What is a Traumatic Brain Injury?

A traumatic brain injury (TBI) is caused initially by a blow to the head. TBI also includes potential complications seen after the initial injury caused by lack of oxygen to the brain tissues or increased pressure within the skull.

A TBI can, therefore, be analysed as three ‘injuries’:

First injury:

• This is the initial injury occurring in the seconds after the accident.
• Damage is described as closed, open or crush injuries.

• This occurs when the oxygen supply to the brain is reduced in the minutes and hours after the accident, worsening the damage already caused by the first injury.
• This can be caused by an obstruction to an airway or serious blood loss.

• This occurs as a result of blood leaking from damaged blood vessels, over a period of days or weeks, into the area causing the brain to swell.
• The skull is a fixed space and the brain can suffer damage if it squeezes against it.
• If the brain swells it can squeeze the blood vessels, limiting the brain's blood circulation.