of urine (inability to empty your bladder) requiring a temporary catheter (between 1 in 50 and 1 in 250)
- Failure to find the cause of your symptoms, possibly requiring a repeat test (between 1 in 50 and 1 in 250)
What can I expect when I get home?
- Drink plenty of fluid for the first 24 to 48 hours to help reduce the risk of urine infection.
- Some patients may be given antibiotics, especially if at higher risk of infection.
- Any antibiotics or other tablets you need are usually arranged and dispensed from the hospital pharmacy.
- A copy of your discharge letter will be sent to your GP.
- A follow-up appointment will be arranged for you with your consultant.
General information and preparation
Before your procedure, please tell the medical team if you have:
- An implanted foreign body (such as a stent, joint replacement, pacemaker, heart valve, or blood vessel graft)
- A regular prescription for a blood thinning agent (e.g. warfarin, aspirin, clopidogrel, rivaroxaban, dabigatran)
- A present or previous MRSA infection
- A high risk of variant-CJD (e.g. if you have had a corneal transplant, neurosurgical dural transplant, or human growth hormone treatment)
Before you go home:
- Make sure you understand what has been done and ask the nurse if everything went as planned.
- Let staff know if you have any discomfort.
- Ask what you can and cannot do at home.
- Make sure you know what happens next.
- You will be given advice about what to look out for when you get home.