While 8000 feet (2500 meters) is considered the usual threshold altitude for HAI, some persons are more sensitive to lower oxygen levels and may become ill at altitudes of 5000 to 7000 feet (1500 to 2100 meters). It is usually possible to prevent HAI by ascending slowly and allowing your body to adjust as you go.
The amount of oxygen in the air goes down as you climb higher above sea level and becomes very low at altitudes above 8,000 feet. If you travel to a high altitude, you may feel ill because the air has less oxygen in it.
It refers to altitudes above a certain point where the amount of oxygen is insufficient to sustain human life for an extended time span. This point is generally tagged as 8,000 m (26,000 ft, less than 356 millibars of atmospheric pressure).
Atmospheric pressure and inspired oxygen pressure fall roughly linearly with altitude to be 50% of the sea level value at 5500 m and only 30% of the sea level value at 8900 m (the height of the summit of Everest).
Symptoms of moderate altitude sickness are more intense and worsen instead of improve over time: Worsening fatigue, weakness and shortness of breath. Coordination problems and difficulty walking. Severe headache, nausea and vomiting.
At elevations more than 5280 feet above sea level people may start to feel the effects of altitude. This varies for every individual so some people may not feel effects until they reach elevations greater than 8000 feet.
The simple answer is yes. The lower the altitude, the richer the mix of oxygen in the air. A move from a high altitude to a significantly lower altitude will very likely lessen your need for an oxygen tank to deal with COPD.
Results of a four-year study by researchers at the University of Colorado suggest that living at altitudes around 5,000 feet (Denver is 5,280 feet above see level) or higher might increase lifespan.
The only way to accomplish this is by breathing oxygen through medical devices (masks, Gamow bags, and tents) or homes with oxygen-controlled rooms like in some mountain homes in Colorado and other mountainous regions. Portable hyperbaric chambers are also used at high altitudes, especially during emergencies [2].
The initial euphoria is a result of increased dopamine, the neurotransmitter contributing to feelings of pleasure, when entering high altitude. Dopamine is a short-burning fire, and then it's gone, Goodwin explained.
Above about 8,000 meters (26,000 feet), the human body cannot survive at all, and starts to shut down. Mountaineers call this altitude the "death zone." To prevent severe altitude sickness, mountaineers bring supplemental (extra) supplies of oxygen and limit their time in the "death zone."
At intermediate altitude (1,500 to 2,500 metres above sea level) altitude illness is unlikely, though possible. Acute altitude sickness arises after at least four hours spent at an altitude above 2,000 m. Ascending to heights greater than 2,500 m can trigger a range of symptoms including headache and vomiting.
The depth (distance from top to bottom) of the atmosphere is greatest at sea level and decreases at higher altitudes. With greater depth of the atmosphere, more air is pressing down from above. Therefore, air pressure is greatest at sea level and falls with increasing altitude.
[Conclusion] University students living at high altitude had a slower HR and higher oxygen saturation levels as well as higher lung and inspiratory capacity levels. Thus, physiological improvement in oxygen saturation levels and pulmonary function were seen in the individuals living at high altitude.
At high altitudes, the outside air pressure is lower than it is inside the lungs, making it more difficult to pull in the thinner air and for veins to pump oxygen throughout the body. That is why, breathing is difficult in mountain regions.
Altitude illness is divided into 3 syndromes: acute mountain sickness (AMS), high-altitude cerebral edema (HACE), and high-altitude pulmonary edema (HAPE).
The medication acetazolamide can reduce symptoms of altitude sickness and help improve labored breathing. You may also be given the steroid dexamethasone. Other treatments include a lung inhaler, high blood pressure medication (nifedipine), and a phosphodiesterase inhibitor medication.
The cabin air pressure in an airplane is adjusted to compensate for these high altitudes. The oxygen level is comparable to levels found in elevations of 5,000 to 9,000 feet. Both men and women can get altitude sickness. Age, general health, and physical condition do not affect your chances for altitude sickness.
Altitude exposure is known to cause an increase in adrenergic activity, blood pressure (BP) and heart rate (HR) in resting conditions. Much less is known on the effects of the hypoxic environment on the BP and HR response to physical exercise.
In altitude a greater amount of nitric oxide and ROS are produced that accelerate aging. High altitude hypoxia increases death rate and decreases life-expectancy.
An altitude of 500 feet above the surface, except over open water or sparsely populated areas.
Interactions between genetic, behavioral and environmental conditions at altitude are complex and may differently impact on mortality from various diseases. Living at higher altitudes seems to be associated with lower mortality from cardiovascular diseases, stroke and certain types of cancer.
Mountain air contains fewer toxins such as fine particles and allergens. Another advantage is that thin air can pass smoothly through the narrow, inflamed pathways in the lungs. If, however, the lungs are severely damaged and unable to expand, people should stay at lower altitudes.
Living at high altitude reduces risk of dying from heart disease: Low oxygen may spur genes to create blood vessels. Summary: Researchers have found that people living at higher altitudes have a lower chance of dying from heart disease and live longer.
"High-altitude living decreases the risk of heart disease: A major risk factor for development of heart disease, stroke and diabetes is lower in people that live at higher altitudes; this also applies to people with a family history of these diseases." ScienceDaily.