Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

OD2 (S1&2) > MIIM - Sterilisation, Disinfection, and Infection Control - Week 8 > Flashcards

MIIM - Sterilisation, Disinfection, and Infection Control - Week 8 Flashcards

1
Q

Define aseptic technique.

A

Using procedures that minimise the transfer of micro-organisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define infection control.

A

Involves the prevention or minimisation of cross infections.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define cross infection (3).

A

The spread of micro-organisms from patient to staff, staff to patient, and patient to patient.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

List 5 risk factors for spreading infection in an optometric setting.

A

Removing foreign bodies
Assessing patients with ocular trauma or infection
Carrying out lacrimal lavage
Expressing glands and cysts
Fitting contact lenses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Briefly mention some diseases that can be passed from patient to optometrist (13).

A

HIV
Hepatitis B and C
Measles
Mumps
Rubella
Varicella
Glandular fever
Herpes
Influenza
Adenovirus 8
CJD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define cleaning.

A

Removal of contaminating matter to lower the burden of organic material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define disinfection.

A

Removing from an article some or all of its pathogenic micro-organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define sterilisation.

A

Destruction or removal of all viable micro-organisms, spores, and other infectious agents from an article

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define and describe the three categories of the spaulding classification system.

A

Critical - invasive devices that enter normally sterile tissue or the vascular system by intent or accident
Semi-critical - device contacts, but does not penetrate, mucous membranes
Non-critical - device only contacts skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe how to determine the initial contamination level of a sample.

A

Serially dilute the sample, spread on agar plates, incubate, and count colonies.
One colony represents one microbial cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe how to determine the rate of biocidal action on a given pathogen.

A

Determine initial viable count
Expose to the agent
Repeat viable counts
Calculate the decimal reduction time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define decimal reduction time.

A

Time to reduce a population 10-fold at a particular temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define sterility assurance.

A

The probability that a micro-organism could survive a sterilisation process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the relationship between the D-value and sterility assurance?

A

Descreasing linear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Define what is meant by biocidal. Is it reversible or irreversible?

A

Processes or agents that kill micro-organisms and are irreversible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define what is meant by biostatic. Is it reversible or irreversible?

A

Processes or agents which inhibit microbial growth but are usually reversible.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name 4 main methods used for sterilisation.

A

Heat
Filtration
Ionising radiation
Chemical agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Differentiate between the effects of moist vs dry heat.

A

Moist heat coagulates
Dry heat oxidises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is more effective, moist or dry heat? Describe why.

A

Moist heat is more effective.
When steam condenses, it liberates intense latent heat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When would dry heat be used for sterilisation (6)?

A

Glass, metal, cutting instruments, powders, waxes, eye ointment bases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When would moist heat be used for sterilisation (2)?

A

Most non-heat sensitive instruments, decontamination of used articles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Name 4 advantages of dry heat.

A

Penetrates solids, usable on non-aqueous liquids, closed cavities, non-corrosive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Name 2 advantages of moist heat.

A

Rapid and effective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Name 3 disadvantages of dry heat.

A

Long times
Very high temperatures
Potentially very destructive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Name 2 disadvantages of moist heat.

A

Corrosive over time
Wets articles like wrappings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Briefly describe how an autoclave works.

A

Its like a pressure cooker.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Does filtration kill micro-organisms?

A

No, just removes them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

By what two processes does filtration work?

A

A combination of adherence and exclusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

When are filters used?

A

For heat-sensitive liquids and air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Describe the structure of depth filters and what they are made of (3). Do they have good flow?

A

Maze-like fibrous sheet or mat
Can be made of paper, asbestos, or glass fibles
Has good flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Describe the structure of membrane filters and what they are made of (2). Do they have good flow?

A

Large number of tiny holes like a sieve
Made of cellulose acetate or nitrate
Has good flow

32
Q

Describe the structure of nucleation track filters and what they are made of. Do they have good flow?

A

Has a small number of holes like a mat
Made of very thin polycarbonate film, which is irradiated then etched
Has low flow rate

33
Q

How does ionising radiation sterilise?

A

By creating free radicals which damage DNA

34
Q

Name three advantages of using ionising radiation to sterilise.

A

Effective at ambient temperature
No wetting
Articles packaged ready for use

35
Q

Name three disadvantages of using ionising radiation to sterilise.

A

High installation costs
Safety issues
Possible deleterious effects

36
Q

Give two examples of sterilising chemicals.
Give an advantage and four disadvantages of these.

A

Gluteraldehyde and ethylene oxide
Advantage - broad spectrum
Disadvantage - slow, expensive, toxic residues, carcinogenic

37
Q

Name three kinds of indicators for monitoring the effectiveness of sterilisation.

A

Physical
Chemical
Biological

38
Q

Describe an example of a physical indicator for an autoclave.

A

A printer that contains the date, temperature, and time of sterilisation.

39
Q

Describe an example of a chemical indicator for an autoclave.

A

An autoclave tape which changes colour at a given temperature

40
Q

Describe an example of a biological indicator for an autoclave.

A

Spore strips which are placed into the autoclave as well and checked for viability

41
Q

Briefly describe the hazard analysis critical control points process.

A

A way to make a process more effective by identifying certain critical points in the process and monitoring them

42
Q

Name three disinfection methods.

A

Simple washing and cleaning
Hot water/steam for shorter times
Chemical disinfectants

43
Q

What is the aim of handwashing?

A

To remove transient flora

44
Q

Does handwashing eliminate resident flora?

A

No, it can only be reduced

45
Q

When should hands be washed (2)?

A

Before and after seeing a patient.

46
Q

Name 5 properties that an ideal handwash should have.

A

Broad spectrum
Non-irritant
Non-allergenic
Rapid action
Residual action

47
Q

What kinds of micro-organisms are the most susceptible to disinfectants (2)?

A

Vegetative bacteria
Enveloped viruses (influenza/HIV)

48
Q

What kinds of micro-organisms are moderately susceptible to disinfectants (2)?

A

Acid-fast bacteria
Non-enveloped viruses

49
Q

What kinds of micro-organisms are the least susceptible to disinfectants (4)?

A

Fungal and bacterial spores
Protozoal cysts
Prions

50
Q

Name two disinfectants with a broad spectrum.

A

Aldehydes and halogens

51
Q

Give three examples of disinfecting agents with a limited spectra.

A

Alcohols
Phenols
Chlorhexidine

52
Q

Name 5 factors that affect the efficiency of a disinfectant.

A

Concentration
Contact time
Temperature
pH
Presence of organic material

53
Q

Name a disinfectant that is effective in all situations.

A

None

54
Q

What is essential to disinfecting?

A

Thorough pre-cleaning

55
Q

Give an example of a halogen disinfectant and whether or not it leaves a toxic residue.

A

Hypochlorous acid
Non-toxic residue

56
Q

What concentration are halogens used to clean tonometers and gonio prisms?

A

0.4-0.5%

57
Q

What is an alternative to chlorhexidine when broader spectrum is needed? Explain briefly how it works.

A

Iodophors
Iodine is trapped in micelles and dispersed in a liquid colloid

58
Q

What is a disadvantage of iodophors?

A

Can cause contact dermatitis

59
Q

what concentration of hydrogen peroxide should be used to clean tonometers and gonio prisms?

A

3%

60
Q

Do alcohol water mixtures leave residual activity after evaporating?

A

No

61
Q

Are alcohol water mixtures effective against spores and cysts?

A

No

62
Q

What can prolonged exposure to alcohol water mixtures cause?

A

Drying

63
Q

What percentage of alcohol should be used for cleaning tonometers and gonio prisms?

A

70-80%

64
Q

What should be used on dirty surfaces?

A

Phenols

65
Q

What disinfectant is unaffected by organic material?

A

Phenols

66
Q

What is essential when using phenols?

A

Accurate dilution

67
Q

Are phenols effective against spores and non-enveloped viruses?

A

No

68
Q

What is chlorhexidine less effective against, gram positive or negative?

A

Negative

69
Q

Is chlorhexidine effective against spores and non-enveloped viruses?

A

No

70
Q

Does chlorhexidine leave residual or cumulative action?

A

Both

71
Q

Is chlorhexidine non-toxic?

A

Yes

72
Q

Is chlorhexidine non-irritant and non-allergenic?

A

Yes

73
Q

What two things affect the activity of chlorhexidine?

A

Anions and soaps

74
Q

What disinfecting agent is useful for gram-positive bacteria and non-enveloped viruses?

A

Quaternary ammonium compounds

75
Q

What are quaternary ammonium compounds easily inactivated by?

A

Organic matter

OD2 (S1&2) (174 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions