People suffering from hypoxia do not get enough oxygen to some or all of their body. There are several different types of hypoxia: hypoxic hypoxia, where the whole body is affected; hypemic hypoxia, where blood oxygen levels are low; ischemic hypoxia, where blood flow is restricted to certain parts of the body; and histotoxic hypoxia, where cells are unable to process the oxygen delivered to them. All of these situations can be very dangerous and life-threatening. Just as there are various types of hypoxia, there are also a variety of hypoxia causes.
One of the main hypoxic hypoxia causes is altitude sickness. People who travel to higher altitudes than they are used to may be affected by the decreased oxygen levels in the air they breathe. Symptoms of this type of hypoxia typically set in slowly and may include fatigue, headache and nausea, and shortness of breath. Sufferers should try to rest, drink plenty of fluid and slow or stop their ascent to higher altitudes if symptoms persist.
Numerous other situations can also be generalized hypoxia causes. Those who use nitrous oxide and other inhalants as recreational drugs are at risk of decreasing oxygen levels in their bodies. People with conditions that affect their breathing like sleep apnea, asthma or emphysema may be affected. Sometimes complications arise from the use of anesthesia, which can lead to oxygen deprivation in the body. Heart failure can also be a cause.
Ischemic hypoxia, which is also referred to as stagnant hypoxia, can affect many different parts of the body and damage tissues. Possibly one of the most dangerous is loss of oxygen to the brain, which can lead to severe, irreversible brain damage. Some hypoxia causes that affect the brain include choking, strangling or suffocation. Blocked arteries leading to the head may be to blame. Cerebral trauma and blood clots can also cut off blood supply to areas of the brain.
In cases of histotoxic hypoxia, cells are damaged and are therefore unable to absorb and use oxygen. This is often the result of overuse of drugs or alcohol. Intake of certain poisons, such as cyanide or hydrogen sulfide, can also be a cause.
Some people may experience decreased oxygen levels in the blood, called hypemic hypoxia. Deformities or deficiency of hemoglobin, which carry oxygen in the blood, may be to blame. This condition is also commonly caused by carbon monoxide poisoning.