Currently, flexible endoscopes, including gastrointestinal,
urological, and respiratory endoscopes, are reused following cleaning
and high-level disinfection.
Current techniques used to clean endoscopes for reuse are not consistently effective, revealed a study published in the February issue of the American Journal of Infection Control, the official journal of the Association for Professionals in Infection Control and Epidemiology.
‘Even though top-notch reprocessing techniques were used, the endoscopes in this study had visible signs of damage and debris, and tests showed a high proportion were still contaminated.’
The findings of this study support the need for careful visual
inspection and cleaning verification tests to ensure that all endoscopes
are free of damage and debris before they are high-level disinfected or
sterilized and used on another patient.
“APIC is concerned about the risk of infections related to
endoscopic procedures,” said Linda Greene, 2017
APIC president. “This study reinforces the importance of having strong
infection prevention and control programs at all types of facilities,
led by highly trained infection preventionists, to ensure that
facilities are following the latest evidenced-based guidance.”
Results from the new study
conducted by Ofstead & Associates, Inc., suggest that even more
rigorous reprocessing techniques of endoscopes are not consistently
effective, and organic residues often remain.
“Understanding issues with the effectiveness of reprocessing
techniques is critically important as institutions seek to improve the
quality of endoscope cleaning and disinfection,” said lead study author
Cori L. Ofstead, Ofstead & Associates, Inc. “Even though
top-notch methods were used, the endoscopes in this study had visible
signs of damage and debris, and tests showed a high proportion were
Using a longitudinal study design, Ofstead, et al. performed three
assessments of 20 endoscopes over a seven-month period. The assessments
involved visual inspections with a tiny camera, microbial cultures, and
biochemical tests to detect protein and adenosine triphosphate (ATP) – a
marker that identifies organic matter. These assessments were used to
identify endoscopes that required further cleaning and maintenance.
During the final assessment, the researchers found that all 20
endoscopes examined had visual irregularities, such as fluid,
discoloration, and debris in channels. Furthermore, samples from 12 of
20 reprocessed endoscopes (60%) had microbial growth, indicating a
failure of the disinfection process. Of note, endoscopes reprocessed
using current recommended guidelines and those that were cleaned at
least twice before high-level disinfection exhibited similar culture
Further results indicated that about 20% of endoscopes in
each group exceeded post-cleaning benchmarks for ATP and protein
residue. Moreover, ATP levels were higher for gastroscopes, which are
used for upper GI procedures, than the endoscopes used for colonoscopy.
“Since the same technicians used the same techniques to clean and
disinfect these scopes, the findings and our visual observations suggest
that something is happening to gastroscopes during procedures that
changes the surfaces and causes reprocessing failures,” says Ofstead.
This study comes on the heels of a 2015 report of
Carbapenem-resistant Enterobacteriaceae (CRE) infections related to
Endoscopic Retrograde Cholangio-Pancreatography (ERCP)
duodenoscopes – devices that are threaded through the mouth, throat, and
stomach into the top of the small intestine (duodenum) for examinations
and treatment. No breaches in reprocessing were identified and yet
infections related to the duodenoscopes were uncovered, raising concerns
that current reprocessing techniques were ineffective, and illuminating
the challenges in reprocessing of such intricate medical devices.
“The finding of residual fluid in 95% of endoscopes tested
was significant because moisture fosters microbial growth and the
development of biofilm – which can be difficult or impossible to remove,”
said Ofstead. “This confirms the importance of cleaning, disinfecting,
and drying to ensure patient safety.”