Electrolytes Flashcards
what is a major cation in the extracellular space?
sodium (test question)
hyponutremia
low sodium
what does sodium content indicate?
balance between dietary sodium intake and renal excretion
when do you lose sodium?
when you sweat
what are critical sodium values?
<160
what does aldosterone do?
retains sodium (reabsorbs)-distal tubule, excretes potassium
water follows what?
sodium
who is best buds with sodium?
chloride
what does ADH do?
released from posterior pituitary
holds water in
-alcohol inhibits ADH
when will ADH be released?
increased osmotic gradient
decreased vasopressure
what is the recommended Na intake?
1500mg/day (test question)
fatigue, confusion, muscle twitches and death are symptoms for what?
hypernatremia
nausea, seizures, coma and death are symptoms for what?
hyponatremia
what type of tube will sodium serum be drawn into?
red or green
what is the major intracellular cation?
potassium
what are critical K values?
6.5
what foods contain potassium?
tomatoes, potatoes, bananas
what controls K levels?
aldosterone (increase renal loss of potassium)
how does acid base balance influence serum potassium?
in alkalosis = K goes in, hydrogen goes out (makes serum more acidotic)
in acidosis = K goes out and H goes in (makes serum more alkalotic)
how is serum K collected?
red or green top
weakness, paralysis, hyporeflexia, ileus and cardiac dysarhythmia are symptoms of what?
hypokalemia
irritiability, nausea, vomiting, intestinal colic and diarrhea are symptoms of what?
hyperkalemia
what is the major extracellular anion?
chloride (follows sodium)
how does chloride compensate for acid/base imbalance?
chloride goes in while bicarb comes out (makes serum alkalotic)
chlorides goes out while bicarb comes in (makes serum acidotic)
what top tube do you draw chloride in?
red or green
hyperchloridemia
increase serum chloride
when sodium levels are off, what’s the problem?
water, water, water
where does venous bicarb level come from?
CO2
breakdown of carbonic acid gives CO2 and bicarb
total CO2 is in the veins
what are critical values of bicarb?
<6
normal is 23-30
how do you collect bicarb?
red or green top
when do you stop making bone?
30 yo
what do you need to absorb calcium?
vitamin D
how does PTH work?
triggered by low Ca serum
- absorb Ca from GI
- absorb Ca from kidneys
- resorb Ca from bone (break down bone)
which type of calcium is “active”
ionized Ca (free)
which type of calcium is “bound”
bound to protein
how do you correct the total calcium level?
0.8 ( 4.0-serum albumin) + total calcium
= corrected calcium
what do you have to do if you want to know the ionized Ca?
order an ionized Ca test
what are the most common causes of hypercalcemia?
- hyperparathyroidism
- cancer
- excessive vitamin D intake
anorexia, N/V, somnolence, confusion and constipation are symptoms of what?
hypercalcemia
nervousness, tetany and excitability are symptoms of what/
hypocalcemia
who is buddies with calcium?
phosphorus
when phosphorus is normally high,
calcium is usually low
what happens when phosphorus gets low?
they don’t breathe (need atp)
where is phosphorus absorbed?
in small bowel
what do kidneys do with phosphorus?
excrete (when they fail, phosphorus levels go up)
why is calcium low in kidney failure?
you don’t have active vitamin D
what is critical value of phosphorus?
<1 mg/dl
what tube is used to collect phosphorus?
red top
where is phosphorus stored?
intracellular
how does antacid work to decrease phosphorus?
binds with phosphorus in food and is excreted through GI
where is magnesium found in the body?
intracellularly
how is magnesium removed from the body?
kidneys
which tube is magnesium collected in?
red or green top
