Week 5 - IV Fluids: Crystalloids and Colloids Flashcards
What is the purpose of isotonic IV fluids? (2)
- expands only the ECF
- used frequently
What is the purpose of hypotonic IV fluids? (3)
- provides more water than electrolytes
- dilutes the ECF
- moves water into cells
What is the purpose of hypertonic IV fluids? (2)
- initially raises the osmolality of ECF and expands it (very dangerous)
- draws out fluid out of cells
Why can hypertonic IV fluids be dangerous? (3)
- used relatively infrequently in special circumstances
- need special monitoring
- chance for intravascular fluid volume excess and cellular dehydration
so probably good for someone w/ low amount of salt
What is the maintenance of IV fluids? When do we use IV as replacements?
maintenance - when oral intake is not adequate
Replacements - when losses have occurred
What are crystalloids?
- fluids for IV administration that supply water and electrolytes
What is the purpose of crystalloids? (2)
- help to maintain osmotic gradient between extravascular and intravascular compartments
- have a plasma volume-expanding capacity that is related to sodium concentration
What are crystalloid IV solutions composed of? (20
- fluid and electrolytes that are normally found in the body
- do not contain proteins (colloids)
In what situations would crystalloids be used? (6)
- better for treating dehydration than for expanding plasma volume
- Used as maintenance fluids
- to compensate for insensible fluid losses
- to replace fluids
- to manage specific fluid and electrolyte disturbances
- to promote urinary flow
What are the 3 types of crystalloid saline solutions?
- Normal Saline - NS 0.9%
- 0.45 Normal saline - 1/2 NS
- 3% saline
What are the characteristics of normal saline? (3)
- isotonic
- no calories
- slightly more NaCl than ECF
What does normal saline do to IV volume and ICF volume? (4)
- Expands IV volume
- preferred fluid for immediate response
- risk for fluid overload higher - Does not change ICF volume
What are characteristics of 0.45% Normal Saline? (3)
- Hypotonic
- Free water, Na, Cl-
- overuse may lead to cellular swelling (bc more salt in cell)
What does 0.45% NS promote?
- movement of water from ECF to ICF
What are the characteristics of 3% saline? (5)
- hypertonic
- must be administered slowly and with extreme caution
- may cause dangerous intravascular volume overload and pulmonary edema
What are the 3 types of crystalloid Dextrose Solutions?
- Dextrose 5% in water - D5W
- Dextrose 10% in water - D10W
- Dextrose 5% in 0.45% Normal Saline - D5 1/2 NS
What are the characteristics of D5W? (2) tonicity and calories
- isotonic (in the bag)
- Provides 170 kcal/L
What does D5W do in free water? ICF? (3)
Free water - becomes hypotonic
- moves into ICF
- caution with increased intracranial pressure
What are the characteristics of D10W? (4) ie. tonicity, calories, limitation
- hypertonic
- Provides 340 kcal/L
- free water
- upper limit of dextrose concentration that may be infused peripherally
What are the characteristics of Dextrose 5% in 0.45% Normal Saline (D5 1/2NS)? (2)
- provides calories
- prevents ketosis
hypertonic in bag, hypotonic in the body
Multiple Electrolyte solutions are a type of crystalloid IV solution. WHat are they? (3)
- lactated ringer’s (LR or RL)
- isotonic
- more similar to plasma than NS
What are multiple electrolyte solutions composed of? (3)
- Has less NA CL than NS
- Has, K, Ca, PO4, lactate (metabolized to HCO3)
it is electrolyte based
What is the purpose of using multiple electrolyte solutions? (2)
- expands ECF
- Common replacement fluid
What are colloid IV solutions? (3)
- aka plasma expanders
- protein substances that increase the colloidal osmotic pressure (COP) and move fluid from the interstitial compartment to the plasma compartment
- when the protein level in the blood falls, fluid shifts out of the blood vessels and into tissues
– colloids are used to treat this condition
What are the indications for colloids? (2)
- treat a wide variety of conditions
- are superior to crystalloids in plasma volume expansion but are more expensive
What are the contraindications of administering colloids? (3)
- known drug allergy
- hypervolemia
- severe electrolyte disturbance
Name some common colloids (5)
- Dextran 70
- Dextran 40
- Hetastarch
- 5% albumin
- 25% albumin
given when severe low albumin
