Hypoxia is a family of conditions characterized by a lack of oxygen in the body's tissues. The condition may encompass the general body, or a specific area, such as the brain. In all cases, it can be dangerous or deadly, because without oxygen, the human body cannot function. Treatments for this condition usually start with providing concentrated oxygen to the patient for the purpose of stabilization, and then addressing the underlying cause of the hypoxia.
A number of problems between the moment air is inhaled and the time that oxygen is delivered to the cells can lead to hypoxia. For example, people at high altitude breathe “thin” air with reduced amounts of available oxygen, meaning that they inhale less oxygen than they need. Likewise, workers in a chemical lab might experience this condition as a result of an improperly controlled gas. Breathing problems such as asthma and constricted airways can cause a drop in oxygen levels in the blood, as can problems with the gas exchange in the lungs, or the hemoglobin cells which transport oxygen throughout the body.
When someone develops hypoxia, the condition is characterized by things like cyanosis, confusion, euphoria, nausea, dizziness, rapid breathing, or the sensation of air hunger. The condition can be diagnosed by drawing blood and determining the amount of dissolved oxygen present, or by looking for obvious signs of conditions which could cause oxygen deprivation, ranging from strokes which inhibit the supply of oxygen to the brain to collapsed lungs.
In some cases, the body is getting plenty of oxygen, but it can't use it, due to physiological problems. Some conditions which involve red blood cells cause hypoxia, by making it impossible for the cells to deliver needed oxygen, or by interfering with the process these cells use to bind and transport oxygen. In these instances, there may be no obvious cause for the patient's condition, which can sometimes make it challenging to diagnose.
Working and traveling at high altitude is a leading cause. This condition can also be caused by changes in cabin pressurization or interruptions to a plane's oxygen supply. Health conditions including cancers of the lungs, asthma, severe allergic reactions, strokes, and blood clots, among many others, can also contribute to the development of this condition. The condition may not always be readily evident to the patient, because oxygen deprivation can lead to subtle symptoms, which makes it important for people to be aware of personality and behavior changes in people who are at risk of developing hypoxia. A normally stoic person who suddenly becomes giddy, for example, might be suffering from oxygen deprivation.