DISINFECTION & STERILIZATION
Bander AL Asmari,
CRCST, CIS, CPSBD
Getting from here…
Back To Here:
Outline
• Cleaning & Decontamination
• Disinfection
• Prep & Pack
• Sterilization
• Terminal
• Point of Use
• Quality Assurance & Monitoring
• Sterilization Process Failure
Good old Dr. Earle Spaulding
• The selection of a disinfection or
sterilization method depends on the
intended use of the item.
• Non-critical requires low level disinfection
• Semi-critical requires high level disinfection
• Critical requires sterilization
Definitions
• Cleaning—Removal of contamination from an item
to the extent necessary for further processing or for
intended use.
• Decontamination—The use of physical or chemical
means to remove, inactivate, or destroy blood-
borne pathogens on a surface or item to the point
where they are no longer capable of transmitting
infection and the item is rendered safe to handle
with the ungloved hand.
Definitions
• Disinfection—The process that kills pathogenic and
other microorganisms by physical or chemical means.
• Low
• Intermediate
• High Level
• Sterilization—Free from viable microorganisms.
• This is actually just a probability.
• Sterility Assurance Level (SAL)= 10-6th power, or 1:1,000,000
chance that a single viable microorganism is present on a
“sterilized” item.
AORN Standards & Recommended
Practices
Recommendation #1 “Items to be processed should be categorized as critical,
semicritical, and noncritical.”
• NonCritical: Contact with intact skin but not mucous
membranes
• Clean with low-level disinfectant : kill bacteria,fungi and
some viruses, won’t kill spores
• Ex Alcohol, quaternary ammonium (virex)
• Intermediate level disinfection is also mainly for
environmental surfaces
• Used on noncritical items that have been exposed to
pathogens that aren’t killed by low level disinfection.
• Examples: Halogens (chlorine, iodine), Phenolics
(carbolic acid)
• Relatively fast acting
• Relatively broad spectrum
Semi-Critical:
Contact with mucous membranes or broken skin
• Require high level disinfection but do not have to be
sterile at point of use
• Examples: Gluteraldehyde, Ortho-Phthaldehyde (OPA),
Formaldehyde, Cidex OPA
• All have a use life after opening package
• May have an obnoxious odor
• Use test strips to ensure MEC
• Need proper venting
• Need copious rinsing—particularly with OPA
• Need documentation
Critical Items
Object that carry a high risk for infection if contaminated,
things that will enter sterile tissue.
High level disinfection +sterilization
It all starts with cleaning
• Items can’t be disinfected or sterilized unless they are
properly cleaned.
• AORN: “Cleaning and decontamination are the initial
and most critical steps in breaking the chain of disease
transmission.” 2011 pg 401
Cleaning & Decontamination
• Cleaning begins at the point of
use.
• AORN RP: Care of Instruments
Recommendation #4—
Instruments should be kept free
of gross soils during surgical
procedures
• Use enzymatic spray at the end
of the procedure
Flush lumens & cannulas!!!
Cleaning & Decontamination
• Soiled instruments need to be contained and confined
for transportation to the soiled utility room or to SPD.
Cleaning & Decontamination—after the
procedure
• The first step is to remove all visible and invisible soils
• Must be done according to manufacturer’s guidelines
• Neutral PH enzymatic detergent, mechanical friction
• Next step is generally the mechanical washer
Cleaning & Decontamination
• AORN RP: Care of Instruments, Recommendation
#5—Cleaning and decontamination should occur as
soon as possible after the instruments are used.
• AAMI: Instruments are decontaminated within 15-60 minutes
after use.
Final point on cleaning and
decontamination
• Anything that can be disassembled must be disassembled
for cleaning, decontamination, and sterilization
• Copious rinse with RO, DI or distilled water
What’s next?
• Disinfection
• Use a germicidal solution
• Follow manufacturer’s guidelines regarding dilution
• Must come in contact with all surfaces
• Must remain in wet contact for the prescribed amount of time—
read the label
Disinfection
• Thermal!!! Using Mechanical Washer-Sterilizer
• Washes with cold water then fills chamber with steam
• Heat denatures proteins at lower temperatures if steam
is present
• Pressure is used to achieve temp of 270 deg.
• Goal is steam saturation of 100%
Inspect & Assemble
• Regardless of who is processing the instruments, they
need to be inspected to make sure they’re clean and in
good working order before they go into a sterilizer
Packaging
• Instruments that are terminally sterilized are placed into
some kind of package before they go into a sterilizer
• Rigid container
• Flat wrapped
• Peel pouch
Sterilization
• Terminal Sterilization—sterilized in a package, has a
shelf life
• Point of Use Sterilization—no shelf life, needs to be
delivered to the sterile field at the completion of the
sterilization cycle.
Steam Sterilization
• Most common method of sterilization
• Has been used for many years
• Relatively safe
• Relatively inexpensive
• Can be used for the majority of surgical instruments
Steam Sterilization
• Phases
• Condition
• Sterilize
• Exhaust
• Dry—needs to cool to room temperature before handling
(sterility assurance and condensation)
• Need to make sure all parameters for sterilization have been
met prior to releasing the instruments for patient use.
Steam Sterilization
• Cycle selection needs to be in accordance with
manufacturer’s guidelines
• Terminal sterilization cycles all take around an hour.
• Common Cycles
• Prevacuum 270’ 4 minutes
• Prevacuum 270’ 8 minutes
• Gravity 250’ 30 minutes
Hydrogen Peroxide Gas Plasma
• Used for heat and pressure sensitive instruments
• Relatively safe
• More expensive than steam sterilization
• Fast cycle times—48-75 minutes
• Good for batteries, shavers, fiber optic scopes
• Not for use with paper or cloth
Hydrogen Peroxide Gas Plasma
Sterilizer
Hydrogen Peroxide Gas Plasma
• Cycles:
• Non-lumen: 20-40 minute cycle for batteries & other non-
lumened items.
• Lumen cycle: 55-75 minutes for items containing lumens, mixed
loads, complex items
• Flexible scope cycle: 75 minutes, allows for terminal sterilization
of selected flexible endoscopes
Point of Use Hydrogen Peroxide Gas
Sterilization
• Used for terminal sterilization of scopes
• Able to use for instruments that are moisture
sensitive
• Cycle time: 28 minutes
• Requires packaging
• Chamber is small
Automated Endoscope
Reprocessor
• Automated equipment designed to clean,
disinfect, and rinse flexible scopes
• “High level decontam”, not sterile
• AER’s are a chemical process;
Gluteraldehyde, OPA, and Paracetic acid
are the most common chemicals
Automated Endoscope
Reprocessor
Sterilization Quality Control
• How do I know my item is safe for the patient???
Sterilization Quality Control
• Physical monitoring—instruments within
the sterilizer that tell us the temperature,
pressure, and duration of a sterilization
cycle.
• Process indicators—let us know whether
or not the item has been processed
External Chemical Indicator Tape
Before Processing After Processing
Sterilization Quality Control
• Tamper evident device—container locks, tape, arrows
• Internal Pack Control—chemical indicators placed
inside the tray, let us know that several parameters for
sterilization have been met
Examples of
Internal Chemical Indicators
Sterilization Quality Control
• Biological Monitoring—spores inside a
test package that measure the lethality of
a sterilization cycle
• Always run a BI with implants
Biological Indicators
• Contain Geobacillus stearothermophillus- Highly heat
resistant, spore-forming bacteria does not produce
toxins and is non-pathogenic.
Sterilization Quality Control
• Bowie Dick Test—used to assure the air removal
system is working properly in a prevacuum sterilizer
• Daily
Sterilization Quality Control
• Lot control number—includes sterilizer
identification, cycle number, date of
sterilization
• This is how we achieve lot traceability
• It’s up to the clinical staff to record lot control
number in the patient’s record.
Load Control
Information*
Sterilizer
S-1 L-5 Load
Number Number
05-03-07
Date Sterilized
*Must be placed on each item Sterilized
in the Central Service Department.
Sterilization Quality Control
• In order for a sterilizer load to be released for
patient use:
• Sterilizer tests complete
• Parameters for sterilization must be met
• Process indicator (tape) must pass
• Tamper evident devices present
• Lot control present & accurate
• Packages cooled to room temperature if
terminally sterilized
• If implants, BI must pass
Sterilization Quality Control
• What can go wrong???
Parameters for sterilization not
met
• Parameters: Time, Temperature, Pressure,
Concentration
• Reprocess the load in another sterilizer
• Take the sterilizer out of service until the cause can be
identified and corrected
• Usually something has gone wrong with the sterilizer &
sometimes the plant
Sterilization Process Failure
• Positive Biological Indicator
• Need to recall back to the last negative biological
• Take the device out of service until the cause of the problem can
be identified and corrected
• Most of the time it’s user error
• The rest of the time it’s caused by a problem with the sterilizer or the
plant
Sterilization Process Failure
• Wet load/wet pack
• May be inside the chamber
• User error—improper loading of the chamber
• Sterilizer—valve or trap problem
• Plant—steam too wet
• Reprocess the load in another sterilizer; take the sterilizer out of
service until the cause can be identified and corrected
Sterilization Process Failure
• Wet load/wet pack
• May be inside the packages—can’t tell until they are opened.
• Usually a condensation issue
• Items moved before they have cooled to room temperature
• Improper configuration of tray
• Improper configuration of sterilizer load
• Excessively heavy tray
• Mixed metals and plastic
• Trays with moisture are considered contaminated—notify SPD and
replace the tray. SPD needs lot control # in order to conduct a recall
Internal Pack Moisture
Moisture set
Other things that can go wrong
• Hole in wrapper
• Items get handled many times and every time they are touched,
there’s a chance the wrapper may get damaged
• Lift—don’t drag
• Watch out for trays that have feet or are very heavy
• Rigid Container Defect
• All parts have to be intact
Other things that can go wrong
• Peel pack has wrinkles in the seal
• Tamper evident device comes off
• Indicators missing
• Item falls on the floor
Thank you
• Questions??
