How should I manage a patient with mild hypernatraemia (sodium levels 145-150 mmol/L) without significant symptoms?

Management of a patient with mild hypernatremia (sodium 145-150 mmol/L) who is asymptomatic:

• Assess the patient's hydration status carefully to determine if there is any dehydration or fluid imbalance.
• If the patient is clinically euvolemic and without symptoms, monitor serum sodium levels regularly to detect any progression or worsening.
• Review and address any underlying causes such as inadequate water intake, excessive sodium intake, or conditions causing free water loss.
• Encourage oral fluid intake to correct mild hypernatremia gradually, avoiding rapid correction to prevent cerebral edema.
• If dehydration is present, calculate the water deficit and replace it cautiously over 48 hours, initially using isotonic fluids such as 0.9% sodium chloride, then consider hypotonic fluids if hypernatremia persists.
• Monitor plasma electrolytes every 4 to 6 hours during correction to ensure the rate of sodium decrease does not exceed 12 mmol/L per 24 hours.
• Refer to specialist care if hypernatremia worsens, symptoms develop, or if the cause is unclear.

This approach aims to safely manage mild hypernatremia in the community or outpatient setting while preventing complications from rapid sodium shifts.