Infectious diseases linked to cross-contamination of flexible endoscopes

Sampling methods for flexible endoscopes without a working channel: a scoping review

BACKGROUND

A diagnostic flexible laryngoscopy using a flexible endoscope (FE) without a working channel can become contaminated when inserted through the nose to inspect the throat. Microbiological surveillance is necessary to ensure adequate reprocessing. A lack of knowledge exists about the most accurate way to assess microbiological contamination on the surface of FEs without a working channel. A scoping review of research on sampling techniques for FEs without a working channel was done to identify frequently used sampling techniques and to determine the best way to assess microbiological contamination.

METHODS

PubMed, Embase, Cochrane Library, and CINAHL databases were searched. Data related to the sampling technique and bacterial contamination were extracted.

RESULTS

Twelve of the 378 studies met the inclusion criteria. None compared sampling techniques, most studies investigated the efficacy of several disinfection methods. Retrieved sampling techniques were immersion, swabbing, and wiping. Immersion and wiping could detect bacterial contamination on contaminated FEs without a working channel. Two out of six studies using a swabbing method found bacterial contamination on contaminated FEs without a working channel. Three studies using the swabbing method detected bacterial contamination after disinfection. One study did not retrieve microorganisms after disinfection using the swabbing method.

CONCLUSIONS

Three different sampling techniques were extracted: immersion, wiping, and swabbing, which could all detect microbiological contamination on contaminated FEs without a working channel. However, this scoping review identified significant gaps in literature. Additional research is needed to determine the best sampling technique(s) for FEs without a working channel to detect microbiological contamination.

Capsule robots for the monitoring, diagnosis, and treatment of intestinal diseases

Current evidence suggests that the intestine as the new frontier for human health directly impacts both our physical and mental health. Therefore, it is highly desirable to develop the intelligent tool for the enhanced diagnosis and treatment of intestinal diseases. During the past 20 years, capsule robots have opened new avenues for research and clinical applications, potentially revolutionizing human health monitor, disease diagnosis and treatment. In this review, we summarize the research progress of edible multifunctional capsule robots in intestinal diseases. To begin, we introduce the correlation between the intestinal microbiome, intestinal gas and human diseases. After that, we focus on the technical structure of edible multifunctional robots. Subsequently, the biomedical applications in the monitoring, diagnosis and treatment of intestinal diseases are discussed in detail. Last but not least, the main challenges of multifunctional capsule robots during the development process are summarized, followed by a vision for future development opportunities.

Tolerance of Pseudomonas oleovorans biofilms to disinfectants commonly used in endoscope reprocessing?

Reprocessing failure of endoscopes may result in outbreaks of serious infections in vulnerable patients caused by Gram-negative bacteria. P. oleovorans (PSOL) was detected in 6 automated endoscope washer-disinfectors (AEWDs) in two reprocessing units during routine check and probing for quality control. Ten endoscopes were probed yielding the growth of PSOL. Two different PSOL strains were identified by genotyping. Biofilms and planktonic cells of both PSOL (N = 2) and of Pseudomonas aeruginosa PAO1 as reference were incubated with increased disinfectant concentrations modelling the disinfection process in the AEWD. PSOL in planktonic form was eradicated by GLUT1% (1 g/100 g) at 55 °C. GLUT at a higher concentration of 3 % resulted in the eradication of PSOL biofilms at 25 °C. The persistent growth of PSOL in quality controls indicates inadequate disinfection. Increase of the concentration of GLUT would be an option to eradicate PSOL. However, increasing the concentration of GLUT may lead to corrosion of the sensible instruments and toxic side-effects in patients. Further investigation on disinfectant type and concentration, the reservoir of contamination and defining additional disinfection steps are warranted.

Current management status of cleaning and disinfection for gastrointestinal endoscopy: a meta-analysis

Objective This study aimed to evaluate the current status of cleaning and disinfection management for digestive endoscopy, provide data for standardization processing techniques, and improve the quality of cleaning and disinfection. Methods Two reviewers independently and comprehensively searched the PubMed, Cochrane Library, EMBASE, Web of Science, CNKI, Wanfang, and CBM databases on February 1, 2023. The inclusion and exclusion criteria were strictly followed during the literature survey and data extraction. All observational studies detailing the current cleaning and disinfection management status for digestive endoscopy in hospitals were included. Meta-analysis was performed using STATA 16.0 software. Results After removing different articles, the meta-analysis finally included 54 articles associated with multiple countries. The authors favor auditing staffers to confirm compliance with guidelines. The meta-analysis results indicated a configuration rate of 76% (95% CI: 68-83%) for separate rooms designated for reprocessing; 79% (95% CI: 72-84%) for reprocessing rooms with adequate ventilation; 30% (95% CI: 24-36%) for automated endoscope washer-disinfectors; 68% (95% CI: 55-81%) for complete protective equipment usage; 90% (95% CI: 83-95%) for the configuration rate of endoscope and accessory storage cabinets; 50% (95% CI: 38-61%) for changing enzymatic-type detergents after each use; 51% (95% CI: 30-71%) for the use of purified or sterilized water for final rinsing; 80% (95% CI: 70-88%) for monitoring disinfectant concentration; 87% (95% CI: 80-93%) for microbial monitoring; and 44% (95% CI: 26-62%) for the usage of protective equipment. Conclusion The configuration of the automated endoscope washer-disinfector, non-standard cleaning and disinfection procedures, and a lack of occupational protection awareness among personnel responsible for cleaning and disinfecting digestive endoscopy were all apparent issues. It was suggested that all departments enhance their levels of management and supervision, standardize reprocessing procedures and quality control details, upgrade hardware facilities and spatial layouts, reinforce personnel training, and increase staff awareness of nosocomial infection risks.

Assessment of Ultraviolet-C Light for Sterilization of Hysteroscopy Instruments

Objective To evaluate the sterilization efficacy of hysteroscopy instruments using ultraviolet C (UV-C) light at a wavelength of 259 nm in the Endoscopic Diagnostic Center of the National Institute of Perinatology. Methods Consecutive patients undergoing office hysteroscopy via the Bettochi vaginoscopy technique were included, excluding those with conditions such as viable intrauterine pregnancy or acute pelvic infection. Samples were collected from six designated sites of the hysteroscope, including the inner sheath, internal holes of the inner sheath, lens, graspers, scissors, and outer sheath. Initially, samples were taken after the first sterilization using a LAOKEN LK/MJG-150 Plasma Sterilizer (Chengdu, China). Next, samples were collected after the routine use of the hysteroscope in the office setting to confirm contamination. Subsequently, a new set of samples were taken after a 20-minute UV-C sterilization cycle with the EsteriUV device. Results The initial sterilization achieved a 96.73% sterilization rate, with ten samples testing positive for Staphylococcus coagulase-negative. Post-hysteroscopy, contamination increased significantly. Afterward, UV-C sterilization achieved a 96.08% sterilization rate, with 11 samples positive for Staphylococcus coagulase-negative and one for Streptococcus anginosus (p=0.66). No clinical infections were reported in any patient within one-month post-procedure. Conclusion UV-C light is a viable alternative for hysteroscopy instrument sterilization, demonstrating comparable efficacy to conventional methods. Further studies are recommended to optimize UV-C parameters for enhanced sterilization efficiency.

A multicenter study comparing the bacterial reduction on flexible endoscopes without a working channel between UV-C light disinfection versus standard endoscope Washer Disinfection: a randomized controlled trial

BACKGROUND

To prevent cross-contamination between patients, adequate reprocessing is necessary when using flexible endoscopes (FEs) without a working channel. The current reprocessing process using an Endoscope Washer Disinfector (EWD) is time-consuming. Ultraviolet light group C (UV-C) exposition is an alternative and fast disinfection method and has previously been shown to adequately reduce Colony Forming Units (CFUs) on FEs without a working channel. The objective of this study was to examine whether UV-C light is as effective in reducing CFUs on contaminated FEs without a working channel compared to the EWD.

METHODS

FEs without a working channel were collected in three different Otorhinolaryngology Departments in the Netherlands. After pharyngolaryngoscopy, a manual pre-cleaning with tap water was performed and a culture was collected by rolling the distal 8-10 cm of the FE over an agar plate. Next, the FE was randomly assigned to be disinfected with UV-C light (D60) or the EWD (gold standard). After disinfection, another culture was taken. The primary outcome was microbiological contamination, defined by Colony Forming Units (CFU).

RESULTS

600 FEs without a working channel were randomized. After clinical use and manual pre-cleaning, 239/300 (79.7%) FEs in the UV-C group and 262/300 (87.3%) FEs in the EWD group were contaminated (i.e., > 0 CFU). FEs without culture confirmed contamination were excluded from further analysis. After UV-C light disinfection, 195/239 (81.6%) FEs showed 0 CFUs, compared to 187/262 (71.4%) FEs disinfected with the EWD (p < 0.01). A multivariate logistics regression analysis showed an increased odds of 0 CFUs when using UV-C light (OR 1.83, 95% CI 1.19-2.79; p < 0.01), conditional on participating hospitals and types of FE.

CONCLUSIONS

UV-C light disinfection of FEs without a working channel appears more effective in reducing CFUs compared to the EWD and might be a good alternative disinfection method.

TRIAL REGISTRATION

Not applicable.

Comparison of utility and organizational impact of reusable and single-use rhinolaryngoscopes in a tertiary otorhinolaryngology department

Background

Flexible rhinolaryngoscopes are an important tool in otolaryngology. In recent years, single-use rhinolaryngoscopes (SURLs), which have been developed as an alternative to reusable scopes (RRLs), offer various advantages including less risk of contamination and elimination of the need for cleaning and reprocessing between procedures. This study aimed to compare procedure efficiency, organizational impact, and economic impact between SURLs and RRLs used for elective procedures conducted outside the otorhinolaryngology department in the hospital environment.

Methods

In this randomized prospective study, either type of endoscope was tested by on-call otolaryngologists over a total of twelve weeks. The organizational impact was investigated using a quantitative research design. All categories of stakeholders responded to specific surveys based on profession; these included doctors (n = 13), those in managerial positions (n = 3), and other healthcare staff including technicians and nurses (n = 11). A micro-costing approach was used to evaluate resource utilization and cost of services. The trial was uploaded to clinicaltrials.gov (ID number: NCT0519821, https://clinicaltrials.gov/study/NCT05198219?intr=rhinolaryngo&rank=1).

Results

Overall, 14 and 12 procedures were performed using the SURLs and RRLs, respectively. No significant differences were observed between the endoscopes in terms of procedure duration, reported image quality, or maneuverability. The SURLs were significantly superior in terms of four organizational impact parameters, namely, modes of cooperation and communication, vigilance and monitoring methods, working conditions and safety, and logistics. The estimated per-procedure cost of the RRLs was SEK 536 (€ 34,68).

Conclusion

The cost and effectiveness of RRLs and SURLs is influenced by the healthcare setting, procedure volume, and duration of device use. The adoption of SURLs can improve safety, streamline processes, and potentially reduce the risk of disease transmission.

Whole-genome sequencing establishes persistence of biofilm-associated Pseudomonas aeruginosa detected from microbiological surveillance of gastrointestinal endoscopes

BACKGROUND

An increased incidence of Pseudomonas aeruginosa in microbiological surveillance (MS) cultures from gastrointestinal endoscopes was detected between March 2020 and March 2023 in Tan Tock Seng Hospital Singapore.

AIM

To describe the use of whole-genome sequencing (WGS) in this investigation.

METHODS

WGS was performed for all P. aeruginosa isolates with pairwise comparison of isolates to assess for genomic linkage. Comprehensive review of reprocessing practices and environmental sampling was performed.

FINDINGS

Twenty-two P. aeruginosa isolates were detected from endoscopic MS cultures. Fifteen (68%) isolates were available for WGS. Eighteen pairwise comparisons of isolates were made, of which 10 were found to be genomically linked. One endoscope had P. aeruginosa repeatedly cultured from subsequent MS that were genomically linked and persistent despite repeat endoscopic reprocessing, establishing the persistence of biofilm that could not be eradicated with routine reprocessing. All P. aeruginosa isolates cultured from other different endoscopes were genetically distinct. Investigation into reprocessing practices revealed the use of air/water valves connected to endoscopes during clinical use. Inspection of these valves revealed the presences of cracks and tears. All other environmental samples were negative.

CONCLUSION

The WGS findings helped to deprioritize common source contamination and supported the hypothesis of biofilm build-up within endoscopes, leading to repeatedly positive MS cultures that were genomically linked. This was possibly related to incomplete reprocessing of the damaged air/water valves, resulting in biofilm build-up. All faulty valves were changed and subsequently cleaned separately with ultrasonic cleaning followed by sterilization which resolved this incident.

Microbiological evaluation of ultraviolet C light-emitting diodes for disinfection of medical instruments

Background

Despite the many guidelines for reprocessing of medical instruments, challenges persist such as microbial resistance to biocides, corrosive effects on materials, and time-consuming reprocessing procedures. Ultraviolet (UV) C light-emitting diode (LED) chambers might provide a solution but the integration in healthcare is still in its infancy. Here, we evaluated the efficacy of a novel ZAPARAY™ UVC LED chamber as a time and energy-efficient alternative for reprocessing of medical instruments for which current disinfection protocols exhibit limitations.

Methods

We verified the disinfection efficacy of the UVC LED chamber on a Petri dish and contaminated several medical devices with Staphylococcus aureus ATCC 25923. The bacterial reduction was assessed after 5 min of UVC LED exposure. Additionally, we investigated the impact of rinsing before UVC exposure.

Results

We demonstrated a bacterial reduction of 9 log10 on a Petri dish. Non-rinsed dental tools exhibited varied reduction levels ranging from a 3.23 log10 to a 6.25 log10 reduction. Rinsing alone yielded an average reduction of 2.7 log10 and additional UVC exposure further reduced the bacterial load by an average of 3.65 log10. We showed an average 4.90 log10 reduction on thermistors, 2 log10 or less on orthodontic pliers, and no reduction on handpieces.

Conclusions

This study demonstrates that UVC LED chambers may be used as a standardized substitute for specific (manual) disinfection procedures of certain medical devices, offering a time-efficient and more sustainable alternative. However, its use should be preceded by efficacy testing for each specific type of instrument.

Environmental Impact of Flexible Cystoscopy: A Comparative Analysis Between Carbon Footprint of Isiris® Single-Use Cystoscope and Reusable Flexible Cystoscope and a Systematic Review of Literature

Introduction: There is an absence of data on the environmental impact of single-use flexible cystoscopes. We wanted to review the existing literature about carbon footprint of flexible cystoscopy and analyze the environmental impact of the Isiris® (Coloplast©) single-use flexible cystoscope compared to reusable flexible cystoscopes. Methods: First, a systematic review on single-use and reusable cystoscope carbon footprint was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Second, carbon footprints of Isiris single-use flexible cystoscope and reusable cystoscope were analyzed and compared. Life cycle of the single-use flexible cystoscope was divided in three steps: manufacturing, sterilization, and disposal. For the reusable cystoscope, several steps were considered to estimate the carbon footprint over the life cycle: manufacturing, washing/sterilization, repackaging, repair, and disposal. For each step, the carbon footprint values were collected and adapted from previous comparable published data on flexible ureteroscope. Results: The systematic literature review evidenced total carbon emissions within a range of 2.06 to 2.41 kg carbon dioxide (CO2) per each use of single-use flexible cystoscope compared to a wide range of 0.53 to 4.23 kg CO2 per each case of reusable flexible cystoscope. The carbon footprint comparative analysis between Isiris single-use flexible cystoscope and reusable cystoscope concluded in favor of the single-use cystoscope. Based on our calculation, the total carbon emissions for a reusable flexible cystoscope could be refined to an estimated range of 2.40 to 3.99 kg CO2 per case, depending on the endoscopic activity of the unit, and to 1.76 kg CO2 per case for Isiris single-use cystoscope. Conclusion: The results and our systematic literature review demonstrated disparate results depending on the calculation method used for carbon footprint analysis. However, the results tend rather toward a lower environmental impact of single-use devices. In comparison to a reusable flexible cystoscope, Isiris compared favorably in terms of carbon footprint.

The Evolution of Spinal Endoscopy: Design and Image Analysis of a Single-Use Digital Endoscope Versus Traditional Optic Endoscope

Spinal endoscopy has evolved significantly since its inception, offering minimally invasive solutions for various spinal pathologies. This study introduces a promising innovation in spinal endoscopy-a single-use digital endoscope designed to overcome the drawbacks of traditional optic endoscopes. Traditional endoscopes, despite their utility, present challenges such as fragility, complex disinfection processes, weight issues, and susceptibility to mechanical malfunctions. The digital endoscope, with its disposable nature, lighter weight, and improved image quality, aims to enhance surgical procedures and patient safety. The digital endoscope system comprises a 30-degree 1000 × 1000 pixel resolution camera sensor with a 4.3 mm working channel, and LED light sources replacing optical fibers. The all-in-one touch screen tablet serves as the host computer, providing portability and simplified operation. Image comparisons between the digital and optic endoscopes revealed advantages in the form of increased field of view, lesser distortion, greater close-range resolution, and enhanced luminance. The single-use digital endoscope demonstrates great potential for revolutionizing spine endoscopic surgeries, offering convenience, safety, and superior imaging capabilities compared to traditional optic endoscopes.

Is ultraviolet light disinfection fit to be the future standard for the disinfection of flexible endoscopes without a working channel?

OBJECTIVE

To investigate colony-forming unit (CFU) reduction on contaminated flexible endoscopes (FEs) without a working channel after UV-C light disinfection, compared to the current disinfection method with the endoscope washer disinfector (EWD).

DESIGN, SETTING AND PARTICIPANTS

After pharyngolaryngoscopy, a manual pre-cleaning with tap water was performed. A culture was then collected by rolling the distal 8-10 cm of the FE over an Agar plate. The FE was disinfected using the D60 (60-s disinfection process with UV-C light) or the EWD (gold standard reprocessing process with water and chemicals). Another culture was then taken. After incubation, a CFU count was performed.

RESULTS

A total of 200 FEs without a working channel were divided equally between the two disinfection groups. After clinical use and manual pre-cleaning, 84 of the 100 (84.0%) (UV-C light group) and 79 of the 100 (79.0%) (EWD) FEs were contaminated with at least 1 CFU. FEs that showed no contamination after use were excluded from further analysis. After disinfection with UV-C light, 72 (85.7%) FEs showed no contamination (i.e., 0 CFUs) versus 66 (83.5%) FEs after reprocessing with the EWD.

CONCLUSION

There is no difference in CFUs reduction on contaminated FEs without a working channel between UV-C light disinfection and the current gold standard, the EWD.

Time Efficiency and Performance of Single-Use vs Reusable Cystoscopes: A Randomized Benchtop and Simulated Clinical Assessment

Introduction: A flexible cystoscope is an indispensable tool for urologists, facilitating a variety of procedures in both the operating room and at bedside. Single-use cystoscopes offer benefits including accessibility and decreased burden for reprocessing. The aims of this study were to compare time efficiency and performance of single-use and reusable cystoscopes. Methods: Ten new Ambu® aScope™ 4 Cysto single-use and two Olympus CYF-5 reusable cystoscopes were compared in simulated bedside cystoscopy and benchtop testing. Ten urologists performed simulated cystoscopy using both cystoscopes in a randomized order. Times for supply-gathering, setup, cystoscopy, cleanup, and cumulative time were recorded, followed by a Likert feedback survey. For benchtop assessment, physical, optical, and functional specifications were assessed and compared between cystoscopes. Results: The single-use cystoscope demonstrated shorter supply-gathering, setup, cleanup, and cumulative times (824 vs 1231 seconds; p < 0.05) but a comparable cystoscopy time to the reusable cystoscope (202 vs 212 seconds; p = 0.32). The single-use cystoscope had a higher image resolution, but a narrower field of view. Upward deflection was greater for the single-use cystoscope (214.50° vs 199.45°; p < 0.01) but required greater force (2.5 × ). The working channel diameter and irrigation rate were greater in the reusable cystoscope. While the single-use cystoscope lacked tumor enhancing optical features, it had higher Likert scale scores for Time Efficiency and Overall Satisfaction. Conclusion: The single-use cystoscope demonstrates comparable benchtop performance and superior time efficiency compared to reusable cystoscopes. However, the reusable cystoscope has superior optical versatility and flow rate. Knowledge of these differences allows for optimal cystoscope selection based on procedure indication.

The Effectiveness of Ultraviolet Smart D60 in Reducing Contamination of Flexible Fiberoptic Laryngoscopes

OBJECTIVE

To compare the effectiveness of disinfection protocols utilizing a ultraviolet (UV) Smart D60 light system with Impelux™ technology with a standard Cidex ortho-phthalaldehyde (OPA) disinfection protocol for cleaning flexible fiberoptic laryngoscopes (FFLs).

METHODS

Two hundred FFLs were tested for bacterial contamination after routine use, and another 200 FFLs were tested after disinfection with one of four methods: enzymatic detergent plus Cidex OPA (standard), enzymatic detergent plus UV Smart D60, microfiber cloth plus UV Smart D60, and nonsterile wipe plus UV Smart D60. Pre- and post-disinfection microbial burden levels and positive culture rates were compared using Kruskal-Wallis ANOVA and Fisher's two-sided exact, respectively.

RESULTS

After routine use, approximately 56% (112/200) of FFLs were contaminated, with an average contamination level of 9,973.7 ± 70,136.3 CFU/mL. The standard reprocessing method showed no positive cultures. The enzymatic plus UV, microfiber plus UV, and nonsterile wipe plus UV methods yielded contamination rates of 4% (2/50), 6% (3/50), and 12% (6/50), respectively, with no significant differences among the treatment groups (p > 0.05). The pre-disinfection microbial burden levels decreased significantly after each disinfection technique (p < 0.001). The average microbial burden recovered after enzymatic plus UV, microfiber plus UV, and nonsterile wipe plus UV were 0.40 CFU/mL ± 2, 0.60 CFU/mL ± 2.4, and 12.2 CFU/mL ± 69.5, respectively, with no significant difference among the treatment groups (p > 0.05). Micrococcus species (53.8%) were most frequently isolated, and no high-concern organisms were recovered.

CONCLUSION

Disinfection protocols utilizing UV Smart D60 were as effective as the standard chemical disinfection protocol using Cidex OPA.

LEVEL OF EVIDENCE

NA Laryngoscope, 133:3512-3519, 2023.

A review on model-based and model-free approaches to control soft actuators and their potentials in colonoscopy

Colorectal cancer (CRC) is the third most common cancer worldwide and responsible for approximately 1 million deaths annually. Early screening is essential to increase the chances of survival, and it can also reduce the cost of treatments for healthcare centres. Colonoscopy is the gold standard for CRC screening and treatment, but it has several drawbacks, including difficulty in manoeuvring the device, patient discomfort, and high cost. Soft endorobots, small and compliant devices thatcan reduce the force exerted on the colonic wall, offer a potential solution to these issues. However, controlling these soft robots is challenging due to their deformable materials and the limitations of mathematical models. In this Review, we discuss model-free and model-based approaches for controlling soft robots that can potentially be applied to endorobots for colonoscopy. We highlight the importance of selecting appropriate control methods based on various parameters, such as sensor and actuator solutions. This review aims to contribute to the development of smart control strategies for soft endorobots that can enhance the effectiveness and safety of robotics in colonoscopy. These strategies can be defined based on the available information about the robot and surrounding environment, control demands, mechanical design impact and characterization data based on calibration.

In vitro activity of sanitizers against mono- and polymicrobial biofilms of C. parapsilosis and S. aureus

The emergence of disinfectant-resistant microorganisms poses a significant threat to public health. These resilient pathogens can survive and thrive in hospital settings despite routine disinfection practices, leading to persistent infections and the potential for outbreaks. In this study, we investigated the impact of 11 different commercial sanitizers at various concentrations and exposure times on biofilms consisting of clinical and nosocomial environmental isolates of Candida parapsilosis and Staphylococcus aureus. Among the sanitizers tested, 0.5% and 2.0% chlorhexidine (CLX), 10% polyvinyl pyrrolidone (PVP-I), a disinfectant based on quaternary ammonium compound (QAC), 2% glutaraldehyde, and 0.55% orthophthalaldehyde (OPA) demonstrated efficacy against both C. parapsilosis and S. aureus in monospecies and mixed biofilms. Analysis showed that 0.5% CLX and 10% PVP-I had fungicidal and bactericidal activity against all biofilms. However, the sanitizer based on QAC and 0.55% OPA proved to be bacteriostatic and fungicidal against both monospecies and mixed biofilms. In mixed biofilms, despite the last four sanitizers exerting fungicidal action, the reduction of fungal cells was approximately 4 log10 CFU/mL compared to monospecies biofilms, showing that the interaction provided more resistance of the yeast to the sanitizer. Formation of mixed biofilms in hospital settings can create an ecological niche that enhances the survival of pathogens against routine sanitization procedures. Therefore, effective sanitization practices, including regular cleaning with effective sanitizers, should be implemented to prevent C. parapsilosis/S. aureus biofilm formation in healthcare settings.

Bacterial contamination of endoscopist and assistant face visors during gastrointestinal endoscopy: a pilot study

Background and aim

During the COVID-19 pandemic, health workers' facial exposure to pathogens has been brought into focus. In this study, we aimed to determine the occurrence and degree of facial contamination to both endoscopists and their assistants during endoscopic procedures to help inform future safety measures.

Methods

Non-sterile visors worn by endoscopist, assistant and room control visors from 50 procedures were swabbed post procedure for culture. Procedure type, therapy, duration and evidence of visible visor contamination were recorded. After 48-hour incubation, all bacterial colonies were identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Organisms were classified into skin/environmental, oronasal and enteric.

Results

A total of 104 visors were available for assessment (93 staff; 11 control). In worn visors, skin/environmental flora were isolated from 70, oronasal flora from 8, and enteric flora from 3 with an average colony count of >9.5. Notably, bacteria of enteric origin (Escherichia coli and Enterobacter cloacae) were isolated from three worn visors. In room control, skin/environmental flora were isolated from seven and oronasal flora from one with average colony count of five. No room control visors grew enteric flora. Overall, 9.1% room control and 10.8% worn visors were contaminated with organisms that could possibly have originated from patients. However, enteric flora were only obtained from worn visors. No visors were visibly contaminated.

Conclusion

This pilot study demonstrates risk of contamination to faces of endoscopists and assistants. Larger studies are required to determine degree of risk and to give guidance on facial protection during gastrointestinal endoscopy.

A Single-Blind Study Testing the Preparation Accuracy of Bedside Precleaning Solutions Used for Flexible Endoscopes

Endoscopy-related pathogen transmission may occur if microorganisms are spread from patient to patient by contaminated equipment. Effective and safe endoscope reprocessing includes bedside precleaning, mechanical cleaning, high-level disinfection, storage, and drying. The aim of this research study was to observe and report on the variation in practice regarding the use of detergent for bedside precleaning of flexible gastrointestinal endoscopes. Endoscopy nurses working in the endoscopy unit at the Princess Alexandra Hospital, Australia, prepared four samples of detergent solution as per normal routine. Twenty-nine nurses participated providing in total 116 samples. There was a significant variation in detergent concentration. The detergent concentration variated between 2.00 and 288.20 ml/L ( M = 34.55, SD = 39.21). Two samples revealed lower concentrations than required. More than 25% of the samples contained at least a 10 times higher concentration than required (>40 ml/L). Current practice of bedside precleaning of gastrointestinal endoscopes was not deemed safe or cost-effective as it did not guarantee an adequate concentration of detergent. More precise methods to establish the required concentration of the bedside precleaning solution were introduced to improve practice.

Endoscope reprocessing: Retrospective analysis of 90,311 samples

Background and study aims The contamination level of ready-to-use endoscopes published in the literature varies from 0.4 % to 49.0 %. Unfortunately, the comparison and the interpretation of these results are quite impossible, given the limited number of samples and sites included and the differences observed between sampling, culturing methods, and interpretation criteria. Methods The objective of this retrospective study was to analyze the results of 90,311 endoscope samples collected between 2004 and 2021 in 490 private or public hospitals in France. Results Through the full test period, the mean ratio of endoscopes at the action level was 12.6 % (19.5 % including alert level). Of the endoscopy units, 23.0 % had a ratio of compliant endoscopes ≤ 70.0 %. The overall microbial quality of gastroscopes, duodenoscopes, and colonoscopes is improving year by year, whereas an opposite trend is observed for ultrasound endoscopes and bronchoscopes. In 2021, following French guidelines, 13.0 % of the endoscopes should have been quarantined and 8.1 % were at the alert level, meaning that the contamination level of 21.1 % of the endoscopes exceeded what was defined as a maximum acceptable value. Conclusions This study demonstrates that additional efforts, including implementation of microbial surveillance strategies using a standardized sampling method and periodic observational audits, must be made to improve the overall microbiological quality of endoscopes and reduce the risk associated with their use.

Evaluation of the Application Effect of a New Anti-reflux Water Injection Tube Device in the Prevention of the Contamination of Endoscopy Water Injection Bottles

BACKGROUND

Water delivery tube reflux during gastrointestinal endoscopy examination is widespread and it is the leading cause of water injection bottle pollution.

AIM

To evaluate the application effect of a new anti-reflux water injection tube device in preventing the contamination of endoscopy water injection bottles.

METHODS

A total of 520 cases received gastrointestinal endoscopy examination were included. Patients were randomly divided into the experimental and control group. The experimental group used the anti-reflux injection tube device to assist with water injection, and the control group used the ordinary delivery tube. After every five cases of gastrointestinal endoscopy, water from the injection bottles was collected. Visual inspection, crystalline violet staining, microbial culture, and microbial species analysis were performed to analyze the contamination state of the water samples.

RESULTS

The contamination rate in the experimental group was 5.66%, significantly lower than 76.47% in the control group. Crystalline violet staining confirmed that microorganisms existed in contaminated water samples. Microbiological culture results showed that the experimental group's undetectable rate of bacteria and fungi was 100%, significantly higher than that of the control group (19.61% for bacteria and 25.49% for fungi). The mean values of the total bacterial and fungal colonies of the control samples were 9.80 × 10⁶ cfu/ml and 9.18 × 10⁶ cfu/ml, respectively. The microbial species in the contaminated samples of the control group were Pseudomonas aeruginosa, Escherichia coli, and Proteus mirabilis.

CONCLUSION

The anti-reflux water injection tube device can effectively prevent the contamination of the endoscopy water injection bottles caused by the reflux of the ordinary water supply tube.

Life Cycle Assessment of Reusable and Disposable Cystoscopes: A Path to Greener Urological Procedures

BACKGROUND

The environmental impact of reusable and disposable devices is unclear; reuse is expected to reduce the carbon footprint, but the environmental impact of reprocessing of reusable devices is increasingly being questioned.

OBJECTIVE

The aim was to provide the first rigorous life cycle assessment of reusable and disposable flexible cystoscopes.

DESIGN, SETTING, AND PARTICIPANTS

We performed a life cycle assessment of reusable flexible cystoscopes and the aS4C single-use cystoscope (aScope; Ambu, Ballerup, Denmark). For the aScope, the complete lifespan of the scope was evaluated, including raw material extraction, material formulation, component production, product assembly, distribution, transportation after use, and final disposal. For reusable cystoscopes, we limited our analysis to their reprocessing, using a model consisting of standard high-level disinfection with peracetic acid. The environmental impact was evaluated by an independent third-party consulting company APESA (Technopole Hélioparc, Pau, France) dedicated to such risk assessments.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The environmental footprint of both cystoscopes was assessed using five environmental impact categories, namely, climate change, mineral resource depletion, ecotoxicity, acidification, and eutrophication. To perform the life cycle assessment, Simapro v9.3.3 software was used and the Ecoinvent v3.5 database was employed as the primary life cycle inventory database. A Monte Carlo analysis was used to account for the inherent uncertainty in life cycle inventory data and the variability in material and energy consumption for each type of flexible cystoscope.

RESULTS AND LIMITATIONS

By only comparing the disinfection reprocessing of reusable cystoscopes with the complete lifespan of the single-use cystoscope, the use of the aScope would allow a reduction of at least 33% in the climate change category, 50% in the mineral resources' depletion category, 51% in the ecotoxicity category, 71% in the acidification category, and 49% in the eutrophication category. Our results cannot be generalized to all health care facilities as we studied only one type of reprocessing method and one disposable flexible cystoscope.

CONCLUSIONS

Disinfection reprocessing of reusable cystoscopes was found to have a significantly larger environmental footprint and impact than the whole lifespan of the single-use cystoscope aScope.

PATIENT SUMMARY

Using a cradle-to-grave life cycle analysis, we showed that the environmental footprint of a flexible cystoscopy procedure can be reduced by using a disposable cystoscope instead of a reusable cystoscope.

Cost and Environmental Impact of Disposable Flexible Cystoscopes Compared to Reusable Devices

Objectives: To quantify the environmental impact and costs associated with flexible cystoscopy procedures from an institutional perspective, with particular attention for the comparison between disposable and reusable cystoscopes. Materials and Methods: This is a single-center retrospective study, including all flexible cystoscopies performed between 2020 and 2021 using reusable or single-use devices. The Ambu aS4C single-use cystoscope (Ballerup, Denmark) gradually replaced the reusable device in our center, with exclusive use from October 2021. Reprocessing costs for reusable cystoscopes were evaluated using a micro-costing approach. The environmental impact of reusable and disposable cystoscopes was assessed by the amount of waste and water consumed for each procedure. Results: A total of 1578 flexible cystoscopies using reusable cystoscopes were performed in 2020, and 550 cystoscopies were performed using the Ambu aS4C cystoscope from October 2021 to February 2022. The cost of flexible cystoscopy with a reusable and a disposable endoscope was €196 and €192, respectively. The amount of waste generated by reprocessing reusable and disposable cystoscopes was 800 and 200 g per procedure, respectively. Water consumption for sterilization of the reusable cystoscope was 60 L per procedure, whereas no water consumption was required with the Ambu aS4C cystoscope. A 100% Ambu aS4C cystoscope use would reduce waste generation and water consumption by 946.8 kg and 94.68 m3 per year. Conclusion: In this study, implementing a strategy of using 100% disposable cystoscopes was associated with similar costs and reduced waste generation and water consumption compared to reusable devices. Future studies are needed to compare the carbon footprint of these devices, through a comprehensive and rigorous life cycle assessment from manufacturing to recycling.

Micro-cost analysis of single-use vs. reusable cystoscopy in a single-payer healthcare system

INTRODUCTION

Single-use flexible diagnostic cystoscopy has recently been developed with comparable functionality to reusable cystoscopes. Prior studies have demonstrated considerable upfront costs of reusable cystoscopy. The objective of this study was to compare costs of reusable cystoscopy to single-use cystoscopy in a single-payer, socialized healthcare system.

METHODS

A retrospective micro-cost analysis of reusable cystoscopy in a combined inpatient and outpatient setting at a single institution was performed. The cost analysis was divided into capital, maintenance, reprocessing, and labor. Annual costs were averaged over two fiscal years. Costs were amortized over five- and 10-year bases as appropriate. The results were compared to theoretical costs of single-use cystoscopes.

RESULTS

There were 3415 annual average cystoscopy cases with 171 cases per reusable cystoscope. The capital, maintenance, reprocessing, and labor costs of reusable cystoscopy were $96 000, $99 867, $247 855, and $65 317, respectively. The total annual costs per case for reusable and single-use cystoscopy were $149.06 and $245.57, respectively. The costs of reusable cystoscopy decreased with the number of procedures per year and intersected the costs of single-use cystoscopes at 1265 procedures per year. All costs were calculated in Canadian dollars ($CAD).

CONCLUSIONS

The cost-effectiveness of reusable cystoscopes is dependent on cystoscopy volume due to considerable upfront costs. Single-use cystoscopes are more cost-effective if the total number of cases performed is less than 1265 per year. Additional investigation into the cost-effectiveness of single-use cystoscopes as supplements in the outpatient setting or primary endoscopes in inpatient/emergency settings should be performed.

Hybrid flexible ureteroscopy strategy in the management of renal stones - a narrative review

The introduction of single-use flexible ureteroscopes (suFURSs) in daily practice tends to overcome the main limitations of reusable ureteroscopes (reFURSs), in terms of high acquisition costs, maintenance, breakages and repairing costs, reprocessing and sterilization, as retrograde intrarenal surgery (RIRS) is promoted as first-line treatment of renal stones in most cases. A hybrid strategy implies having both instruments in the armamentarium of endourology and choosing the best strategy for cost-efficiency and protecting expensive reusable instruments in selected high-risk for breakage cases such as large stones of the inferior calyx, a steep infundibulopelvic angle or narrow infundibulum, or abnormal anatomy as in horseshoe and ectopic kidney. In terms of safety and efficiency, data present suFURSs as a safe alternative considering operating time, stone-free, and complication rates. An important aspect is highlighted by several authors about reusable instrument disinfection as various pathogens are still detected after proper sterilization. This comprehensive narrative review aims to analyze available data comparing suFURSs and reFURSs, considering economic, technical, and operative aspects of the two types of instruments, as well as the strategy of adopting a hybrid approach to selecting the most appropriate flexible ureteroscope in each case.

An outbreak of postoperative rapidly developing and multidrug-resistant Klebsiella pneumoniae urosepsis due to a contaminated ureteroscope

INTRODUCTION

Outbreaks caused by microorganisms contaminating the inside of rigid ureteroscopes are extremely rare. Some of these outbreaks, especially those caused by multidrug-resistant (MDR) infections, can cause serious problems, even death. Among these serious infections, we have no data about Klebsiellapneumoniae outbreaks caused by rigid ureteroscopes and their management and consequences.

Resisting disinfectants

van Dijk et al. discuss the potential for antimicrobial resistance as a consequence of disinfectant use. The authors advocate for the prudent use of disinfectants in all sectors of society.

Smart pills for gastrointestinal diagnostics and therapy

Ingestible smart pills have the potential to be a powerful clinical tool in the diagnosis and treatment of gastrointestinal disease. Though examples of this technology, such as capsule endoscopy, have been successfully translated from the lab into clinically used products, there are still numerous challenges that need to be overcome. This review gives an overview of the research being done in the area of ingestible smart pills and reports on the technical challenges in this field.

Sans Standardization: Effective Endoscope Reprocessing

Bronchoscopy is a commonly performed procedure within thoracic and critical care medicine. Modern bronchoscopes are technologically advanced tools made of fragile electronic components. Their design is catered to allow maximum maneuverability within the semi-rigid tracheobronchial tree. Effective cleaning and reprocessing of these tools can be a challenge. Although highly functional, the design poses several challenges when it comes to reprocessing. It is a very important step, and lapses in the procedure have been tied to nosocomial infections. The process lacks universal standardization; several organizations have developed their own recommendations. Data have shown that key stakeholders are not fully versed in the essentials of endoscope reprocessing. A significant knowledge gap exists between those performing bronchoscopy and those who are stewards of effective endoscope reprocessing. To service as a resource for bronchoscopists, this study summarizes the steps of effective reprocessing, details the important elements within a health-care facility that houses this process, and reviews some of the current data regarding the use of disposable endoscopes.

The application of plan, do, check, act (PDCA) quality management in reducing nosocomial infections in endoscopy rooms: It does work

BACKGROUND

The role of plan, do, check, act (PDCA) cycle quality management in reducing nosocomial infections in endoscopy rooms remains unclear; we aimed to evaluate the effects of PDCA in the nosocomial infections control of endoscopy rooms.

METHODS

This present study was a before and after design. The patients treated in our endoscopy room from 1 January 2019 to 31 December 2019 were included in the control group, which were managed according to current department practice. The patients from 1 January 2020 to 31 December 2020 were included in the PDCA group, which were managed according to PDCA cycle quality management including formulation of cleaning and disinfection process, establishment of an infection control team and improvement of inspection standards. The nosocomial infections of patients, the pass rate of medical staff's knowledge on the nosocomial infection and hand hygiene, the pass rate of disinfection of endoscope cavity and surface, the incidence of sharp injury and biological pollution were compared between two groups.

RESULTS

A total of 1020 patients were included, with 512 patients in PDCA group and 508 patients in the control group. The incidence of nosocomial infections in PDCA group was significantly lower than that of control group (0.98% vs. 2.76%, P = .002). The pass rate of medical staff's knowledge on the nosocomial infection and hand hygiene was significantly higher than that of control group (all P < .05). The pass rate of disinfection of endoscope cavity in PDCA group was significantly higher than that of control group (P = .037). The incidence of sharp injury and biological pollution in PDCA group were significantly lower than that of control group (all P < .05).

CONCLUSIONS

PDCA cycle management is beneficial to reduce the risk of nosocomial infection, enhance the awareness of infection control and reduce the risk of occupational exposure of medical staff in the endoscopy room.

Endorobots for Colonoscopy: Design Challenges and Available Technologies

Colorectal cancer (CRC) is the second most common cause of cancer death worldwide, after lung cancer (Sung et al., 2021). Early stage detection is key to increase the survival rate. Colonoscopy remains to be the gold standard procedure due to its dual capability to optically inspect the entire colonic mucosa and to perform interventional procedures at the same time. However, this causes pain and discomfort, whereby it requires sedation or anaesthesia of the patient. It is a difficult procedure to perform that can cause damage to the colonic wall in some cases. Development of new technologies aims to overcome the current limitations on colonoscopy by using advancements in endorobotics research. The design of these advanced medical devices is challenging because of the limited space of the lumen, the contorted shape, and the long tract of the large bowel. The force applied to the colonic wall needs to be controlled to avoid collateral effects such as injuries to the colonic mucosa and pain during the procedure. This article discusses the current challenges in the colonoscopy procedure, the available locomotion technologies for endorobots used in colonoscopy at a prototype level and the commercial products available.

Flexible Endoscopes: Terminal Sterilization and Impact to Patient Safety

Flexible endoscopes are implicated in deaths from healthcare-associated infections (HAIs), in particular antibiotic-resistant infections. This article analyzes whether terminal sterilization should be required as part of endoscope reprocessing to reduce or eliminate HAIs and thus improve patient safety. Reusable flexible endoscopes are processed to make them ready for clinical use by the processing department of the healthcare facility. Unlike most critical and semicritical medical devices, the final step of processing an endoscope is high-level disinfection and not terminal sterilization. This is because most flexible endoscopes come in contact with mucosal membranes (versus contact with direct blood stream) and cannot withstand sterilization. However, sterilization currently is performed by a small number of U.S. healthcare facilities on reusable flexible endoscopes with the belief that they are safer for use compared to flexible endoscopes that are high-level disinfected. Based on the analysis in this article, terminal sterilization is not a required or necessary step to eliminate HAIs.

Outcomes and Cost Evaluation Related to a Single-Use, Disposable Ureteric Stent Removal System: a Systematic Review of the Literature

PURPOSE OF REVIEW

To present the latest evidence related to the outcomes and cost of single-use, disposable ureteric stent removal system (Isiris).

RECENT FINDINGS

Our review suggests that compared to a reusable flexible cystoscope (re-FC), a disposable flexible cystoscope (d-FC) with built-in grasper (Isiris) significantly reduced procedural time and provided a cost benefit when the latter was used in a ward or outpatient clinic-based setting. The use of d-FC also allowed endoscopy slots to be used for other urgent diagnostic procedures. Disposable FCs are effective and safe for ureteric stent removal. They offer greater flexibility and, in most cases, have been demonstrated to be cost-effective compared to re-FCs. They are at their most useful in remote, low-volume centres, in less well-developed countries and in centres where large demand is placed on endoscopy resources.

Infection Prevention in the Neonatal Intensive Care Unit

Although many aspects of infection prevention and control (IPC) mirror institutional efforts, optimization of IPC practices in the neonatal intensive care unit requires careful consideration of its unique population and environment, addressed here for key IPC domains. In addition, innovative mitigation efforts to address challenges specific to limited resource settings are discussed.

Market Readiness for Single-Use Cystoscopes According to Urologists and Procurement Managers Worldwide

PURPOSE

Single-use endoscopes have been subjected to increase awareness in recent years, and several new single-use cystoscopes (eg Ambu® aScope 4 Cysto) have entered the market. However, the market readiness for such single-use cystoscopes remains unknown. This study investigates the worldwide market readiness for single-use cystoscopes among urologists and procurement managers (PMs) from Europe, Japan, and the US.

MATERIALS AND METHOD

An online survey using QuestionPro® was distributed to urologists and PMs in France, Germany, Italy, Japan, Spain, the UK, and the US between March 10, 2020 and July 14, 2020. All surveys were translated into the respective local language. Statistical analyses were performed using the software package Stata/SE version 16.1, StataCorp. Fisher's exact test was used to analyze categorical variables and simple linear regression was applied to continuous variables.

RESULTS

A total of 415 urologists and PMs completed the survey (343 [82.7%] urologists and 72 [17.3%] PMs). Seventy (16.9%) were from Japan, 100 (24.1%) were from the US, and 245 (59.0%) were evenly distributed across the following European countries: France, Germany, Italy, Spain, and the UK. On average, respondents indicated that they would consider converting to single-use in 44.5% of their cystoscopy procedures. Respondents anticipated significantly higher conversion (p<0.05) when they (1) used single-use ureteroscopes in their department, (2) were concerned about cystoscopy-related infection as a result of contaminated cystoscopes, (3) were members of their institution's value committee, or (4) considered cost-transparency to be important when purchasing cystoscopes.

CONCLUSION

This study investigated the marked readiness for single-use cystoscopes according to urologists and PMs worldwide. Respondents indicated a willingness to convert to single-use cystoscopes in nearly half (44.5%) of their cystoscopy procedures. Respondents that were concerned about cystoscopy-related infections as a result of contaminated cystoscopes indicated a significantly higher anticipated conversion rate (p<0.05).

UV light-based reprocessing of flexible endoscopes without working channel in Oto-Rhino-Laryngology: an effective method?

Background

Reprocessing of flexible endoscopes (FEs) is often expensive, time consuming, and becomes increasingly complex, due to rising demands of hygiene. After beneficial results in reprocessing of rigid endoscopes using Impelux™ UV-C light technology, we tested the same method for reprocessing of FEs without working channel.

Materials and methods

Testing was performed on FEs without working channel after routine clinical use (transnasal flexible endoscopy). Disinfection consisted of mechanical precleaning and 60 s exposure to Impelux™ UV-C light technology. Bacterial contamination was tested on 50 FEs before and after disinfection. Further 50 FEs regarding protein residuals. The absolute effectiveness of the D60 was tested on 50 test bodies (RAMS) with a standardized contamination of 10⁷ colony-forming units (CFU) of Enterococcus faecium.

Results

The FEs were contaminated with a high average value of 916.7 CFU (± 1057 CFU) after clinical usage. After reprocessing, an average contamination of 2.8 CFU (± 1.6) on 14% (n = 7) of the FEs was detected consisting of non-pathogenic species, the remaining FE were sterile. After reprocessing, all FEs were protein-free (< 1 μg). The artificially contaminated test bodies showed no remaining bacterial contamination after disinfection, resulting in an average absolute germ reduction of about 10⁷ CFU.

Conclusion

Impelux™ UV-C light technology efficiently reduces bacterial contamination of FEs and might be useful in daily practice.

Disposable versus Reusable Ureteroscopes: A Prospective Multicenter Randomized Comparison

Purpose

To compare reusable and disposable flexible ureteroscopes in terms of efficacy and safety for patients undergoing Retrograde Intrarenal Surgery (RIRS).

Patients and Methods

Patients with a renal stone eligible for RIRS were enrolled in this multicenter, randomized, clinical trial study. Patients were randomized into two groups: group A (90 patients) underwent RIRS with a reusable flexible ureteroscope and group B (90 patients) were treated with a disposable one.

Results

The patients’ demographics, stone features and pre-operative urine cultures were comparable between the groups. The Stone Free Rates (SFRs) were not significantly different (86.6% and 90.0% for group A and group B, respectively, p=0.11) and the mean cost for each procedure was comparable (2321 € in group A vs 2543 € in group B, p=0.09). However, the days of hospitalization and of antibiotic therapy were higher in group A (p ≤ 0.05). The overall complication rate in group A was 8.8% whilst in group B it was 3.3% (p ≤ 0.05); in particular, group A exhibited a greater number of major complications (Clavien score IIIa-V). The overall postoperative infection rate was 16.6% in group A and 3.3% in group B (p ≤ 0.05). Furthermore, none of the patients in group B developed urosepsis or had a positive blood culture, while 3 patients in group A did (p<0.05).

Conclusion

The use of disposable ureteroscopes is characterized by significantly lower post-operative complications and infection rates, while having comparable costs and SFRs vis à vis reusable ureteroscopes. Clinical Trial Registration Number: ISRCTN92289221.

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.

Non-tuberculous Mycobacterial Pseudo-outbreak of an Intestinal Culture Specimen Caused by a Water Tap in an Endoscopy Unit

Objective Gastrointestinal lesions of non-tuberculous mycobacteria (NTM) are regarded as opportunistic infections. A large number of positive specimens of NTM were identified in an intestinal fluid culture in the endoscopy unit and it was considered to be a pseudo-outbreak. Methods We reviewed the hospital, laboratory, and colonoscopy records of 263 consecutive patients whose intestinal fluids were analyzed for a mycobacterial culture by colonoscopy at St. Marianna University Hospital, between January 2009 and December 2018. The endoscopy reprocessing procedures were reviewed and samples of water used in the endoscopy unit were cultured. Results An intestinal fluid culture of 154 (58.6%) patients tested positive for NTM (M. intracellulare; 125 cases, M. gordonae; 14 cases, M. avium; 4 cases, M. abscessus; 3 cases, and 8 other cases). In 182 cases (69.2%), an intestinal mucosal culture was performed simultaneously with a fluid culture and tested positive for NTM in 2 cases. Next, we examined the endoscopy unit for any possible environmental contamination. NTM were detected in the tap water used to prepare the antifoaming solution in the endoscopy unit. The water faucets in the endoscopy unit were considered to be the source of the contamination of NTMs. Conclusion We observed that a large number of cases tested positive due to contaminated water that had been used in an endoscopy unit, thus leading to a pseudo-outbreak of NTM.

Research: Fluorescence Microscopy-Based Protocol for Detecting Residual Bacteria on Medical Devices

Standard methods are needed to reliably and efficiently assess bacterial contamination of processed medical devices. This article demonstrates a standard operating procedure (SOP) for fluorescence microscopy-based detection of residual bacteria on medical devices (BAC-VIS). BAC-VIS uses a 4',6-diamidino-2-phenylindole (DAPI) stain with fluorescent microscopy to quickly and cost-effectively detect bacterial contamination of processed medical device parts. The BAC-VIS protocol was optimized and achieved greater than 80% staining efficiency and a signal-to-noise ratio of more than 20 using four representative organisms. The SOP was first validated for use on a buildup biofilm model, accessory channels of contaminated clinically used devices, and inoculated endoscope end caps and O-rings. The buildup biofilm model was used to evaluate BAC-VIS after repeated treatment of adherent bacteria with three common high-level disinfectants: glutaraldehyde, ortho-phthalaldehyde, and peracetic acid. Next, BAC-VIS was used to assess clinically used endoscope parts that cultured positive for Gram-negative bacteria. DAPI-stained cells were found on all culture-positive devices, especially in grooves and imperfections on the surface. Finally, BAC-VIS was used to detect bacteria on inoculated endoscope device components. The results showed potential for BAC-VIS to be a valuable tool for industry and academic/medical researchers for investigations of contaminated medical devices. Results obtained using BAC-VIS can increase understanding of the role of design in cleanability, wear, and prevention of contamination and may lead to improvements in materials and design that could make processed endoscope use safer for patients. Of note, this protocol is not for detecting bacteria on scopes or scope parts that will be put back into clinical use.

Comparison of ureteric stent removal procedures using reusable and single-use flexible cystoscopes following ureteroscopy and lasertripsy: a micro cost analysis

Introduction

Diagnostic pressure on endoscopy suite can lead to delay in flexible cystoscopic stent removal. We compare the cost and organizational impact of reusable flexible cystoscope versus single-use, flexible cystoscope with a built-in stent grasper (Isiris^®).

Material and methods

Data for the reusable cystoscopic stent removal performed in endoscopy room, group A (period 1) were compared to Isiris disposable stent removal performed in outpatient clinic, group B (period 2). We chose the same calendar months in successive years for these two different groups (9 months each). A micro cost analysis was performed evaluating the impact on costs, complications and organizational benefit.

Results

A total of 72 patients (37, group A; 35, group B) were included with no significant differences in age and gender ratio. The mean procedure time was 14.4 and 2.2 minutes, and the mean stent dwell time was 26.8 and 15.4 days in groups A and B respectively (p <0.001). In group A, 5 patients (14%) developed stent encrustation, of which 3 needed a ureteroscopic removal subsequently. No complication occurred in group B. More staff on average were needed for procedures done in group A, than group B (p <0.001).

The number of patients who had cancer diagnostic wait of >2 weeks for flexible cystoscopy and the mean number of days they waited, reduced from 16 to 3, and 21 days to 3 days respectively between period 1 to period 2. The cost per procedure between group A and group B was £267.2 and £252.62 (p <0.05) if the cost of managing complications was not considered, and £365.40 and £252.62 (p <0.001) if the cost of managing complications was also considered.

Conclusions

Isiris significantly reduced stent dwell time, procedural time and staff needed to carry out the stent removals. It also allowed the procedures to be done in the outpatient setting thereby reducing the organizational pressure on endoscopy related diagnostic procedures.

[Cost minimization analysis of flexible ENT-endoscopes]

BACKGROUND

Reprocessing of complex instruments like flexible ENT-endoscopes with and without working channel are challanging for clinics and private practices. Aim of the study was to analyse the costs of an examination with a reusable endoscope-system and to compare it with two single-use endoscope-systems.

MATERIAL AND METHODS

A cost minimization analysis was performed at the Department of Otorhinolaryngology, Head and Neck Surgery of the University Medical Center in Mainz, Germany. The local reusable endoscopy-system was compared with two single-use endoscopy-systems of Ambu and Karl Storz.

RESULTS

Overall costs per examination with a reusable-scope were 23.03 € (11.60 € investment costs + 5.09 € repair costs + 6.34 € reprocessing costs). The single-use Endoscopy-system of Ambu resulted in 120.43 € per examination (120.00 € acquisition costs + 0.43 € storage costs). Overall costs for the single-use endoscopy-system of Karl Storz were 223.44 € per examination (investment costs for monitors 3.01 € + 220.00 € acquisition costs + 0.43 € storage costs).

DISCUSSION

Flexible single-use ENT-endoscopy-systems generate higher costs in comparison to conventional reusable ones. But there are also advantages from the medical and economical side.

CONCLUSION

A smart mix of reusable and single-use endoscopy systems seems therefore usefull.

UV light-based decontamination: an effective and fast way for disinfection of endoscopes in otorhinolaryngology?

Background

Reprocessing of endoscopes becomes increasingly complex, due to rising demands of hygiene. Established methods are often expensive/time-consuming. Recent studies suggest beneficial aspects of disinfection by UV light. In this study we analyzed the efficiency of UV light disinfection of rigid otorhinolaryngological endoscopes.

Materials and methods

After mechanical pre-cleaning, the endoscopes were decontaminated for 25 s in the D25 using Impelux™ UV C light technology (UV Smart B.V., Delft, The Netherlands). First, the surface contact samples were taken from 50 used endoscopes to evaluate the bacterial load. Additionally, surface contact samples were taken from further 50 used endoscopes after reprocessing with the D25. Another 50 endoscopes were tested on protein residuals. Furthermore, the absolute effectiveness of the D25 was tested on 50 test bodies (RAMS) with a standardized contamination of 10⁷ colony-forming units (CFU) of Enterococcus faecium.

Results

The used endoscopes showed a high bacterial contamination with an average value of 66.908 (± 239.215) CFU. After reprocessing, only a minimal contamination on 10% (n = 5) of the endoscopes with a mean value of 0.12 CFU (± 0.39) was found, resulting in a log-5 reduction in a clinical environment. The documented bacteria were components of the normal skin flora. All tested endoscopes were practically protein-free (< 1 μg). Furthermore, the average absolute germ reduction of the D25 was about 10⁶ CFU on the tested RAMS.

Conclusion

The D25 UV light system seems to be an effective device for the reprocessing of rigid ORL endoscopes, and therefore, might be suitable for the usage in clinical practice on site.

Contribution of usage to endoscope working channel damage and bacterial contamination

BACKGROUND

Biofilm formation has been shown to be associated with damaged areas of endoscope channels. It was hypothesized that the passage of instruments and brushes through endoscope channels during procedures and cleaning contributes to channel damage, bacterial attachment and biofilm formation.

AIM

To compare surface roughness and bacterial attachment in used and new endoscope channels in vivo and in vitro.

METHODS

Surface roughness of 10 clinically used (retired) and seven new colonoscope biopsy channels was analysed by a surface profiler. For the in-vitro study, a flexible endoscope biopsy forceps was passed repeatedly through a curved 3.0-mm-diameter Teflon tube 100, 200 and 500 times. Atomic force microscopy was used to determine the degree of inner surface damage. The number of Escherichia coli or Enterococcus faecium attached to the inner surface of the new Teflon tube and the tube with 500 forceps passes in 1 h at 37^oC was determined by culture.

RESULTS

The average surface roughness of the used biopsy channels was found to be 1.5 times greater than that of the new biopsy channels (P=0.03). Surface roughness of Teflon tubes with 100, 200 and 500 forceps passes was 1.05-, 1.12- and 3.2-fold (P=0.025) greater than the roughness of the new Teflon tubes, respectively. The number of E. coli and E. faecium attached to Teflon tubes with 500 forceps passes was 2.9-fold (P=0.021) and 4.3-fold (P=0.004) higher compared with the number of E. coli and E. faecium attached to the new Teflon tubes, respectively.

CONCLUSION

An association was found between endoscope usage with damage to the biopsy channel and increased bacterial attachment.

Enzymatic detergent reuse in gastroscope processing: a potential source of microorganism transmission

OBJECTIVE

to evaluate the potential contamination of enzymatic detergent from its reuse and to identify the microbiological profile in the solution used to clean gastrointestinal endoscopic devices.

METHOD

cross-sectional study based on microbiological analysis of 76 aliquots of 19 different enzymatic detergent solutions used to clean endoscopic devices. The aliquots were homogenized, subjected to Millipore® 0.45 µm membrane filtration and the presumptive identification of microorganisms was performed by biochemical-physiological methods according to previously established specific bacterial groups that are of clinical and epidemiological relevance.

RESULTS

the mean values, as well as the standard deviation and the median, of the enzymatic detergent microbial load increased as the solution was reused. There was a significant difference between the means of after first use and after fifth reuse. A total of 97 microorganisms were identified, with predominance of the coagulase-negative Staphylococcus, Pseudomonas spp., Klebsiella spp., Enterobacter spp. genus, and Escherichia coli species.

CONCLUSION

the reuse of the enzymatic detergent solution is a risk to the safe processing of endoscopic devices, evidenced by its contamination with pathogenic potential microorganisms, since the enzymatic detergent has no bactericidal property and can contribute as an important source for outbreaks in patients under such procedures.