Transcript - SlideBoom

DISINFECTION
Terminology
• Antiseptics: are disinfectants that can be
used on body surface such as the skin or
vaginal tract, to reduce the number of
normal flora & pathogenic contaminants.
• Bactericidal agents or germicide can kill
bacteria.
• Bacteriostatic agents: Only prevents the
multiplication of bacteria which may
however remain alive.
Free powerpoint template: www.brainybetty.com
2
Contd.
• Cleaning: Means removing soil & other
dirt & reducing the microbial burden,
making sterilization more effective.
• Decontamination: Refers to the process
of rendering an articles or area free of
danger from contamination including
microbial, chemical radiation & other
hazards.
Free powerpoint template: www.brainybetty.com
3
Definition
According to Ananthanarayan & Paniker’s
• Disinfection means the destruction or removal &
killing all pathogenic organism, or organisms
capable of giving rise of infection.
• Disinfectants are compounds that kill microorganism & may or may not kill spores, but are
not safe to apply to living tissues.
Free powerpoint template: www.brainybetty.com
4
Types of Disinfection
Disinfection
Concurrent
Terminal
Precurrent
Free powerpoint template: www.brainybetty.com
5
Concurrent Disinfection
• Disinfection as soon as pt. Is
discharged from the hospital.
• e.g. Disinfection of sputum,urine,
feces, clothing
Free powerpoint template: www.brainybetty.com
6
Terminal Disinfection
• Disinfection of a sick room and its contents
at the termination of a disease
• Disinfection after the patient has been
shifted from hospital or after his death.
e.g.. his bedding.
Free powerpoint template: www.brainybetty.com
7
Precurrent Disinfection
1. Precurrent is prophylactic disinfection,
that is , action taken prior to the onset of
infection. Examples are handwashing ,
chlorination.
Free powerpoint template: www.brainybetty.com
8
Disinfectant Characteristics
• Effective against all microorganism that is bacteria
including spores, virus, fungi & Protozoa.
• Active in presence of organic matter.
• Speedy action
• Effective in acid as well as alkaline media.
• High penetrating power.
• Stable.
• Not corrode metals.
• Not interfere with healing
• Not cause local Irritation
• Cheap & easily available.
Free powerpoint template: www.brainybetty.com
9
Factors that determine
potency of disinfectant
•
•
•
•
•
•
Conc. Of the substances.
Time of action
PH of the medium
Temperature.
Nature & number of the organism.
Others: hardness of water, humidity.
Free powerpoint template: www.brainybetty.com
10
Methods of Disinfection
• Moist Heat: Pasteurization, Boiling Water
& Low temperature (Subatmospheric)
steam
• Gases: Formaldehyde
• Chemical Agents: Halogens, Phenolics
Diguanides, Alcohol, Aldehydes
Free powerpoint template: www.brainybetty.com
11
Action of Chemical Agents
used for disinfection
• Protein coagulation
• Disruption of cell membrane
• Removal of free sulphydryl group
Free powerpoint template: www.brainybetty.com
12
Sterilization
• According to Ananthanarayan & Paniker’s
• Sterilization is defined as the process of killing all
micro-organism including bacteria, bacterial
spores, fungi & virus, such as Hepatitis & HIV.
OR
• It is process of destruction or complete removal
of all kinds of micro-organism including spores.
Free powerpoint template: www.brainybetty.com
13
Methods of Sterlisation
•
•
•
•
•
Physical Methods
Chemical Agents
Surface- active agents
Metallic salts
Gases: Ethylene oxide formaldehyde ,
betapropiolactone
Free powerpoint template: www.brainybetty.com
14
Physical Methods
•
1.
2.
•
1.
2.
•
Heat
Dry Heat
Moist Heat
Radiation
Non-ionizing radiation
Ionizing Radiation
Filtration
Free powerpoint template: www.brainybetty.com
15
Dry heat
• Flaming
• Incineration
• Hot air oven
Free powerpoint template: www.brainybetty.com
16
Flaming
• Direct exposure for a few
seconds by passing a few
times through the Bunsen
flame without allowing
them to become red hot
may be used for scalpels,
needles, glass slides,
cover slips, mouth of
culture tube, neck of
flasks, etc. But its efficacy
is not certain.
Free powerpoint template: www.brainybetty.com
17
Incineration
•
•
1.
2.
3.
4.
Disposal of contaminated material by
direct burning.
Method that is used for destroying
material such as
Soiled dressing
Bedding of patient
Pathological material
Animal carcases.
Free powerpoint template: www.brainybetty.com
18
Hot air oven
•
A holding period of
160oc for one hour is
used.
• It is two walled
chamber
1. Inner wall of copper
vessel.
2. Outer wall of asbestos
to reduce radiation of
heat.
Free powerpoint template: www.brainybetty.com
19
Direction for use
• The oven is heated by electricity, with heating
elements in the walls of the chamber.
• It must be fitted with a fan to ensure even
distribution of air & elimination of air pocket.
• It should not be overloaded.
• The material should be arrange so as to allow
free circulation of air.
• Glassware should be perfectly dry before being
placed in the oven.
Free powerpoint template: www.brainybetty.com
20
Moist Heat :
1. Temperature below 1000c
a) Pasteurization of milk: The milk is
heated by either 630c for 30 min. or 720c
for 15-20 sec followed by cooling quickly
to 1300c or lower.
Free powerpoint template: www.brainybetty.com
21
b) Inspissation
Inspissation is the
process used when
heating highprotein containing
media; for example
to enable recovery
of bacteria for
testing.
Inspissations
•
Heating at 80-85 c for 30 min. on 3 successive
days.
Principles
1.
2.
3.
4.
5.
FIRST EXPOSURE on DAY 1 KILL all vegetative
forms.
Spores which are not destroyed, would germinate to form
vegetative forms before the 2 exposure.
2 EXPOSURE on DAY 2 KILLS Newly formed
vegetative forms.
Spores if present, germinate till 3 rd exposure & would be
killed on third exposure
ON 3 RD DAY EXPOSURE ensure complete
Sterlisation.
Free powerpoint template: www.brainybetty.com
23
c. Water Bath
• Uses : For Sterlisation of serum or body
fluids containing coagulable protein.
• Method- heating for 1 hr. at 56ºC on
several days in water bath.
Free powerpoint template: www.brainybetty.com
24
d. Vaccine Bath.
• Uses : For inactivation of non-sporing
bacteria for preparation of vaccine.
• Method: Heating for 1 hr. at 60 c in
vaccine bath.
It is an apparatus, used in vaccine production. As vaccines
are very heat labile but inevitably need to be heated to some
extent, these devices are used. These are basically, water
baths, with a temperature set very low. A long time is taken to
sterilize vaccines by this method.
Free powerpoint template: www.brainybetty.com
25
2. Temperature around 100ºc
• Boiling
• Steaming
• Tyndallisation.
Free powerpoint template: www.brainybetty.com
26
Boiling
• Boiling at 1000c for 10-30 min kills almost
all vegetative bacteria but does not ensure
complete sterilization.
Free powerpoint template: www.brainybetty.com
27
Steaming
• Steaming at atmospheric pressure at
1000c is used to sterilize culture media.
• One exposure for 90 min. ensures
complete sterilization.
Free powerpoint template: www.brainybetty.com
28
Tyndallisation
• Method used to destroy bacteria and endospores and agar.
• The jars fitted with a filter disc or a polyfill lid filter are boiled
or steamed at 212°F (100°C) for 30 min in a pot with lid, three
days in a row.
• The jars are kept warm, around 30°C(but room temperature
will work too), to allow the remaining endospores to germinate.
• The basic principle behind this method is that any resistant
endospores will germinate after the first heating and therefore
be susceptible to killing during the second and third heating..
Free powerpoint template: www.brainybetty.com
29
Timetable of the tyndallization (=fractional sterilisation)
process
1) Steam heating to 100 °C for 30 min
Vegetative cells are destroyed but endospores survive
2) Incubate at 30°C-37°C overnight
Most bacterial endospores germinate
3) Second heat treatment, 100 °C, 30 min
Germinated endospores are killed.
4) Second incubation at 30°C-37 °C overnight
Remaining endospores germinate
5) Third heat treatment, 100 °C, 60 min
Last remaining germinated endospores are killed
Free powerpoint template: www.brainybetty.com
30
Autoclave
•
Free powerpoint template: www.brainybetty.com
31
Autoclave
• An autoclave is an instrument used to sterilize
equipment and supplies by subjecting them to
high pressure saturated steam at 121°C for
around 15–20 minutes depending on the size
of the load and the contents.
• It was invented by Charles Chamberland in
1879.
Free powerpoint template: www.brainybetty.com
32
Principles
• Water boils at 100ºc when its vapor
pressure is same as that of atmospheric
pressure.
• When the vapor pressure increases the
temp. at which water boils also increases.
• The steam under pressure has greater
penetrating power.
Free powerpoint template: www.brainybetty.com
33
Direction for use
•
•
•
•
•
•
•
•
•
•
Sufficient water is put in Cylinder.
Articles to be placed on a platform.
The lid is closed properly & screws are tightened.
The safety valve is adjusted to the required pressure.
Heating is started with steam tap kept open to displace air
inside.
Water pressure boils at 121ºc.
This pressure is maintained for 15 min.
Then autoclaving I turned off.
Steam tap is opened slowly to allow the air to enter inside.
Then lid is opened & material is taken out.
Free powerpoint template: www.brainybetty.com
34
Uses of Autoclaving
Which are not damaged by steam.
• Solid & liquid media.
• Saline solution.
• Laboratory coats
• Swabs, syringes & needles
• Surgical instruments
• Dressing
• Laboratory wares
• Pharmaceutical products.
Free powerpoint template: www.brainybetty.com
35
Radiation
• There are 2 types of radiation
1. Non-ionizing radiation
2. Ionizing Radiation.
Free powerpoint template: www.brainybetty.com
36
Non-ionizing radiation
• Sources:
1. Component of sunlight
2. UV Lamps.
Free powerpoint template: www.brainybetty.com
37
Ionizing Radiation
•
•
•
•
Includes Gamma rays, beta rays & X rays.
They are highly lethal to DNA.
High penetrating power.
Gamma & beta rays are used for plastic
syringes, swabs, culture plates, catheters,
oils & greases.
Free powerpoint template: www.brainybetty.com
38
Filteration
• Filters are used for removal of microorganism from the fluids or liquids.
Free powerpoint template: www.brainybetty.com
39
Types of filters.
•
•
•
•
Candle filter
Asbestos filter.
Sintered glass filter
Membrane filter.
Free powerpoint template: www.brainybetty.com
40
Candle filter
• Used for purification of water on large
scale.
ASBESTOS CANDLE
• Composed of asbestos fibers.
• Disposable
Free powerpoint template: www.brainybetty.com
41
• Candle filter
• Asbestos filter
Free powerpoint template: www.brainybetty.com
42
Sintered Glass filter
• Composed of finely powdered glass
particles.
• They have low absorptive property.
• They can be cleaned easily.
• They are expensive.
Free powerpoint template: www.brainybetty.com
43
Membrane filters.
• Composed of cellulose esters and are
called Millipore.
• Water purification & analysis.
• Sterlisation & sterility testing
• Preparation of solution for parenteral
use.
Free powerpoint template: www.brainybetty.com
44
Pictures.
• Sintered glass filter
• Membrane filters
Free powerpoint template: www.brainybetty.com
45
THANK
UUUUUUUUU
Free powerpoint template: www.brainybetty.com
46