Decontamination, Disinfection, And Sterilization Flashcards Preview

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Flashcards in Decontamination, Disinfection, And Sterilization Deck (50):

What is decontamination?

Removal of gross debris (bioburden)
Any physical or chemical process to reduce the number of microorganisms on any inanimate object so that it is safe for handling


What is the importance of decontamination?

Minimize staff exposure
Preserve longevity of instruments
Allow all surfaces to be sterilized
Prevents cross contamination to other pts
Remove pyrogens
Allows direct contact of sterilizing agent


What is disinfection?

Process in which items are freed of contaminating agents and rendered safe for human handling

(Not sterilization, cleaning process that it goes through before the staff can handle and then wrap up to be sterilized)


Methods of instrument cleaning and decontamination

Pre rinsing in OR
Manual cleaning in steril dept
Lubrication (milking)


Explain how the ultrasonic cleaning works

Use high freq sound waves that can clean using cavitation
Also lubricates instruments
Can be used for finer instruments


What is cavitation?

Creation of vacuum tears "bubbles" in the fluid which immediately and violently implode to produce millions of microscopic jets of liquid which gently scrubs items submerged in tank.


What is the typical lifespan of an instrument?

10 years


What is Spaulding's classification of pt care items?

Determines what processing level is required based on how/where item is used.


What are the three levels of Spaulding's classification?

Critical items
Semi critical items
Non critical items


What are critical items?

Items that enter sterile tissue or vascular system.
Surgical implants or needles.
Require high level disinfection


What are semi critical items?

In contact with non-intact skin, mucous membranes, or dirty areas (mouth, nose, rectum).
Breathing circuits, fibre optic endoscopes
Intermediate disinfectant


What are non critical items?

Items that come in contact with intact skin.
Furniture, equipment, floors, BP cuff.
Low level disinfectant


Explain the high level of disinfection

Kills all viruses, bacteria, and fungi.
May kill spores if contact time/conditions are met.
Not effective against CJD


Explain intermediate level of disinfection

Kills most bacteria, viruses and fungi
Ineffective on spores


Explain low level of disinfection

Kills most vegetative bacteria, fungi and least resistant viruses


Methods of physical disinfection

Boiling water - may not kill spores
Pasteurization - hot water decontam/disinfection with chlorine agents.
Ultravioloet radiation - denature DNA and proteins


Chemical methods of disinfection

Alcohol, chlorine compounds, formaldehyde, cidex, iodophors, phenolic compounds, hydrogen peroxide.


What is cidex?

2% Gluteraldehyde.
Chemical immersion, must be activated, color change, needs testing, 20-30 min soak, requires rinsing and PPE


What are the advantages of single use items?

Sterility guaranteed if package intact
More aesthetically acceptable to pts
Prevent cross contamination
More comfort to pts
Eliminates expensive mechanical cleaning


What are the disadvantages of single use items?

Costly if accidentally opened or contaminated.
No deviation from custom packs
A defect in one could be in all
May open high number of packages
Inadequate inventory might not be kept
FIFO first in first out


What is sterilization?

Process by which all microorganisms are killed, including spores.


What is the most resistant living organism?

Bacterial spores.


What are the four types of monitors used during sterilization?

Administrative - work practices monitored (reciepts), written policies and procedures are followed.

Mechanical indicators - recording charts and graphs, gauges, thermometers, timers, daily function tests.

Chemical indicators - external tape and internal strips

Biological indicators - to ensure functioning properly and microorganism in tiny container that was processed was killed which means entire load is sterilized.


What would a positive reaction from a biological indicator look like?

Cloudy growth
Colony forming units
Color change


What is important to know about instruments going through the cleaning/ sterilizing process?

Clamps need to be ope n, scissors open, instruments that can come apart should, lumen instruments should be horizontal, separate unlike metals, cupped surfaces face down, open hinges and box locks, on absorbent towel, ring handles on stringers, sharp and delicate instruments should not touch other instruments.


What is important about the instrument packaging for sterilization?

Permits penetration of sterilizing agent
Can withstand physical conditions of agent
Maintain integrity
Impermeable to microorganisms
Covers items completely
Tear and puncture resistant
Allows identification of contents
Dry fast
Free of toxic ingredients
Lint free or low linting
Protects content from physical damage


What are some materials used for wrapping surgical instruments?

Woven fabrics
Non woven fabrics
Peel packs or pouches
Wrapped trays
Sealants and labelling
Wrapped trays
Rigid closed containers


Explain woven fabrics re sterilization

Not moisture resistant
Need to use double thickness esp for heavy pans
Sewn together on edges only
Withstand laundry 50-70 times
Rehydrate after sterilization
Stored at rm temp
Inspect for holes before use
CAn use patches to seal holes if necessary


Explain non woven fabrics

Cellulose, rayon, and nylon
Available in different weights
Excellent barrier against microorganisms and moisture
Lint free


When are peel packs or pouches used for sterilization?

For odd shaped or single instruements


Explain wrapped trays

Allow steam penetration
Prevent trapped air in tray
Cannot be solid
Absorbent towel on bottom of tray prevents snagging of instruments or perforations
Double wrapped in woven or non woven material
Allowed to cool and dry before use


Explain rigid closed containers

Metal or plastic
Stainless steel mesh or perforated basket insert
Lid affixed with metal snap locks
Load identifying labels attached before sterilization
Single use air filters in top and bottom

Specialized sets are provided by manufacturer


What are the methods of sterilization?



What type of sterilent is used in an autoclave?



What are the types of thermal sterilization?

Steam under pressure
Dry heat


Minimum time temps for steam sterilization?

4 mins at 270 degrees Fahrenheit
18 mins at 250 degrees Fahrenheit


Advantages of thermal sterilization?

Easiest and safest
Least expensive and most easily supplied
Automatic controls and recording devices
No harmful residue on instruments


Disadvantages of thermal sterilization?

Prepare instruments
Need to be free from grease and oil
Instruments that are heat sensitive cannot go through
Need direct contact on all areas
Timing cycles need to be adjusted based on material of items
May cause stains


Types of steam sterilizes?

Gravity displacement
Flash/high speed pressure


What is a flash sterilizer?

Can be gravity or pre vacuum based cycles.
Higher heat for shorter period of time.


When would dry heat be used?

For oils, talc, and petroleum products.


What types of dry heat are available?

Mechanical convection oven
Gravity convection oven


Advantages of dry heat

Penetrates substances that other methods can't
Protects cutting edges of sharp instruments


Disadvantages of dry heat

Long exposure period
Time and temp will vary depending on substance
Overexposure may ruin some items


What are the methods of chemical sterilization?

Ethylene oxide gas (ETO)
Hydrogen peroxide (sterrad)
Per acetic acid (steris)


Chemical sterilization- explain ethylene oxide gas

Very harmful
Colourless gas
Safe for instruments


What are advantages for ETO?

Can be used in items that cannot tolerate heat
Completely penetrates all porous areas
Automatic controls
No film on instruments
Non corrosive and will not damage instruments


Chemical sterilization - explain sterrad or hydrogen peroxide

Low temp
Used for het and moisture sensitive items.
Good for plastics
Not as fast as steam
Non corrosive


Chemical sterilization - peracitic acid or steris

Liquid chemical
(Machine by theatre 12)
Low temp
Alternative for instruments with lumens and fibre optics
Items must be used immediately within 4 hours
Environmentally friendly
30 minutes
Non corrosive
Not For moisture resistant


What is radiation sterilization?

Uses gamma radiation
Low temp
Long time, expose for 10-20 hours
Penetrates most material
Used for heat and moisture sensitive
No residual radiation generated.
Custom packs are done this way