EXAM 2 - ELECTROLYTES Flashcards
What is an electrolyte?
substance that is electrically charged when in solution
Ca, K, Cl, Na, Mg
Which electrolytes are extracellular?
Na, proteins, Cl, bicarbonate
Which electrolytes are intracellular?
K, Mg, sulfate, proteins, phosphorus
What is sodium?
main ECF cation, governs osmolality and H2O distribution, water follows sodium, aids in acid-base balance, activates muscle & nerve cells, action potentials need Na in order to fire
What is hyponatremia?
-more water than sodium, sodium level in blood is too low
-when Na is below normal: 135
- osmolality of extracellular fluid is low = diluted
- rapid changes and drops in Na is more symptomatic than slow decline
What is beer potomania?
ETOH intake chronically lowers sodium due to low solute delivery to the kidneys
How does water intoxication relate to hyponatremia?
replacing losses with just water rather than electrolytes on a hot day when you are sweating
What are the two types of hyponatremia?
dilution hyponatremia
depletional hyponatremia
What is dilution hyponatremia?
total body sodium near normal, but total body water is increased
can be hypervolemic (edema) or euvolemic (no edema)
What is depletional hyponatremia?
hypovelmic, sodium lost, total body water reduced
What is the treatment for hyponatremia?
treat the underlying problem
fluid restriction if vol. overload, sodium replacement
What is the treatment for SEVERE hyponatremia?
ICU, bolus of 3% saline to start, telemetry monitoring, neuro checks Q 2-4 hrs
What is osmotic demyelination syndrome?
destruction of myelin sheath in brain stem and pons
cause: correcting hyponatremia too fast
What can osmotic demyelination syndrome result in?
central pontine myelinolysis
acute paralysis, dysphagia, dysarthria
NO KNOWN CURE
What is hypernatremia?
body fluids with more sodium than water
osmolality of extracellular fluid is high
Na level is upper limit of normal: 145
What can cause hypernatremia?
excess sodium: salt loading, medications, too much sodium admin (sodium bicarb, zosyn)
water losses, diarrhea, impaired thirst, uncontrolled DM, water deprivation, diuresis, tube feeding without free water
What are the clinical manifestations of hypernatremia?
thirst, dry mucous membranes, oliguria, confusion, lethargy, seizures, coma
What is the treatment for hypernatremia?
correction of water deficit, replace half in first 24 hours with D5W or free water
What is potassium?
main intracellular ion, regulates excitability of cells/cell electrical status, helps control intracellular osmolality
What causes hypokalemia?
decreased PO intake, stool output, normal loss or diuresis
What are clinical manifestations of hypokalemia?
A SIC WALT
alkalosis, shallow respirations, irritability, confusion/drowsiness, weakness/fatigue, arrhythmias, lethargy, thready pulse, decreased intestinal motility, N/V, ileum
What is the treatment for hypokalemia?
oral potassium chloride (KCL) - liquid, tabs, or powder but causes GI upset/bleeding so dilute with lots of water
IV- must be given slowly and diluted
Central Line 20 MEq/1 hr, IV 10 MEq
What is the treatment for hyperkalemia (sub-acute)?
stop supplemental K
limit K rich foods
cation exchange resin: sodium polystyrene sulfonate (oral/enema)
What is the treatment for hyperkalemia (emergency)?
push K into cells
glucose and insulin
NaHCO3 - temporary treatment
Dialysis
What is magnesium?
an intracellular cation stored in muscle and bone
What does magnesium help to maintain?
muscle and nerve function, cardiac rhythm, health and immune system, bone strength, blood pressure, electrolyte (K) and glucose levels
What are the causes of hypomagnesemia?
decreased intake (malnutrition, alcohol abuse), decreased absorption (Celiac disease, Crohn’s), increased need (pregnancy), increased losses
What are the clinical manifestations of hypomagnesemia?
serum level <1.7
tremors, weakness, apathy, delirium, coma, prolonged QT, widening of QRS, dysrhythimas, hypokalemia, abnormalities of calcium metabolism
What is the treatment for hypomagnesemia?
oral or IV mylanta, magnesium sulfate tables, IV magnesium sulfate
What are the causes and treatments for hypermagnesemia?
impaired kidney function - dialysis
excess mylanta use- eliminate use
What are clinical manifestations of hypermagnesemia?
N/V, neurological impairment (confusion/lethargy), hypotension, dysrhythmias, flushing, headaches
Where is calcium found?
found in bones and teeth
small amount ionized in blood, unbound and used for physiologic processes
What are causes of hypocalcemia?
decreased intake, hypoalbuminemia (calcium binds to albumin), increased loss
What are some clinical manifestations of hypocalcemia?
increased cell membrane excitability, trousseau signs, Chvostek sign
What is Trousseau sign?
use BP cuff to occlude blood flow, over 3 minutes see carpal spasm
What is Chvostek sign?
tap the facial nerve in front of of ear, elicit spasm or contraction: corner of mouth, nose, eye, and cheek muscles
What is the treatment for hypocalcemia?
oral replacement, vitamin D, IV replacement
What are the causes of hypercalcemia?
increased intake and reabsorption from bones, decreased loss of calcium
What are the symptoms of hyperparathyroidism?
nephrolithiasis (kidney stones), HTN, shorted QT, dehydration, somnolence, skeletal muscle weakness
What is the treatment of hypercalcemia?
treat underlying cause, symptom management, oral phosphate or calcitonin, increased mobility, IVF and diuretic
Where is phosphorus found in body?
bones and blood, inverse relationship with calcium
What is phosphorus for?
bone and teeth mineralization, cellular metabolism, acid base balance, cell membrane, helping muscles contract and recover, using and storing energy
What are the causes of hypophosphatemia?
excess loss, renal failure, hyperparathyroidism, decreased intake, cellular exchange in acid-base abnormality
What are the clinical manifestations of hypophosphatemia?
fatigue, muscle weakness, bone pain, bone fractures
What are the causes of hyperphosphatemia?
decreased excretion, hypoparathyroidism, increased intake, cellular exchange in acid-base abnormalities
What are the clinical manifestations of hyperphosphatemia?
muscle cramps, tetany (spasms), periorbital numbness or tingling
What is the treatment for hyperphosphatemia?
treat underlying cause, dialysis, aluminum hydroxide and aluminum carbonate (binds to phosphorus and increase excretion)
What does chloride do?
an extracellular ion that maintains acid base balance, works with sodium to maintain osmotic pressure/water balance
What can cause hyperchloremia?
dehydration, hypernatremia. diabetes insipidus (ADH), large infusion of sodium chloride
What are the symptoms of hyperchloremia?
muscle weakness, thirst, weakness, fatigue, dehydration
TREAT CAUSES
