Double high-level disinfection versus liquid chemical sterilization for reprocessing of duodenoscopes used for ERCP: a prospective randomized study

Assessment of the Learning Curve for a Single-Use Disposable Duodenoscope

BACKGROUND AND AIMS

In response to documented duodenoscope-related infectious outbreaks of multidrug-resistant organisms, the Food and Drug Administration has recommended a transition to duodenoscopes with innovative designs, including duodenoscopes with disposable components or fully disposable duodenoscopes. We aim to characterize the learning curve (LC) for a single-use disposable duodenoscope.

METHODS

We performed a retrospective analysis of a prospectively collected database from 31 patients who underwent ERCP by a single, experienced operator using the EXALT Model D® (Boston Scientific, Marlborough) disposable duodenoscope at a single tertiary referral center. The LC for this device was described by the number of cases needed to achieve proficiency using cumulative sum (CUSUM) analysis. Number of attempts to cannulate and time to cannulate the desired duct were assessed as separate endpoints. The overall mean number of attempts and overall mean time to cannulation were used as the target values in the respective CUSUM analyses. Proficiency was defined as the number of procedures where an inflection point was reached in the CUSUM graph. This observation indicates improving operator performance as shown by a decrease in the number of attempts and shortening of cannulation time after the defined number of procedures.

RESULTS

Overall, 31 patients underwent ERCP using the EXALT Model D disposable duodenoscope by a single experienced endoscopist. 6 (19%) patients had a native papilla and the majority of these procedures were classified as ASGE complexity level 2 or above. The procedure was completed using solely the disposable duodenoscope in 27 patients (87%), while a reusable duodenoscope was required for procedure completion in 4 patients (13%). The cross-overs were distributed evenly across the performance period. Procedure-related adverse events included: post-ERCP pancreatitis (3%), bleeding (3%) and no perforations. In the analyses of both endpoints, an inflection of the CUSUM curves is achieved at 10 cases, indicating sustained reduction of cannulation attempts and time to cannulation.

CONCLUSION

Among experienced pancreaticobiliary endoscopists, approximately 10 ERCPs is the threshold whereby procedure-related factors including cannulation success and procedural time improves. Procedure-related adverse events are consistent with those expected with reusable duodenoscopes. The need to cross-over from single-use duodenoscope to reusable duodenoscope did not appear to be related to the learning curve, as they were evenly distributed across the study period. These results can be used to guide adoption of single-use duodenoscopes into clinical practice.

Reprocessing semicritical items: An overview and an update on the shift from HLD to sterilization for endoscopes

BACKGROUND

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (e.g., gastrointestinal endoscopes, endocavitary probes). Such medical devices require minimally high-level disinfection.

METHODS

Analyze the methods used to reprocess semicritical medical devices and identify methods and new technologies to reduce the risk of infection.

RESULTS

The reprocessing methods for semicritical medical devices is described as well as a shift from high-level disinfection to sterilization for lumened endoscopes.

CONCLUSIONS

Strict adherence to current guidelines and transition to sterilization for endoscopes is required as more outbreaks have been linked to inadequately disinfected endoscopes and other semicritical items than any other reusable medical devices.

Single-use duodenoscopes compared with reusable duodenoscopes in patients carrying multidrug-resistant microorganisms: a break-even cost analysis

Background and study aims  Single-use duodenoscopes can prevent transmission of microorganisms through contaminated reusable duodenoscopes. Concerns regarding their economic and environmental impact impede the transition to single-use duodenoscopes. This study investigated the costs associated with two scenarios in which single-use duodenoscopes are used in patients carrying multidrug-resistant microorganisms (MDROs). Methods  Break-even costs for single-use duodenoscopes were calculated for two scenarios in which patients were screened for MDRO carriage before undergoing endoscopic retrograde cholangiopancreatography (ERCP). Only direct costs related to the endoscopy were taken into consideration. In Scenario 1, patients were screened through microbiological culturing with a lag time in receiving the test result. In Scenario 2, screening was performed using GeneXpert analysis providing a rapid read-out. Calculations were performed using data from a Dutch tertiary care center and also with US healthcare data. Results  In the Dutch situation, single-use duodenoscopes needed to be priced at a maximum of € 140 to € 250 to break-even. In the US analyses, break-even costs varied widely, depending on the duodenoscope-associated infection costs used, ERCP volume, and infection risk. The break-even costs in Scenario 1 ranged between $78.21 and $2,747.54 and in Scenario 2, between $248.89 and $2,209.23. Conclusions  This study showed that a crossover scenario in which single-use duodenoscopes are only used in patients carrying MDROs could be an economically viable alternative to a complete transition to single-use duodenoscopes. In the Dutch setting, single-use duodenoscopes need to be priced much lower than in the United States to reach a per-procedure cost that is comparable with a scenario using reusable duodenoscopes exclusively.

Effect of an automated flexible endoscope channel brushing system on improving reprocessing quality: a randomized controlled study

BACKGROUND

Qualified reprocessing, of which meticulous channel brushing is the most crucial step, is essential for prevention and control of endoscopy-associated infections. However, channel brushing is often omitted in practice. This study aimed to evaluate the effect of an automated flexible endoscope channel brushing system (AECBS) on improving the quality of endoscope reprocessing.

METHODS

This prospective, randomized controlled study was conducted between 24 November 2021 and 22 January 2022 at Renmin Hospital of Wuhan University, China. Eligible endoscopes were randomly allocated to the auto group (channels brushed by AECBS) or the manual group (channels brushed manually), with sampling and culturing after high-level disinfection and drying. The primary end point was the proportion of endoscopes with positive cultures.

RESULTS

204 endoscopes in the auto group and 205 in the manual group were analyzed. The proportion of endoscopes with positive cultures was significantly lower in the auto group (15.2 % [95 %CI 10.7 %-21.0 %]) than in the manual group (23.4 % [95 %CI 17.9 %-29.9 %]).

CONCLUSIONS

AECBS could effectively reduce bioburden and improve reprocessing quality of gastroscopes and colonoscopes. AECBS has the potential to replace manual brushing and lower the risk of endoscopy-associated infections, providing a new option for the optimization of reprocessing.

Bacterial contamination and organic residue after reprocessing in duodenoscopes with disposable distal caps compared with duodenoscopes with fixed distal caps: a randomized trial

BACKGROUND AND AIMS

Newly designed duodenoscopes with disposable distal caps have been developed for better cleaning and preprocessing to reduce the risk of bacterial contamination (BC). We compared BC and organic residue of duodenoscopes with disposable distal caps and duodenoscopes with fixed distal caps after manual cleaning and high-level disinfection (HLD).

METHODS

Four hundred duodenoscopes were randomized into group A (fixed distal caps, n = 200) and group B (disposable distal caps, n = 200). After manual cleaning, samples from the elevator were submitted for culture. An adenosine triphosphate (ATP) test was performed for organic residue evaluation. Based on our previous data, ATP < 40 relative light units (RLUs) had 100% sensitivity with 100% negative predictive value to confirm no BC after reprocessing.

RESULTS

After manual cleaning, group A had a higher BC rate (14% vs 7%, P = .02), a higher proportion of duodenoscopes with ATP ≥ 40 RLUs (73.5% vs 57%, P = .001), and a higher mean of ATP level (226.6 vs 82.0 RLUs, P < .001) compared with group B. After HLD, the proportion of potential BC (ATP ≥ 40 RLUs) in group A was 2.7 times higher than group B (4% vs 1.5%, P = .13). Mean ATP level after HLD in the 2 groups was significantly lower than before the HLD procedure (group A, 24.2 vs 226.6 RLUs [P < .001]; group B, 20.4 vs 82.0 RLUs [P < .001], respectively).

CONCLUSIONS

After manual cleaning, duodenoscopes with disposable distal caps had significantly lower BC and organic residue than duodenoscopes with fixed distal caps. Only a few duodenoscopes from each group did not pass the ATP threshold after HLD.

Contamination Rates in Duodenoscopes Reprocessed Using Enhanced Surveillance and Reprocessing Techniques: A Systematic Review and Meta-Analysis

Background/Aims

Multiple outbreaks of multidrug-resistant organisms have been reported worldwide due to contaminated duodenoscopes. In 2015, the United States Food and Drug Administration recommended the following supplemental enhanced surveillance and reprocessing techniques (ESRT) to improve duodenoscope disinfection: (1) microbiological culture, (2) ethylene oxide sterilization, (3) liquid chemical sterilant processing system, and (4) double high-level disinfection. A systematic review and meta-analysis was performed to assess the impact of ESRT on the contamination rates.

Methods

A thorough and systematic search was performed across several databases and conference proceedings from inception until January 2021, and all studies reporting the effectiveness of various ESRTs were identified. The pooled contamination rates of post-ESRT duodenoscopes were estimated using the random effects model.

Results

A total of seven studies using various ESRTs were incorporated in the analysis, which included a total of 9,084 post-ESRT duodenoscope cultures. The pooled contamination rate of the post-ESRT duodenoscope was 5% (95% confidence interval [CI]: 2.3%–10.8%, inconsistency index [I²]=97.97%). Pooled contamination rates for high-risk organisms were 0.8% (95% CI: 0.2%–2.7%, I²=94.96).

Conclusions

While ESRT may improve the disinfection process, a post-ESRT contamination rate of 5% is not negligible. Ongoing efforts to mitigate the rate of contamination by improving disinfection techniques and innovations in duodenoscope design to improve safety are warranted.

Current State and Future of Infection Prevention in Endoscopy

Gastrointestinal (GI) endoscopy units tend to be busy environments in which numerous categories of staff provide moderately complex procedural care to high volumes of patients. The prevention of infections of both patients and staff is a never-ending endeavor for both inpatient and outpatient environments. Necessary considerations must address patient-to-staff, staff-to-patient, environmental, and device-related transmission of infection. In addition to the typical environmental and interpersonal infection risks present in all medical environments, the major concern within the endoscopy suite relates to contamination and potential transmission via reusable devices and endoscopes. Our understanding of this ever-present issue has evolved over time and has become a major focus of scrutiny in the past 5 years. This significant problem has stimulated guidance and ingenuity by regulators, investigators, and industry. Most recently, the COVID-19 pandemic of 2020 to 21 has also added significant burdens to our infection control efforts in gastrointestinal endoscopy.

Recent Advances in Endoscope Disinfection: Where Do We Stand in the COVID era?

Over 16 million cases worldwide, severe acute respiratory syndrome coronavirus 2 has profoundly affected healthcare as we know it. Given reports of gastrointestinal involvement and viral shedding in the stool, it is unsurprising there are concerns that endoscopic equipment may be a potential vector of viral transmission. Here, we provide an overview of existing practices for endoscope reprocessing, recent developments in the field, and challenges in the COVID-19 environment. Current multi-society guidelines do not advise any change to endoscope disinfection protocols but emphasize strict adherence to recommended practices. However, endoscopy reprocessing staff may benefit from supplemental personal protective equipment measures, especially in high risk situations. Because thorough endoscope reprocessing is highly operator dependent, adequate training of personnel is critical for proper manual cleaning and disinfection of endoscopes that have potential to harbor virus. Bacterial contamination of duodenoscopes has caused outbreaks of infection from multidrug-resistant organisms, highlighting vulnerable areas. The emphasis of current studies is on optimization of disinfection and drying, minimization of simethicone use, and on quality control of endoscope reprocessing with sampling and microbiological culturing. Recent advances include novel approaches to endoscope sterilization, infection barrier methods, and design of partially or fully disposable duodenoscopes. Overall, the available data indicate that, when correctly executed, current reprocessing practices are sufficient in preventing SARS-COV-2 transmission.

Duodenoscope-associated infection prevention: A call for evidence-based decision making

Background  Recent outbreaks of duodenoscope-associated multidrug-resistant organisms (MDROs) have brought attention to the infection risk from procedures performed with duodenoscopes. Prior to these MDRO outbreaks, procedures with duodenoscopes were considered safe and low risk for exogenous infection transmission, provided they were performed in strict accordance with manufacturer instructions for use and multisociety reprocessing guidelines. The attention and efforts of the scientific community, regulatory agencies, and the device industry have deepened our understanding of factors responsible for suboptimal outcomes. These include instrument design, reprocessing practices, and surveillance strategies for detecting patient and instrument colonization. Various investigations have made it clear that current reprocessing methods fail to consistently deliver a pathogen-free instrument. The magnitude of infection transmission has been underreported due to several factors. These include the types of organisms responsible for infection, clinical signs presenting in sites distant from ERCP inoculation, and long latency from the time of acquisition to infection. Healthcare providers remain hampered by the ill-defined infectious risk innate to the current instrument design, contradictory information and guidance, and limited evidence-based interventions or reprocessing modifications that reduce risk. Therefore, the objectives of this narrative review included identifying outbreaks described in the peer-reviewed literature and comparing the findings with infections reported elsewhere. Search strategies included accessing peer-reviewed articles, governmental databases, abstracts for scientific conferences, and media reports describing outbreaks. This review summarizes current knowledge, highlights gaps in traditional sources of evidence, and explores opportunities to improve our understanding of actual risk and evidence-based approaches to mitigate risk.