Hiker Fatality From Severe Hyponatremia in Grand Canyon National Park.
We present the case of a hiker who died of severe hyponatremia at Grand Canyon National Park. The woman collapsed on the rim shortly after finishing a 5-hour hike into the Canyon during which she was reported to have consumed large quantities of water. First responders transported her to the nearest hospital. En route, she became unresponsive, and subsequent treatment included intravenous normal saline. Imaging and laboratory data at the hospital confirmed hypervolemic hyponatremia with encephalopathy. She never regained consciousness and died of severe cerebral edema less than 24 hours later. We believe this is the first report of a fatality due to acute hyponatremia associated with hiking in a wilderness setting. This case demonstrates the typical pathophysiology, which includes overconsumption of fluids, and demonstrates the challenges of diagnosis and the importance of appropriate acute management. Current treatment guidelines indicate that symptomatic exercise-associated hyponatremia should be acutely managed with hypertonic saline and can be done so without concern over central pontine myelinolysis, whereas treatment with high volumes of isotonic fluids may delay recovery and has even resulted in deaths.
Branch of Emergency Services, Grand Canyon National Park, Grand Canyon, AZ (Dr Myers). Electronic address: canyondoc@gmail.com.
Thomas M
TM
Myers
Department of Physical Medicine and Rehabilitation, Department of Veterans Affairs, Northern California Health Care System, and the University of California Davis Medical Center, Sacramento, CA (Dr Hoffman).
Martin D
MD
Hoffman
D001130:Arizona; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D008875:Middle Aged; D000068316:Parks, Recreational; D010807:Physical Endurance; D005082:Physical Exertion; D012462:Saline Solution, Hypertonic / Q000627:therapeutic use
D012462:Saline Solution, Hypertonic
arginine vasopressin; cerebral edema; exercise-associated hyponatremia; hypertonic saline; syndrome of inappropriate ADH secretion; water-electrolyte imbalance