According to the Mayo Clinic, “Hypothermia is a medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature.” A normal, healthy body temperature should average around 98.6 degrees Fahrenheit. Hypothermia occurs when your body temperature drops below 95 degrees Fahrenheit.
While most people associate hypothermia with extreme cold environments, hypothermia can occur as a result of rain, wind, or water. Age, medical conditions, dehydration, alcohol use, and strenuous activity can all play a role in hypothermia, so it’s good to be prepared as it can strike during any season.
When setting out on a backcountry trip it’s better to be over prepared than under prepared. Even if it’s warm and sunny when you start your hike, weather/conditions can change quickly in the mountains and you may soon be facing cool temperatures or find yourself caught in a rainstorm.
Dress appropriately. Heading out in shorts and a t-shirt is fine but be sure and bring layers. Do your research ahead of time and prepare for the worst. Be sure and bring waterproof outer layers and warm base layers. Avoid cotton as it easily soaks up water and takes a long time to dry – wool, silk, and polypropylene are better options.
Most importantly, be sure and stay dry to avoid losing body heat. If you do get wet, change clothes immediately.
Recognize the Signs
Hypothermia can often be difficult to recognize in the early stages but it is important to catch it as soon as possible (as it can be life threatening if not treated quickly and properly).
According to WebMD, the main symptoms associated with hypothermia are shivering (may stop as hypothermia progresses), slow and shallow breathing, confusion, memory loss, drowsiness, exhaustion, slurred speech, loss of coordination, a slow/weak pulse, and in severe cases, a loss of consciousness.
In infants, hypothermia usually manifests itself with unusually low energy and bright red skin that is cold to the touch.
How Heat Is Lost
The body loses heat in four different ways: evaporation, radiation, conduction, and convection. When you sweat, water evaporates from your skin, which can cause you to lose heat – during intense exercise 85 percent of body heat is lost through sweat.
Wet clothes or heavy breathing can also cause the body to lose heat via evaporation. Radiation is the process of heat moving away from the body and typically occurs when temperatures drop below 68 degrees Fahrenheit – 65 percent of body heat is lost via radiation.
Conduction occurs when heat is lost from sleeping on a cold floor or from submersion in cold water – roughly 2 percent of body heat is lost as a result of air conduction. Lastly, convection occurs in heavy winds, causing the body to lose 10-15 percent of its heat.
Treatment: Mild and Severe Cases
In cases of mild hypothermia, your first priority should be to move the person out of the cold and into a sheltered environment. Next, you’ll want to remove all wet clothing and replace with warm, dry clothes.
To slow the rate of heat loss, wrap the affected person in a sleeping bag or tarp – it can also be helpful to put a second person in the sleeping bag for added heat. Give the victim warm food and sugary drinks, but steer clear of alcohol or caffeinated beverages. Avoid using hot water bottles or heat packs as this can impair the body's shivering mechanism. Try building a fire or having the patient inhale steam from boiled water.
In cases of severe hypothermia, handle the victim very gently as their heart is at risk. Place the patient in a sleeping bag and stack blankets and clothing on top of them to prevent further cooling.
If the victim has an altered mental state, avoid giving them food or water (this can be a choking hazard). Seek help immediately and initiate an evacuation to get the affected to a hospital for professional help.
In cases where there is no sign of breathing or a pulse after one minute, CPR may be necessary (if there is any sign of a pulse or breathing avoid administering CPR).
Seek emergency help immediately and move the victim to a warm, protected environment. CPR can be delayed for up to 10 minutes if safety is a concern. Once you begin, CPR should be administered continuously. Regular chest compressions should be administered and ventilation should be given at a normal rate (unless the patient has advanced airway).
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