Download PRACTICAL ON STERILIZATION METHODS, INJECTIONS &amp

Practical No : 01
PRACTICAL ON STERILIZATION METHODS, INJECTIONS &
TEMPERATURE MEASUREMENT
Temperature Measurement
Objectives
At the end of the practical, the student should be able to,
1. Explain how the human body maintains a core temperature at 37oC
i. Under normal conditions
ii. On exposure to cold environments
iii. With excess heat production.
2. Measure and record the body temperature accurately using a mercury
manometer.
3. Discuss the advantages and disadvantages of different sites of temperature
measurement.
4. Explain the clinical significance of body temperature measurement.
 Man is a homeothermic animal, i.e. he is capable of maintaining a constant body
temperature that is independent of the environmental temperature.
 A person's body temperature is the balance between heat production and heat loss
by his body.
 Man's body temperature is maintained in the following range : 97oF - 99oF
 Core Temperature is the temperature of the deep tissues of the body.
This remains constant usually within  1oF ( 0.6oC).
Core temperature ranges from 98oF to 98.6oF.
 Normal Body Temperature
37oC (36.3 - 37.1oC)
98.4oF (97.3 - 98.8oF)
Measurement of Temperature:
Equipment :
Mercury Manometer or
Thermistor (platinum head in the oesophagus) or
Thermocouple
Sites: Core Temperature
Surface Temperature -
Rectal, Oesophageal, Nasopharyngeal
Oral, Axillary, Groin
- Temperature is most often measured using a clinical thermometer (Mercury
Manometer)
- A special thermometer is available for taking the rectal temperature.
- Precautions o When taking oral temperature, hot or cold drinks should not be taken for at
least half an hour prior to recording the temperature.
o The subject should not breathe through his mouth when taking the oral
temperature.
o As it may take upto five minutes for final temperature equilibrium, the
thermometer should be kept in place for this amount of time, or till the
temperature recorded remains constant.
- The thermometer is disinfected with Savlon (the thermometer is kept with its bulb
dipped in Savlon solution)
- Before using, the bulb is wiped with a cotton swab soaked in sterile water, and
shaken until all the mercury within the capillary tube reaches the bulb (the point
below the constriction in the tube)
- Place the thermometer in the region where temperature is to be measured (mouth,
axilla etc.)
- Keep the thermometer in place,
 Sublingually - approx. 2 min.
 Axilla
- approx. 3 -5 min.
 Groin
- approx. 3 -5 min
 Rectum
- approx. 1 min
- After obtaining the reading, wipe the bulb with cotton wool and replace it in the
Savlon solution.
Reading :
Rectal Temperature =
Oral Temperature
=
Axillary Temperature =
Core Temperature
Core Temperature - 1oC
Core Temperature - 2oC
Advantages & Disadvantages :
Axillary Temperature
Advantages :
- Easy to measure
- No discomfort to patient
- Useful in small children
Disadvantages :
- Varies with
environmental
temperature
- Inaccurate in shock
states
Oral Temperature
Rectal Temperature
- Closer to core
temperature
- Useful in adults and
older children
- Less discomfort to
patient
- Easy to measure
- Very close to Core
Temperature
- Useful in shock states
- Children may bite on
bulb
- Affected by hot or cold
drinks
- Affected by breathing
through the mouth
- Aesthetically least
acceptable method
- Needs patient
cooperation
- Rigid tube can break in
situ
Heat production & Heat loss :
- The thermostat is the Hypothalamus
- Heat is produced by,
Basal Metabolism
Exercise / Emotion
Specific dynamic action of food
- Heat is lost via,
Radiation, Conduction (70%)
Vapourization of sweat (27%)
Respiratory passages (2%)
Urine and Faeces (1%)
Injections
Objectives :
At the end of the practical, the student should be able to,
1. Identify apparatus and instruments used to inject substances into the body.
2. Describe the routes of administering injections with examples.
3. Describe how to do a venepuncture.
Apparatus and Instruments
Nozzle
1. Hypodermic Syringe
-
Commonly used in clinical practice for collection of blood for
investigations and the administration if drugs.
Maybe glass or plastic
Glass syringes are non – disposable and have to be sterilized
(hot air oven)
Plastic syringes are sterilized chemically and can only be used
once. (available with needle).
A syringe has three main parts. The Piston, Barrel, and Nozzle.
Various sizes are available in order to collect varying amounts
of blood (1ml – 50 ml)
2. Needles (Disposable and non-disposable)
-
Needles are available in disposable and non – disposable
(metal) varieties
Disposable variety is safer as disease transmission can occur
from frequently used needles (HIV, Hep.B)
Needles have a “Gauge” which corresponds to its internal
diameter.
The gauge ranges from 18G (very large thick needles) to 27G
(very fine thin needles). – identified by a colour code
Therefore, the larger the ‘Gauge’, the finer the needle
A needle has two parts, a shank and a beveled edge (reduces
pain when puncturing the skin).
Barrel
Piston
Bevelled
Edge
Shank
3. Intravenous Cannula
-
-
Is used mainly to introduce fluids / drugs into the
body for over long periods of time.
Ideal for administering fluids continually (fluid
therapy).
Can also be used to obtain blood if needed repeatedly.
Consists of a needle, connected to a plastic hub (2way or 3-way), which also has a plastic cap (closing
cone), that can be closed when fluids etc. are not
being given, as well as a separate injection port. It also
has a stylet which helps in introducing the cannula
into a vein.
There are two flexible ‘wings’ that are used to anchor
the cannula to the skin.
Cannulae are also colour coded according to the
gauge.
They are disposable and are available sterilized with
Ethylene Oxide gas. Can be kept in situ for approx. 3
days.
Catheter with
steel needle
Flexible wings
Injection port
with protective
cap
Flashback
chamber
Closing cone
4. Sterile Lancet
- Is used to obtain capillary blood for certain investigations.
- They can be obtained in sterilized packs and are disposable.
- The lancet has a sharp edge, which is used to prick a subject’s
earlobe or finger.
- The first drop of blood is generally discarded.
- Ideal for blood grouping, PCV measurement etc.
5. Vacuum Syringes (Vacutainer)
- Is a type of syringe used in the withdrawal of blood,
where blood is drawn under a vacuum.
- Is a very safe and painless method.
- Especially useful in the collection of blood from
patients suspected of having HIV or Hep B
infection.
6. Tourniquet
- Is used to compress the blood vessels in a limb.
- Often used to obstruct the venous return from a limb to facilitate the withdrawal of
blood from a vein (in venepuncture).
- May vary in type from simple rubber or plastic tubing to Velcro bands and
pneumatic cuffs.
Routes of Administration
There are various routes of administration of substances into the body. The route
depends on the site of action and time of action required of a certain drug, substance
etc.
Methods,
1. Intradermal Injection
2. Subcutaneous Injection
3. Intramuscular Injection
4. Intravenous Injection
5. Intrathecal Injection
Intrademal Injection :
15o
Subcutaneous Injection :
Injection is made into the skin
The needle is kept almost parallel to the skin (approx. 15o)
and then inserted into it.
Prick only approx. 1 mm deep.
A thin needle (25G or 27G) is generally used.
Eg.
Manteaux Test
BCG vaccination
The substance is injected to the subcutaneous space.
The skin is pinched between the forefinger and thumb,
taking care not to pinch any blood vessels.
The needle is then introduced gently.
A short fine needle (25G) is used commonly.
Eg.
Insulin administration.
Intramuscular injection : This technique injects substances directly into a muscle.
Common sites are, the Deltoid Muscle and Upper outer
quadrant of the buttock.
The needle is introduced at an angle of 90o to the skin.
Following injection, pressure applied to the area to facilitate
drug dispersion and to avoid formation of a haematoma.
90o
A thicker, longer needle (21 – 22 G) is used as the drugs are
generally opaque and thick.
Eg.
Vitamins, Antibiotics, Tetanus toxoid
Intravenous Injection :
45o
Intrathecal Injection :
This technique injects substances directly into the vein.
The needle is introduced at an angle of approx. 30o - 45o
(see technique on venepuncture).
Veins in the cubital fossa and dorsum of the hand are used
Eg.
Antidotes
Employed to inject substances into the subarachnoid space.
Eg.
Obtaining CSF for investigation
Anaethetics
Venepuncture
Indications
:
To obtain venous blood samples for investigation
To transfuse intravenous drugs, fluids or blood
[In order to insert cannulae to distant sites (eg. Heart)]
Sites
:
Antecubital Fossa
Dorsum of the hand and wrist
[Femoral vein / Jugular vein]
Technique
:
-
-
Caution
:
Explain the procedure, obtain consent and reassure the patient
Wash hands thoroughly and wear gloves
Determine a suitable, preferably visible vein.
A tourniquet is applied proximally to the chosen site.
The vein is then made prominent by lightly tapping on it and
asking the patient to clench and unclench the fist of that arm.
Clean the area with surgical spirit
Insert the needle at an angle of 30 – 45o and feel for the loss of
resistance when the vein is entered into.
This will be indicated by a flash of blood into the hub of the
needle.
(In the case of injecting drugs, we should carefully observe the
flash of blood into the hub of the needle, and only then, inject the
substance into the vein.)
Withdraw blood slowly into the syringe taking care not to create
bubbles.
Remove the tourniquet and slowly withdraw the needle.
Apply a cotton swab to the area and elevate the arm or apply
pressure to prevent extravasation of blood into the surrounding
tissues.
Next, cap the needle and remove it from the syringe.
Put the blood into a suitable bottle to send for investigation.
Care should be taken to avoid spillage of possibly infected /
contaminated blood onto skin or any other surface
Sterilization and Disinfection
Objectives :
At the end of the practical, the student should be able to,
1. Identify the methods of sterilization and disinfection
2. List the practical applications of sterilization and disinfection in a hospital
setup.
Sterilization Is the destruction of the vegetative forms as well as spores of bacteria, viruses and
fungi.
Disinfection Is the destruction of only the vegetative forms of organisms. The spores remain
intact.
Methods of Sterilization
Physical Methods
Chemical Methods
Heat
Radiation
Gases
Dry heat
Micropore and
Millipore filters
Moist heat
Red Heat
Inoculating wires
Points of forceps etc.
Hot air oven
At 160oC for 1 hour
Used for heat resistant
glassware and metal
instruments
Infra red radiation
Scissors
Liquid
Filtration
Ethylene Oxide
Eg. Disposable
syringes
2% Gluteraldehyde
eg. Endoscopes
Use of ultraviolet rays.
For ionizing radiation, x-rays and
 rays are used.
Eg.
Heat unstable instruments
Prepacked disposable items
Plastic syringes
Catheters
Rubber equipment
Instruments that cannot withstand dry heat are
sterilized by this method.
Eg. Glassware, Syringes
At temperatures <100oC At temperatures of 100oC At temperatures > 100oC
Done by steaming under pressure (autoclave)
Pasteurization of milk
Steaming
121oC for 15 min. or
Bed linen sterilization
Boiling
134oC for 3 min.
Clothes
eg. Surgical instruments
Gloves
Dressings
Methods of Disinfection
Halogens
-
Used in treatment of water supplies
Cleaning walls, countertops and furniture
As skin disingectants (povidone iodine)
Eg. Tincture of Iodine 2.5%I2 or 2.5% KI in 90%
alcohol
Methylated spirits - Used as skin disinfectants
Eg. 70% Alcohol
Phenolic Derivatives - Eg.
Hibitane
Chlorhexidine
Lysol
Quaternary Ammonium Compounds
- Used as a pre-operative skin disinfectant in
combinatoion with other disinfectants.
- Not very effective alone
- Eg. Cetrimide
Soaps and Detergents
Oxidising Agents -
H2O2
KMnO4