Altitude sickness
Altitude sickness, also known as acute mountain sickness, is a condition caused by low oxygen levels (hypoxia) that occurs when individuals rapidly ascend to high altitudes. The primary symptoms include headache, decreased appetite, insomnia, fatigue, and nausea, and can develop at elevations above 1,980 meters (6,500 feet). There are four main types of altitude sickness: acute mountain sickness, high-altitude pulmonary edema (HAPE), high-altitude cerebral edema (HACE), and high-altitude retinopathy (HAR). While many experience mild symptoms, severe cases can lead to life-threatening conditions, particularly HAPE and HACE, which can result in significant mortality rates.
Prevention is crucial, with recommendations for slow ascents and avoidance of alcohol and certain medications during the first 48 hours at high altitudes. Most individuals adapt to altitude changes within a few days; however, in cases of severe symptoms, immediate descent to lower altitudes is necessary. Treatments may include corticosteroids and supplemental oxygen, while premedication with acetazolamide can help mitigate symptoms. It is advisable for those with chronic health conditions to consult a healthcare provider before engaging in high-altitude activities.
Altitude sickness
ANATOMY OR SYSTEM AFFECTED: Brain, ears, head, lungs, nervous system, respiratory system
DEFINITION: A condition resulting from altitude-related hypoxia (low oxygen levels).
CAUSES: Rapid ascent to high altitudes, hypoxia (low oxygen levels)
SYMPTOMS: Headache, decreased appetite, insomnia, fatigue, nausea, death in severe cases
DURATION: A few days
TREATMENTS: Descent to lower altitudes, corticosteroids, oxygen
Causes and Symptoms
There are four types of altitude sickness: acute mountain sickness, high-altitude pulmonary (HAPE), high-altitude cerebral edema (HACE), and high-altitude retinopathy (HAR). Though most patients have mild symptoms, death is not uncommon in severe cases. Illness is associated with rapid ascent to mountain areas by tourists, skiers, and mountaineers. Residents of mountainous regions are less susceptible because their bodies have adapted to lower oxygen levels. It is estimated that up to one-quarter of tourists skiing in the mountains of the western United States have experienced some manifestations, although mild ones, of altitude sickness.
Acute mountain sickness is characterized by headache, decreased appetite, insomnia, fatigue, nausea, and onset at altitudes above 1,980 meters (6,500 feet). The risk of becoming affected increases with young age, quick ascent, and a past history of acute mountain sickness. Symptoms usually last for a few days. Between 5 and 10 percent of patients with acute mountain sickness progress to HAPE, which occurs when the small blood vessels leak, allowing accumulation in the lungs. Mortality from HAPE ranges from 11 to 44 percent. The related condition HACE occurs when fluid accumulation in the causes increased pressure within the skull. Neurologic signs such as confusion and may be noted.
Treatment and Therapy
Prevention is crucial to the of and from altitude sickness. Ascents should be slow, especially those involving physical exertion. Sedatives and salt should be avoided; alcohol should be avoided for the first forty-eight hours. Most people adapt to altitude changes within three days. Returning to lower altitudes at night is advised. Premedication with acetazolamide, a prescription drug, will hasten and reduce symptoms. In serious cases, descent to lower altitudes is vital. Corticosteroids, oxygen, and hyperbaric treatments may be used. Chronically ill persons should check with their doctors before attempting strenuous activity at high altitudes.
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