Hypernatraemia
Hypernatraemia is usually a deficit of water relative to sodium; assess volume status and urine concentration, restore circulation first if shocked, then replace water in a controlled specialist-led plan.
Definition
Hypernatraemia is serum sodium above 145 mmol/L, usually reflecting a deficit of water relative to sodium and therefore increased plasma osmolality.
First principles
This is usually a water-access or water-loss problem
A serum sodium above 145 mmol/L represents excess sodium relative to body water. Common drivers are impaired thirst or access to water, gastrointestinal or insensible losses, osmotic diuresis and diabetes insipidus; true sodium gain is less common. Frail, dependent, confused, sedated and very young patients are particularly vulnerable.
This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.