endocrine and metabolic disorders
Hypernatremia
Key Points
Hypernatremia is usually caused by limited access to water or an impaired thirst mechanism, and less commonly byarginine vasopressindeficiency or resistance (formerly diabetes insipidus). Manifestations include confusion, neuromuscular excitability, hyperreflexia, seizures, and coma. Patients who do not respond to simple rehydration or in whom there is no obvious cause may need assessment of urine volume and osmolality, particularly after water deprivation. Replace intravascular volume and free water orally or intravenously at a rate dictated by how acutely (< 24 hour) or chronically (> 24 hour) the hypernatremia has developed, while watching other serum electrolyte levels (especially potassium and bicarbonate) as well. 