Renal: Hypo- or Hypernatremia Treatment

Question 1

Hypernatremia and hyponatremia are caused by issues with salt or issues with water?

Answer 1

Hyponatremia and hypernatremia are caused by too much or too little water

Question 2

If a patient is hyponatremia and hypovolemic, with a U[Na] >30 it is due to renal or extra renal issues?

Answer 2

Renal

-diuresis, mineralocorticoid deficiency , salt losing neprhopathy etc

Question 3

If a patient is hyponatremia and hypovolemic, with a U[Na] <30 it is due to renal or extra renal issues?

Answer 3

Extrarenal issues

-vomiting, diarrhea, third spacing (burns)

Question 4

If a patient is hyponatremia and euvolemic, with a U[Na] >30 it is due to what? (2 big ones)

Answer 4

Glucocorticoid deficiency

SIADH

Question 5

If a patient is hyponatremia and hypervolemic, with a U[Na] >30 it is due to what?

Answer 5

Acute or chronic renal failure

Question 6

If a patient is hyponatremia and hypervolemic, with a U[Na] <30 it is due to what? (3)

Answer 6

Nephrotic syndrome
Cirrhosis
Cardiac failure

Question 7

If a patient has mild hyponatremia (headache, irritability, lack of concentration, altered mood) how would you treat?

Answer 7

Fluid restriction

Question 8

If a patient has moderate hyponatremia (nausea, confusion, disorientated, altered mental status) how woul you treat?

Answer 8

Vaptan or hypertonic NaCl followed by fluid restriction

Question 9

If a patient has severe hyponatremia (vomiting, seizures, obtundation) how would you treat?

Answer 9

hypertonic NaCl followed by fluid restriction or vaptan

Question 10

Why should you not correct hyponatremia too quickly?

Answer 10

It can cause osmotic demyelination syndrome

Question 11

Conivaptan MOA

Answer 11

V1 and V2 vasopressin receptor antagonist

-promotes excretion of free water

Question 12

Which vaptan is administered orally and is selective for V2 only?

Answer 12

Tolvaptan

Question 13

When would you give conivaptan to a patient?

Answer 13

If the pt is euvolemic or hypervolemic with hyponatremia and is symptomatic

Question 14

How long should you give a patient tolvaptan?

Answer 14

<30 days

-can cause hepatotoxicity

Question 15

What is another use of tolvaptan, besides hyponatremia?

Answer 15

Slows progression of adult Polycystic Kidney Disease

-must monitor LFTs

Question 16

If a patient is hypovolemic and has hypernatremia, what should you give?

Answer 16

isotonic saline or hypotonic IV solutions like D5W

Question 17

MOA of desmopressin

Answer 17

ADH analogue at V2 receptor

Question 18

Clinical applications of desmopressin?

Answer 18

Central diabetes insipidus

Primary nocturnal enuresis (bedwetting)

Question 19

Adverse reactions of desmopressin?

Answer 19

Hyponatremia
-seizures, coma, respiratory arrest

Hypotension

Thrombosis and MI
-from increasing factor VII and vWF

Question 20

How do you treat central diabetes insipidus (from lack of ADH)?

Answer 20

Desmopressin

Question 21

What would you give in nephrogenic diabetes insipidus, not due to lithium?

Answer 21

Thiazides

Question 22

What would you give for lithium induced nephrogenic diabetes insipidus?

Answer 22

Amiloride

-blocks influx of Li into principal cells