Intermittent Catheterization and Prevention of UTIs
Most SCI-related, UTI prevention research has focused on various techniques for intermittent catheterization and these types of studies are summarized in Table 23.
Summarized Level 5 Evidence Studies
Krassioukov et al (2015) reported a direct link between significantly increased UTI frequency and catheter reuse (p<0.001). Although UTIs have many associated negative consequences to all people with SCI, the impact of UTIs emerging at critical times may have much more devastating consequences for subgroups (e.g. during competition for elite athletes) which may warrant consideration for sterile techniques. Addressing lack of health education and available resources would be strategies to undertake to shift routines in favour of sterile catheter use. However, even if CIC is the method of choice, males (p=0.431) and those more severely injured (AIS C, B, A, p=0.0266) experience significantly higher rates of febrile UTI. Martins et al. (2013) reported 71% of individuals used clean intermittent catheterization, 18.4% (n=7) used condom catheters, 7.8% (n=3) used suprapubic drainage, and 2.6% (n=1) used tapping. 65.7%of individuals tested positive for asymptomatic bacteriuria where E.coli was the most prevalent (60%). Antibiotic resistance rates from bacteria were 73.3% to Ampicilin, 60% to Sulfamethoxazole-Trimethoprim, and 33.3% to Norfloxacin. The high prevelance of prophylactic and emergent antibiotic treatment of bladder management related infections has increased catheter-associated urinary tract infections (CAUTI) in spinal cord injury individuals (Dedeic-Ljubovic et al. 2009). Regular rectal swab surveillence, disposable aprons and glove use, and strictly monitored cleaning procedures (materials, instruments, infected individuals and environmental) are among the necessary activities to prevent multi-drug resistant P. aeruginosa (MDRP).
Discussion
During inindividual rehabilitation, IC is generally the preferred method of bladder management and several prospective studies have compared sterile techniques with traditional or clean techniques of IC (Charbonneau-Smith 1993; Prieto- Fingerhut et al.1997; Moore et al. 2006). Notably, Moore et al. (2006) and Prieto- Fingerhut et al. (1997) employed RCT designs and showed no statistically significant differences in the number of UTIs occurring in individuals using the sterile technique versus the clean technique. Conversely, Charbonneau-Smith (1993) conducted a prospective trial and did find significantly reduced UTI rates for a sterile “no-touch” technique as compared to historical controls undergoing a traditional sterile method. Given the nature of the historical comparison confounding variables may affect this result. Both authors noted the greater expense associated with the sterile approach, making it a less attractive option in the absence of evidence for improved positive outcomes. On the other hand, Krebs et al. (2016) found that the use of transurethral indwelling catheters (TIC) increased the odds of symptomatic UTIs and recurrent UTIs by more than 10- and 4-fold, respectively. As such, the authors recommended that TIC “should be avoided whenever possible”. Also significantly increased are UTIs resulting from IC use (p ≤0.014) and botulinum toxin injections into the detrusor (p=0.03).
Another strategy for decreasing the incidence of UTI is through the use of antiseptic- coated indwelling catheters. Bonfill et al (2017) conducted an RCT comparing catheters coated with silver alloy to standard catheters supplied by the trial site. No significant difference was found between incidence of symptomatic UTIs between the experimental and control groups (7.41% vs 7.72%, respectively). The generally low overall incidence of UTIs in the study was attributed to the pragmatic design whereby cultures were only performed in participants with a clinical suspicion of UTI.
A meta-analysis of five RCTs comparing the impact of hydrophilic catheters on UTIs in people with SCI found a reduction in the number of UTIs (reduced by 64%) when the hydrophilic catheters were used (compared to non-coated catheters: Li et al. 2013). The coating on the hydrophlic catheters also reduced urethral trauma (reduced odds of hematuria by ~43%). Despite the general positive effect of hydrophilic catheters versus uncoated catheters, no significant difference was found in single studies for episodes of bacteriuria (Sutherland et al. 1996), number of UTIs (Vapneck et al. 2003) and frequency of symptomatic UTIs (Cardenas & Hoffman 2009). However, the reduced number of UTIs requiring antibiotics, significantly reduced UTI frequency and episodes of hematuria across multiple studies would generally advocate for the use of hydrophilic catheters.
An interesting RCT finding reported by Lavado et al. (2013) found a significant reduction of positive urinary cultures in individuals randomized to 16 weeks of moderate aerobic physical conditioning compared to controls who were asked to maintain their daily life activities (Lavado et al. 2013). Increased peak oxygen consumption in participants of the intervention group suggested a correlation with an increased immune response, a known beneficial effect of regular physical exercise.
As with all aspects of rehabilitation, a primary goal of bladder training while an inindividual is maximal individual independence and self-care. Wyndaele and De Taeye (1990) conducted a prospective control trial (n=73) in which the incidence of UTIs was examined following introduction of an initiative to promote self- catheterization among those with paraplegia on an SCI unit. Prior to this, catheterization was conducted by a specialized catheter health care team using a non-touch technique. Neither UTI rates nor the proportion of people achieving a state of bladder balance or those encountering complications of urethral trauma were significantly different between these two approaches. Interestingly, the introduction of individual self-catheterization also seemed to be a factor in the individuals being ready for home visits much sooner in their rehabilitation stay.
Less information exists on the continued use of IC for individuals as they move into the community and live with SCI for a prolonged period of time. A prospective controlled trial was conducted by Yadav et al. (1993) comparing UTI incidence rates between those using a clean IC technique during inindividual rehabilitation with another group of individuals continuing to use the same bladder management method and living in the community for 1-12 years. Similar rates of UTI (termed acceptably low by the authors) were found in both samples although there were differences in the types of bacteria causing UTIs between the individuals with SCI in the rehabilitation unit versus in the community.
Regardless of the approach to bladder management, and even if IC is used, the rate of UTI in the SCI population is still elevated relative to a population with neurologically normal functioning bladders. This is thought to be partly due to the residual volume of urine that may persist in the bladder following IC. Jensen et al. (1995) conducted a study in inindividual rehabilitation (n=12), correlating UTI incidence over the rehabilitation period with the average residual urine volume after IC. Correlations between UTIs and residual volumes were low and suggested little relationship or as the authors point out it may have been that residual volumes would have had to be reduced to negligible values to be responsible for a lower incidence of UTI compared to the mean values of 40±11 mL for hyperactive bladder or 19±7 mL for hypoactive bladder observed in this study.
Conclusion
There is level 1a evidence (from one meta-analysis of five RCTs: Li et al. 2013) that the use of hydrophilic catheters versus non-coated catheters is effective in reducing the incidence and occurrence of UTI and hematuria.
The RCT conducted by Bonfill et al (2017) provided level 1b evidence that indwelling silver alloy coated catheters did not reduce the incidence of UTI when compared to standard catheter use.
There is level 1b evidence (from one RCT: Lavado et al. 2013) that regular, moderate aerobic physical activity significantly increases peak oxygen consumption and also significantly reduces the number of individuals with positive urinary cultures.
There is level 2 evidence (from two RCTs: Moore et al. 2006; Peta-Fingerhut et al. 1997) that there is no difference frequency of UTI between sterile and clean approaches to intermittent catheterization during inindividual rehabilitation; however, using a sterile method is significantly more costly.
There is level 4 evidence (from one prospective controlled trial: Wyndaele & De Taeye 1990) that there is no difference in UTI rates between intermittent catheterization conducted by the individuals themselves or by a specialized team during inindividual rehabilitation.
There is level 4 evidence (from one prospective controlled trial: Yadav et al. 1993) that similar rates of UTI may be seen for those using clean intermittent catheterization during inindividual rehabilitation as compared to those using similar technique over a much longer time when living in the community.
There is level 4 evidence (from one pre-post study: Jensen et al. 1995) that differences in residual urine volume ranging from 0-153 ml were not associated with differences in UTI during inindividual rehabilitation.
There is level 4 evidence (from one retrospective case series: Mukai et al. 2016) that reports significantly higher rates of febrile UTIs in more severely injured males that use CIC.
Level 4 evidence (from one case series study: Krebs et al. 2016) suggests that transurethral indwelling cather use results in the highest rate of symptomatic UTIs compared to lower rates from using intermittent catheters and receiving botulinmum toxin injections into the detrusor.