Urodynamics are a range of tests to study the pressure and flow in the bladder as it fills up, and the flow through the water pipe as you urinate, to assess bladder function against the outlet which is the prostate (or paraurethral glands in women) and water pipe.
Bladder pressure tests are recommended for patients where doctors think that minimally invasive treatment might be necessary, e.g. male patients suffering from lower urinary tract treatment who having tried previous treatment are now facing an operation to vaporise their prostrate need a bladder pressure test.
Women experiencing urinary leakage, either stress leakage or mixed urinary leakage (leakage caused both by pressure on the bladder and after a sudden urge to urinate) would also be recommended to have a bladder pressure test.
By replicating what happens to your bladder when it fills with water and you pass urine, the test enables doctors to diagnose your bladder problem and prepare a treatment plan.
There are no alternative tests that enable doctors to obtain the information they can find out in a bladder pressure test.
Before investigation, the consultant and clinician will assess that whether you will benefit from bladder pressure testing.
If you are taking medicines for your bladder, such as oxybutinin tablets or patches, solifenacin, tolterodine, fesoterodine or mirabegron, you will need to stop taking them five days before the test.
The consultant will then give you a bladder record charge or bladder diary to record the input of fluid and output of urine and document the number of times number of times they are leaking urine and getting wet. This will give the capacity of the bladder.
You will be given a leaflet describing the bladder pressure test.
A two hour attendance is required and the test takes 40 minutes. You don't necessarily need to bring anyone to take you home and you don't have to take antibiotics prior to the test.
It is clearly explained to the patient that this is an embarrassing test - multiple people are present, including radiographers, nurses and trainees.
You should try to come to the test with a comfortably full bladder, as the first part of the test involves emptying the bladder into a machine called a flowmeter, to examine how much urine you pass and the flow. If there is any infection in the urine, it will not be possible to take the test - you will be given antibiotics and will need to rebook.
You will be asked to undress from the waist down and change into a gown that opens at the back. Once changed, you will be invited to lie down on a couch, and one tube is passed into the bladder and another into the rectum. Women then sit on the toilet and men stand in front of the toilet and the tubes are connected to a bag of fluid that slowly fills up the bladder at a controlled rate (only a small amount of fluid passes into the rectum).
This enables the doctor to measure the pressure both inside and outside the bladder. Once the bladder is full, you will be asked to urinate with the tubes still in, showing what happens to the bladder as it empties.
You may feel a little discomfort when the bladder tube is inserted due to the anaesthetic gel used but this passes almost immediately. You may also feel discomfort as the bladder is filled during the test.
After the procedure is completed, the tubes are removed and you will be able to use the toilet facilities. The doctor will give the result then and there, and advise you to come in to the clinic for a full consultation. At the end, you are issued a prescription for antibiotics and will be advised to drink plenty of fluid.
There is no recovery period.
Very rarely, patients will experience infection and bleeding following the test.