Global InformationHyponatremia information
| Hyponatremia | |
|---|---|
| Other names | Hyponatraemia, low blood sodium, hyponatræmia |
 | |
| Sodium, as shown on the periodic table | |
| Specialty | Nephrology |
| Symptoms | Decreased ability to think, headaches, nausea, poor balance, confusion, seizures, coma[1][2][3] |
| Types | Low volume, normal volume, high volume[4] |
| Diagnostic method | Serum sodium < 135 mmol/L[3] |
| Differential diagnosis | Ethanol intoxication or withdrawal, high protein levels, high blood fat levels, high blood sugar[5][6] |
| Treatment | Based on underlying cause[4] |
| Frequency | Relatively common[6][7] |
Hyponatremia or hyponatraemia is a low concentration of sodium in the blood.[4] It is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe hyponatremia being below 120 mEq/L.[3][8] Symptoms can be absent, mild or severe.[2][9] Mild symptoms include a decreased ability to think, headaches, nausea, and poor balance.[1][3] Severe symptoms include confusion, seizures, and coma;[1][2][9] death can ensue.[10]
The causes of hyponatremia are typically classified by a person's body fluid status into low volume, normal volume, or high volume.[4] Low volume hyponatremia can occur from diarrhea, vomiting, diuretics, and sweating.[4] Normal volume hyponatremia is divided into cases with dilute urine and concentrated urine.[4] Cases in which the urine is dilute include adrenal insufficiency, hypothyroidism, and drinking too much water or too much beer.[4] Cases in which the urine is concentrated include syndrome of inappropriate antidiuretic hormone secretion (SIADH).[4] High volume hyponatremia can occur from heart failure, liver failure, and kidney failure.[4] Conditions that can lead to falsely low sodium measurements include high blood protein levels such as in multiple myeloma, high blood fat levels, and high blood sugar.[5][6]
Treatment is based on the underlying cause.[4] Correcting hyponatremia too quickly can lead to complications.[5] Rapid partial correction with 3% normal saline is only recommended in those with significant symptoms and occasionally those in whom the condition was of rapid onset.[4][6] Low volume hyponatremia is typically treated with intravenous normal saline.[4] SIADH is typically treated by correcting the underlying cause and with fluid restriction while high volume hyponatremia is typically treated with both fluid restriction and a diet low in salt.[1][4] Correction should generally be gradual in those in whom the low levels have been present for more than two days.[4]
Hyponatremia is the most common type of electrolyte imbalance, and is often found in older adults.[11][12] It occurs in about 20% of those admitted to hospital and 10% of people during or after an endurance sporting event.[3][5] Among those in hospital, hyponatremia is associated with an increased risk of death.[5] The economic costs of hyponatremia are estimated at $2.6 billion per annum in the United States.[13]
- ^ a b c d Cite error: The named reference
babarwas invoked but never defined (see the help page). - ^ a b c Williams, DM; Gallagher, M; Handley, J; Stephens, JW (July 2016). "The clinical management of hyponatraemia". Postgraduate Medical Journal. 92 (1089): 407–11. doi:10.1136/postgradmedj-2015-133740. PMID 27044859.
- ^ a b c d e Henry, DA (4 August 2015). "In The Clinic: Hyponatremia". Annals of Internal Medicine. 163 (3): ITC1–19. doi:10.7326/aitc201508040. PMID 26237763. S2CID 12434550.
- ^ a b c d e f g h i j k l m n Lee, JJ; Kilonzo, K; Nistico, A; Yeates, K (13 May 2014). "Management of hyponatremia". CMAJ: Canadian Medical Association Journal. 186 (8): E281–86. doi:10.1503/cmaj.120887. PMC 4016091. PMID 24344146.
- ^ a b c d e Filippatos, TD; Liamis, G; Christopoulou, F; Elisaf, MS (April 2016). "Ten common pitfalls in the evaluation of patients with hyponatremia". European Journal of Internal Medicine. 29: 22–25. doi:10.1016/j.ejim.2015.11.022. PMID 26706473.
- ^ a b c d Marx, John; Walls, Ron; Hockberger, Robert (2013). Rosen's Emergency Medicine – Concepts and Clinical Practice (8 ed.). Elsevier Health Sciences. pp. 1639–42. ISBN 978-1-4557-4987-4. Archived from the original on 2016-08-15.
- ^ Ball, SG; Iqbal, Z (March 2016). "Diagnosis and treatment of hyponatraemia". Best Practice & Research. Clinical Endocrinology & Metabolism. 30 (2): 161–73. doi:10.1016/j.beem.2015.12.001. PMID 27156756.
- ^ Chatterjee, Kanu; Anderson, Mark; Heistad, Donald; Kerber, Richard E. (2014). Manual of Heart Failure. JP Medical Ltd. p. 142. ISBN 978-93-5090-630-9 – via Google Books.
- ^ a b Ball, S; De Groot, LJ; Beck-Peccoz, P; Chrousos, G; Dungan, K; Grossman, A; Hershman, JM; Koch, C; McLachlan, R; New, M; Rebar, R; Singer, F; Vinik, A; Weickert, MO (2000). "Hyponatremia". Endotext. PMID 25905359. Accessed 1 August 2016.
- ^ Pilling, Kim (8 November 2022). "Doctor Found Guilty of Trying to Conceal Cause of Child's Death". Medscape UK.
- ^ Valle, Jana M.; Beveridge, Alexander; Chróinín, Danielle Ní (2022-02-16). "Exploring hyponatremia in older hospital in-patients: management, association with falls, and other adverse outcomes". Aging and Health Research. 2: 100060. doi:10.1016/j.ahr.2022.100060. ISSN 2667-0321. S2CID 246938773.
- ^ Dineen, R; Thompson, CJ; Sherlock, M (June 2017). "Hyponatraemia – presentations and management". Clinical Medicine. 17 (3): 263–69. doi:10.7861/clinmedicine.17-3-263. PMC 6297575. PMID 28572229.
- ^ Simon, Eric E. (2014). Hyponatremia: Evaluation and Treatment. Springer Science & Business Media. p. 205. ISBN 978-1-4614-6645-1. Archived from the original on 2016-08-15.