title: Inadvertent hyponatremia leading to acute cerebral edema and early evidence of herniation.
abstract: BACKGROUND
  For years, the maintenance of normal or supranormal serum sodium (Na) concentrations has been believed to be beneficial in brain injuries. Recently published guidelines for cerebral trauma recommend the use of hypertonic saline to achieve hypernatremia for the management of increased intracranial pressure and these standards are generally practiced across most diseases in neurocritical care including stroke, hemorrhage and tumors. Severe hyponatremia has long been known to be detrimental, but objective evidence for the harm of mild hyponatremia as a secondary injury has been scarce.
  
  
  METHODS
  In this case report, we describe a child with aneurysmal subarachnoid hemorrhage who had a sudden, inadvertent decrease in serum Na (128 meq/l) that was associated with a deterioration of her neurological examination and evidence of early transtentorial herniation on emergent brain CT scan. These findings were quickly reversed after the serum Na was corrected.
  
  
  CONCLUSIONS
  This report emphasizes that close monitoring of serum Na and osmolarity in acute head injured children is important, and provides evidence that alterations of these parameters is a substantial risk for cerebral edema in children with evolving brain injuries and briefly reviews the literature regarding the risks of hyponatremia in children.
authors.affiliation: Department of Neurology, Children's Research Institute, Children's National Medical Center, Washington, DC, USA. jcarpent@cnmc.org
authors.forename: Jessica
authors.initials: J
authors.lastname: Carpenter
authors.forename: Steve
authors.initials: S
authors.lastname: Weinstein
authors.forename: John
authors.initials: J
authors.lastname: Myseros
authors.forename: Gilbert
authors.initials: G
authors.lastname: Vezina
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Bell
mesh_terms: D000208:Acute Disease; D001929:Brain Edema / Q000000981:diagnostic imaging / Q000209:etiology*; D002526:Cerebellar Diseases / Q000000981:diagnostic imaging / Q000209:etiology*; D002648:Child; D004677:Encephalocele / Q000000981:diagnostic imaging / Q000209:etiology*; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000150:complications* / Q000188:drug therapy / Q000209:etiology; D002532:Intracranial Aneurysm / Q000150:complications; D012462:Saline Solution, Hypertonic / Q000627:therapeutic use; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000209:etiology; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D012462:Saline Solution, Hypertonic