Cold Weather and Hypothermia Ever done one or more of these activities in the
winter- canoeing, kayaking, down hill and cross country skiing, climbing,
hiking, back packing, or hunting. All of these situations generally place you
remote in locations, and remote locations generally mean minimal medical
assistance. Hypothermia occurs when more heat is lost than the body can
generate. This causes the core temperature (temperature around the brain and
major organs) to fall. In order to stay warm we need to understand how we loose
Body heat is lost in four main ways:
- Radiation- this occurs when the ambient temperature is less than 98.6° F.
- Conduction- heat transfer from the body to an adjoining surface. This can be rocks, ground water, etc. Water takes away heat 25 times faster than air, so you can see the importance of staying dry.
- Convection- air currents against the body- wind chill
- Evaporation- sweating Hypothermia is defined as a core body temperature of less than 95° F.
Signs and symptoms include:
- Slurred speech
- Abnormally slow breathing
- Cold, pale skin
- Loss of coordination
- Fatigue, lethargy or apathy
In his Outdoor Activity Guide to Hypothermia, Rick Curtis says “watch for the
"-Umbles" - stumbles, mumbles, fumbles, and grumbles which show changes in
motor coordination and levels of consciousness.”
The onset of hypothermia is insidious- what begins as a mild case may
progress to severe hypothermia without much warning. Mild hypothermia may
exhibit normal shivering, goose bumps or loss of finger dexterity. As
hypothermia progresses to a moderate stage, shivering intensifies and may
become violent; muscle control degrades and coordination deteriorates; mild
confusion may occur. As the condition worsens, shivering stops; although the
person may be able to stand, walking is very difficult; confusion deepens or
irrational behavior may become evident. In severe hypothermia muscles become
rigid; heart and respiration rates decrease; awareness of others decreases;
and unconsciousness can occur. The best treatment for hypothermia is
- Wear appropriate clothing in layers to stay warm and prevent sweating. Head covering is essential
- Drink plenty of fluids- NO ALCOHOL or CAFFEINE
- Don’t go into the cold alone
When I was in the Navy we lost one of the sailors from the ship. He had gone
on a wine tasting in the mountains of Andorra, a country between Spain and
France. It seems he got hot in the tasting room and wandered outside alone to
“cool off.” He violated all of the prevention guides mentioned above. By the
time his shipmates missed him and located him, it was too late to save him.
Treatment of hypothermia is not always simple. For mild hypothermia you want to
stop heat loss by adding additional layers of warm, dry coverings. Get into a
shelter, if possible. Also try to get warm liquids into the person. For more
severe cases, a thermal blanket might be necessary. Warm food or liquids that
can help the body generate heat are needed. Concentrate on warming the core
Treating severe hypothermia is complicated. Doing CPR could be live saving or
it could lead to fibrillation and cause death. “Afterdrop” is caused during the
warming process. Cold blood from the limbs can actually reduce the core
temperature during warming. That is why we concentrate on warming the core.
These kinds of techniques are best performed by a professional.
Winter camping can be fun. Be prepared for that cold and respect the danger.
For a more complete discussion on hypothermia, visit the sites below. A “Wind Chill
Factor” table is located in the Images and Forms section of the website.