Heamo week 2 Intro to fluid Flashcards
What is the difference in Molarity and osmolarity
Osmolarity describes the number of molecules within a fluid including those that have dissociated
Molarity measures the moles of a solute
What is a Mole
This refers to the amount of substance in a solution
What is Tonicity
This is a measure of the osmotic pressure gradient between 2 solutions
What are the 3 catagories that tonicity can be broken into
Hypertonic - In a solution with a relative higher osmolarity than that dound in norm body cells and blood
Hypotonic - a solutoin with a relative lower osmolarity than found in body cells
isotonic - a solution with the same osmolarity as that found in norm body cells
Where does the water flow with each of these solutions
Osotonic - the osmotic gradient does not change dramatically so there is no drastic change in fluid
hypotinic - we dilute the intravascular space as a result there is a higher concentration in the intersitial fluid and water moves into the ICF
Hypertonic - there is a higher concentration in the intravascular space so water moves from the ICF into the intravascular space
What chatgerizes Crystalloid solutions
Contains molecules that quickly dissociate in solution
small particles that can easily move through cell membranes
Only short-live effect
Catagorized by tonicity
e.g.
Saline
5% dextrose in water
What chatagorizes Colloid solutions
Contain molecules that are too large to pass out of capillary
Prolonged effect
Draws fluid from ECF by oncotic pressure
Usually protiens
Typically hypertonic
E.g.
Albumin and gelatin
What is the difference between fluid resus and Fluid maintance
Fluid resus aims to rapidly restore intravascular volume through administration of large volumes of IV fluid to restore cardiac output & perfusion/ used for shock
Fluid maintenance/replacement aims to ensure normal hydration and electrolyte balance by giving measured doses of fluid, often infused with other nutrients over a longer period of time. used mainly in the hospital
Why would we want to give fluids
First priority: Give fluids to expand Intravascular volume allowing increased perfusion to tissues
Second priority: restore blood (oxygen-carrying capacity)
Third priority: normalize coagulation status
What are some complications of fluid overload
Overload of circulatory system, stress on the heart, liver, kidneys
Pulmonary oedema, acute kidney injury
Haemodilution - reduce the proportion of RBC, clotting factors & platlets
Acidosis - large volumes can induce hyperchloremic acidosis
Hypothermia
What is the 3:1 rule
This relates to the amount of solution that is lost with the administration of crystalloid fluid
It indicates that you should administer 3 times the amount of solution that the patient would have lost. e.g., 500ml of fluid lost, we could give 1500ml
How much fluid stays in the intravascular space
Roughly around 2/3 of the crystalloid fluid leaves the intravascular space
What can us in the prehospital setting help with the secondary properties
Hems/Heli - can sometimes administer blood
Ambo - can administer TXA, and follow fluid protocols properly (ensuring there is no haemodilution)
Ambo - can also ensure the pt is kept warm
What are the advantages/disadvantages of blood apose to fluids
Blood does not carry the same risk as that of fluids (increases oxygen carrying cabaility, nil acidosis)
The downside can be that they are $$$
What is the difference in a bolus and a infusion
A bolus is the push of a medication to a specific dose
An Infusion is where there is a slow, continuous administration
The method of administration can be determined from multiple things
Pharmacokinetics/dynamics, time for administration, desired effect, possible side -effects, specific indications
What is the drip rate calculation
What is a drip factor
This is the number of drops that make up 1 ml.
a Standard giving set is 20gtt/ml (20 drops makes up 1 ml)
