Safely reprocessing duodenoscopes: current evidence and future directions

Impact of Duodenoscope Reprocessing Factors on Duodenoscope Contamination: A Retrospective Observational Study

BACKGROUND

Despite adherence to reprocessing protocols, duodenoscopes often remain contaminated, highlighting significant knowledge gaps in reprocessing efficiency.

AIM

This study aims to identify risk factors in duodenoscope reprocessing procedures affecting contamination rates.

METHODS

We included cultures from Pentax ED34-i10T2 duodenoscopes collected between February 2022 and December 2023. Contamination was determined by the presence of microorganisms of gut or oral origin (MGO). Data on duodenoscope use, reprocessing lead times and personnel were retrieved from electronic medical records. Risk factors were derived from reprocessing guidelines and literature. These included a delay over 30 minutes in initiating manual cleaning, manual cleaning duration of five minutes or less, drying time under 90 minutes, personnel reprocessing frequency, and storage exceeding seven days. A logistic mixed-effects model evaluated these factors' impact on duodenoscope contamination.

FINDINGS

Out of 307 duodenoscope cultures, 58 (18.9%) were contaminated with MGO. Throughout the study period, the duodenoscopes underwent 1296 reprocessing cycles. Manual cleaning times of five minutes or less significantly increased contamination odds (aOR = 1.61, 95%CI:1.10-2.34, p=0.01). Interestingly, increased usage of a duodenoscope was associated with reduced odds of contamination (aOR= 0.80, 95%CI:0.64-0.995, p=0.045). Other studied risks showed no clear association with contamination rates.

CONCLUSION

Manual cleaning times of five minutes or less increased the odds of contamination with MGO. Delays in reprocessing initiation and incomplete drying, traditionally considered as risk factors, were not associated with an increased risk of contamination in this study. Future research should explore whether enhanced surveillance of reprocessing times can mitigate duodenoscope contamination.

Bacterial bioburden of duodenoscope elevator mechanism in different reprocessing stages

Over the past decade, infections linked to duodenoscopes have become a significant concern, primarily due to the intricate design of the elevator mechanism. Currently, there is limited evidence regarding the bacterial contamination level of the elevator mechanism after clinical use and throughout its various reprocessing stages. This study utilized the swab culture technique to examine the bacterial contamination on the duodenoscope elevator mechanism after clinical use and after 3 reprocessing stages at a Center of tertiary hospital. Our findings revealed severe bacterial contamination after clinical usage, emphasizing that the effectiveness of manual cleaning greatly influences the subsequent high-level disinfection quality.

Randomized Trial of Prophylactic Antibiotics for Endoscopic Retrograde Cholangiopancreatography in Patients With Biliary Obstruction

INTRODUCTION

The incidence of postendoscopic retrograde cholangiopancreatography (ERCP) infections is reported to be up to 18% in patients with biliary obstruction. Antibiotic prophylaxis may reduce the risk of infectious complications after ERCP; however, the clinical value of prophylactic antibiotics in ERCP remains controversial.

METHODS

We conducted a double-blind, placebo-controlled, randomized trial to investigate whether the use of prophylactic antibiotics would reduce infectious complications after ERCP in patients with biliary obstruction. We randomly assigned patients in a 1:1 ratio to receive either a single dose of 1 g intravenous cefoxitin or normal saline as a placebo 30 minutes before undergoing ERCP. The primary outcome was the incidence of infectious complications after ERCP.

RESULTS

We enrolled 378 patients, and 189 patients were assigned to each group. The risk of infectious complications after ERCP was 2.8% (5 of 176 patients) in the antibiotic prophylaxis group and 9.8% (17 of 173 patients) in the placebo group (risk ratio, 0.29; 95% confidence interval [CI], 0.11-0.74, P = 0.0073). The incidence rates of bacteremia were 2.3% (4 of 176 patients) and 6.4% (11 of 173 patients), respectively (risk ratio, 0.36; 95% CI, 0.12-1.04; P = 0.0599). The incidence rate of cholangitis was 1.7% (3 of 176 patients) in the antibiotic prophylaxis group and 6.4% (11 of 173 patients) in the placebo group (risk ratio, 0.27; 95% CI, 0.08-0.87; P = 0.0267).

DISCUSSION

Antibiotic prophylaxis before ERCP in patients with biliary obstruction resulted in a significantly lower risk of infectious complications, especially cholangitis, than placebo ( ClinicalTrials.gov trial number NCT02958059).

Costs of purchase, maintenance, microbiological control, and reprocessing of a reusable duodenoscope

Background and study aims The costs of reusable endoscope reprocessing have been evaluated, yet external validity of the findings remains challenging. The aim of this study was to assess the costs of purchase, maintenance, microbiological control, and reprocessing of a reusable duodenoscope per endoscopic retrograde cholangiopancreatography (ERCP) in France. Study findings exclude the costs of infection, downtime due to breakdown, reprocessing single-use material disposal, and device disposal, all of which should also be considered. Materials and methods The study encompassed both observational and theoretical approaches. Observational data were collected in four hospitals, from December 2019 to December 2020, with an ad hoc survey, based on 2016 and 2018 national guidelines for duodenoscope reprocessing. Costs were modeled, using the same guidelines, assuming a mean workload of 223 ERCP/duodenoscope/year. Results The mean observed cost of purchase, maintenance, microbiological control, reprocessing (human resources and consumables), and overhead (additional 35%) with a reusable duodenoscope was €80.23 (standard deviation €3.77) per ERCP. The corresponding mean theoretical cost was €182.71 for manual reprocessing without endoscope drying cabinet (EDC), €191.36 for manual reprocessing with EDC, €235.25 for automated endoscope reprocessing (AER) without EDC, and €253.62 for AER with EDC. Conclusions Because procedures, equipment, volume activity, number of duodenoscopes, human resources, and internal work organizations are hospital-dependent, observed costs varied between hospitals. Theoretical costs were higher than observed costs, showing that the theoretical approach is not sufficient. Hypotheses to explain the difference between the two approaches include failing to measure some costs in the survey and challenges in guideline implementation.

Disposable Duodenoscopes: Evidence and Open Issues

Duodenoscope-related infections are a major concern in medicine and GI endoscopy, especially in fragile patients. Disposable duodenoscopes seem to be the right tool to minimize the problem: a good choice for patients with many comorbidities or with a high risk of carrying multidrug resistant bacteria. Urgent endoscopy could also be a good setting for the use of single-use duodenoscopes, especially when the risk of the infection cannot be evaluated. Their safety and efficacy in performing ERCP has been proven in many studies. However, randomized clinical trials and comparative large studies with reusable scopes are lacking. Moreover, the present early stage of their introduction on the market does not allow a large economical evaluation for each health system. Thus, accurate economical and safety comparisons with cap-disposable duodenoscopes are needed. Moreover, the environmental impact of single-use duodenoscopes should be carefully evaluated, considering the ongoing climate change. In conclusion, definitive guidelines are needed to choose wisely the appropriate patients for ERCP with disposable duodenoscopes as the complete switch to single-use duodenoscopes seems to be difficult, to date. Many issues are still open, and they need to be carefully evaluated in further, larger studies.

Transmission of oral microbiota to the biliary tract during endoscopic retrograde cholangiography

BACKGROUND

Endoscopic retrograde cholangiography (ERC) possesses a translocation risk of microbes to the biliary system. We studied bile contamination during ERC and its impact on patients' outcome in a real-life-situation.

METHODS

Ninety-nine ERCs were analyzed and microbial samples were taken from the throat before and from bile during ERC and from irrigation fluid of the duodenoscope before and after ERC.

RESULTS

91.2% of cholangitis patients had detectable microbes in the bile (sensitivity 91%), but the same was true for 86.2% in the non-cholangitis group. Bacteroides fragilis (p=0.015) was significantly associated with cholangitis. In 41.7% of ERCs with contaminated endoscopes these microbes were found in the bile after the procedure. Analysis of duodenoscopes' irrigation liquid after ERC matched the microbial bile analysis of these patients in 78.8%. Identical microbial species were in throat and in bile samples of the same ERC in 33% of all cases and in 45% in the non-cholangitis group. Transmission of microbes to the biliary tract did not result in more frequent cholangitis, longer hospital stays, or worse outcome.

CONCLUSIONS

During ERC bile samples are regularly contaminated with microbes of the oral cavity but it did not affect clinical outcome.

Green endoscopy: British Society of Gastroenterology (BSG), Joint Accreditation Group (JAG) and Centre for Sustainable Health (CSH) joint consensus on practical measures for environmental sustainability in endoscopy

GI endoscopy is highly resource-intensive with a significant contribution to greenhouse gas (GHG) emissions and waste generation. Sustainable endoscopy in the context of climate change is now the focus of mainstream discussions between endoscopy providers, units and professional societies. In addition to broader global challenges, there are some specific measures relevant to endoscopy units and their practices, which could significantly reduce environmental impact. Awareness of these issues and guidance on practical interventions to mitigate the carbon footprint of GI endoscopy are lacking. In this consensus, we discuss practical measures to reduce the impact of endoscopy on the environment applicable to endoscopy units and practitioners. Adoption of these measures will facilitate and promote new practices and the evolution of a more sustainable specialty.

Good Practices on Endoscope Reprocessing in Italy: Findings of a Nationwide Survey

Background: Correct reprocessing and microbiological surveillance on endoscopes are fundamental for preventing the transmission of multi-drug resistant strains and device-related infections. Methods: A questionnaire with three domains was created: (1) centre characteristics; (2) endoscope reprocessing procedures; and (3) application of microbiological surveillance. Nurses working in endoscopic units across Italy were invited to anonymously fill out the questionnaire on the SurveyMonkey platform between November 2021 and February 2022. Results: A total of 82 out of 132 endoscopic centres participated in the survey, with at least one centre from each Italian region. Data found different concerns regarding the current practice of both reprocessing and microbiological surveillance. According to respondents, the training on reprocessing was performed through theoretical training and only in 10% of centres; the microbiological surveillance was regularly performed in 59% of centres; and sampled endoscopes were not excluded for use in 31% of centres performing the surveillance until the outcome was pending, and when positive, 72% maintained them in quarantine until a successive negative result. Conclusions: Reprocessing and microbiological surveillance currently present several criticisms along the endoscopic centres in Italy. Our survey highlights the need for the correct application of the national recommendations in each endoscopic centre to prevent the potential transmission of endoscope-related infections.

A dynamic flow model mimicking duodenoscope reprocessing after bacterial contamination for translational research

OBJECTIVE

Duodenoscopy-associated infections and outbreaks are reported globally despite strict adherence to duodenoscope reprocessing protocols. Therefore, new developments in the reprocessing procedure are needed.

DESIGN

We evaluated a novel dynamic flow model for an additional cleaning step between precleaning and manual cleaning in the reprocessing procedure.

METHODS

A parallel plate flow chamber with a fluorinated ethylene propylene bottom plate was used to mimic the duodenoscope channels. The flow chamber was inoculated with a suspension containing Klebsiella pneumoniae to simulate bacterial contamination during a duodenoscopic procedure. After inoculation the flow chamber was flushed with a detergent mimicking precleaning. Subsequently the flow chamber was subjected to different interventions: flow with phosphate-buffered saline (PBS), flow with 2 commercial detergents, flow with sodium dodecyl sulfate with 3 different concentrations, and flow with microbubbles. Adhering bacteria were counted using phase-contrast microscopy throughout the experiment, and finally, bacterial viability was assessed.

RESULTS

During precleaning both PBS and 1% (v/v) Neodisher Mediclean Forte were able to desorb bacteria, but neither proved superior. After precleaning only sodium dodecyl sulfate could desorb bacteria.

CONCLUSIONS

Flushing during precleaning is an essential step for reducing adhering luminal bacteria, and sodium dodecyl sulfate is a promising detergent for bacterial desorption from duodenoscope channels after precleaning.

Risk factors for infections after endoscopic retrograde cholangiopancreatography (ERCP): a retrospective cohort analysis of US Medicare Fee-For-Service claims, 2015-2021

OBJECTIVE

Contaminated reprocessed duodenoscopes pose a serious threat to patients in the endoscopy unit. Despite manufacturer changes to reprocessing guidelines, 20% of reprocessed duodenoscopes meet criteria for quarantine-level contamination based on microbiological or ATP testing. We aimed to examine risk factors for postendoscopic retrograde cholangiopancreatography (ERCP) infection.

DESIGN

Retrospective cohort analysis.

SETTING

US Medicare Fee-For-Service claims (2015-2021) and all-payer data (2017).

PARTICIPANTS

In the Medicare data, 823 575 ERCP procedures were included. The all-payer five-state data, 16 609 procedures were included.

INTERVENTIONS

ERCP was identified by Current Procedural Terminology and International Classification of Disease (ICD) procedure codes. We identified inpatient infections using ICD diagnosis codes.

OUTCOME MEASURES

A logistic regression model predicted risk factors for infections occurring within 7-day and 30-day periods following ERCP. 7-day and 30-day all-cause hospitalisations and post-ERCP pancreatitis were also examined.

RESULTS

Post-ERCP infection occurred within 3.5% of 7-day and 7.7% of 30-day periods in Medicare. Disposable duodenoscopes were billed in 711 procedures, with 1.4% (n=10, 7-day) and 3.5% (n=25, 30-day) post-ERCP infections. Urgent ERCPs were the strongest risk factor for infections in the 7-day period (OR 3.3, 95% CI 3.2 to 3.4). Chronic conditions, sex (male), age (older) and race (non-white) were also risk factors. In the all-payer five-state data, fewer infections (2.4%, 7 days) were observed. No difference arose between Medicare and other payers for 7-day period infections (OR 1.0, 95% CI 0.7 to 1.3).

CONCLUSIONS

Urgent ERCPs, patient chronic conditions and patient demographics are post-ERCP infection risk factors. Patients with infection risk factors should be targeted for specialised infection control prevention measures, including disposable duodenoscopes.

Assessment of postmanual cleaning adenosine triphosphate tests to prevent the use of contaminated duodenoscopes and linear echoendoscopes: the DETECT study

BACKGROUND AND AIMS

We investigated whether the use of postmanual cleaning adenosine triphosphate (ATP) tests lowers the number of duodenoscopes and linear echoendoscopes (DLEs) contaminated with gut flora.

METHODS

In this single-center before-and-after study, DLEs were ATP tested after cleaning. During the control period, participants were blinded to ATP results: ATP-positive DLEs were not recleaned. During the intervention period, ATP-positive DLEs were recleaned. DLEs underwent microbiologic sampling after high-level disinfection (HLD) with participants blinded to culture results.

RESULTS

Using 15 endoscopes of 5 different DLE types, we included 909 procedures (52% duodenoscopes, 48% linear echoendoscopes). During the intervention period, the absolute rate of contamination with gut flora was higher (16% vs 21%). The main analysis showed that contamination was less likely to occur in the intervention period (odds ratio, .32; 95% credible interval [CI], .12-.85). A secondary analysis showed that this effect was based on 1 particular duodenoscope type (estimated probability, 39% [95% CI, 18%-64%] vs 9% [95% CI, 2%-21%]), whereas no effect was seen in the other 4 DLE types. In detail, of the 4 duodenoscopes of this type, 2 had lower contamination rates (69% vs 39% and 36% vs 10%). During the control period, both these duodenoscopes had multiple episodes with ongoing contamination with the same microorganism that ended weeks before the start of the intervention period (ie, they were not terminated by ATP testing).

CONCLUSIONS

Postmanual cleaning ATP tests do not reduce post-HLD gut flora contamination rates of DLEs. Hence, postcleaning ATP tests are not suited as a means for quality control of endoscope reprocessing.

Gastrointestinal endoscope contamination rates - elevators are not only to blame: a systematic review and meta-analysis

Background and study aims  Duodenoscopes that are contaminated due to inadequate reprocessing are well-documented. However, studies have demonstrated poor reprocessing of other kinds of endoscopes as well, including echoendoscopes, gastroscopes, and colonoscopes. We estimated the contamination rate beyond the elevator of gastrointestinal endoscopes based on available data. Methods  We searched PubMed and Embase from January 1, 2010 to October 10, 2020, for studies investigating contamination rates of reprocessed gastrointestinal endoscopes. A random-effects model was used to calculate the contamination rate of patient-ready gastrointestinal endoscopes. Subgroup analyses were conducted to investigate differences among endoscope types, countries, and colony-forming unit (CFU) thresholds. Results  Twenty studies fulfilled the inclusion criteria, including 1,059 positive cultures from 7,903 samples. The total contamination rate was 19.98 % ± 0.024 (95 % confidence interval [Cl]: 15.29 %-24.68 %; I ²  = 98.6 %). The contamination rates of colonoscope and gastroscope channels were 31.95 % ± 0.084 and 28.22 % ± 0.076, respectively. Duodenoscope channels showed a contamination rate of 14.41 % ± 0.029. The contamination rates among studies conducted in North America and Europe were 6.01 % ± 0.011 and 18.16% ± 0.053 %, respectively. The contamination rate among studies using a CFU threshold > 20 showed contamination of 30.36 % ± 0.094, whereas studies using a CFU threshold < 20 showed a contamination rate of 11 % ± 0.026. Conclusions  On average, 19.98 % of reprocessed gastrointestinal endoscopes may be contaminated when used in patients and varies between different geographies. These findings highlight that the elevator mechanism is not the only obstacle when reprocessing reusable endoscopes; therefore, guidelines should recommend more surveillance of the endoscope channels as well.

Single-use duodenoscopes for the prevention of endoscopic retrograde cholangiopancreatography -related cross-infection – from bench studies to clinical evidence

BACKGROUND

Several strategies have been implemented to reduce or abolish the life-threatening risk of endoscopic retrograde cholangiopancreatography (ERCP)-related multidrug-resistant infections due to duodenoscopes contaminations; among those strategies, serial microbiologic tests, thorough reprocessing schedules, and use of removable scope cap have been adopted, but the potential cross-infection risk was not eliminated.

AIM

To review available evidence in the field of single-use duodenoscopes (SUD) use for ERCP.

METHODS

An overview on ongoing clinical studies was also performed to delineate which data will become available in the next future.

RESULTS

One bench comparative study and four clinical trials performed with EXALT model-D (Boston Scientific Corp., United States) have been identified. Of them, one is a randomized controlled trial, while the other three studies are prospective single-arm, cross-over studies. Pooled technical success rate (4 studies, 368 patients) was 92.9% [95% confidence interval (CI): 89.9-95.5; I²: 11.8%]. Pooled serious adverse event (4 studies, 381 patients) rate was 5.9% [3.7%-8.5%; I²: 0.0%].

CONCLUSION

Although few clinical trials are available, evidence is concordant in identifying an absolute feasibility and safety and feasibility for SUD use for ERCP. The expertise and quality of evidence in this field are going to be improved by further large clinical trials; data on cost-effectiveness and environmental impact will be needed for a worldwide spread of SUD use for ERCP.

A cost comparison between reusable flexible and disposable laryngoscopes

OBJECTIVES

To compare the costs of disposable laryngoscopes to reusable scopes in outpatient and inpatient settings.

METHODS

The total variable and fixed costs involved in flexible scope reprocessing were collected from two general otolaryngology clinics, a pediatric otolaryngology clinic, and a children's hospital. Variable costs of disposable materials and labor were collected from 65 scope reprocessing events to identify the cost of reprocessing. Fixed costs of scope maintenance, monitors, video towers, and storage equipment were collected from financial records. Fixed and variable costs were analyzed to identify the cost per scope event. The costs were then compared to a theoretical model where disposable scopes were used to meet the volume demands of each clinic and children's hospital setting. The model of disposable scopes was generated after obtaining volume costs specific to each setting from a disposable scope company.

RESULTS

The average cost of a reusable scope model per scope event was $66.02 ± 4.49 at the three clinics and $130.66 at the children's hospital. The average cost of the disposable scope model per scope event was $152.55 ± 0.55 in the three clinics and $172.61 in the children's hospital. The cost differences were $86.53 ± 3.96 and $41.95 respectively.

CONCLUSIONS

In an outpatient clinic, reusable scopes are less expensive than a disposable scope model. In children's hospital inpatient setting, the difference in costs between disposable and reusable scopes is lower. When considering other non-economic factors, disposable scopes may be a feasible option, especially in the children's hospital setting.

Healthcare worker feedback on duodenoscope reprocessing workflow and ergonomics

BACKGROUND

The objectives of this survey study were to assess duodenoscope precleaning and manual cleaning times, identify human factors issues in duodenoscope reprocessing workflow or ergonomics, and ascertain any best practices in duodenoscope reprocessing.

METHODS

Researchers developed the confidential, qualitative, online Duodenoscope Reprocessing Workflow and Ergonomic Design Human Factors Survey with an intended audience of healthcare workers (HCWs) who routinely perform duodenoscope precleaning or manual cleaning. The unrestricted survey link was distributed to target HCW email addresses in December 2020; the survey closed in January 2021.

RESULTS

Three hundred and forty-one individuals completed the survey. Most respondents complete duodenoscope precleaning in 10 minutes or less and manual cleaning in 16-to-30 minutes. Most respondents' facilities use fixed distal endcap duodenoscopes. Most respondents experience pressure to work faster when cleaning duodenoscopes and reported that cleaning duodenoscopes caused fatigue or discomfort in at least one body part. Mentoring HCWs and retaining experienced staff were 2 primary duodenoscope reprocessing best practices identified by respondents.

DISCUSSION AND CONCLUSIONS

To enhance duodenoscope cleaning, facilities should provide ample reprocessing work spaces with incorporated height-adjustable work surfaces, train HCWs on validated duodenoscope reprocessing instructions, provide step-by-step instructions for HCWs when duodenoscope cleaning is performed, mentor reprocessing HCWs, and retain experienced staff.

Duodenoscope-Acquired Infections: Risk Factors to Consider

In the wake of highly publicized duodenoscope-associated outbreaks caused by multidrug-resistant organisms (MDRO), a herculean effort was made to understand the conditions that led to these transmission events. Although there is now a clearer picture on how these outbreaks happened, there are still significant data gaps when it comes to understanding the rate of duodenoscope-acquired infections (DAIs), especially in nonoutbreak situations. Recent publications indicate that DAIs are still occurring and suggest that infection rates are higher than currently believed. Given this data gap, it is important to identify those patient populations that are most at risk of postprocedure infection, so that appropriate infection control measures may be implemented. Although those patients receiving antibiotic prophylaxis are most at risk for infection, there are additional risk factors that should be considered. For the purposes of this review, risk factors for infection were divided into three broad categories as follows: (1) those that increase patient susceptibility to infection, (2) those related to the endoscopic procedure, and (3) those factors that put reusable duodenoscope inventories at risk of contamination. Infection risk is a complex interaction between the immune status of the patient, the characteristics of the infectious agent (antibiotic sensitivity, virulence factors, and epidemiology), and the environment of care. Because of this complexity, any assessment of the risk of infection should be performed on a case-by-case basis. There is a dearth of information on infection risk for those patients undergoing endoscopic retrograde cholangiopancreatograpy (ERCP), especially in the context of the development and implementation of new device technology, and new endoscopic procedures that are increasing in complexity. This narrative review was developed using the Medical Subject Heading (MeSH) terms to perform an electronic search in PubMed with the goal of generating a summary of the patient, procedural, and duodenoscope-associated factors that increase the risk of infection in patients undergoing ERCP. This review provides practical information regarding the segmentation of ERCP patients by infection risk, so that endoscopists can make informed decisions about the risk benefits of using enhanced duodenoscope technologies in the care of their patients.

A narrative review on current duodenoscope reprocessing techniques and novel developments

Duodenoscopy-associated infections occur worldwide despite strict adherence to reprocessing standards. The exact scope of the problem remains unknown because a standardized sampling protocol and uniform sampling techniques are lacking. The currently available multi-society protocol for microbial culturing by the Centers for Disease Control and Prevention, the United States Food and Drug Administration (FDA) and the American Society for Microbiology, published in 2018 is too laborious for broad clinical implementation. A more practical sampling protocol would result in increased accessibility and widespread implementation. This will aid to reduce the prevalence of duodenoscope contamination. To reduce the risk of duodenoscopy-associated pathogen transmission the FDA advised four supplemental reprocessing measures. These measures include double high-level disinfection, microbiological culturing and quarantine, ethylene oxide gas sterilization and liquid chemical sterilization. When the supplemental measures were advised in 2015 data evaluating their efficacy were sparse. Over the past five years data regarding the supplemental measures have become available that place the efficacy of the supplemental measures into context. As expected the advised supplemental measures have resulted in increased costs and reprocessing time. Unfortunately, it has also become clear that the efficacy of the supplemental measures falls short and that duodenoscope contamination remains a problem. There is a lot of research into new reprocessing methods and technical applications trying to solve the problem of duodenoscope contamination. Several promising developments such as single-use duodenoscopes, electrolyzed acidic water, and vaporized hydrogen peroxide plasma are already applied in a clinical setting.

Device profile of the EXALT Model D single-use duodenoscope for endoscopic retrograde cholangiopancreatography: overview of its safety and efficacy

Introduction: The management of pancreaticobiliary disorders relies heavily on endoscopic retrograde cholangiopancreatography, which is performed with a duodenoscope. Bacterial colonization of reusable duodenoscopes leading to subsequent infectious outbreaks is well recognized and remains an issue despite efforts to optimize best practices in high-level disinfection. The EXALT Model D duodenoscope (EXALT) (Boston Scientific Corporation, Marlborough, MA) is a single-use device, designed to achieve technical equivalency with reusable devices while eliminating the potential for device-related outbreaks.Areas covered: This review covers the challenges associated with reprocessing duodenoscopes and the development of duodenoscope-related infections, with an emphasis on the use of single-use duodenoscopes as a potential solution to this issue.Expert Opinion: Duodenoscope-related infections are an increasingly recognized problem. Infectious outbreaks harm patients, significantly affect providers and medical centers, and can erode patient trust in the health-care system. Single-use duodenoscopes eliminate both the risk of device-related infection transmission and the need for burdensome duodenoscope reprocessing. In clinical evaluations, the EXALT device has demonstrated an equivalent technical performance and provider satisfaction compared to reusable duodenoscopes. Increasing use of this device will clarify how it compares to reusable duodenoscopes in a variety of clinical settings among endoscopists of varying skills levels.

Single-use duodenoscopes and duodenoscopes with disposable end caps

BACKGROUND AND AIMS

Multidrug-resistant infectious outbreaks associated with duodenoscopes have been documented internationally. Single-use duodenoscopes, disposable distal ends, or distal end cap sealants could eliminate or reduce exogenous patient-to-patient infection associated with ERCP.

METHODS

This document reviews technologies that have been developed to help reduce or eliminate exogenous infections because of duodenoscopes.

RESULTS

Four duodenoscopes with disposable end caps, 1 end sheath, and 2 disposable duodenoscopes are reviewed in this document. The evidence regarding their efficacy in procedural success rates, reduction of duodenoscope bacterial contamination, clinical outcomes associated with these devices, safety, and the financial considerations are discussed.

CONCLUSIONS

Several technologies discussed in this document are anticipated to eliminate or reduce exogenous infections during endoscopy requiring a duodenoscope. Although disposable duodenoscopes can eliminate exogenous ERCP-related risk of infection, data regarding effectiveness are needed outside of expert centers. Additionally, with more widespread adoption of these new technologies, more data regarding functionality, medical economics, and environmental impact will accrue. Disposable distal end caps facilitate duodenoscope reprocessing; postmarketing surveillance culture studies and real-life patient infection analyses are important areas of future research.

Use of a novel single-use disposable duodenoscope for ERCP: selected clips from a real-world case series

Background and Aims

Single-use/disposable duodenoscopes represent one strategy to decrease the risk of patient infection related to ERCP. A preliminary case series was performed to demonstrate the feasibility and performance of a new single-use duodenoscope in a real-world clinical setting.

Methods

A single expert endoscopist performed ERCP for standard indications using a single-use duodenoscope.

Results

Videos of several key steps of ERCP obtained from 4 patients are shown to demonstrate that these steps can successfully be performed using the new single-use device. Clip 1 shows a patient with a large pancreatic duct stone in whom the image quality and maneuverability are demonstrated. Clip 2 shows a patient with choledocholithiasis and demonstrates bile duct cannulation, cholangiography, and sphincterotomy. Clip 3 shows a patient with acute cholecystitis and choledocholithiasis who underwent bile duct cannulation, sphincterotomy, and balloon sweeps. Clip 4 shows a patient with a history of liver transplant and refractory biliary anastomotic stricture who presented with abnormal liver tests and fever and underwent removal of a metal stent and placement of plastic stents.

Conclusions

A single-use duodenoscope can successfully accomplish fundamental steps of ERCP. This device can potentially eliminate the risk of patient-to-patient infections linked to contaminated instruments. Larger studies are required to assess device performance.

Methods for Endoscope Reprocessing

Over the past 2 decades, in hospital centers worldwide, there have been numerous outbreaks of multidrug-resistant organisms that have since been attributed to endoscopic transmission of the infections between patients, primarily from duodenoscopes. These outbreaks have focused the attention of endoscope manufacturers, professional societies, and regulatory agencies on improving the reprocessing of these devices. The key steps in this process are point-of-use precleaning, leak testing, manual cleaning, high-level disinfection, and finally drying and storage. The promise of these initial efforts suggest that the aim of minimizing and ultimately eliminating events of endoscope-/duodenoscope-associated transmission of infectious organisms between patients can be achieved.

Remote video auditing in the endoscopy unit for evaluation of duodenoscope reprocessing in a tertiary care center

BACKGROUND : A significant proportion of duodenoscope-transmitted infections have resulted from errors related to reprocessing. Remote video auditing (RVA) is a tool that can monitor reprocessing compliance but it has not been previously evaluated in a tertiary care setting. The aims of this study were to evaluate: 1) RVA feasibility in a tertiary care setting (defined as the ability to audit every step of duodenoscope reprocessing without delaying the next procedure due to unavailability of duodenoscopes); and 2) the use of RVA as a compliance monitoring tool. METHODS : This was a prospective study at a tertiary care center. A video camera with offsite monitoring was installed in March 2018. Auditors delivered a compliance score after each procedure. The duodenoscope was not used until it passed the audit. Feasibility and compliance data were collected from April 2018 to August 2019 after a 1-month run-in phase. Both per-step compliance and overall 100 % compliance rates were measured. RESULTS : Of 743 duodenoscope reprocessing procedures, 32 666 individual steps were audited and 99.9 % of the steps were fully viewable. The mean time per audit was 38.3 minutes, the mean duodenoscope turnover time was 76.1 minutes, and there were no delays to the next procedure due to unavailability of duodenoscopes. The per-step compliance rate was 99.5 % but the overall 100 % compliance rate was 90.3 %. CONCLUSIONS : The use of RVA in duodenoscope reprocessing was feasible and promoted sustained high-level compliance in a tertiary care center.

Nationwide risk analysis of duodenoscope and linear echoendoscope contamination

BACKGROUND AND AIMS

Contaminated duodenoscopes and linear echoendoscopes (DLEs) pose a risk for infectious outbreaks. To identify DLEs and reprocessing risk factors, we combined the data from the previously published nationwide cross-sectional PROCESS 1 study (Prevalence of contamination of complex endoscopes in the Netherlands) with the follow-up PROCESS 2 study.

METHODS

We invited all 74 Dutch DLE centers to sample ≥2 duodenoscopes during PROCESS 1, and all duodenoscopes as well as linear echoendoscopes during PROCESS 2. The studies took place 1 year after another. Local staff sampled each DLE at ≤6 sites according to uniform methods explained by online videos. We used 2 contamination definitions: (1) any microorganism with ≥20 colony-forming units (CFU)/20 mL (AM20) and (2) presence of microorganisms with GI or oral origin, independent of CFU count (MGOs). We assessed the factors of age and usage by performing an analysis of pooled data of both PROCESS studies; additional factors including reprocessing characteristics were only recorded in PROCESS 2.

RESULTS

Ninety-seven percent of all Dutch centers (72 of 74; PROCESS 1, 66; PROCESS 2, 61) participated in one of the studies, sampling 309 duodenoscopes and 64 linear echoendoscopes. In total, 54 (17%) duodenoscopes and 8 (13%) linear echoendoscopes were contaminated according to the AM20 definition. MGOs were detected on 47 (15%) duodenoscopes and 9 (14%) linear echoendoscopes. Contamination was not age or usage dependent (all P values ≥.27) and was not shown to differ between the reprocessing characteristics (all P values ≥.01).

CONCLUSIONS

In these nationwide studies, we found that DLE contamination was independent of age and usage. These results suggest that old and heavily used DLEs, if maintained correctly, have a similar risk for contamination as new DLEs. The prevalence of MGO contamination of ∼15% was similarly high for duodenoscopes as for linear echoendoscopes, rendering patients undergoing ERCP and EUS at risk for transmission of microorganisms.

Rate and impact of duodenoscope contamination: A systematic review and meta-analysis

BACKGROUND

Multiple infection outbreaks have been linked to contaminated duodenoscopes worldwide. However, the contamination rate of patient-ready duodenoscopes varies highly amongst published studies testing this subject. We aimed to estimate the contamination rate of reprocessed patient-ready duodenoscopes for endoscopic retrograde cholangio-pancreatography (ERCP) based on currently available data.

METHODS

We searched the PubMed and Embase databases from January 1, 2010 until March 10, 2020, for citations investigating contamination rates of reprocessed patient-ready duodenoscopes. Studies not assessing other types of endoscopes than duodenoscopes were excluded from the analysis. Study eligibility and data extraction was evaluated by three reviewers independently. A random-effects model (REM) based on the proportion distribution was used to calculate the pooled total contamination rate of reprocessed patient-ready duodenoscopes. Subgroup analyses were carried out to assess contamination rates when using different reprocessing methods by comparing single high-level disinfection (HLD) with double HLD and ethylene oxide (EtO) gas sterilization. Additionally, we investigated the contamination rate between studies conducted following an outbreak compared to non-outbreak-initiated studies.

FINDINGS

We identified 15 studies that fulfilled the inclusion, which included 925 contaminated duodenoscopes from 13,112 samples. The calculated total weighted contamination rate was 15.25% ± 0.018 (95% confidence interval [Cl]: 11.74% - 18.75%). The contamination rate after only using HLD was 16.14% ± 0.019 (95% Cl: 12.43% - 19.85%) and after using either dHLD or EtO the contamination rate decreased to 9.20% ± 0.025 (95% Cl: 4.30% - 14.10%). Studies conducted following an outbreak (n=4) showed a 5.72% ± 0.034 (95% Cl: 0.00% - 12.43%) contamination rate, and non-outbreak-initiated studies (n=11) revealed a contamination rate of 21.50% ± 0.031 (95% Cl: 15.35% - 27.64%).

INTERPRETATION

This is the first meta-analysis to estimate the contamination rate of patient-ready duodenoscopes used for ERCP. Based on the available literature, our analysis demonstrates that there is a 15.25% contamination rate of reprocessed patient-ready duodenoscopes. Additionally, the analysis indicates that dHLD and EtO reprocessing methods are superior to single HLD but still not efficient in regards to cleaning the duodenoscopes properly. Furthermore, studies conducted following an outbreak did not entail a higher contamination rate compared to non-outbreak-initiated studies.

FUNDING

The authors received no financial support for the research, authorship, and/or publication of this article.

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.

Duodenoscope-associated infections: a review

Flexible digestive endoscopes are used for the management of various conditions with hundreds of thousands of therapeutic procedures performed worldwide each year. Duodenoscopes are indispensable tools for the delivery of minimally invasive vital care of numerous pancreaticobiliary disorders. Despite the fact that nosocomial infections after endoscopic retrograde cholangiopancreatography (ERCP) have always been among the most frequently cited postprocedural complications, recent emergence of duodenoscope-transmitted multiple drug-resistant bacterial infections has led to intense research and debate yet with no clearly delineated solution. Duodenoscope-transmitted nosocomial infections have become one of the most visible topics in the recent literature. Hundreds of high-impact articles have therefore been published in the last decade. This review article discusses how such infections were seen in the past and what is the current situation in both research and practice and thus tries to solve some of the unanswered questions for the future. With the persistence of nosocomial infections despite strict adherence to both manufacturer-issued reprocessing protocols and international guidelines and regulations, an urgent and proper microbiologically driven common action is needed for controlling such nosocomial worldwide threat.

Independent root-cause analysis of contributing factors, including dismantling of 2 duodenoscopes, to investigate an outbreak of multidrug-resistant Klebsiella pneumoniae

BACKGROUND AND AIMS

Worldwide, an increasing number of duodenoscope-associated outbreaks are reported. The high prevalence rate of contaminated duodenoscopes puts patients undergoing ERCP at risk of exogenous transmission of microorganisms. The contributing factors of the duodenoscope design to contamination are not well understood. This article reports on the investigation after the outbreak of a multidrug-resistant Klebsiella pneumoniae (MRKP) related to 2 Olympus TJF-Q180V duodenoscopes.

METHODS

We conducted a contact patient screening and microbiologic laboratory database search. Reprocessing procedures were audited, and both duodenoscopes were fully dismantled to evaluate all potential contamination factors. Outcomes were reviewed by an experienced independent expert.

RESULTS

In total, 102 patients who had undergone an ERCP procedure from January to August 2015 were invited for screening. Cultures were available of 81 patients, yielding 27 MRKP-infected or -colonized patients. Ten patients developed an MRKP-related active infection. The 2 duodenoscopes had attack rates (the number of infected or colonized cases/number of exposed persons) of 35% (17/49) and 29% (7/24), respectively. Identical MRKP isolates were cultured from channel flushes of both duodenoscopes. The review revealed 4 major abnormalities: miscommunication about reprocessing, undetected damaged parts, inadequate repair of duodenoscope damage, and duodenoscope design abnormalities, including the forceps elevator, elevator lever, and instrumentation port sealing.

CONCLUSIONS

Outbreaks are associated with a combination of factors, including duodenoscope design issues, repair issues, improper cleaning, and systemic monitoring of contamination. To eliminate future duodenoscope-associated infections, a multipronged approach is required, including clear communication by all parties involved, a reliable servicing market, stringent surveillance measures, and eventually new duodenoscope designs and reprocessing procedures with a larger margin of safety.

Use of ethylene-oxide gas sterilisation to terminate multidrug-resistant bacterial outbreaks linked to duodenoscopes

Background

Cleaning and high-level disinfection have been the standard in the USA and other countries for reprocessing flexible endoscopes, including duodenoscopes and other types of gastrointestinal endoscopes. For decades, this practice has been a cornerstone for infection prevention in the endoscopic setting. However, amid recent reports associating the use of duodenoscopes with infections and outbreaks of carbapenem-resistant Enterobacteriaceae (CRE) and related multidrug-resistant organisms (MDROs), reasonable questions about the adequacy of current practices for reprocessing duodenoscopes have emerged.

Objectives

To review and evaluate the adequacy of current reprocessing practices for preventing duodenoscopes from transmitting CRE and related MDROs.

Methods

The MEDLINE/PubMed database was searched to identify published cases associating confirmed (or suspected) infections of CRE or a related MDRO with exposure to a duodenoscope since 2012, when duodenoscopes became a recognised risk factor for the transmission of CRE. The Internet was also searched to identify news articles and other reports documenting eligible cases occurring during this same timeframe but not identified during the MEDLINE database’s search. The Food and Drug Administration’s (FDA) medical device database was queried to identify regulatory reports describing these same types of cases, also recorded since 2012. The clinical and reprocessing details of each eligible case were reviewed to identify (when possible): (a) the reprocessing method (eg, high-level disinfection) performed at the time of the infections, (b) whether the facility’s compliance with the manufacturer’s reprocessing instructions was confirmed, and (c) the measure(s) or corrective action(s) the facility implemented to prevent additional multidrug-resistant infections.

Results

Seventeen cases in the USA and six in other countries (primarily Europe) associating infections (and colonizations) of CRE or a related MDRO with exposure to a duodenoscope were reviewed. Fourteen of these 23 outbreaks were caused by CRE, and six by a related MDRO. Two of these six latter cases identified Klebsiella pneumoniae carrying the mcr-1 gene as the pathogen. For 12 of these 23 cases, it was reported or implied that the duodenoscope was being high-level disinfected at the time of the infections, consistent with published guidelines. For the remaining 11 cases, the associated report(s) did not clearly identify how the duodenoscope was being reprocessed at the time of the infections (although it may be reasonably concluded that at least some, if not all, of these 11 cases involved high-level disinfection).

Further, eight of the 23 cases reported the duodenoscope was being reprocessed in accordance with the manufacturer’s instructions for use (and professional guidelines) at the time of the infections. Seven of the cases discussed the design of the duodenoscope (eg, the forceps elevator mechanism) in the context of reprocessing and the infections. Three of the cases identified one or more reprocessing lapses, including inadequate cleaning, delayed reprocessing and improper drying and/or storage of the duodenoscope. Most of these 23 cases were associated with exposure to a duodenoscope model featuring a sealed elevator-wire channel. Six of the cases reported adopting (or in one case supplementing high-level disinfection with) ethylene oxide (EO) gas sterilisation of the duodenoscope, with at least three reporting this measure terminated the outbreak. Other measures adopted to prevent additional infections included removing the implicated duodenoscope from use, re-training staff about proper cleaning, microbiological culturing of the duodenoscope and returning the duodenoscope to the manufacturer for evaluation, maintenance and/or repair.

Conclusions

This study's findings suggest current reprocessing practices may not always be sufficiently effective to prevent a duodenoscope from transmitting CRE and related MDROs, at least in some circumstances including an outbreak setting. Factors this review identified that may contribute to the device remaining contaminated after reprocessing include the device’s design; breaches of recommended reprocessing guidelines (eg, inadequate manual cleaning, delayed reprocessing or improper device storage); damage to the device; lacking servicing, maintenance or repair; and/or the presence of biofilms. Measures that can mitigate the impact of these and other reprocessing challenges and reduce, if not eliminate, the risk of transmission of CRE or a related MDRO by a duodenoscope include the use of EO gas sterilization (or another comparably effective process or method). In 2015, the FDA suggested healthcare facilities consider performing at least one of four supplemental measures, which include EO gas sterilisation, to improve the effectiveness of duodenoscope reprocessing. Whether the FDA and Centers for Disease Control and Prevention might reclassify duodenoscopes as critical devices requiring sterilisation is currently unresolved.

What's new in reprocessing endoscopes: Are we going to ensure "the needs of the patient come first" by shifting from disinfection to sterilization?

Millions of gastrointestinal endoscopes are performed each year in the United States. Gastrointestinal endoscopes become highly contaminated during use (ie, internal channels contain 7-10-log₁₀ enteric microorganisms). Currently, endoscopes (eg, bronchoscopes and gastrointestinal endoscopes) are classified as semicritical items because they contact intact mucous membranes and most commonly undergo cleaning followed by high-level disinfection, which may result in as little as a 6-log₁₀ reduction of microorganisms. Therefore, and not surprisingly, in recent years there have been multiple reports that have documented that endoscopes, especially duodenoscopes, frequently remain contaminated with bacterial pathogens after proper cleaning and disinfection. Multiple outbreaks of multidrug-resistant organisms from contaminated duodenoscopes have resulted in substantial death and morbidity. Because duodenoscopes commonly contact nonintact mucous membranes and sterile tissue, such endoscopes should be considered critical items. We propose that to ensure patient safety, we follow the Spaulding scheme and move from high-level disinfection to sterilization of reusable endoscopes or use an alternative diagnostic/therapeutic method (eg, disposable sterile endoscopes).