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!