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Flashcards in Types of Disinfecting agents Deck (68)
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1
Q

What is most commonly used as part of an aseptic technique to disinfect surgical sites, injection sites, and sites with low-disinfectant requirements

A

Alcohols

2
Q

What are the advantages of alcohol?

A

Low cost
General lack of toxicity when applied topically
Bactericidal activity against gram + and gram - bacteria
Produces the largest and fastest reduction in bacterial counts

3
Q

What are the disadvantages of alcohol?

A

Ineffective against bacterial spores
Must be applied in sufficient quantities & remain in contact with the skin for 1 to 3 minutes to be effective
Flammable

4
Q

What are the most common antiseptics applied to the skin?

A

Ethyl alcohol & isopropyl alcohol 70%

5
Q

What has better virucidal activity?

A

Ethyl alcohol

6
Q

What has better bactericidal activity?

A

Isopropyl activity

7
Q

What is the mechanism of action of alcohol against pathogens?

A

Solubilizing lipid membranes and denaturing of proteins

8
Q

What viruses are largely unaffected by alcohol disinfection?

A

Nonenveloped viruses like canine parvovirus

9
Q

Why are high concentrations of alcohol less effective?

A

Very high alcohol concentrations lack the water needed to effectively denature the proteins of the pathogen

10
Q

Does alcohol have any cleaning ability?

A

No. It should not be used to cleanse the site or equipment

11
Q

What reduces the effectiveness of both ethyl and isopropyl alcohol?

A

The presence of organic debris

12
Q

Why should alcohol not be used on open wounds?

A

It denatures the structure of serum exudate and allows for the formation of a barrier that may seal in underlying bacteria, allowing the infection to spread to underlying tissues

13
Q

Why is alcohol not recommended for high-level disinfection?

A

It is not virucidal against naked viruses or bacterial spores
It is inactivated in the presence of organic debris

14
Q

Why are Halogen Chlorine Compounds classified as intermediate-level disinfectants?

A

They can kill the vegetative forms of bacteria, algae, fungi, and both enveloped & nonenveloped viruses (parvovirus)

15
Q

What is the mechanism of action of Chlorine compounds?

A

Denaturing protein structures

Chemically inactivating essential enzyme systems needed by the pathogen

16
Q

In spite of a wider spectrum of activity what are many disinfectants not effective against?

A

Bacterial spores

17
Q

What are chlorine disinfectants most commonly available as?

A

Sodium hypochlorite

18
Q

What metal is chlorine not corrosive against?

A

High-quality stainless steel

19
Q

What can generate when chlorine is mixed with other acidic cleansers?

A

Toxic amounts of chlorine gas

20
Q

What can generate when chlorine is mixed with ammonia-containing household cleansers?

A

A very poisonous gas called chloramine

21
Q

What is chlorine readily inactivated in the presence of?

A

Any organic material. It combines with organic material instead of the pathogen proteins

22
Q

What are most Iodine Compounds and Iodophors used as?

A

Topical antiseptics before surgical procedures or for aseptic disinfection of tissue

23
Q

Iodine Compounds and Iodophors are what?

A

Bactericidal, virucidal, fungicidal, and sporicidal

24
Q

What is the mechanism of action of Iodine Compounds and Iodophors?

A

Diffuses into the pathogen cell and disrupts metabolism and protein structure and synthesis

25
Q

Can iodine bring inactivated by organic material?

A

Yes, especially blood.
It is still considered to be better at maintaining its antiseptic activity in the presence of organic material than chlorines

26
Q

What are Iodine Compounds and Iodophors quite effective against?

A

Dermatophytes that cause ringworms

27
Q

What is used instead of free-iodine compounds?

A

Iodophors

Have a longer duration of antiseptic or disinfecting action

28
Q

What is an iodophor?

A

A combination of molecular iodine and a carrier molecule that releases the iodine over time
Prolonging the antimicrobial activity

29
Q

What is the most common iodophor?

A

Iodine mixed with polyvinylpyrrolidone (PVP)

A combination is more commonly known as Povidone-iodine

30
Q

When are iodophors referred to as surgical scrubs?

A

When they are combined with detergent or nonionic surfactant

31
Q

What are the surgical scrubs designed to do?

A

Clean dirty surgical sites by solubilizing dirt and organic material and providing some low-level disinfection

32
Q

Why is it important to distinguish between iodophor solutions and scrubs?

A

The presence of the scrub soap is not appropriate for any use inside of the body

33
Q

What cavity should neither iodine scrub nor solution never be used in?

A

Peritoneal cavity

34
Q

What is a member of a class of antiseptics known as biguanides and is one of the most commonly used disinfectant and antiseptic compounds in veterinary medicine?

A

Chlorhexidine

35
Q

What are the trade names of Chlorhexidine solution?

A

Nolvasan
Virosan
Hibistat

36
Q

What is the wide range of Chlorhexidine related to?

A

Its low tissue irritation and its bactericidal and fungicidal properties

37
Q

What is Chlorhexidine not considered effective against?

A

Nonenveloped viruses (parvovirus) and enveloped viruses

38
Q

What is the mechanism of action of Chlorhexidine?

A

Damaging the cell membrane of the pathogen, lysing the cell

39
Q

Is Chlorhexidine active against organic material?

A

Yes, including blood

40
Q

Is combining chlorhexidine with other cleaning products advised?

A

No. It can be inactivated by anionic and nonionic detergents, soaps, and minerals in hard water

41
Q

If Chlorhexidine is left in contact with the site, how long is its residual activity?

A

Up to 24 hours

42
Q

Can chlorhexidine be considered safe as an external ear preparation?

A

Yes, but if the compound gains access to the middle ear it is considered to be ototoxic

43
Q

What is a high-level disinfecting chemical sterilizer with a wide spectrum of activity against bacteria, viruses, fungi, and bacterial spores?

A

Glutaraldehyde

44
Q

Glutaraldehyde has a similar chemical structure to what, but has less irritation and none of the potential carcinogenic effects?

A

Formaldehyde

45
Q

Glutaraldehyde is used primarily for what?

A

A disinfectant on equipment that cannot be heat sterilized (endoscopes) and used to cold-sterilize clinical instruments

46
Q

What is an advantage of glutaraldehyde?

A

It has the ability to kill bacteria normally protected from disinfectants by biofilm

47
Q

Glutaraldehyde 2% are not inactivated by what?

A

Organic debris

Effective in the presence of hard water

48
Q

What has a significant effect on glutaraldehydes?

A

Temperature

pH

49
Q

How do oxidizing compounds work?

A

By denaturing proteins and lipids of microorganisms

50
Q

What is commonly available as a 3% solution and has historically been used to debride necrotic tissue and kill bacteria?

A

Hydrogen peroxide

51
Q

Is Hydrogen peroxide bactericidal or bacteriostatic?

A

Bactericidal

52
Q

What version of hydrogen peroxide has been successfully marketed as a proprietary compound?

A

Accelerated hydrogen peroxide

53
Q

What is the concentration of accelerated hydrogen peroxide?

A

0.5%

54
Q

What does the manufacturer of accelerated hydrogen peroxide claim?

A

That it is bactericidal, virucidal, some fungicidal activity

55
Q

What is another oxidizing agent that is used to disinfect pools, hot tubs and formulated with potassium to be used as a surface disinfectant?

A

Peroxymonosulfate

56
Q

What is mixed with a surfactant, organic acids, and buffers in a dry powder to tablet form that has to be dissolved in water?

A

Potassium peroxymonosulfate marketed as Trifectant

57
Q

Trifectant is what?

A

Virucidal (non-enveloped viruses), bactericidal, fungicidal

58
Q

What is part of a larger group of related compounds in mouthwashes, surface disinfectants, and many household disinfectants (Lysol, pine oil, similar cleansers)

A

Phenols

59
Q

What are phenol compounds quite effective against?

A

Gram + bacteria

60
Q

What are phenol compounds quite ineffective against?

A

Gram-negative bacteria
Viruses
Fungi
Spores

61
Q

Are phenols easily inactivated by organic material?

A

No

62
Q

What are Quaternary Ammonium Compounds?

A

Cleansing agents with germicidal activity

63
Q

What are quaternary ammonium compoinds used to disinfect?

A

surfaces of floors, walls, and vehicles used in livestock and egg-laying operations

64
Q

Why are quaternary ammonium compoinds not used as antiseptics?

A

because the active ingredients bind to gauze & cotton

65
Q

What is the major quaternary ammonium compound used in vet med?

A

Benzalkonium chloride which is the key ingredient in Roccal-D

66
Q

What are quaternary ammonium compounds effective against?

A

Gram + bacteria

Enveloped viruses

67
Q

What are quaternary ammonium compounds ineffective against?

A

Bacterial spores
Non-enveloped viruses
Poor efficacy against fungi & gram-negative bacteria

68
Q

What is used together to irrigate ear infections, wounds, or fistulas with Pseudomonas and are considered effective against a fairly narrow spectrum of gram - bacteria and Staphylococcus aureus?

A

Ethylenediamine tetraacetic acid (EDTA) and Tris buffer compounded