Also known as hypobaropathy, altitude sickness is an illness caused by being at a high altitude where air pressure is low, and there has been no gradual exposure or prior acclimatization. It often occurs at altitudes more than 8,000 feet with skiers and mountain climbers. More acute symptoms may occur at altitudes above 12,000 feet and can lead to high altitude cerebral edema (HACE) or high altitude pulmonary edema (HAPE). When not treated properly, acute altitude sickness can lead to life-threatening circumstances.
At sea level, the concentration of oxygen is about 20 percent. At higher altitudes, the atmospheric concentration of oxygen stays the same, but the amount of oxygen molecules breathed in is reduced. To compensate for the lesser amount of oxygen breathed in, one must breathe faster. At the same time, the heart muscle must beat faster. While faster breathing increases oxygen levels in the blood, sea level concentrations are not met. Symptoms of altitude sickness often include feeling exhausted, dizzy or nauseous. According to the National Health Service, about 25 percent of Colorado skiers and 34 percent of Swiss Alps skiers experience some degree of altitude sickness at heights over 12,000 feet. On average, approximately three-quarters of the population experiences mild altitude sickness at heights over 3,000 feet.
Complications and Treatment of Altitude Sickness
The two major complications of altitude sickness are HACE and HAPE. With HACE, insufficient oxygen causes fluid leakage through the capillaries and results in a swelling of the brain. Untreated, HACE can result in death. It is recommended that people should descend at least 2,000 feet immediately. Historically, it was believed that survivors of HACE had no trace of bleeding in the brain after experiencing HACE. However, researchers at the University Hospital in Heidelberg have conducted studies that demonstrated evidence of microhemorrhages in the brain years after the incident through magnetic resonance imaging. HAPE causes a fluid build-up in the lungs and prevents oxygen from entering the bloodstream. Often, the chest will tighten, and breathing becomes more difficult. Disorientation and confusion are likely to follow. Like HACE, those with HAPE should descend 2,000 feet immediately.
Descending to a lower altitude is often the best option for those with altitude sickness symptoms. People with moderate symptoms typically respond well as long as they remain at a lower altitude for at least 24 hours. This gives the body time to acclimatize. There are several methods for the treatment of altitude sickness. Physicians at mountain resorts usually administer pure oxygen when breathing problems persist. If quick descent is not possible, Gamow bags are used until rescue evacuation is possible. A Gamow bag is a plastic hyperbaric chamber with a foot pump for inflation. These devices are often effective to reduce altitude sickness at heights up to 5,000 feet.
As reported in the Annals of Emergency Medicine, researchers from the Stanford University School of Medicine have reported that ibuprofen is effective in treating moderate symptoms of altitude sickness. In addition, recent research by Dr. Jean-Paul Richalet published in the American Journal of Respiratory and Critical Care Medicine indicates that Viagra may help reduce health problems associated with altitude sickness. Dr. Jean-Paul Richalet conducted a study of 12 healthy men who were not accustomed to high altitudes. Participants were taken to a French mountain town 1,000 feet above sea level. After adjustment, the participants were taken on a helicopter ride 10,000 feet higher to the highest point in Western Europe. Half of the group was given Viagra, and the other half was given a placebo. Both groups had challenges in adjusting and experienced stomach issues and dizziness. After two days, the ones who had taken Viagra began to experience blood pressure normalization faster than the placebo group. The Viagra group had 6 percent lower blood pressure while the placebo group had 21 percent higher than normal blood pressure ratings.
Prevention of Altitude Sickness
The best way to prevent altitude sickness is by acclimatization. With gradual ascent, the body can adjust to the increasing altitude. When climbing high altitudes, it’s best to climb no more than 900 feet per day. Those with moderate symptoms of altitude sickness should stay at their current height and wait until the symptoms have gone away completely before ascending. Eating a high calorie diet and consuming 5 to 6 liters of water per day can serve as a positive adjunct to preventing altitude sickness.
Medications like acetazolamide and dexamethasone may also help to prevent altitude sickness. Acetazolamide accelerates one’s breathing rate and corrects the chemical blood imbalance caused by altitude sickness. It also helps reduce the symptoms of altitude sickness, such as headache and dizziness. Dexamethasone is a steroid hormone that acts as an immunosuppressant and anti-inflammatory agent. Specifically, it helps reduce swelling in the brain.