Setting
This study was performed at the department of Otorhinolaryngology and Head and Neck Surgery of the Radboud university medical center, a tertiary university hospital in The Netherlands. From January 2022 until May 2022, FEs without a working channel were examined. The FEs were used to examine the nasal cavity, pharynx or larynx of the entire spectrum of ORL patients(infectious and non-infectious patients). To evaluate the effectiveness of UV-C light disinfection, only contaminated FEs without a working channel(VNL9-CP, PENTAX Medical B.V., Dodewaard, The Netherlands) were used. FEs without a working channel that showed no contamination after clinical use and manual pre-cleaning were excluded, since assessing the disinfection process in these FEs was impossible.
The used FEs were randomly assigned to the UV-C light group (group 1) or the Endoscope Washer Disinfection group (group 2). In order to make the disinfection process, culture collection and assessment as standardized as possible, they were performed by two researchers(YH and MR). Before the start of the study, both researchers were trained in these tasks by a senior infection prevention specialist(SC).
As protocolled by the hospital, FEs without a working channel should receive a manual pre-cleaning using water and chemicals in order to remove visible dirt and debris. However, to best evaluate the disinfection process itself, in this study pre-cleaning was performed using only water. A gauze pad was moistened with tap water and moved several times in a rotary motion from proximal to distal across the FE to remove visible debris. A culture was then taken from the FE(culture 1). Next, the FE was placed and disinfected for 60 seconds in the D60 UV-C light disinfector(group 1), or for 22 minutes in the EWD(group 2). After disinfection, a new culture was taken(culture 2). To not interfere with current patient safety regulations, all FEs were finally reprocessed by the EWD, as protocolled by our hospital. Due to mandatory changes in reprocessing logistics during our study, some FEs in group 2 were reprocessed in a central processing department and received additional manual pre-cleaning with Neodisher® MediClean forte(Dr. Weigert Nederland B.V., Assen, The Netherlands).