ESGE/ESGENA guideline for process validation and routine testing for reprocessing endoscopes in washer-disinfectors, according to the European Standard prEN ISO 15883 parts 1, 4 and 5

Table of Contents

Contents

1. Scope of this guideline

2. Quality management: the roles of validation and routine testing
3. Responsibilities and qualifications
4. Validation
4.1. Prerequisites
4.2. Installation qualification (IQ)
4.3. Operational qualification (OQ)
4.4. Performance qualification (PQ)
5. Routine testing
6. Frequency
6.1. Frequency of validation and revalidation
6.2. Frequency of routine testing
7. References
8. Appendices
Appendix 1: Glossary
Appendix 2.: Example of a checklist of prerequisites for installation of a washer-disinfector
Appendix 3.: Example of a checklist for installation qualification
Appendix 4.: Example of a checklist for operational qualification
Appendix 5.: Example of a checklist for performance qualification
Appendix 6.: Routine testing: checklist

1. Scope of this guideline

Validation is an important quality assurance tool in hygiene and infection control, whether endoscopy procedures are performed in hospitals, in private clinics, or in doctors’ offices. Up till now, the clinical service provider (see Appendix 1: Glossary) has had to rely on the correct functioning of automated washer-disinfectors according to the manufacturer’s specifications. The current tools for regular quality control are routine maintenance and microbiological surveillance.

Validation procedures have long been common practice in the monitoring of sterilization devices, for example in central sterilization units. The implementation of validation of reprocessing procedures for flexible endoscopes will be an important step for systematic quality assurance and patient safety.

This guideline, from the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA), is based on the European standard, prEN ISO 15883, which describes in detail the design and function requirements for washer-disinfectors. This ESGE/ESGENA guideline addresses the need to validate the entire reprocessing cycle for flexible endoscopes and their accessories, because such validation:

• ensures the transparency of reprocessing procedures

• supports the early detection of weaknesses and defects in washer-disinfectors

• is based on dedicated and proven test methods for benchmarking

• has the potential to reduce the amount of routine testing

This guideline is an expert opinion and provides practical information about and guidance through the validation of the entire procedure of reprocessing with washer-disinfectors. Example checklists are provided to support the implementation of validation at each individual endoscopy unit.

Aims of this guideline

These are:

• To support individual endoscopy departments and clinical service providers in establishing local standards and protocols for validation processes for endoscope reprocessing with washer-disinfectors

• To support national societies and official bodies in developing national recommendations for the validation of procedures for reprocessing flexible endoscopes

Target groups

This guideline provides practical guidance through the validation process for the following groups:

• Clinical service providers, as they have the responsibility to meet structural and organizational requirements and to provide educated staff, for the safe use of washer-disinfectors

• Endoscopists, endoscopy nurses, and other users of washer-disinfectors, who use flexible endoscopes and who are responsible for the safe reprocessing of endoscopy equipment

• Hospital hygienists, microbiological personnel, microbiologists, and authorized agencies, who perform regular microbiological quality control in endoscopy units

• Manufacturers, suppliers, and authorized third parties who sell, install, and maintain flexible endoscopes and washer-disinfectors for gastrointestinal endoscopy

• Institutions, companies, and other qualified agencies that are authorized to perform validation of washer-disinfectors

2. Quality management: the roles of validation and routine testing

The European standard prEN ISO 15 883 consists of five parts, of which three are relevant to endoscopy:

• Part 1 states the general requirements and definitions for all washer-disinfectors.

• Part 4 defines the special requirements for the design of washer-disinfectors and for reprocessing of heat-sensitive instruments such as thermolabile, flexible endoscopes. In addition, prEN ISO 15 883 - 4 requires a check on whether the correct reprocessing results are obtained with all endoscope types to be reprocessed under the particular circumstances obtaining at the service provider’s location (water quality, power supply etc.). This process is called validation.

• Part 5 provides test soils and methods for demonstrating the cleaning efficacy of washer-disinfectors.

Quality assurance systems for washer-disinfectors comprise three parts (see [Figure 1]), type testing, validation, and routine testing.

Figure 1 Quality Management for reprocessing of flexible endoscopes.

1. Type testing according to prEN ISO 15883, is the responsibility of the manufacturer and checks that the washer-disinfector complies with the prEN ISO 15 883 standard. During type testing, each individual step of the reprocessing cycle is separately analyzed (e. g. cleaning efficacy, disinfection efficacy, water quality, chemicals), followed by evaluation of the reprocessing cycle as a whole. In addition, type testing provides reference data for further validation and use of the washer-disinfectors.

2. Validation is the responsibility of the clinical service provider. It demonstrates that the entire reprocessing procedure gives reproducible results at the point of use as required. Single parameters can be defined as indicators. The validation process for washer-disinfectors includes the following steps:

• Installation qualification (IQ), to check that the equipment is received as specified, that it is correctly installed, and that the particular location is suitable for the use of the washer-disinfector

• Operational qualification (OQ), to check that the washer-disinfector will operate as specified in the endoscopy unit concerned

• Performance qualification (PQ), to check that the washer-disinfector consistently performs according to the specification for routine use

Validation must be repeated (revalidation):

• on a regular basis (according to national requirements),

• after each major change of the reprocessing cycle, or

• after major repair.

This is in order to document that the reprocessing process still achieves the same required, reproducible results.

3. Routine testing is the responsibility of the clinical service provider. Based on the validation results, routine tests are established in order to prove that the washer-disinfector works within the defined limits for dedicated parameters and to prove the outcome quality of the complete reprocessing cycle. Routine testing may include tests of endoscopes, washer-disinfectors, and the water used in the particular department. An appropriate sampling plan has to be established for each type of washer-disinfector.

This guideline focuses on the validation process (including installation, operational, and performance qualification) and on the routine testing.

3. Responsibilities and qualifications

It is the responsibility of the clinical service provider to ensure that validation is carried out. Validation must be done at the location where the washer-disinfector is being used. A qualified company/person may carry out validation on behalf of the clinical service provider. It is strongly recommended that the company or persons performing such validation have expert knowledge in all relevant areas such as microbiology, hygiene and infection control, technical and electrical issues relating to washer-disinfectors, chemicals, flexible endoscopes, and regulatory issues.

The clinical service provider must document all the relevant validation data for the washer-disinfector, and the use of standard checklists is recommended. This guideline provides examples of checklists [1] which can be adapted to local structures and the requirements of particular clinical settings (see section 8, Appendices 2 - 6.)

Installation qualification is usually performed by the manufacturer, the supplier, or authorized third parties.

Operational qualification is the responsibility of the clinical service provider. Specialized knowledge will be required about: technical and electrical issues relating to washer-disinfectors; chemicals; flexible endoscopes; regulatory issues; and special equipment. Therefore it is recommended that authorized and specially trained persons perform this validation. The manufacturer of the washer-disinfectors must provide instructions on how to test the various process parameters and functions of each washer-disinfector. The manufacturer may also need to supply appropriate specialized test equipment.

Performance qualification is the responsibility of the clinical service provider. Only persons or organizations with appropriate microbiological expertise should carry out these tests. Additionally, such persons or organizations should have a thorough understanding of the structure and function of the tested washer-disinfectors and endoscopes.

Routine testing is the responsibility of the clinical service provider. The tests may cover technical and microbiological parameters, and should therefore be performed by appropriate trained persons. Collection, culturing, and the interpretation of test results should be done in close cooperation with endoscopy staff, the hospital hygienist, appropriate microbiology personnel, and the microbiologist, in line with national requirements.

An example of the procedures and expertise required for validation and routine testing has been published recently [2]; [Table 1] shows these, linked with the appropriate organizations and personnel needed to carry out the procedures.

Table 1 Responsibilities and Qualification in Quality management of validation

Validation	Responsibility	Option for Execution	Qualification
Prerequisites	Clinical Service Provider	Manufacturer Authorised Supplier Authorised third party	Expertise in regulatory issues technical and electrical issues of WD, chemicals, flexible endoscopes and special equipment
IQ	Clinical Service Provider
OQ	Clinical Service Provider
PQ	Clinical Service Provider	Manufacturer Authorised Supplier Authorised third party, Endoscopy staff Microbiological institutes Microbiological staff Hygienists Infection control nurses	Microbiological expertise Technical understanding of the WD
Routine tests	Clinical Service Provider

4. Validation

4.1. Prerequisites

The endoscopy department or unit must fulfil technical and organizational prerequisites. A purpose-designed room for cleaning and disinfection that is separate from procedure rooms is recommended, to minimize patient and staff exposure to:

• chemicals used in cleaning and disinfection procedures (e. g. because of toxic/allergic reactions, glutaraldehyde vapour)

• the risk of infection and contamination with potentially infectious material, blood and other body fluids.

The manufacturer must provide information about the structure and function of the washer-disinfector. The validation can be performed when the washer-disinfector is installed according to the manufacturer’s instructions and local safety regulations, and when all components and utilities are available.

The checklist in Appendix 2 is an example of what should be considered. It is based on the recommendations of the ESGE Guidelines Committee and relevant European guidelines [3] [4].

4.2. Installation qualification (IQ)

Installation qualification is the process of obtaining and documenting evidence that the washer-disinfector has been supplied and installed in accordance with its specifications. Checks need to be carried out that all ordered items have been received and that the location of the washer-disinfector correctly fulfils specifications (e. g. with regard to water quality, power supply, etc.). An example of a checklist is shown in Appendix 3.

4.3. Operational qualification (OQ)

Operational qualification is the process of obtaining and documenting evidence that the installed washer-disinfector operates within predetermined limits when used in accordance with its operational procedures. For example, checks are needed to show whether:

• the leak test and the flow control function in accordance within their specifications,

• the temperature profile is in line with specifications, and

• the dosage pumps for the chemicals deliver the right quantities.

A standardized checklist is available in Appendix 4.

4.4. Performance qualification (PQ)

Performance qualification is the process of obtaining and documenting evidence that the washer-disinfector, as installed and operated in accordance with operational procedures, consistently performs in accordance with predetermined criteria and thereby yields reprocessed instruments according to the specifications.

Performance qualification focuses on the testing of the washer-disinfector in operational conditions. The efficacy of the cleaning and disinfection steps should be evaluated as a combined test procedure.

The prEN ISO 15 883 - 5 standard offers a variety of test soils and methods for demonstrating cleaning efficacy, but there is currently no consensus in the relevant working group of the CEN (Comité Européen de Normalisation/European Committee for Standardization) regarding preferred test soils and methods. Therefore, the present guideline only recommends that they should be carried out on endoscopes that are routinely used in clinical practice and should include representative samples of all types of endoscopes used and reprocessed in the particular department.

The endoscopes employed in the performance qualification procedure should be used in clinical practice and should be reprocessed following the everyday standardized reprocessing protocol, including pre-cleaning by brushing manually and cleaning and disinfection in the washer-disinfector. This will ensure that potential negative side effects of incompatible chemicals are identified.

National guidelines and laws on validation and hygiene in endoscopy vary from country to country [5] [6]. Test procedures for performance qualification have to be modified according to national regulations. This guideline includes suggestions for testing important process parameters.

Test condition procedures for evaluating the results and to achieving limits are available in Appendix 5.

5. Routine testing

Routine testing ensures that the required performance standard is delivered consistently at all times.

Based on the individual risk assessment and the results of the validation of each individual machine, the extent of the routine testing has to be defined, based on national recommendations and prEN 15 883/4 Annex C. These routine tests cover technical and microbiological parameters.

Routine checks of technical parameters (such as leakage testing and channel non-obstruction testing, and of temperature, water quality, etc.) can reduce the required number of microbiological tests on endoscopes, as the technical tests demonstrate that the washer-disinfector is working within its specifications. In addition paper print-outs document that the particular reprocessing cycle has been completed within the required process parameters. Daily check-ups of single machine parameters document that the washer-disinfector operates within its specifications. These daily check-ups may be defined by the manufacturer or the service provider.

For performance of microbiological tests on endoscopes, it is recommended that the ESGE-ESGENA guideline on microbiological surveillance testing in endoscopy is followed [7].

If any routine test result breaches the specification (because it is out of the predetermined range of the technical parameters or because of contamination), it is the responsibility of the clinical service provider to take the suspect device out of service (e. g. washer-disinfector, endoscope), until corrective actions have been taken and satisfactory results have been achieved.

Examples of possible test options are given in Appendix 6.

6. Frequency

6.1. Frequency of validation and revalidation

A complete validation is necessary before routine use. This first validation is a baseline assessment of the adequacy of effectiveness (prEN ISO 15883-4).

A revalidation is necessary after any major repair, change, or both of the reprocessing cycle (e. g. in temperatures, process chemicals).

Regular maintenance of washer-disinfectors is part of quality management and is a prerequisite for their safe use. It ensures the early detection of possible weaknesses and defects in washer-disinfectors.

6.2. Frequency of routine testing

In order to confirm the correct functioning of the washer-disinfectors, routine testing on a regular basis according to national requirements is recommended. The frequency of routine microbiological tests can be reduced if the machine consistently shows reliable technical results on routine tests. It is the responsibility of the clinical service provider to decide on the intervals between microbiological tests.

The frequency of routine microbiological testing varies across Europe [7]. This guideline therefore will have to be modified locally to comply with the relevant national regulations. As a point of reference, the ESGE-ESGENA Guideline Committee recommends routine testing every 3 months at least.

8. Appendices

The tables and checklists in Appendices 2 - 6 are based on the German Guideline for alidation of automated reprocessing processes or thermostable medical devices [6].

Appendix 1: Glossary

Clinical service provider: An organization, person, or persons legally responsible for the provision of a clinical service. Could be an institution (such as the health service), hospital or department, or a doctor working in his own premises.

User: Person or department using equipment; organization(s) or persons within those organization(s) who operate and/or use the equipment

Process chemicals: All chemicals used during the reprocessing procedures, including detergents, disinfectants, alcohol, etc.

Appendix 2: Example of a checklist to evaluate the prerequisites for installation of a washer-disinfector

Part 1 Environmental and structural prerequisites for the clinical service provider

Requirement	Available	Countermeasure, Comments
Purpose-designed reprocessing room, separate from procedure rooms
Separation of contaminated and clean working areas
Information about water quality (e. g. hardness and microbiological status)
Trap (U-bend) in drainpipe
Ventilation of reprocessing room
Room temperature conditions defined
Isolating valve and dirt arrester for cold water
Isolating valve and dirt arrester for warm water
Isolating valve for demineralised water
Mains switch for electrical power supply
Device for hand disinfection
Storage for process chemicals, safe supply
Health and safety requirements

Part 2 Organizational prerequisites for the clinical service provider

Requirement	Available	Countermeasure, Comments
Reprocessing instructions for each medical device
Risk analysis for reusable medical devices (with respect to hygiene)
Medical device file and manual for WD, including description of the entire reprocessing procedure
Maintenance and service schedule for washer-disinfectors
Safety data sheets for all process chemicals
Definition of test load for performance qualification
Definition of person responsible for performance qualification
Certification of reprocessing staff (training courses, competency assessment)
Hygiene plan and reprocessing protocols
Compatibility of WD, endoscopes and process chemicals

Appendix 3: Example of checklist for installation qualification

General Information about the washer-disinfector

Installation location
Person responsible for validation
Further responsible persons
Date of validation
Type of device
Manufacturer
Serial number
Year of production

Part 1 Delivery contens

Products ordered	Article number	Amount	received products	Damage (Yes/No)

Process chemicals		Applicable (Yes/No)
No.	Product name	Manufacturer	Function
1
2
3

Part 2 Documentation

Type/Title	Delivered (Yes/No)	Document no.	To be filed at:
Installation plan
Circuit diagrams
Instruction manual
Other manuals (i. e. Maintenance)
Safety data sheets of chemicals
Reports and certificates
Declaration of conformity MDD 93/ 42

Part 3 Responsible Departments/Companies. All internal departments and external companiesin charge of preparation of the installation site and maintenance shall be listed

Type of installation and installation task	Department/Company	Date of Installation
Electrical power supply
Water supply
Drainage
Air ventilation

Appendix 4: Example of a checklist for operational qualification

General information about the washer-disinfector

Device
Location of installation
Person responsible for validation
Date of validation

Part 1 Basic functions

Requirement	Applicable	OK	Not OK	Comments, Countermeasure
Check all water supply pipes in leakage concerned
Check drainage pipes for buckling
Check power supply; connectors available
Check all door seals for leakage
Check all sieves and filters (outside washer-disinfector), sterile filters for availability and leakage
Check all sieves and filters (inside washer-disinfector) for availability and dirt
Check spray arm for availability, check rpm*
Check liquid level sensor
Check function of scope identification
Check functionality of documentation (printer or network connection)
Check all adapters (position and function)
Check leak test adapters (position and function) and endoscope connection
Check external ventilation (if required)
Check door lock of washer-disinfector, function, seals
Check whether START of process is blocked if washer-disinfector door is still open
Check filter efficacy (chemicals, vapour etc)
* rpm, revolutions per minute

Part 2 Operational functions

Water supply:			Applicable (Yes/No)
Name/No. of process
Water Supply	Process cycle	Specified volume range*, L	Measured volume, L	Comment
	Pre-cleaning
	Cleaning
	Rinsing
	Disinfection
	Rinse 1
	Rinse 2
	Rinse 3
* As specified in type testing of each individual washer-disinfector

Temperature:			Applicable (Yes/No)
Name/No. of process:
Temperature	Process cycle	Specified temperature range*, °C	Measured temperature, °C	Comment
	Pre-cleaning
	Cleaning
	Rinsing
	Disinfection
	Rinse 1
	Rinse 2
	Rinse 3
	Drying
* As specified in type testing for each individual washer-disinfector

Dosage process chemicals:			Applicable (Yes/No)
Dosage	Product no./name of product	Specified range of volume*, ml, tolerance	Measured volume, ml	Comment
	1
	2
	3
* As specified in type testing for each individual washer-disinfector

Part 3: Machine and alarm functions

Requirement	Applicable	Ok	Not Ok	Comments, Countermeasure
Alarm function: Leak test NOK (simulation leak)
Alarm function: channel non-obstruction test
Alarm function: Insufficient dosage
Alarm function: No process chemicals
Alarm function: Water supply
Alarm function: Temperature
Documentation (process print-out)
Cycle completion 1 ( pass function); Cycle completion 1 (fail function); Documentation of temperature profile				Name Prog. 1
Cycle completion 2 ( pass function); Cycle completion 2 (fail function); Documentation of temperature profile				Name Prog. 2
Cycle completion 3 ( pass function); Cycle completion 3 (fail function); Documentation of temperature profile				Name Prog. 3

Appendix 5: Example of a checklist for performance qualification

General information

Location of installation
Person responsible for validation
Date of validation
Persons collecting the test samples
Institution and persons performing culturing
Type/Article of tested endoscope
Serial number of tested endoscope
Date of last reprocessing cycle
Washer-disinfector used for last reprocessing cycle (article, serial number)
Type/Article of tested washer-disinfector
Serial number of tested WD

Part 1: Microbiological tests

	Sample number	Volume of sterile saline used	Results - Specification of microorganisms found - Number of cfu*
1. Test of Endoscope 1.1. Endoscope channels - Suction/instrument channel - Air-water-channel - Elevator channel - Separate flushing channels
1.2. Swabs from endoscopes surfaces - Control part - Distal end - Channel openings - Elevator on duodenoscopes
2. Test of washer-disinfector - Sample from last rinsing water from washer-disinfector
* cfu, colony-forming units

Appendix 6: Routine testing - checklist

General information

Installation place
Person responsible for validation
Date of validation

Part 1: Technical tests (examples of possible test parameters):

Name/No. of washer-disinfector and process:
Temperature	Process cycle	Specified temperature range*, °C	Measured temperature, °C	Comment
	Cleaning
	Disinfection
	Drying
* As specified in type testing of each individual washer-disinfector

Part 2 Machine and alarm functions (examples of possible alarm functions):

Requirement	Applicable	Ok	Not Ok	Comments, Countermeasure
Alarm function: Leak Test NOK (simulation leak)
Alarm function: channel non-obstruction test
Alarm function: Insufficient dosage
Alarm function: Water supply
Documentation (process print-out)

Part 3 Microbiological tests

Persons collecting the test samples
Institute and persons performing culturing
Type/Article of tested endoscope
Serial number of tested endoscope
Date of last reprocessing cycle
Washer-disinfector used for last reprocessing cycle (article, serial number)
Type/Article of tested washer-disinfector
Serial number of tested washer-disinfector
	Sample number	Volume of sterile saline used	Results - Specification of germs founded - Number of cfu*
1. Test of Endoscope 1.1. Endoscope channels - Suction/instrument channel - Air/water channel - Elevator channel - Separate flushing channels
1.2. Swabs from endoscopes surfaces - Control part - Distal end - Channel openings - Elevator on duodenoscopes
1.4. Water bottle - Water sample from used bottle
2. Test of washer-disinfector Sample of final rinsing water from washer-disinfector
* cfu, colony-forming units

7. References

• 1 DGVS . Leitlinie von DGKH, DGSV und AKI für die Validierung und Routineüberwachung machineller Reinigungs- und Desinfektionsprozesse für thermostabile Medizinprodukte und zu Grundsätzen der Geräteauswahl.  Zentralsterilisation. 2005;  13 Suppl 1 1-33
• 2 DGSV (Deutsche Gesellschaft für Sterilgutversorgung [German Society for Sterile Supply]) . Qualification requirements for persons entrusted with validation.  Zentralsterilisation. 2005;  13 375-376
• 3 ESGE-ESGENA Guideline Committee . Guidelines on cleaning and disinfection in gastrointestinal endoscopy - update 1999.  Endoscopy. 2000;  32 77-83
• 4 ESGE-ESGENA Working Group . ESGE-ESGENA checklist for purchase of washer disinfectors for flexible endoscopes.  Endoscopy. 2000;  32 914-919
• 5 Rey J F, Kruse A. Cleaning and disinfection in Europe according to the Endoscopic Societies’ guidelines.  Endoscopy. 2003;  35 878-881
• 6 Leiss O, Beilenhoff U, Bader L. et al . Reprocessing of flexible endoscopes and endoscopic accessories - an international comparison of guidelines.  Z Gastroenterol. 2002;  40 531-542
• 7 ESGE/ESGENA guideline for quality assurance in reprocessing: microbiological surveillance testing in endoscopy.  Endoscopy. 2007;  in press