Elution of working channels with the flush-brush-flush method for evaluation of the cleaning efficacy of endoscopes

M Wehrl, P Barone, FHH Brill, M Dabrowski, M Decius, D Diedrich, L Feiler, J Gebel, D Geyer, A Halvarsson, N Herget, J Hoffmann, B Hücker, A Kampe, B Kampf, J Lenz, H Martiny, U Orschel, M Plevschinski, M Rausch, O Riebe, K Roth, J Scharte, L Schnieder, N Schröder, T Schwemmer-Cordes, K Seekamp-Schnieder, T Seis, C Uhlig

Zentralsterilization | Volume 33 - 6/2025 | Dezember 2025 | mhp Verlag

Part 1: Description of the method and quantitative residual protein measurement results from Field Study 2

Abstract: Based on the flush-brush-flush (FBF) method, a method for assessing the cleaning effect (product control) in the brush-accessible working channel of thermolabile endoscopes was developed. The development work was carried out by Methods Group 2.0 on behalf of the guideline groups. After several comparative studies using well standardised process challenge devices, the new method was evaluated in n = 28 medical facilities to characterise the recovery effect in the working channel of n = 80 endoscopes after use on patients having undergone pre-cleaning, manual cleaning and, if applied, subsequent automated cleaning and intermediate rinsing. The study was conducted in a consistent manner, so that the cleaning effect was examined on each instrument by means of simple rinsing (1st flush, F method) and additionally by brushing and 2nd rinsing (brush, 2nd flush, FBF method). The results demonstrate that when using the FBF method, higher residual protein levels could be determined in a higher percentage of endoscopes compared to the F method. Consequently, the new sampling method shows increased sensitivity.