Altitude Sickness

Altitude sickness has been reported as low as 6000ft/1800m; Acute Mountain Sickness (AMS) is more common and more severe at elevations greater than 10,000ft/3000m.

Acclimatization is the process by which your body adjusts to higher altitudes. How? By increasing rate/depth of breathing; increasing heart rate; a slow increase of red blood cells to carry oxygen.

How you adapt to altitude is not related to how fit you are; it seems to be more related to how well your breathingadapts to a higher elevation. AMS develops as a result of failure to adapt to higher altitude
How? Fluid accumulates in between the cells of the brain and/or lungs. Symptoms can be mild or severe.

Mild Symptoms of AMS

  • Headache
  • Loss of appetite
  • Nausea
  • Lethargy
  • Lack of sleep
  • Dizziness
  • Swelling of hands, feet, & face

What to do?

The symptoms area warnings that your body has reached its limit & needs more time to acclimate.

  • Do not climb/trek higher; most importantly, do not sleep at a higher altitude
  • Symptoms should clear in 24/48 hrs; if not, or you are getting worse at that altitude, DESCEND at least to the last altitude that you felt well
  • When you feel well again, you can continue higher
  • Ibuprofen (Motrin/Advil). Aspirin or Tylenol/Paracetamol can be taken for headache

Severe symptoms of AMS

Early symptoms can progress to severe symptoms.

  • Fluid filling the lungs is known as HIGH ALTITUDE PULMONARY OEDEMA or HAPE
  • Fluid found in the brain is known as HIGH ALTITUDE CEREBRAL OEDEMA or HACE.
  • HAPE symptoms include: breathlessness with exertion, then with rest
  • Cough, at first dry, then “wet” with pink, frothy sputum
  • Chest tightness
  • Extreme fatigue
  • HACE symptoms include: headache, usually severe
  • Decreased appetite
  • Nausea/vomiting
  • Mental confusion
  • Difficulty with balance/ coordination; can’t walk in a straight line
  • HAPE & HACE can occur separately or together

What to do?

  • DESCEND IMMEDIATELY! These are life-threatening emergencies; descent must not be delayed for therapy or because it is in the middle of the night. Get help in the form of porters or animals.
  • Do not leave someone with Acute Mountain Sickness alone or send them down the trail to descend by themselves. They must be accompanied by a healthy person.

Prevention

  • Recognize the early symptoms of AMS; if you feel ill at altitude & not sure why, assume it is AMS & act accordingly
  • Plan a sensible itinerary; have extra days built into your schedule to allow for flexibility
  • Do not trek more than 1000ft/300m a day in elevations greater than 10,000ft/3000m
  • Trek high; sleep low. You can go higher than 1000ft/300m per day; however, go back down to sleep
    If symptoms of AMS develop, rest at least 1-2 days; if not better or getting worse, descend
  • Stay hydrated & drink enough so that your urine is straw colored
  • High carbohydrate diet may help
    Diamox (acetazolamide) can be used to prevent and/or treat mild/moderate symptoms of AMS

JUDGEMENT IS AFFECTED BY ALTITUDE. IT IS EASY TO DENY THAT YOU OR YOUR FRIENDS ARE SUFFFERING FROM AMS. IT IS IMPERATIVE THAT DESCENT BEGIN IMMEDIATELY WITH THE ONSET OF SEVERE SYMPTOMS; DO NOT GO HIGHER IF MILD SYMPTOMS OCCUR.

For further detailed information on altitude sickness and acute mountain sickness please see the websites listed below:

http://wikitravel.org/en/Altitude_sickness
http://www.traveldoctor.co.uk/altitude.htm
http://www.yowangdu.com/tibet-travel/altitude-sickness-prevention.html