Exam 1: Fluid and Electrolytes imbalance Flashcards
Total body fluid depends on what 4 things
muscle mass
electrolytes
body fat
age
In the newborn infant more than half of total body fluid is ________
extracellular
For adults what is the % of TBW for each:
Intracellular
Extracellular
Interstitial
Intravascular
Transcellular
66%
34%: extracellular
– 75%
–25%
–1%
Serum levels indicate _______ concentration
extracellular
Osmolality/osmolarity
measurement of number of particles in a solution or the concentration of the solution
Normal osmolarity
275-290 mOsm/kg
Osmolality and osmolarity are regulated by
ADH release
Osmolality (concentration of solutes in water) exert osmotic pressure causing…
osmosis
_____: measurement of osmotic pressure of a solution–osmalality
tonicity
Isotonic
same osmolality of serum blood
hypertonic
osmolality higher than that of serum, causing ICF to shrink
hypotonic
osmolality lower than that of serum, causing ICF to swell
__________ pressure: pulling pressure exerted by proteins colloids in the blood
colloid oncotic pressure
Colloid oncotic pressure ____ or ____ fluid from the interstitial
pulls/absorbs
_________ pressure: created by the weight of fluid pressing against the wall of blood vessels
hydrostatic
hydrostatic pressure forces molecules through a
capillary membrane
_________ movement of water and solutes from highly hydrostatic pressure to low hydrostatic pressure
filtration
What factors regulate water in the body
ADH and thirst
ADH is stimulated by ____________ or ________ and cause increased water resorption in the kidney tubules
decreased blood volume or increased serum osmolality
What is ANP
amino acid peptide synthesized, stored, and released by atria cells
What does ANP do to blood pressure
decreases blood pressure and volume
T/F isotonic fluid deficit (hypovolemia) has a proportional loss of both sodium and water from ICF?
yes but there will be no change in osmolality –> no fluid shift
isotonic fluid excess can cause ECF to become
hypotonic
What is the most predominant electrolyte in the ECF??
sodium
What is sodiums normal level
135 to 145
sodium imbalance is usually associated with parallel changes in water ____ or _____
loss or gain
Sodium is important for what
transmission of nerve impulses and muscle contraction
Hypernatremia etiology
water loss is greater than sodium loss
Hypernatremia clinical presentation
dehydration, thirst, dry mucous membranes, decrease LOC, seizures
Hypernatremia treatment
free water boluses
hypotonic fluid replacement
treat cause
if due to excessive Na, diuretics
Hyponatremia etiology
excessvie water intake (SIADH
hyponatremia clinical presentation
s/s fluid overload, neuro impairment, changes in LOC, muscle weakness, seizures
Sodium loss can be caused by
GI loss, diuretics, diaphoresis
Treatment for hyponatremia
excessive water: fluid restrict, diuretics
sodium deficits: replace sodium
What is the main cation in ICF
potassium
What is potassium responsible for
transmission of nerve fibers
Contraction of skeletal, smooth, and cardiac muscles
Hyperkalemia treatment
glucose and insulin
sodium bicarb
calcium chloride
kayexalate (not fast)
sorbitol
treat cause (e.g. dialysis)
S/S of hyperkalemia
GI
CNS
Muscles
Cardiac
Urine
GI: N/V/diarrhea
CNS: numbness, paresthesias
Muscles: irritability (early) and weakness (late) –> flaccid paralysis
Cardiac: ventricular fibrillation and cardiac arrest
Urine: oliguria –> anuria
S/S of hypokalemia
GI
CNS
Muscles
Cardiac
Kidneys
GI: anorexia, N/V, abdominal distention –> paralytic ileus
CNS: lethargy, diminished deep tendon reflex, confusion, mental depression
Muscles: weakness –> flaccid paralysis, weakened respiratory muscles –> respiratory arrest
Cardiovascular system: decrease in standing BP, ECG changes, Cardiac arrest, Myocardial damage
Kidney’s: decreased capacity to concentrate waste –> water loss –> thirst –> kidney damage
Treatment of hypokalemia
Potassium replacement and treat the cause
Normal calcium levels
9.0-10.2 mg/dL
What 3 things regulate Ca
PTH
Vitamin D
Calcitonin
What is calcium responsible for doing
transmission of nerve impulses
contraction of cardiac muscles
formation of bones and teeth
coagulation process
Calcium is bound to _____ so if that is low, calcium is generally low as well
albumin
S/S of hypocalcemia
GI
CNS
Muscles
Cardiac
Bones
GI increased peristalsis –> N/V/D
CNS: tingling –> convulsions
Muscles: spasms –> tetany
Cardiac: dysrhythmias –> cardiac arrest
Bones: osteoporosis
What can cause hypocalcemia
decreased ionized calcium: large tranfussion with citrated blood
excess loss: kidney disease, draining fistulas
inadequate intake
decreased GI and bone absorption: decreased vit d, PTH; increased mg, calcitonin
What are the treatments for hypocalcemia
calcium replacement: IV 10% calcium gluconate or cholride slowly
Vitamin D replacement
oral calcium for chronic
treat cause
What are 2 signs of low calcium
trousseau sign
chvostek sign
Trousseau sign:
how can you check for it
what is a positive signs of it
you can check while monitoring vital signs –> triggered by placing a BP cuff on an arm and inflating it to a pressure greater than systolic BP for 2 to 3 minutes
If you have it, your arm muscles will activate involuntarily and have flexion of the wrist, thumb, and joints with extension of the fingers
Chvostek signs
abnormal twitching of muscles that are activated by the facial nerve –> when it is tapped in front of the ear, the muscles on the same side will contract
What are causes of hypercalemia
loss from bones: metastases, multiple myeloma, immobilization
excess intake
increase in factors causing mobilization from bone: increased PTH, Vit D
S/S of hypercalcemia
Kidneys
CNS
Muscles
Cardiac
Bones
Kidneys: stones –> damage
CNS: decreased reflex –> lethargy –> coma
Bones: pain –> osteoporosis –> fractures
muscles: fatigue –> decreased GI motility
Cardiac: depressed activity –> dysrhythmias –> cardiac arrest
What is the treatment for hypercalcemia
Normal saline infusions
corticosteroids to decrease GI absorption
mithramycin
phosphate administration
treat cause
What does your body look like with hypercalcemia?
slow movements
What is a normal magnesium level
1.3-2.2
What does magnesium do
contract myocardium and influence transportation of Na/K across cells
S/S hypomagnesemia
mental changes
CNS
Muscles
Cardiac
mental: agitation, depression, confusion
CNS: convulsions, paresthesias, tremor, ataxia
Muscles: cramps, spasticity, tetany
Cardiac: tachy, hypotension, dysrhytmias
Causes of hypomagnesemia
decreased in
impaired absorption: alcohol withdrawal, hypercalcemia, diarrhea
Excessive excretion: increased aldosterone, conditions with large losses of urine
Treatment of hypomagnesemia
magnesium replacement
treat the cause (hypomagnesemia caused dig toxicity)
What is a rule of thumb when replacing K and Mg
don’t replace potassium until you replace magnesium first
What are causes of hypermagnesemia
increased in
decreased out: renal failure, adrenocortical insufficiency
S/S hypermagnesemia
Muscle
CNS
Cardaic
Muscle: weakness, paralysis, hyporeflexia, resp paralysis
CNS: drowsiness, confusion, coma
Cardaic: hypotension, flushing, T-wave changes, brady
Treatment of hypermagnesemia
fluids
dialysis
calcium gluconate
treat underlying cause