Data from: Electrolyte imbalances in an unselected population in an emergency department: a retrospective cohort study

Background: Although electrolyte imbalances (EIs) are common in the
emergency department (ED), few studies have examined the occurrence of
such conditions in an unselected population. Objectives: To investigate
the frequency of EI among adult patients who present to the ED, with
regards to type and severity, and the association with age and sex of the
patient, hospital length of stay (LOS), readmission, and mortality.
Methods: A retrospective cohort study. All patients ≥18 years referred for
any reason to the ED between January 1, 2010, and December 31, 2015, who
had measured blood electrolytes were included. In total, 62 991 visits
involving 31 966 patients were registered. Results: EIs were mostly mild,
and the most common EI was hyponatremia (glucose-corrected) (24.6%).
Patients with increasing severity of EI had longer LOS compared with
patients with normal electrolyte measurements. Among all admitted
patients, there were 12928 (20.5%) readmissions within 30 days from
discharge during the study period. Hyponatremia (glucose-corrected) was
associated with readmission, with an adjusted odds ratio (OR) of 1.25 (95%
CI, 1.18–1.32). Hypomagnesemia and hypocalcemia (albumin-corrected) were
also associated with readmission, with ORs of 1.25 (95% CI, 1.07–1.45) and
1.22 (95% CI, 1.02–1.46), respectively. Dysnatremia, dyskalemia,
hypercalcemia, hypermagnesemia, and hyperphosphatemia were associated with
increased in-hospital mortality, whereas all EIs except hypophosphatemia
were associated with increased 30-day and 1-year mortality. Conclusions:
EIs were common and increasing severity of EIs was associated with longer
LOS and increased in-hospital, 30-days and 1-year mortality. EI monitoring
is crucial for newly admitted patients, and up-to-date training in EI
diagnosis and treatment is essential for ED physicians.