calcium Flashcards
What is the function of calcium?
propagation of NM activity, regulation of endocrine functions, blood coagulation, bone and tooth metabolism
How is calcium regulated?
by the PTH, serum phosphate, vitamin D, and by target organs
What is the normal sodium total calcium?
8.5-10.5
What is the normal sodium ionized calcium level?
4.6-5.2
How much of calcium is distributed to the bone?
98-99% in the bone
How much is in the serum?
<0.5%
How much is protein bound?
46%
What is 80% of calcium bound to?
albumin
Is calcium active or inactive when bound to albumin?
inactive
What is the physiologically active form of calcium?
ionized calcium (unbound)
When should you correct for albumin?
What else do you have to correct for?
when albumin levels are less than 4
changes in pH
For each .1 change in pH how much of a change in calcium is there?
0.12
When should you correct for acidosis?
What happens to the unbound faction?
<7.36
increase
What is the equation for for acidosis corrections?
[7.36-pH] /.83 + CaT
What is the equation for alkalosis?
[ph-7.44]/.83 - CaT
What is the function of phosphate?
explain them.
it is a catalyst for numerous enzymatic ractions in the body.
essential in the phospholipid membrane of cells, nucleic acids, phosphoproteins, modifying calcium concentrations, reguations metabolism of proteins, fats, and carbs, regulates enzymatic reactions such as glycolysis, ammoniagenesis, regulates 2, 3 DPG, source of high energy ATP bonds
What is the normal serum phosphate?
2.6-4.5
How much phosphate is reabsorbed in the proximal tubule?
85-90%
How is elimination determined?
Filtration- reabsorption
Where is the parathyroid hormone released from?
the parathyroid glands
What does an increase in parathyroid hormone do??
increases calcium, decrease phosphorous
What does parathyroid hormone do to bone?
increases osteoclastic activity, decreases osteoblastic activity decreases osteoblastic activity resulting in mobilization of calcium > phosphate
What does parathyroid hormone do to the kidney
increases reabsorption of calcium and decreases phosphate reabsorption in the renal tubules
What does parathyroid hormone do to GI tract?
it increases the conversion of Vitamin D to 1,25 dihydroxycholecalciferol (calcitrol) promoting the absorption of calcium by the intestine
