Fluid Types Flashcards
What is osmolarity?
describes the concentration of dissolved particles (or solutes)
Hypotonic solutes have a (higher, lower, same) osmolarity than the blood.
lower
With hypotonic solutions, Osmosis causes water to move from _________ space to __________ space.
extracellular, intracellular (cell swells)
What do hypotonic fluids do in relation to cells?
They dilute extracellular space and replenish the inside of the cell.
A patient has hypernatremia. What type of fluids should you give and why?
Hypotonic because it will dilute the concentration of solutes.
Hypotonic fluids can provide free water to help the _________ excrete waste and prevent ______________.
kidneys, dehydration
Examples of hypotonic fluids
half normal saline
anything less than half normal saline
D5W
What is special about D5W?
It starts out as an isotonic fluid but will become hypotonic within the body.
Hypotonic fluids can lead to brain swelling. Why?
Because fluid is moving from the ECF to the ICF which leads to cell swelling.
What should you monitor for when giving hypotonic fluids?
mental status changes
hypotension
hypovolemia
hyponatremia
What type of patients are most sensitive to hypotonic fluids and why?
Patients who are fluid sensitive (like heart or renal failure patients) because they cannot handle the extra water.
Hypertonic solutions have a (higher, lower, same) osmolarity than the blood.
higher
With hypertonic fluids, osmosis will cause water to leave ___________ space.
intracellular (cell shrinks)
Hypertonic fluids will (expand, shrink) extracellular space.
expand
What kind of patients would benefit from hypertonic fluids?
hyponatremic
cerebral edema (brain swelling)
Examples of hypertonic solutions
3% saline
D10W
D5NS
D5 1/2 NS
What are 2 big reasons why should I use caution when administering hypertonic fluids?
can overload the extracellular space leading to pulmonary edema
can cause hypernatremia
Isotonic solutes have a (higher, lower, same) osmolarity than the blood.
same
Do isotonic solutions affect the size of the cell? Why or why not?
No because there is an equal transfer of water between the ECF and ICF.
What will isotonic solutions expand?
the extracellular fluid volume (plasma)
What are some reasons why you would want to administer isotonic fluids?
fluid loss in extracellular space
vomiting
diarrhea (need Na and Cl back)
hypovolemic shock
burns
prior surgery (will lose ECF)
Examples of isotonic fluids
normal saline
LR
D5W (starts as isotonic but will change to hypotonic in the body)
What does NS replace?
water, sodium, and chloride
What is the only solution that can be administered with blood?
NS
What should I monitor for when giving isotonic fluids?
- fluid overload (esp in those with heart or kidney failure)
- BP
- breathing/lung sounds
- edema in extremities
What does D5W replace?
water and dextrose
What fluid would help with hypernatremia but would NOT be used for fluid resuscitation?
D5W
What fluid starts out as isotonic but changes to hypotonic and why?
D5W because the dextrose is metabolized, so only water is left. This is hypotonic (has low osmolarity).
What is in LR?
water, K, Na, Cl, Cal, and Lactate
What does the lactate in LR help to increase blood pH?
lactate will convert to bicarb thus increasing your blood pH
Who would you not want to give LR to?
a patient with liver disease (liver convert lactate to bicarb) or lactic acidosis (already has a high amount of lactate present)
Name some colloid solutions
Natural - albumin, FFP (Frash Frozen Plasma)
Synthetic - dextran, hydroxyethyl starches (HES), and gelatin
Describe colloid solutions
- large molecules that stay in intravascular space longer
- fast at expanding the intravascular space by pulling water into intravascular space
- amount administered = amount lost
What type of patient would you want to have colloid solutions?
patients with hypovolemic shock, severe burns, or severe bleeding, or low albumin levels
Name crystalloid solutions
hypotonic, hypertonic, and isotonic solutions
Describe crystalloid solutions
- small molecules that don’t stay long in intravascular space
- high amount of fluids needed = amount lost
Risks of colloid solutions
- allergic reaction
- coagulation problems
- high cost
Risks of crystalloid solutions
- edema/fluid overload
__________ pressure pulls water through the capillary wall
Oncotic
___________ pressure pushes water across the capillary wall.
Hydrostatic
Hydrostatic pressure is created by the _________ _________.
heart’s contractions
Hydrostatic pressure is __________ at the arterial end of the capillary
highest
Hydrostatic pressure is __________ at the venous end of the capillary
lowest
What is ANP - Atrial Natriuretic Peptide?
a hormone released by heart cells due to atrial wall stretching
What is BNP - Brain Natriuretic Peptide?
A hormone released by heart cells due to ventricle wall stretching
What do ANP and BNP do in relation to the RAAS?
they work against angiotensin II and stop the effects of aldosterone, ADH, and renin. Which helps to prevent fluid volume overload
