Best approach for treating HYPOnatremia

Consider a single bolus of 100 to 150 mL of 3% saline over 10 to 20 minutes for MODERATE symptoms (nausea, headache, or confusion) IF sodium.....
Mahitab Hany, BS Pharm, PGDipClinPharm, PGDipClinNutrition

What is the best approach for teating hyponatremia? ㅡ Usually focus on the symptoms more than the sodium level. We know to immediately treat SEVERE symptoms such as seizure and coma with hypertonic saline to prevent brain herniation and death. But other cases of hyponatremia aren't as clear cut.

  • Consider a single bolus of 100 to 150 mL of 3% saline over 10 to 20 minutes for MODERATE symptoms (nausea, headache, or confusion) IF sodium is below 130 mEq/L. Patients with these symptoms can rapidly deteriorate.
  • Rule out other causes, such as a stroke, when moderate or severe symptoms occur in the setting of mild hyponatremia (130 to 135 mEq/L).
  • If a patient with hyponatremia seems asymptomatic, evaluate for more subtle symptoms (gait changes, falls, difficulty concentrating, etc). Don't routinely use 3% saline in these patients, risk of overcorrection usually outweighs benefit.
  • Review medication lists of all patients with hyponatremia. If appropriate, stop offenders such as carbamazepine or oxcarbazepine, SSRIs or SNRIs and thiazides. Also look for abruptly stopped corticosteroids which may cause hyponatremia due to acute adrenal insufficiency.
  • Expect to see fluid restriction for patients with syndrome of inappropriate antidiuretic hormone (SIADH). Stop "free water" flushes per tube and when able, change D5W to saline in continuous IV medications and piggybacks.
  • If these strategies aren't effective, consider adding treatment to raise the sodium. But be aware, there's no evidence that these treatments improve quality of life or decrease mortality. To increase free water in the urine, lean toward oral urea over oral tolvaptan (Samsca) or IV conivaptan (Vaprisol). Urea has similar sodium rises and seems safe. Plus "vaptans" have multiple drug interactions and expensive if compared with urea.

References

  1. Spasovski G, Vanholder R, Allolio B, Annane D, Ball S, Bichet D, Decaux G, Fenske W, Hoorn EJ, Ichai C, Joannidis M, Soupart A, Zietse R, Haller M, van der Veer S, Van Biesen W, Nagler E; Hyponatraemia Guideline Development Group. Clinical practice guideline on diagnosis and treatment of hyponatraemia. Eur J Endocrinol. 2014 Feb 25;170(3):G1-47.
  2. Verbalis JG, Goldsmith SR, Greenberg A, Korzelius C, Schrier RW, Sterns RH, Thompson CJ. Diagnosis, evaluation, and treatment of hyponatremia: expert panel recommendations. Am J Med. 2013 Oct;126(10 Suppl 1):S1-42.
  3. Decaux G, Andres C, Gankam Kengne F, Soupart A. Treatment of euvolemic hyponatremia in the intensive care unit by urea. Crit Care. 2010;14(5):R184.
  4. Soupart A, Coffernils M, Couturier B, Gankam-Kengne F, Decaux G. Efficacy and tolerance of urea compared with vaptans for long-term treatment of patients with SIADH. Clin J Am Soc Nephrol. 2012 May;7(5):742-7.