Intermittent catheterisation (IC) is the act of passing a catheter into the bladder to drain urine via the urethra, (or occasionally another catheterisable channel such as a Mitrofanoff continent urinary diversion). The catheter is removed immediately after urine drainage.

Intermittent catheterisation was originally advocated by Lapides et al (Lapides 1972) and is widely for urinary drainage by people with neurogenic bladder dysfunction or incomplete bladder emptying. The technique avoids or reduces many of the risks associated with indwelling catheters, such as urinary tract infection (UTI).

Intermittent catheterisation can be taught to people of all ages who have sufficient manual dexterity and motivation to manage the technique. This includes very elderly people and children as young as four years old with parental supervision (Eckstein 1982). Carers can also be taught the procedure where this is acceptable to both patient and carer. Disabilities such as blindness, lack of perineal sensation, tremor, mental disability and paraplegia do not necessarily preclude people from mastering the technique if they have sufficient manual dexterity and motivation.

An individualised care plan is developed to identify an appropriate catheterisation frequency, based on assessment of their voiding problem through discussion, frequency‐volume charts and ultrasound bladder scans for residual urine. Some people need to catheterise several times per day, others only infrequently. Advantages of intermittent catheterisation over indwelling catheterisation include:

• greater opportunity for individuals to reach their own potential in terms of self‐care and independence;

• reduced risk of common catheter‐associated complications;

• better protection of upper urinary tract from reflux;

• reduced need for equipment and appliances eg. drainage bags;

• greater freedom for expression of sexuality;

• potential for improved continence between catheterisations.

Catheterisation techniques vary as follows:
(i) Sterile catheter (single‐use) with sterile (no‐touch) catheterisation technique (SS).
(ii) Sterile catheter (single‐use) with clean technique (SC).
(iii) Clean catheter (reusable) with clean technique (CC).

There is variation in the types and characteristics of catheters used in IC techniques and this adds complexity to the selection of products and to comparative analysis of performance. Plain uncoated catheters are packed singly in sterile packaging and are sometimes reused after cleaning. The success of cleaning is affected by the method used (eg. soap & water, boiling, disinfectants, microwave) and by the method of storage of cleaned catheter. Some catheters are coated, most commonly with a hydrophilic coating designed to aid lubrication and comfort in use, although catheters are also available with coatings containing an antibiotic element. Coated catheters are intended for single use only, and therefore over time they are more expensive than plain, uncoated reusable catheters. Also available are pre‐lubricated catheters and sterile packs containing a coated catheter along with sterile water for soaking and/or an integral drainage bag, intended to allow the user greater freedom in terms of where and when he or she catheterises. Some products are also designed to facilitate a 'sterile' no‐touch technique. There is also variation in the design of catheters themselves in terms of material, length, flexibility, and whether drainage eyes are polished or unpolished. Although these characteristics may be important for individual users they are not addressed in this review.

Complications of intermittent catheterisation
Wyndaele (Wyndaele 2002) reviewed 82 studies of complications of intermittent catheterisation. Urinary tract infection (UTI) was the most common complication and catheterisation frequency and the avoidance of bladder over‐filling were recognised as important prevention measures. Prostatitis was an identified risk in men. Epididymitis and urethritis were relatively rare. Trauma from catheterisation was noted to occur regularly but lasting effects were limited. Estimates of the prevalence of urethral strictures and false passages increased with longer use of IC but the study concluded that the most important preventative measures were good education of all involved in IC, good patient compliance, use of an appropriate catheter material, and good catheterisation technique. Similar findings were recently reported by Campbell et al (Campbell 2004) in a follow‐up of children with spina bifida who had used intermittent catheterisation with an uncoated PVC catheter for at least 5 years. The incidence of urethritis, false passage, or epididymitis was very low while compliance with the protocol was excellent.

Nevertheless, concern remains about the long‐term implications of routine intermittent catheterisation and recent innovations have attempted to address this issue. Hydrophilic polymers which can bind lubricating liquids have been shown to reduce friction during catheter insertion but any relationship to catheter‐associated infection is less clear (Cottenden 2005). Vaidyanathan et al (Vaidyanathan 1994) studied the degree of urethral inflammation by urethral cytology in two groups on IC: one using uncoated PVC catheters with lubricant; the other using hydrophilic coated catheters. The group using hydrophilic coated catheters had significantly less urethral inflammation. However, they are more expensive in the long‐term and questions about whether better patient satisfaction and decreased urethral irritation can justify the greater expense remain largely unanswered. Hydrophilic catheters themselves vary in type and degree of coating (Fader 2001) and, may cause urethral or meatal irritation. Hedlund et al (Hedlund 2001) reviewed the literature on IC (28 studies) and called for a prospective, randomised, long‐term, multi‐centre study to address cost‐benefit and cost effectiveness. A further aspect of the cost‐effectiveness debate relates to whether catheters designated for single use by manufacturers should only be used once or whether 'single use' can be interpreted as re‐use by a 'single patient' in the case of patients who are self‐caring at home.

A recent trial by De Ridder et al (De Ridder 2005) suggests that UTI is reduced in hydrophilic catheter users compared to uncoated PVC users, a finding that deserves further exploration. It is difficult to know the prevalence of UTIs associated with intermittent catheterisation as the reports vary widely. This is, at least partially, due to the various definitions of UTI based on bacteriuria alone (asymptomatic) or symptomatic UTI (with or without clearly defined criteria); evaluation methods used; different catheterisation techniques; different frequencies of urine analysis; the administration or not of prophylactic antibiotics; the group of patients studied (including sex, functional ability and other behavioural and personal hygiene factors).

This review has two primary aims. The first is to assess whether and under what circumstances, clean catheterisation is as good as sterile catheterisation. The second is to determine if coated catheters are better than uncoated catheters in relation to defined outcome measures. A further aim is to compare different catheter cleaning strategies. It must be recognised that IC takes place in a range of settings (e.g. hospital or community) and this will be taken into account where possible. Comparisons between different types of bladder drainage will not be addressed as this has been examined in existing Cochrane Reviews including: 'Catheter policies for management of long‐term voiding problems in patients with neurogenic bladder '(Jamison 2004); and 'Urinary catheter policies for long‐term bladder drainage' (Niel‐Weise 2005).