Understanding and Avoiding Frostbite

The wilderness often requires us to push ourselves, but it’s important to know our physical limits. I learned this lesson the hard way and it literally cost me a million dollars.

What is Frostbite? Frostbite is a cold-related injury in which body tissues in the affected area freeze. Similar to burns, there are multiple levels of frostbite based on the varying degrees of cell damage. Frostnip is the first stage of the condition, followed by superficial and deep frostbite.

Frostbite can affect any part of your body that’s exposed to extreme cold for too long. Extremities such as ears, nose, cheeks, fingers, and toes are the most susceptible. When subjected to cold, blood vessels throughout the body constrict to preserve heat, so the body prioritizes keeping the core warm over the extremities. That’s why they’re more likely to be frostbitten.

With frostnip, the temporary near freezing of tissues, the skin turns red, becomes cold to the touch, and can start to go numb. Detecting changes in color may be more difficult in darker-skinned individuals. If you warm the skin soon after there will be no permanent damage. If you are experiencing frostnip, continued exposure to cold can result in the next stage: superficial frostbite.

With superficial frostbite, ice crystals begin to form within the skin as it freezes. This injury will cause permanent damage to the tissue affected. At this stage, the skin may feel warm and stinging. The skin may also appear white and fluid-filled blisters can appear.

With deep frostbite, also called full-thickness frostbite, the skin can feel numb again. Large blisters will form, and the tissue often will turn black and hard as it dies.

With superficial and deep frostbite, you do not want to re-warm the skin if there is any chance of the tissue refreezing.

What to Do if You Get Frostbite If you experience frostnip, re-warm your skin as soon as possible. Beware of re-warming near a fire. It’s difficult to tell if you are burning yourself if the affected area is numb. It’s safer to warm your hands or feet in armpits or on the stomach of a friend. If you’re alone, get inside a sleeping bag with a hot water bottle or a hot rock. Make sure to wrap hot objects in wool so as not to burn yourself.

If you’ve made it into frostbite territory and there’s a chance the damaged tissue will re-freeze, then you shouldn’t re-warm the injury. The freeze-thaw process results in compounding damage that exacerbates the problem.

Re-warming in the field is often difficult because the correct process requires immersing the affected area in a container of water at a recommended water temperature of 98.6 to 102 degrees Fahrenheit. In most cases, the best thing to do is to get out of the field and deal with the cold injury in a controlled environment.

How to Prevent Frostbite The best ways to prevent frostbite may seem obvious: dress properly and stay warm. But this can be easier said than done. Shifts in weather, vehicle mishaps, navigation errors, and other unexpected circumstances can result in longer-than-anticipated exposure to the elements. With that in mind, here are a few tips to prevent frostbite.

Stay hydrated and stay fed. Dehydration and lack of calories reduce the body’s ability to circulate blood. Decreased circulation makes it harder to keep blood moving to the extremities, and less blood in the extremities means less warmth. So, drink lots of water and eat nutritious snacks to protect the most vulnerable areas of your body.

The windy and dry conditions common with cold weather make frostbite more likely. These circumstances accelerate transepidermal water loss that cools and dries your skin. Have a neck gaiter you can pull up over your nose and cheeks and make sure you have a good hat that covers your ears. Protect as much of your skin from the wind as you can.

On winter backcountry trips, I like keeping hot rocks in my pockets to warm my hands. Those “Hot Hands” packs work well too. Even if you don’t want to make a habit of using such items, they’re good to have in your everyday winter kit. Wind-milling the arms is a good way to get the blood flowing back into your hands.

In my experience, the feet are the hardest part of the body to keep warm. Survival depends on the core staying warm, so our bodies direct all their efforts to do that. We can live without a foot, but not without a heart. Feet are usually trapped inside boots, making the regulation of temperature more difficult.

Socks: In the winter, socks and shoes are equally important to get right. If you don’t already, start wearing wool socks and don’t look back. Wool is my choice for socks, glove liners, neck gaiters, base layers, pretty much everything—except for a waterproof layer, obviously.

Depending on the situation, I’ll wear two pairs, or even three for extremely cold conditions. Always carry extra socks and change them out. At the end of the day, put on dry socks. When you get back to the vehicle at the trailhead or back to camp, change them. Our feet sweat, so there will almost always be moisture in our socks. For overnights, always have socks that are dry and reserved for sleeping. For extended stays in the wild, make sock drying a priority.

Do not wear socks, shoes, long underwear, or anything that’s too tight. It’s really important to let your blood move. Any restriction of circulation creates a vulnerability to cold injuries. If you are doubling up on socks, make sure they are two different sizes that layer over each other comfortably and loosely.

Boots: Make sure your feet have room inside your boots and you can wiggle all your toes. Ill-fitting shoes can increase your chances of acquiring frostbite. Compression of the toes restricts circulation and reduces the insulative properties of socks.

For longer stays in the backcountry, boots you can dry in the field are an absolute must. I won’t buy a winter boot that doesn’t have removable liners, and wool felt liners are the best. Wool liners allow you to dry them by the campfire or wood stove without worrying about damage.

My favorite winter boot is mukluk-style footwear. I appreciate the spaciousness of the foot box, the lack of heel, and the barefoot-like feel. There are mukluks made for both dry and wet conditions. "Dry" mukluks are made from breathable materials that allow moisture to escape, a crucial component for happy feet. "Wet" mukluks sacrifice some breathability, but they’re worth it if you’ll be walking in puddles or wet snow.

In addition to the above-mentioned foot care, I like to “smoke” my feet. Around the morning or evening fire, I make sure to hold my feet in the smoke of a campfire and dry them out before putting socks on.

Mental Attitude There are tons of tips and tricks to help you prevent frostbite. But perhaps the most important factor is attitude.

It’s easy to override what our bodies tell us and keep going. This is how I ended up with frostbite on my toes. I was on the History Channel show “Alone,” surviving in the backcountry and competing for a million dollars. It was December and I was in the Northwest Territories living off the land, eating rabbits and tracking porcupines. I was out for the day doing what I had to do to survive: gathering firewood and checking my trapline. I could feel my toes were uncomfortably cold and then numb. I knew I had just a few hours of daylight left and I wanted to use them, so I figured I’d warm my feet up after it was dark. By then it was too late; the damage was done. The medical team had to extract me from the situation to prevent further injury, dashing my hopes of winning the competition and a whole lot of money.

Don’t be the tough guy or girl and ignore numb fingers and toes. Stop and warm them up. Accidents do happen and it is possible to find yourself in a situation in which warming up is not an option. If there’s a choice, choose it. It’s not worth permanent damage that could keep you from enjoying the outdoors in the future. Even if frostbite doesn’t result in amputation, permanent damage can occur. Frostbitten tissue is permanently sensitive to cold and future frostbite injuries. You will have to be even more diligent in the care of your body in cold weather. Frostbite injuries forever change how you enjoy winter.

When tracking an animal, it is necessary to pay close attention to details and changes on the land. We must use all of our perceptive abilities to navigate the landscape. It is equally necessary to turn our awareness inward. To thrive we need to listen to the signals our bodies give us. Frostbite taught me that self-care is a survival skill.

Until next time, may your fingers be fatty and your toes be warm.