An effective evidence‐based cleaning method for the safe reuse of intermittent urinary catheters: In vitro testing

Abstract

Aims To determine a safe bactericidal cleaning method that does not damage urethral catheters used for intermittent catheterization. In some countries, single‐use catheters are the norm; in others, the reuse of catheters is common depending on health insurance, personal preference, or individual concerns about the environment. However, no recent study of cleaning methods has been published to provide evidence for the safe reuse of catheters. Methods Using advanced microbiological methods, a laboratory study of eight cleaning methods was conducted. Sections of uncoated polyvinylchloride (PVC) catheters were exposed to bacterial uropathogens in physiologically correct artificial urine media then tested with a range of heat, chemical, and mechanical cleaning methods. Analysis of culturable and viable but nonculturable (VBNC) bacteria was done and direct microscopy was used. Descriptive statistics were used to compare values. Results Heat treatments, although effective, resulted in catheter surface breakdown and damage. Ultrasonic cleaning and vinegar showed evidence of VBNC populations indicating the methods were bacteriostatic. Detergent and water wash followed by immersion in a commercially available 0.6% sodium hypochlorite solution and 16.5% sodium chloride (diluted Milton) gave consistent bactericidal results and no visible catheter damage. Conclusions Combined mechanical and chemical treatment of a detergent and water wash followed by immersion in diluted Milton (the “Milton Method”) provided consistent and effective cleaning of uncoated PVC catheters, showing bactericidal action for all uropathogens tested after repeated exposure. If found safe in clinical testing, this method could increase the reuse of catheters, reduce plastic waste in the environment, reduce cost, and increase patient choice.

The microbiological and physical properties of catheters for intermittent catheterization: A systematic review on the impact of reuse and cleaning methods

“…The literature search yielded 9613 articles. After eliminating duplicates and reviewing the remaining titles and abstracts (Figure 1), a total of 12 studies 7,16,19,21,[28][29][30][31][32][33][34][35] that included outcomes of catheter bacterial colonization or changes in physical properties following cleaning of catheters for reuse were eligible and included (Table 1).…”

“…Among heat-based cleaning methods the microwave treatment (n = 6) 19,21,29,[31][32][33] was the most commonly used followed by boiling (n = 1) 19 and steam sterilization (n = 1). 19 Overall, it was generally agreed that upon increasing the length of microwaving time resulted in a reduction in colony counts. Rubber catheters were reportedly able to be sterilized by microwave treatment 29,32,33 , but none of these studies fully analyzed the impact on the structural integrity of the catheters.…”

“…Of the 12 studies included in this systematic review, nine were analytical experimental studies 19,[28][29][30][31][32][33][34][35] , one of which was also partially a cohort study. 30 The remaining were either a cohort 16 or cross-sectional 21 study and a case series.…”

“…7 Based on presently published literature, multiple cleaning methods have been tested and proposed in order to decontaminate catheters including heat (microwave 19,21,29,[31][32][33]35 , steam 19 , or boiling 19 ), mechanical (ultrasonic 19 , detergent and rinsing 19,28,32,35 ), chemical (bleach 34 , hydrogen peroxide 28,34 , betadine 34 , vinegar 19,28 , Milton solution 19 , Savlon solution 7 , 70% alcohol 31 ), and other (photocatalytic 30 , mixture of methods 16 or combination of two methods 19,35 ). The majority of these studies (n = 10) 16,19,[28][29][30][31][32][33][34][35] used culture analysis as a microbiological technique to assess for the presence of bacteria. Several studies (n = 7) 7,16,19,21,29,31,32 examined the impact of cleaning methods on physical properties of catheters, however only a minority (n = 4)…”

“…The majority of these studies (n = 10) 16,19,[28][29][30][31][32][33][34][35] used culture analysis as a microbiological technique to assess for the presence of bacteria. Several studies (n = 7) 7,16,19,21,29,31,32 examined the impact of cleaning methods on physical properties of catheters, however only a minority (n = 4) 7,16,19,31 examined the microscopic physical properties of the catheter. All 12 studies were grouped based on the type of cleaning methods analyzed, which included the following categories: heat-based, mechanical-based, chemical, combined and others.…”