title: Treatment of hyponatremic encephalopathy with a 3% sodium chloride protocol: a case series.
abstract: BACKGROUND
  3% sodium chloride solution is the accepted treatment for hyponatremic encephalopathy, but evidence-based guidelines for its use are lacking.
  
  
  METHODS
  A case series.
  
  
  METHODS
  Adult patients presenting to the emergency department of a university hospital with hyponatremic encephalopathy, defined as serum sodium level < 130 mEq/L with neurologic symptoms of increased intracranial pressure without other apparent cause, and treated with a continuous infusion of 500mL of 3% sodium chloride solution over 6 hours through a peripheral vein.
  
  
  METHODS
  Hyponatremic encephalopathy defined as serum sodium level < 130 mEq/L with neurologic symptoms of increased intracranial pressure without other apparent cause.
  
  
  RESULTS
  Change in serum sodium level within 48 hours, improvement in neurologic symptoms, and clinical evidence of cerebral demyelination, permanent neurologic injury, or death within 6 months' posttreatment follow-up.
  
  
  RESULTS
  There were 71 episodes of hyponatremic encephalopathy in 64 individuals. Comorbid conditions were present in 86% of individuals. Baseline mean serum sodium level was 114.1±0.8 (SEM) mEq/L and increased to 117.9±1.3, 121.2±1.2, 123.9±1.0, and 128.3±0.8 mEq/L at 3, 12, 24, and 48 hours following the initiation of 3% sodium chloride solution treatment, respectively. There was a marked improvement in central nervous system symptoms within hours of therapy in 69 of 71 (97%) episodes. There were 12 deaths, all of which occurred following the resolution of hyponatremic encephalopathy and were related to comorbid conditions, with 75% of deaths related to sepsis. No patient developed neurologic symptoms consistent with cerebral demyelination at any point during the 6-month follow-up period.
  
  
  CONCLUSIONS
  Lack of a comparison group and follow-up neuroimaging studies. Number of cases is too small to provide definitive assessment of the safety of this protocol.
  
  
  CONCLUSIONS
  3% sodium chloride solution was effective in reversing the symptoms of hyponatremic encephalopathy in the emergency department without producing neurologic injury related to cerebral demyelination on long-term follow-up in this case series.
authors.affiliation: Renal Consultants of Houston, Houston, TX; Nephrology Division, Hospital Italiano, Buenos Aires, Argentina. Electronic address: carlosayus@yahoo.com.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Ayus
authors.affiliation: Nephrology Division, Hospital Alejandro Posadas, Buenos Aires, Argentina.
authors.forename: Daniel
authors.initials: D
authors.lastname: Caputo
authors.affiliation: Centro de Rehabilitacion Hirsch, Buenos Aires, Argentina.
authors.forename: Fernando
authors.initials: F
authors.lastname: Bazerque
authors.affiliation: Nephrology Division, Hospital Fernandez, Buenos Aires, Argentina.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Heguilen
authors.affiliation: Pharmacology Division, Universidad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Claudio D
authors.initials: CD
authors.lastname: Gonzalez
authors.affiliation: Division of Nephrology, Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Moritz
mesh_terms: D000368:Aged; D001929:Brain Edema / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012462:Saline Solution, Hypertonic / Q000008:administration & dosage* / Q000737:chemistry; D016896:Treatment Outcome
chemical_list: D012462:Saline Solution, Hypertonic
keywords: 3% sodium chloride; Hyponatremia; cerebral demyelination; electrolyte abnormality; hypertonic saline; hyponatremic encephalopathy; neurologic injury; sodium