With millions of sports enthusiasts going to high altitudes yearly, it is inevitable that the practicing emergency physician will eventually be required to consult or to treat the patient with altitude illness. The two case vignettes at the beginning of this article introduced the spectrum of altitude illness. In the first case, the "hangover" symptoms and time course were typical for AMS. The presentation was mild and management did not necessitate descent, though descent is always a consideration. Acetazolamide could be used to speed the acclimatization process. The second vignette represented a life threatening case of HAPE. The time course, occurring the second night at a new altitude, was classic. The symptoms of tachycardia, cyanosis, and bloody sputum classified the patient as having severe HAPE (Table 5
: Grade IV) and was at a significant risk for mortality. Descent was mandatory and the evacuation needed to involve minimal exertion and cold exposure for the patient. He required supplemental oxygen as his primary therapy, which unfortunately was not available nor was hyperbaric therapy. Some benefit pending descent could have been provided with pulmonary vasodilation therapy, e.g., nifedipine, salmeterol or albuterol, and dexamethasone.
All altitude illness can be prevented by ascending slowly: less than 300 m a day after 2500 m. If this is not possible and altitude illness occurs, then the definitive treatment is descent and oxygen. Pharmacologic therapy plays its most prominent role in the prophylaxis against altitude illness when slow ascent is not possible. Acetazolamide and dexamethsone are the preferred drugs for AMS prophylaxis. Nifedipine is the present recommendation for HAPE susceptible individuals who will be ascending rapidly. Ongoing research and development is centered on improved pharmacologic therapy, including the use of hosphodieterase inhibitors, sildenafil, and the longer acting agents, such as tadalafil, to prevent HAPE in susceptible individuals as well as for treatment.