Frostbite, medically named cryopathy, sets in when the body is exposed to temperatures of, or below, 0 deg C / 32 deg F. The effects can be seen most commonly in the fingers, toes, chin, cheeks, nose and earlobes, but it is actually the skin tissue and blood vessels of these extremities which are damaged. Surprisingly, frostbite does not only set in at high altitude. It can occur in comparatively low temperatures as long as the wind chill factor compensates. This fact could account for a large number of frostbite cases where climbers are convinced that the numb feeling they are experiencing couldn’t be frostbite because not only do they not feel cold, but climbers often have numb limbs for periods of time. It is always wise to take a small clip-on thermometer.
The speed at which the condition develops depends entirely upon weather conditions and the duration of exposure to those conditions. Frostbite can arise little by little or progress through its three stages at an alarming rate. Frostnip, the primary stage, causes the skin to turn white, become soft to the touch, and the individual will feel a pins and needles type sensation. However, these symptoms are quite reversible, and can be treated simply by flexing the fingers and toes, stamping the feet, clapping hands, placing them in the armpits or groin, breathing warm air on the affected area, or in more extreme cases by immersing in warm water.
The second stage, superficial frostbite, can be distinguished from frostnip as blistering may now occur. The area will be a yellowish-grey in colour and will feel waxy or leathery as the skin is still flexible despite the microscopic ice particles forming in the skin cells. It is also characterised by severe pain when the affected area becomes re-warmed.
If superficial frostbite is left untreated then deep frostbite can develop. Setting in at around -10°C/14°F deep frostbite far more serious and the risk of permanent damage, including blood clots, gangrene, and loss of limbs, is increased. This is because the extreme temperatures have the power to freeze blood vessels, muscles, tendons, and even bone. An individual might not even realise that his or her condition has progressed to this stage because when nerves become frozen the feeling is lost to that area. If observed the tissue will be hard and white, and has the texture akin to a frozen piece of chicken. Despite the high risk of losing limbs it is not uncommon for a near-full recovery to be made if proper medical attention is obtained.
During recovery a frostbite site will swell and huge blisters are likely to form. It is best to leave these well alone. They will eventually shrink back to normal size but will leave discoloured tissue and signs of gangrene may arise. This covering eventually breaks away and, assuming frostbite was superficial, leaves new pink, shiny skin. If it was deep frostbite then the limb or affected area will simply fall off. By this stage the nerves are so damaged that the process is not painful. Although almost impossible to gauge the outcome in the first few weeks after frostbite, amazing recoveries do happen. For this reason any kind of surgery is usually best avoided for a good while, until it is clear that it is the only option.
The symptoms caused by frostbite are likely to make a climb very difficult and so if a party member becomes ill this usually means abandoning a climb. Furthermore, frostbite will often put its victim out of action for a few months at least.
Certain people are more at risk of developing frostbite than others. As always, the elderly and young are particularly susceptible. Additionally, people with circulation problems, a history of previous cold injuries, those who regularly take particular drugs (such as alcohol, nicotine and beta-blockers) and those with recent injuries or blood loss are at an increased risk.
Preventing frostbite is easier than treating it, and this can be done in a few ways:
- Wearing adequate layers of clothing to trap air between them will help to maintain heat around your body and allows perspiration to evaporate, so lessens the risk of frostbite. Layers are better than one bulky jumper because not only do they trap air but allow for ventilation. For the cold, it is advisable to wear wool or polyester substitutes. Water-repellent layers are also good, but not waterproof as they trap perspiration. Down is a warm material too but when it gets wet it becomes heavy and loses much of its warmth. Also, ensure that clothing is not too tight as it may decrease warming blood flow to frostbite-vulnerable areas.
- Bring spare gloves and dry socks. Wear two pairs of socks at a time – wool is preferable. Ensure boots are not too tight and
if using plastic boots, carry spare inners. Make sure the boot is high enough to cover the ankles. With gloves, mittens are often warmer but allow less hand movement.
- Limit, or if you can, completely cut out alcohol and tobacco. Alcohol triggers an internal rise in body temperature, causing the body’s temperature regulator to dilate blood vessels in order to cool it down. For obvious reasons, losing heat on a mountain is not advised. Conversely, tobacco constricts blood vessels, particularly the tiny capillaries which take blood to the body’s extremities, and so increases the risk of frostbite.
- Unnecessary exposure to the cold should be avoided – keep warm and out of the wind. When you have to go outside, try to cover as much of the body with protective clothing such as scarves, hats and gloves. The areas you cannot cover can still be protected using a waterproof moisturiser.
- When either exhausted, wet or under the influence of alcohol or certain drugs do not prolong time spent outside.
If the individual cannot be taken to a hospital immediately then help can be administered in the following ways:
- Depending on the severity, it may be necessary to move the individual to a lower altitude where help is easier to reach and the temperature is lower.
- Bring him or her inside and cover the area in warm water for sessions of 20 minutes.
- Alternatively, soak a piece of cloth in warm water and gently place it on the area.
- Do not use dry heat, such as a fire or heat pads because without sensation the area is likely to burn causing more damage.
- It is imperative that hot water is not used, that the area is not knocked or rubbed and that any blisters are left well alone.
- Keep the area raised and well away from any heat or sharp objects as because feeling is reduced the area may be injured further.
- Thawing may be excruciating, but perseverance is paramount. Once this is done, wrap carefully in clean bandages, ensuring that fingers and toes are separated. Those around the affected person may need to feed and clothe them to ensure the area is not used.
- Above 5000m oxygen should be given.
- Keep the skin clean after re-warming to avoid any infection.
- Do not thaw an area is you cannot guarantee that it will not re-freeze. Thawing and refreezing will can more damage than leaving an area frozen.
Seek professional medical attention if you spot any of the following signs:
- Skin swelling
- Skin colour change
- Skin texture change
- Loss of limb movement
- Loss of limb feeling
- Loss of Memory