Objectives: Steam Sterilization (2-12 and pg. 60)
decontamination
reduction of pathogenic microorganisms to a level at which items are safe to handle without protective attire
disinfection
kills large numbers, if not all, of the targeted pathogens but typically do not kill large numbers of spores
sterilization
complete elimination of viable organisms including spores and, as such, is the highest level of pathogen control
autoclave
the device used for steam sterlization
biological indicator
test systems that contain something living.
the only way to make sure that sterilization is complete
Understand why Geobacillus stearothermophilus is used to test the efficacy of autoclaves
they are the most resistant organism to steam autoclaving, so if they are killed then the autoclave works.
Understand how an autoclave achieves sterilization
it uses super heated steam under pressure to kill heat resistant organisms
Identify the minimum time and temperature for effective sterilization using an autoclave
15 minutes at 121 C
Identify the minimum time and temperature recommended by WHO for use in clinics, hospitals and other locations using surgical instruments. Understand why this would be the case
134 degrees C for 18 min
because surgical instruments are being processed
Understand why sterilizing time may need to be increased from the minimum to effectively sterilize a particular load
to make sure that all vegetative cells and spores have been killed and that items deep inside the autoclave container that may be partially insulated from the steam by surrounding items are all sterilized
Understand how the BT-Sure biological indicator system is used to test the efficacy of an autoclave. (Don’t forget the controls and their purpose.)
If the spores are killed in the BT-Sure test, it is safe to say that other organisms will be killed as well in the autoclave. It is a good test for testing the efficacy of the autoclave in this way.
Identify the components of the BT-Sure biological indicator system and the purpose of each component. (e.g. ampule of media, strip of paper, pH indicator)
BT-Sure has an ampule of fermentation broth media in it. The top of the BT-Sure has holes in it to allow air in. You break the ampule and the organism (with spores) that is on filter paper grows in the medium. This is incubated. Strip of paper is the autoclave tape. Turns from blue to black when autoclaved. pH indicator is a biological indicator turns yellow or purple.
Be able to accurately interpret the results of a BT-Sure test
Yellow result - is not autoclaved (evidenced by blue band of color strip too) and fermentation/acid production is in the medium. the organism is alive.
Purple result - is autoclaved (evidenced by grey strip) and there is no fermentation/acid production in the medium. the organism is dead.
Why is simply reading the color of the band on the BT-Sure vial not an accurate indicator of the effectiveness of the autoclave?
Because spore producing thermophiles love heat and are hard to sterilize and kill
Identify the one disease causing particle that cannot be reliably inactivated by steam sterilization alone. What is the recommended process for decontaminating surgical instruments suspected of harboring this pathogen?
Prion proteins