What is brain swelling?
Brain swelling or edema is one of the types of ‘what we call secondary, mechanisms of brain damage, which commonly occur following an acquired brain injury. While the primary mechanisms of damage occur immediately at the moment of the injury, secondary mechanisms of damage tend to occur later and may be due to bleeding from damaged blood vessels (hemorrhage), and/or increased pressure within the brain (intracranial pressure) as the brain swells with fluid (edema or hydrocephalus) or blood. Secondary damage occurs more commonly after a severe brain injury. The further damage to the brain can be quite significant due to hypoxia (tissue death due to loss of oxygen) or herniation (squeezing out of brain tissue through small openings), and surgery may be necessary to stop the bleeding, remove clots, relieve pressure and/or swelling.
WHAT IS BRAIN DEATH?
Brain death is an irreversible type of unconsciousness distinguished by a total loss of brain functioning while the heart continues beating. While the legal definition for brain death differs between states, the typical clinical guidelines include the absence of reflex activity, movements, and respiration, dilated and fixed pupils, and electrical activity of the brain absent on two electroencephalograms (EEG) performed 12 to 24 hours apart.