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What Happens When Clothing Fails
If people find themselves ill prepared to keep warm in a polar climate three outcomes are likely:
- Hypothermia
- Frostbite
- Snow blindness
Explorers who have not been well equipped have died due to a combination of the effects of hypothermia and frostbite and so adequate clothing is vital when travelling in the polar regions.
Hypothermia(top)
The average body temperature is around 37°C. The body has a number of ways to keep itself at its vital temperature; falling even a couple of degrees below this can have very serious consequences, as many of the body’s chemical reactions central to survival can only occur within specific temperature ranges. When a body’s temperature is lower than 35°C it is in the early stages of hypothermia. At this stage a person will shiver to try and generate heat. The blood vessels will contract to prevent warm blood reaching the surface; it will also reduce blood flow to the extremities to prevent the loss of heat. As the body becomes colder it will try to release more energy to heat the body and to power the action of shivering, the metabolic rate will increase and food will be used up more quickly - obviously this is problematic if food is in short supply. Once these mechanisms of maintaining and increasing heat are overwhelmed and the loss of heat is greater than heat production, the body is suffering from hypothermia.
A person suffering from hypothermia is likely to have a slow breathing rate and low blood pressure. They are likely to feel tired and may become argumentative, but are unlikely to realise this is a warning sign of the onset of hypothermia. Blood will be cut off to the extremities making them numb, the sufferer will then have problems undertaking dexterous tasks such as fastening up clothing and so they may not bother which in turn will make the hypothermia worse. A victim of hypothermia is likely to be stumbling, very sleepy and suffering from confusion. People with hypothermia are often unable to make rational decisions, for example they may lie down in the snow for a rest when they really need to keep moving. This is obviously very problematic when out in the field.
As the hypothermia worsens the heartbeat will become irregular and the pupils will become dilated, giving the victim the appearance of being in a coma. Once a person is in such a situation they need to be warmed up. Severe exposure can normally be treated only in hospital, which is difficult for a polar explorer. For milder cases of hypothermia an explorer can recover by being warmed up in a tent with hot drinks and blankets.
Frostbite(top)
Frostbite can attack any part of the body, but it usually affects exposed areas such as the face, hands or feet. It can attack very suddenly with the sufferer feeling as though a wasp has stung them. It can be recognised by white patches appearing on the skin. Frostbite will initially present as a feeling of intense coldness, eventually replaced by numbness.
Frostbite occurs when the temperature of the skin falls below its freezing point, which allows ice crystals to form within the skin’s cells, killing them. When the skin is re-warmed the skin will swell and blister and these purple and black blisters will harden. For superficial frostbite these areas can be removed to reveal a layer of new skin beneath.
A more serious frostbite will extend the damage below the layers of skin to the muscle and bone. This almost certainly results in permanent tissue damage. There is no cure for such damage and many explorers have had amputations, especially of fingers and toes but also parts of arms and legs.
Frostbitten skin needs to be warmed up to aid the recovery process. However, it should not be warmed up if there is a possibility it will re-freeze. A continual thawing and freezing of the skin will cause greater damage. Today, medical guidelines suggest a person should be taken straight to hospital where they can be warmed up. For explorers in the polar region this poses a particular problem. It can be difficult to thaw skin out quickly enough or prevent it refreezing.
It is quite common for frostbite and hypothermia to occur in conjunction. If a person is suffering from hypothermia, this should take precedence in treatment as saving the victim’s life is more important than saving a frostbitten area.
Snow Blindness(top)
Snow blindness is a painful eye condition caused by overexposure to ultraviolet rays (UV). These are strong in intensity at the poles due to their high elevation. Light is also highly reflected as snow and ice have a high albedo (reflectivity property).
Snow blindness can be considered sunburn of the cornea of the eye; like sunburnt skin it can take a few hours to realise what is happening. Eyes suffering from snow blindness tend to be bloodshot and teary, sufferers will complain of feeling grit in their eyes and their eyes may swell shut. Moving the eyes or blinking can become extremely painful. Often snow blindness will result in temporary blindness, but at its most severe this can be permanent.
To treat snow blindness the eyes should be bandaged or covered with cloth, this prevents further irritation from light or the movement of eyelids. The eyes need to rest to allow the healing process. Today drops are used to speed up the healing process. In years gone by ophthalmic cocaine (of a different chemical composition to recreational cocaine) would be dropped into the eye to assist healing. Polar explorers often do not have the liberty to rest for a few days and so have been known to man-haul their sledges blindfolded with their companions directing them.
To prevent snow blindness, the indigenous people of the north would wear goggles. These consisted of an eye mask with a long thin slit to allow in a limited amount of light. Polar explorers in the heroic age would develop many types of snow goggles. Initially using goggles modelled on Inuit design, Scott and his crew on Discovery also experimented with types containing coloured glass, often green, to reduce the brightness of glare from the snow. In addition, tents were often made out of a green fabric to give the eyes a rest from the whiteness. Today, explorers, scientists, visitors and indigenous people wear sunglasses suitable for the polar climate; these are very similar to the glasses worn by skiers.
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