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Three Part Question

In [exercise associated symptomatic hyponatraemia] does [fluid resuscitation with hypertonic saline] [decrease mortality]

Clinical Scenario

A 35 year old triathelete presents to the emergency department following a long distance event. He feels dizzy, nauseated, fatigued and has some degree of confusion. A clinical diagnosis of symptomatic hyponatraemia is made when his arterial blood gas sample shows a sodium level of 120 mmol/L.

Search Strategy

Medline 1966- 2011/12 using the OVID interface
(("exercise"[MeSH Terms] OR "exercise"[All Fields]) AND associated[All Fields] AND ("hyponatraemia"[All Fields] OR "hyponatremia"[MeSH Terms] OR "hyponatremia"[All Fields]) AND ("saline solution, hypertonic"[MeSH Terms] OR ("saline"[All Fields] AND "solution"[All Fields] AND "hypertonic"[All Fields]) OR "hypertonic saline solution"[All Fields] OR ("hypertonic"[All Fields] AND "saline"[All Fields]) OR "hypertonic saline"[All Fields])) AND (English[lang] AND ("1966"[PDAT] : "2011/12"[PDAT]))
Embase 1966- current year
(exercise AND associated AND hyponatraemia AND hypertonic AND saline).ti,ab [Limit to: Publication Year 1966-Current and English Language]

Search Outcome

Medline: 18 papers were found, of which 0 directly answered the question
Embase: 3 papers were found, all of which were identified in the Medline search.

Comment(s)

There is currently no available clinical evidence that identifies a measurable decrease in mortality with the use of hypertonic saline in exercise-associated hyponatraemia (EAH). A number of case reports/series have been published and the consensus is treatment of EAH with hypertonic saline. There is insufficient evidence to identify a decrease in mortality, a randomized control is recommended.

Clinical Bottom Line

Hypertonic saline is typically used in patients with severe EAH, but no published evidence was found to answer the 3-part question: Local/National advice should be followed.