judgement day: the machines have taken over Flashcards
what does AWD stand for
Automatic Washer-Disinfectors (AWD)
what is there a legal requirement about with regards to AWD
Now a legal requirement for us to operate a WD and process our contaminated instruments through one
What does IQ OQ PQ stand for
Installation Qualification Operation Qualification Performance Qualification
what is IQ OQ PQ relevant for
These are in relation to the installation of any type of equipment in a decontamination environment and they will be put through these 3 expected qualifications to ensure the machine is operating correctly and these will need to be carried out be a competent person and they also need to be approved by an authorising engineer for decontamination [AE(D)]
with regards to AWD what is the chamber
where the process takes place and all the different stages of it as well
what is the load carrier
piece of equipment where we set out contaminated instrumentation to process it through the machine
what is the control panel
For starting cycles / operating the AWD
There is a little screen on the upper part of it as well that offers forward information such as the stage that it is currently on, the time its been processing and the temperature that the current stage is at as well
what are the pros and cons of manually washing instruments
• There is the potential for human error
• There can be variance of efficacy depending on the operator
○ Different people carrying out this process might not be doing it the exact same way
• They have significantly larger mechanical force
But that means you need to have an operator manually cleaning
what does the automated process of washer-disinfectors do
Washer-disinfectors have an automated process meaning that after the operator has pressed the go button the machine will automatically cycle through stages, each serving a specific purpose to produce clean instrumentation free from contamination, thermally disinfected and dry
what are the stages involved in an AWD
• Flush / pre-wash
○ This stage saturates the contaminated instrumentation
• Main wash
○ This stage is supplemented by detergent to more effectively remove contamination
• Rinse
○ This stage removes any remaining residue, biological or chemical before disinfection
• Thermal disinfection
○ This stage is actively killing micro-organisms with the use of heated water
• Drying
○ This stage removes any remaining moisture from the instruments before sterilisation
There is fresh water used for each individual stage that fills the SUMP and is then circulated throughout the chamber
when must proteins or prions (vCJD)be removed and why
This is our only opportunity to remove proteins or prion (vCJD)
They must be removed during the wash stages
They cannot be deactivated through disinfection or sterilisation
High temperature can make them adhere to the surface of instruments which makes them more difficult to remove
They can survive higher temperatures for longer periods of time than temperatures and times of standard sterilisation processes (can survive sterilisation with temperatures in excess of 150˚C for prolonged periods of time ~ 2 hours at least)
We don’t get anywhere near that temperature or period of time with a standard sterilisation cycle so they must be removed during the wash process
So the cleaning stages are the points where we remove all of the protein residue or prion that is present on the surface of the instruments
each stage of the process must be carried out at a certain temperature for a certain amount of time - what temperature should the flush / pre-wash stage be
§ Less than 35˚C
This is in relation to the coagulation of proteins ie once you breech that 35˚C mark there is the potential for proteins to begin to coagulate
what temperature should the main wash stage be
§ Temperature dependent on chemical used for process
§ When you purchase a chemical from a manufacturer it will state on the chemical itself the expected operating temperature for the chemical
§ It could be between (roughly it’s a large band) 40 and 55˚C
The engineer (competent person) would be the individual who would decide on a temperature hypothetically 45˚C and then start to operate the cycle at that point to establish how well it is removing the contamination from the surface of the instruments
what temperature should the rinse stage be
Less than 65˚C
what temperature should the thermal disinfection be and for how long
Must be between 90-95˚C for a minimum of 1minute
what temperature should the drying stage be
No specified temperature but generally between 90-110˚C
when are stage times, chemical volume and wash temperature established
• Stage times, chemical volume and wash temperature are established during the validation of the equipment by a competent person
○ When you have a machine installed the cycle must be constructed when you are on site and this will be tested by a competent person
who is a competent person
Competent person = somebody who is occupationally capable of carrying out this work to the standard that is required
what is the only stage that has no change / variance from machine to machine
The only one that has no change really, the rest of them can all be agreed at installation and validation and then they become the cycle standard, is the thermal disinfection stage as it must be between 90 and 95 degrees for a minimum hold time of 1 minute
why are washer-disinfectors the first step in the decontamination process
○ Why bother manually cleaning?
§ If you washer can remove all the contamination with an automated process, why monopolise a member of staff to do so
○ There is fresh water for each stage that not only remove contamination from the surface of the instruments but removes it from the machine entirely
○ The thermal disinfection makes the instrumentation safe for staff to handle so that a thorough inspection can take place then the instruments can be packaged for sterilisation
what happens after the WD process is finished
After the WD process is finished, all the instrumentation must be inspected for damage or to see if there is still contamination present
We use an illuminated magnifier for this
when would we incorporate manual cleaning
This is when we incorporate manual cleaning after the inspection stage if we have identified that contamination is still present
what is an advantage of physical scrubbing with a brush
Physically scrubbing something with a brush has a greater mechanical force than that of the water jets within the WD
what should be done after manual cleaning
Following manual cleaning, everything must be re-processed back through the WD because of the thermal disinfection stage
So even if we decide to manually clean something first it still must be processed through the WD because of the disinfection stage in there
That makes it safe for the operators to handle so that they can be inspected properly and any potential contamination can be identified if it is there
what happens after WD has completed its cycle and we have verified there is no contamination still present
After our WD has completed its cycle and we have verified there is no contamination still present and that the instruments are not damaged in any way, we are ready to prepare out equipment for the sterilisation process
what happens if an instrument is damaged
If the instrumentation is damaged it can either be sent
- for repair or
- For disposal at this stage
It would still have to be processed through a WD first before we identified that
