Infection Control Today

JUN 2019

ICT delivers to infection preventionists & their colleagues in the operating room, sterile processing/central sterile, environmental services & materials management, timely & relevant news, trends & information impacting the profession & the industry

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25 June 2019 ICT The rates of endoscope contamination may even be much higher. It's difficult to detect potential pathogens quickly and completely because of inadequate surveillance methods and long lag times between contamination and infection. Generally, recognition of contamination takes place after the appearance of unusual pathogens, as was the case with New Delhi metallo-beta-lactamase (NDM)-producing E. coli. The risk level also varies by procedure, with some, such as colonoscopy, much more prone to colonization than others. The condition of the patient is another factor – whether they are older, immunocompromised, have cancer or other ailments. Repeated outbreaks have been blamed on inadequate cleaning and inappropriate disinfection (e.g., failure to perfuse all channels), damaged endoscopes or faws in the design (for example, with the duodenoscope elevator channel), and issues with automated endoscope reprocessors (AERs). The complexity of endoscopes, with their unwieldy, long, narrow channels, right-angle turns, and small crevices make them extremely diffcult to clean. In addition, microorganisms often reside in scratches, grooves, and irregular surfaces that invariably occur on endoscopes subject to regular use. If endoscopes are not completely dried after cleaning, any remaining viable microbes can rapidly proliferate and colonize the instrument. The age of the endoscope and improper storage have also been found to contribute to higher contamination rates. "To mitigate the risk of exposure, most endoscopy centers have implemented enhanced reprocessing techniques, such as repeated high-level disinfection," according to Rutala. However, studies have shown that this procedure does not reduce the level of contamination of the devices. One problem is that the brushes, detergents, and disinfectants do not always get to hard-to-reach areas exposed to contaminants, even with a second cleaning. In addition, researchers have found that healthcare workers often don't follow proper cleaning procedures. In addition, all the steps needed for proper manual endoscope reprocessing are rarely performed and some essential steps – for instance, brushing all endoscope channels and components – are often skipped. Many healthcare facilities have a small inventory of endoscopes and want to get them turned around for reuse quickly, often at the expense of cleanliness and patient safety. Using AERs has contributed somewhat to improved reprocessing because most steps are automated and standardized, but even this is not suffcient. While improvements to cleaning and monitoring guidelines and the design are important, the problem of contamination will not be solved unless we revise the way that endoscopes are classifed in the Spaulding scheme. Developed in 1968 by Dr. Earle Spaulding, this classifcation scheme defned how an object should be disinfected based on its intended use. According to Dr. Spaulding's protocol, instruments defned as "semi-critical" are any devices that contact intact mucous membranes. The recommended reprocessing guideline for semi-critical objects is cleaning followed by high-level disinfection (HLD). Items defned as "critical" are those that enter sterile tissue or the vascular system or through which blood fows, and require cleaning followed by sterilization. It should also be noted that many of the tools which are used in these endoscopes have been deemed as critical in the Spaulding classifcation. This lack of uniformity between scope and tool creates a problem, as the critical tool will become contaminated as it passes through a dirty channel. Now that we have a clearer picture of the challenges and risks associated with endoscope reprocessing, we know that the only way to prevent further contamination is to clarify the Spaulding classifcation. Rutala has recom- mended that complex devices that directly or indirectly enter normal sterile tissue or the vascular system, such as bronchoscopes, cystoscopes, or duodenoscopes, need to be defned as critical and should require sterilization. This would mean that colonoscopes that have contact with non-intact mucous membranes would be defned as a critical item requiring sterilization. The same would apply to the duodenoscope, cystoscope, and bronchoscope, as they indirectly contact a normally sterile tissue such as bile ducts, bladder and lungs. Evidence shows that HLD of endoscopes provides little to no margin of safety, while sterilization has been proven to signifcantly reduce microbial contamination. Rutala notes that the "FDA mandated a similar shift from disinfection to sterilization for dental hand pieces in 1992 … even though there were no documented cases of disease transmission associated with these instruments." By contrast, the infection data for endoscopes is overwhelming and irrefutable. In May 2015, an FDA panel recommended the sterilization of duodenoscopes. But reprocessing guidelines have not yet changed. To ensure patient safety, it is critical that we move from high-level disinfection to sterilization of all endoscopes. For this to happen, Rutala has recommended that professional and consensus standard organizations such as SHEA, APIC, SGNA, ASGE, and AAMI, as well as device manufacturers, regulatory agencies, doctors, and inpatient and outpatient endoscope reprocessing centers, all need to facilitate these changes through guidelines, research, and education. New technologies are now being developed that will help: New or optimized low-temperature sterilization technologies, disposable sterile endoscopes, steam sterilization for GI endoscopes, and the growing use of non-endoscopic diagnostic methods, such as capsular endoscopy, or "liquid" biopsies to detect cancer. Adopting these technologies as soon they are approved will add to our efforts for change. Working together on all these fronts, we can signifcantly reduce this serious, if still under-recognized, problem. Stephen Spanos, MD, is medical director at Ambu, which manufactures and sells medical products including bronchoscopes, resuscitators and electrodes, and is credited with developing the world's frst single-use fexible endoscope. Spanos is chairman of regional anesthesia at Primary Children's Hospital and assistant professor in the department of anesthesiology at the University of Utah. Ò To mitigate the risk of exposure, most endoscopy centers have implemented enhanced reprocessing techniques , such as repeated high-level disinfection.

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