LDU

Question 1

List reasons for cleaning (3)

Answer 1

1. Medicolegal requirement
2. Remove biological matter - functionality
3. Minimise cross contamination

Question 2

Features of a decon box (5)

Answer 2

1. Tight fitting lid
2. Leakproof
3. Durable
4. Rigid sided
5. Colour coded

Question 3

Describe steps of LDU (8)

Answer 3

1. Hand hygiene + PPE
2. Dispose of disposable/reusable items into transport box
3. Set dirty instruments in to dirty instrument area
4. AWD daily checks + loading
5. AWD cycle
6. Inspection - reprocess if dirty
7. Manually clean + US (OLD NOTES)
8. Steriliser
9. Position in clean instrument cool down area then clean box

Question 4

List daily checks for AWD

Answer 4

Check spray arms/jets free from blockage
Check door seal
Check filter
Check chemical level
Check load carrier

Question 5

AWD loading requirements

Answer 5

Utilise basket furniture
No overlapping/shadowing
Hinged instruments open at hinge
Assemblies dissembled

Question 6

Describe the AWD cycle (5)

Answer 6

1. Flush - remove easy debris (30-35)
2. Wash - remove hard debris (biological matter)
3. Rinse - remove detergent/cleaner (<65)
4. Disinfection - 90-95 degrees for 1 min
5. Dry - hot air in chamber to remove excess moisture (90-110)

Question 7

What to check under inspection?

Answer 7

Illuminated magnifier to check for residual contamination, functionality of instruments, damage/corrosion

Question 8

Requirements of manual cleaning

Answer 8

PPE (apron, visor, rubber gloves, heavy duty gloves)
Dedicated cleaning sink
Water <35 + chemical detergent (enzymatic or pH neutral)
Long handled soft bristle brush scrub below water to decrease spread of contaminants
Use overflow plug in

Question 9

What are the 2 methods for manual cleaning

Answer 9

Immersion
Non immersion - handpieces

Question 10

What are the issues with manual cleaning (4)

Answer 10

1. Splashing
2. Cross contamination
3. Sharps injuries
4. Human error

Question 11

Ultrasonic loading requirements

Answer 11

Utilise basket furniture
No overlapping/shadowing
Hinged instruments open at hinge
Assemblies disassembled

Question 12

Ultrasonic checks

Answer 12

Degas to remove o2 - o2 inhibits cavitation
Check chemical level

Question 13

What has to be done after use of US?

Answer 13

Rinse in separate sink
Reprocess through AWD disinfection
Change PPE between
Inspection
Sterilisation

Question 14

Why do we lubricate joints/hinges before sterilisation?

Answer 14

Prevent corrosion

Question 15

Temp + pressure gauge for sterilisation

Answer 15

134-137
2.05-2.35 pressure gauge
3.05-3.35 pressure absolute

Question 16

Type B steriliser

Answer 16

B for better
Vacuum capable - active air removal
Channeled, wrapped, lumened, porous, cannulated instruments

Question 17

Type B steriliser disadvantages

Answer 17

Additional periodic testing required

Question 18

Type N steriliser

Answer 18

Non vacuum - gravity displacement - passive air removal
No wrapped, channeled, lumened instruments only rigid

Question 19

Backup cleaning method if AWD is not available

Answer 19

Ultrasonic

Question 20

Why do we not let instruments air dry

Answer 20

Trapped moisture –> corrosion/microbial growth

Question 21

What type of water do we use

Answer 21

Sterile or reverse osmosis

Question 22

How do you clean handpieces

Answer 22

AWD + Type B steriliser
Can’t go in US
Cant go in Type N steriliser
only non immersion manual wash

Question 23

What are the conditions for storing instruments?

Answer 23

Clean, dry, organised

Question 24

What is the protocol for dirty instruments with contamination stuck on it

Answer 24

US - indication for stubborn contamination

Question 25

What are indications for manual wash?

Answer 25

AWD failure/servicing

Question 26

AWD weekly tests

Answer 26

Cleaning efficacy test
- Test for residual protein detection on instruments

ACT
- Ensures AWD continues to function correctly
- Check temp/time within disinfection range, door cant be opened during cycle time

Question 27

AWD daily checks

Answer 27

Door seal for damage
Load carrier for damage
Chamber for debris
Fill + drain water daily

Sprays arms/jets free from blockage
Check filter
Check door seal
Check chemical level
Check load carrier
Cleaning efficacy test visually (daily)

Question 28

US daily checks

Answer 28

Door seal for damage
Load carrier for damage
Chamber for debris
Fill + drain water daily
Cleaning efficacy test visually (daily)

Question 29

US weekly checks

Answer 29

Cleaning efficacy test
- ability to remove test soil from instruments

ACT

Test for US activity
- Erosive pattern created on aluminium foil exposed in bath

Question 30

Steriliser daily checks

Answer 30

Door seal for damage
Load carrier for damage
Chamber for debris
Fill + drain water daily

Question 31

Steriliser weekly checks

Answer 31

ACT
- Run load and check printout ensure parameters within range (temp, pressure,hold time)

Question 32

Daily type B steriliser tests

Answer 32

Steam Penetration (Bowie dick/Helix)
- Measures reach of pressure + temp for adequate sterilisation
- Shows steam penetrates rapidly + evenly
- 100% colour change required

Question 33

Weekly type B steriliser tests

Answer 33

ACT
- Check air not leaking into steriliser
- Can impair steam penetration, prevent sterilisation, recontaminate damp load during drying phase

ADSFT
- Fitted to detect residual air that will prevent sterilisation