Instruments

Zühlsdorf B, Kampf G, Floss H, Martiny H.
Suitability of the German test method for cleaning efficacy in washer-disinfectors for flexible endoscopes according to prEN ISO 15883.
J Hosp Infect. 2005; 61 (1):46-52.

Content
In Europe, reprocessing processes of flexible endoscopes in washer disinfectors (WD) are evaluated in compliance with prEN ISO 15883-1, which includes a determination of the efficacy of the cleaning process. For separate determination of the cleaning process, the German test method as part of prEN ISO 15883-1 (annex B) is applied. Recent investigations using the German test method resulted in major differences in the efficacy of individual cleaning processes. In order to assess the validity of the German test method, the study carried out a total of 72 experiments. 7 cleaning agents were used according to the manufacturers' instructions in 21 cleaning processes. In addition, three cleaning processes were carried out with water only. Every cleaning process was executed triply and evaluated by determining the average value of all three experiments. The study comes to the conclusion that the German prEN ISO 15883-1 test method is suitable for evaluating cleaning processes in WDs and leads to reproducible, valid results.

Zühlsdorf B, Floss H, Martiny H.
Efficacy of 10 different cleaning processes in a washer disinfector for flexible endoscopes.
J Hosp Infect. 2004; 56: 305-311.

Content
Successful cleaning of medical devices, such as flexible endoscopes, has been recognized to be of major importance for effective reprocessing. Washer disinfectors (WD) are considered to be an important step in this direction. However, the cleaning process in WDs has only been partially assessed in terms of efficacy. In order to study this in more detail, tests which used transparent Teflon tubes as test pieces (2 m length) were carried out in accordance with prEN ISO 15883.

A German-language reprint of this study can be requested at
Dagmar Martini

Pajkos A, Vickery K, Cossart C.
Is biofilm accumulation on endoscope tubing a contributor to the failure of cleaning and decontamination?
J Hosp Infect. 2004; 58:224–229.

Content
Biofilms are difficult to remove with the currently available cleaning procedures. It was tested whether biofilms develop on surfaces of endoscope tubing having been in contact with fluids.

A German-language reprint of this study can be requested at
Dagmar Martini

Kampf G, Bloß R, Martiny H.
Surface fixation of dried blood by glutaraldehyde and peracetic acid.
J Hosp Infect. 2004; 57: 139-143.

Content
The difficulties of successful prion inactivation by chemical disinfectants have led to new requirements on the reprocessing of instruments, including flexible endoscopes. One demand is the preference for peracetic acid instead of glutaraldehyde in order to avoid fixation of organic material. In this study, the fixation properties of various chemical disinfectants have been investigated. It has been shown that not only glutaraldehyde leads to blood fixation, but also peracetic acid. The result once again underlines the importance of a thorough cleaning prior to the execution of the chemical disinfection.