Prevalence of falls in hyponatraemic patients presenting to an emergency department

Hyponatraemia is the most common electrolyte disturbance and is caused by either salt and water loss or water retention. The condition has been associated with gait disturbances and falls. We undertook a clinical audit of emergency presentations by patients with hyponatraemia. All emergency presentations to a tertiary level hospital who had an initial plasma electrolyte evaluation with a Na 129mmol/L were selected. Plasma osmolality, K, Cl, emergency and discharge diagnosis for each patient were collated. During January-August 2009, 375 specimens (from 300 patients) with Na ≤ 129mmol/L were received from the emergency department (ED). Only 59 specimens had an osmolality requested (16%). Forty-one of 300 patients presented to ED with a history of recurrent falls (13.7%) of whom 18 (43.9%) sustained a fracture as a result of the fall. The mean plasma Na in the fracture patients was 126 (120–129mmol/L) similar to the mean for all patients with falls (125.7, range 119–129mmol/L; mean age 81, range 55–96 years) but less than age matched controls (p