Ah, November. As the weather turns to biting cold, the warm days of the summer are just a memory. The future appears icy and wondrous. Geocaching in the winter months requires a change in attitude; a different strategy to plan and execute your hunt. For the next couple of months, we’ll review some of the problems a cold-weather cacher may encounter and both how to treat them and plan ways to avoid them. This month we will focus on Frostnip and Frostbite, and in December we will review Hypothermia.

Frostnip is nonfreezing injury of the skin tissues, usually of the fingers, toes, ears, cheeks, and chin. Numbness and tingling are present, but no tissue injury occurs. Symptoms occur when blood vessels supplying the affected tissues narrow because of the cold. This response occurs at temperatures about 59°F (15°C). Frostnip is the least severe form of frostbite, but should not be taken lightly.

According to Scott H. Plantz, MD (Assistant Professor, Department of Emergency Medicine, Mount Sinai School of Medicine), skin tissues with frostnip do not hurt. The tissues are soft, resilient (if you press, the skin indentation springs back), and may appear red, yellow, or gray. Full recovery is the rule. This is in contrast to frostbitten tissues, which may lose sensation, are cold, solid, pale, blue-tinged, waxy, and woodlike. The tissues are not resilient, and small blisters containing clear or bloody fluid may form.

Frostbite is destruction of body tissues due to freezing (at 0°C or 32°F). Ice crystal formation in the tissues breaks apart cells, thereby destroying the tissues. Some factors may contribute to this type of injury. They include dehydration, poor conditioning, wearing wet/tight clothing, malnutrition, altitude, or medical conditions of poor circulation (such as diabetes, heart disease, anemia, or sickle cell disease). Frostbite can strike in any season, especially in the high country. Keep a close eye on the weather wherever you go in the wilderness, and adjust your plans as necessary to avoid the risk of frostbite.

How to diagnose Frostbite

Recognizing the different degrees of frostbite is essential to treating it, and treating it may save a finger, toe, arm or leg.

• Check for sensation. Numbness might indicate frostbite. Look at the affected body part. If a very small area appears white and waxy or gray and mottled but feels normal to the touch, it probably has frostnip. Warm the affected area at once.
• However, if a body part has the appearance of frostnip but is hard on the surface and soft below, this is probably superficial frostbite.
• Check for yet more serious frostbite, indicated by a large discolored area - purple in the most severe cases - that feels hard all the way through.

Evacuate if you are outdoors, taking extreme care not to let the frostbitten body part refreeze. If you decide to evacuate, first strip the affected part of all clothing (unless frozen to the skin) and wrap it in as much dry insulation as possible. On the way out, do what you can to keep the affected part from refreezing along the way by changing how well the part is covered and adjusting your pace.

Frostbite is dangerous; do everything in your power to prevent frostbite before it occurs, but if you see any possible symptoms of frostbite, treat immediately by rewarming the affected area in a warm bath. Rubbing or manipulation should be avoided. Do not thaw until the person is in a warm environment. Thawing and refreezing will result in significantly more damage to the tissue. Frozen feet may be walked on if necessary. Once feet begin to thaw, avoid walking on them. Consider taking a pain reliever such as ibuprofen to brace for the inevitable pain of rewarming.

Treatment

Rewarming the injured area is all that is required to treat frostnip. Place the affected body part against another body part that is warm. For instance, if the cheek is frostnipped, place a warm hand against it; if a finger is frostnipped, put it in a warm armpit. Avoid rubbing because this can injure cold body tissues.

"Folk remedies," such as rubbing the affected part with snow, exposing the area to an open flame, or hitting the area (supposedly to restore circulation), may only make the injury worse. "Folk remedies," such as rubbing the affected part with snow, exposing the area to an open flame, or hitting the area (supposedly to restore circulation), may only make the injury worse. Don’t forget to get out of the cold as quickly as possible. Treating Frostbite is much more involved. For the rewarming process you will need:

Heat the right amount of water; enough to cover the affected area once it is in the receptacle to between 104 and 108°F. Pour the heated water into the receptacle and immerse the affected part - stripped of all clothing and covering - in the water, taking care that it doesn't touch the sides of the receptacle. Heat more water, again to between 104 and 108°F. Replace the water in the receptacle once it has cooled to below 100°F. Repeat the heat-and-replace cycle until all discoloration has disappeared and all tissue is once again soft and pliable. This usually takes 30 to 60 minutes. Prepare a bath of water mixed with antibacterial soap. Immerse the affected area for five minutes to minimize risk of infection. Air-dry the injured area, gingerly apply aloe vera ointment and cover the area gently with dry sterile gauze and insulating layers.

Prevention

Prevention is the best medicine. Avoid tight-fitting clothing, including footwear, which might impair circulation. Avoid alcohol, which could contribute to dehydration and impair judgment. Avoid caffeine and nicotine, which constrict blood vessels and therefore reduce the blood supply to extremities.

Many people invite disaster when selecting winter clothes. Not wearing a hat is the number one mistake. Layer clothing for maximum warmth and convenience. Layers allow you to add and remove items as your body temperature rises and falls.

• Begin with a base layer of polypropylene underwear, top and bottom. You can purchase these inexpensively at many outdoor stores. Brand-name items don't always deliver better quality, despite their higher costs.
• Add one or more fleece layers as dictated by your comfort range. Again, these needn't be expensive to provide effective warmth. A vest is a good option, paired with a long-sleeved layer.

• Add an outer waterproof, breathable shell (with outer layers, more money usually does buy better quality). This layer does not need heavy insulation unless you expect to encounter below-zero temperatures. For jackets, get something that extends below your waist and has a hood.
• Pants should be loose-fitting and should rise above your waist to keep out snow. Look for sealed seams and elastic or drawstrings at cuffs and hems.
• Wear a hat that completely covers your head, or even one that has earflaps, to prevent a potentially life-endangering loss of body heat. Look for itch-free fleece headbands on warm wool hats.
• Waterproof, gauntlet-type gloves that extend over your jacket's sleeves provide the most protection from snow and water. Some people's fingers stay warmer in mittens.
• Boots present the biggest challenge for the novice winter recreationist. The most successful boot design incorporates a rubber lower boot with a leather top and removable felt liner. Boot temperature ratings are particularly important if you will be outside for long periods of time and need your feet to stay warm.
• Accessories should include: lip balm, hand-warmer pads, sunglasses and sunblock.
• Finally, don’t forget to drink lots of water; most people don’t realize how quickly they dehydrate while exerting themselves in cold weather.
Disclaimer: This information is not intended as a substitute for
professional medical advice or treatment.

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