ASEPSIS

of antiseptic surgery) studied prevention of wound infection(1865-1891).

contamination but does not necessarily destroy micro organisms. It is

necessary prerequisite for effective disinfection or sterilization.

ASEPSIS -Term used to describe methods which prevent contamination of wounds and other sites, by ensuring that only sterile object and fluids come into contact with them.

of viable microorganisms to an acceptable level but may not

inactive some viruses and bacterial spores.

STERLIZATION - it is the process of destruction or removal of all microorganisms from article, surface or medium, including spores.

to be completed-

Pre sterilization cleaning
Sterilization process
Aseptic storage

provide protective barrier for microorganisms and prevents its destruction.

There are

three methods for cleaning
-Manual
-Ultrasonic
-Mechanical washing

difficult to achieve.
Heavy duty gloves and glasses must be worn

to protect needle stick injury and to protect eye.
Material used for manual cleaning
-Soaps
-Detergents

which pass through a soap solution containing the instrument.

Used mainly for burs, bone files, bone cutter, artery forceps, saw etc.

detergent which removes debris from instrument.
Small instrument like burs,

blade are not suitable for this type of cleaning.

Dry b) Moist
Irradiation
CHEMICAL a) Gas b) Liquid antiseptics

- Dehydration and oxidation of organisms
- Protein denaturation
-

Toxic effects of elevated levels of electrolytes

do not get damaged by high temp. such as laboratory

glass, instruments with sharp cutting edges, scissors, clamps

two factors are achieved throughout the load.

the effective means of sterilization, because of its
1. High penetrating

capacity.
2. It gives of large amount of heat to surface with which it comes in contact.
3. To achieve sterility, a holding time of at least 30 minutes at 120 °C or 20 minutes at 132 °C at 1,1 above atmospheric pressure is required.

designed to melt only after being subjected to relevant holding

time.
Chemical indicator- Strips or tapes that change color once the correct conditions have been met.
Bacteriological test – detection of bacterial clumps on the instrument after its streilization

gamma rays, and high speed electrons .
Non-ionizing radiation, e.g. ultraviolet

light, and infrared light.
These forms of radiation can be used to kill or inactivate microorganisms.

and other vital constituents.
They have high penetration power.
There is no

appreciable increase in temperature, thus referred to as cold sterilization.
Commercial plants use gamma radiation for sterilizing plastics, syringes, swabs, catheters etc.

for sterilization:-
A. Ultraviolet -
Short range UV(UVC) is considered “germicidal UV”.
UV

will destroy micro-organismal DNA.
Used mainly for air purification and water purification in hospitals.
B. Infrared –
It is most commonly used to purify air, such as in the operating room. Infrared is effective, however, it has no penetrating ability.

that cannot be steam sterilized or sensitive to radiation.
Mechanism

of action: It destroys micro-organisms by alkylation and cause denaturation of nucleic acids of micro-organisms.
Plastics, rubber & photographic equipments can be sterilized by this method.
Also used for mass sterilization of disposable items, plastic syringes,needles,catheters,blades etc..

agents :Pot.Permanganate, Hydrogen Peroxide, Benzoyol Peroxide
Halogens : Iodine, Chlorine

Biguanide : Chlorhexidine
Alcohols : Ethanol, Isopropanol.
Aldehydes : Formaldehyde
Acids : Boric acid, acetic acid
Metallic salts ; Silver Nitrate, Zince Sulfate,

nonspecific and complex:
Cell membrane injury.
Coagulation and Denaturation.