Dr. M.J. Bazos,
M.D Patient Handout
ALTITUDE
SICKNESS
About Your
Diagnosis
High altitudes are low oxygen environments. As
you go up, an adequate oxygen supply is maintained by various compensations such
as increases in breathing rate and heart rate. High altitude causes fluid shifts
that may lead to swelling of the hands, face, and feet. Rapid exposure to
altitudes of 7,000– 8,000 feet or more (for comparison, most Colorado ski
resorts are near 9,000 feet) may overwhelm your body’s ability to adapt,
potentially leading to such altitude illnesses as acute mountain sickness,
highaltitude pulmonary edema, and high-altitude cerebral
edema.
Living With Your
Diagnosis
Acute mountain sickness (AMS)
is characterized by headache, nausea, vomiting, shortness of breath, difficulty
sleeping, dizziness, and malaise, which typically occur 6–48 hours after
ascent. Symptoms may be mistaken for alcohol hangover, exhaustion, or infection.
Acute mountain sickness is the most common altituderelated illness; 25% of
individuals may be affected at 7,000 feet and as many as 50% at 15,000 feet. Men
and women are equally susceptible, yet younger adults may be more vulnerable.
Acute mountain sickness is also more common in individuals with underlying lung
problems, previous history of AMS, and those who usually live at sea level.
High-altitude pulmonary edema refers to the abnormal accumulation of fluid in
the lungs at altitudes higher than 8,000 feet. This is a life-threatening
condition that often strikes young, fit climbers who have made previous trips to
high altitudes without problems. Symptoms usually develop within 2–4 days
and begin with decreased exercise performance. Symptoms of AMS may also be
present. Later symptoms may include cough, chest congestion, shortness of breath
at rest, decreased level of alertness, and incoordination. High-altitude
cerebral edema is an illness caused by brain swelling. Severe headache, walking
problems, and mental dysfunction (hallucinations, reduced responsiveness, and
even coma) are the characteristic symptoms. This is a life-threatening condition
and frequently occurs together with high-altitude pulmonary
edema.
Treatment
Treatment
of altitude-related conditions depends on the severity of the illness and the
environment. Symptoms of AMS usually spontaneously resolve in as little as
1–3 days. Some minor symptoms, such as headache, can be treated with
acetaminophen or aspirin. More significant symptoms can be relieved with descent
or drugs such as acetazolamide, which stimulates breathing and helps prevent
fluid retention. For high-altitude pulmonary edema, rest and supplemental oxygen
are usually the initial treatments. For severe illness or when oxygen is not
available, descent is mandatory. Immediate descent and oxygen therapy are
recommended for high- altitude cerebral edema to help prevent serious neurologic
damage or death. Dexamethasone, a steroid, is often used to help prevent or
reduce brain swelling.
The
DOs
The most effective preventive
measure for altitude- related illness is a gradual ascent allowing for 2–4
days of acclimation at altitudes of 6,000–8,000 feet before ascending to
higher elevations. Discuss with your health care provider the need for drug
therapy to help prevent altitude-related illness. Acetazolamide is often used to
prevent altitude- related symptoms. It is usually started 1–2 days before
ascent and continued for 2 or more days at high altitude. The most common side
effects are nausea and numbness/tingling of the lips, fingers, and toes.
Acetazolamide preventive therapy is usually reserved for those known to be at
risk for AMS or for those who must reach altitude very
quickly.
The
DON’Ts
• Avoid alcohol and
sleeping pills at high altitude because they may worsen both sleep quality and
AMS symptoms.
• Avoid overexertion
when initially arriving at high altitude. Unfortunately, exercise before
traveling to high altitude does not help prevent altitude-related
illnesses.
• Avoid acetazolamide if
you are allergic to sulfa drugs.
•
Avoid reexposure to high altitude if you have had previous problems with
high-altitude pulmonary edema or high-altitude cerebral
edema.
When to Call Your
Doctor
Altitude-related illness may
occur in an area where contact with a doctor is not possible. The development of
neurologic or respiratory problems should be taken very seriously and should
initiate as safe and quick of a descent as possible.