Administration of medications by injection into body tissues,
Purposes of parenteral medications:
· To get a rapid and systematic effect of the drug.
· To provide the needed effect even when the client is unconscious, unable to swallow due to neurological or surgical alterations affecting the throat and mouth or when the client is not cooperative.
· Assures that the total dosage will be administered and the same will be absorbed,
· Provides the only means of administered for medications that cannot be given orally.
· Medications that are rendered ineffective by the action of the digestive juices.eg :insulin
· Medications which cannot be retained in the intestine for a sufficient period for its absorption due to diarrhea, vomiting etc.
· When a drug irritating to the GI.
· To restore blood volume by replacing the fluid, e.g.: in shock
· To give nourishment when it cannot be taken by mouth
· To obtain a local effect at the site of injection,
· Local anesthetics such xylocaine
· Diagnostic purposes as in tuberculin test
· To test allergy to a drug. Eg; penicillin
Types of parenteral Therapies:
Subcutaneous/ hypodermal injection:medicine injected into the subcutaneous tissue. Eg: insulin
Intradermal: Medicines into the dermal layer of the skin.eg: penicillin
Intramuscular: Medicines injected into the muscles, eg: voveran
Intravenous: medicines introduced into a vein,
Intra arterial: medicine given into the arteries.
Intra osseous: drugs introduced into the bone marrow.
Intra peritoneal: medicines introduced into the peritoneal cavity
Intraspinal/ intrathecal: medicines injected into the spinal cavity
Venesection/ cut down: is the opening of a vein and a tube or a wide bore needle and giving medicines and fluid through it. Usually done in emergencies.
Intra cardiac: into the heart
Pleural: into the pleural cavity.
Intra articular: into a joint.
Infusion, Means a large quantity of fluid to be introduced into the body is as infusion. Usually given intravenously.
Transfusion is the of whole blood or plasma into a vein or artery.
An injection is an invasive procedure because it breaks the skin As such, it must be performed using proper aseptic technique to prevent risk of infection.
Types of syringes, needles, cannula & infusion sets:
Syringe is a device used for transfer of medication
· From storage container
· To administration container
· To patient
· System for maintenance of sterility
· System for measuring medication
· System for delivering medication
· System for prevention of needle sticks
Tip- which connects the needle
Barrel- outside part, which contains measurement calibrations. Acts as receptacle for medication
Plunger- which fits the inside the barrel and has a rubber tip. Used to pull or push medication into or out of barrel
(Nursing alert: the nurse must ensure that the syringe tip, inside of the barrel, shaft & rubber plunger tip & shaft of the needle are kept sterile).
There are several kinds of syringes, differing in size, shape, and material.
TYPES OF SYRINGES:
The three most commonly used types are the standard hypodermic syringe, the insulin syringe, and the syringe.
Size starts from 0.5 to 60 mL.
1 to 3 ml, adequate for SIC or injection
Larger sizes for IV medication
1. Hypodermic syringe
Comes in 2-, 2.5, 3-, and 5-mL Sizes.
The syringe may have two scales marked on it: minim and the milliliter. The milliliter scale is the one normally used; the minim scale is used for very small dosages.
2. Insulin syringe
An insulin syringe is similar to a hypodermic syringe, but the scale is specially designed for insulin: a 100-unit calibrated scale intended for use with U- 100 insulin.
This is the only syringe that should be used to administer insulin
These syringes frequently have a non-removable needle.
The correct choice of syringe is based on the amount of insulin required.
3. Tuberculin syringe
The tuberculin syringe was designed to administer tuberculin solution.
It is a narrow syringe, calibrated in tenths and hundredths of a milliliter (up to 1 mL) on one scale
Should be used for doses of 0.5ml or less
Also classified as:
Luer-Lok and Non-Luer-Lok.
A Luer-Lok syringe has a tip that requires the needle to be twisted onto it to avoid accidental removal of the needle
The non-Luer-Lok syringe has a smooth graduated tip, and needle are slipped onto it.
Pre-filled single-dose syringes (Pre-filled unit-dose systems)
These are available as:
· prefilled syringes ready for use or
· Prefilled sterile cartridges and needles that require the attachment of a reusable bolder before use.
Are made of stainless steel, and most are disposable.
Reusable needles (e.g., for special procedures) need to be sharpened periodically before resterilization because the points dull.
A dull or damaged needle should never be used.
Needles are available in different gauges — the smaller the number, the larger the gauge (inside diameter)
Length – long enough to penetrate the appropriate layers of tissue, needle has three parts, the hub, the shaft, and the bevel,
The hub is at one end of the needle and is the part that attaches to the syringe.
The shaft is the long slender stem of the needle that is beveled at one end to form a point,
Bevel- is the slanted pan at the tip of the shaft
The hollow bore of the needle shaft is known as the lumen.
Needle Size-is designated by LENGTH AND GAUGE
The length of a needle is measured in inches from the juncture of the hub and the shaft to the tip of the point. Needle lengths range from 1/2 inch to 3 inches; some special use needless are even longer.
The appropriate needle length is chosen according to the client’s muscle development, weight and the type of injection.
The gauge of a needle, used to designate the size of the lumen, ranges from 28 (the finest) to 18 (the largest).
For an adult requiring a subcutaneous injection, it is appropriate to use a needle of #24 to #26 gauge and 3/8 to 5/8 inch long,
Obese clients may require a 1-inch needle. For intramuscular injections, a longer needle (e.g., 1 to 1 1/2 inches) with a largest gauge (e,g; to #22 gauges) is used.
Factors to be considered in the selection of syringes and needles:
· The route ordered
· Viscosity of the medication solution
· Amount of medication to be administered
· Body size and the amount of fat
· The bevel should be sharp without any hooks
· Needle should fit tightly to the syringe, so that the pressure of the liquid will not blow off the
· Length and size of the needle should be appropriate to the site and the person
Needle less system:
Needle less devices or protected needles reduces the chance of accidental needle stick injuries and exposure to blood borne pathogens. It uses pressure to inject the medic on through the skin and is relatively pain- free.
Pre-filled cartridges: provides a single dose of medication, E.g. carpuject
Pre-filled syringes: syringes filled with medication, which can be used for more than one time.
Cannula is a tube that can be inserted into the small peripheral vein therapeutic purpose of medications, fluids and/or blood products,
· Scalp veins (Hollow-Needle Catheter)
· Designed to provide rapid venous access, for patient comfort during infusion.
· Butterfly wings facilitate for better and easy fixation.
· Super smooth, kink resistant tube.
· Color coded butterfly wings by size for easy identification.
· Sterile and Disposable
Intra-arterial catheters: designed to insert into arteries. E.g: radial artery
Central venous catheter: designed for central veins. E.g: Subclavian catheter
15-20 gtts = 1 mL, for giving large amounts of fluid
60 gtts = 1 mL, for restricting amounts of fluid
· To administer blood and blood components
· Has a filter to prevent clots from blood products from entering the body
· Approximately 20 drops — 1 ml
· With 200 micron filters and 18 G needle
· Kink resistant.
Volume control administration set (Buretrol)
· Delivers specific volumes of fluids
· It has got 150 ml containers that are attached below the infusion bag
· It is filled for prescribed amount prior to infusion
Electromechanical pump tubing which is specific for each pump.