| Hypernatremia | |
|---|---|
| Other names | Hypernatraemia |
 | |
| Sodium | |
| Specialty | Hospital medicine |
| Symptoms | Feeling of thirst, weakness, nausea, loss of appetite[1] |
| Complications | Cardiac arrest, confusion, muscle twitching, bleeding in or around the brain[1][2] |
| Types | Low volume, normal volume, high volume[1] |
| Diagnostic method | Serum sodium > 145 mmol/L[3] |
| Differential diagnosis | Low blood protein levels[4] |
| Frequency | ~0.5% in hospital[2] |
Hypernatremia, also spelled hypernatraemia, is a high concentration of sodium in the blood.[3] Early symptoms may include a strong feeling of thirst, weakness, nausea, and loss of appetite.[1] Severe symptoms include confusion, muscle twitching, and bleeding in or around the brain.[1][2] Normal serum sodium levels are 135–145 mmol/L (135–145 mEq/L).[5] Hypernatremia is generally defined as a serum sodium level of more than 145 mmol/L.[3] Severe symptoms typically only occur when levels are above 160 mmol/L.[1]
Hypernatremia is typically classified by a person's fluid status into low volume, normal volume, and high volume.[1] Low volume hypernatremia can occur from sweating, vomiting, diarrhea, diuretic medication, or kidney disease.[1] Normal volume hypernatremia can be due to fever, extreme thirst, prolonged increased breath rate, diabetes insipidus, and from lithium among other causes.[1] High volume hypernatremia can be due to hyperaldosteronism, excessive administration of intravenous normal saline or sodium bicarbonate, or rarely from eating too much salt.[1][2] Low blood protein levels can result in a falsely high sodium measurement.[4] The cause can usually be determined by the history of events.[1] Testing the urine can help if the cause is unclear.[1] The underlying mechanism typically involves too little free water in the body.[6]
If the onset of hypernatremia was over a few hours, then it can be corrected relatively quickly using intravenous normal saline and 5% dextrose in water.[1] Otherwise, correction should occur slowly with, for those unable to drink water, half-normal saline.[1] Hypernatremia due to diabetes insipidus as a result of a brain disorder, may be treated with the medication desmopressin.[1] If the diabetes insipidus is due to kidney problems the medication causing the problem may need to be stopped or the underlying electrolyte disturbance corrected.[1][7] Hypernatremia affects 0.3–1% of people in hospital.[2] It most often occurs in babies, those with impaired mental status, and the elderly.[2] Hypernatremia is associated with an increased risk of death, but it is unclear if it is the cause.[2]
- ^ a b c d e f g h i j k l m n o p Reynolds, RM; Padfield, PL; Seckl, JR (25 March 2006). "Disorders of sodium balance". BMJ (Clinical Research Ed.). 332 (7543): 702–5. doi:10.1136/bmj.332.7543.702. PMC 1410848. PMID 16565125.
- ^ a b c d e f g Lin, M; Liu, SJ; Lim, IT (August 2005). "Disorders of water imbalance". Emergency Medicine Clinics of North America. 23 (3): 749–70, ix. doi:10.1016/j.emc.2005.03.001. PMID 15982544.
- ^ a b c Muhsin, SA; Mount, DB (March 2016). "Diagnosis and treatment of hypernatremia". Best Practice & Research Clinical Endocrinology & Metabolism. 30 (2): 189–203. doi:10.1016/j.beem.2016.02.014. PMID 27156758.
- ^ a b Kliegman, Robert M.; Stanton, Bonita M. D.; Geme, Joseph St; Schor, Nina F. (2015). Nelson Textbook of Pediatrics (20 ed.). Elsevier Health Sciences. p. 348. ISBN 9780323263528. Archived from the original on 2017-09-08.
- ^ Kuruvilla, Jaya (2007). Essentials of Critical Care Nursing. Jaypee Brothers Publishers. p. 329. ISBN 9788180619205.[permanent dead link]
- ^ Ranasinghe, Sudharma; Wahl, Kerri M.; Harris, Eric; Lubarsky, David J. (2012). Anesthesiology Board Review Pearls of Wisdom 3/E. McGraw Hill Professional. p. 6. ISBN 9780071773638.
- ^ Khanna, A (May 2006). "Acquired Nephrogenic Diabetes Insipidus". Seminars in Nephrology (Review). 26 (3): 244–8. doi:10.1016/j.semnephrol.2006.03.004. PMID 16713497.