21st May 2025

You are asked to review a 60-year-old gentleman with a sodium of 128 mmol/L as he has become acutely confused over the past 3 hours.

You are asked to review a 60-year-old gentleman with a sodium of 128 mmol/L as he has become acutely confused over the past 3 hours. On review of his bloods, you note that he has had a sodium of between 129 – 131 mmol/L over the past 3 days. He remains asymptomatic of this and observations remain stable. Recent bloods demonstrate a serum osmolality is 230 mOsmol/kg. He is euvolaemic on examination. You feel that the likely cause of this is SIADH.

Which of the following management plans would be most appropriate? Please select only ONE answer.