Q: 38 year old marathon runner stopped running and he appears confused, dazed and found to be unaware of his environment. Paramedics at the site seek your advise, as you offer your services being a doctor and a good Samaritan. Paramedics wants to infuse 100 cc of 3 percent normal saline (3% NS)

A) Agree with their decision
B) Disagree with their decision
C) Agree with their decision, only if sodium measurement is available
D) Advise them not to do anything till patient get evaluated in emergency room (ER)
E) Advise to give patient a bottle of gatorade to drink


Answer: A

Though it sounds odd to give 3% NS in field without any sodium level check but according to 2015 Third International Exercise-Associated Hyponatremia Consensus Development Conference, any athlete who clinically exhibits symptoms of  hyponatremic encephalopathy should be immediately treated with a 100 mL bolus of 3% NS, irrespective of sodium level availability. This makes sense as benefit of preventing permanent neural damage secondary to hyponatremia is higher than mild bump in sodium level. In fact, as per guidelines, if symptoms persist, 3% NS bolus can be repeated  two more times at ten minutes interval (with the hope that by this time sodium level would be available)! 3% NS should not be given if serum sodium has risen 3 to 7 meq/L above the initial value, or neurological symptom resolves.



References:

1. Hew-Butler T, Rosner MH, Fowkes-Godek S, et al. Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015. Clin J Sport Med 2015; 25:303. 

2.  Siegel AJ, Verbalis JG, Clement S, et al. Hyponatremia in marathon runners due to inappropriate arginine vasopressin secretion. Am J Med 2007; 120:461.e11. 

3.  Hew-Butler T, Anley C, Schwartz P, Noakes T. The treatment of symptomatic hyponatremia with hypertonic saline in an Ironman triathlete. Clin J Sport Med 2007; 17:68. 

4. Ayus JC, Arieff A, Moritz ML. Hyponatremia in marathon runners. N Engl J Med 2005; 353:427.