Comparison of automated and manual drying in the elimination of residual endoscope working channel fluid after reprocessing (with video)

Abstract

Background and aims: Residual fluid within endoscope working channels after reprocessing may promote growth of pathogens. Current reprocessing guidelines therefore recommend endoscope drying with administration of forced filtered air; however, the duration and modality of administered air are not specified. The new DriScope Aid device enables automated administration of filtered air at controlled pressure through all internal endoscope channels. We systematically compared, for the first time, the impact of manual drying and automated drying on retained working channel fluid and bioburden after reprocessing.

Methods: We assessed for residual working channel fluid after reprocessing and/or drying by using the SteriCam borescope. Drying was performed either manually (forced filtered air) or was automated (DriScope Aid) for either 5 or 10 minutes. Adenosine triphosphate (ATP) bioluminescence testing was performed on working channel rinsates after drying, to evaluate for residual bioburden.

Results: Significantly more fluid droplets were evident after manual drying (4.55 ± 6.14) than with automated device-facilitated drying for either 5 minutes (0.83 ± 1.29; P = .007) or 10 minutes (0 ± 0; P = .001). ATP bioluminescence values were higher for manual drying compared with automated drying at 48 hours (P = .001) and 72 hours (P = .014) after reprocessing.

Conclusions: We demonstrate significantly fewer water droplets and delayed ATP bioluminescence values within endoscope working channels after automated drying compared with manual drying. In particular, virtually no retained fluid was evident within endoscope working channels after automated drying for 10 minutes. These findings support recommendations for automation of as many reprocessing steps as possible. Automated drying may decrease the risk of transmission of infection related to endoscopy.

Figure 1.

Study flow diagram: Working channel visual inspections and rinsate collections were performed at baseline (within 30 minutes) and at 24, 48, and 72 hours after endoscope reprocessing and/or drying. ATP, Adenosine triphosphate bioluminescence.

Figure 2.

A, Image of the DriScope Aid device. B, Disposable tubing and/or connectors.

Figure 3.

A, Qualitative visual assessment of fluid expelled from the endoscope tip when the DriScope Aid device was connected for an additional 5 minutes of drying after manual drying. B, Qualitative visual assessment of fluid expelled from the endoscope tip when the DriScope Aid device was connected for an additional 5 minutes of drying after 5 minutes of automated drying was performed. The scale bar on each image represents 1 cm.

Figure 4.

A, Borescope examination demonstrating a coalescing pool of fluid (long arrows) and individual fluid droplets (short arrows) after high-level disinfection and 1-minute air purge in the automated endoscope reprocessor. B, Discrete fluid droplets after high-level disinfection, 1-minute air purge in the automated endoscope reprocessor, and 10 minutes of manual drying. C, Rare, discrete fluid droplet (arrow) after high-level disinfection, 1-minute air purge in the automated endoscope reprocessor and 5 minutes of automated drying.