Yesterday heralded the running of a very wet, cool and cloudy American River 50 Mile run. The weather channel predicted it. Prior to driving north to Auburn from Yosemite, I packed the car with my essentials for a day of Medical Aid at the finish line.
The problem for the day was HYPOTHERMIA. Hypothermia essentially means, “too cold to rock and roll”, or a core drop in temperature of 3.6o F. Accidental hypothermia occurs in healthy individuals with simple environmental exposure. Three degrees is not much of a drop, but it is enough to get you in trouble on the trail. And it just gets worse as your temperature falls farther and farther.
It was towards the end of the run when we started to get our REALLY cold runners. That is to be expected. These are the folks out there the longest, and are not in the elite physical condition as the top runners. One participant was from Texas where the weather is hot. She was not acclimatized to the sudden change in weather.
Humans have a basal heat production of 50m2 BSA/hour. It is increased with eating, fever, activity (running) and shivering. It is lowered when the runner is in a cool climate, fuel depleted, fatigued, and dehydrated. Cold and exhaustion is the common denominator for accidental hypothermia and it DOES NOT take an extremely cold temperature to produce hypothermia after energy depletion.
Aid station personal or other runners can recognize trouble on the trail. I worry about it during nightfall and the wee hours of the morning at Western States.
Besides being cold and shivering, the runner may exhibit amnesia, inability to find the right words, poor judgment, anxiety, or become apathetic to the circumstances.
As the pendulum swings farther towards lower body temperatures, the person becomes stuporous and body functions decline.
Accurate measurement of core temperature is impractical for field treatment of hypothermia. Correction is essential! A field impression can be made by the circumstances of the discovery, duration of the exposure, predisposing conditions, and don’t forget any associated injuries.
If the person cannot swallow, and their mental facilities are severely compromised, activate the emergency medical services. Otherwise, strip the individual of ALL wet clothing and shoes. Dry and insulate. Wool, synthetics, space blankets or plastic bags will keep the heat in. Layer. There is NO ROLE for cotton. Cover the head. Hot packs (chemical pads or hot water in Nalgene bottles) should be placed in the armpits, groin, and on the neck. Heat the Core. Feed the runner hot cocoa, tea, hot Jell-o, or hot Tang. If you can, turn on the heater in the car, and allow the ambient heat of the vehicle to assist. If sitting on the ground, provide a pad or some type of insulation.
Prepare for bad weather. Use drop bags. Have dry clothes placed accordingly. I just touched on the topic of hypothermia. Physiologically it gets very complicated, but recognized early on, and corrected appropriately will save the runner from spiraling downward.
Right, left, right, left. Linda Lee