Antiseptics and Disinfectants

Question 1

define disinfectant

Answer 1

a chemical applied to inanimate objects to kill or inhibit further growth of microorganisms. What they kill depends on the product

Question 2

what is an antiseptic?

Answer 2

similar to disinfectant but can be used on living tissues (e.g. patient preparation)

Question 3

define detergent

Answer 3

solutions with cleaning activity, usually used to remove organic material that could affect the efficacy of disinfectants

Question 4

define sterilisation

Answer 4

when a product is freed of all microorganisms

Question 5

define asepsis

Answer 5

removal of all microorganisms and spores usually removed through sterilisation

Question 6

define disinfection

Answer 6

removal of microorganisms

Question 7

what two states do bacteria exist as?

Answer 7

spores and vegetative

Question 8

what are vegetative bacteria?

Answer 8

bacteria that are living and replicating

Question 9

what are spores?

Answer 9

dormant bacteria resistant to lots of chemicals

Question 10

how are gram + and gram - bacteria differentiated?

Answer 10

how they stain

Question 11

How may bacteria present?

Answer 11

rods, cocci. In singles, pairs or a cluster

Question 12

give an example of 2 gram positive bacteria

Answer 12

staphylococcus and bacillus

Question 13

give 2 examples of gram negative bacteria

Answer 13

E coli, Pseudomonas

Question 14

what are the 2 types of viruses?

Answer 14

enveloped and non enveloped

Question 15

describe enveloped viruses

Answer 15

surrounded by a lipid layer which makes them easier for disinfectants to break down

Question 16

describe non-enveloped viruses

Answer 16

much more resistant to chemicals as outer layer is not lipid based

Question 17

give 2 examples of enveloped viruses

Answer 17

canine distemper and feline immunodeficiency virus

Question 18

give examples of non-enveloped viruses

Answer 18

parvovirus and feline calicivirus (khalisi)

Question 19

what are protozoa?

Answer 19

single celled organisms

Question 20

what are prions?

Answer 20

folded proteins

Question 21

describe the ideal disinfectant

Answer 21

broad spectrum but particularly effective against HAI’s
non-irritant and non-toxic
easy to use on inanimate objects without causing corrosion or stains
stable and not easily inactivated
cost effective
rapid mode of action
remains on the surface for full contact time
not deactivated by organic matter or detergents

Question 22

what factors should be considered when choosing a disinfectant or antiseptic?

Answer 22

what will it be used for (living tissue/inanimate objects)
degree of organic matter present
contact time (and time available to you - e.g. not extending anesthetic unnecessarily
is it being used for regularly encountered bacteria or isolation cases

Question 23

what are the 6 types of disinfectants/antiseptics

Answer 23

alcohols
aldehydes
biguanides
halogens
QAC's
phenols

Question 24

How do alcohols work?

Answer 24

cause cell membrane damage

Question 25

how fast does alcohol act?

Answer 25

fast

Question 26

is there any residual activity of alcohol?

Answer 26

no - evaporates quickly

Question 27

what is alcohol effective against?

Answer 27

broad spectrum but not non enveloped viruses or spores

Question 28

what is the clinical use of alcohol?

Answer 28

hand disinfection | patient prep

Question 29

how do aldehydes work?

Answer 29

denature proteins

Question 30

what are two types of aldehydes?

Answer 30

formaldehyde and gluteraldehyde

Question 31

why are aldehydes not often used?

Answer 31

they are carcinogenic

Question 32

what are aldehydes effective against?

Answer 32

broad spectrum including non enveloped viruses and spores

Question 33

what are aldehydes not used for due to their toxicity?

Answer 33

cleaning

Question 34

what are aldehydes used for?

Answer 34

sample preservation

Question 35

how do biguanides work?

Answer 35

alter permeability of cell membrane

Question 36

what is the problem with biguanides?

Answer 36

inactivated by organic material

Question 37

do biguanides have good residual action?

Answer 37

yes

Question 38

what are biguanides effective against?

Answer 38

gram + and some gram - bacteria, limited fungi

Question 39

what are biguanides not effective against?

Answer 39

spores or mycobacteria

Question 40

what is the clinical use of biguanides?

Answer 40

patient prep and surgical scrub

Question 41

give an example of a biguanide

Answer 41

chlorhexidine (hibiscrub)

Question 42

What are halogens?

Answer 42

chlorine and iodophors

Question 43

what are halogens effective against?

Answer 43

broad spectrum including unenveloped viruses

Question 44

what are halogens used for?

Answer 44

chlorine - cleaning (bleach) | iodophors - skin disinfectant

Question 45

what does QAC stand for?

Answer 45

Quaternary ammonium compounds

Question 46

what effect do QACs have?

Answer 46

inactivate enzymes, denature proteins

Question 47

what is the residual activity of QACs?

Answer 47

some

Question 48

what are QACs effective against?

Answer 48

broad spectrum but not effective against unenveloped viruses, mycobacteria and spores

Question 49

what are QACs used for?

Answer 49

surface disinfectant

Question 50

what is the effect of phenols?

Answer 50

denature proteins and disrupt cell membranes

Question 51

what is an issue with phenols?

Answer 51

toxic at certain concentrations and toxic at all times for cats

Question 52

what are phenols effective against?

Answer 52

broad spectrum but no unenveloped viruses or spores

Question 53

what are phenols used for?

Answer 53

surface disinfectants

Question 54

what is most important when using disinfectants?

Answer 54

read the labels to ensure correct disinfectant and concentration are used for the circumstances