Hypernatremia in children
- Michael J Somers, MD
Michael J Somers, MD
- Associate Professor of Pediatrics
- Harvard Medical School
- Avram Z Traum, MD
Avram Z Traum, MD
- Instructor of Pediatrics
- Harvard Medical School
Hypernatremia is typically defined as a serum or plasma sodium greater than 150 mEq/L. Although pediatric hypernatremia is an uncommon electrolyte abnormality, there can be significant neurologic injury in patients with severe hypernatremia, especially those with acute and rapid changes in serum sodium.
The etiology, clinical findings, diagnosis, and evaluation of pediatric hypernatremia are reviewed here.
The true incidence of pediatric hypernatremia is unknown, as published data are based on hospitalized children.
As an example, a Scottish study reported an overall incidence of hypernatremia (defined as a plasma sodium >150 mEq/L) of 0.04 percent for all pediatric hospitalizations in pediatric patients over two weeks of age over a study period from 1996 to 2006 . However, the risk of hypernatremia was 10 times greater in neonates less than two weeks of age, with an incidence of 0.4 percent. Neonatal hypernatremia was almost exclusively seen in breastfed infants with excessive weight (water loss). Of note, the incidence of neonatal hypernatremia in breastfed infants was higher than reported in previous studies (0.03 to 0.07 percent) (see "Initiation of breastfeeding", section on 'Excessive weight loss'). In older patients between two weeks and 17 years of age, the most common cause of hypernatremia on admission was excess water loss due to gastroenteritis or systemic infection. However, in this cohort, it was more common for hypernatremia to develop during hospitalization, particularly in patients with systemic infection or those who underwent cardiac surgery. In addition, approximately one-third of the patients had an underlying neurologic condition.
In an earlier study from a tertiary children's hospital in Texas from 1992 to 1994, hypernatremia (defined as a serum sodium greater than 150 mEq/L) was detected in 1.4 percent of sodium values in a laboratory database, but only 0.2 percent of patients were discharged with a diagnosis of hyperosmolality due to hypernatremia . Of the 68 children with a final discharge diagnosis of hyperosmolality/hypernatremia, two-thirds of the children developed hypernatremia during hospitalization, and the most common cause of hypernatremia was inadequate fluid intake.To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:
- Forman S, Crofton P, Huang H, et al. The epidemiology of hypernatraemia in hospitalised children in Lothian: a 10-year study showing differences between dehydration, osmoregulatory dysfunction and salt poisoning. Arch Dis Child 2012; 97:502.
- Moritz ML, Ayus JC. The changing pattern of hypernatremia in hospitalized children. Pediatrics 1999; 104:435.
- Kaiser P, Borte M, Zimmer KP, Huppertz HI. Complications in hospitalized children with acute gastroenteritis caused by rotavirus: a retrospective analysis. Eur J Pediatr 2012; 171:337.
- Namdar T, Stollwerck PL, Stang FH, et al. Transdermal fluid loss in severely burned patients. Ger Med Sci 2010; 8:Doc28.
- Cooper WO, Atherton HD, Kahana M, Kotagal UR. Increased incidence of severe breastfeeding malnutrition and hypernatremia in a metropolitan area. Pediatrics 1995; 96:957.
- Moritz ML, Manole MD, Bogen DL, Ayus JC. Breastfeeding-associated hypernatremia: are we missing the diagnosis? Pediatrics 2005; 116:e343.
- Oddie S, Richmond S, Coulthard M. Hypernatraemic dehydration and breast feeding: a population study. Arch Dis Child 2001; 85:318.
- Oddie SJ, Craven V, Deakin K, et al. Severe neonatal hypernatraemia: a population based study. Arch Dis Child Fetal Neonatal Ed 2013; 98:F384.
- Iyer NP, Srinivasan R, Evans K, et al. Impact of an early weighing policy on neonatal hypernatraemic dehydration and breast feeding. Arch Dis Child 2008; 93:297.
- Schaff-Blass E, Robertson GL, Rosenfield RL. Chronic hypernatremia from a congenital defect in osmoregulation of thirst and vasopressin. J Pediatr 1983; 102:703.
- König R, Beeg T, Tariverdian G, et al. Holoprosencephaly, bilateral cleft lip and palate and ectrodactyly: another case and follow up. Clin Dysmorphol 2003; 12:221.
- Hoorn EJ, Betjes MG, Weigel J, Zietse R. Hypernatraemia in critically ill patients: too little water and too much salt. Nephrol Dial Transplant 2008; 23:1562.
- Paut O, André N, Fabre P, et al. The management of extreme hypernatraemia secondary to salt poisoning in an infant. Paediatr Anaesth 1999; 9:171.
- FINBERG L, KILEY J, LUTTRELL CN. Mass accidental salt poisoning in infancy. A study of a hospital disaster. JAMA 1963; 184:187.
- Meadow R. Non-accidental salt poisoning. Arch Dis Child 1993; 68:448.
- Wallace D, Lichtarowicz-Krynska E, Bockenhauer D. Non-accidental salt poisoning. Arch Dis Child 2017; 102:119.
- Dobato JL, Barriga FJ, Pareja JA, Vela L. [Extrapontine myelinolyses caused by iatrogenic hypernatremia following rupture of a hydatid cyst of the liver with an amnesic syndrome as sequela]. Rev Neurol 2000; 31:1033.
- Coulthard MG, Haycock GB. Distinguishing between salt poisoning and hypernatraemic dehydration in children. BMJ 2003; 326:157.
- Finberg L. Hypernatremic (hypertonic) dehydration in infants. N Engl J Med 1973; 289:196.
- FINBERG L. Pathogenesis of lesions in the nervous system in hypernatremic states. I. Clinical ovservations of infants. Pediatrics 1959; 23:40.
- Levene I. Towards evidence based medicine for paediatricians. Question 1: Is measurement of sodium from capillary blood accurate enough for clinical decision making? Arch Dis Child 2014; 99:481.
- Morimatsu H, Rocktäschel J, Bellomo R, et al. Comparison of point-of-care versus central laboratory measurement of electrolyte concentrations on calculations of the anion gap and the strong ion difference. Anesthesiology 2003; 98:1077.
- King RI, Mackay RJ, Florkowski CM, Lynn AM. Electrolytes in sick neonates - which sodium is the right answer? Arch Dis Child Fetal Neonatal Ed 2013; 98:F74.
- Fang C, Mao J, Dai Y, et al. Fluid management of hypernatraemic dehydration to prevent cerebral oedema: a retrospective case control study of 97 children in China. J Paediatr Child Health 2010; 46:301.
- El-Bayoumi MA, Abdelkader AM, El-Assmy MM, et al. Normal saline is a safe initial rehydration fluid in children with diarrhea-related hypernatremia. Eur J Pediatr 2012; 171:383.
- Kahn A, Brachet E, Blum D. Controlled fall in natremia and risk of seizures in hypertonic dehydration. Intensive Care Med 1979; 5:27.
- Excess water losses
- - Gastrointestinal loss
- - Urinary water loss
- Urinary concentration defects
- Osmotic diuresis
- - Skin loss
- - Inadequate water intake
- Infants and young children
- Impaired thirst mechanism
- Excess salt intake
- - Iatrogenic causes
- - Salt poisoning
- CLINICAL MANIFESTATIONS
- Acute hypernatremia
- Chronic hypernatremia
- Clinical evaluation
- Laboratory evaluation
- General principles
- Volume status and emergent fluid resuscitation
- Calculating the free water deficit
- - Prescribed fluid
- Rate of correction
- Ongoing losses and maintenance needs
- Treatment of specific etiologies
- Clinical example
- SUMMARY AND RECOMMENDATIONS