Parentals Flashcards
What advantages are there to parentals?
For products that cannot be given orally When patient is unconscious When patient cannot tolerate oral medicine Patients who cannot swallow They give a predictable responce 100% bioavalibility Emergency use Rapid onset No issue of compliance
What is a parental?
A sterile preparation intended for administration by injection,infusion or implantation in the body.
What requirements must be met in parental?
Has to be completely sterile and free from viable microorganisms as it doe not go through intestinal system and skips bodies defences
All materials used must already be sterile
Be free from particles, pyrogens and endotoxins
Prepared in. Way as to minimise contamination during preparation, storage and use.
What is IC/ID injections?
Intracutaneous or intradermal injections just into the skin, between dermis and epidermis.
Small volume only 0.1/0.2 ml as there is poor vascular its
Use for diagnostic tests and vaccinations.
What is SC/hypodermic?
Subcutaneous injection just into subcutaneous tissue,under skin.
Up to 1ml
Not suitable for suspension or oily solutions as this causes pain
Vaccines, local anaesthetics, insulin, heparin
Good if patient has blood problem, as it’s not deep and should reduce bleeding
What is IM?
Intramuscular injection,directly into muscle.
Usually under 2ml but can be up to 4ml
Can use aqueous and oily solutions, and suspension.
This means they can be used for sustained release as the drug will slowly disperse from site of administration
Vaccines, antipsychotics - good for patients who cannot will not take medicine, get injections every 3 weeks etc.
What is IC?
Intracardiac
Directly into hear muscle or ventricles
Emergency use only
Adrenaline/isopreneline if no other route possible. Uk not licensed
What is IV?
Intravenous. From less than 1ml to 500ml as infusion Rapid body dispersion Mostly solutions but can be o/w emulsions, particle size tightly controlled Cannot use w/o emulsions.
What is IA?
Intra arterial
For immediate effect on peripheral organs
Cytotoxics such as methotrexate or radioactive materials
Can cause arterial spasms
Injected into site whee medicine is needed to act
What is intrasponal - intrathecal?
Less that 20ml
Into space surrounding spinal chord
Used for spinal anaesthetics,cytotoxic and treatment of bacterial meningitis
What is intraspinal intracisternal?
Into cisterns magna
Use to remove CSF - cerebral spinal fluid
Or to deliver antibiotics and dyes
What is intraspinal peridural?
Into space between dura mater and inside of vertebrae
Various locations along spinal column
Spinal anaesthetics - specific gravity must be controlled so that the medication affects correct location
IE epidural
What is intramural or infra articular.
Into either nurse between movable parts or synovial fluid.
Commonly used in shoulder elbow and knee
Inject solutions and suspensions
Corticosteroids
What is opthalmic injections are there?
Subconjunctival - close to eye but not in it
Intravireous - vitreous chamber
Intracameral - anterior chamber
Intraocular - posterior segment of the globe
Use to treat local infections or symptoms
Less than 1ml
What is intraosseous?
Into bones - replace bone marrow
What is intracerebral?
Into the brain, ie for brain tumour
What is intraperitoneal?
Into the peritoneum for dialysis solutions
How does pH affect parental products?
Needs to be tightly controlled.
Ideal - 7.4
IV must be 3-10.5 cause rapidly diluted
All others 4-9
Otherwise tissue necrosis is above 9, pain and phlebitis if under 3
Buffers used only if will not effect area it is injected into
Why is osmosis important in parentals?
If we inject a drug which cannot cross into cells, the liquid will rush out of the blood cells to try and create a balance over the membrane
As it is hard to measure osmotic pressure we use colligative properties IE blood plasma freezes at -.52 degrees, so if the medicine will freeze at this temperature, they are isotonic with the blood.
Must make medicines to be the same osmolality to minimise the unnecessary effects on the patient .
What is osmolality?
The mass of solute required to create an osmotic pressure equal to that seen when dissolving one mole of an ideal substance( does not dissociate) in 1kg of solvent
What happens if a blood cell comes into contact with a solution that is of higher osmolality and lower osmolality?
- greater osmolality than their contents,water passes out of the cell and they will shrink.
- lower osmolality, water will move into the cell and eventually burst.
What is isotonic?
This is when a solution is the same osmolality as the cell, so there is no flow of water.
What is hypotonic solution?
This is a solution which is lower in concentration that a cell that is placed into it. If placed around a cell, water will rush into the cell
What is a hyper tonic solution?
One that is more concentrated, when a cell is placed into it the water will rush out of the cell.
