Automatic washer disinfector for flexible endoscopes: a new evaluation process

Endoscopy. 1997 Jun;29(5):372-9. doi: 10.1055/s-2007-1004218.

Abstract

Background and study aims: Many automatic washer disinfectors for flexible endoscopes have been marketed and offered as an alternative method of preventing infections, but they are frequently unsatisfactory. There is therefore clearly a need to test prototypes prior to marketing, following an evaluation process that is sufficiently reliable and rigorous to guarantee the efficacy of the decontamination processes.

Materials and methods: The present study describes an experimental method based on the follow-up of the decontamination of a Tygon tube, the internal surface of which was contaminated by a bacterial biofilm. This method is proposed as a preliminary test for evaluating washer disinfectors.

Results: An analysis of the results obtained after technical modifications of the first prototype of the Fibro-Cleaner showed that complementary activities of each successive cycle phase allow a reduction in the number of adherent bacteria of more than 8 log per cm2 of support. With the three different biofilms tested (Escherichia coli, Pseudomonas aeruginosa mucoid and Staphylococcus aureus), no microorganisms were recovered from the support at the end of the decontamination process.

Conclusions: The experimental protocol suggested here seems to be well suited for assessing washer disinfectors during the development phase of the prototype, as well as for comparative studies.

MeSH terms

  • Biofilms
  • Disinfection / methods*
  • Endoscopes*
  • Equipment Contamination / prevention & control*
  • Escherichia coli / isolation & purification
  • Evaluation Studies as Topic
  • Pseudomonas aeruginosa / isolation & purification
  • Staphylococcus aureus / isolation & purification