wk 4- cleaning Flashcards
describe the 3 categories of items and the degree of risk in transferring infectious agents to patients
non-critical items- come into contact with intact skin only and require regular cleaning and low level disinfection to remove transient infectious agents
semi critical items come into contact with non-intact skin or mucus membranes. must be disinfected or single use or sterilized prior to use.
critical items come into contact with sterile tissues and body cavities and must be sterile.
transient infectious agents are what
ones that colonies on superficial layers of skin and are picked up and put down on surfaces.
cleaning is defined asand used for what items
removal of organic material that may support the growth and persistence of infectious agents using detergent
used for noncritical items and minimal touch areas like floors
disinfection defined and used for what items/events
destruction and removal of infectious agents resulting in a reduction in the number of living infectious agents to an acceptable level with physical/chemical controls
used for reprocessing noncritical items and high touch areas
sterilisation
results in the complete destruction of ALL living infectious agents. used for reprocessing semi critical and critical items.
must be cleaned (organic material) before sterilised as ingredients could become inactive with organic matter
key word LIVING
chemical agents are only effective if the interaction has the correct 4
contact- free of organic matter
exposure time
adequate concentration
choice of agent
physical control methods to kill/control growth of infectious agents 4
temperature extremes
pressure
filtration
irradiation
temperature extremes as a physical control method
high >100 degrees C and low <4 degrees C temperatures can be used to kill (high) or control the growth of infectious agents (low).
Dry heat - incineration which is broad spectrum and sporicidal.
moist heat more effective than dry heat because water penetrates cells easily.
high temp is not suitable for heat sensitive or molecules.
pressure as a control method
autoclaving (steam under pressure) most commonly used. 121 C, 15 psi, 20 mins. It is broad spectrum and sporicidal.
filtration as a method of control
it sifts infectious agents out of solutions through administrated fluid/medicine. (positive pressure)
irradiation control method
non ionizing radiation- doesn’t remove electrons from atoms/molecules and has low penetrance such as UV light. surface irradiation but not sterilization of dense materials
ionizing radiation- gamma rays that sterilize dense material by removing electrons from atoms and molecules of air, water, liquids and. living tissue.
chemical control methods list 6
alcohols
halogens
quaternary ammonium compounds
phenolics
hydrogen peroxide
aldehydes
when to use autoclaving
extreme temps.
incineration
filtration
radiation
auto- heat/moisture tolerant medical devices/solutions
extreme temps- food
incin- biological waste. left over meds
filtration-heat sensitive solutions
radiation- surfaces (uv) and plastics/medications (ionizing)
alcohols as a chemical control method
at concentrations of 60-90% are highly effective surface disinfectants and antiseptics if air dry.
halogens as chemical control
such as sodium hypochlorite (bleach), iodine and chlorhexidine are broad spectrum and effectively disinfect drinking water, mouthwash, contaminated surfaces and skin. they are inactivated by organic material and are corrosive
