Phys: Electrolyte Disturbance: Ca, Mg, Phosphate Flashcards Preview

Week 2 > Phys: Electrolyte Disturbance: Ca, Mg, Phosphate > Flashcards

Flashcards in Phys: Electrolyte Disturbance: Ca, Mg, Phosphate Deck (22):
1

Calcium normal range

8.5-10

2

50% of calcium is bound to ______

Albumin

3

Majority of calcium is stored in the __________

Bones

4

Roles of Calcium

Coagulation, cell signaling, muscle contraction, neuromuscular transmission

5

Endocrine regulation of Calcium done by these 2 things

Calcitriol and PTH

6

Hypocalcemia

Causes: eating disorders, chelation therapy, low PTH, low vitamin D, tumor lysis

Clinical presentation: NM irritability, parasthesis (oral, perioral, a real) tingling or pin and needles, tenany, hyperreflexia, laryngospasm

ECG: prolonged QT interval

7

Hypercalcemia

Causes: Excess PTH, excess Vit D, Malignancy

Clinical presentation: constipation, fatigue, lethargy, depression, bone pain, kidney stones, anorexia, nausea, vomiting, pancreatitis

Psychiatric: Depression and confusion

EKG: Short QT interval, widened T wave

8

Renal regulation of Calcium

Kidneys excrete Ca in urine and kidneys are involved in forming Vit D

99% of filtered Ca is reabsorbed

Reabsorption of Ca is tightly coupled to Na

9

What is the major controller of GI calcium absorption?

Vitamin D

10

Ca++ reabsorption is tightly coupled to _______

Na+ reabsorption in the PCT and TALH

Only in the distal tubule is the reabsorption of the two ions dissociated

11

Magnesium normal range

1.5-2.0

12

Mg is a necessary __________ for many enzymed

Cofactor

13

Hypomagnesemia

Caused by: alcoholism, malnutrition, Chron's disease, Whipple's disease, celiac sprue

Renal Loss: Bartter's syndrome, Gitelman syndrome, Loop and thiazide diuretics side effect

Clinical presentation: weakness and muscle cramps, CNS-irritability, hallucinations, depression

EKG: Prolonged PR, QRS, and QT. Tornadoes de pointes, complete heart block and cardiac arrest, Cardiac arrythmias

14

Hypermagnesemia

Causes: cell lysis, hemolysis, tumor cell lysis, renal insufficiency

Clinical presentation: weakness, nausea, vomiting (4.0 mEq/L hyporeflexia)

EKG: arrhythmia and asystole
>5 : prolonged AV conduction
>10: complete heart block
>13 Cardiac arrest

Prolonged PR interval, shortened QT

15

Renal Regulation of Mg

Free component is freely filtered and then handled by the nephron almost identically to Calcium

16

Phosphate normal range

2.3-4.8

17

Phosphate

Necessary cofactor for many enzymes and is a major intracellular anion

18

Endocrine regulation of phosphate

Calcitriol and PTH

19

Hyperphosphatemia

Causes: hypoparathyroidism, chronic renal failure, tumor lysis

Clinical presentation: ectopic calcification

20

Hypophosphatemia

Causes: alcohol abuse, malabsorption

Clinical presentation: muscle dysfunction, respiratory depression, Rhabdomyolysis

21

90-95% f the total plasma phosphate is filterable at the ___________

Renal corpuscle

22

Filtered phosphate is actively reabsorbed in the ________

PCT (75-80%)