Comparison of automated and manual drying in the elimination of residual endoscope working channel fluid after reprocessing (with video)

A New Drying Method of Thermolabile Flexible Endoscope Channels by Laminar and Turbulent Airflow: A Prospective, Randomized-Controlled, Single-Center, Proof-of-Concept Trial

INTRODUCTION

International guidelines suggest different possibilities for drying of endoscopes during reprocessing. Clinical results of these available drying methods are not satisfactory. The aim of this study was to compare the drying cycle of a standard endoscope washer-disinfector (EWD) (standard drying method [SD]) with a shortened mandatory drying by the EWD followed by a special drying device using laminar and turbulent air flow (novel drying method [ND]).

METHODS

Sixty endoscopes (duodenoscopes, colonoscocopes, and gastroscopes) from 3 different manufacturers underwent high-level disinfection and drying depending on the randomization group. Operational time of drying was measured for both groups. Residual fluid in the channels was measured using a laboratory scale. After a 14-day storage period, a sample of the endoscope channels was obtained to determine bacterial contamination.

RESULTS

ND had significantly fewer residual water in endoscope channels (SD: 90% vs ND: 0%; P < 0.001) after high-level disinfection and drying and less bacterial contamination after storage for 14 days (SD: 47% vs ND: 20%; P = 0.028). Time consumed for drying in ND was also significantly shorter (SD: 16 minutes 4 seconds vs ND: 5 minutes 59 seconds; P < 0.001).

DISCUSSION

Drying with a special automatic drying device was superior compared with an EWD's drying program as evidenced by no measurable residual water, reduced microbiological contamination, and a more than 2-fold decrease in operational time. Thus, drying by laminar and turbulent airflow may represent an attractive alternative to the currently used standard approach in the reprocessing process of flexible endoscopes.

Multisociety guidance for sterilization and high-level disinfection

SHEA, in partnership with ASGE, APIC, AAMI, AORN, HSPA, IDSA, SGNA, and The Joint Commission, developed this multisociety infection prevention guidance document for individuals and organizations that engage in sterilization or high-level disinfection (HLD). This document follows the CDC Guideline for Disinfection and Sterilization in Healthcare Facilities. This guidance is based on a synthesis of published scientific evidence, theoretical rationale, current practices, practical considerations, writing group consensus, and consideration of potential harm when applicable. The supplementary material includes a summary of recommendations. The guidance provides an overview of the Spaulding Classification and considerations around manufacturers' instructions for use (MIFUs). Its recommendations address: point-of-use treatment prior to sterilization or HLD, preparation of reusable medical devices at the location of processing, sterilization, and immediate use steam sterilization (IUSS), HLD of lumened and non-lumened devices, processing of reusable medical devices used with lubricating or defoaming agents, monitoring for effectiveness of processing, handling of devices after HLD, augments and alternatives to HLD, processing of investigational devices, tracking of reusable medical devices, and approaches to implementation.

Impact of Different Pressures on the Drying Time of Flexible Endoscopes

BACKGROUND

The complex structure of endoscopes causes nonuniform drying conditions. However, current clinical drying practices lack precise guidance, leading to the insufficient drying of some endoscopes, which increases the risk of infection. The pressure of compressed air has been proven to affect the effectiveness of endoscope drying; however, specific requirements are absent. This study explored the time required for the sufficient drying of different endoscopes under various pressure conditions.

METHODS

Six different types of commonly used Olympus flexible endoscopes were selected, and for each type, multiple drying time groups were set under pressures of 0.102 and 0.204 MPa, with 10 endoscopes observed in each group.

RESULTS

Drying times varied according to the type and pressure. At 0.102 MPa, the instrument channel drying ranged from 80 s to 160 s (avg. 123 s), while suction channel ranged from 260 s to 540 s (avg. 428 s). At 0.204 MPa, the instrument channel dried in 50 s to 90 s (avg. 72 s), and suction channel in 130 s to 230 s (avg. 186 s).

CONCLUSIONS

Optimal drying times for endoscopes differ according to the type and pressure. A higher pressure (0.204 MPa) efficiently removes moisture and speeds up drying. Longer endoscopes with the same biopsy channel diameter require longer drying time. In addition, the instrument channel dries faster than the suction channel.

Efficacy of spray flushing in the reprocessing of flexible endoscopes: A randomized controlled trial

BACKGROUND

Commonly used cleaning brushes in the reprocessing of flexible endoscopes often cause damage within the working channels.

AIM

To develop a spray flushing system to achieving effective cleaning of the working channels while minimizing damage.

METHODS

This prospective study included 60 used endoscopes and 60 Teflon tubes randomly divided into a control group (n = 30) and an experimental group (n = 30). The material of Teflon tubes was the same as that of the endoscope working channel. Endoscopes in the control group were manually cleaned using traditional cleaning brushes, while those in the experimental group were cleaned using the newly developed spray flushing system. ATP levels, cleanliness, and microbiological testing of the working channels were measured. Additionally, Teflon tubes in the control group underwent 500 passes with a cleaning brush, while those in the experimental group were subjected to the spray flushing system, and channel damage was evaluated.

RESULTS

The ATP levels (RLU) in the two groups were 32.5 (13-66) and 26 (16-40), respectively (P > 0.05). Cleanliness scores were 1.5 (1-2) and 1 (1-2), respectively (P > 0.05). Debris was found in 73.3% of the control group, which was significantly higher than 46.7% in the experimental group (P < 0.05). Microbiological tests for both groups yielded negative results. Teflon tube damage in the control group was rated at 4 (4-5.25), which was significantly higher than in the experimental group 4 (3-4) (P < 0.01).

CONCLUSION

The spray flushing system demonstrated superior efficacy in removing debris and resulted in less damage to the endoscope working channels compared with traditional cleaning brushes.

Endoscope channel drying, storage, and conditions after reprocessing: How safe are they in clinical practice?

INTRODUCTION AND AIMS

Adequate drying and proper storage of flexible endoscopes are essential for maintaining quality in their reprocessing. The aim of the present study was to evaluate the drying stages, storage, and channel conditions of endoscopes through borescope inspection.

MATERIAL AND METHODS

The personnel responsible for endoscope reprocessing were interviewed. Storage conditions at 10 endoscopy facilities were inspected and an internal examination of the channels and ports of the stored equipment was carried out, utilizing a borescope. A total of 74 stored endoscope channels were evaluated.

RESULTS

Only 10% of the facilities inspected utilized transport cases for storage and only 10% had rooms exclusively used for storage. Sixty percent of the facilities did not perform any shelf-life control. All the channels evaluated were scratched and fluids were present on 69% of them.

CONCLUSIONS

Endoscope reprocessing can be improved through the implementation of drying and storage control and validation tools, as well as the use of borescopes and periodic clinical audits.

Fluid retention in endoscopes: A real-world study on drying effectiveness

BACKGROUND

Outbreaks linked to inadequate endoscope drying have infected numerous patients, and current standards and guidelines recommend at least 10 minutes of forced air for drying channels. This study evaluated a new forced-air drying system (FADS) for endoscopes.

METHODS

Drying was assessed using droplet detection cards; visual inspection of air/water connectors, suction connectors, and distal ends; and borescope examinations of endoscope interiors. Assessments were performed after automated endoscope reprocessor (AER) alcohol flush and air purge cycles and after 10-minute FADS cycles.

RESULTS

Researchers evaluated drying during encounters with 22 gastroscopes and 20 colonoscopes. After default AER alcohol and air purge cycles, 100% (42/42) of endoscopes were still wet. Substantial fluid emerged from distal ends during the first 15 seconds of the FADS cycle, and droplets also emerged from air/water and suction connectors. Following FADS cycle completion, 100% (42/42) were dry, with no retained fluid detected by any of the assessment methods.

CONCLUSIONS

Multiple endoscope ports and channels remained wet after AER cycles intended to aid in drying but were dry after the FADS cycle. This study reinforced the need to evaluate the effectiveness of current drying practices and illustrated the use of practical tools in a real-world setting.

What Are the Ready-to-Use Endoscope Channels Hiding?: Unraveling the Risks of Safe Reuse

Contamination due to failures or omissions in the reprocessing steps of gastrointestinal endoscopes is common in clinical practice. Ensuring the proper execution of each step is a challenge for reprocessing personnel. This cross-sectional study was conducted in an endoscopy setting between March and May 2021. We performed interviews about reprocessing practices, analyzed the life history of the equipment, and performed inspections through a borescope video of gastrointestinal endoscope channels that were stored and ready for use. A borescope is a complementary tool used to validate endoscope reprocessing, evaluate the internal visualization of channels, and identify changes that can compromise the safety of its use, which are often not detected in the leak test. Thirteen biopsy channels from stored gastrointestinal endoscopes were inspected. We found that 85% had stains and grooves, 69% contained moisture, and 46% had debris. There was at least one noncompliance issue in all of the channels inspected.

How effective are the alcohol flush and drying cycles of automated endoscope reprocessors? Stripped endoscope model

BACKGROUND

Effective drying of the internal channels of endoscopes is essential to prevent the growth of water-borne pathogens and to assure adequate sterilization with vaporized hydrogen peroxide or ethylene oxide. The aim of this study was to evaluate the dryness of endoscopes after a routine disinfection process in an automated endoscope reprocessor.

METHODS

Stripped endoscopes (SE) that allow for visual inspection of the inside channels were reprocessed per protocol in a large urban medical center, with a 3-minute or 10-minute air flush following reprocessing. SE was hung and observed for any water within the channels after reprocessing and after a week of ambient storage. Ready-for-use endoscopes were also randomly spot-checked for moisture visually and with moisture detection paper.

RESULTS

All SE were grossly wet after HLD with a 3-minute air flush, despite alcohol flush and drying cycle. The 10-minute air flush was effective at drying the biopsy/suction channel, but not the air/water channels. Hanging had limited effect, being most effective in the biopsy/suction channels. Of the 77 ready-for-use respiratory and gastrointestinal endoscopes assessed, 37 (48.1%) showed evidence of retained moisture.

CONCLUSIONS

Air flush cycles commonly used in the final steps of automated endoscope reprocessing may not adequately dry endoscope channels, particularly the narrower diameter air/water channels. An extended 10-minute air flush appears effective at drying the larger biopsy/suction channel, but has limited effect on the air/water channels.

Contaminated flexible endoscopes: Review of impact of channel sampling methods on culture results and recommendations for root-cause analysis

Recently, infection transmission risk associated with contaminated, patient-ready flexible endoscopes has attracted attention. Outbreaks of multidrug-resistant organisms resulting in infection and/or colonization have been particularly concerning. Recent CDC and FDA recommendations focus on reducing "exogenous" infection transmission and specifically recommend that endoscopy sites have quality systems in place for endoscope reprocessing. Another key recommendation is the culture of patient-ready endoscopes to detect contamination with organisms of concern. Remaining gaps in the guidelines include ensuring that optimal endoscope-channel sample methods are used and ensuring effective root-cause analysis and remediation when contamination is detected. In this review, we summarize the critical aspects of endoscope sample collection and present a practical approach to root-cause analysis and remedial action plans.

Initial application of deep learning to borescope detection of endoscope working channel damage and residue

Background and study aims  Outbreaks of endoscopy-related infections have prompted evaluation for potential contributing factors. We and others have demonstrated the utility of borescope inspection of endoscope working channels to identify occult damage that may impact the adequacy of endoscope reprocessing. The time investment and training necessary for borescope inspection have been cited as barriers preventing implementation. We investigated the utility of artificial intelligence (AI) for streamlining and enhancing the value of borescope inspection of endoscope working channels. Methods  We applied a deep learning AI approach to borescope inspection videos of the working channels of 20 endoscopes in use at our academic institution. We evaluated the sensitivity, accuracy, and reliability of this software for detection of endoscope working channel findings. Results  Overall sensitivity for AI-based detection of borescope inspection findings identified by gold standard endoscopist inspection was 91.4 %. Labels were accurate for 67 % of these working channel findings and accuracy varied by endoscope segment. Read-to-read variability was noted to be minimal, with test-retest correlation value of 0.986. Endoscope type did not predict accuracy of the AI system ( P  = 0.26). Conclusions  Harnessing the power of AI for detection of endoscope working channel damage and residue could enable sterile processing department technicians to feasibly assess endoscopes for working channel damage and perform endoscope reprocessing surveillance. Endoscopes that accumulate an unacceptable level of damage may be flagged for further manual evaluation and consideration for manufacturer evaluation/repair.

Storage of gastrointestinal endoscopes: when is the safe time for re-use?

ABSTRACT Objectives: to identify the safe storage time for the use of flexible gastrointestinal endoscopes after high-level disinfection, as well as the defining criteria for this time. Methods: an integrative literature review was carried out in the Virtual Health Library, PubMed, Scopus, and Web of Science, considering original articles published since 2000. Results: eleven articles were selected, whose storage times ranged from 1 to 56 days, with a predominance of one to seven days (73%). Several criteria were used to define this time, predominantly the premise of efficient processing (100%), use of alcohol flush (64%), use of drying cabinets (18%), among others. Conclusions: the criteria for determining the storage time did not show a consensus for clinical practice. Expanding the discussion of this theme with the definition of the minimum necessary conditions is of fundamental importance for the reduction of risks and safety of the procedure and the patient.

Two novel protocols for cleaning residual simethicone and fluid in patient-ready duodenoscopes

BACKGROUND AND AIM

Approximately 42-95% of working channels have been reported to show the presence of residual fluid despite endoscope reprocessing. The aim of this study was to design two novel protocols for cleaning residual simethicone and demonstrate its efficiency by evaluating the residual fluid and cleanliness in the working channels of patient-ready duodenoscopes.

METHODS

The designed protocol for cleaning residual simethicone was implemented in manual cleaning and/or high-level disinfection (HLD). The residual fluid inside the working channels was estimated by visual inspection. Adenosine triphosphate (ATP) values were evaluated to determine cleanliness after manual cleaning.

RESULTS

Manual cleaning with novel simethicone cleaning protocol demonstrated a significant decrease in fluid droplets (14.6 ± 29.9 vs 0 ± 0, P < 0.001) and ATP values (157 ± 196 relative light units [RLUs] vs 52 ± 41 RLUs, P = 0.031). HLD with simethicone cleaning protocol, using either enzymatic detergent with effective for cleaning simethicone or cleaning time set in the automatic endoscope reprocessor program for 8 min, demonstrated significant decrease in the number of fluid droplets. Follow-up after the implementation of the simethicone cleaning protocol showed a significant decrease in fluid droplets (37.4 ± 41.0 vs 2.1 ± 5.5, P = 0.003) and ATP values (271 ± 268 RLUs vs 82 ± 136 RLUs, P = 0.021).

CONCLUSIONS

Simethicone cleaning protocol is advantageous for significantly decreasing fluid droplets and ATP values within endoscope working channels. After manual cleaning with the simethicone cleaning protocol, in particular, no retained fluid droplet was observed in patient-ready duodenoscopes.

Education, training, and knowledge of infection control among endoscopy technicians and nurses

Our survey of 88 endoscopy technicians and nurses to determine their experience, training, and knowledge of infection control found that few personnel (<15%) received formal training in endoscope reprocessing or infection prevention before or after joining an endoscopy unit. While self-reported confidence in endoscope reprocessing was high (9 out of 10), knowledge of best practices in this regard lagged (average assessment score of 62%).

Efficacy of flexible endoscope drying using novel endoscope test articles that allow direct visualization of the internal channel systems

BACKGROUND

Thorough drying of flexible endoscope channels has been identified as an essential reprocessing step. Yet, instructions are not specific on how to dry endoscopes. There is lack of data supporting efficacy of current drying practices, due to limitations in determining channel dryness.

METHODS

Novel endoscope test articles were used to evaluate the effectiveness of alcohol flush and hanging in an ambient endoscope storage cabinet. Prepared test articles were hung in a storage cabinet for 5 days and visually inspected for residual liquid. The procedure for preoperative inspection of endoscopic systems was performed to determine the procedure's efficacy for removing residual liquid. Then, testing was performed to assess the impact of pressure, residual liquid type and route of air application on time to dry using compressed air.

RESULTS

Alcohol flush followed by hanging in an ambient storage cabinet was not effective for drying endoscope channels, and residual liquid was not completely removed after performing the steps of the preoperative inspection of endoscopic channels. The factors impacting effective compressed air drying were channel dependent. For some channels, alcohol increased the time to dry.

CONCLUSIONS

Endoscope drying is complex; borescope evaluation does not ensure a dry device.

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.

The Effectiveness of Drying on Residual Droplets, Microorganisms, and Biofilms in Gastrointestinal Endoscope Reprocessing: A Systematic Review

BACKGROUND

Despite endoscope reprocessing, residual droplets remain in gastrointestinal endoscope working channels. Inadequate drying of gastrointestinal endoscope working channels may promote microbial reproduction and biofilm formation, increasing the risk of infection in patients. This review was designed to provide the current status of gastrointestinal endoscope drying, emphasize the importance of gastrointestinal endoscope drying, and evaluate the effectiveness of different drying methods of gastrointestinal endoscope in reducing residual droplets and microbial growth risk.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting checklist. The PubMed, Web of Science, Medline, EMBASE, EBSCO, CNKI, CQVIP, and Wanfang Data databases were searched from 2010 to 2020 to identify eligible articles focused on methods of gastrointestinal endoscope drying and the status of endoscope drying. The following key points were analyzed: type of intervention, amount of residual droplets, major microbial types, and effectiveness of biofilm intervention. JBI quality assessment tool was used to determine bias risk for inclusion in the article.

RESULTS

This review included twelve articles. Two of the articles reported lack of drying of gastrointestinal endoscopes while the other ten reported residual droplets, microbial growth, and biofilm formation after different methods of drying. Four articles reported 0 to 4.55 residual droplets; four articles reported that the main microbial types were cocci and bacilli, most commonly Staphylococcus, Escherichia coli, Bacillus maltophilia, and Pseudomonas aeruginosa; and two reported that drying could effectively reduce biofilm regeneration. The type of intervention is as follows: automatic endoscopy reprocessor (AER), manual compressed air drying, and the Dri-Scope Aid for automatic drying and drying cabinet.

CONCLUSIONS

While endoscope reprocessing may not always be effective, an automatic endoscope reprocessor plus the Dri-Scope Aid with automatic drying over 10 min or storage in a drying cabinet for 72 h may be preferred.

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.

Novel Algorithms for Reprocessing, Drying and Storing Endoscopes

After outbreaks of duodenoscope-transmitted infection with multidrug-resistant organisms, it has become clear that institutions must optimize their endoscope reprocessing programs. Standard endoscope reprocessing practices may not represent the ideal approach for preventing transmission of infection related to endoscopy. We discuss multiple approaches to enhance and optimize reprocessing, drying, and storage of standard duodenoscopes. The optimal enhanced duodenoscope reprocessing modality remains to be determined. Acknowledging the challenges and limitations in effectively reprocessing duodenoscopes, the FDA issued a safety communiqué recommending transitioning to either single use disposable duodenoscopes or duodenoscopes with innovative designs that allow more effective reprocessing.

GIE Editorial Board top 10 topics: advances in GI endoscopy in 2019

The American Society for Gastrointestinal Endoscopy's GIE Editorial Board reviewed original endoscopy-related articles published during 2019 in Gastrointestinal Endoscopy and 10 other leading medical and gastroenterology journals. Votes from each individual member were tallied to identify a consensus list of 10 topic areas of major advances in GI endoscopy. Individual board members summarized important findings published in these 10 areas of disinfection, artificial intelligence, bariatric endoscopy, adenoma detection, polypectomy, novel imaging, Barrett's esophagus, third space endoscopy, interventional EUS, and training. This document summarizes these "top 10" endoscopic advances of 2019.

SpyGlass application for duodenoscope working channel inspection: Impact on the microbiological surveillance

BACKGROUND

Patient-ready duodenoscopes were designed with an assumed contamination rate of less than 0.4%; however, it has been reported that 5.4% of clinically used duodenoscopes remain contaminated with viable high-concern organisms despite following the manufacturer’s instructions. Visual inspection of working channels has been proposed as a quality control measure for endoscope reprocessing. There are few studies related to this issue.

AIM

To investigate the types, severity rate, and locations of abnormal visual inspection findings inside patient-ready duodenoscopes and their microbiological significance.

METHODS

Visual inspections of channels were performed in 19 patient-ready duodenoscopes using the SpyGlass visualization system in two endoscopy units of tertiary care teaching hospitals (Tri-Service General Hospital and National Taiwan University Hospital) in Taiwan. Inspections were recorded and reviewed to evaluate the presence of channel scratches, buckling, stains, debris, and fluids. These findings were used to analyze the relevance of microbiological surveillance.

RESULTS

Seventy-two abnormal visual inspection findings in the 19 duodenoscopes were found, including scratches (n = 10, 52.6%), buckling (n = 15, 78.9%), stains (n = 14, 73.7%), debris (n = 14, 73.7%), and fluids (n = 6, 31.6%). Duodenoscopes > 12 mo old had a significantly higher number of abnormal visual inspection findings than those ≤ 12 mo old (46 findings vs 26 findings, P < 0.001). Multivariable regression analyses demonstrated that the bending section had a significantly higher risk of being scratched, buckled, and stained, and accumulating debris than the insertion tube. Debris and fluids showed a significant positive correlation with microbiological contamination (P < 0.05). There was no significant positive Spearman’s correlation coefficient between negative bacterial cultures and debris, between that and fluids, and the concomitance of debris and fluids. This result demonstrated that the presence of fluid and debris was associated with positive cultures, but not negative cultures. Further multivariate analysis demonstrated that fluids, but not debris, is an independent factor for bacterial culture positivity.

CONCLUSION

In patient-ready duodenoscopes, scratches, buckling, stains, debris, and fluids inside the working channel are common, which increase the microbiological contamination susceptibility. The SpyGlass visualization system may be recommended to identify suboptimal reprocessing.

Impact of wet storage and other factors on biofilm formation and contamination of patient-ready endoscopes: a narrative review

The 2019 U.S. Food and Drug Administration report indicates that the clinical studies undertaken by the 3 main GI endoscope manufacturers demonstrate 5.4% of patient-ready duodenoscopes remain culture positive for high-concern organisms. The root causes of this persistent contamination are poorly understood. The objectives of this review include summarizing (1) the impact of inadequate manual cleaning and inadequate drying during storage on the formation of build-up biofilm in endoscope channels, (2) the impact of defoaming agents used during patient procedures on drying efficacy, (3) the data showing the importance of build-up biofilm on persistent microbial survival, and (4) the potential impact of implementation of a quality systems approach in GI endoscopy reprocessing.

Recovery of Curvularia mold from a duodenoscope after reprocessing in accordance with the manufacturer's cleaning protocol

In 2018, the Food and Drug Administration/Centers for Disease Control and Prevention revised protocols for surveillance sampling and cultures of duodenoscopes. We describe the recovery of the mold Curvularia from a duodenoscope processed according to the manufacturer's instructions using this revised sampling process. To our knowledge, this is the first time a mold has been recovered from a duodenoscope after following the Food and Drug Administration/Centers for Disease Control and Prevention protocol. This suggests that manufacturer's recommendation for scope reprocessing may be insufficient to adequately remove mold from these scopes.

Bronchoscope-related Pseudomonas aeruginosa pseudo-outbreak attributed to contaminated rinse water

BACKGROUND

Increased percentage of Pseudomonas aeruginosa from bronchoalveolar lavage fluid of patients in June 2016 was observed. P aeruginosa were also obtained from flexible bronchoscope and rinse water in the microbiological surveillance in June 2016.

METHODS

Reprocessing procedure of bronchoscope was assessed, and environmental samples were collected. P aeruginosa isolates recovered from bronchoalveolar lavage fluid of patients between May and September 2016 and environment were characterized using multilocus sequence typing and pulsed-field gel electrophoresis.

RESULTS

A novel multilocus sequence type (ST) of P aeruginosa was defined as ST 2387. ST671 and ST 2387 were both cultured from bronchoscopes and connecting tube in manual reprocessing cleaning equipment. One strain from a patient was indistinguishable from the clones obtained from the bronchoscope and connecting tube revealed by pulsed-field gel electrophoresis. Two strains from 2 patients from the burn intensive care unit were identical, and highly related to 2 other strains from the burn intensive care unit. The persistence of P aeruginosa in bronchoscopes, connecting tubes, and final rinse water was terminated by replacement of the connecting tube.

CONCLUSIONS

We report a pseudo-outbreak of P aeruginosa associated with bronchoscope, for which connecting tube was the hidden reservoir for contaminating bronchoscopes. This highlights that effective measures are needed to control the bacterial load in final rinsing water to protect reusable equipment from contamination in reprocessing and cleaning.

Endoscope reprocessing: Comparison of drying effectiveness and microbial levels with an automated drying and storage cabinet with forced filtered air and a standard storage cabinet

BACKGROUND

Automated drying may help prevent endoscopically transmitted infections. We aimed to assess the efficacy of an automated drying and storage cabinet compared to a standard storage cabinet in achieving endoscope dryness postreprocessing and in reducing the risk of microbial growth.

METHODS

Drying times of bronchoscopes, colonoscopes, and duodenoscopes using 2 drying platforms (an automated drying and storage cabinet vs a standard storage cabinet) were measured using cobalt chloride paper. Drying assessments occurred at: 30 minutes, 1 hour, 2 hours, 3 hours, and 24 hours. A simple linear regression analysis compared rates of microbial growth after inoculation with Pseudomonas aeruginosa following high-level disinfection at: 0, 3 hours, 12 hours, 24 hours, and 48 hours.

RESULTS

Using the automated drying and storage cabinet, internal channels were dry at 1 hour and external surfaces at 3 hours in all endoscopes. With the standard storage cabinet, there was residual internal fluid at 24 hours, whereas external surfaces were dry at 24 hours. For bronchoscopes, colonoscopes, and duodenoscopes, the standard cabinet allowed for an average rate of colony forming unit growth of 8.1 × 10⁶ per hour, 8.3 × 10⁶ per hour, and 7.0 × 10⁷ per hour, respectively; the automated cabinet resulted in colony forming unit growth at an average rate of -28.4 per hour (P = .02), -38.5 per hour (P = .01), and -200.2 per hour (P = .02), respectively.

CONCLUSIONS

An automated cabinet is advantageous for rapid drying of endoscope surfaces and in reducing the risk of microbial growth postreprocessing.

Gastrointestinal Endoscopy Editorial Board top 10 topics: advances in GI endoscopy in 2018

The American Society for Gastrointestinal Endoscopy's Gastrointestinal Endoscopy Editorial Board reviewed original endoscopy-related articles published during 2018 in Gastrointestinal Endoscopy and 10 other leading medical and gastroenterology journals. Votes from each individual member were tallied to identify a consensus list of 10 topic areas of major advances in GI endoscopy. Individual board members summarized important findings published in these 10 areas of adenoma detection, bariatric endoscopy, EMR/submucosal dissection/full-thickness resection, artificial intelligence, expandable metal stents for palliation of biliary obstruction, pancreatic therapy with lumen-apposing metal stents, endoscope reprocessing, Barrett's esophagus, interventional EUS, and GI bleeding. This document summarizes these "Top 10" endoscopic advances of 2018.

Medical instrument reprocessing: current issues with cleaning and cleaning monitoring

The complexity of medical devices has increased over the past 10 years, and outbreaks of infections due to contaminated devices have focused attention on the need to adequately clean medical devices in order to ensure the adequacy of disinfection and sterilization. There has been a paradigm shift in reprocessing of medical devices, with increased emphasis on a quality management systems approach that requires validated cleaning instructions from manufacturers and ongoing monitoring by reprocessing personnel to ensure adequacy of cleaning. This article reviews the current issues related to medical device reprocessing and summarizes the approaches used for monitoring cleaning efficacy for surgical instruments and flexible endoscopes.

Biofilms on instruments and environmental surfaces: Do they interfere with instrument reprocessing and surface disinfection? Review of the literature

There is a growing appreciation for the role of biofilm-embedded microbes in many different aspects of infection transmission. The format of biofilm includes traditional hydrated biofilm, build-up biofilm, and dry surface biofilm. The objectives of this article are to discuss how traditional biofilm differs from build-up biofilm and dry surface biofilm, and to review the evidence supporting infection transmission from biofilm that accumulates in reprocessed instruments and from dry biofilm that forms environmental reservoirs.