Altitude Sickness

Hardly something to worry about in the UK but altitude sickness can be a serious problem when you start to go over around 2500m or 8000ft.

What is altitude sickness?

Altitude sickness is caused by the effects of low pressure ( usually due to high altitude). The mildest form of altitude sickness is Acute mountain sickness (AMS) which is essentially headache and nausea at about 3000m or more and is a benign illness.  AMS can however progress into high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE). These are both serious life threatening conditions.

Signs & Symptoms

Altitude sickness symptoms can include the following;

• Headaches
• Loss of appetite
• Fatigue
• Shortness of breath
• Disturbed sleep
• Nausea and vomiting, increasing weakness and fatigue
• Decreased co-ordination
• Decreasing mental awareness

What causes altitude sickness?

The body’s muscles and organs need an adequate supply of oxygen to function properly. As altitude increases, the percentage of oxygen in the air remains constant but the pressure decreases, meaning we breathe in fewer oxygen molecules with each breath.

This leaves the body short of its requirements and causes altitude sickness.

How do you treat it?

In mild cases of AMS, rest, fluids  and painkillers will help treat the symptoms and allow the body to acclimatise. However no further ascent should be attempted until all the symptoms have disappeared.

Descent to a lower altitude is necessary if the symptoms are more severe. If this does not help then hospital treatment may be necessary.

Another solution is an inflatable pressure bag that is large enough to fit a person inside known as a Gamow Bag is also sometimes used. By inflating the bag with a foot pump, the effective altitude can be decreased as much as 1500 meters

How to avoid altitude sickness?

Alitude sickness can usually be avoided with good preparation and following advice

• Good physical fitness
• Drinking plenty of liquid
• Not ignoring symptom of AMS when they occur
• When you get past past 3,000 metres, do not ascend more than 300 metres per day to sleep. You can climb as high as you want, just make sure that you come back to sleep no more than 300 m higher than your previous night’s elevation.
• Acetazolamide (Diamox) has also been used as to decrease the symptoms of altitude sickness. You should only take this medicine after consulting a doctor. It’s not a substitute for common sense and you should descend immediately if your symptoms of altitude sickness get worse.

Remember this is just a short overview so if in any doubt you should always seek professional medical advice.