In such injuries you see bleeding into the brain, swelling and congestion of damaged tissue, and to a lesser degree invaision of infectious organizms.  Each of which cause brain tissue to die off, this is known as secondary damage.  In extreme cases the swelling is so extensive that portions of the brain are forcibly squeezed outside of the skull.  The dead and dying tissue is then surgicaly removed.  In other cases the skull is sawed off and placed in cold storage to better accommodate the swollen brain.  TBI Glossary

     There are two principle types of coma associated with head and spinal trauma.  The first type results from bruising, swelling, and tearing of delicate brain tissue. Often, they are accompanied by severe head injuries, and by fractures of the skull.  Respiration is labored due to pulmonary congestion, or chest wounds.  Hemiplegia, decorticate rigidity (arms flexed and adducted; legs and often trunk extended, or decerebrate rigidity (jaws clenched, neck retracted, all limbs extended) is common.  Lumbar puncture reveals bloody Cerebrospinal Fluid, CSF accompanied by elevated blood pressure (intracranial pressure), coupled with a slowing pulse and respiration.

     The second type of coma is caused by damage to the brainstem.  Signs include coma. laborious breathing, pinpoint pupils, quadrispasticity with arms flexed and trunk and legs extended, but without intracranial pressure (elevated blood pressure).  Such cases almost always imply severe brain damage and carry a poor prognosis. 

     Since severe head injuries are often accompanied by thoracic damage, pulmonary edema (some of which is undoubtedly neurogenic), hypoxia, and an unstable circulation often complicate the neurologic problems created by the injury.  Damage to the cervical spine also a common accompaniment, can cause fatal respiratory paralysis or permanent quadriplegia from spinal cord injury; other cord damage can be almost as disastrous. 

     Complications:  Acute subdural or intracerebral hematomas are common in severe head injury and, together with severe brain edema, are present in most fatal cases.  All three conditions cause signs of progressive rostral-caudal neurologic deterioration in the form of :  deepening coma, widening pulse, dilated pupils, spastic heimplegia with hyperreflexia, quadrispasticity, pupillary fixation to light, decorticate rigidity, decerebrate rigidity.    (See: TBI Glossary)

      Coma has two principle stages and many intermediary stages. During the first stage of coma patients are incapable of voluntary activities such as eye opening, and speech.  In some cases primitive avoidance responses, such as gag reflex, response to noxious stimuli, and responce to pain might be absent.   In the second stage of coma, they open their eyes, but they don't do anything. They don't follow commands. They don't speak. They don't interact with their loved ones, this is called a vegitative state. 

    About 5% to 10% of all coma patients are incapable of conscious behavior, and end up vegetative, which most of the public think of as prolonged coma. So, when the patient opens his or her eyes, he or she is no longer in coma, but s/he's not doing anything. So, s/he's just aroused, which means s/he's in a vegetative state.  Even today, with all of our impressive medical advances, there remain more questions than answers regarding coma. 

  Scientists used to think that all the damage to the brain occurred at the moment of impact. But now, they know that a lot of the damage actually occurs afterwards, in the first week in the hospital. The brain swells up, which compromises its ability to get enough blood and oxygen, and then, parts of the brain die. That damage in itself can be far worse than the first injury.

  At the moment of impact, the patient's brain is violently thrusted back and forth inside the skull, tearing blood vessels and pulling nerve fibers. These injuries cause the brain to swell, blocking the flow of oxygen-carrying blood. Such a condition could result in massive strokes and/or brain death. 

There's this period of time which can last from a few days to a week -- It can even last up to months -- where there's no conscious behavior. 

     The most common cause of death and disability in young people in the age of one to 44 is head injury.  In other words, every ten minutes head injury claims the life of yet another child.

The brain is one of the most complicated organs of the body, subject to much study and misunderstanding.

     Dr. Ghajar discovered an alarming number of discrepancies in coma management when he gathered leading neurosurgeons to develop a protocol called the Guidelines.  They spent two years meeting all over the country, reviewing 3,000 scientific research articles on head injury, and then came together with a document which provides guidelines for treatment and managment of patients with severe head injury. It  presents a  radical new approach to the treatment of severe brain injury, one which not all neurosurgeons agree is best for coma patients. Available through the Brain Trauma Foundation, the Guidelines for treating head trauma were approved by the World Health Organization on May 15, 1997.

    It can change the very nature of family life; the resultant emotional difficulties can affect the cohesiveness of the family unit.

     Typically, the emotional damage is intense, affecting family and friends for years afterward and sometimes leading to the breakup of previously stable family units. Family & Child Resources  

	The GCS is scored between 3 and 15, 3 being the worst, and 15 the best. It is composed of three parameters : Best Eye Response, Best Verbal Response, Best Motor Response, as given below :
	Eye Response: 1 No eye opening. 2 Eye opening to pain 3 Eye opening to verbal command 4 Eyes open spontaneously. Best eye response (4)
	Verbal Response: 1 No vocal response  2 Inconsolable, agitated 3 Inconsistently consolable, moaning 4 Cries but is consolable, inappropriate interactions 5 Smiles, oriented to sounds, follows objects, interacts Best verbal response (5)
	Motor Response: 1 No motor response 2 Extension to pain 3 Flexion to pain 4 Withdrawal from pain 5 Localizing pain Best Motor Response. (6) .
	Note that the phrase 'GCS of 11' is essentially meaningless, and it is important to break the figure down into its components, such as E3V3M5 = GCS 11.
	A Coma Score of 13 or higher correlates with a mild brain injury, 9 to 12 is a moderate injury and 8 or less a severe brain injury.