Endoscope reprocessing: How to perform an adequate air drying?

Due to their transmission route, endoscopy-associated infections can be divided into endogenous and exogenous infections.

Endogenous infections are triggered by the spread of the patient's own local flora and mainly include Escheria coli, Klebsiella species, Enterobacter species and enterococci. Endogenous infections cannot completely be avoided due to the nature of endoscopic procedures and vary according to the invasiveness of the procedure.

Since the 1970 s there have been sporadic reports of exogenous infections associated with endoscopic procedures [1]. Since the 2000 s, increased focus has been given on exogenous infections with multi-resistant organisms [2]. In exogenous infections, the endoscope or the endoscopic instruments can be the vehicles for pathogenic or facultative pathogenic germs that originally come from previously examined patients or from the environment.

The decisive factor in triggering an exogenous infection is the germ load within the endoscope channels or on critical endoscope components (e. g. the albarran elevator).

The quality of endoscope reprocessing is an important factor in the development of exogenous infections:

• If cleaning and disinfection is insufficient, organic residues and germs remain on endoscope surfaces and in endoscope channels. If the endoscope is not dried sufficiently, these germs have enough moisture and good living conditions to multiply and become a danger to the next patient.

• If the last rinsing water contains germs, the freshly disinfected endoscope can be re-contaminated with this water. If the endoscope is not dried sufficiently, these germs can then multiply and pose a danger to the next patient.

Therefore, inadequate drying is not the sole cause of exogenous infections. It is rather a catalyst that amplifies existing errors and irregularities and turns them into a problem [3].

There are various manual and automated options available for drying and storage of flexible endoscopes. Kwakman et al. investigated a new device which provides an automated drying cycle and storage in a closed system.

Publication History

Article published online:
28 April 2023

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