Prevention of disease transmission - Chapter 18-21 Flashcards
What is microbiology
the study of microorganisms
John Tyndall discovered that prolonged exposure to heat ___
destroys heat stable bacteria
Tyndallization is
intermittent heating/fractional sterilization - kills bacteria resistant to heat
Endospores are
heat stable forms of bacteria
Joseph lister discovered the role of ___ in post op infections
airborne microorganisms
To control airborne microorganisms Joseph developed
carbolic acid aerosols and carbolic acid dressings to use in surgery to reduce the amount of microorganisms in the air
Who developed pasteurization, rabies vaccine, and associated micro-organisms with disease
Louis pasteur
pathogens are
disease causing microorganisms
Nonpathogenics are ___ to humans and contribute to ___
beneficial, normal gut flora
Hepatitis A and E are transmitted how
fecal-oral trasmission - not chronic
Hepatitis B,C and D are transmitted through
blood and bodily fluids through percutaneous/mucosal membranes - CHRONIC
Hepa-Titis
Liver-Infection
What are the 5 major microorganisms groups
Bacteria, viruses, fungi, algae, ad protozoa
Bacteria is single cell, temperature broad, and cause ___ infection
opportunistic
normal flora is
beneficial bacteria that protect the host by aiding metabolism and prevent entrance of harmful bacteria
when does bacterial infection occur
when bacteria from one part of the body invades another part
what are the 3 shapes of bacteria
coccus/sphere, bacillus/rod, spirochete/spiral
sphere shaped bacteria form
chains or clusters
spirochete bacteria is spiral shaped to
be capable of movement
Tuberculosis is rod shaped contagious bacteria that is
able to withstand disinfectants
a gram stain is
a 4 step process that separates bacteria into two groups
gram positive bacteria is
purple stained
gram negative bacteria is
unable to hold stain, transparent or pinkish
Aerobes
bacteria requiring oxygen to survive
anarobes
bacteria that thrives in absence of oxygen and is destroyed by oxygen
facultative anaerobes
can live with or without oxygen
what causes antibiotic and disinfectant resistance
capsules
a capsule is a
protective layer surrounding cell wall or bacteria
Virulent
capable of causing disease
The most resistant form of life is
spores
A spore is
bacteria that changes and becomes highly resistant during unfavourable conditions. Alive but inactive
Spores cannot reproduce or cause disease unless
conditions are favourable
What is sued to test the effectiveness of sterilization units and disinfectants
spores
what is used to verify effectiveness or sterilization on spores
an incubator
what is smaller and more fatal than bacteria
viruses
why are viruses more fatal
they are perfect parasite- invading host cell, replicating then destroying host cell and realizing viruses
viruses containing DNA and RNA strands that
change portents and allow for growth and multiplication
specifity is
certain viruses affect certain cells and only those cells
latency or dormancy is when
some cells establish a latent state in host cell and can be reactivated in the future
algae isn’t typically ___
producing human diseases
protozoa is a large group of one cell organisms that
don’t directly cause disease but cause damage to a host if living in one
two types of fungi infections
candida, and oral candidiasis
candida is found where
oral cavity, GI tract and female genitals
prion is short for
proteinaceous infectious particle
prions are made of only
portion, no Dna or rna
what do prions cause
chronic diseases or the brain with long incubation periods
chain of infection
infectious agent >reservoir>portal of exit>transmission>portal of entry>susceptible host
how would you prevent transmission
by breaking the chain
parenteral transmission is
through broken skin
what is a fomite
a inatimate object that can spread disease
what are the 4 types of infections
acute, chronic, latent and opportunistic
the two types of environmental surfaces are
clinical contact surfaces and housekeeping surfaces
clinical contact surfaces have 3 sub categories
touch, transfer, and spatter, splash droplet surfaces
housekeeping surfaces are
floors, walls, sinks, anything not in direct contact with patient
Clinical contact surfaces
anything with high risk of contamination
Transfer surfaces
isn’t directly touched but touches contaminated instruments
Splash, spatter and droplet surfaces
don’t have contact with DHCP or instruments - countertops
how would you deal with and prevent surface contamination
surface barriers and precleaning/disinfecting
when is flash sterilization used
for emergencies, except for implant devices
Bioburden
blood, saliva, bodily fluids
what is a disinfectant
chemical that destroys most pathogens (not spores) - used on inanimate objects
What is an antiseptic
prevents or stops growth of microogranisms (used on living tissues)
Sterilization is the
process in which all microbial life is destroyed
3 levels on disinfectants
high, intermediate, low
what type of disinfectant would you use on a semi critical item that cannot be heat sterilized
high level
an ideal surface disinfectant would
kill TB, EPA registered, not damaging, low toxicity, rapidly kill board spectrum on bacteria and have residual active
Residual activity is
action that continues after initial application
3 levels of patient care items
critical, semi critical, non critical
a critical item is one that
touches bone or penetrates soft tissue (high risk of transmission)
a semi critical item is one that
touches non intact skin /mucous membrane
noncritical items only touch
intact skin
does an ultrasonic cleaner disinfect
no
an external class 1 process indicator is placed where
on the outside/visible area of wrapped cassette/package
what is each package/cassette labelled with
date, load number, initials in heat resistant sharpie
what are the 5 sterilization techniques
steam, chemical, dry heat, ethylene oxide, liquid sterilants
Steam sterilizers are at what temp, pressure and time
121C, 15 PSI, for 3-30 minutes
chemical sterilizers are what temp, pressure and time
131C, 20PSI, for 20-40 minutes
dry heat sterilizers have 2 category’s with what time periods
static air - 1-2 hours
forced air - 6-12 minutes
Ethelyne oxide sterilizers are good for rubbers and plastic because
they use low temps but take 4-12 hours to process then 16 to air out before use
why are liquid sterilants not reccomened
take 10 hours of immersion
expensive to change solution every load
toxic chemicals used
Mechanical monitoring is to
measure and record time, temp and pressure
chemical monitoring shows a
change in color when physical parameter is met
biological monitoring uses a
biological spore to access sterilization process
chemical indicators detect
sterilization failures due to improper loading, packaging or sterilizer malfunctions
biological monitoring is to
determine if sterilization occurred
how would you test a BI
run BI with cycle in middle rack of autoclave, then place in incubator with unsterilized control for 8-12 hours, check for growth
if growth occurs in a BI how do you tell
the color of vile changes to indicate spores are live
chem monitoring class I
heat only, process indicators
process indicators are placed
external
process intergraters are placed
internal
Chem monitoring class II
bowie dick test, rapid eve steam penetration
chem monitoring class III is for
single parameter (heat or pressure)
chem monitoring class IV
multiperameter (heat and pressure, Steam and heat)
Chem monitoring class V is used
inside pack when implantable devices are used, time temp and steam
Chem monitoring class VI is for testing
specific sterilization processes
