Download Infection control measures III

Dr. Abdelmonem Altarhony
Infection control measures III
Objectives
At the end of the course, the students should have
an understanding of:
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Sterilization and disinfection :
Instruments infection control
Surfaces disinfection
Instrument Processing
Types of sterilization
Disinfection and Sterilization
• Methods that break the chain of infection or interrupt
the infectious disease process:
Disinfection
The process of destruction
of pathogenic microorganisms by
direct exposure to chemical and
physical agents.
Disinfection and Sterilization
Antiseptics
Chemical disinfectants which can
be safely applied to skin or mucous
membrane and are used to
prevent infection by inhibiting the
growth of bacteria.
Sterilization
The process by which an article, surface or
medium is free of all viable microorganisms
either in the vegetative or spore state.
• Antiseptics:
Clorhexidine. Antiseptic
• Skin and mucous membranes
• Less active against Gram –
• Limited virucidal, tuberculoidal and
sporicidal activity.
Recommended as mouth rinse before
clinical procedures.
Disinfectants
• Activity is reduced by organic debris or blood.
• Disinfection can not occur until fresh
disinfectant is reapplied to a thoroughly
cleaned surface.
• Disinfection does not sterilize.
Disinfectant
• Hypochlorite's
• These broad spectrum, inexpensive,
fast acting are of choice against
viruses such as Hepatitis B and C and
HIV viruses.
• Not much useful against spores
• Bleaching activity
• It is recommended for disinfection of
counter tops and work surfaces.
• Recommended for disinfection of
blood spills ( 1:10 dilution )
Phenolic
Chloroxylenols (Dettol and Lysol )
•Broad spectrum activity, effective
against gram + and – bacteria, fungi and
yeast.
•They are not effective against non
enveloped viruses and spores.
Cleaning and disinfection of surfaces.
Alcohols- disinfectant and
antiseptic
• There are two water-soluble alcohol that can be
used in disinfection: ethyl alcohol and isopropyl
alcohol.
• Mode of its action : denaturing bacterial proteins.
• Flammable
• Bactericidal against Gram + and Gram,tuberculocidal, fungicidal, and
virucidal against enveloped viruses
(HIV, influenza, herpes viruses).
Alcohols- disinfectant and
antiseptic
• Not effective against bacterial spores and have
limited effectiveness against nonenveloped viruses
(adenovirus, rotavirus)
• Concentration required : 60-90% in water
• Higher concentrations are less effective as the action
of denaturing proteins is inhibited without the
presence of water.
Surfaces disinfection
• Wipes, sprays and foams typically use less volume of
product than solutions do. This reduces exposure to
chemicals. Wipes use the least product, are quick to
use, and are less likely to cause aerosolization,
splatter, or dripping of the product.
Iodine Antiseptic
• Iodine is rapidly bactericidal, fungicidal,
tuberculocidal, virucidal, and sporicidal.
2% iodine in 50% alcohol (tincture), which kills more
rapidly and effectively than alcohol alone.
Skin disinfection and pre-operative preparation of skin.
• Triclosan
Broad spectrum antimicrobial
It is widely used in handwashing and
surgical scrubs > 1 % concentration.
Two recent US studies (Fischler et al.
2007, Fuls et al. 2008) demonstrated that
hand washing with antimicrobial soap
containing triclosan (0.46%) reduced
bacterial load and transfer of bacteria
from hands, compared to handwashing
with a non-antimicrobial soap.
Instrument infection control
Critical, Semicritical and
Noncritical Instruments
Proper Techniques and Sequencing
of Procedures
• Cleaning Prior to Disinfection or Sterilization
• Spray enzymatic foam onto non-disposable
instruments and trays to start cleaning process.
• Remove all debris is the essential first step in proper
disinfection or sterilization.
• The presence of visible or non-visible debris or
organic substances may interfere with disinfection
and sterilization.
Ultrasonic and sonic
vibration:
High frequency sound waves beyond the sensitivity of
human ears are called as ultrasonic waves.
• It is the safest way to clean sharp instruments.
Stubbs B. et all, 1992.
• They have the property to disrupt the cells but the
results have been variable between good and poor
if used without periodic testing and maintenance.
• Gram negative rods are more sensitive to ultrasonic
vibration whereas Gram positive cocci, spores of
fungi and bacteria are resistant to the vibration.
Packing & Sterilizing
Do and Don´t of Instrument
Recycling
Do the following:
• Wear protective puncture-resistant gloves to handle
used instruments.
• Keep instruments wet in an antibacterial solution
before cleaning.
• Use an ultrasonic cleaning device.
• Use good quality sterilizer equipment.
Do and Don´t of Instrument
Recycling
• Have steriliser annually inspected regarding gaskets, timer,
valves, and temperature and pressure gauges.
• Place only dry instruments in the sterilizer.
• Use a wrap that will be penetrated by the steam or gas
used.
• Load the sterilizer loosely; leave space between large
packs.
• Keep a record of daily indicators and weekly spore tests.
Don´t do the following
• Place wet instruments into any type of sterelizer
unless so instructed.
• Overwrap cloth packs or use impermeable
wraps for steam or chemical vapor pressure
sterelization.
• Use closed, non perforated trays, foil, canister,
or other sealed containers in gas or steam
sterelizers.
• Overload or cram packs toguether in the
sterilizer.
• Decrease the required time for sterilization .
• Add instruments to a sterilizer without restarting
the cycle.
Steps in cleaning and
disinfecting
Step 1
Step 2
• 1. Rinse the article with
• 2. Wash the article in hot
cold water to remove
water and soap.
organic materials
• Note: the emulsifying
• Note: hot water coagulates
action of soap reduces
the protein of organic
surface tension and
material and tends to make
facilitates the removal of
it adhere. E.g. of organic
dirt. Washing dislodge the
material- pus and blood
emulsified dirt
Step 3
• 3. Use brush and or
bristle to clean the
grooves and corners.
Scrubbing helps to
dislodge foreign
materials
Step 4
• 4. Rinse the article well
with warm water-hot
water
Step 5
• 5. Dry the article. It is
considered clean but
not sterile.
Step 6
• Clean the brush,
gloves and sink. These
are considered soiled
until they are cleaned
appropriately, usually
with disinfectant
Breaking the chain of
infection: Instrument Proce
Sterilization
1. Heat sterilization
2. Chemical sterilization
3. Radiation sterilization
1. Heat Sterilization
It is the simplest, most effective and inexpensive
method.
Types of heat sterilization :
a)Steam sterilization (Autoclaving)
b)Dry heat sterilization
Dry-Heat Sterilization
Advantages:
• It is effective and safe for metal instruments
because the process does not dull instrument
edges or rust/corrode the instruments.
Disadvantages:
• Less reliable than autoclaving
• Many materials do not tolerate
• dry heat (as media)
Dry-Heat Sterilization
• Heating at atmospheric pressure and often use a fan to
obtain uniform temperature by circulation.
• Heat at 180º for half hour , 170º for 1 hr., or 160º C for 2
hrs.
Temperature (°C)
120
140
150
160
170
180
Time (minutes)
480
180
150
120
60
30
Steam Sterilization (MOIST
HEAT )
• Steam appliedd under pressure (1210 C for 15
min) is the most effective method of moist
heat sterilization.
• The steam must directly contact the materials
to be sterilized.
• Don´t overload.
Steam Sterilization (MOIST
HEAT )
Advantages:
• good penetration
• maintains integrity of liquids (e.g. Lubricants)
due to the 100% humidity within the chamber.
Disadvantages:
• Non stainless steel metal items corrode
• may damage plastic and rubber items
Chemiclave
• Carbon steel and other corrosion-sensitive
burs, instruments, and pliers are said to be
sterilized without rust or corrosion.
• Expensive
Cold Sterilization
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Glutaraldehyde 2 to 3 % concentrations
Can kill bacterial spores in 6 to 10 hours
Broad spectrum action against vegetative microorganisms.
Toxic and corrosive
It is used to disinfect floors, surgical instruments, plastic
equipment, which can not be heat sterilized.
• Procedure:
• Use for no more than 2 weeks ( lost of activity)
Immerse object in liquid for several hours.
• Rinse with sterile water after end of procedure.
Radiation Sterilization
• Provides effective way of sterilization when using
non ionizing radiation in high doses (Gamma
radiation ).
• it is clean process
• dry process
• the object full exposure from all directions
RADIATION
Non Ionisizing radiation:
Types
Produced by Mode of action
Uses
Low energy UV lamps
DNA damage Infrared rays:
(Infrared and
Sterilization
ultraviolet rays)
of prepacked
items such as
syringes .
Ultraviolet rays:
Used for
disinfecting
operation
theatres
Comments
Use of UV
light
is limited by
penetration
and
hazardous.
RADIATION
Ionisizing radiation:
Types
Produced by
High energy
Cobalt-60
ionizing type
based
(Gamma rays instruments
and high
Energy
electrons such
As X-rays and
Cosmic rays)
Mode of action
DNA damage
Uses
Comments
Sterilization
They are
antibiotics,
expensive.
hormones
They are very
and other
effective due to
prepacked
high penetrative
disposable
power.
items such as
catheters, gloves,
syringes, infusion
sets, oils, animal
feeds, etc.
In summary
• Sterilization and disinfection are costly and
time consuming process
• However, it is an essential in all health care
facilities to avoid infection.
• It depends the material and users of
instrument.
• Staff should keep in mind that contaminated
instrument present risk to the sample as well
as the user himself.
Thank you