Overview
Hypernatremia, characterized by elevated serum sodium levels (≥150 mmol/L), can result from various etiologies including dehydration, inadequate fluid intake, and conditions affecting osmoregulation. It poses significant risks, particularly in vulnerable populations such as pediatric and geriatric patients, often linked with organ dysfunction and adverse outcomes like mortality and intracranial complications 12.Diagnosis
Key Diagnostic Criteria: Elevated serum sodium levels (≥150 mmol/L) 12.
Recommended Tests: Assess plasma and urine osmolality, urine sodium concentration, and evaluate for underlying causes like chronic diseases, medication effects, and fluid management practices 12.
Grading: Severity can be graded based on the degree of hypernatremia and presence of neurological symptoms 1.Management
First-Line Treatments: Gradual correction of hypernatremia to avoid cerebral edema; typically involves fluid replacement with hypotonic solutions 12.
Adjunctive Treatments: Continuous arteriovenous haemodiafiltration for severe cases with renal failure when peritoneal dialysis is contraindicated 3.
Specific Considerations: Monitor closely for complications such as rhabdomyolysis, myoglobinuria, respiratory failure, and cardiac arrhythmias in severe cases 5.Special Populations
Pediatrics: Commonly associated with chronic diseases, hospital-acquired conditions, and medication-related factors; high mortality risk if organ dysfunction is present 1.
Geriatrics: Higher mortality rates observed, especially in ICU settings; ICU admission significantly increases mortality risk 2.
Comorbidities: Presence of underlying chronic diseases and organ dysfunction significantly impacts prognosis 12.Key Recommendations
Gradually correct hypernatremia to minimize neurological risks (Evidence: Moderate 12).
Thoroughly evaluate and manage underlying causes, including medication effects and fluid management practices (Evidence: Moderate 12).
Utilize advanced dialysis modalities like continuous arteriovenous haemodiafiltration for refractory cases with renal failure (Evidence: Weak 3).
Intensive care monitoring is crucial for geriatric patients, particularly those in ICU settings due to significantly higher mortality risk (Evidence: Moderate 2).
Closely monitor for and manage complications such as rhabdomyolysis and renal insufficiency in severe hypernatremia cases (Evidence: Weak 5).References
1 Mihara A, Nishi K, Hayakawa I, Kato H, Tsuboi N, Ogura M et al.. Impact of organ dysfunction on outcomes in pediatric hypernatremia: a retrospective observational study. Pediatric nephrology (Berlin, Germany) 2025. link
2 Toor MR, Singla A, DeVita MV, Rosenstock JL, Michelis MF. Characteristics, therapies, and factors influencing outcomes of hospitalized hypernatremic geriatric patients. International urology and nephrology 2014. link
3 Moss GD, Primavesi RJ, McGraw ME, Chambers TL. Correction of hypernatraemia with continuous arteriovenous haemodiafiltration. Archives of disease in childhood 1990. link
4 Felig P, Johnson C, Levitt M, Cunningham J, Keefe F, Boglioli B. Hypernatremia induced by maximal exercise. JAMA 1982. link
5 Opas LM, Adler R, Robinson R, Lieberman E. Rhabdomyolysis with severe hypernatremia. The Journal of pediatrics 1977. link81233-x)