The brain requires a constant flow of oxygen to function normally. In fact, the brain consumes about a fifth of the body’s total oxygen supply. When this flow is disrupted, brain cells begin to die, and one of two conditions results: i) hypoxic brain injury (due to a partial lack of oxygen supply to the brain); or ii) anoxic brain injury (due to a complete lack of oxygen supply to the brain). The two conditions are sufficiently related that the medical community uses the acronym HAI, which stands for hypoxic-anoxic brain injury.

Causes of HAI

The disease processes and injuries that can cause HAI vary widely, and include:
• stroke
• cardiac arrhythmia
• cardiac arrest
• suicide attempt
• near-drowning
• near-suffocation
• electrocution
• severe bronchial asthma attack
• carbon monoxide poisoning; and
• barbiturate poisoning.

Symptoms of HAI

Assuming one recovers from the initial loss of consciousness or coma, he or she may exhibit any of a number of symptoms. These cognitive symptoms may include:
• short-term memory loss
• a decline in executive functions (judgement, reasoning, information synthesis, attention, concentration)
• confusion
• depression
• hallucinations
• delusions
• personality changes; and
• language difficulties.


Chances for recovery from HAI are dependent upon length of unconsciousness, extent and location of brain damage, age of the victim, and initial recovery in the first month post-injury.

Jennifer Hartman, guest blogger