IAMAT |International Association of Medical Assistance to Travellers| IAMAT |International Association of Medical Assistance to Travellers|

Country Health Advice Kenya

General Health Risks: Altitude Illness

Travellers climbing Mt. Kilimanjaro (5790m / 18996ft) and Mt. Kenya (5180m / 16994ft) are at risk.

Description

Altitude Illness occurs as a result of decreased oxygen pressure at high altitudes. The illness is divided into three syndromes recognized by a cluster of symptoms arising from rapid ascent to high altitudes, especially more than 2400m / 7874ft.

Risk

Altitude Illness can occur to anyone at any time regardless of physical fitness. All non-acclimatized travellers, including children, are potentially at risk of developing altitude illness which depends on level of exertion, speed of ascent, altitude reached, humidity, oxygen, and air pressure levels, as well as personal susceptibility. The human body is able to acclimatize to high altitude but must be given time to do so, ideally 3 to 5 days.

Acclimatizing to high altitudes:

  • Your ascent schedule should include rest days and flexibility in case you need to slow down and adjust to the new altitude. A gradual ascent to high altitude over a few days is ideal. If this is not possible, make sure to allow extra time to acclimatize: 1 day for every 1000m / 3280ft.
  • Avoid strenuous exercise for the first two days and avoid all alcoholic beverages for the first few days.
  • Set a reasonable pace, avoid overexertion, and keep hydrated. Do not overload yourself with extra gear. If you are camping at high altitudes, ensure that there is good ventilation when using camp stoves and heaters in confined spaces.
  • Consult with your healthcare provider if taking acclimatization medication is appropriate for you.
  • Persons with pre-existing health conditions such as angina, heart failure, pulmonary diseases, and diabetes should consult with a high altitude medicine specialist before travelling to mountainous areas.
Symptoms

The first syndrome, Acute Mountain Sickness (AMS), is characterized by headache, fatigue, loss of appetite, nausea and sometimes vomiting, dizziness, insomnia and disturbed sleep appearing 2 to 12 hours after arrival at high altitude. Symptoms usually disappear within 24 to 72 hours as the body acclimatizes to the altitude. If AMS symptoms persist, rest and acclimatization medication is needed. Do not continue to ascend to a higher altitude if symptoms persist. If there is no improvement descend to a lower altitude, by at least 300m / 984ft.

In rare cases AMS progresses to the second syndrome, High Altitude Cerebral Edema (HACE), which is characterized by worsening AMS symptoms, drowsiness, confusion, staggering gate and ataxia (lack of voluntary muscle coordination). Immediate descent to lower altitude is important since developing HACE symptoms can be life threatening if untreated immediately. HACE is rare at altitudes below 3600m / 11811ft.

The third syndrome, High Altitude Pulmonary Edema (HAPE), affects the lungs and is characterized by increased breathlessness with exertion progressing to breathlessness during rest, a dry cough, chest tightness or congestion, rapid heart beat, general weakness, and blue / purple skin tissue coloration. Developing HAPE symptoms can be life threatening if untreated. Immediate descent to a lower altitude and administration of oxygen are imperative.

Immediate descent, combined with medication (and oxygen, if available), is the best treatment for severe AMS, HACE, or HAPE. Consider evacuation if necessary.

Prevention
  • Plan your ascent over several days to ensure proper acclimatization (at altitudes of more than 2400m / 7874ft, ascend at a rate of no more than 300m / 984ft per day). 
  • Learn about the symptoms before you go and heed the warnings when symptoms appear. 
  • Do not continue to higher altitude, especially to sleep, when symptoms appear even if you feel they are minor. 
  • Descend to a lower altitude (at least 300m / 984ft) if symptoms persist while resting at your current altitude.

Health risk description last reviewed: September 19, 2016
Country information last updated: September 19, 2016


Sources

  • Litch JA, Bishop RA. Altitude Illness. In: Jong E, Sanford C, eds. The Travel and Tropical Medicine Manual, 4th ed. Waltham: Saunders Elsevier; 2008: 152-163.
  • Altitude.org: Altitude Sickness
  • Centers for Disease Control and Prevention: Altitude Illness
  • International Society for Mountain Medicine: Acute Mountain Sickness



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