Electrolytes

Question 1

Rapid increase in sodium causes what complication?

Answer 1

osmotic demyelination

Question 2

Rapid decrease in sodium causes what complication?

Answer 2

cerebral edema

Question 3

Mechanism of action of tolvaptan?

Answer 3

vasopressin receptor. blocker

Question 4

Tolvaptan pushes sodium which direction?

Answer 4

Up

Question 5

3 medical conditions to void desmopresin in?

Answer 5

HF, psychosis, cirrhosis

Question 6

Other than emergencies, what rate should you raise Na by?

Answer 6

4-6 in the first few hours, then 9/day.

Question 7

Desmopressin pushes sodium which direction?

Answer 7

down

Question 8

Medical condition to avoid giving tolvaptan in?

Answer 8

Cirrhosis

Question 9

In hypovoleumic, hyponatremia, what lab value helps determine renal vs extra-renal water loss?

Answer 9

• UrNa >20 means renal loss.

- UrNa < 10 means extra-renal loss.

Question 10

Rate of correction of hypernatremia?

Answer 10

<10/day if chronic (correct in 24 hours if acute)

Question 11

EKG changes in hypokalemia?

Answer 11

ST depression, small T waves, U waves.

Question 12

Arrhythmias common with kypokalemia?

Answer 12

Sinus bracycardia, AV block VT, VF, Torsades

Question 13

EKG changes in hyperkalemia?

Answer 13

Peaked T waves. Long PR. Wide QRS. Loss of P waves. Sine wave.

Question 14

Symptoms of hypocalcemia?

Answer 14

Tetany, seizures, hypotension, QTc prolongation. Anxiety, psychosis.

Question 15

Correction for hypocalcemia due to hypoalbuminemia?

Answer 15

For each 1g/dL decrease in albumin, correct the calcium by 0.8.

Question 16

Calcium level required for symptoms from hypercalcemia?

Answer 16

> 14

Question 17

EKG findings of hypercalcemia?

Answer 17

Short QTc, tall/broad T wave.Osbourne/J-waves look like dicrotic notches.

Question 18

Tx hypercalcemia?

Answer 18

• IVF for UOP 100-150/hr.
• Calcitonin.
• Bone resorption blocker (zolendronic acid, pamidronate)

Question 19

Sx hypomagnesemia?

Answer 19

Tetany, weakness, coma. Arrhythmias (AF, Torsades).

Question 20

SIADH criteria?

Answer 20

Serum Osm < 275. Euvoleumia. UrNa > 40.