The environment plays a large role in your success as a medic in survival settings. If you don’t take weather conditions and other factors into account, you have made the environment your enemy … and it’s a formidable one. Different areas might pose special challenges. If you live in Miami, you might be treating a lot of people with heat stroke. If you live in Siberia, you’ll be treating a lot of people with cold-related exposure. In many places, you might be treating both,
depending on the time of year.
Illness related to cold temperatures is known as “hypothermia.” Normally, the body core ranges from 97.5 to 99.5 degrees Fahrenheit (36.5 to 37.5 degrees Celsius). Hypothermia begins when the body core drops below 95 degrees.HEAT LOSS
The body loses heat in various ways.
❰ Evaporation—Perspiration from physical exertion, overheating or other reasons release heat from the body core.
❰ Radiation—The body loses heat to the environment when the surrounding temperature is below the body’s core
temperature. For example, you lose more heat if exposed to an outside temperature of 20 degrees (F) than if exposed to 80 degrees (F).
❰ Conduction—The body loses heat when its surface is in direct contact with cold temperatures, as in the case of someone falling from a boat into frigid water. Water, being denser than air, removes heat from the body much faster.
❰ Convection—Heat loss when, for instance, a cooler object is in motion against the body core. The air next to the skin is heated and then removed, which requires the body to use energy to reheat. Wind chill is one example of air convection:
If the ambient temperature is 32 degrees (F) but the wind chill factor is at 5 degrees, you lose heat from your body as if it were actually 5 degrees.
“If you don’t take weather conditions into account, you have made the environment your enemy… and it’s a formidable one.”
When it is exposed to cold, the body kicks into action to produce heat. It does this by the use of muscle actions as the core cools. Muscles shiver to produce heat and are a warning that you need to warm up. As hypothermia worsens, more symptoms will become apparent. Aside from shivering, the most noticeable symptoms of hypothermia will be related to mental status. The person might appear confused, uncoordinated and lethargic.
The victim’s speech becomes slurred, and they often appear uninterested in helping themselves. All this occurs as a result of the effect of cooling temperatures on the brain: The colder the body core gets, the slower the brain works. Other organs begin to shut down, and the victim loses consciousness. Any unconscious person you find exposed to cold weather should be considered hypothermic until proven otherwise.
Cold-related tissue effects also include local damage, such as frostbite. Frostbite affects areas such as the fingers, toes, nose, earlobes and even lips. Sometimes called “frostnip” or “chilblains” in early stages, it begins as numbness, a pins-and-needles sensation and redness. Blistering could occur.
If not warmed, the skin turns progressively white and waxy and then blue, and finally, black—a condition known as “gangrene.” Gangrenous tissue is dead and unsalvageable in survival settings and might require debridement (the removal of dead tissue) or amputation.HYPOTHERMIA PREVENTION
“An ounce of prevention is worth a pound of cure,” and many cases of hypothermia can be prevented. To prevent hypothermia, you must anticipate the climate you will be traveling through, including wind conditions and wet weather. Condition yourself physically to be fit for the challenge. If at all possible, travel with a partner, and have enough food and water available for the entire trip.
Remember the simple acronym, “COLD”: Cover, Overexertion, Layers and Dry.
Cover: Dress appropriately for the weather. Protect your head by wearing a hat. This will prevent body heat from escaping from your head. Instead of using gloves to cover your hands, use mittens. Mittens are more helpful than gloves, because they keep your fingers in contact with one another; this conserves heat.
Overexertion: Avoid activities that cause you to sweat a lot. Cold weather causes you to lose body heat quickly; wet, sweaty clothing accelerates the process. Rest when necessary, and use rest periods to self-assess for cold-related changes. Pay special attention to the status of any elderly or juvenile group members. Diabetics are also at high risk.DRESS IN LAYERS
Loose-fitting, lightweight clothing in layers creates a thin layer of warm air in between and does the best job of insulating you against the cold. Use tightly woven, water-repellent material for exterior layer wind protection. Wool or silk inner layers hold body heat better than cotton does. Some synthetic waterproof/breathable materials such as Gore-Tex also work well. Take special care to cover your head, neck, hands and feet.STAY DRY
Keep as dry as you can. Get out of wet clothing as soon as possible. It’s very easy for snow to get into gloves and boots, so pay particular attention to your hands and feet. Keep extra socks handy, and replace moist
socks as often as necessary.
Immediate measures must be taken to reverse the ill effects of hypothermia. Failure to act quickly could lead to organ failure and death. Important measures to take include:
Get the victim out of the cold. Transport them to a warm, dry location. If you’re unable to do this, shield them as much as possible. Be sure to place a barrier between them and the cold ground.
Monitor breathing. A person with severe hypothermia might be unconscious. Verify that the victim is breathing, and check for a pulse. Begin CPR if necessary.
Take off wet clothing. If the person is wearing wet clothing, gently remove it. Cover the victim with layers of dry blankets, including their head, but leave their face clear.
Share body heat. To warm the person’s body, remove your clothing and lie next to the person, making skin-to-skin contact. Cover both of your bodies with blankets. Some people might cringe at this notion, but it’s important to remember that you are trying to save a life. Lightly rubbing the affected areas might help restore circulation. However, vigorous movements could be traumatic.
Give warm fluids. If the affected person is alert and able to swallow, provide a warm, nonalcoholic, non-caffeinated beverage to help warm the body. Alcohol does not warm you up; rather, it expands blood vessels and actually hastens the loss of heat from the body core.
Use warm, dry compresses. Use a first aid warm compress or a makeshift compress of warm (not hot) water in a plastic bottle. Apply compresses to the neck, armpit and groin. These areas will transport heat to the body core more effectively than placing warm compresses on the extremities, which sometimes worsens the condition.
Avoid applying direct heat. Don’t use hot water, a heating pad or a heating lamp directly on the victim. The extreme heat can damage the skin, cause strain on the heart—or even lead to cardiac arrest.STRANDED!
The concern of anyone stranded in the cold, whether it’s in the wilderness, an urban environment or a vehicle, is to find the warmest shelter available. In the post-collapse city, many abandoned buildings will provide a refuge from the wind and possibly fuel to build a fire. A vehicle can also serve as a shelter, but do not start a fire inside it, no matter how small.
In the forest, a “tree well” shelter can be constructed out of the snow. A tree well is the sunken area around the trunk in very deep snow. This area is relatively easy to excavate and, if the tree has low-hanging branches, should provide some protection from falling snow. Look for natural barriers nearby that could serve as windbreaks, but beware of slopes, on which you might be exposed to drifting snow or avalanches.
“If the car motor runs, turn it on for only about 10 minutes each hour for heat.”
The space you dig out should be small, because small shelters take less effort to keep warm than large ones. Pack your snow “walls” well so they can retain heat better and support a makeshift roof. Place evergreen boughs and debris on the floor to protect you from the cold ground. Then, add some on top to make a roof. Tarps or solar blankets can be used for this purpose, but winds might blow them off. Tie rocks to the corners as anchors. If you make a fire, be sure to have ventilation holes in your shelter. Entrances and ventilation holes should open at a 90-degree angle to the prevailing winds.
Let’s say you’re stuck in a stalled car on the road in a blizzard. Stay in the vehicle: Thanks to your body heat, the temperature in the vehicle will be warmer than outside. In addition, you have protection from the wind. Leaving the vehicle might disorient you in driving snow. If the car motor runs, turn it on for only about 10 minutes each hour for heat.
Although the heater helps, wet snow can block up your exhaust system and cause carbon monoxide gas to enter the passenger compartment. You’ll need fresh air, so crack a window on the opposite side from where the wind is coming. If you’re in a group, huddle together as best as you can to create a warm pocket in the car. Your muscles produce heat involuntarily by shivering, but you can rub your hands, put them in your armpits or otherwise keep moving to achieve the same goal.THE WINTER SURVIVAL CAR KIT
There are a number of items you should always have in your car—especially in cold weather. These are meant to keep you safe if the unthinkable happens and you’re stranded without hope of rescue. A full set of camping supplies would be useful to keep if you have space in your car, but there are some items that are especially important to stow:
❰ Wool blankets (for warmth; wool can stay warm, even if wet)
❰ Spare sets of dry clothes, especially socks, hats and mittens
❰ Hand warmers or other instant heat packs (activated by shaking; they’ll last for hours)
❰ Matches, lighters and fire starters to generate heat
❰ Flashlights and candles (to extend the batteries’ life, insert them backward into the flashlight until you need them)
❰ Small multi-tool with blade, screwdrivers, pliers, etc.
❰ Larger combination tool such as a folding military entrenching tool (it functions as a shovel but also as an axe, hoe, saw, etc.)
❰ Sand or rock salt (to give traction where needed)
❰ Tow chain or rope
❰ Road flares
❰ Jumper cables (the longer, the better)
❰ Water and food (energy bars, MREs, dehydrated soups, candies)
❰ Baby wipes (for hygiene purposes)
❰ A medical kit and medications
❰ Tarp and duct tape (brightly colored ones will be more visible and will aid rescue)
❰ Metal cup or thermos (to melt snow, make soup, etc.)
❰ Emergency whistle to signal for help
❰ Cell phone and charger
❰ Weather radio
It should be noted that some of the above materials, such as jumper cables, are also quite helpful
in normal times, when rescue resources are available. Winter can be harsh, but with some planning and supplies, it can be just a bump in the road and not the end of the road. Act quickly to help a victim of hypothermia, and you’ll save a life.
Editor’s note: A version of this article first appeared in the January 2017 issue of American Survival Guide.