Altitude hypoxia refers to a number of conditions caused by the lack of oxygen experienced when at a high altitude. It is commonly experienced by mountain climbers who ascend too quickly. The symptoms range from mild headache to more severe and life-threatening brain swelling and pulmonary edema, or swelling of the lungs. There are various medications available to prevent and treat the effects of altitude hypoxia.
The higher the altitude, the thinner the air, which means that less oxygen can be inhaled. The body is a complex system of organs and processes that are all connected. Oxygen is one of the most important players in many of these systems and is necessary for the normal functioning of the body. The balance of oxygen is a delicate one. In the case of altitude hypoxia, a decreased oxygen supply results, and this may cause a number of medical conditions.
Mountain sickness usually presents with headache, tiredness, dizziness, pallor, a lack of appetite and nausea. If these symptoms develop, it is vital to either descend or stay at that altitude until symptoms improve. Further ascent should not be attempted. Acetazolamide is sometimes used for treatment, and symptoms may be treated with anti-nausea tablets and analgesics.
If left untreated, mountain sickness may progress to other, more serious conditions such as high altitude pulmonary edema (HAPE) or high altitude cerebral edema (HACE). These are medical emergencies that if left untreated can result in death. Anybody going to high altitude areas should be aware of these conditions and know the symptoms and treatment.
HAPE, or swelling of the lungs, presents as shortness of breath and a decreased exercise performance. The lips may become pale and the nails may get a blue tinge with worsening respiratory symptoms, so the condition requires immediate treatment. Descent to a lower altitude and oxygen may reverse the effects, or medication such as nifedipine or dexamethasone may help, depending on the severity of the condition. HACE, or brain swelling, may also occur and presents with confusion and a lack of coordination. Without treatment, coma may result.
Some people are more susceptible to altitude hypoxia than others, and the exact reasons behind this are not entirely established. Factors that seem to increase the likelihood of a person developing altitude hypoxia include obesity, younger age and the female gender. Regardless of contributing factors, the best way to prevent altitude hypoxia is with a slow ascent, stopping every couple of thousand feet to rest and allow the body to readjust to the change in pressure. Prophylactic medication may also be taken.
