People exposed to high altitudes often experience somatic symptoms triggered by hypoxia, such as breathlessness, palpitations, dizziness, headache, and insomnia. Most of the symptoms are identical to those reported in panic attacks or severe anxiety. Potential causal links between adaptation to altitude and anxiety are apparent in all three leading models of panic, namely, hyperventilation (hyp...

Exposure to high altitude imposes significant strain on cardiopulmonary system and the brain. As a consequence, sojourners to high altitude frequently experience sleep disturbances, often reporting restless and sleepless nights. At altitudes above 3,000 meters (9,800 ft) almost all healthy subjects develop periodic breathing especially during NREM sleep. Sleep architecture gradually improves wi...

Some birds perform flapping flight at remarkably high altitudes. A commercial aircraft flying at 6400 m. (21,000 ft.) was struck by an object, evidently a mallard duck from the feathers recovered later from a dent in the aircraft (Manville, 1963). Radar echoes attributed to passeriform and charadriform birds have been regularly detected at altitudes of 6100 m. (20,000 ft.) or more during night ...

Chronic mountain sickness (CMS) represents a variably reversible asynchronous syndrome of secondary polycythemia along with erythrocytosis, erythrocyte aggregation, hemoglobinemia, hemoconcentration, thrombocytopenia, increased whole blood viscosity, fibrinogenemia, prothrombotic state, pulmonary and systemic hypertension, and congestive heart failure, occurring due to hypobaric hypoxia-anoxia-...

More than 140 million people dwell at altitudes of over 2500 m. The Andes region is home to the greatest population density at an altitude of more than 3500 m. Equally, the number of persons living at sea level (SL) is growing, and they travel to medium, high, or extreme altitudes for occupational or scientific reasons, or to enjoy tourism or recreational activities, as is the case of hikers, m...

More than 140 million people dwell at altitudes of over 2500 m. The Andes region is home to the greatest population density at an altitude of more than 3500 m. Equally, the number of persons living at sea level (SL) is growing, and they travel to medium, high, or extreme altitudes for occupational or scientific reasons, or to enjoy tourism or recreational activities, as is the case of hikers, m...

The focus of the present study was to investigate the chemical composition of essential oil of Salvia hydrangea DC. ex Benth. growing wild in Kiasar-Hezarjrib, Iran. In addition, effects of altitude and some soil properties on the essential oil quality and quantity of S. hydrangea was identified. The samples collected from two altitudes (1100 and 2000 m) in blossoming period, were analyzed by h...

Acute mountain sickness (AMS) is a common problem while ascending at high altitude. AMS may progress rapidly to fatal results if the acclimatization process fails or symptoms are neglected and the ascent continues. Extensively reduced arterial oxygen saturation at rest (R-Spo₂) has been proposed as an indicator of inadequate acclimatization and impending AMS. We hypothesized that climbers less ...