It has been estimated that in 2017, there were over 90 000 long-term catheter users in the UK (Gage et al, 2017). Catheterisation can be temporary or indefinite, and long-term catheterisation is defined as that which lasts longer than 30 days. The term ’indwelling’ refers to either urethral (’Foley’) or suprapubic catheters (Continence Product Advisor, 2019). Despite concerns regarding complications with long-term urinary catheterisation, for many patients with serious bladder or other conditions, the use of an indwelling catheter is an integral part of being able to manage at home when alternative management methods have failed or are impossible. For some patients, this may be worth the risks, including the high risk of catheter-associated urinary tract infection (CAUTI), as well as bypassing, blockage, dislodgement and, over the long term, skin breakdown (Wilde et al, 2013). CAUTIs are the primary disadvantage of the long-term catheterisation.
Uses of long-term catheterisation
Indications for long-term catheterisation are given in Box 1. Given the known risks associated with long-term catheter use, as well as the overuse for convenience in the older population, catheters must only be used after careful consideration of the intended gains, discussion of the risks and benefits, and ideally only for specific indications (Inelmen et al, 2007). The primary uses of indwelling catheters are urinary retention and intractable urinary incontinence. The National Institute for Health and Care Excellence (NICE) guidelines for urinary incontinence in women offer some evidence-informed direction on catheter use for specific indications, such as chronic urinary retention in women who are unable to manage intermittent self catheterisation; where there are skin wounds, pressure ulcers or irritations that are being contaminated by urine; when there is intolerable distress or disruption caused by bed and clothing changes; and where the patient expresses a preference for this form of management (NICE, 2019). Suprapubic catheters may be associated with lower rates of symptomatic urinary tract infections (UTIs), ’bypassing’ and urethral complications than indwelling urethral catheters are and may be preferred long-term option. They are also easier to replace than indwelling urethral catheters (Chapple et al, 2015).
Alternatives to long-term catheterisation
If possible, alternatives should be trialled before resorting to an indwelling catheter (Box 2). These alternatives will vary depending on the underlying indication. Many patients see a catheter as a convenient solution to their problem, particularly when incontinence is intractable—this view can be a source of friction between the healthcare provider and patient. However, this friction could be resolved with shared decision-making, which entails a detailed discussion between the patient and healthcare provider of the indications for long-term catheterisation, alternatives trialled and reasons for failure and the many risks and their likelihood of occurrence (Simpson, 2017; Murphy et al, 2018).
Use of long-term catheterisation should be avoided entirely if there is a history of urethral trauma (urethral catheters only), cognitive impairment, where intentional or unintentional traumatic removal may be a problem or if avoidance of UTIs is a priority (Abrams et al, 2012).
Intermittent catheterisation is associated with fewer traumatic complications than an indwelling urethral catheter and is the preferable means of achieving bladder emptying. However, this may not be possible for various reasons, including patient abilities (e.g. cognitive impairment, dexterity), access to caregiver or homecare or, increasingly, patient choice (Inelman, 2007).
Complications of long-term urinary catheterisation
A 2007 Cochrane review, with a 2012 update, found insufficient evidence to offer recommendations on the best type of catheter, either urethral or suprapubic, to prevent complications (Jahn et al, 2012). Long-term catheterisation is associated with many possible complications, which are most easily considered in two groups: infectious and non-infectious (Box 3).
Catheter-associated UTIs
CAUTIs are an almost unavoidable complication of indwelling catheterisation (Inelmen et al, 2007; Simpson, 2017). Within 24 hours of catheter placement, bacteriuria is almost ubiquitous. The most important consideration in managing CAUTIs is to differentiate between asymptomatic bacteriuria and an active UTI. Regardless of the concentration of leukocytes, a patient must have active symptoms before antibiotics are administered. If a patient does develop symptoms, the UTI can be very difficult to treat without removal of the catheter, because the causative organisms usually form biofilms on the catheter. Common causative organisms include Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Candida spp. and Enterococcus spp., with E. coli being the most common by far (Gould et al, 2009). If the catheter cannot be removed, it should ideally be changed prior to starting antibiotic therapy, in order to prevent recurrence of infection. If the catheter is temporarily removed, patients can be advised to use other incontinence-management products in the interim, such as pads and disposable incontinence underwear.
Non-infectious complications
Infectious complications of long-term catheterisation have been well studied, but non-infectious complications less so. In a 2018 study of 2076 adults with an indwelling catheter, non-infectious complications were found to be five times more common than infectious complications (Saint et al, 2018). The primary non-infectious complications observed in Saint et al's (2018) study were patient discomfort, urethral trauma and incontinence (bypassing). Complications from suprapubic catheters are less common and include immediate traumatic complications from insertion as well as long-term complications of skin erosion and urine leakage around the site (Chapple et al, 2015). Blockage (or encrustation) of the catheter can also be considered a non-infectious complication. This may be caused by blood clots, but in the long term, it is more likely to be mineral deposits near the catheter tip or inside the lumen. The length of time for blockage to develop depends on the catheter material and the individual patient (Continence Product Advisor, 2019).
Choice of catheter
The Continence Product Advisor website (https://www.continenceproductadvisor.org/) provides useful information on containment products for patients and healthcare professionals. The sections on indwelling catheters and accessories provide frequently asked questions and suggestions for products, in order to avoid certain issues.
A 2005 Cochrane review, with a 2012 update, found no trials comparing permanent urethral, suprapubic or intermittent catheters, but it suggested that suprapubic catheters are preferable to urethral ones, primarily with regard to the ease of catheter replacement and avoidance of urethral complications (Niël-Weise and van den Broek, 2012). It has also been suggested that sexual activity can be more positive with suprapubic catheters, but this is not always the case (Chapple et al, 2014).
Catheters are made from different materials depending on whether they are intended for short- or long-term use. Those intended for long-term use are generally made from materials that decrease friction and tissue reaction, including silicone, silicon-elastomer coated latex and hydrophilic polymer-coated latex. Catheters designed to have antimicrobial properties, such as silver-alloy or antibiotic-impregnated ones are also available, although little is known about their long-term efficacy (Continence Product Advisor, 2019). The type of material the catheter is made of determines the maximum change interval, which is generally between 4 and 12 weeks (Inelmen et al, 2007), although policies regarding replacement vary, and research-informed data based on which a definite conclusion about the change interval can be made are limited.
Most catheters are straight-tipped; in contrast, the Coudé tip catheter has a curved tip, which may make its insertion easier in men with urinary retention caused by an enlarged prostate (Villanueva and Hemstreet, 2008). A closed drainage system (i.e. a pre-packaged sterile catheter and drainage bag) has been shown to decrease the incidence of CAUTIs (Madeo et al, 2009). However, an open-ended catheter may be helpful in patients who experience frequent catheter blockages or bypassing. Using bladder irrigation or catheter maintenance solutions may also serve to postpone catheter blockage, although this is not recommended by the US Centers for Disease Control guidelines as it may increase the risk of CAUTIs (Gould et al, 2009; Shepherd et al, 2017). Possible solutions for catheter blockage include the use of saline, sterile water, and specific prescription-only solutions of citric acid for flushing.
Various types of drainage bags are available, including those of different sizes and placements (such as the leg or abdomen), as well as catheter valves to allow draining of the bladder at socially appropriate times. Using a stabilisation device to secure the catheter to the leg can prevent discomfort from excessive movement of the catheter and may play a role in preventing CAUTIs and tension-related trauma (Darouiche et al, 2006).
Special considerations in older adults
Recent evidence supports an increased prevalence of indwelling catheterisation in older adults. Ford and Barry (2018) found that 31% of patients over 85 years of age who were receiving community nursing care had an indwelling catheter. A likely reason for this is that the indications for long-term catheterisation become more common in older adults, especially the primary indications of urinary incontinence and urinary retention. However, a study of hospitalised patients conducted over 10 years ago suggested that 25% of catheters in patients over 75 years old and 33% in those over 85 years old were unnecessary (Hampton, 2006). More recently, in a study predominantly involving catheter users over 65 years old and living at home, only half had a documented indication for their catheter use and, of those, only 35% were appropriate indications (Ford and Barry, 2018). Catheters do improve care and comfort for older patients, but their use is often a decision of convenience for both the patient and healthcare practitioner. Inappropriate catheter use has been compared to a ’one-point restraint’ and can cause pain, infection, skin breakdown and functional impairment (Inelmen et al, 2007). In fact, in a study involving older women living in the community, it was found that frail subjects with an indwelling bladder catheter were more likely to die compared to those without it (Landi et al, 2004). Nonetheless, some older people do experience a greater level of freedom and reduced social restriction when using catheters (Fowler et al, 2014).
Bacteriuria is common in all older adults, even in those without catheters, and this only increases with long-term catheterisation. UTIs are the most common infection in older adults and are associated with significant morbidity and mortality, as well as healthcare costs, all of which increase with the addition of long-term catheterisation (NICE, 2019). Additionally, the presence of asymptomatic bacteriuria increases an older adult's chances of receiving inappropriate antimicrobial therapy, which further exacerbates morbidity and mortality (Inelman, 2007).
Conclusion
With the appropriate indication for use, as well as a good understanding of appropriate care by both the patient and the healthcare team, long-term indwelling catheterisation can be a good option for patients living at home. However, it is important to ensure that steps are followed to avoid infectious and non-infectious complications, including aseptic technique, appropriate product choice and short change intervals, as well as to re-assess the indication frequently in order to avoid inappropriate use. This is especially true in the care of older adults, since the prevalence of long-term catheterisation and the risk of complications are higher in this group.