Protazoa

Fungi

Bacteria

Not a major surgical concern

post surgical contamination via licking

post surgical asepsis required

check and clean daily w diluted chlorhex or peroxide

cause skin dz under normal conditions

improper cleaning of ET tubes, instruments lead to internal organ contamination

major concern when cleaning and sterilizing

if animals living quarters contaminated

many are opportunistic

Most surgical and post surgical probs from:

improper care & cleaning of

equip,

suites,

recovery,

surg site prep,

personnel

eliminate or control the source

increase ability of host to resist dz

prevent transmission of microbes

diet

therapeutic agents

hygiene

vitamins

vx

To prevent transmission of microbes:

wash hands

adequate ventilation (very important)

physical & chemical control

Physical methods of microbe control:

dry heat

moist heat

radiation

drying, ie the dryer

incineration

hot air ovens

does not sterilize

bacteriostatic

removal of water inhibits microbe growth

soiled garments washed & dried ASAP, 

towels & blankets replaced & cleaned/dried if moist or dirty

as moisture evaporates waste will drop off fabric & be dispersed by air current

complete destruction of material

only on non-reusable or no-value items

must be completely reduced to ashes

partially burned lumps may contain/protect microbes

for sterilization

economical

does not dull sharp edges

no metal corrosion

oils, gels & waxes in small amts

powdery stuff (vxs)

takes a long time

paper & cloth usually scorched

plastic & rubber adversely affected

temp: 150-170 F for 1-3 hrs depending on material 

not used much anymore

FYI

hot water

boiling

free flowing steam

steam under pressure

sanitize, not sterilize

temp 140F (60C) or higher

agitation or scubbing increases sanitizing along w added detergents

Boiling to control microbes:

disinfects

max temp reached 212F (100C) for 1 hr

not effective d/t resistance of spores & viruses

emergency substitute to try to attain asepsis

212 F for 30-45 mins

same prob as boiling

can fractionally sterilize some fluids

large scale use to clean SS cages, effectively disinfects

AUTOCLAVE!

** When pressure increased, temp of steam increased

same principle as pressure cooker

when used properly, will kill all forms of microbial life, including spores and cysts

Successful sterilization depends on:

proper autoclave operation

proper pack prep

proper chamber loading

Radiation to control microbes:

ultraviolet, gamma or beta rays

sunlight or mercury vapor lamps

used for vx & biologics (modified live virus vx)

used for prepack suture material, gloves & rubber tubing

gas

liquid

Ethylene Oxide

primarily in industries & military

inactivates DNA, prevents cell repro

lower temp than steam

excellent penetration

effective bactericide

explosive & flammable

poisonous

Liquid cheimicals for microbe control

AKA - cold sterilization

soak instruments in disinfectant solutions

may dull edges, but same as autoclave does

sterility not guaranteed

used for minor procedures

clean instruments well

soak for minimum of 3 hrs

change solution q 2wks

label container w contents, date chgd & initials

benzol very common

Iodines

Chlorhex

Alcohols

Phenols

Quaternary Ammonium

Chloride Compounds

Aldehydes

Tincture (2% iodine/ethyl alcohol) - antiseptic - skin only - not commonly used

Iodine Aqueous Solution - antiseptic - cytotoxic - dilute for tissue use - higher levels of free iodine than tincture or idophors

Idophors (iodophors) - antiseptic - iodine w surfactant - may also have detergent - povidone-iodine scrub/solution more commonly used (Betadine)

Aqueous Solutions - Nolvasan solution (also disinfectant) - use on tissue same way as Betadine solution - used as wound lavage if diluted

Scrubs - preoperative scrubs - use on pt or surgeon's hands.  Has soap or detergent mixed in.

evaporates easily

leaves no residue

cytotoxic on mm

ethyl & isopropyl most effective

70% alcohol used on pts, not open wounds

99% alcohol not used on pts, for disinfecting cat gut

preop scrub for hands

contains carbolic acid - hexachlorophene (PhisoHex Hand scrub)

Quaternary Ammonium (disinfectant)

DO NOT mix w bleach

effective against bacteria but not spores/viruses/parvo

Roccal, Benzalkonium Chloride

one of first agents used

common surface disinfectant

broad spectrum bacteriocidal & virucidal

cytotoxic if improper dilutions

Sodium Hypochlorite (bleach)

toxic & irritating

Formaldehyde used for tissue (dead) fixation/preservation for pathology

Gluteraldehyde commonly used in cold trays

See handout!!!