The Effects Of Hypoxia & Anoxia To The Brain


Our bodies need a constant flow of oxygen in order to stay alive. Oxygen may enter the lungs through our mouths and noses but from here it is pumped directly to the brain, this is where the important work happens. If the brain does not get a continuous supply of oxygen every few seconds then it can soon become oxygen deprived. In this state, the brain can start to deteriorate rapidly and devastating and irreversible brain damage can soon set in.

What’s the Difference between Hypoxia & Anoxia?

Anoxic brain injuries are caused when there is a complete severance of oxygen to the brain over enough time to cause massive damage. Hypoxic brain injuries are caused when there is a partial lack of oxygen, an interruption in the oxygen flow that isn’t as complete as anoxic injuries but still enough to prevent the brain from operating at full capacity. The two terms are similar in meaning but there are changes between the two. Each represents a brain injury caused by lack of oxygen but hypoxic injuries can be more severe if the flow is not re-established soon. Generally, the term cerebral anoxia is used to describe both unless a distinction between the two terms becomes necessary, such as in extreme cases.

Common Causes of a Lack of Oxygen to the Brain

There are many different causes of an anoxic/hypoxic brain injury; here are some of the most common:

  • Choking on food or drink
  • Suffocation (this includes strangulation)
  • A severe allergic reaction causing swelling of the glands or neck
  • Severe asthma complications or asthma attack
  • Drowning or near drowning
  • Exposure to high altitudes with low oxygen
  • Carbon monoxide poisoning
  • Drug overdoes/excessive alcohol abuse can also cause this
  • Vomiting while unconscious
  • Severe electric shocks
  • Cardiac arrests, heart murmurs
  • Respiratory difficulties
  • Smoke inhalation
  • Irregular heart rhythms
  • Low blood pressure
  • Shock or severe panic attacks
  • Traumatic injury to the neck or chest

All of the above represent risks to breathing and the oxygen supply to the brain. Each of these over an extended amount of time can become incredibly dangerous. A hypoxic or anoxic brain injury, if severe, can lead to death or place the sufferer in a situation that leads to a vegetative state. Even those who survive a hypoxic or anoxic brain injury can suffer lifelong effects.

Acquired Brain Injuries

Like any acquired brain injury the symptoms can be unpredictable and depend on the person and the situation. Where the injury may not count as a traumatic brain injury, as in one that was caused by some kind of physical bump to the head, the symptoms and damage to the brain can be the same. As the symptoms cannot be directly seen, unlike a traumatic head injury, many people underestimate the effects and do not understand that the brain damage caused can be just as severe as any other brain injury.

Fortunately, brain damage from anoxia and hypoxia can heal over time. Brain injuries can heal if they are caught early and the right treatment is sought. Not everyone is in this situation however.