Anoxic Brain Damage

Anoxic brain damage is injury to the brain due to a lack of oxygen. Hypoxia is the term to describe low oxygen. Brain cells without enough oxygen will begin to die after about four minutes.

  • Causes

    Oxygen is carried to the brain in the blood.
    Anoxic brain damage may occur if:


    • Blood flow to the brain is blocked or slowed. This can happen with:

      • Blood clot or stroke
      • Shock and heart problems, like heart attack

    • The blood flow is normal but the blood is not carrying enough oxygen. This may happen if:

      • You have lung disease
      • There is a lack of oxygen in the air, which may occur at high altitudes

      • You have prolonged exposure to certain poisons or other toxins, such as carbon monoxide
      • You have an event that is stopping you from breathing normally, such as drowning, choking, or suffocation

  • Definition

    Anoxic brain damage is injury to the brain due to a lack of oxygen. Hypoxia is the term to describe low oxygen. Brain cells without enough oxygen will begin to die after about four minutes.

    Progression of Anoxic Brain Damage
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    Copyright © Nucleus Medical Media, Inc.

  • Diagnosis

    The doctor will ask about your symptoms and medical history. A physical exam will be done. You may need to see a doctor who specializes in brain problems.

    These tests may be ordered to learn the extent of the brain damage and the part of the brain that is involved:

    • Head CT scan
    • MRI scan
    • Electroencephalogram
      (EEG)—a test that measures the electrical activity generated by the brain
    • SPECT scans—a type of CT scan that examines areas of the brain for blood flow and metabolism

    • Evoked potential tests—tests used to evaluate the
      visual, auditory, and sensory pathways

  • Prevention

    To your chance of having anoxic brain damage, take these steps:

    • Chew your food carefully
    • Learn to swim
    • Carefully supervise young children around water
    • Stay clear of high voltage electrical sources, including exposure to lightning
    • Avoid chemical toxins and illicit drugs
    • Install carbon monoxide detectors

  • Risk Factors

    The following accidents and health problems may increase your chance of anoxic brain damage:

    • Sudden
      cardiac arrest
      or heart attack
    • Choking
    • Suffocation
    • Drowning
    • Electrical shock
    • Malfunctioning gas appliances that produce carbon monoxide
    • Heart arrhythmia

    • Stroke
    • Drug use

  • Symptoms


    Severe damage may lead to a
    coma
    or a
    vegetative state. Mild to moderate hypoxic brain damage may cause:

    • Headache
    • Confusion
    • Decreased concentration and attention span
    • Mood swings and/or personality change
    • Intermittent loss of consciousness
    • Seizures
    • Poor coordination

    Rarely, there may be a decline in brain function a few days or weeks after the event occurred. This is caused by delayed injury in the brain.

  • Treatment