Healthcare and Medicine Reference
4 cm long. The male urethra passes through the prostate gland
which may make catheterisation more diffi cult if the prostate is
Council tip catheters: have a small hole in the end to allow pas-
sage over a guidewire.
Box 18.1 Equipment for insertion of a urinary catheter
There are different catheters for males and females due to the
differing length of urethra. A male catheter can be used in female
patients. Foley catheters have a balloon to keep them in place.
Originally invented by Fredrick Foley, the intention for use was
to achieve haemostasis and so there were different sizes of balloon
available - 10, 20 and 30 mL. You will most commonly use the
10-mL balloon for urinary catheterisation where the balloon acts
to keep the catheter in situ. Do not infl ate the balloon with air as
the balloon will fl oat and may cause irritation. Use sterile water
(saline can crystallise making it diffi cult to defl ate the balloon).
Most catheters come with a prefi lled syringe.
Catheters also vary in external diameter which is measured in
charrière (Ch); 1 charrière = 0.33 mm. 12, 14 and 16 Ch are most
commonly available. A larger diameter will allow quicker drain-
age. Larger sizes should be used if clots or postoperative debris are
present in the bladder. In general, use a size 14 Ch.
Catheters are made from different materials depending upon
how long they are intended to be in situ.
Most hospitals stock catheter packs which contain most of the
things you will need. While assembling your trolley you will need the
two pairs of sterile gloves
incontinence pad to place underneath the patient
lubricant - commonly contains lidocaine 2% and chlorhexidine
0.25% alongside lubricating gel
catheter pack + 10-mL syringe (normally prefi lled)
cleaning solution (saline or chlorhexidine-based cleaning solution)
catheter: keep the stickers from the packaging to stick into the
catheter bag (depending on indication or need: can be a leg-
bag that attaches to the patient's inside leg, an hourly bag for
accurate measurement or 4-hourly bag)
Plain latex: 7 days maximum, ideally 3 days. The latex gradually
absorbs fl uid, increasing its external and internal diameter, reduc-
ing urine fl ow and causing increasing discomfort.
Plastic/polyvinyl chloride: used in theatre or for intermittent self-
catheterisation. They are prone to bacterial contamination. They
are a harder material, less fl exible and can be uncomfortable.
Polytetrafl uoroethylene: covers latex making the catheter
smoother and less irritating. There is less fl uid absorption but the
polytetrafl uoroethylene wears off after 3-4 weeks.
Figure 18.3 Equipment required for urinary catheterisation.
Latex coated. This can be either with hydrogel, polymer hydromer
Step-by-step guide: urinary catheterisation
or silicone elastomer, making the catheter smoother, reducing
risk of bacterial colonisation and preventing fl uid absorption.
The catheter can be kept in for up to 12 weeks.
Silicone: used in patients allergic to latex. Silicone is a less fl exible
ensure they consent to the procedure.
Set up your trolley (Box 18.1 and Figure 18.3)
Give a full explanation to the patient in simple terms and
Prepare your trolley as a sterile fi eld. Wear a plastic
disposable apron and sterile gloves, and take alcohol hand
rub with you.
material and the sterile water in the balloon diffuses gradually
out into the bladder: a note should be made to check and top
up the balloon after 6 weeks. The thickness of the silicone is less
than latex-based catheters. Therefore they have a larger internal
diameter with subsequent better drainage to comparable Ch sizes
of latex catheter. Again, they can be kept in for up to 12 weeks.
Set up your sterile fi eld and put on sterile gloves.
Position the patient lying supine on an incontinence pad and main-
tain their dignity at all times (Figure 18.4a). Obese or pregnant
women may need to be positioned differently with knees bent to a
greater extent or in the left lateral position if heavily pregnant.
Clean around the urethral meatus with cleaning solution
Three-way catheters: these have a third port that allows irrigation
to run into the bladder. The catheter itself has a large diameter to
allow blood and debris to pass into the drainage bag.
Coude/Tiemann catheters: have a 45° bend at the tip allowing
(normal saline is acceptable) using a one wipe technique,
cleaning downwards then disposing of the gauze (do not place
the dirty gauze back into your sterile fi eld) (Figure 18.4b). Repeat
this until satisfi ed the area is clean. In females you will need to
easier passage through an enlarged prostate.