Urinary catheterisation is a medical procedure used to drain and collect urine from the bladder.
A thin, flexible tube called a catheter is inserted into the bladder, usually along the tube urine naturally passes through (urethral catheter), or through a hole in your abdomen directly into the bladder (suprapubic catheter).
The catheter usually remains in the bladder, allowing urine to flow through it and into a drainage bag.
Why is urinary catheterisation needed?
A urinary catheter can be used on a short or long term basis.
Short-term catheterisation may be needed to remove urine from the bladder for a short period of time if there is something stopping you emptying your bladder normally.
For example, this could be because the bladder cannot empty if there is an obstruction (blockage) or it is unable to generate enough force to propel urine down the waterpipe.
If the urethra has become blocked, it may be because of scarring (stricture), prostate enlargement, or, rarely, a stone. A catheter will be fitted until the underlying condition can be treated.
Short-term catheterisation may also be used in preparation for some types of surgery, such as operations on the womb or ovaries and procedures involving the large bowel. It may also be used for other operations where a long period of recovery is anticipated.
Other situations where a catheter may be used include during childbirth (to drain the woman's bladder), and to clear the bladder of any blood clots and debris following an injury to the bladder or after surgery to that area.
A urinary catheter may be needed for a long time if it's not possible to treat the underlying condition that prevents the bladder from emptying naturally.
Long-term catheterisation can be used when a person is confined to bed and is too weak to go to the toilet. It is also sometimes used as a treatment for urinary incontinence when other types of treatment have failed.
If a person is unable to empty their bladder because of bladder weakness (detrusor hypocontractility) or nerve damage (neurogenic bladder), long-term catheterisation is a possible treatment option.
If you require urinary catheterisation for a long time, you may be trained to insert a catheter when needed. This is known as self-catheterisation and involves catheterisation for a short period to allow the bladder to empty before the catheter is removed. This is likely to be carried out several times a day and avoids the problems associated with permanent catheterisation.
In some cases, catheters can be used to obtain a clean urine sample to test for bacterial infections. This is a sample that has not been contaminated by bacteria from your hands or genitals.
A catheter can also be used to deliver medication directly into the bladder, such as chemotherapy medications used to treat cancer of the bladder.
Types of catheters
There are two main types of catheter. They are:
- intermittent catheter – where the catheter is temporarily inserted into the bladder and removed once the bladder is empty
- indwelling catheter – where the catheter remains in place for many days or weeks and is held in position by a water-filled balloon in the bladder
Many people prefer to use an indwelling catheter because it is more convenient. However, indwelling catheters can be complicated by problems such as bladder spasm, infection, blockage and leakage around the catheter. These problems are reduced if intermittent catheterisation is used.
Read more about how urinary catheterisation works and the risks of catheterisation.
The website of The British Association of Urological Surgeons (BAUS) provides more information about the management of a urethral catheter.