altitude sickness

Also found in: Dictionary, Thesaurus, Medical, Legal, Wikipedia.

altitude sickness:

see decompression sicknessdecompression sickness,
physiological disorder caused by a rapid decrease in atmospheric pressure, resulting in the release of nitrogen bubbles into the body tissues. It is also known as caisson disease, altitude sickness, and the bends.
..... Click the link for more information.

Altitude Sickness


a pathological condition that arises upon ascent to great heights (above 3,000 m) resulting from lowered partial pressure of oxygen in inhaled air. The development of altitude sickness is associated with a disturbance of the function of certain organs and systems, chiefly of the cells of the higher sections of the central nervous system, resulting from oxygen starvation, or hypoxia. At heights under 3,000 m, a healthy person’s oxygen deficiency is compensated for by an increase in pulmonary ventilation (faster and deeper breathing), in blood circulation, and in hemoglobin and erythrocyte count in the blood. Further ascent brings on hypoxia, since the functions of the organism can no longer provide sufficient compensation. A shortage of oxygen in the surrounding air leads to lowered partial pressure of oxygen in the lungs and to lowered oxygen saturation of arterial blood. The major symptoms of altitude sickness include shortness of breath, heart palpitations, dizziness, noise in the ears, headache, nausea, weakness of the muscles, perspiration, blurred vision, sleepiness, and decreased stamina. The symptoms develop in phases, depending on the speed of ascent and on the functional state of the organism. Alcohol, fatigue, and insomnia lower the tolerance for great heights.

Treatments for altitude sickness include descent to a lower altitude, rest, cardiac medicines, and strong tea or coffee. In severe cases, inhalation of oxygen is called for. Inhalation of oxygen from a special apparatus while ascending to great heights prevents altitude sickness. Sports that increase the organism’s demand for oxygen and thus cause hypoxia develop the organism’s resistance to hypoxia. One variant of altitude sickness is mountain sickness. Along with an oxygen deficiency, other factors in mountain sickness are physical exhaustion, cold, and ultraviolet radiation. With acclimatization to the mountain climate, the symptoms of mountain sickness weaken. Relative stabilization of the physiological indexes begins after approximately a three-week stay in the mountains.


altitude sickness

[′al·tə‚tüd ‚sik·nəs]
In general, any sickness brought on by exposure to reduced oxygen tension and barometric pressure.

altitude sickness

In general, any sickness brought on by exposure to reduced partial pressure of oxygen and barometric pressure.
References in periodicals archive ?
He added: "I'm not sure how the altitude sickness will affect me - it hits some people worse than others.
Altitude sickness can be a problem, and I am a little concerned because there's nothing I can do to prepare for it, apart from taking the cocoa leaf.
The psychological aspects of the challenge were a constant internal saboteur, but the cause alone kept us going during the crippling altitude sickness and physical exertion.
I've been warned about altitude sickness and the sub-zero temperatures, but, to be honest, using a portable toilet worries me more
I got sick the most out of all seven of us in the group; I was OK until we reached the camp on the first day then altitude sickness hit me with the worst nausea, fatigue and vomiting.
Brian is hoping it won''t come to that and to boost the odds he plans to take altitude sickness tablets from the moment he lands at Nepal's Lucla Airport, renamed Tenzing-Hillary Airport in honour of St Edmund Hillary and Sherpa Tenzing Norgay, the first to reach the summit of Mount Everest.
Edinburgh scientists, who camped for three weeks at the height of 4730m to test altitude sickness in more than 200 climbers, warned that Africa's tallest peak can be fatal.
While most of the team reached the 5,895m summit, a small number were told to turn back as they were suffering from the dangerous effects of altitude sickness.
He added: "When we reached the peak all I wanted to do was sit down which is apparently the worst thing you can do when you are suffering from altitude sickness so everyone held me up before the climb back to base camp.
Anne, from Ashbrooke, Sunderland, used the expedition as an opportunity to test herself and has kept in touch throughout the expedition via emails, texts and Facebook, revealing how she has suffered from bouts of altitude sickness but battled on, sometimes walking 14 hours a day.
A HEARTBROKEN couple today paid tribute to their outgoing and caring daughter, who died of altitude sickness while on holiday.
Pete, being a pessimist - he'd say realist - by nature, does confess to feeling anxious about altitude sickness.