Decon sciences Flashcards
lifecycle of re-usable surgical instruments
cleaning
disinfection
inspection
packaging
sterilisation
transport
use
storage
transport
What is a critical device?
a device that penetrates soft tissue, makes contact with bone and enters or contacts the bloodstream or normally sterile tissue
How should a critical device be processed?
device must be cleaned then sterilised
give examples of critical devices
surgical and biopsy instruments
forceps
what is a semi critical device?
a device that comes into contact with non-intact skin or mucous membrane, but does not penetrate soft tissue or make contact with the bloodstream, bone or normally sterile tissue
how should a semi-critical device be processed?
the device must be cleaned and subject to high-level disinfection
give an example of semi-critical devices
dental mirror
anaesthetic syringes
what is a non-critical device?
a device that only comes into contact with the skin and intact mucous membrane
how should a non-critical device be processed?
cleaning followed by low level disinfection
give an example of a non-critical device
chair light handle
Why must instruments be cleaned as the first stage? (5 reasons)
functionality of instrumentation
minimise spread of contamination
prevent failed procedures
achieves steam contact
it is a legal requirement
What is the recommended cleaning method for dental instruments?
a washer disinfector
what is the secondary (back up) method for cleaning dental instruments
ultrasonic bath
What are the 3 types of sterilisers?
type B = vacuum
type N = non vacuum
type S (used for specialised pieces of equipment)
What are the 2 manual cleaning methods?
immersion
non-immersion
indications for carrying out manual cleaning
recommended by manufacturers instructions
no other alternative
automated process of the ultrasonic or washer-disinfector has failed to remove contamination
what are the 5 stages of an AWD? what does each stage do
flush/prewash
- removes gross contamination
main wash
- supplemented by detergent to more efficiently remove biological matter
rinse
- removes any remaining biological or chemical residue prior to disinfection
thermal disinfection
- actively kills micro-organisms with the use of heated water
drying
- removes moisture from surface of instruments through use of hot air
Time and temperature of the thermal disinfection stage
90-95 degrees for minimum of 1 minute
daily checks required for Washer-disinfector
check that the spray arms spin freely without obstruction
check the spray jets are not blocked
make sure that there is no debris on the filter
check the condition of the door seal
- wipe clean if necessary
ensure there is an adequate amount of chemical in the reservoir
record the disinfection temperature of the first cycle every day
Why is steam used for sterilisation?
steam carries a massive amount of energy
it is a non-toxic component in the sterilisation process
for certain applications it can be recondensed and used again
the main ingredient is water = readily available
no waste product except water
what are the 4 types of purified water
reverse osmosis
de-ionised
distilled
sterile
How does a type n steriliser work?
machine heats water in the chamber
as it turns to steam it passively forces the air from the chamber
disadvantages of a type n steriliser
process can leave pockets of air within chamber
- not entirely sufficient
not favourable for a high quality sterilisation process
cannot processed wrapped, channelled or lumened instruments
instruments processed this way are sterilised - NOT sterile at the point of use
type N steriliser - required temperature, pressure and time
134-137 degrees Celsius
2.05-2.35 bar gauge
minimum stage hold time of 3 minutes
how does a type B steriliser work?
all air removed fro chamber
chamber filled with steam
- as air has been removed first, a vacuum has been created
steam rushes into chamber effectively contacting all surfaces
- has the capability to penetrate wrappings of instruments and sterilise the inside of the instruments
type B steriliser required temperature, pressure and time
must achieve 134-137 degrees C at 2,05-2.35 bar gauge (3.05-3.35 absolute pressure) for at least 3 minutes
daily checks for a steriliser include:
checking door seals are intact and free from debris
- clean if necessary
verify chamber is free from damage, debris, contamination or instruments from previous cycle
fill and drain feed water reservoir each day
drain the used water reservoir each day
specific type B steriliser daily test
steam penetration test
Bowie dick test pack
OR
helix
specific type b steriliser weekly tests
an air leakage test
an air detector function test
(both tests are machine cycles)
what are the elements of the sinner circle?
energy
time
temperature
chemicals
what pressure is used in a washer disinfector?
1-1.5 bar (2 - 2.5 bar absolute)
guidance for decontamination is called…
SHTM - Scottish health technical memorandum
how long do decontamination records need to be stored for?
25 years
top 5 causes of dental handpiece faults
incorrect or inadequate lubrication
poor or inadequate cleaning, including incorrect processing
incorrect instrument usage
damaged or oversized bur fitted
incorrect compressor settings and lack of maintenance
Washer disinfector loading requirements
the available load carrier furniture must be used
clip trays must be used and positioned correctly
no overlapping or shadowing of equipment
hinged instruments much be opened at the hinge
all assemblies should be disassembled beforehand
What is used to inspect instruments after the WD cycle?
an illuminated magnifier
