Antiseptics and disinfectants

Question 1

what are the levels of microbial control from lowest to highest?

Answer 1

cleaning, sanitation, antiseptic, disinfection, sterilization

Question 2

antiseptics

Answer 2

iodine, chlorohexidine, hydrogen peroxide, alcohols, phenols

Question 3

iodine antiseptics

Answer 3

effective but limited activity against bacterial spores
used for surgical preparation, topical wound therapy, joint and cavity lavage
used for eyes

Question 4

tinctures of iodine

Answer 4

2% solution in 50% ethyl alcohol
used on intact skin, not used un vet

Question 5

idophors

Answer 5

contain iodine complexed with surfactants or polymers so free iodine is slowly released
staining and irritation reduced while the tissue delivery is enhanced

Question 6

povidine-iodine

Answer 6

most common in vet
has higher levels of free iodine and has greater bactericidal activity but are also cytotoxic
must be diluted
dilution decreases cytotoxicity and decreases bactericidal activity
residual activity: 4-6 hours but may be diminished in the presence of organic matter
can cause irritation and acute dermatitis in 50% of dogs
systemic iodine toxicity may cause thyroid dysfunction and metabolic acidosis

Question 7

chlorohexidine

Answer 7

effective against bacteria, molds, yeast, and viruses
rapid onset and long residual activity
nonirritating to the skin
available in aqueous solutions, tinctures, and detergent formulations (scrubs)
dilute solution 1:40 with sterile water or saline, produces 0.05% solution
dilution has superior antibacterial activity and no cytotoxicity
will precipitate with electrolyte solutions
scrub used for surgical prep, solution used for lavage, rinsing or soaking

Question 8

hydrogen peroxide

Answer 8

H2O2
potent antiseptic , disinfectant, and sterilant
kills microorganisms via oxidation
common concentration 3% solution
light sensitive
turns into water when exposed to room air (loses extra oxygen molecule)
very irritating and can be cytotoxic to skin
may delay healing and kill healthy healing cells
not recommended for cleaning incision sites or blood stains on tissue

Question 9

alcohols antiseptics

Answer 9

organic solvents that evaporate rapidly and leave no residue
may be used as antiseptics or disinfectants
bactericidal but ineffective against spores
no residual activity and are inhibited by organic debris
ethyl and isopropyl more effective than methyl as disinfectants
should never be used in open wounds, body cavities or mm
cytotoxic and painful

Question 10

phenols

Answer 10

carbolic acid
was used as an antiseptic or disinfectant
replaced by newer, safer, more effective agents
Hexachlorophene (skin prep) was popular phenol replaced by povidone-iodine and cholorhexidine

Question 11

quaternary ammonium

Answer 11

disinfectant
synthetic cationic detergents that act on cell membranes and are effective against bacteria, some viruses, but not spores
nontoxic
inactivated by organic material, soap, hard water
don’t mix with bleach or other disinfectants= lethal vapors

Question 12

what is the most common quaternary ammonium disinfectant?

Answer 12

Benzalkonium chloride

Question 13

phenol class disinfectants

Answer 13

phenols, carbolic acid, coal tar, cresol, Hexachlorophene, pine oil
good against bacteria
limited against viruses and fungi
not sporicidal
toxic to cats, rodents, and rabbits
not inactivated by organic material, soaps, or hard water
brand name: Pine Sol

Question 14

aldehyde class disinfectants

Answer 14

toxic and irritating
not used on living tissues
can sterilize with enough contact time (sporicidal at >12 hours contact time)

Question 15

formaldehyde

Answer 15

carcinogenic and very irritating to skin and respiratory tract

Question 16

glutaraldehyde (Cidex), orthro-phtaladehyde

Answer 16

aldehyde class
cold sterile and less toxic than formaldehyde
dulls sharp edges with time
inactivated by organic material
used for minor surface surgeries (dental equipment, endoscopes)

Question 17

Cidex

Answer 17

common brand name of cold sterile solutions
lasts either 14 days or 28 days after reconstituting with activating powder
has a high level of disinfection

Question 18

disinfect chloride

Answer 18

one of the 1st agents used as medical disinfectants
hypochlorites have been broad bactericidal, virucidal, and fungicidal activity
can be cytotoxic
bleach is commonly used as a disinfectant
dilution: 1:32 for general disinfection, 1:10 for ringworm
don’t mix with ammonia
can be used as an antiseptic (not common)