Module 6 Flashcards
(29 cards)
Sterilization
- destroys ALL forms of microbial life
- no degrees of sterility: article is sterile or not sterile
Disinfection
- destroys pathogens
- other microbes and spores may survive
- several levels
- usually involves chemicals
“Terminal disinfection”
-disinfection procedure when patient leaves area; done before next patient arrives
Antisepsis
disinfection mild enough for living tissue
sanitation
- disinfection of eating utensils and dishes
- mechanical or chemical
- agents used must not alter properties of food
cleaning
- removal of soil/body secretions
- does not imply disinfection
- often used is soap and H2O
cidal
- suffix meaning death
- used to denote agents that kill various types of microbes ex. germicide, bactericide, viricide, sporicide, fungicide
static
- used to denote agents or procedures that stop microbial growth, but do not kill
ex. bacteriostatic, fungistatic
SUD
-Single Use Device
Item to be used only once and then discarded
ex. needles, catheters, syringes that have been in contact with body fluids
Sterilization
- kills everything
- what needs to be sterile:
- anything contacting sterile tissues in body (surgical instruments, needles, catheters)
- containers to collect patient specimens for the microbiology lab
- contaminated materials before disposal (used dressings, used needles, lab cultures)
Three methods of sterilization
- Incineration
- autoclaving
- ethylene oxide (ETO)
Incineration
- terminal decontamination for biological or disposable waste (used needles, lab cultures, bandages, blood samples)
- burn at very high temperature –> reduce everything to ash
- now usually done off-site –> health care facility must adhere to TDG (transportation of dangerous goods) regulations
Autoclave
- steam under pressure, “moist heat”
- optimum temperature: 121 degrees, pressure: 15 psi, time: 15 minutes
- reloading:
- items perforated tray
- load loosely
- dry goods on edge; lids ajar; jars, canisters, tubes–> on sides
- testing for efficiency:
- spore strips placed in autoclave (center and bottom)
- place strips in culture medium after autoclaving –> incubate –> check for growth
- growth means spores not killed–> autoclave not working properly
- items suitable for autoclaving
- surgical instruments
- dressings (before use)
- surgical gowns
- anything that has to be sterile and can withstand heat
- not good for plastics or rubber
- most items wrapped in protective packaging (cloth/paper) that steam can penetrate
- indicator on package that can change color during autoclaving so can distinguish sterile from nonsterile packages
- if packaging gets wet, items may no longer be sterile
Ethylene Oxide (ETO)
- gas sterilization; no heat
- use for heat sensitive items (especially plastics)
- large capacity
- slow (8 hours)
- expensive
- toxic to human tissue
Desirable properties of disinfectants
- broad spectrum: kill lots
- rapid action
- resistance to inactivation by other material
- nontoxic, odorless, nondestructive
- residual action
- user friendly
- economical
Spaulding’s classifications for items requiring disinfection/sterilization
-Critical: items going into sterile area of body; must be sterile
-semi-critical: items going into or touching area of body that is not sterile; no pathogens, but dont have to be sterile
-non-critical: items not going into body, but may touch body surface
ex. beds, countertops
It is okay to have microbes but dont want any that can be inhaled and cause infection
Resistance of microbes to disinfection
Least resistant:
- vegetative bacteria- least resistant (easiest to destroy)
- lipid viruses (except hepatitis B)
- fungi
- nonlipid viruses
- tubercle bacilli (difficult to destroy)
Most resistant:
-bacterial spores
Levels of disinfectants
Low level
-kill vegetative bacteria and lipid viruses; other stuff may survive
Intermediate level
-kill everything except maybe nonlipid viruses and bacterial spores
High level
-kill everything if sufficient time; essentially sterilants
Low level disinfectants
A. Detergents and soaps
review summary sheets
Intermediate level disinfectants
B. Alcohols (ethanol and isopropyl alcohol)
C. Chlorine containing Agents (bleach)
D. Iodine (iodophores)
E. Phenolic Compounds
(review summmary sheets)
High level disinfectants
F. Glutaraldehyde
G. Peroxygens
(review summary sheets)
Mechanical disinfection:
Pasteurization
- 75-77 degrees; 30 mins
- intermediate level disinfection; kills everything but spores
- use: reusable tubing from respiratory equipment
- economical
Mechanical disinfection:
Filtration
- use filters with small spores to remove microbes from liquids and air; microbes larger than pore size do not pass through (including larger viruses)
- uses:
- membrane filters- remove microorganisms from fluids -IV solutions, drugs, vaccine
- respiratory therapy equipment- to keep patient bugs out of other parts of the equipment/ surrounding air
- HEPA filters: for air filtration- isolation rooms, drying cabinets, lab safety cabinets
Microfiber cloths
Used for environmental cleaning of surfaces
