Lack of oxygen in the brain

Although it represents 2% of our body weight, The brain consumes approximately 20% of the oxygen we take in, varying the percentages depending on the brain area. For example, the sensory and motor areas spend more. This consumption is continuous, since it has very little capacity to store nutrients. Therefore, a lack of oxygen in the brain can have serious consequences.

The brain can last about 4 or 5 minutes without oxygen. Now, once that time has passed, cellular damage begins to occur, which will be greater the more time passes. In fact, If the lack of oxygen continues for more than 15 minutes, at least 95% of the brain tissue will be damaged.

Causes

Lack of oxygen in the brain It can be due to several reasons. Generally, it is caused by cardiocirculatory or respiratory failure. However, there are other reasons that can cause this injury and that constitute the classification of anoxia:

This anoxia is caused by breathing an insufficient amount of oxygen. For example, when you go to very high altitude places and the oxygen concentration is lower. Or due to drowning, severe asthma, choking, etc.

It takes place for a decrease or alteration in the ability of hemoglobin to oxygenate the blood.

Anoxia or ischemic hypoxia

In this case, the reduction in cerebral flow or blood pressure causes an inadequate supply of oxygen. This occurs for example in a stroke, brain hemorrhages or cardiac arrest. The latter are the most common cause of brain damage due to lack of oxygen.

Lack of oxygen in neonates

It is well known that perinatal hypoxia can have mild to severe consequences, with the leading cause of brain damage and neurological sequelae in children.

Approximately 5% occur in the time before childbirth, 85% during childbirth, and 10% in the neonatal period. The causes of the damage are usually compression of the umbilical cord, placental detachment or poor conduction of blood from the mother to the fetus, among others.

Lack of oxygen to the brain can also occur due to the consumption of substances that interfere with the use of oxygen. For example, due to poisoning from carbon monoxide, alcohol, acetone and even some anesthetics.

Consequences

As a last resort, The consequence of lack of oxygen is brain damage and even death. More specifically, the lack of oxygen first produces a loss of consciousness or a coma. After this period you could fall into a vegetative state.

If the person regains consciousness, then symptoms similar to those of a head injury occur. So, The severity of the damage and symptoms will depend on the anoxia and personal characteristics: duration, age of the person, whether they suffer from another associated disease, the duration of the coma and the extent, location and diffusion of the lesion.

Cognitive alterations

In relation to cognitive functions, The main symptom is short-term memory loss or learning capacity. This seems to be because the hippocampus, an area highly involved in learning new information, is highly sensitive to lack of oxygen. On the other hand, anoxia can affect executive functionscausing the person to be more impulsive, indecisive and have difficulties reasoning and processing information.

Also Visual alterations may occur, including cortical blindness.. That is, the image is received but cannot be processed on a conscious level, therefore the person cannot see. However, those who suffer from it act as if they see, but are unable to identify colors, shapes or objects.

Physical alterations

In addition, lack of oxygen can cause physical alterations, such as lack of coordination (ataxia), which is an obstacle to walking correctly. Or, apraxia, which is the inability to adequately perform the sequence of daily tasks, How to brush your teeth. Body stiffness, spasms or involuntary movements, as well as weakness in the extremities, may also occur.

Disorders

After an episode of anoxia or hypoxia, also epilepsy can develop or a similar condition consisting of epileptic seizures or muscle twitches.

Also, especially if the anoxia is in a neonate, cerebral palsy can occur. On the other hand, it is common to find disorders at the level of consciousness, where prolonged states of low response to the environment occur.

Can it be prevented?

Although there is a margin where people cannot control whether an accident happens to us, Yes, certain measures can be taken that can help us prevent anoxia or hypoxia, both to us and to people around us.

In the case of children, it is important make sure they are not exposed to suffocation risks, such as chewing food carefully or using small-piece games. It is also important to learn to swim and not leave children alone in pools, bathtubs or the sea.

In relation to the above, you can learn cardiopulmonary resuscitation techniques, as well as the Heimlich maneuver to avoid choking. Likewise, carbon monoxide levels can be controlled at home and avoid the use of drugs or non-prescribed medications.

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