Introduction: Hyponatraemia is defined as serum sodium concentration <135 mmol/l. It is the most common electrolyte disorder encountered in clinical practise. It is associated with an increase in mortality and length of stay, independent of diagnosis and clinical variables. Despite this it is often inadequately investigated and poorly managed.
Methods: A retrospective audit was performed of patients admitted to The Great Western Hospital (GWH) serum sodium of 127 mmol/l or less on admission, over a 3-month period. The aim was to identify whether a diagnosis of hyponatraemia is made and to evaluate how these patients are investigated.
Results: Seventy-five patients were included in the audit; 27 males (36%) and 48 females (64%). The mean age was 75 years (range 3794 years). All patients had a serum sodium of 127 mmol/l or less on admission: mean 122 mmol/l and range 108127 mmol/l. Only 65% of patients had hyponatraemia documented as either a diagnosis or problem. Only 28% of patients had their fluid status documented. Eight investigations were identified as essential when investigating patients with hyponatraemia. Only 4% of patients had all eight investigations completed during admission. Less than 27% of patients had a urine sodium, urine osmolality, and serum osmolality requested during admission.
Discussion: This audit clearly demonstrates that clinicians do not recognise hyponatraemia as a problem, and are therefore not making a diagnosis and requesting the appropriate investigations.