The symptoms of mild AMS are headache, dizziness, fatigue, shortness of breath, loss of appetite, nausea, disturbed sleep, and a general feeling of malaise (Princeton, 1995). These symptoms tend to increase at night when respiration is slowed during sleep. Mild AMS does not interfere with normal activity and symptoms generally subside spontaneously as the body acclimatizes to the higher elevation. Moderate AMS includes a severe headache that is not relieved by medication, nausea and vomiting, increasing weakness and fatigue, shortness of breath, and decreased coordination called ataxia (Princeton, 1995). Normal activity becomes difficult at this stage of AMS, although the person may still be able to walk on their own. A test for moderate AMS is to have the individual attempt to walk a straight line heel to toe. The person with ataxia will be unable to walk a straight line. If ataxia is indicated it is a clear sign that immediate descent is required. In the case of hiking or climbing it is important to get the affected individual to descend before the ataxia reaches the point where they can no longer walk on their own. Severe AMS presents all of the symptoms of mild and moderate AMS at an increased level of severity. In addition there is a marked shortness of breath at rest, the inability to walk, a decreasing mental clarity, and a potentially dangerous fluid buildup in the lungs. ACCLIMATIZATION There is really no cure for Acute Mountain Sickness other than acclimatization or descent to a lower altitude. Acclimatization is the process, over time, where the body adapts to the decrease in partial pressure of oxygen molecules at a higher altitude. The major cause of altitude illnesses is a rapid increase in elevation without an appropriate acclimatization period. The process of acclimatization generally takes 1-3 days at the new altitude. Acclimatization involves several changes in the structure and function of the bo...
