Altitude acclimatization

As far as the human body is concerned, the most significant characteristic of high altitudes is lower air pressure. Although the oxygen content remains the same throughout the atmosphere, the air pressure drops at higher altitudes. For example, the air pressure at the Mount Everest base camp is only half as high as at sea level. As the air pressure is the determining factor for the oxygen saturation in the blood, a drop in air pressure leads to a reduction of available oxygen for the body. Of course the body adapts itself to the reduced air pressure. The respiratory and pulse rates increase. However one effect of an elevated respiratory rate is the exhalation of greater quantities of carbon dioxide. This is not only beneficial to the body because its acid-base balance is altered: the blood becomes alkaline. The kidneys can equalize this effect, but they need a couple of days to do it. Meanwhile the blood becomes alkaline - this causes a drop in the body's ability to breathe faster and thus adapt quickly to the altitude. Further aspects of altitude acclimatization affect an increase in the red corpuscles (and with it the ability to transport oxygen) and an increase in the ability of the tissue to extract oxygen from the blood..

"Climb high, sleep low"

One very significant aspect of the adaptation to high altitudes is the speed of the climb. It is far more important than the actually reached altitude. This is why inexperienced trekkers are more greatly endangered than mountain climbers, who climb to far higher altitudes: the latter are, as a rule, better informed and plan their climb slowly and carefully. Those individuals who drive or fly to high altitudes are especially imperiled. First and foremost, flights to the Himalayas harbor additional risks, which must always be borne in mind. Rest days while climbing are just as important as they are after landing at a high altitude. During these rest days, you can climb as high as you want, as long as you return to where you slept the previous night ("Climb high, sleep low"). Persons who have suffered from a previous episode of mountain sickness are especially endangered. They must climb very slowly. Of course it it is always a good thing to be physically fit for a vacation in the mountains. But that still won't protect you from mountain sickness. Those people who are in the best physical condition also come down the most rapidly with mountain sickness for a very obvious reason: they climb too fast..

Important: get plenty to drink!

One very important factor is adequate liquid intake. You should drink from four to six liters a day (well above your thirst level), to combat the "thickening" of the blood and relieve the symptoms of mountain sickness..

Medication for mountain sickness

People frequently ask about medication for mountain sickness. Two drugs have been intensively studied: acetosolamide and dexamethasone. It has been shown that both of them can prevent the outbreak of light symptoms, but they will not, however, alter the course of a severe mountain sickness. This will primarily remove the body's warning signs, which should keep the traveler from climbing on to dangerous altitudes. Beyond this, taking acetosolamide can bring on unpleasant side effects, especially nausea, exhaustion and sleeplessness. This is why these medications are not recommended.

Mountain sickness begins with relatively harmless complaints, which nevertheless represent an important warning sign of more dangerous things to come. Loss of appetite, headache, sleeplessness, strange dreams, nausea, vomiting and a tightness in the chest. As the disease progresses further it brings about a collection of fluid in the lung (pulmonary edema). Patients complain of loss of breath, coughing and a whitish expectoration. Blue lips often become apparent. Should a brain edema, a collection of fluid in the brain, come about, patients develop the most severe headaches, giddiness, dizziness and occasionally hallucinations. Finally a limitation of consciousness occurs, followed by a coma, which often comes about overnight. The treatment of mountain sickness is simple and effective: get out of the altitude! Administration of oxygen can help, but the most important factor, however, remains the rapid descent, or transport to an altitude of at least 1,000 meters.