Throughout this article you will find affiliate links. These links will take you to the product or service mentioned. If you choose to make a purchase Adventure Feet First will receive a small commission, at no additional cost to you. We are so grateful for any affiliate purchases as they help us keep our content free to everyone!
Winter adventures present the opportunity to see the Earth after a costume change. Whether the land is snow covered or simply cold but bare, plants and animals wear their winter clothes, and even familiar places offer new discoveries. But cold-weather adventuring also presents the opportunity to develop hypothermia and frostbite, two potentially serious medical conditions. It’s important to note that while these conditions are risks in cold weather, “cold” can mean a summer rainstorm, not only a snowy midwinter day.
Like many medical concerns related to environmental factors, both hypothermia and frostbite are preventable with attention to detail during wilderness travel. Adventuring safely in cold conditions requires adding a few gauges to monitor on the mental instrument panel. Below, we’ll define hypothermia and frostbite and cover prevention and treatment of each in detail.
Hypothermia is the condition in which the body loses heat faster than it can produce heat, causing the body’s core temperature to drop to a dangerously low level. Hypothermia happens on a continuum from mild to severe. Severe hypothermia is a life-threatening condition.
Signs and Symptoms of Hypothermia:
Frostbite is damage to tissue due to freezing. It happens most often on the extremities: fingers, toes, the nose, and ears. Signs and symptoms of frostbite differ according to the severity of the damage; like hypothermia, it occurs on a continuum.
Signs and Symptoms of Frostbite:
Like many other risks we face while adventuring outdoors (heat-related illnesses, snakebites), smart decision making goes a long way toward preventing cold-related emergencies, and it is much easier to prevent these emergencies than treat them in a wilderness setting. The human body is more susceptible to hypothermia and frostbite when dehydrated, under-fueled, and tired, so simply eating, drinking, and resting diligently are critical steps in avoiding hypothermia and dehydration.
Moisture is a major factor in the development of cold-related emergencies. Buck Tilton, Wilderness EMT and author of Wilderness First Responder, explains, “Although you may think cold is the dominant environmental factor in hypothermia, it is the combination of cold and wet that poses the greatest threat.” To avoid this dangerous combination of wet and cold, proper layering for winter activities is essential. On a winter adventure, it’s important to wear enough layers to stay comfortably warm while avoiding overdressing that leads to sweating. Achieving this delicate balance can require adjusting layers frequently. Remove a layer as you warm up, and immediately add a layer when you stop for a break. Even though we can be comfortable while moving with damp, sweaty base layers, as soon as we stop, these damp layers put us at risk for hypothermia.
Another important moisture management tool is wearing the right fabric. Cotton dangerously retains moisture and keeps you cold when wet, contributing to heat loss through conduction. Avoid cotton! Choose synthetic or wool layers instead.
Constricting footwear adds to the risk of both hypothermia and frostbite. Often our efforts to keep feet warm by wearing thick or multiple pairs of socks contribute to foot sweat, and excess sweat means dangerous moisture around a vulnerable extremity. Be sure your boots have ample room in the toe box for toes to wiggle, and avoid thick socks that keep toes sweaty. Instead, choose a more insulated boot. Cramped toes suffer from reduced circulation and are more susceptible to frostbite.
When recreating in winter, carry the gear needed to respond to a cold-related emergency. Consider items like extra layers of clothing, a sleeping bag, a stove and fuel, extra food, sources of simple carbohydrates like sugary drink mixes, something to insulate a patient from the cold ground, hand warmers, and something windproof and waterproof like a small emergency bivvy. Think about everything you would need to avoid hypothermia and frostbite during an unplanned overnight in the backcountry or to treat a hypothermic or frostbitten patient.
On an overnight winter trip, be sure to go to bed warm and dry. Let feet dry completely, then put on a dry pair of socks.
When traveling in winter, always bring a windproof and waterproof outer layer, even on sunny days. Be sure you have a way to protect even your extremities from wind and water; remember the details like a shell jacket with hood, wind and waterproof gloves, and gaiters to keep snow out of your boots.
The guiding principle for treating patients in any stage of hypothermia is to remove them from a cold, wet environment and move them to a warm, dry one. While following this guiding principle, there are specific treatment considerations for each stage of hypothermia.
Treatment for frostbite involves gently rewarming the affected area and, if necessary, evacuating the patient. There are specific treatment considerations for each stage of frostbite, but while treating any stage, avoid two common mistakes. DO NOT massage cold tissue to rewarm it, and DO NOT place the damaged tissue near a source of radiant heat, like a fire. Both of these practices can worsen tissue damage. No matter the stage, it is critical to prevent the affected area from refreezing.
Even when not exposed to sub-freezing temperatures, tissue can suffer damage due to prolonged exposure to cold and usually wet conditions. This type of injury is known as nonfreezing cold injury (NFCI), immersion foot, and trench foot. Like hypothermia and frostbite, this injury occurs on a continuum from mild to severe and typically begins with skin that is cold to the touch, numbness, swelling, and white or bluish skin. Upon rewarming, the damaged tissue often looks red and swells. The patient may feel painful tingling, and blisters may form. Treat NFCI according to the same principles as frostbite, rewarming and administering aspirin or ibuprofen for pain. Wash and dry the foot thoroughly.
Avoiding hypothermia and frostbite is much easier than treating it. Simple yet easy to neglect practices protect against both conditions: hydrating well (keeping urine very light in color), snacking often, and minimizing fatigue. At the first sign of hypothermia or frostbite, stop and mitigate. Shivering? Remove damp layers and put on dry, warm clothing. Make a warm drink and eat a snack. Losing feeling in your toes? Loosen your snowshoe binding or micro spikes strap and rewarm those toes. Stopping and mitigating signs and symptoms of hypothermia or frostbite is time consuming, but letting mild hypothermia or superficial frostbite progress to a more severe stage is far more time consuming and life threatening.