Your brain depends on oxygen. Even just a minute or so of oxygen deprivation can cause a cascade of reactions that damage your brain. Cerebral anoxia occurs when your brain is completely deprived of oxygen. When oxygen flow is reduced—usually due to reduced blood flow—but not completely eliminated, cerebral hypoxia is the result.
In some cases, your brain responds to the loss by temporarily increasing blood flow in an attempt to provide more oxygen. Though this can save your life if your brain is deprived of oxygen, it can also cause cardiovascular episodes such as brain bleeding, strokes, and ruptured blood vessels in the brain, particularly if you have other cardiovascular problems.
Cerebral hypoxia can cause both immediate and long-term brain damage, and the course of recovery from a serious episode of cerebral hypoxia is unpredictable. Only a doctor can properly assess you, so if you suspect your brain has been deprived of oxygen, seek immediate medical care.
Doctors classify hypoxia of the brain into four distinct categories, ranging from least to most severe:
Cerebral hypoxia is a medical emergency, and victims often know the cause, particularly if they've fallen or suffered another traumatic injury. When cerebral hypoxia is due to a stroke or other internal issue, symptoms can appear more slowly.
Some warning signs that your brain has been deprived of oxygen include:
The effects of cerebral hypoxia depend primarily on how long the brain is deprived of oxygen. Short-term diffuse hypoxia often produces no effects at all. For instance, a wrestler who loses consciousness with his opponent's arm around his neck will likely regain full functioning after he regains consciousness. People who experience this sort of short-term oxygen deprivation, though, will still experience symptoms. Those include:
When hypoxia lasts less than 60 seconds, it is unlikely to cause lasting damage. At two minutes, the risk of brain damage becomes more likely, while at three to four minutes, it becomes a near-inevitability. The long-term effects of cerebral hypoxia can include:
The most important treatment for cerebral hypoxia involves removing the source of the oxygen deprivation. Choking victims may need the Heimlich maneuver or to be intubated. Blood clots might need to be removed, or the patient might need the assistance of a ventilator until the source of the oxygen deprivation can be discovered.
Thereafter, there is no specific treatment for cerebral hypoxia. The brain remains a mysterious organ, and we do not yet know how to reverse brain damage or regenerate brain cells—though experimental research has shown some promising results. Instead, doctors focus on addressing the symptoms of cerebral hypoxia. This typically means extensive physical, occupational, or speech therapy to teach your brain how to work around any damaged areas. Such therapy can be challenging and emotionally draining, but the more committed you are to challenging your brain, the more likely it is that you will see improvements in functioning. Some other treatments include:
Researching information on your own can provide useful context when talking to your physician and other medical professionals but it is not a substitute for medical care. Be sure to speak to your doctor about any questions you have regarding an injury or treatment.
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