Trekking is generally very rewarding and a lifetime experience. While trekking is not dangerous, health and safety should always be kept in mind. Whether you're going for the Everest Base Camp trek in Nepal, the Inca Trail in Peru, or wanting to trek Kilimanjaro in Africa, all tour companies on Bookmundi will always have been carefully selected, to ensure that you get an as good and safe trekking experience as possible. We still recommend, however, that you always prepare yourself as much as possible and go through the below information on health, safety and altitude sickness while trekking. They may come in handy.
Altitude illness also known as altitude sickness is a pathological effect of high altitude on humans, caused by acute exposure to low pressure of oxygen at high altitude. Should it occur it will often be above 8,000 ft and may manifest itself in either AMS – Acute Mountain Sickness, or the more serious conditions HACE and/or HAPE. Altitude illness should always be taken serious as ignoring it may ultimately lead to death. In most instances, however, listening to the body and taking the necessary preventative measures, as outlined below, will entirely prevent AMS from occurring, or remove it, if occurred.
It is a result of lack of oxygen. While the atmosphere will always have 21% oxygen the driving pressure decreases the higher we go. At sea level the driving pressure forces sufficient oxygen into the capillaries of our lungs giving saturation of oxygen in the blood and throughout the tissues. However, as we start to acsend an ever decreasing driving pressure also implies an ever decreasing oxygen level, giving less oxygen into the capillaries of our lungs and subsequently less oxygen in our blood and tissues.
Up to an altitude of around 8,000 feet the driving pressures should be high enough to provide sufficient oxygen levels. When entering terrain of 8,000 feet and higher pathophysiological changes may start to manifest due to lack of oxygen.
AMS is the most common of the three altitude illness conditions and is normally the predecessor of the two other and more serious conditions. AMS consists of headache plus any one of the following symptoms in varying degrees:
AMS may set in within hours or days having been in altitudes above 8,000 ft. The onset of symptoms is usually gradual and when trekking it is therefore important to continuously be watching out for early warnings such as excessive tiredness or headaches.
High Altitude Cerebral Edema (HACE) is a more serious condition probably caused by shifts of fluids into the tissues of the brain which causes swelling within the confines of the skull. The result is a higher skull pressure that may lead to lethargy and eventually coma. The symptoms of HACE are an extension to those of AMS
Anybody believed to have symptoms of HACE should immediately descend with assistance from others. This situation is serious enough to justify helicopter evacuation as if HACE is progressing to much it may ultimately lead to death.
High Altitude Pulmonary Edema (HAPE) is another serious condition which may either be following AMS or appear independently without any signs of AMS. As a result of low oxygen levels the pulmonary artery may narrow resulting in exudation of blood near the smaller branches of the lungs. A prolonged exudation may result in blood escaping into the aveoli leading to coughing with watery blood-tinged phlegm. Such exudation of the lung tissue may interfere with the oxygenation causing shortness of breath even at rest. The symptoms of HAPE are:
The best way to prevent altitude sickness is to ascend gradually. When above 3,000 m it is not recommended to ascend more than 300-400 m per day. Even if you’ve not ascended more than 300 m but still feel a headache, tiredness or any other of the above listed altitude sickness symptoms, always take a rest day to further acclimatize. Moreover, keep on drinking enough water so as to stay hydrated. Proper hydration helps to prevent altitude sickness. Please therefore also always stay away from alcohol when trekking. The general water drinking guideline is to drink 1 liter of water per 1,000 m. To exemplify, if at 4,000 m then 4 liter of water should be consumed per day, if at 5,000 m then 5 liter of water etc.
Another recommended way to prevent altitude sickness is the use of Diamox (Acetazolamide) pills so as to speed up the acclimatization. As soon as you ascend more than 3,000 m you can start taking 1 pill per day. Alternatively only take Diamox pills if starting to feel any of the altitude sickness symptoms.
We hope the above answers any questions you may have to Health and Safety. If not, please do provide us with feedback. We will then do our utmost to rectify any information you may feel is missing.