N368 Final Fluids and Electrolytes Flashcards
The most important regulator of fluid is:
thirst
Thirst center is located in:
the hypothalmus
What are the primary regular of fluid output?
kidneys
Mechanisms that influence fluid output
Renin-angiotensin-system
Aldosterone
Antidiuretic hormone
Aldosterone causes the conservation of:
sodium, and excretion of potassium
Increased sodium leads to…
increased water and increased BP
Drugs that interfere with aldosterone production are used as:
antihypertensives
Osmolality
absolute concentration of osmotic solution
Greatest contributor of osmolality is:
sodium
Sodium controlled by the hormone
aldosterone
Tonicity
relative concentration of intravenous fluid
Isotonic IV fluid
No fluid shift
Used to treat fluid loss due to vomit, diarrhea, or surgical procedures, ESPECIALLY WHEN BP IS LOW
Hypertonic IV fluids
Water moves from interstitial space to plasma
What is hypertonic IV fluids used to relieve?
cellular edema, especially cerebral edema
Hypotonic intravenous fluid
Water moves from plasma to interstitial space
Hypotonic is used to treat
dehydration when BP is normal
Fluid deficit can cause
dehydration or shock
Fluid deficit can be treated with
oral or intravenous fluids
Fluid excess can be treated with
diuretics
When replacing fluids and electrolytes you use:
crystalloids and colloids
Causes of water and electrolyte loss:
Volume loss in intravascular space due to lack of fluid volume
Volume loss in intravascular space due to transfer of fluid into third space
Examples of volume loss due to transfer of fluid into third space
kidney failure and liver failure
Examples of volume loss due to lack of fluid volume
NAME?
Treatment of volume loss due to transfer of fluid into third space
Crystalloids as first drug of choice
Treatment of volume loss due to transfer of fluid into third space
Colloids
Colloid helps reduce:
3rd space accumulation, reduces volume loss in intravascular space
How are crystalloids different from colloids?
Crystalloids are capable of leaving plasma and moving to interstitial spaces and intracellular fluid
Types of crystalloids
Isotonic
Hypertonic
Hypotonic
Crystalloids primary use
to replace fluids and promote urine output
What type of crystalloid is used to treat dehydration with LOW BP?
Isotonic solution (ex. normal saline, because the priority is to treat the low BP)
What type crystalloid is used to treat dehydration with NORMAL BP?
Hypotonic solution
What type of crystalloid is used to treat hypernatremia with cellular dehydration?
Hypotonic solution
Colloid molecules
large molecule solutes so they cannot easily cross capillary membrane
Colloid mechanism of action
draw water from intracellular fluid and interstitial spaces into plasma
What do colloids do?
NAME?
Colloid primary use
fluid replacement with hypovolemic shock from hemorrhage, surgery, severe burns
Adverse effects of colloids
Hypersensitivity reactions
Fluid overload
Hypertension
Nursing considerations when using colloids
Monitor fluid volume status
Assess neurological status and urinary output
Teach client to report hypersensitivity or fluid volume overload
Electrolytes are essential to:
nerve conduction, membrane permeability, water balance, and other critical body functions
Major electrolytes
Calcium Magnesium Phosphate Potassium Sodium
What stimulates adrenal gland which releases aldosterone?
Lack of sodium of increase of potassium
What happens when aldosterone increases sodium re absorption?
Increase in potassium excretion so increase in sodium in plasma
What is considered hypernatremia?
Sodium level above 145 mEq/L
What is the most common cause of hypernatremia?
kidney disease
Normovolemic hypernatremia
Caused by excessive sodium intake, no water changes
Hypervolemic hypernatremia
Caused by decreased excretion (ex. kidney disease)
Hypovolemic hypernatremia
Caused by high net-water loss
not enough water intake or excessive water loss due to diarrhea, fever, burns, ect.
Signs and symptoms of hypernatremia
THIRST, fatigue, muscle twitching
Treatment of hypernatremia caused by excessive sodium intake
Low salt diet
Treatment of hypernatremia due to dehydration
hypovolemic hypernatremia
give hypotonic solution