K, Ca, P, Mg

Question 1

98% of potassium is

Answer 1

Intracellular

Question 2

What are normal serum levels of potassium

Answer 2

3.5-5.0 mEq/l

Question 3

Where is the majority of K located in the body

Answer 3

Muscles&raquo_space; bone, RBC, liver

Question 4

Low K in cells can relate to what acid/base imbalance

Answer 4

Acidosis

Question 5

What is normal plasma Ca

Answer 5

5.0 mEq/L

Question 6

Where is most Ca stored

Answer 6

Bone

Question 7

What does hypocalcemia do with neuromuscular excitability

Answer 7

Increases it

Leads to hypocalcemic tetany/spasticity

Question 8

What does hypercalcemia do to neuromuscular excitability

Answer 8

Depresses activity

Threshold shifts away from resting membrane potential

Question 9

What are the main regulators of Ca

Answer 9

PTH, calcitonin, calcitriol

Question 10

Elevated serum calcium can be

Answer 10

Primary hyperparathyroidism and malignancy

Question 11

Low serum calcium can be

Answer 11

Hypoparathyroidism, renal disease, or vitamin D deficiency

Question 12

Most Pi is found

Answer 12

In bones

Question 13

What is Pi levels related to

Answer 13

Levels of renal excretion

Question 14

What are the 4 main regulators of Pi

Answer 14

Dietary, calcitriol, PTH, renal tubular

Question 15

What does calcitriol do to Pi levels

Answer 15

Increased Pi resorption from bone and increased absorption from intestine

Question 16

How does PTH affect Pi levels

Answer 16

Phosphorus resorption directly from bone and indirectly activates intestinal absorption through stimulation of calcitriol production

Question 17

How does renal tubules affect Pi

Answer 17

Reabsorption of Pi, which is stimulated by tubular filtered load of Pi and inhibited by PTH

Question 18

Where is most magnesium stored

Answer 18

50% in bone and 49% in ICF in muscle

Question 19

What is Mg depletion associated with

Answer 19

Migraine, depression, epilepsy, SIDS, arrhythmia, preeclampsia, muscle cramps

Question 20

What effect does PTH cause

Answer 20

Increase serum Ca and decrease serum Pi

Question 21

Excess PTH can cause

Answer 21

Hypercalcemia, hypophosphatemia, hypercholermic metabolic acidosis

Question 22

What stimulates calcitonin release

Answer 22

Hypercalcemia

Question 23

What does calcitriol do

Answer 23

Increase serum Ca and Pi

Question 24

Deficiency in calcitriol is thought to contribute to

Answer 24

Chronic pain

Question 25

What does calcitonin do

Answer 25

Decreases serum Ca and Pi