Hypernatremia

Question 1

In hypernatrema, what is the cause (conceptual)?

Answer 1

Too little water, rather than too much salt.

Question 2

What is the cutoff for hypernatremia?

Answer 2

> 145

Question 3

What are the symptoms of hypernatremia?

Answer 3

thirst, altered mental status, weakness, focal neurologic deficits, seizures.

Question 4

What may you find on physical exam of hypernatremia?

Answer 4

doughy skin, signs of volume depletion.

Question 5

What are the three categories of causes for hypernatremia?

Answer 5

Hypertonic Na+ gain
Pure water loss
Hypotonic fluid loss

Question 6

What are the causes of hypertonic Na+ gain?

Answer 6

hypertonic saline, hyperaldosteronism.

Question 7

What are the causes of pure water loss?

Answer 7

Central or nephrogenic diabetes insipidous causes large volumes of dilute urine. Dermal/respiratory insensible losses.

Question 8

What are the causes of hypotonic fluid loss?

Answer 8

Decreased intake, diuretics, renal disease, GI losses (diarrhea), burns, osmotic diuresis (mannitol).

Question 9

How to treat hypernatremia?

Answer 9

Replace water deficit with oral water, normal saline, or if severe, D5W. Correction should occur over 48-72 hours.

Question 10

What is the consequence of too-rapid correction of hypernatremia?

Answer 10

Cerebral edema.