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The first urinary catheter is reported to have been passed by John of Gaddesden (1300-1367) and catheterization was illustrated in some of the earliest texts. When a tube could not easily be passed into the bladder to relieve the obstruction, other procedures to enter the bladder were devised, some quite novel, though all probably as painful and dangerous as the condition itself! Benjamin Franklin was a prolific inventor, not least of medical devices. Because his brother suffered from various urinary problems, he invented the first flexible urinary catheter — made of bendy silver wire and covered with animal stomach casings.

A urinary catheter is a soft hollow tube inserted into the bladder to drain urine and occasionally to insert medication and other solution preparations.

The use of urinary catheters is not new. Catheters date back as far as 300BC with reports of them being made from dried reeds, palm leaves, animal skins and cheese glue. Further developments led to metal catheters made from gold, tin, lead and silver. However, more malleable catheters became available in 1844 with the perfection of the vulcanisation of rubber.

Rubber is also known as Latex, most of which comes from a single rubber tree called Hevea Brasiliensis native to South America. After natural latex is processed (vulcanised), it becomes a rubber with excellent mechanical properties in that it is tensile, can be elongated, and has tear resistance and resilience. This is the reason why several latex products, including catheters, are manufactured for healthcare usage.

If a catheter is to remain in the bladder for a prescribed period of time, an indwelling catheter will be used. These are also known as Foley catheters, named after their inventor, Fredrick Foley, in 1934. Indwelling urinary catheters should be used only after alternative methods of management have been considered.

Before deciding which type of indwelling catheter would suit you best, the nurse or doctor will consider several key issues:

Length of Indwelling Catheter

Like intermittent catheters, adult indwelling catheters are available in a standard (male) length (40-45cm) and a shorter female length (20-26cm).

For children, paediatric standard length catheters (approximately 30cm) are available but if a child requires a size 12ch then a standard (male) or female length catheter should be used.

Catheter Balloon Infill Size

Foley catheters differ from intermittent catheters in that they have an inflatable balloon at one end and an inflation channel at the other. The purpose of the inflated balloon is to enable the catheter to be anchored into the base of your bladder for continuous drainage of urine. The balloon is filled with the correct amount of recommended sterile water inserted through the inflation channel during the catheterisation procedure.

For adults, the amount of sterile water used to fill the balloon should routinely be 10mls. However, it is not uncommon for a short-term 30 ml balloon to be used following surgery to drain away debris and blood clots. Your clinical need for catheterisation should be reviewed regularly and the urinary catheter removed as soon as possible. If still required, it should be replaced with one with a smaller 10ml balloon. For children a 3-5ml balloon is commonly used.

Materials & Duration

Materials that the indwelling catheter is made from determine the maximum length of time it can remain in the bladder.

Note: Some may contain latex.

It is important that you tell your nurse and/or doctor if you have a known latex allergy/sensitivity.
Short-Term (Mostly used in hospitals)
E.g. latex and latex bonded with PTFE catheters
Maximum 4 weeks.
Long-Term (Mostly used in the community)
E.g. latex with hydrophilic coating, latex with polymer hydromer coating, latex with silicone elastomer coated catheters and all silicone catheters.
Maximum 12 weeks.
For more information refer to the section entitled “What Does Indwelling Catheterisation Entail?
Diameter
Both intermittent and indwelling catheters are also made in a variety of French gauge (Fr) diameter sizes known as Charrière sizes. To give you some idea, 1 Charrière is equal to 0.33mm. This means that a 12Ch catheter is 4mm and a 16Ch catheter is 5.3mm in diameter.
Average diameters are:
Adult Female: 12-14ch
Adult Male: 14-16ch
Children: 6-10ch with a size 12ch from age 14 years upwards

Of course, larger or smaller sizes can be used following assessment by your healthcare professional. Taking all these factors into account, it is easier for you to understand the importance, knowledge and care your healthcare professional exercises to make sure that the most suitable indwelling catheter is selected for your use.

How is the catheter inserted into the bladder?

Having a basic anatomical understanding of the lower urinary tract will help you to understand how the catheter is inserted into the bladder.

The most common route for catheterisation is via the urethra. The urethra is the anatomical tube that allows urine to be drained from the bladder to an appropriate external receptacle – normally the toilet. In women, the urethra is approximately 4 cm long so the catheter doesn’t have far to travel to get into the bladder. In men the urethra is longer at approximately 18-20cm.

Catheters may be used as single use items known as intermittent catheters.
Disposable intermittent catheters are usually made from synthetic materials such as PVC or silicone and have a thin lubricating coating to make them smooth and comfortable when used. However, reusable metal intermittent catheters are available which some individuals prefer to use with a lubricating jelly. Whichever type of intermittent catheter is selected, it is the patient that will decide which one is the most comfortable and manageable.

Intermittent catheterisation involves the temporary placement of a catheter into the bladder for just a few minutes in order to drain away the urine. It is the preferred method of catheterisation in patients with bladder dysfunction since the risk of developing a urinary tract infection is reduced compared with that of an indwelling catheter.

The intermittent catheterisation procedure is not new as it is believed to have been undertaken some 300BC years ago for short-term relief when voluntary urination was not an option or was proving to be difficult. Various tubing materials have been used for this procedure ranging from onion leaves to catheters made from silver, stainless steel, polyvinyl chloride (PVC) or silicone as developments occurred.

Today, intermittent catheters are more advanced with the development of different coatings that are added to the surface of the PVC or silicone tubing in order to ease insertion. The gentle passage of a coated catheter into the bladder, if undertaken correctly, is smoother and safer thereby reducing the risk of trauma along the way.

Intermittent catheterisation is sometimes referred to as Clean Intermittent Catheterisation (CIC). Studies have shown that undertaking a clinically clean procedure as opposed to a sterile procedure does not increase the risk of infection.

Additional benefits include self-care and independence as well as reducing the need for equipment such as drainage bags, especially as the intermittent catheter can be used to direct urine into the toilet. Also, there are fewer barriers to intimacy and sexual activities. Reduced urinary symptoms such as frequency, urgency and leakage in between the catheterisations are a further benefit. So, with these in mind it easy to understand why intermittent catheterisation is the preferred option.
Initially, your CIC procedure will be undertaken by a registered nurse or doctor. The nurse will teach and support you to undertake the procedure yourself as prescribed. This is usually between 1-4 times daily. Alternatively, a carer may be taught how to catheterise you intermittently if you are unable to do it yourself for whatever reason e.g. poor manual co-ordination.
I have been told I will need to catheterise following a urinary diversion operation (ie mitrofanoff procedure, bladder removal operation or bladder enlargement surgery)

Can this be done intermittently?

Yes. Intermittent catheters can be used to drain urine from the bladder following any of the above procedures which do not require a stoma bag to be fitted on to your abdomen in order to collect the urine. Instead, as the stoma is designed so as not to leak urine and the bladder or new pouch is unable to sufficiently contract to empty the bladder which is why intermittent catheterisation is necessary. The below image (Figure 9) shows an intermittent catheter inserted into the bladder via the abdominal stoma and channel made from the appendix following a Mitroffanoff diversion.