Types of Disinfecting agents

Question 1

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

Answer 1

Alcohols

Question 2

What are the advantages of alcohol?

Answer 2

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

Question 3

What are the disadvantages of alcohol?

Answer 3

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

Question 4

What are the most common antiseptics applied to the skin?

Answer 4

Ethyl alcohol & isopropyl alcohol 70%

Question 5

What has better virucidal activity?

Answer 5

Ethyl alcohol

Question 6

What has better bactericidal activity?

Answer 6

Isopropyl activity

Question 7

What is the mechanism of action of alcohol against pathogens?

Answer 7

Solubilizing lipid membranes and denaturing of proteins

Question 8

What viruses are largely unaffected by alcohol disinfection?

Answer 8

Nonenveloped viruses like canine parvovirus

Question 9

Why are high concentrations of alcohol less effective?

Answer 9

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

Question 10

Does alcohol have any cleaning ability?

Answer 10

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

Question 11

What reduces the effectiveness of both ethyl and isopropyl alcohol?

Answer 11

The presence of organic debris

Question 12

Why should alcohol not be used on open wounds?

Answer 12

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

Question 13

Why is alcohol not recommended for high-level disinfection?

Answer 13

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

Question 14

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

Answer 14

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

Question 15

What is the mechanism of action of Chlorine compounds?

Answer 15

Denaturing protein structures

Chemically inactivating essential enzyme systems needed by the pathogen

Question 16

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

Answer 16

Bacterial spores

Question 17

What are chlorine disinfectants most commonly available as?

Answer 17

Sodium hypochlorite

Question 18

What metal is chlorine not corrosive against?

Answer 18

High-quality stainless steel

Question 19

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

Answer 19

Toxic amounts of chlorine gas

Question 20

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

Answer 20

A very poisonous gas called chloramine

Question 21

What is chlorine readily inactivated in the presence of?

Answer 21

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

Question 22

What are most Iodine Compounds and Iodophors used as?

Answer 22

Topical antiseptics before surgical procedures or for aseptic disinfection of tissue

Question 23

Iodine Compounds and Iodophors are what?

Answer 23

Bactericidal, virucidal, fungicidal, and sporicidal

Question 24

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

Answer 24

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

Question 25

Can iodine bring inactivated by organic material?

Answer 25

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

Question 26

What are Iodine Compounds and Iodophors quite effective against?

Answer 26

Dermatophytes that cause ringworms

Question 27

What is used instead of free-iodine compounds?

Answer 27

Iodophors | Have a longer duration of antiseptic or disinfecting action

Question 28

What is an iodophor?

Answer 28

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

Question 29

What is the most common iodophor?

Answer 29

Iodine mixed with polyvinylpyrrolidone (PVP) | A combination is more commonly known as Povidone-iodine

Question 30

When are iodophors referred to as surgical scrubs?

Answer 30

When they are combined with detergent or nonionic surfactant

Question 31

What are the surgical scrubs designed to do?

Answer 31

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

Question 32

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

Answer 32

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

Question 33

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

Answer 33

Peritoneal cavity

Question 34

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?

Answer 34

Chlorhexidine

Question 35

What are the trade names of Chlorhexidine solution?

Answer 35

Nolvasan Virosan Hibistat

Question 36

What is the wide range of Chlorhexidine related to?

Answer 36

Its low tissue irritation and its bactericidal and fungicidal properties

Question 37

What is Chlorhexidine not considered effective against?

Answer 37

Nonenveloped viruses (parvovirus) and enveloped viruses

Question 38

What is the mechanism of action of Chlorhexidine?

Answer 38

Damaging the cell membrane of the pathogen, lysing the cell

Question 39

Is Chlorhexidine active against organic material?

Answer 39

Yes, including blood

Question 40

Is combining chlorhexidine with other cleaning products advised?

Answer 40

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

Question 41

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

Answer 41

Up to 24 hours

Question 42

Can chlorhexidine be considered safe as an external ear preparation?

Answer 42

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

Question 43

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

Answer 43

Glutaraldehyde

Question 44

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

Answer 44

Formaldehyde

Question 45

Glutaraldehyde is used primarily for what?

Answer 45

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

Question 46

What is an advantage of glutaraldehyde?

Answer 46

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

Question 47

Glutaraldehyde 2% are not inactivated by what?

Answer 47

Organic debris | Effective in the presence of hard water

Question 48

What has a significant effect on glutaraldehydes?

Answer 48

Temperature | pH

Question 49

How do oxidizing compounds work?

Answer 49

By denaturing proteins and lipids of microorganisms

Question 50

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

Answer 50

Hydrogen peroxide

Question 51

Is Hydrogen peroxide bactericidal or bacteriostatic?

Answer 51

Bactericidal

Question 52

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

Answer 52

Accelerated hydrogen peroxide

Question 53

What is the concentration of accelerated hydrogen peroxide?

Answer 53

0.5%

Question 54

What does the manufacturer of accelerated hydrogen peroxide claim?

Answer 54

That it is bactericidal, virucidal, some fungicidal activity

Question 55

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

Answer 55

Peroxymonosulfate

Question 56

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

Answer 56

Potassium peroxymonosulfate marketed as Trifectant

Question 57

Trifectant is what?

Answer 57

Virucidal (non-enveloped viruses), bactericidal, fungicidal

Question 58

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

Answer 58

Phenols

Question 59

What are phenol compounds quite effective against?

Answer 59

Gram + bacteria

Question 60

What are phenol compounds quite ineffective against?

Answer 60

Gram-negative bacteria Viruses Fungi Spores

Question 61

Are phenols easily inactivated by organic material?

Answer 61

No

Question 62

What are Quaternary Ammonium Compounds?

Answer 62

Cleansing agents with germicidal activity

Question 63

What are quaternary ammonium compoinds used to disinfect?

Answer 63

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

Question 64

Why are quaternary ammonium compoinds not used as antiseptics?

Answer 64

because the active ingredients bind to gauze & cotton

Question 65

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

Answer 65

Benzalkonium chloride which is the key ingredient in Roccal-D

Question 66

What are quaternary ammonium compounds effective against?

Answer 66

Gram + bacteria | Enveloped viruses

Question 67

What are quaternary ammonium compounds ineffective against?

Answer 67

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

Question 68

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?

Answer 68

Ethylenediamine tetraacetic acid (EDTA) and Tris buffer compounded