Acute Mountain Sickness is a clinical syndrome observed in unacclimatized persons usually within a few hours after rapid exposure to high altitude. Individual tolerance varies widely. Some experience symptoms at altitudes as low as 7000 to 8000 feet, although others tolerate altitudes of 14,000 feet with minimal symptoms.
There appears to be no way to predict unusual susceptibility, but rapid ascent, physical exertion, and poor physical condition increase the likelihood. Initial symptoms a:e usually mild to incapacitating headache, exertional dyspnea, malaise, and weakness. Insomnia, anorexia, nausea, vomiting, diarrhea, and abdominal pain may occur. Mental capacity and judgment may be impaired. Inability to sleep is a common problem.
Facts You Must Know About Acute Mountain Sickness
Cyanosis of the lips and nail beds, Cheyne- Stokes breathing and tachycardia are usually present. These manifestations usually subside gradually over a period of several days, but may recur at higher altitudes. In some instances the symptoms are severe and unrelieved except by oxygen or descent to a lower altitude. Gradual ascent with periodic halts of several days to allow acclimatization will prevent or reduce the severity of symptoms.
Acetazolamide, given in dosages of 250 mg. every eight hours prior to and during exposure to altitude, has been reported to reduce the frequency and severity of symptoms. The mechanism of its effect is not clear, but increased ventilation and alveolar oxygen tension, decreased carbon dioxide tension and serum bicarbonate, and absence’ of alkalosis were observed in treated subjects.
