PDA

View Full Version : Altitude sickness


Marmot
26th October 2005, 01:27 PM
Acute mountain sickness commonly occurs with people travelling at altitudes in excess of 3000 meters. Is very unusal at altitutudes below 2500m.

Changes in the levles of oxygen and the leakiness of bloood vessels leads to a development of AMS.

For most altitude relates illness is unpleasant but usually settles in a day or two. In some cases AMS can progress to the life threatening high altitude pulmonary oedema (HAPE)
Sensible rates of ascent combined with drugs, such as Diamox makes these problems much less likely.

Acute Mountain Sickness symptoms
Headaches, loss of apetitite, nausea and vomiting, fatigue or weakness, dizziness or light headedness and difficulty xleeping.

These symptoms usually develop during the firs 6 - 12 hours after arrival at a new altitude and resolve over one to three days, providinf no further ascent is made.

Acclimatisation
The main risk for developing AMS is ascending too quickly. Above 3000 speed of ascent should be gradal. It is recomened that height gain be 3-600meters a day, with a rest on the 3rd day.
High altitude pulmonary oedema and high altitude cerebral oedema (hace) may develop if these precautions arent taken.

In HAPE fluid leaks from the tssue of the lungs causing breathing difficulty. In HACE fluid leaks into the brain causing it to swell.

HAPE = shortness of breath at rest, coughing - with blood, forthy phlegm and extreme tiredness.
HACE = worsening headaches, unsteady on the feet, changes in behaviour and drowsiness and will progress to a coma if untreated.

The faster the rate of ascent the more lilely and more severe the AMS will be. Individuals acclimatise at different rates. Thise who have developed AMS before are more likely to have the problem again. Over-exertion and dehydration make the development of AMS more likely.
4-6 litres a day should be drunk. Fitter people are not less likely to get AMS.

Medication can be taken to treat AMS, the most common being acetazolamide (Diamox), which is normally given in 125mg tablets twice daily.

Paracetamol or aspirin can be used to treat headaches, but most symptoms settle after a nights rest. if symptoms remain or worsen descent is the only option.

Hillwalker
5th September 2006, 01:00 PM
Just a couple of points Marmot. Acetazolamide (Diamox) doesn't 'treat' AMS, the only treatment is to descend. Diamox reduces the likelihood of onset slightly, but not enough to cloud the symptoms, and makes the hard work of climbing at atitude less unpleasant. HAPE and HACE are what affected people die from, and it still happens today (Kilimanjaro in July 2006).

There is a question over the use of Asprin, which some authorities believe to make a cerebral bleed more likely by thinning the blood. They would recommend an inti-inflammatory (Ibuprofen) or Paracetamol to treat headache. If this makes the headache bearable or resolves it then OK, if not - descend!