Decontamination textbook

Question 1

What are the 6 parts in the chain of infection?

Answer 1

1. Infectious agent
2. Reservoir
3. portal of exit
4. means of transmission
5. portal of entry
6. suceptible host.

Question 2

what is the R₀ number?

Answer 2

the number of cases one case generates on average over the course of its infective period.

Question 3

what does an R₀ <1 mean?

Answer 3

the infection will die out in the long run.

Question 4

what does an R₀ >1 mean?

Answer 4

the infection will be able to spread in a population.

Question 5

compare small and large droplets in terms of their transmission ability.

Answer 5

Large droplets are good for infecting surfaces.

Small droplets can evaporate into the air where they can stay for minutes or hours.

Question 6

discuss influenza action

Answer 6

influenza has 2 surface glycoproteins:

Hemaglutinin H1-15 which is a key component for interaction with the cell.

Neuroaminidase N1-9 which the virus uses to break out of infected cells.

Question 7

What is Spaulding?.

Answer 7

This is used to describe the risk of infection:
Critical

Semi-critical

Non-critical

Minimal risk.

Question 8

Discuss the relevance of COI pseudomonas aeruginosa?

Answer 8

It is a gram negative bacilli.

It can be found in contaminated water so can contaminate the dental system getting into the hand-piece and infecting aerosols.

Question 9

What PPE do we use during disinfection?

Answer 9

Apron- to prevent ourselves from being contaminated

Gloves- to protect our hands

Visor- to protect our face and eyes

Question 10

List the stages of disinfection?

Answer 10

Transport

Washer disinfector

Inspection

Packaging

Sterilisation

Storage.

Question 11

What are the stages of the automatic washer disinfector?

Answer 11

Prewash - Saturates contaminated instruments

Main wash- Use detergents to effectively remove contamination

Rinse - Removes any remaining residue

Thermal disinfection- Uses heated water (90-95*) to kill the micro-organisms.

Drying- Removes any remaining moisture before sterilisation

Question 12

How is contamination removed from the washer disinfector?

Question 13

What do we use to inspect instruments and what are we looking for?

Answer 13

An illuminated magnifier

Looking for contamination and damage.

Question 14

After inspection we have noticed an instrument is contaminated. How do we proceed?

Answer 14

We put clean the instrument through manual cleaning or ultrasonic before putting it through the AWD again.

Question 15

Describe manual washing?

Answer 15

This requires 3 sinks (washing/rinsing/handwashing)

You need to wash under the water to contact water and disinfectant & prevent aerosol production.

Question 16

When do we use manually scrubbing?

Answer 16

When the instrument can only be cleaned manually.

Question 17

How does an ultrasonic work to clean instruments?

Answer 17

High frequency sound waves produce bubbles that expand and collapse scouring the hard surface

Question 18

Why do we use steam to sterilise the instruments?

Answer 18

It is non toxic

Produces no waste except water

Carries alot of energy.

Question 19

How does a type N steriliser work and what is it used for?

Answer 19

The steam forces the gas out.

It is used for rigid steel instruments with no pocket channels or lumen.

Question 20

How does a type B steriliser work and what is it used for?

Answer 20

It removes the air from the chamber creating a vacuum and then fills the chamber with steam.

Question 21

Which steriliser do we commonly use

Answer 21

Type B steriliser

Question 22

What is the stage time and temperature recognised to achieve sterilisation.

Answer 22

3 minutes and 134-137 degrees Celsius

Question 23

What are the 4 key elements for successful cleaning?

Answer 23

Energy, chemical, temperature, time.

Question 24

Why do we limit the time between use and processing?

Answer 24

So that the blood or biological matter does not have time to dry in and adhere to the instrument.

Question 25

What chemical is used in the washerdisinfectant?

Answer 25

High and low alkaline detergent

Question 26

What chemical is used in the ultrasonic?

Answer 26

Enzymatic detergent

Question 27

What chemical do we use in manual washing?

Answer 27

Ph neutral detergent

Question 28

Compare the force used for cleaning of the manual, ultrasonic and washer disinfector.

Answer 28

Manual

Question 29

At what temperature does manual cleaning occur ?

Answer 29

\<35 degrees celsius

Question 30

At what temperature and for how long does the ultrasonic work?

Answer 30

\<35 degrees for 20 minutes

Question 31

At what temperature and for how long does the washer disinfector work?

Answer 31

\<65 degrees for 55 minutes

Question 32

At what temperature and for how long does thermal disinfection occur.

Answer 32

between 90 and 95 degrees for a minimum of 1 minute.

Question 33

At what pressure does steam sterilisation occur?

Answer 33

2-2.3 bar pressure

Question 34

What type of water is used for sterilisation and why?

Answer 34

Purified water (so that there is a reduced conductivity and low levels of bacteria and fungals)

Question 35

What container must be used when transporting used instruments?

Answer 35

Durable/leak proof container. With a tight fitting lid Can be easily cleaned and disinfected.

Question 36

Compare guidance, legislation and standards in terms of decontamination

Answer 36

Guidance- documents directing peple about working in decontamination Legislation- must be complied with. Standards- provide details on how to carry out certain tasks

Question 37

In terms of decontamination who is the user?

Answer 37

The person responsible for the sterilizer/washer disinfectant.

Question 38

What is a medical device?

Answer 38

Any instrument used for procedures and the equipment used to reprocess the instrument.

Question 39

Why do we test equipment?