Lets Talk Indicators Challenging the process Sterilization ICAN 5 th November Peter Newson
Objectives In the context of the Decontamination process what is an indicator? What phases of the process do we want to monitor and in accordance with which standards? Sterilization - Steam daily machine release Sterilization Steam process, load and tray monitoring Conclusion
Indicators - monitoring of which phase of the process Cleaning is the process that physically removes soiling including large numbers of microorganisms and the organic material on which they thrive. Disinfection describes a process that eliminates many or all pathogenic microorganisms with the exception of bacterial spores. Sterilisation refers to a physical or chemical process that completely kills or destroys all forms of viable microorganisms from an object, including spores.. Organic Matter Surface If it's not clean... it can't be sterile (Spaulding) Infectious Microorganisms
Daily testing of your steam sterilizer - What do the standards say?
In the context of the EN ISO 17665 standard what is a Bowie and Dick test? The Bowie Dick test is a daily steam penetration test that is performed at the commencement of each day that the steam sterilizer is used. It is a requirement of EN ISO 17665-1 to perform this test. ( if an alternative Bowie and Dick test is used this must comply to all criteria as stipulated in EN ISO 11140-4)
Daily test - Bowie and Dick Test
Alternative Bowie and Dick tests BSI EN ISO 11140-4 11140-4 requires that alternative Bowie Dick products have equivalent performance to the towel pack Reference pack (towel pack) and alternative are tested alternately in both good pass cycles and corrupted fail cycles
VACUUM PULSE REMOVING AIR AIR AIR AIR MASS AIR
STEAM SURROUNDS THE MASS MASS
ATTRACTION OF STEAM THROUGH CONDENSATION STEAM STEAM CONDENSATE MASS STEAM STEAM
VACUUM PULSE REMOVING AIR, STEAM AND CONDENSATE AIR, STEAM & WATER MASS AIR, STEAM & WATER AIR, STEAM & WATER AIR STEAM & WATER
SUCCESSFUL PENETRATION OF STEAM TO CENTRE OF MASS STEAM MASS STEAM STEAM STEAM
Insufficient air removal, air leaks and poor steam quality AIR/GAS POCKET STEAM MASS STEAM STEAM STEAM
Four Key Requirements for a Bowie Dick Test Porosity Density Insulation Mass
Sterility Assurance The Sterility Assurance Level, or SAL, is a measure of the confidence in the attainment of sterility a probability of 1 unsterile load in 1,000,000
No. of Micro-organisms 10 6 10 5 10 4 10 3 10 2 10 1 10 0 10-1 10-2 10-3 10-4 10-5 10-6 Safety Time Assumed Bioburden of 10 6 Micro-organisms 0 1 2 3 Mins. SAL 10-6 Minimum of 1 Min. Safety Time
No. of Micro-organisms Biological indicators 10 6 10 5 10 4 10 3 10 2 10 1 10 0 10-1 10-2 10-3 10-4 10-5 10-6 Assumed Bioburden of 10 6 Micro-organisms 0 1 2 3 Mins.
Classification of indicators recent changes in thinking EN ISO 11140-1
ISO11140 - Classifications Class 1: Process indicators Class 2: Indicators for use in specific tests Class 3: Single parameter indicators Class 4: Multi-parameter indicators Class 5: Integrating indicators Class 6: Emulating indicators
Class 3 and Class 4 Class 3 indicators Prove that one or more parameters of the sterilization process such as temperature or time were present Class 4 indicators Prove that 2 or more of the parameters of, temperature, steam and time were present. Tolerances are: Time +0%, to - 25% Temperature +0, to -2C
ISO11140 - Class 5 Integrating Indicators Also known as chemical biological indicators Must react to all critical parameters of a given process Follow the death curve of a given spore population, e.g. G. stearothermophilius in steam as per ISO 11138 part 3 For steam the tolerances are; time +0%, - 15% temperature +0, -1C
No. of Micro-organisms Class 5 indicators at 134 C 10 6 10 5 10 4 10 3 10 2 10 1 10 0 10-1 10-2 10-3 10-4 10-5 10-6 Assumed Bioburden of 10 6 Micro-organisms 0 1 2 3 Mins.
Class 5 endpoint DRAIN PACK
Class 6 A Class 6 indicator would prove that all parameters of a given process were present as per values stated on the indicator. Monitoring all 3 critical parameters of Time, Temperature and Steam Cycle emulating For steam the tolerances are; time +0%, - 6% temperature +0, -1C Some examples :134 C for 3.5, 4, 5.3, 7, and 18 m - 121 C for 12, 15 and 20 min
No. of Micro-organisms Class 6 10 6 10 5 10 4 10 3 10 2 10 1 10 0 10-1 10-2 10-3 10-4 10-5 10-6 Assumed Bioburden of 10 6 Micro-organisms 0 1 2 3 Mins. SAL 10-6 Minimum of 1 Min. Safety Time
What does this mean? Class 5 endpoint Class 6 endpoint 5.3 min 134 C DRAIN PACK
Classifications and the FDA The FDA recognises Process indicators - Class 1 Air removal indicators for test packs - Class 2 Chemical integrators - Class 6 The FDA does not recognise Class 3 single parameter indicators Class 4 Multi parameter indicators Class 5 integrating indicators
In conclusion Do we need to monitor the decontamination process? Simply because it is a process with all the variables and contributing factors that can influence a process it is imperative that you consistently provide end-users and your facilities with the evidence of the efficacy of the reprocessing of your hospitals instruments Thank you very much!!!