Altitude sickness is a series of signs and symptoms which may occur when a person climbs or is taken to a high altitude. It can affect different people in a variety of ways ranging from mild headaches to sudden death. Both male and female can succumb rapidly, and the condition can be seen at any age. The effects of the low oxygen levels experienced at altitude can be devastating and frequently fatal in the unprepared.
Causes of Altitude Sickness
The primary condition which occurs is the change in the available oxygen concentration. This makes the body work harder to maintain the necessary levels of oxygen for the cells At sea level the normal oxygen concentration is 21%. At 12,000 ft the amount of oxygen is reduced by 40% and so breathing rate and cardiac activity need to increase to compensate for this deficiency. Unfortunately, many of those affected by the condition still push onward despite warning signs and the body just cannot cope.
Altitude sickness can affect different people in a variety of ways ranging from mild headaches to sudden death. Both male and female can succumb rapidly, and the condition can be seen at any age. Those with hypertension, chronic lung disease, atherosclerotic disease, past history of blood clots, epilepsy, sickle cell anaemia etc. Those who disregard the very serious and regularly fatal risk of ascending without due care to high altitude!
Frequently the deaths which occur are in the younger age group who tend to disregard the early warning signs.
Symptoms of Altitude Sickness
Symptoms of altitude sickness vary but include the following
- Nausea
- Yawning
- Slow Response to Questions
- Lack of Concentration
- Weakness
- Significant headache
- Breathlessness
- Loss of appetite
- Dehydration
- Disturbed sleep
- Dizziness
- In coordination
If you think a member of your party may be developing altitude sickness, ask them to walk along in a straight line. This is a very simple test for in coordination.
Avoiding Altitude Sickness
If you have to arrive at a high destination such as Quito – 9500ft, Nairobi – 6000ft, La Paz – 13,000ft, or Bogota – 8,600ft, to avoid altitude sickness, try to ensure that you have no energetic plans for the first few days. Avoid alcohol and make sure you rehydrate yourself sufficiently. Always split into small groups, perhaps 3 or 4, who can look out for each other all the time. Any peculiar symptoms should be reported to the trip leader immediately and should be taken very seriously.
Always remember altitude sickness can be rapidly life threatening and must be always considered a risk in those at altitude. The main form of therapy is to descend as soon as possible and only to ascend again once full acclimatization has occurred. This usually means going down by at least 300 to 600 ft. and remaining there for the necessary time. This can be up to 3 days.
Two main tablets can be used to help with avoiding altitude sickness; Diamox (Acetazolamide) is a Sulpha drug which increases respiration to help metabolise more oxygen and should be started at least 24 hours before ascent and maintained for about 3 to 5 days when at high altitude; Dexamethasone (a steroid tablet) is occasionally used to lessen the risk of brain swelling.
For more information please see travel health advice – avoiding altitude sickness