Hypernatremia was found in 5-Minute Clinical Consult which helps you diagnose, treat, and follow up on over 900 medical conditions seen in everyday practice.
Explore 5-Minute Clinical Consult - view these FREE monographs:
-- The first section of this topic is shown below --
- Serum sodium (Na) concentration >145 mEq/L
- Often represents a state of hyperosmolality.
- Sodium concentration reflects balance between total body water and total body sodium. Hypernatremia occurs from deficit of water relative to sodium.
- Hypernatremia results from net water loss or, more rarely, from primary Na gain.
- May exist with hypo-, hyper-, or euvolemia, although hypovolemia is by far most common type:
- Hypovolemic: Occurs with a decrease in total body water (TBW) and a proportionately smaller decrease in total body Na.
- Euvolemic: No change in TBW with a proportionate increase in total body Na
- Hypervolemic: Increase in TBW and a proportionately greater increase in total body Na
- Old age
- Patients who are intubated/have altered mental status
- Diabetes mellitus
- Prior brain injury
- Diuretic therapy, especially loop diuretics
- Lithium treatment
Some forms of diabetes insipidus may be hereditary.
- Treatment/Prevention of underlying cause
- Properly prepare infant formula and never add salt to any commercial infant formula.
- Keep patients well hydrated.
- Pure water loss (total body Na normal) resulting from:
- Adipsia/Hypodipsia (e.g., impaired thirst regulation, decreased access to water)
- Nephrogenic diabetes insipidus (due to progressive renal dysfunction, hypercalcemia, hypokalemia, medication-related particularly lithium, or congenital)
- Central diabetes insipidus (due to head trauma, stroke, meningitis)
- Increased insensible water loss (e.g., fever, hyperventilation, hypermetabolic state, heat exposure, newborns under radiant warmers)
- Hypotonic fluid loss (total body Na decreased) resulting from:
- Loss of fluid containing relatively more water than Na (e.g., excessive sweating, severe burns)
- Urinary loss:
- Osmotic diuresis: Hyperglycemia, mannitol
- Diuretics, especially loop diuretics
- Diabetes mellitus, particularly new presentation/decompensated
- Post-ATN or postobstructive diuresis
- Intrinsic renal disease
- Gastrointestinal loss:
- Diarrhea, especially in children
- Vomiting, nasogastric (NG) lavage
- Enterocutaneous fistula
- Excess Na (increase in total body Na) resulting from (2):
- IV NaCl or NaHCO3 during cardiopulmonary resuscitation, metabolic acidosis, or hyperkalemia
- Sea water ingestion
- Excessive use of NaHCO3 antacid
- Incorrect infant formula preparation
- Intrauterine NaCl for abortion
- Excessive Na in dialysate solutions
- Disorders of the adrenal axis (Cushing syndrome, Conn syndrome, congenital adrenal hyperplasia)
- Tube feeds
Commonly Associated Conditions
- Altered mental status
- Hypermetabolic conditions
- Head injury
- Renal dysfunction