Report by Sue Corkill, HW Tolerance

This month we continue with two of the more dramatic consequences of severe head injuries: coma and brain death.

Coma

Traditionally, coma has been defined as a sleep like state from which an individual cannot be aroused. This definition has been largely replaced by the more accurate definition of a state of unresponsiveness from which an individual has yet to be aroused. When a person is in a coma, their brain is operating at the lowest functional level. Most individuals in a coma have no awareness of their surroundings and are unable to respond to their environment. However, anecdotal stories have told of individuals who have awakened from a coma and have recollection of events that occurred while they were 'unresponsive".

A coma usually occurs as the result of a traumatic brain injury. The condition of being in a coma may last from several hours to days to months and even years. When a coma lasts for more than a month, the individual usually reaches a state where his or her eyes are open, but are vacant, with no purposeful responses. When individuals reach this state, they are usually referred to as being in a 'persistent vegetative state'-and no, that doesn't mean they're a vegetable. It means that only the 'vegetative' or automatic functions of the bodily systems are maintained, but there is no awareness.

The Glasgow Coma Scale (GCS) is often used to objectively evaluate an individual's neurological function. Using the assessment of eye opening, best motor (movement) response and best verbal response, a score is calculated from three (the worst) to eighteen (the best). A score less than eight indicates a state of coma. For more information on the Glasgow Coma Scale see: http://www.neuroskills.com/index.html?main=tbi/glasgow.shtml

So, what does this mean for our hero who is in a coma? If the individual-who is in a coma-survives the first seven to ten days from the initial brain injury, then long-term survival is favorable. The quality of that survival is questionable, however. Vigorous medical treatment following the initial injury; combined with aggressive multi-sensory stimulation and intense physical therapy/activity, usually means a better prognosis. Early treatment is designed to reduce intracranial pressure and treat other injuries (if present). Long-term care involves intense commitment to maintaining an environment that provides sensory stimulation and deflects the consequences of immobility; and then rehabilitation once the individual 'awakens'.

For more information regarding therapy during coma, please see: http://www.comarecovery.org/comatreatable.shtm

Brain Death

Brain death is the irreversible cessation of all brain activity. The brain is dead and cannot be resuscitated. An individual is considered brain dead when the following criteria is met:

The person cannot breath on his or her own (must be on a ventilator/respirator).
The pupils are fixed and dilated-they do not respond to light.
There is no response to painful stimuli.
There is no muscle tone or reflex activity in the arms and legs.
There is no brain stem activity: i.e. eyeballs are fixed, no corneal reflex, no response to caloric testing (putting ice cold water in the ear so it stimulates the ear drum causing the eyes to move) and no gag or cough reflex.

Once all these criteria are met, the person cannot be diagnosed as 'brain dead' until they've been off all medications that affect the central nervous system (i.e. opiate pain killers, like morphine and barbiturates, like Phenobarbital) for at least twenty four hours. And then he or she must undergo one of the following diagnostic studies:

A cerebral arteriogram, where dye in injected into the arteries of the brain and shows no blood flow in the brain.
A cerebral blood flow scan, which again shows no evidence of blood circulation in the brain.
Or a series of two EEG's (electroencephalogram) at about twenty-four hour intervals that show no electrical activity in the brain.

Once the diagnosis is made-using the above criteria-a person is considered brain dead. A dead brain has never been known to recover. Hearts, lungs and kidneys may continue to function-with the help of artificial means-for several days to as long as two or three weeks. If your character is brain dead, it will take some kind of divine (or alien) intervention to resuscitate him or her. Depending on the age and circumstances surrounding the original injury, (in the U.S. anyway) it is common practice to approach the family of the individual regarding organ donation.