L03: Preparation for Aseptic Surgery (Kim) Flashcards
sources of infection during a surgery
instruments local skin flora hair/dirt/debris surgeon skin flora surgeon attire operating table air-borne from room
Halsted’s Principles for good surgical outcomes
asepsis gentle tissue handling hemostasis preserve blood supply reduce dead space avoid tension anatomic dissection
If all are followed, should achieve <5% infection rate for clean procedures
sterilization vs. disinfection/antisepsis
sterilization: destruction of ALL living organisms w/ no toxic residue and no instrument damage
disinfection/antisepsis: decreases number of organisms, but does not get rid of all of them
methods of PHYSICAL sterilization
dry or wet heat
radiation
filtration
methods of CHEMICAL sterilization
ethylene oxide (most common)
H2O2 plasma
gluteraldehyde (“cold sterilization”)
Dry vs. Wet Heat sterilization
Dry Heat: no humidity, slow, death by oxidation, can burn objects and temper metal, rarely used
Wet Heat: 100% humidity, rapid, water catalyst for coagulation and protein denaturation, reliable, inexpensive, non-toxic
how does steam sterilization (autoclave) work?
- attains appropriate temperature and duration
- pressurization used to achieve higher temperature (but doesn’t in itself kill the bacteria)
- the higher the temp used, the less time required to sterilize
FLASH method
270 degrees for 3 minutes; often used when instrument dropped
- not protocol or gold standard
- used on emergency basis
shelf life of single wrap muslin
2 days
shelf life of double wrap muslin
3 weeks
shelf life of crepe paper and single layer muslin
10 wks
shelf life of polypropylene peel pouches
12 mo. (probably indefinitely)
what not to autoclave
many plastics
suture material
electronics
powders, glassware, liquids
danger of ethylene oxide
- colorless, odorless, toxic gas
- can create ocular irritation: must aerate objects for hours to days to prevent this
adv. of ethylene oxide
can manipulate concentration, humidity, and temp. to alter sterilization times
radiation
works via lethal ionization
gamma radiation most popular
-used to sterilize commercially products (mass quantities of suture, gauze sponges, implants, etc.)
type of indicators
physical chemical (ie. turns black when get to certain temp, but doesn't tell you how long something was exposed to that temp) biological (disad: delay in knowing since culture takes several days)
can you sterilize skin?
no; will be about 20% residual bacteria left over
antiseptic agent
- used for scrub onto patient, clinician
- reduces bacterial population on patient and surgeon
- can be toxic to tissues; use at appropriate dilution
antiseptic vs. disinfectant
antiseptic: used on living tissue
disinfectant: used on inanimate object
* same agent can be classified as both*
properties of chlorhexidine
non-irritating good residual activity not affected by organic matter effective against wide array of microbes allergies/irritation possible after chronic exposure ototoxicity corneal toxicity most common antiseptic used
properties of iodophors
cheap effective against wide array of microbes can cause dermal irritation decreased activity in organic matter unreliable residual activity stains
properties of alcohols
very rapidly acting cheap decreased activity in organic matter poor residual activity* drying effect on skin rapid heat dissapation (can expedite hypothermia during surgery)
anything belowe waist or on back is considered sterile/not sterile
not sterile
