Sterilization and Disinfection Flashcards
what are the routes for transmission during dental procedures
direct contact w saliva or blood or infectious lesions
fomites= indirect transmission via contaminated objects
spatter of body fluids
aerosolization of body fluids
Ebola description
ebola= highly infectious, moderately contagious, 50% fatality rate transmitted by direct contact of infected body fluids, incubation of 2-21 days enveloped virus killed by alcohol hand sanitizers can survive via fomites for several hours
HIV description
HIV= low risk of transmission from pt to worker vice versa, low occupational risk. no documented cases of infection in dental workers. standard infection control is effective immediate post exposure antiviral therapy highly effective
Hepatitis B
300 k infected every year, 80% infections undiagnosed, 1 million carries, high occupational risk, vaccine available!
TB
low risk of transmission, epidemic resurgence, coughing produces infective aerosols, not transmitted by fomites
Herpes
1 and 2 frequent in oral cavity can be transmitted to healthcare workers. ocular herpes= blindness. viral whitlow on finger. may be transmitted from workers to pt
what are other transmittable diseases we are concerned about
seasonal flue, dental pathogens, HPV
prevention of disease transmission
sterilization of instruments, disposable supplies, unit dosing, disinfection of surfaces. barriers, hand antisepsis, immunizations
Immunizations recommended for HCP by CDC
Hepatitis B, influenza, measles, mumps, rubella, varicella zoster
what are critical items
critical items come into contact with tissue or the vascular system - burs, needles, blades
what are semi critical items
semi critical items- items come into contact with mucous membranes or non intact skin (curing light)
what are non critical items
items that touch intact skin (BP cuff)
what is sterilization
sterilization is the destruction or removal of all forms on life including spores. can be heat or chemical only used on inanimate objects
what is sterilization used on
you sterilize critical and semi critical objects
what are disinfectants
disinfectants inhibit or destroy pathogens but NOT spores used only on inanimate objects
what are disinfectants used on
non critical surfaces
what are antiseptics
antiseptics are used to destroy pathos microorganisms on living tissues and are safe for human use
what are antiseptic used on
living tissue
can antiseptics and disinfectants be used interchangeably
NO!!
what is high level disinfection
destroys all microbes but NOT spores
what is intermediate level disinfection
inactivates TB, vegetative bacteria, viruses, fungi BUT NOT spores
what is low level disinfection
kills most bacteria, some viruses, some fungi but not resistant microbes such as TB and spores
describe critical items
enter sterile tissue or the vascular system and must be sterilized
describe semi critical items
contact mucous membranes or non intact skin. sterilize if possible, HIGH OR INTERMEDIATE LEVEL disinfection
describe non critical items
come in contact with INTACT skin but NO mucous membranes use LOW level disinfectant
describe heat sterilization
saturated steam under pressure, dry heart. heat is most efficient and reliable bc it denature proteins killing microbes; however items must be cleaned before to limit bioburden
Describe steam sterilization autoclave conditions
autoclave= oldest. 121 C (250 F). 15 psi . 15-20 mins with packaging material that allows for penetration of steam
NO Metal or glass containers
Advantages of autoclave
disadvantages of autoclave
advantages: short, good penetration
disadvantages: corrosion of steel and dulls edges, deposits from hard water, may be wet at end, destroys heat sensitive materials
describe flash steam sterilization
statim brand hotter than autoclave but faster
how does dry heat sterilization differ from steam sterilization
requires higher temps for linger times
advantages of dry heat sterilization
disadvantages
advantages: does not corrode or dull edges
disadvantages: long, may discolor, destroys heat sensitive materials, rubber. and impression trays. unsuitable for handpicks
CAN NOT BE DONE IN A COOKING OVEN!! has to be a FDA approved unit
describe rapid heat sterilization
very very hot, fast!, does not corrode or dull but can’t use for handpieces!
unsaturated chemical vapor sterilization
depends on heat, water, and chemicals. items have to loosely packed and dry 131 C (270F) . 20-40 mins.
advantages of chemical vapor
disadvantages of chemical vapor
\+ = short cycle time, does not corrode or dull - = chemical concerns, must be dry before use, chemical needed, heat sensitive material destroyed
what is required by the CDC and ohio state law
monitoring of sterilization units
what doe chemical treated tapes and heat sensitive tapes indicate
that package has been heated NOT that sterilization temps were reached - thus they DO NOT ensure adequacy of sterilization cycle
what provides the best guarantee of sterilization
biological monitoring
how is biological monitoring done
- glass vial w suspended pores plus pH indicator- if spore germinate indicator changes color
- spore impregnated strips in glassine envelopes that are sent to service for checking - most widely used!
when does one use chemical sterilization instead of heat?
when heat is inappropriate
Ethylene oxide
carcinogenic- alkylating agents. gas mixed w freon, EXPLOSIVE will burn tissue 25 C (75 F) 10-16 hours packaged in paper or plastic
glutaraldehydes
used the most. effective against vegetative bacteria, TB
glutaraldehyde conditions
10 hours at room temp immersed in solution
+ of glutaraldehyde
- of glutaraldehyde
+ most potent chemical germicide, active in organic debris
- long, rinsing needed, allergenic, tissue irritation, biologically non verifiable cannot package items, corrosive
