983 Clinical audit of slow sodium in children and young people with syncope and/or orthostatic intolerance

Field: Medicine (Health Sciences)

Background

Approximately 15% of children will experience at least one episode of syncope in their adolescence, with it being more prevalent in females. Syncope is a symptom caused by transient global cerebral hypoperfusion, resulting in loss of consciousness. Frequent syncope and presyncope symptoms experienced preceding an episode can be disruptive to a child's lifestyle, causing embarrassment, anxiety and at times injury. Slow sodium is a therapy commonly used in adults with frequent syncope or orthostatic intolerance, taken together with advice to increase water intake, causing increased blood volume. Slow sodium has also been used in children at our local syncope clinic, however, there has been no recent review of its use.

Objectives

The aim of this audit of outcome was to determine whether slow sodium supplementation changed the rate of symptoms experienced in children less than 18 years old.

Methods

A retrospective analysis was conducted on consecutive patients at a single tertiary centre between 01–10-2014 to 30–09-2019. Patients dispensed slow sodium who were <18 years old, experienced syncope and/or pre-syncope symptoms or orthostatic intolerance, and were reviewed in the clinic during this time frame were included. Patients were excluded if they were treated by a joint slow sodium and fludrocortisone regime from the start of their treatment, used slow sodium for another indication, or had no follow-up appointment 1 year or more after starting treatment. Data was collected predominantly from clinic letters. Data was recorded both pre and 1 year post treatment, including demographic data, indication for slow sodium use (symptoms and diagnosis), frequency of symptoms, and adverse effects. Two scales were used to categorise the frequency of symptoms. The ordinal scale included categorising frequency of symptoms per day, week, month or year. The Clinical Global Impression (CGI) scale rated the change in symptoms as 'significantly worse', 'no clinically significant change' and 'significant improvement'.

Results

Overall, 81 patients were included, 54 female and 27 male, with a median age of 14 years (IQR 3). 77 patients had presyncopal and/or orthostatic symptoms, and 43 experienced transient loss of consciousness (TLOC) episodes. Most were dispensed a maintenance dose of 100mmol daily. The median dose of slow sodium was 1.62 mmol/kg daily (IQR 0.4 mmol/kg daily). The ordinal scale demonstrated improvement in frequency of orthostatic/presyncopal symptoms in 44/46 (95.7%), and improvement in frequency of TLOC in 21/21 (100.0%) evaluable patients, at 1 year or more follow-up. The CGI scale demonstrated improvement in frequency of orthostatic/presyncopal symptoms in 63/77 (81.8%), and improvement in frequency of TLOC in 40/43 (93.0%) by 1 year or more follow-up. 4/81 (4.9%) experienced nausea.

Conclusions

Slow sodium treatment appeared to be beneficial in reducing frequency of symptoms in the vast majority of patients, with only about 5% reporting adverse effects. However, a randomised double-blind placebo controlled clinical trial is required to prove efficacy by controlling for lifestyle advice, increased fluids, and the passage of time.