DISORDERS CAUSED BY ALTITUDE - Medicine for Mountaineering and Other Wilderness Activities - page 353

lapse—and should be given only by medical professionals familiar with its effects. In the
past,furosemidewasusedtoremovefluidfromthelungs,butthisstrongdiureticcancause
a large urine output, resulting in a drop in blood volume and collapse. Persons who could
walk with a little help have required litter evacuation after furosemide administration.
Recovery from HAPE usually is surprisingly rapid. Individuals with HAPE may reas-
cend gradually after a few days spent recovering at a lower altitude.
Prevention of HAPE is the same as for AMS: gradual ascent with time for acclimatiza-
tion.Heavyphysicalexertionshouldbeavoidedforthefirstfewdaysafterarapidascentto
high altitude. Nifedipine starting one day before ascent, and then continued during ascent,
is recommended for prevention in individuals with a prior history of HAPE. Nifedipine is
thedrugwiththelongesthistoryofuseforpreventionofHAPE.Otherdrugsthathavebeen
shown in more recent studies to prevent HAPE include inhaled salmeterol (Serevent®), a
drug used for treating asthma; the corticosteroid drug dexamethasone; and tadalafil (Cial-
is®). All these drugs require a physician's prescription and could be used for prevention
of HAPE in susceptible persons, but consultation from a physician knowledgeable about
high-altitude illness should be obtained.
Individuals who have pulmonary vascular disorders such as primary pulmonary hyper-
tension or the congenital absence of one of the pulmonary arteries are very susceptible to
HAPE, and they develop this disorder at much lower altitudes. If such persons wish to go
to higher altitudes, they must consult their physician, obtain drugs such as nifedipine (al-
though this drug has not yet been tested in such individuals), and be prepared to descend
immediately.
Table 24-4 lists the common high-altitude illnesses.

Table 24-4 The Spectrum of Common Altitude Illness

ACUTE MOUNTAIN SICKNESS (AMS)
• Headache with any of these symptoms:
• Poor appetite, nausea, or vomiting
• Fatigue and/or weakness
• Dizziness/lightheadedness
• Difficulty sleeping
HIGH-ALTITUDE CEREBRAL EDEMA (HACE)
• Increasing headache
• Confusion
• Ataxia (trouble walking—tested by heel-to-toe walking)
• Progressing disorientation