Indwelling urinary catheters: are they always necessary?
Improving cleaning practices to reduce the transmission of nosocomial infections is considered a priority in our hospitals. However a recent robust study demonstrates that around 40% of these infections are catheter-associated urinary tract infections (UTIs), and few hospitals surveyed are combating this problem aggressively. The organisms most frequently involved are normal inhabitants of the bowel, such as Escherichia coli. Pathogens form biofilms on the extraluminal and to a lesser extent intraluminal catheter surfaces where they are protected from both the effects of antimicrobials and the immune response of the host. A recent study from Canada reported that the infection rate from indwelling urinary catheters was around 5 out of 100 patients per day. Another robust study found that between 10% and 27% of catherised patients had bacteria in their urine within five days of the procedure being carried out. Comprehensive studies of elderly hospitalised patients have found that those with indwelling urinary catheters have significantly longer stays and are more likely to die in hospital. While symptomatic UTIs are the most frequent complication of catherisation, chronic pyelonephritis has been found at autopsy in approximately one third of patients who had indwelling urinary catheters, and their long-term use has been associated with bladder fibrosis and an increased risk of bladder cancer.
Of course the insertion of a urinary catheter can be a medical necessity, and in this case careful attention should be given to aseptic insertion techniques as well as the choice of device [see this issue of IHE, page 6]. However it would be prudent, given the increased morbidity and mortality associated with the procedure, to question, prior to each insertion, whether it is really necessary. A concerted effort should also be made to limit the duration of catheterisation should it be medically indicated. Yet a multi-centre study in the US found that in around 30% of cases the attending physician did not know if his/her hospitalised patient had an indwelling urinary catheter or not. In 31% of cases the catheters were found to be unnecessary.
A plethora of other studies has shown that, particularly in elderly patients, indwelling catheters are frequently used for the benefit of over-worked healthcare personnel rather than because their use is medically indicated. The most common reasons reported for unnecessary catheterisation are patient incontinence, cognitive impairment and impaired mobility.
It is indeed apalling to think that patients