lewis ch 16 (fluids and electrolytes) Flashcards
2/3 of body’s water is in the ____________ fluid
intracellular fluid
what is the best indicator of gain/loss of fluids
daily weights
what are the two prevalent electrolytes in the intracellular fluid
potassium
phosphate
what are the two prevalent electrolytes in the extracellular fluid
sodium
chloride
normal sodium range
135-145
normal potassium range
3.5-5
normal calcium range
9-10.5
normal phosphate range
3-4.5
normal magnesium rnage
1.3-2.1
normal bicarbonate range
22-26
normal chloride range
98-106
Movement of molecules across a
permeable membrane from high to
low concentration
diffusion
Uses carrier to move molecules
facilitated diffusion
• Process in which molecules move
against concentration gradient
• External energy (ATP) is required
for this process
active transport (ex: sodium potassium pump)
• Movement of water “down” concentration gradient • From a region of low solute concentration to one of high solute concentration • Across a semipermeable membrane
osmosis
fluids with the same osmolality as the
surrounding cells
isotonic
solutions that are less concentrated than in the cells (moves into cell, swells and possibly bursts)
hypotonic
fluids that are more concentrated than in the cells (moves out of cell, shrinks and possibly dies)
hypertonic
fluid in the interstitial space (second spacing)
edema
Primary organs for regulating fluid and electrolyte
balance
kidneys
normal urine output / hr
30 mL/hr
(from adrenal glands) glucocorticoid that has anti-inflammatory affects and increases blood glucose
cortisol
(from adrenal glands) mineralcorticoid that causes sodium and water retention
aldosterone
what does the heart release to decrease blood volume and pressure
natriuretic pepties (ANP and BNP)
what are causes of ECF volume deficit (5)
- insensible water loss (fever, stroke)
- hemorrhage
- GI losses (V/D, gastric suctioning)
- burns
- overuse of diuretics
what are causes of ECF volume excess (5)
- heart failure
- renal failure
- cushing syndrome
- long use of corticosteroids
- excess isotonic or hypotonic IV fluids
what are some manifestations of ECF volume deficit (5)
- thirst
- cold clammy skin
- decreased skin turgor and cap refill
- decreased urine output
- increased respiratory rate
what are some manifestations of ECF volume excess (7)
- peripheral edema
- JVD
- S3 heart sound
- increased bp
- polyuria
- dyspnea, crackles
- muscle spasms
what is ECF volume deficit called
hypovolemia
what is ECF volume excess called
hypervolemia
how to correct hypovolemia
isotonic solutions (0.9% NS or LR)
how to correct hypervolemia (3)
- diuretics
- fluid restriction
- restriction of sodium intake
Elevated serum sodium occurring with
inadequate water intake, excess water loss or
sodium gain
-causes cellular dehydration
hypernatremia
manifestations of hypernatremia (4)
- thirst
- alterations in LOC
- weakness
- muscle cramps
Results from loss of sodium-containing fluids
and/or from water excess (cellular edema- Na
shifts in the cell)
hyponatremia
manifestations of hyponatremia (4)
- difficulty concentrating, irritability
- increased bp
- N/V/D
- seizures
what are some causes of hyponatremia (5)
- vomiting/diarrhea
- GI suctioning
- inadequate salt intake
- diuretics
- hypertonic solutions (fluid shift from ICF to ECF)
how to treat hyponatremia (3)
fluid restriction
loop diuretic
hypertonic IV solution: 3% NaCl
how to treat hypernatremia (4)
- fluid replacement with sodium
- withhold diuretics
- give drugs that block ADH
- increase oral intake
food sources of potassium
fruits (apricot, avocado, banana, grapefruit, orange)
vegetables (beans, greens, potatoes)
other (pb, granola, milk)
high serum potassium
hyperkalemia
what can cause hyperkalemia (4)
- impaired renal excretion
- shift from ICF to ECF (acidosis, massive cell destruction)
- massive intake
- medications (digoxin, heparin, ACE inhibitors)
manifestations of hyperkalemia (4)
- cardiac dysrhythmias (peaked T waves, prolonged PR)
- cramping leg pain
- weak or paralyzed skeletal muscles
- abdominal cramping or diarrhea
how to treat hyperkalemia (3)
eliminate potassium intake
increase elimination potassium (diuretic, kayexelate)
administer calcium gluconate
med used to treat hyperkalemia
sodium polystyrene sulfate (kayexelate)
how does calcium gluconate help treat hyperkalemia
prevent cardiac dysrhythmias
low serum potassium
hypokalemia
causes of hypokalemia (5)
- respiratory alkalosis via hyperventilation
- metabolic alkalosis via diuretic use
- NG suctioning
- severe vomiting and diarrhea
- insulin therapy
manifestations of hypokalemia (5)
- cardiac: flattened T wave, prolonged QT, U wave
- skeletal muscle weakness
- decreased respirations
- anorexia and decreased GI motility
- hyperglycemia
low potassium can cause toxicity of what med
digoxin
how to treat hypokalemia
-potassium chloride supplements
calcium needs what vitamin in order to be absorbed
vitamin D
what two things balance calcium levels
parathyroid hormone
calcitonin
2 causes of hypercalcemia
- hyperparathyroidism
- malignancy
manifestations of hypercalcemia (5)
- fatigue
- hallucinations
- cardiac dysrhythmias
- bone pain and fractures
- polyuria, dehydration
how to treat hypercalcemia (3)
- increase hydration to 3,000-4,000 mL/day (can give isotonic saline IV)
- loop diuretics
- synthetic calcitonin
3 causes of hypocalcemia
- decreased production of parathyroid hormone
- multiple blood transfusions
- alkalosis
manifestations of hypocalcemia (5)
- positive trousseau’s or chvostek’s sign
- laryngeal stridor
- dysphagia
- tingling around mouth
- cardiac dysrhythmias (prolonged QT)
what is a positive trousseau’s sign
spasm of hand and wrist with blood pressure cuff
what is a positive chvostek’s sign
twitching of face when touching by ear
how to treat hypocalcemia (2)
- rebreathe into paper bag
- give calcium supplements
what electrolyte does calcium have a reciprocal relationship (see-saw) with
phosphate
4 causes of hyperphosphatemia
- acute kidney injury or chronic kidney disease
- chemotherapy
- excessive intake of phosphate or vitamin D
- hypoparathyroidism
manifestations of hyperphosphatemia (2)
- neuromuscular irritability and tetany
- calcified depositions in soft tissue
how to manage hyperphosphatemia (3)
- restrict dairy products
- loop diuretic
- hemodialysis
4 causes of hypophosphatemia
- malnourishment/malabsorption
- diarrhea
- use of antacids
- inadequate replacement during parental nutrition
4 manifestations of hypophosphatemia
- CNS depression
- rickets and osteomalacia
- respiratory and heart failure
- muscle weakness and pain
how to manage hypophosphatemia (3)
- oral supplements
- increased intake of dairy products
- IV administration of sodium or potassium phosphate
2 causes of hypermagnesemia
- increased magnesium intake when renal failure is present
- excessive IV magnesium admin
6 manifestations of hypermagnesemia
- lethargy
- urinary retention
- nausea and vomiting
- impaired reflexes
- muscle paralysis
- respiratory and cardiac arrest
how to manage hypermagnesemia (2)
- IV CaCl or calcium gluconate
- fluids and IV furosemide
5 causes of hypomagnesemia
- prolonged fasting/starvation
- diuretics
- prolonged parenteral nutrition without supplement
- fluid loss from GI tract
- chronic alcoholism
6 manifestations of hypomagnesemia
- hyperactive reflexes
- muscle cramps
- tremors
- seizures
- cardiac dysrhythmias
- hypocalcemia and hypokalemia
how to treat hypomagnesemia
- oral supplements
- increase dietary intake (nuts)
