Microbiological monitoring of flexible bronchoscopes after high-level disinfection and flushing channels with alcohol: Results and costs - 30/07/15

Routine microbiological surveillance of flexible bronchoscopes is recommended in different guidelines. The study aims to assess whether bronchoscopes reprocessing methods achieved an appropriate decontamination level and whether manual flushing of 70% ethyl alcohol at the end of the cycle reduces the risk of microbiological contamination.

18 different bronchoscopes were cultured on a monthly basis during a four-year period to examine growing of bacteria, fungi and mycobacteria. 9 equipment were usually disinfected using automatic reprocessors, and the other 9 equipments were manually disinfected. Additional manual flushing of bronchoscope's channels with 70% ethyl alcohol at the end of each disinfection cycle, was implemented for automatically reprocessed equipments for a two-year period.

A total of 620 samples were obtained. 564 samples (91.0%) tested negative and 56 samples (9%) tested positive for at least one specimen, of whom 3% were pathogenic or potentially pathogenic microorganisms. Only one positive sample was detected among the 167 alcohol treated bronchoscopes (0.6%), whereas before the introduction of this technique the percentage of contamination with risk pathogens was 4.1% (p = 0.04). The mean annual cost of the surveillance program was estimated at 23,035 euros, and the mean cost for bronchoscope was 111.5 euros.

The results of our study support to improve the final reprocessing of bronchoscope channels by means of additional manual flushing with 70% ethyl alcohol after each disinfection cycle. Routine microbiologic monitoring of endoscopes is both time-consuming and expensive but could be saved by implementing a highly efficient decontaminating procedure.