Invasive Endoscopy –Technical Aspects
of Instruments, Reprocessing
Equipment and Sterile Supply
WFHSS 2016
17th World Sterilization Congress
Brisbane, 26 – 29 October 2016
T. Miorini Institute for Applied Hygiene / ÖGSV
The Problem
Processing◦ Thermolabile instruments
◦ Stressed by use and
processing
◦ High bioburden
◦ Long, narrow lumina and
hardly accessible parts
◦ Poor possibilities for visual
control of cleanliness
Practice
◦ As many examinations as
possible
◦ In as less time as possible
◦ With as few instruments
as possible
Obstacles for Reprocessing
High mechanical stress by use and
reprocessing
Limited durability against physical
and chemical impacts
Construction of an Endoscope
Air/Water Channel
Biopsy Channel
Suction Channel
Jet-Channel
Biofilm in Channels
20µm
With friendly permission of Dr. Lionel Pineau
Bioburden of flexible Endoscopes
After use:
Up to 1010 cfu /channel
Acceptance criteria
after processing:
< 10 cfu / channel
RF > 9 log (full cycle)
Case Reports
◦ HBV-Transmission
Birnie G.G. et al; Gut, Feb; 24(2):171-4
◦ HCV-Transmission after ERCP
Tennenbaum et al.; Gastroenterol Clin Biol 1993; 17(10):763-4
◦ Salmonella Newport InfectionTransmission by
Fiberoptic Colonoscopy
Dwyer et al. Gastrointest. Endosc. 1987
◦ Multidrug-resistant Klebsiella pneumoniaoutbreak after ERCP
Aumeran C. et al.; Endoscopy 2010 Nov;42(11); 895-9
WANTED!
Safe, effective and reproducible cleaning and disinfection
processes in washer-disinfectors
for flexible endoscopes
EN ISO 15883: Washer Disinfectors
Part 1: General Requirements, Definitions
and Tests
Part 4: Requirements and Tests for WDs for
flexible Endoscopes
Part 5: ISO/TS 15883-5 Test Soils and
Methods (in Revision)
Questions
Do all endoscope WDs which are on the market
comply with the requirements of the standard
ISO 15883?
Is the chemistry used in these machines efficient
in cleaning endoscopes?
Are the programs used in these machines able to
guarantee effective cleaning?
The expert group of the Austrian Society for
Sterile Supply tried to answer these
questions by carrying out studies and
practical tests
Questions/Answers
Do all endoscope WDs which are on the
market comply with the requirements
of the standard ISO 15883?
Unfortunately NO!
Type tests are carried out sporadically and mostly not by
independent accredited laboratories but the companies
themselves.
E.g.: During type testing of an endoscope WD it was
detected, that the 1mm channel was not rinsed at all, but
the machine already had been sold worldwide
Weak cleaning of chambers, outer surfaces
Weak cleaning of channels with an inner diameterof 1 mm or less(e.g. Jet- and Albarran-channel, specialendoscopes)
Malfunction of built-in water softeners
Problems with fittings, connectors, gaskets etc.
Recording without actual values
Wrong failure indication of Flow-Control
Endoscope WDs - Technical
Problems
Missing routine controls regarding:
◦ Cleaning (Cleaning indicators, protein tests)
◦ Dosing system (Change of canisters)
◦ Water quality
◦ Connection between WD and load carrier, loadcarrier and endoscope
Missing validation
Weak or even missing maintenance andcare
Application Errors
Maintenance, Care?
Is the chemistry used in these
machines efficient in cleaning
endoscopes?
Unfortunately
not all of them!
Questions/Answers
Comparative Study on Efficacy of
cleaners
Summary:
Alkaline cleaners were significantly
more effective
Some of the tested cleaners –
especially the enzymatic ones –
showed very low cleaning efficacy
Questions/Answers
Are the programs used in these machines able to guarantee effective cleaning?
Unfortunately not all of them!
Processes in Endoscope Washers too short for
effective cleaning
Temperatures too high (causing denaturation of
proteins)
At 45 °C the results were significantly better than at
58 °C
Both of these facts are crucial especially for enzymatic
cleaners
OEGSV Guideline forTesting, Validation and Control of automatic Cleaning
and Disinfection Procedures of flexible Endoscopes
in accordance with EN ISO 15883- 1, -4 and
CEN ISO/TS 15883-5
www.oegsv.com
Throughout Austria´s hospitals
to a great extent the processes could be optimized according to the criteria specified in
the guideline
OQ Part 1: Commissioning
Control of:
Constructural requirements (seperate
reprocessing room)
Technical requirements (WD +
accessories)
Qualification of director and staff
Quality Management System
OQ: Hygienic Approval of the WD
Control of:
Cleaning efficacy
Disinfection (total germ reduction)
Temperature regulation
Accuracy of display / printout
Dosing accuracy
Water quality
Test pieces:
◦ Dummy with teflon tubes:
Inner diameter 1, 2 and
4 mm simulating the
endoscope channels
Test soil: ◦ Cleaning indicators
Testing: ◦ Connection to nozzles
◦ Interruption of the program
before disinfection stage
Acceptance criteria:◦ No visible residues
Cleaning efficacy „Dummy-Test“
Testing of „Total Bacterial Reduction“
Microbiological Test:
◦ Endoscope dummy with
biological indicators
Test organism:
◦ Enterococcus faecium,
≥ 109 cfu/ml
Testing:
◦ Full cycle (interruption after
last rinsing)
Acceptance criteria:◦ total RF ≥ 9
PQ: Tests on reprocessed Endocopes
Rinsing of channels
Physiologic salt solution
Bacteriological analysis:
Acceptance criteria: ≤10 cfu/ml
Test for protein residuals in
biopsy channel
Appropriate test systems
Acceptance criteria:
< 20 µg/channel
Summary
Validation of the process is essential (acc.
MDD, ISO 15883 part 4, wfhss guideline No. 4)
That means:
Implementation of an adequate QM-System (SOPs,
Documentation etc.)
Upgrading or procurement of endoscope WDs
Implementing routine controls
Qualification of the staff
etc.
Thank you for your attention!