Endocrine Abstracts

Introduction: Hyponatraemia is the most frequent electrolyte disturbance in clinical practice. It is encountered in isolation or as a complication of other medical conditions. The classification of hyponatraemia by volume status and severity – mild (125–134 mmol/l), moderate (115–124 mmol/l), and severe (<115) is of significance both prognostically and as a means of guiding management.

Methodology: A retrospective review was carried out into diagnosis and investigations of patients presenting to Acute Medical Unit at Solihull Hospital over a period of one month as either primary-care referrals for, or incidental findings of hyponatraemia. The focus of this audit was on the management of patients presenting with moderate–severe hyponatraemia, with local trust guidelines determining this as a serum sodium concentration of <125 mmol/l.

Aims: To determine whether patients presenting to AMU underwent necessary investigations and diagnostic work-up as stipulated by NICE guidelines. These investigations include: serum/urine osmolality, TFT’s, urinalysis, serum cortisol, myeloma screen, CXR, fluid intake, and medication review.

Results: Over this evaluation period, 33 patients were found to be moderately–severely hyponatraemic. The majority (85%) of these patients were identified incidentally. Those presenting with severe hyponatraemia accounted for 50% of primary care referrals for hyponatraemia in comparison to incidental findings of 11%. Fifty-five percent of patients presenting with hyponatraemia were on medications exacerbating this: offending medications were suspended in 89% of these patients during their admission. The full diagnostic work-up was not used in a single patient; with a myeloma screen being the least frequently requested investigation. However an underlying aetiology was found in 70% patients, with clinical improvement in 85%, highlighting the importance of clinical judgement in requesting appropriate investigations. Four out of 33 patients (12%) died during hospital admission suggesting a high mortality rate.