Hyponatremia Flashcards
What is hyponatremia defined as?
Sodium
What are the symptoms of hypnatremia?
Asx, or confusion, lethargy, muscle cramps, hyporeflexia, nausea… can progress to seizures, coma, brain stem herniation.
What is the first step in the workup of hyponatremia?
Determine serum osmolality.
How do you determine serum osmolality?
2 * Na + Glu/18 + BUN/2.8
Normal = 280-295.
What causes hyperosmolality w hyponatremia?
Hyperglycemia, hyperproteinemia, alcohol sugars, basically any other “stuff”.
What if the osmolality is normal?
Isotonic -? pseudohyponatremia.
If the serum osmolality is low, what is the next step in diagnosis?
Volume status.
If the patient with hypo-osmolar hyponatremia is volume up, what is the DDx?
renal failure, cirrhosis, nephrotic syndrome, CHF.
What is the treatment for hypervolemic hypoosmolar hyponatremia?
Water restriction.
If the patient with hypo-osmolar hyponatremia is volume down, what is the DDx?
Diuretics, diarrhea, dehydration, emesis, third spacing.
What is the treatment for hypovolemic hypo-osmolar hyponatremia?
replete water with normal saline.
What is the risk of correction hypovolemia too quickly?
Central pontine myelinosis also known as osmotic demyelination syndrome.
How quickly to correct hypovolemic hypo-osmolar hyponatremia?
Only by 4-6 pts in the first 24 hrs, then over 48-72 hrs.
Under what conditions should hyponatremia be treated with hypertonic saline?
Severe sxs, very very low sodium (like
What are the causes of euvolemic hypoosmolar hyponatremia?
Renal failure (RTAs) Addision's/adrenal insuff. Thyroid dz (hypo) SIADH (or psychogenic polydipsia - water deprivation test will determine). Drugs (?)
