RC5.1 - ECE_1698 - Adherence to ESE and SfE guidance in the management of severe hyponatraemia: a multicentre audit of real-world practice

Abstract Background Severe hyponatraemia is a high-risk endocrine emergency. The European Society of Endocrinology (ESE) and the Society for Endocrinology (SfE) guidelines recommend symptom-based use of hypertonic saline (HTS), monitored care, and prevention of overly rapid sodium correction. However, real-world adherence is uncertain. Objectives To evaluate adherence to ESE and SfE guidelines in severe hyponatraemia management and identify key patient safety gaps and real-world practice patterns. Methods We conducted a retrospective, multicentre audit of adult inpatient admissions between 1 January and 31 December 2024 with a serum sodium concentration ≤125 mmol/L. Adherence to key standards from ESE and SfE guidelines was assessed, including documentation of symptom severity, appropriate use of HTS for moderate or severe symptoms, monitoring following HTS administration, correction rates within recommended limits, location of care during HTS administration, completeness of diagnostic evaluation, and involvement of specialist endocrinology services. Results A total of 1121 admissions were analysed. Median age was 72.0 years (IQR 62.0-82.0), and 52.0% (n = 583) were female. Symptom-based assessment was documented in 87.8% (n = 984) of admissions; 13.9% (n = 137) had severe and 19.9% (n = 196) moderate symptoms. Based on ESE/SfE criteria, 29.7% (n = 333) of patients met indications for HTS, yet only 26 (7.8%) received HTS. In contrast, 7 patients with mild symptoms received HTS despite not meeting guideline criteria. Among 33 HTS prescriptions, 54.5% (n = 18) were administered in monitored environments (emergency department or intensive care), and 54.5% (n = 18) followed bolus-based regimens. Serum sodium was rechecked within one hour of the first bolus in 66.7% (n = 22) of cases. Sodium correction data at 24 hours were available in 58.9% (n = 661) of admissions, and overcorrection (>10 mmol/L/24 h) occurred in 4.7% (n = 53). Diagnostic evaluation was incomplete, with urine sodium and osmolality measured in 50.0% and 50.9% of admissions, respectively. Specialist endocrinology input was documented in 27.0% of cases. Osmotic demyelination syndrome was confirmed in one case (0.1%) and suspected in three (0.3%). Conclusions Management of severe hyponatraemia was suboptimal, characterised by underutilisation of HTS in eligible patients, inconsistent monitoring, and incomplete diagnostic evaluation. These findings highlight significant patient safety gaps and underscore the need for system-level interventions, including education, standardised pathways, and improved access to specialist endocrine input.