Aims Hyponatraemia is the most common body fluid disorders but often goes unnoticed. Our laboratory incorporated a standardised procedure to help clinicians detect moderate/severe hyponatraemia. The study aims were to evaluate the outcomes on patient care and clinicians’ satisfaction.

Methods The study, observational and retrospective, included 1839 cases, adult and paediatric patients, with sodium concentration <130 mmol/L. The procedure consisted of interpretative comments in the emergency and core laboratories report and the point-of-care testing blood gas network report. We evaluated hyponatraemia length in two equal periods: before and after the implementation. We conducted a survey addressed to the staff of the clinical settings involved to know their satisfaction.

Results The median hyponatraemia length decreased significantly from 4.95 hours (2.08–16.57) in the first period to 2.17 hours (1.06–5.39) in the second period. The lack of hyponatraemia patients follow-up was significantly less after the procedure implementation. The survey was answered by 92 (60 senior specialists and 32 residents) out of 110 clinicians surveyed. Ninety of them (98%) answered positively.

Conclusions We have demonstrated the reduction in the time for diagnosing and management by physicians, the higher uniformity in the time required to solve hyponatraemia episodes following our laboratory procedure and the clinicians’ satisfaction.