Anoxic brain injury is a type of brain damage brought about by the absence of oxygen distributed to the brain. It is a condition wherein there is no or little oxygen introduced into the tissues of the brain even if blood flow is sufficient. This condition is usually caused by an interruption of the respiratory. These interruptions in breathing may result from various situations such as drowning, choking, applying undue pressure to the chest and the abdomen, asthma and strangulation.

Lack of oxygen supply to the brain even for only a few minutes can lead to serious damage of the brain tissues. Such damage can affect those areas in the brain that are responsible for conscious behavior and speech. It also is very dangerous when the brain suffers from a severely deficient supply of oxygen, because aside from brain damage, unconsciousness or even death can happen.

Obstructions in the lung passages are not only the causes of anoxic brain damage. When people enter environments that are lacking oxygen and have excess levels of carbon dioxide or carbon monoxide, anoxia can result. For example, being stranded for hours in an elevator full of people can cause difficulty in breathing. Other factors that affect respiration are drug overdose, contact with a pulmonary agent or cyanogenic compound and seizures that could stop a person's breathing, including heart attacks and strokes. Problems during pregnancy and labor can also affect oxygen circulation, causing a baby to suffer from brain damage. Still births are also a big possibility.

Anoxic brain injury can be remedied at once in some cases. For instance, in cases of drowning and severe asthma attacks, applying artificial respiration and giving the patient sufficient breathing space can prevent brain injury. When proper action is not done at once, the patient could lose consciousness or even die.