• Uncontrolled shivering followed by
• Confusion & dizziness
• Slow, clumsy movements and difficulty in walking
• The person feels tired
• Breathing becomes shallow and pulse becomes slow
• Loss of consciousness

Treatment of someone suffering from hypothermia entails preventing any further drop in body temperature. This involves seeking shelter, insulating and protecting them from the cold environment. Replace any wet clothing with dry ones. Make sure the head, feet and hands are covered. Place the person in a sleeping bag with another person. Give them warm drinks and high energy foods (sweets, chocolate etc.) Avoid rapid re-warming unless the victim is well and conscious.

Chilblains (non-freezing cold injury) occur in cold, damp conditions where the hands and feet are cold (and generally wet) for extended periods. They are characterised by itchy or painful swellings that can lead to open sores if left untreated.

Frostbite is freezing of the skin and surrounding tissues and can occur in anyone exposed to temperatures below freezing without adequate protection. Frostbite should never be defrosted if there is a likelihood of re-freezing as this will greatly exacerbate the problem.

Prevention of these conditions is achieved by maintaining adequate insulation from the cold by the use of appropriate clothing, keeping the extremities warm and dry and by consuming high energy foods and warm drinks.

Being attentive to early signs and symptoms is important. If frostbite is suspected the casualty should be referred for medical help as soon as possible.

ALTITUDE

The problems associated with high altitude are usually only manifest in people who have been to altitudes in excess of 3,000 metres (10,000 feet).

The main concerns associated with high altitude include:-

Cold: is a factor generally experienced at altitude. As a rule, the higher you climb, the colder it gets. The risks and precautions that need to be taken with regard to the cold are covered in the previous section.

Dehydration: It is very easy to become dehydrated at high altitude due to the dryness of the air and by water loss in sweat caused by exertion. In order to prevent dehydration, it is important that you drink as much fluid as you can while in the mountains, (about 3 litres per day). The best way to determine if you are getting enough fluid is by urine output. It should be colourless or pale yellow. If it is bright yellow or orange, you are not drinking enough.

Sunburn: At higher altitudes the sun's harmful ultraviolet rays are more concentrated. You must protect yourself against these rays by using sunscreens or sun blocks. You can also use hats, scarves and masks to protect your face and neck. Remember, even if it is not hot, you can get severely burned. For more information, see the section on exposure to the sun.

Snow blindness: Snow and ice both reflect ultraviolet rays. These rays can damage your eyes causing pain, watering and swelling and an intolerance to light. This condition is known as snow blindness and can be very painful. Fortunately it is short lived and recovery is usually complete after a few days. It can prevented by using adequate protection such as sun glasses or goggles.

Acute mountain sickness (AMS) is the term used to describe the most common symptoms which include; headache, nausea, dizziness, loss of appetite, vomiting and insomnia. If these symptoms are ignored and the affected person continues to ascend, more serious conditions such as High Altitude Cerebral and/or Pulmonary Oedema (HACO & HAPO) both of which are life threatening can result.

Avoidance of mountain sickness is best achieved by a slow ascent and by maximising the opportunities to acclimatise.

The appearance of any of the above symptoms should prompt consideration of a descent, or at least the decision not to go any higher until they resolve.

Continued symptoms should result in a shift to a lower altitude. By spending the night at a lower altitude than the highest attained during the day is helpful - Climb High Sleep Low.

Prophylactic acetazolamide has been effective in preventing altitude sickness in susceptible travellers, or when time for natural acclimatisation is limited but it does not protect against cerebral or pulmonary oedema.