Reprocessing Flexible Endoscopes
Objectives
Risks associated with reprocessing flexible endoscopes
Causes of contamination and infection
Gaps in current reprocessing standards
Establish scientific rationale and evidence requirements for
enhancing safe practices
3. Reprocessing Flexible Endoscopes
Objectives
Risks associated with reprocessing flexible endoscopes
Causes of contamination and infection
Gaps in current reprocessing standards
Establish scientific rationale and evidence requirements for
enhancing safe practices
5. ENDOSCOPES
Widely used diagnostic and therapeutic procedure
GI endoscope contamination during use
Semicritical items require high-level disinfection
minimally
Inappropriate cleaning and disinfection has lead to
cross-transmission
In the inanimate environment, although the
incidence remains very low, endoscopes represent
a significant risk of disease transmission
6.
7. Disinfection and Sterilization
EH Spaulding believed that how an object will be
disinfected depended on the object’s intended use.
CRITICAL - objects which enter normally sterile
tissue or the vascular system or through which
blood flows should be sterile.
SEMICRITICAL - objects that touch mucous
membranes or skin that is not intact require a
disinfection process (high-level disinfection [HLD])
that kills all microorganisms but high numbers of
bacterial spores.
NONCRITICAL -objects that touch only intact skin
require low-level disinfection .
8. Multi-Society Guideline for Reprocessing
Flexible Gastrointestinal Endoscopes, 2011
Transmission categorized as:
Non-endoscopic and related to care of
intravenous lines and administration of
anesthesia or other medications
Multidose vials
Reuse of needles and syringes
Intravenous sedation tubing
Endoscopic and related to endoscope and
accessories
Failure to sterilize biopsy forceps between patients
Lapses in reprocessing tubing used in channel irrigation
9. Nosocomial Infections via GI
Endoscopes
Infections traced to deficient
practices
Inadequate cleaning (clean all channels)
Inappropriate/ineffective disinfection (time exposure, perfuse
channels, test concentration, ineffective disinfectant, inappropriate
disinfectant)
Failure to follow recommended disinfection practices (tapwater
rinse)
Flaws and complexity in design of endoscopes or AERs
10. DECREASING ORDER OF RESISTANCE OF
MICROORGANISMS TO
DISINFECTANTS/STERILANTS
Prions
Spores (C. difficile)
Mycobacteria
Non-Enveloped Viruses (norovirus, polio, HPV,
parvo)
Fungi
Bacteria (MRSA, VRE,
Acinetobacter)
Enveloped Viruses
Most Susceptible
Most Resistant
11. C. difficile:
MICROBIOLOGY AND EPIDEMIOLOGY
Gram-positive bacillus: Strict anaerobe, spore-former
Colonizes human GI tract..
Increasing prevalence and incidence
New epidemic strain that hyper-produces toxins A and B
Causes virtually all cases of antibiotic-associated
pseudomembranous colitis.
Introduction of CDI from the community into hospitals
High morbidity and mortality in elderly
Inability to effectively treat fulminant CDI
Absence of a treatment that will prevent recurrence of CDI
13. BIOFILMS
Bacteria residing within biofilms are many times
more resistant to chemical inactivation than
bacteria is suspension..
Does formation of biofilms within endoscopic
channels contribute to failure of decontamination
process.. Not known
Could be a reason for failure of adequate HLD
processes but if reprocessing performed promptly
after use and endoscope dry the opportunity for
biofilm formation is minimal
14. Transmission of Infection by
Endoscopy
Kovaleva et al. Clin Microbiol Rev 2013. 26:231-254
Scope Outbreaks Micro (primary)
Pts
Contaminated
Pts Infected
Cause
(primary)
Upper GI 19
Pa, H. pylori,
Salmonella
169 56
Cleaning/Dis-
infection
(C/D)
Sigmoid/Colo
noscopy
5
Salmonella,
HCV
14 6
Cleaning/Dis-
infection
ERCP 23 Pa 152 89
C/D, water
bottle, AER
Bronchoscopy 51
Pa, Mtb,
Mycobacteria
778 98
C/D, AER,
water
Totals 98 1113 249
Based on outbreak data, if eliminated deficiencies associated with cleaning, disinfection,
AER , contaminated water and drying would eliminate about 85% of the outbreaks.
https://journals.asm.org/doi/10.1128/CMR.00085-12?cookieSet=1
17. Audit Manual Cleaning of
Endoscopes
Issues for consideration
What is the clinical importance of <6.4µg/cm² for protein and <4
log₁₀ CFU/cm² bioburden: that is, has it been related
epidemiologically or clinically to decrease or increase risk of
infection?
ATP may be related to markers (e.g., protein) but markers may
have no relationship to microbes/disease and providing patient
safe instrument.
Ideally, validation of benchmarks should include correlation with
patients’ clinical outcome. The CDC has suggested that sampling
be done when there are epidemiological data that demonstrate
risk (e.g., endotoxin testing and microbial testing of water used in
dialysis correlated to increased risk of pyrogenic reactions in
18. Endoscope Reprocessing:
Current Status of Cleaning and Disinfection
Guidelines
Multi-Society Guideline, 12 professional
organizations, 2011
Centers for Disease Control and
Prevention, 2008
Society of Gastroenterology Nurses and
Associates, 2010
AAMI Technical Information Report,
Endoscope Reprocessing, In preparation
Food and Drug Administration, 2009
Endoscope Reprocessing, Health Canada,
2010
Association for Professional in Infection
Control and Epidemiology, 2000
19. FEATURES OF ENDOSCOPES THAT
PREDISPOSE TO DISINFECTION FAILURES
Require low
temperature disinfection
Long narrow lumens
Right angle turns
Blind lumens
May be heavily
contaminated with
pathogens, 10⁹
Cleaning (4-6 log₁₀
reduction) and HLD (4-6
log₁₀ reduction)
essential for patient
safe instrument
20. Endoscope Cleaning
Endoscope must be cleaned using water with detergents or
enzymatic cleaners before processing.
Cleaning reduces the bioburden and removes foreign material
(organic residue and inorganic salts) that interferes with the
HLD or sterilization process.
Cleaning and decontamination should be done as soon as
possible after the items have been used as soiled materials
become dried onto the endoscopes.
21. ENDOSCOPE REPROCESSING
Multi-Society Guideline on Endoscope
Reprocessing, 2011
PRECLEAN-point-of-use (bedside) remove debris by
wiping exterior and aspiration of detergent through
air/water and biopsy channels; leak test
CLEAN-mechanically cleaned with water and enzymatic
cleaner
HLD/STERILIZE-immerse scope and perfuse
HLD/sterilant through all channels for exposure time
(>2% glut at 20m at 20ᵒC). If AER used, review model-
specific reprocessing protocols from both the
endoscope and AER manufacturer
RINSE-scope and channels rinsed with sterile water,
filtered water, or tap water. Flush channels with alcohol
and dry
DRY-use forced air to dry insertion tube and channels
STORE-hang in vertical position to facilitate drying;
stored in a manner to protect from contamination
23. Automated Endoscope Reprocessors
Gastro Endoscopy 2010;72:675
All AERs have disinfection and rinsing cycles; some detergent
cleaning; alcohol flush and/or forced-air drying
Additional features may include: variable cycle times; printed
documentation; HLD vapor recovery systems; heating;
automated leak testing; automated detection of channel
obstruction, MEC
Not all AERs compatible with all HLDs or endoscopes; some
models designed with specific HLDs
Some AERs consume and dispose of HLD and other reuse HLD
Some AERs have an FDA-cleared cleaning claim (eliminates soil
and microbes equivalent to optimal manual cleaning-
<6.4µg/cm² protein)
24. Automated Endoscope Reprocessors (AER)
Manual cleaning of endoscopes is prone to error. AERs can
enhance efficiency and reliability of HLD by replacing some
manual reprocessing steps
AER Advantages: automate and standardize reprocessing steps,
reduce personnel exposure to chemicals, filtered tap water,
reduce likelihood that essential steps will be skipped
AER Disadvantages: failure of AERs linked to outbreaks, may
not eliminate precleaning BMC Infect Dis 2010;10:200
Problems: incompatible AER (side-viewing duodenoscope);
biofilm buildup; contaminated AER; inadequate channel
connectors; used wrong set-up or connector MMWR
1999;48:557
Must ensure exposure of internal surfaces with HLD/sterilant
25. Automated Endoscope Reprocessors
with Cleaning Claim
(requires procedure room pre-cleaning)
Medivator Advantage Plus
Endoscope Reprocessing System
Evo-Tech (eliminates soil and
microbes equivalent to optimal
manual cleaning. BMC ID
2010;10:200)
28. ResertTM HLD
High Level Disinfectant - Chemosterilant
2% hydrogen peroxide, in formulation
pH stabilizers
Chelating agents
Corrosion inhibitors
Efficacy (claims need verification)
Sporicidal, virucidal, bactericidal, tuberculocidal, fungicidal
HLD: 8 mins at 20ᵒC
Odorless, non-staining, ready-to-use
No special shipping or venting requirements
Manual or automated applications
12-month shelf life, 21 days reuse
Material compatibility/organic material resistance (Fe,
Cu)?
*The Accelerated Hydrogen Peroxide technology and logo are the property
of Virox Technologies, Inc. Modified from G MacDonald. AJIC 2006;34:571
29. Endoscopes: Delayed Reprocessing
and Drying
Delayed Reprocessing (GI Endoscopy 2011;73;853)
Reprocess immediately after use; do not allow to sit idle and soiled
for hours before being processed. If precleaning not initiated within
an hour, soak in detergent before cleaning.
Endoscope Drying (J Hosp Infect 2008;68:59)
Microbial contamination lower when stored in drying and storage
cabinet.
30. Endoscopes Reprocessed If Unused 5
Days
AORN, 2010
Investigat
or
Shelf
Life
Contaminatio
n Rate
Recommenda
tion
Osborne,
Endosco
py 2007
18.8h
medi
an
15.5% CONS,
Micrococcus,
Bacillus
Environmental
/process
contamination
Rejchrt,
Gastro
Endosc
2004
5
days
3.0% (4/135),
skin bacteria
(CONS,
diphteroids)
Reprocessing
before use
not necessary
Vergis,
Endosco
py 2007
7
days
8.6% (6/70),
all CONS
Reprocessing
not necessary
for at least
7d
Riley, GI
Nursing,
2002
24,1
68h
50% (5/10),
<3 CFU
CONS, S.
aureus, P.
Left for up to
1 week
Provided all channels thoroughly reprocessed and dried, reuse within 10-
14 appears safe. Data are insufficient to offer maximum duration for use.
31. IS THERE A STANDARD TO DEFINE
WHEN A DEVICE IS CLEAN?
There is currently no standard to define
when a device is “clean”, cleanliness
controlled by visual
Potential methods: level of detectable
bacteria; protein (6µg/cm²); endotoxin; ATP;
lipid
This is due in part to the fact that no
universally accepted test soils to evaluate
cleaning efficiency and no standard
procedure for measuring cleaning efficiency
32. Conclusions
Endoscopes represent a nosocomial hazard. Narrow margin of
safety associated with high-level disinfection of semicritical
items. Guidelines must be strictly followed.
AERs can enhance efficiency and reliability of HLD of
endoscopes by replacing some manual reprocessing steps
and reducing the likelihood that essential steps are not
skipped
Urgent need to better understand the gaps in endoscope
reprocessing-CRE, C. difficile spores, HPV, biofilms, etc.
Industry must support research to answer questions.
Data are insufficient to recommend ATP monitoring
Data suggest that contamination during storage for 7-14 days
is negligible.
35. Audit Manual Cleaning of
Endoscopes
Establishing Benchmarks
Lack of consensus regarding the clinical value of routine
microbiological monitoring of endoscopes. We perform to
assess the efficacy of reprocessing.
Alfa et al. Am J Infect Control 2012;40:233. Recommends
a bioburden residual of <100 CFU/ml.
Beilenhoff et al. Endoscopy; 2007;39: 175. ESGE-ESGENA
allows bioburden count of <20 CFU/ channel.
Heeg et al. J Hosp Infect; 2004;56:23. Contamination
should not exceed 1 CFU/ml. Certain organisms should
not be detected in any amount (e.g., P. aeruginosa, E.
coli, S. aureus)