Renal System >
Hypernatremia
“Elevated levels of serum sodium concentration (>145mmol/L) causing hyperosmolar state“
Risk Factors
- Modifiable:
- Poorly controlled diabetes
- Fluid loss via vomiting or diarrhoea
- Increased sodium diet
- Non-Modifiable:
- Increasing age
Aetiology
- Diuretics eg loop diuretics
- Dehydration
- Diabetes insipidus
Pathophysiology
- Loop diuretics
- Inhibit Na reabsorption in nephrons
- Increased water clearance only while Na remains
- Diabetes insipidus
- Lack of ADH production
- Less water reabsorbed by kidney tubules
- Dilute urine production
- Greater Na concentration remaining
- Diarrhoea & vomiting
- Fluid loss without replacement
Clinical Presentation
- Polydipsia
- Decreased skin turgor
- Dry skin
- Lethargy
- Confusion
- Advanced cases:
- Muscle twitching
- Spasms
Investigations
- Bloods:
- Serum electrolytes: sodium, potassium, chloride
- Urea & Electrolytes
- Creatinine
- Blood Gas
- Imaging: n/a
- Special: n/a
Management
- Correcting fluid and sodium balance.
- Mild cases: increase fluid intake
- Severe cases: IV drip (dextrose 5%)
Complications
- Correcting sodium concentration too quickly = cerebral oedema risk