Cost Effective Validation of Sterilising Processing Equipment

Northern Sydney Central Coast Area Health Service

Abstract

Australian/New Zealand Standard 4187 mandates minimum standards that must be met by Sterilising Services in Health Care facilities which provide Clean, Disinfected or Sterilised Medical and Surgical Equipment for use in patient care. The section on Quality Management states that Validation Testing must be conducted and documented for Sterilisers, Washer Disinfectors and other associated equipment. Validation is performed to evaluate the reliability of the Cleaning, Packaging and Sterilisation process.

The requirement for Validation was introduced in 2003 with suppliers of the various types of equipment providing a limited validation service which had the potential to become very costly as validation must be carried out on Commissioning, then Annually and after Major Repairs. The Sterilising Services Business Unit identified an opportunity to utilise the additional specialised skills of a Sterilising Technician with an Engineering background to develop a comprehensive validation system which would not only met the requirements of the Standard for Northern Sydney Central Coast Area Health Service but have the potential to be outsourced to other NSW Area Health Services. The system was developed in partnership with the Biomedical Engineering Department using non wireless technology.

Aim

To deliver a validation system that provides a cost effective comprehensive evidence of compliance of product and process by the validation and revalidation, performance monitoring, maintenance of sterilising equipment and Quality Management requirements of AS 4187.

Nature of the Problem

Sterilisation of medical devices is a complicated process and with the emergence of new Surgical Technologies and Techniques, Instruments and Equipment requiring sterilisation is becoming more difficult to clean and sterilise. Validation and revalidation will ensure that Equipment and Process performance maintains the Sterility Assurance Level (SAL) of 10 – 6 of processed medical devices.

Extent of the Problem

Most Sterilising Services have up to four mechanical washers, two dryers and four steam sterilisers. The equipment needs to be validated and revalidated to ensure the performance is maintained and meets the minimum requirements of AS/NZ 4187, ISO14937, PD2007_036 and other related standards.

An initial costing of validation performed by a contractor for the 7 Sterilising Services Departments in NSCCAHS was conducted which indicated $150,000 per annum for annual validation only; it did not incorporate validation for Major repairs. Cost for NSCCAHS to perform the Service is $95,000 saving $55,000 per annum.

Is the project adaptable across other Area Health Services?

The system is adaptable and the technology is readily available and could be enhanced to provide a mechanism for research in the Cleaning and Sterilisation process.

Strategic Importance

The validation equipment was developed in conjunction with the Biomedical Engineering Department and comprises of 13 sensors (12 x temperature and a pressure sensor). The sensors are NATA certified and required to be re-certified annually. 

These sensors were fitted in a conical fitting and were tested and certified to meet the boiler pressure requirements.

The conical fitting is simply plugged into the steriliser’s gland entry, standard to all hospital steam sterilisers. The probes are then fed and airtight / sealed using a butterfly clamp and rubber seal O-ring. A Leak Rate Test and a Bowie Dick Test follows and should ensure a pass results to guarantee correct functionality of the steriliser. The validation or revalidation of selected sterilisation process, load configuration and loading pattern can then commence and data and test results will be comprehensively analysed and interpreted. The temperature probes are not only used for the sterilisers but have the capability in validating other sterilisation related equipment such as washers, dryers and others.

Planning and Implementing Solutions

Initial presentation of the validation equipment and process was conducted at the Royal North Shore Hospital and attended by the Director of the Sterilising Services Business Unit (SSBU), Departmental Managers and Sterilising Technicians. It was also an open forum to discuss issues and advantages of the validation equipment.

The NSCCAHS Sterilising Services Business Unit has established a Working Party to address and collectively develop policies and procedures which includes the Validation of the Sterilising Process and Related Equipment. The Working Party comprises of the Director of SSBU, ISO Coordinator, all sites departmental Managers and Sterilising Technicians.

A plan or schedule will be established for all 7 Sterilising Services Departments across NSCCAHS. Training is also being provided to Sterilising Technicians to assist in the implementation of the program across sites with the assistance of the Biomedical Engineering Department.

Outcomes and Evaluation

The validation equipment generates data which can be stored digitally and is easily accessible by the area health service and provides reliable traceability of compliance to patient records

The validation system also has the capability which can be utilized in research of sterilisation performance including medical devices and related products sterilised or exposed to the said sterilisation process.

Above: Wet packs will be addressed and eliminated during the validation process and a disintegrated wrapping material exposed to extreme UV light and weather.

The data collected during the validation will be thoroughly analysed to detect anomalies. Figure 1 is a sample of a graph showing fluctuations or unstable pressure – temperature relationship which suggests that the steam steriliser’s Steam Reducer valve may require adjustment. Although the results have passed after comparison with NATA certificates and required adjustments, the sterilisation process is in the brink of failure and could result to future anomalies in the short to medium term. By comparison, after necessary adjustment was performed of the same sterilisation process, Figure 2 is a sample graph which suggests that the sterilisation stage is more stable and consistent with the pressure - temperature relationship indicating a steady functionality and stabilization of sterilisation stage. These are just some few advantages of performing the validation or revalidation of sterilisation equipment. 

Sustaining Change

Using the validation equipment continuously under rough environmental conditions will result to wear and tear or shorter life span of the hard wares, therefore regular checks and re-certification of the testing equipment shall be maintained in order for the equipment to be confidently and continuously reliable and sustainable. However, replacement is inexpensive and readily available in the market.

Future Scope

The application of the validation system is not only limited to the Sterilising Services Departments throughout NSW Area Health Services but also expandable to Private Hospitals, General Practices and Dental practices. Other applications could also include bench top sterilisers used by Dental and General Practices, aeration cabinets, container systems, benchmarking in the sterilisation of medical devices e.g. cannulated medical devices and any related products used in sterilisation process to name a few.
Having established a sustainable validation system and proven parameters and procedures would not only necessitate validation and revalidation as a norm throughout the NSW Health but also ensure the Quality management system is maintained with confidence.

References

1. AS 1410-2003. Sterilisers-Steam-Pre-vacuum. Standards Australia, Sydney.
2. AS ISO 11135-2002. Medical devices - Validation and routine control of ethylene oxide sterilisation. Standards Australia, Sydney.
3. AS ISO 13485-2003. Medical devices - Quality management systems - Requirements for regulatory purposes. Standards Australia, Sydney.
4. AS / NZ 4187:2003. Cleaning, disinfecting and sterilising reusable medical and surgical instruments and equipment, and maintenance of associated environments in health care facilities. Standards Australia, Sydney.
5. AS / NZS ISO 9001:2000. Quality management systems - Requirements. Standards Australia, Sydney.
6. Australian Government (2004). Department of Health and Ageing. Infection Control Guidelines for the prevention of transmission of infectious diseases in the health care setting.
7. BS EN ISO17664:2004. Sterilisation of medical devices - Information to be provided by the manufacturer for the processing of re-sterilisable medical devices. International Standards Organisation, Switzerland.
8. ISO 14937 - Sterilisation of health care products - General requirements for characterisation of a sterilising agent and the development, validation and routine control of a sterilisation process for medical devices. International Standards Organisation, Switzerland.
9. NSW Department of Health (2005). Sterilising Audit / Action Plan. Sterilising Audit to Comply with AS/NZ 4187:2003. NSW Health, Sydney.
10. NSW Department of Health (2007). Policy Directive 2007_036. Infection Control Policy. Internet Accessed [07 February 2008].
11. Standards Australia and Standards New Zealand (2003). Australian/New Zealand Standards AS/NZ 4187. Cleaning, disinfecting and sterilizing reusable medical and surgical instruments and equipment, and maintenance of associated environments in health care facilities. Standards Australia, Sydney.
12. Standards Australia and Standards New Zealand (2001). Australian/New Zealand Standards AS/NZ 4185. Office-based health care facilities involved in complex patient procedures and processes – Cleaning, disinfecting and sterilizing reusable medical and surgical instruments and equipment, and maintenance of associated environments. Standards Australia, Sydney.
13. Gardner, J. F., et. Al. (1998). Sterilization, Disinfection and Infection Control (3rd Ed.). Sydney, Churchill Livingstone.
14. Standards Australia (2003). Australian Standards AS 1410. Sterilizers – Steam – Pre-vacuum. Standards Australia, Sydney.
15. Standards Australia (2002). Australian Standards AS 2192. Sterilizers – Steam – Downward-displacement. Standards Australia, Sydney.
16. Standards Australia (1993). Australian Standards AS1079.1. Packaging of items (sterile) for patient care. Part 1: Selection of packaging materials for goods undergoing sterilization. Standards Australia, Sydney.
17. Standards Australia (1994). Australian Standards AS1079.5. Packaging of items (sterile) for patient care. Part 5: Non-reusable, non-woven wrapping materials – For goods undergoing sterilization in health care facilities. Standards Australia, Sydney.
18. International Standard (1995). ISO 11140-1. First Ed. Sterilisation of health care products – Chemical Indicators. Part 1: General requirements. ISO, Switzerland.
19. International Standard (1995). ISO 11138-3. First Ed. Sterilisation of health care products – Biological Indicators. Part 3: Biological indicators for moist heat sterilisation. ISO, Switzerland.
20. Standards Australia (1986). Australian Standards AS2853. Enclosures- Temperature –controlled – Performance testing and grading. Standards Australia, Sydney.
21. Standards Australia (1999). Australian Standards AS2514. Drying Cabinets for Medical Equipments. Standards Australia, Sydney.
22. Standards Australia (2002). Australian Standards AS2945 (Int). Batch-type washer/disinfectors for health care facilities. Standards Australia, Sydney.
23. The University of Edinburgh (2005). Health and Safety Department. Autoclaves. Validation and Routine Monitoring of Autoclave Performance. Internet Accessed [04 June 2008].
     Available from: http://www.safety.ed.ac.uk/resources/Bio/Guidance/General/autoclaves.shtm.

Contact

This project was entered in the 2008 NSW Health Awards, Make Smart Choices about the Costs and Benefits of Health Services category.

More about the 2008 NSW Health Awards