Urodynamics
Figure 1: Urodynamic study.
What are the indications for urodynamic studies?
You will be referred for this procedure if your urologist needs more information about your bladder function before offering further treatments. It is often used to assess
The cause of lower urinary tract symptoms to assess potential benefit of primary / re-do prostate surgery
The nature and severity of urinary leakage
To assess the impact of neurological conditions on the urinary tract
What pre-operative work up is needed?
Your urologist will organise any necessary urine and blood tests and imaging scans at your consultation prior to your procedure.
If you take any medication for your lower urinary tract symptoms such as Ditropan, Vesicare or Betmiga, you should discuss with your urologist if these need to be stopped before your procedure.
Please ensure you return any admission forms given to you to be filled out back to the hospital.
What happens on the day of the procedure?
You do not need to fast for this procedure. You should bring a list of your medications, any recent scans or reports with you to the hospital. After you are admitted from the admission lounge, your urologist and a nurse will see you to discuss the procedure. You may be given a hospital gown to change into. You must let the staff know if you have any allergies, especially to latex.
We usually ask you to come for the procedure with a comfortably full bladder. This allows us to measure your urinary flow rate; which involves passing urine into a special machine, before we carry out the urodynamic studies.
We will also test a sample of your urine for infection – if there is evidence of infection, we may postpone your procedure for a week or two and give you a course of antibiotics.
What does this procedure involve?
It involves filling your bladder with fluid through a small, soft catheter tube and measuring how your bladder responds to filling; we also measure how well your bladder works when you pass urine. The test is usually performed by your urologist and /or a specialist nurse.
Sometimes prior to your urodynamics, a flexible cystoscope will be passed into your bladder to visualise your urethra (waterpipe) and bladder. As you lie on a table, a fine soft plastic catheter tube will be passed through your urethra into your bladder. A second, fine catheter is gently inserted into your rectum (back passage). Once all the catheters are in place, they will be taped to your leg and connected to a computer system, which measures the pressures.
The test maybe done with you lying or standing. Your bladder will slowly be filled with fluid through the catheter. You may be asked to cough or strain during the test and to tell us when you feel a desire to pass urine. When the bladder is full, you will be asked to pass the fluid in your bladder into a flow-rate machine again
If you are having a videourodynamic study, we may take X-ray pictures throughout the test.
In the end all the catheters will be removed and you can wash and dress yourself.
Are there any risks or side effects?
Urodynamic studies are quite safe with major risks being very rare but some patients may experience some of these side effects including:
Burning and discomfort on passing urine 50-60%
Blood in your urine 10-20%
Infection in your urine requiring antibiotics 5-10%
Retention of urine (inability to empty your bladder) requiring a temporary catheter to be put in your bladder 2-5%
What can I expect when I get home?
You should drink plenty of fluid for the first 24 to 48 hours to help reduce the risk of urine infection.
Some (but not all) patients may be given antibiotics afterwards. Your urologist will inform you if this is required.
In most cases, you can return to normal activities including driving the next day if you are comfortable and pain free.
What follow-up will I need?
Your urologist will make an appointment to discuss the results with you in the next 2-4 weeks and any discuss further treatments that may be required depending on the results.