Dysnatraemias in the emergency room: Undetected, untreated, unknown?

Hypo- and hypernatraemia are the most common electrolyte disorders in hospitalized patients and have been associated with increased mortality. However, data on the prevalence of dysnatraemias in the emergency room and the characteristics of patients presenting with them are rare.

In this retrospective study, we analyzed data from patients who presented to the emergency department of a large tertiary university hospital between September 1st 2010 and November 30th 2010 and who received measurement of serum sodium.

3,182 patients received measurement of serum sodium during the three-month study period. 124 patients (4%) presented with hyponatraemia on admission to the emergency department while 400 patients (13%) presented with hypernatraemia. While there was no difference in age between patients with hypernatraemia and those who were normonatraemic, patients with hyponatraemia were significantly older.

Dysnatraemias are present in almost 1 in 5 patients who presented to the emergency department. Contrarily to patients who are already hospitalized, hypernatraemia was by far more common than hyponatraemia in patients at the emergency department. Surprisingly, patients with hyponatraemia were significantly older than normonatraemic patients while there was no age difference in hypernatraemic patients. Dysnatraemias are common in the emergency room and further studies are indicated to evaluate the causes and the impact on outcome of patients.