Endoscope Reprocessing: Update on Controversial Issues

Novel and effective disposable device that provides 2-way protection to the duodenoscope from microbial contamination

BACKGROUND AND AIMS

Duodenoscope contamination is associated with notable patient morbidity and mortality and can occur despite high-level disinfection protocols, requiring a solution that protects against contamination of the endoscope in the first place.

METHODS

We assessed a newly cleared, single-use device to seal the distal end of duodenoscopes while preserving optics and other endoscope functionality and tested its ability to protect against contamination using dye immersion tests and microbial inoculation.

RESULTS

Dye immersion tests revealed a complete seal with no leakage. Rigorous microbial challenge tests showed the device can both protect against contamination of the endoscope by external microbes ("outside-in" protection) and shield instruments from contact with pre-existing microbial biofilm on or around the elevator that may have survived reprocessing ("inside-out" protection). Optical and mechanical performance of the endoscope was not compromised by the addition of the device.

CONCLUSIONS

The results show that this disposable device provides 2-way protection to the duodenoscope from microbial contamination, without the potential for disrupting current equipment, technique, and workflow.

Cost Comparison of Single-Use Versus Reusable Bronchoscopes Used for Percutaneous Dilatational Tracheostomy

BACKGROUND

Both single-use and reusable bronchoscopes are suitable for percutaneous dilatational tracheostomy (PDT) to visualise the trachea during the insertion process. To determine the least costly option, the price of single-use bronchoscopes must be weighed against the estimated average cost of a bronchoscopy with reusable equipment. In the latter case, the acquisition cost must be spread over the equipment's useful life and other relevant costs, such as reprocessing and repair, must be included.

OBJECTIVE

This study aimed to calculate the cost of using single-use or reusable bronchoscopes per PDT procedure.

METHODS

A systematic literature search was conducted to identify studies comparing the costs of reusable and single-use bronchoscopes for PDT. Inclusion criteria were articles assessing the cost of single-use or reusable bronchoscopes, and where costs were divided into acquisition, reprocessing, and repair costs. A questionnaire regarding repair rates and costs for reusable bronchoscopes was sent to 366 hospitals in the US, UK, and Germany to supplement the identified literature.

RESULTS

Eleven studies met the inclusion criteria. Ninety-nine completed responses were received, of which 31 hospitals used reusable equipment for PDT. Literature research revealed an average acquisition cost of $US135 (SD 152) and reprocessing cost of $US123 (SD 128). Additionally, a combination of data from the literature and the questionnaires gave a repair cost per use of $US148 (SD 242), resulting in a total average cost of $US406 for reusable bronchoscopes and $US249 (SD 36) for single-use bronchoscopes per PDT procedure. Thus, the incremental cost per use of a reusable bronchoscope compared with a single-use bronchoscope was $US157.

CONCLUSIONS

We conclude that significant savings can be made by using single-use bronchoscopes to guide PDT in preference to reusable bronchoscopes. Results depend on hospital setting, the reprocessing procedures, annual bronchoscope procedures, individual repair cost, and repair rates.

An update on gastrointestinal endoscopy-associated infections and their contributing factors

INTRODUCTION

During clinical use, gastrointestinal endoscopes are grossly contaminated with patient's native flora. These endoscopes undergo reprocessing to prevent infectious transmission upon future use. Endoscopy-associated infections and outbreaks have been reported, with a recent focus on the transmission of multi-drug resistant organisms. This review aims to provide an update on endoscopy-associated infections, and the factors contributing to their occurrence.

METHODS

PubMed, ScienceDirect, and CINAHL were searched for articles describing gastrointestinal endoscopy-associated infections and outbreaks published from 2008 to 2018. Factors contributing to their occurrence, and the outcomes of each outbreak were also examined.

RESULTS

This review found 18 articles, 16 of which described duodenoscope-associated infections, and the remaining two described colonoscope- and gastroscope-associated infection respectively. Outbreaks were reported from the United States, France, China, Germany, the Netherlands and the United Kingdom. The causative organisms reported were Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Salmonella enteritidis.

CONCLUSIONS

A number of factors, including lapses in reprocessing, biofilm formation, endoscope design issues and endoscope damage, contribute to gastrointestinal endoscopy associated infection. Methods of improving endoscope reprocessing, screening for contamination and evaluating endoscope damage may be vital to preventing future infections and outbreaks.

The validity of adenosine triphosphate measurement in detecting endoscope contamination

BACKGROUND

Endoscopic procedures are vital to gastrointestinal disease diagnosis and management, but risk infection transmission. In Australia, endoscopes undergo monthly-to-quarterly microbiological testing, to prevent patient infection. Endoscopes are used more frequently, meaning contamination may not be detected by this surveillance before infection transmission occurs.

AIM

To evaluate the use of adenosine triphosphate (ATP) measurement, alongside standard microbiological cultures, in detecting endoscope contamination before high-level disinfection. Using these results, we also aimed to confirm the efficacy of manual cleaning in reducing levels of ATP and cfu/mL.

METHODS

Seventeen in-clinical-use gastroscopes and 24 in-clinical-use colonoscopes from the Liverpool Hospital Endoscopy unit were sampled across three separate cleaning stages before high-level disinfection. Colony counts and ATP measurements were then performed on these samples.

FINDINGS

The correlation between the cfu/mL and RLU of samples collected from colonoscopes was 0.497 (95% confidence interval: 0.28-0.66; P < 0.0001). The correlation between cfu/mL and RLU for samples collected from gastroscopes was 0.377 (0.08-0.61; P = 0.0138). RLU and cfu/mL values were shown to fall significantly (P < 0.005) following precleaning and manual cleaning.

CONCLUSION

There was a significant correlation between ATP and cfu/mL measured from samples collected before high-level disinfection. Precleaning and manual cleaning were shown to reduce ATP and microbiological load significantly. ATP measurement can be performed within minutes with little training and produces results that are easy to interpret. These findings warrant further research on the utility of ATP measurement as a screening tool for detecting endoscope contamination after high-level disinfection.