Management of short-term indwelling urethral catheters to prevent urinary tract infections.

BACKGROUND
This systematic review updates a previous review published in 2000. The objective of this review was to present the best available evidence relating to the prevention of catheter-associated urinary tract infections (UTI).


SELECTION CRITERIA
This review considered randomised controlled trials (RCTs) of adult patients with short-term urethral catheters. In the absence of RCTs, other research designs such as non-randomised controlled trials and before and after studies were considered for inclusion. Interventions of interest were those related to the prevention of catheter-related UTI and included: sterile versus non-sterile insertion technique, special coatings to catheters versus standard non-coated catheters, the use of flush solutions, the use of solutions added to urinary drainage bag, maintenance of a closed urinary drainage circuit, the use of antireflux valves, antibiotic creams applied to the external meatus-catheter interface, meatal care regimens, education programs, and changed care delivery practices. This review was limited to short-term urethral catheters, and so studies evaluating long-term or suprapubic catheters were excluded. The primary outcome of interest was the difference in the rates of UTI between experimental intervention and the control.


SEARCH STRATEGY
The search included both published and unpublished studies with an initial limited search of MEDLINE and CINAHL databases undertaken to identify key words contained in the title or abstract, and index terms used to describe relevant interventions. A second extensive search used all identified key words and index terms. The third step included a search of the reference lists and bibliographies of relevant articles. The databases searched included: CINAHL, MEDLINE, Current Contents, Cochrane Library, Expanded Academic Index, and Embase. The Dissertation Abstracts International database was searched for unpublished studies.


ASSESSMENT OF METHODOLOGICAL QUALITY
Methodological quality was assessed using a standardised checklist. Critical appraisal and data extraction were conducted by two independent reviewers; discrepancies were addressed through discussion with a third reviewer as required.


RESULTS
There was no significant difference in infection rate using either sterile surgical or non-sterile insertion technique. The use of water for cleansing prior to catheter insertion was recommended. There was no additional benefit from specific meatal care other than standard daily personal hygiene and removal of debris. Infection rates were similar for both latex and silicone catheters. Comparisons between silver and Teflon coating clearly favoured the silver alloy coating. The use of a complex closed drainage system in the intensive care environment did not confer any additional benefit. Studies comparing types of junction seals and use of junction seals either prior to or following catheterisation found no clear benefit from using either preconnected sealed systems or sealed systems with the addition of silver releasing devices. Neither the addition of chlorhexidine nor hydrogen peroxide to the drainage bag was found to be effective at reducing UTI rates. The findings indicated there was a higher incidence of bacteriuria associated with Foley catheters compared with intermittent catheterisation (P < 0.025). A single RCT examined the effect on UTI rates of routine bag changes against no routine bag change. Routine bag changes were not advantageous in reducing the risk of infection.


CONCLUSIONS
Current RCT evidence suggests the use of a surgical sterile catheterisation technique is not required, and that tap water is sufficient for cleaning genitalia. Following insertion, daily hygiene around the meatal area is as effective as catheter toilets; and catheters impregnated with silver may reduce the incidence of catheter associated bacteriuria. Sealed (e.g. taped, presealed) drainage systems should not be relied upon as the sole mechanism for prevention of bacteriuria. The addition of antibacterial solutions to drainage bags and the routine change of drainage bags had no effect on catheter associated infection. However, most of the recommendations arising from this review were based on single studies, often with limited numbers of participants. There is an urgent need to replicate these studies in other clinical settings.