Hyponatraemia: clinical presentation, diagnosis and treatment

After reading this article, you should be able to:

• Describe hyponatraemia and appreciate the need for its judicious management;
• Understand the role of the extracellular cation sodium and be familiar with the reference range;
• List the investigations needed to confirm the cause of hyponatraemia, including serum osmolality, glucose, cortisol, thyroid function tests, urine osmolality and urine sodium;
• Apply knowledge from clinical cases to establish whether a clinical presentation of hyponatraemia is acute or chronic and describe relevant treatment plans;
• Identify the common causes of hyponatraemia.