Gastroenterology Today - Autumn 2019

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Endoscope reprocessing: we’re only human We’re only human was an American movie directed by James Flood and released in 1935. Even then, there was great interest in shifting from human work to automated assembly lines. But what does this have to do with the reprocessing of flexible endoscopes? In my opinion, it is related to today’s reprocessing problems of these complex medical devices. For decades we have known that flexible endoscopes – even when cleaned and disinfected can be a source of debris, biofilm and thus micro-organisms, leading to serious infection problems. Just take a look at the headlines about contaminated, so called ‘superbug’, endoscopes. However, manual reprocessing is still underestimated and reprocessing staff are only human.

The importance of endoscopy Since the introduction of the first flexible endoscope in 1956 by Basil Hirschowitz and Larry Curtis, the number of procedures using these devices has increased enormously. Only in the United States approximately 75 million procedures were performed in 2017 [, 28 may 2018]. And it is expected that this number will increase in the next decades. A procedure with a flexible endoscope has many advantages compared to traditional procedures and they are very safe. Of course, like any other procedure, there are also potential complications like perforation, bleeding, pancreatitis (as a result of ERCP) or infection. Focusing on the last one, these infections can originate from the patients own bacterial flora, or from exogenous flora, transmitted by a previously used endoscope.



Complex, reusable devices Flexible endoscopes are complex, reusable medical devices. During a procedure they can become highly contaminated with organic materials and bacteria. Studies have showed a high bacterial contamination inside the channels of sometimes more than 10^9 CFU per channel (one billion colony forming units) [Rutala WA, Weber DJ. Reprocessing endoscopes: United States perspective. J Hosp Infect. Apr 2004;56 Suppl 2: S27-31. Kaczmarek RG et al. Am J Med 1992;92:257-261]. Flexible endoscopes need to be thoroughly reprocessed between each patient, to guarantee a safe subsequent use. Simultaneously with the technical development, extensive use of endoscopes and identified outbreaks due to contaminated endoscopes, techniques for cleaning and disinfection were improved. One of the most important innovations in endoscopy was the introduction of high-level disinfection of endoscopes [Sivak MV. Gastrointestinal endoscopy: past and future. GUT. 2006, Aug; 55(8), 1061-1064). The role of automated endoscope-disinfectors With the introduction and increased usage of automated high-level endoscope-disinfectors, practitioners developed

an utopic belief that the problem of contaminated endoscopes would belong to the past. Now that the reprocessing process was automated, controlled, and could be retrieved and validated. Practitioners thought that manual cleaning was not necessary anymore with these endoscope-disinfectors - which also contained a cleaning and increased rinsing stage, with reduced human failures in reprocessing. However, reality was different: even with the use of these disinfectors, outbreaks due to contaminated endoscopes kept occurring. Endoscopes were still not clean enough after reprocessing [Kovaleva, 2013]. This is not a surprise. Underestimated manual cleaning With only flushing water with detergent to disinfectant through the channels, automated endoscope-disinfectors were not able to remove any debris, biofilm and thus micro-organisms. Although some endoscope-disinfectors claim a 90% reduction of debris in the first step inside cleaning [Alfa et al, 2006], the manual cleaning before automated cleaning and disinfection is still the most important step [Beilenhoff, ESGE-ESGENA 2018]. Manual brushing and flushing of the endoscope, using the right procedures and techniques, removes > 90% of all debris, biofilm and micro-organisms [Chu NS, McAlister D, Antonoplos PA. 1998. Natural bioburden levels detected on flexible gastrointestinal endoscopes after clinical use and manual cleaning. Gastrointest. Endosc. 48:137–142]. The last 10% can be removed by the automated endoscope-disinfector. However, in daily practice, the manual cleaning stage is downgraded to just a simple flush and brush, despite all reported outbreaks and the detailed IFUs for manual cleaning. The question is: why? Time pressure in reprocessing units Since the number of endoscopic procedures is increasing enormously, there is a great pressure on the availability of reprocessed endoscopes. With the high turnover of endoscopes, time has become the key factor in many endoscopy wards and reprocessing units. After use,