One of the prime benefits of the GCS is that it can be used by emergency medical technicians in the field as well as by doctors and other medical personnel in the emergency room. The GCS actually includes three response dimensions which therefore allow medical personnel to evaluate levels of consciousness when other aspects (such as vision or speech) are compromised by factors other than impaired consciousness. The GCS is also a good predictor of outcome.

The GCS is not without problems, however. Intoxicated patients are known to produce unreliable GCS scores. Many trauma patients initially remain lucid at the scene of the accident but then become agitated, for which sedation is required. Sedation, as with intoxication, may lower their GCS. As with other tests, the GCS is but one test to be taken into account.

Statistics vary on the outcome of individuals sustaining moderate traumatic brain injury. At least one study indicated that as many as 28% of those individuals seen in an emergency room and in an intensive care unit diagnosed with a moderate traumatic brain injury made a “good recovery” on the Glasgow Outcome Scale.

Changes in sleep patterns, fatigue, judgment, headache, multitasking, memory, concentration, word selection, attention deficits, processing speed problems, and problems with independent living were nonetheless found to persist. Most individuals sustaining moderate traumatic brain injury will find it extremely difficult to return to their pre-morbid vocation.

The specific area of the brain where damage occurs can likewise have an extreme impact on outcome. For example, where the injury is localized in the temporal lobes, seizure or temporal lobe epilepsy (TLE) can develop. Where the injury is primarily localized in the frontal lobes, frontal lobe syndrome can develop. Depending on whether the injury is focal or diffuse, and further depending on the area of the brain affected, the outcome of individuals sustaining moderate traumatic brain injury is difficult to predict, as are the clusters of symptoms likely to remain.

Statistically, severe traumatic brain injury victims comprise approximately 10% of all traumatic brain injuries. However, because individuals sustaining severe traumatic brain injury are unlikely to ever return to work or independent living, and because their rehabilitative needs are so great and expensive, and because almost all are unable to return to independent living, this group represents a growing problem for society and for the health care profession. Families of individuals sustaining severe traumatic brain injury are subjected to severe financial and emotional burdens.

As indicated above, where a patient sustains a PTA with duration from one day to seven days, their injury can be rated “severe”. (Note that where the PTA is between one to four weeks, the traumatic brain injury can be rated “very severe”, and where the PTA duration is for more than four weeks, the traumatic brain injury can be rated “extremely severe”).

As further indicated above, where the Glasgow Coma Scale score is found to be equal to or less than eight, or where coma duration is found to be greater than six hours, a rating of “severe traumatic brain injury” is appropriate.

Severe traumatic brain injury continues to have significant effects on emotional, cognitive, vocational, psychosocial, independent living, and family function decades after the injury. There is a distinct interplay between emotional components and organic injury that interplays and interacts cumulatively in effect.

Generally speaking, individuals sustaining severe traumatic brain injury display dysfunction in virtually all areas of cognition, and indeed display motor defects affecting physical response. While there may be some unique characteristics demonstrated, patient by patient, it is not uncommon for the following deficits to persist in varying levels of severity over the course of the patient´s life:

While the profile of motor problems varies from individual to individual, it is not uncommon to see problems in basic motor functions such as equilibrium, range of motion, abnormal or involuntary movements, primitive reflexes, and problems with sitting, kneeling, standing, walking or running. These problems may be more impaired during the early phase of the severe traumatic brain injury.

Of course, where the severity of brain injury or other insult has been significant enough to impose paraplegia and/or quadriplegia (with or without spasticity), entirely different motor function problems arise.

Individuals sustaining severe traumatic brain injury often experience:

• Decreased dexterity
• Decreased manual speed
• Increased reaction time
• Tremors
• Hemiparesis
• Decreased range of motion
• Contractures

A wide variety of rehabilitative care is usually employed over the course of the patient´s life in order to attempt to improve motor function.

Without question, the most devastating permanent disorder associated with severe traumatic brain injury is that of executive dysfunction, which involves an individual´s capacity for self control, regulation, self-direction, planning, organization, and self determination.

Frontal lobe functions as “executive” abilities. These can be summarized as capabilities necessary for goal formation, planning and organization, decision-making, and monitoring and altering behavior on the basis of performance. Where dysfunction occurs in executive abilities, extreme problems result. Frontal lobe functions include drive, mood, emotion, and personality. The frontal lobes are crucial for monitoring behavior.

Deficits associated with frontal lobe injury are often the most severe as they interfere with the ability to fluently utilize knowledge, appropriately or adaptively. Many behavioral problems seen in patients sustaining executive dysfunction are apparent to all.

Among them are signs of faulty capacity for self control or self-direction, including:

• Emotional lability or flattening
• Quickness to anger
• Tendency to irritability and excitability
• Impulsivity
• Erratic carelessness
• Rigidity
• Difficulty in making shifts in attention and ongoing behavior

Deficits associated with frontal lobe injury prohibit a person from engaging in independent behavior. Such individuals must live in a structured environment, and oftentimes need 24/7 attendant care.

Other defects in executive functions, however, are not so obvious. The problems they occasion may be missed or not recognized as neuropsychological by examiners who see patients only in the well-structured in-patient and clinic settings in which psychiatry and neurology patients are ordinarily observed. Perhaps the most serious of these problems, from a psychosocial standpoint, are impaired capacity to initiate activity, decreased or absent motivation (anergia), and defects in planning and carrying out the activity sequences that make up goal directed behaviors. Patients without significant impairment of receptive or expressive functions who suffer primarily from these kinds of control defects are often mistakenly judged to be malingering, lazy or spoiled, psychiatrically disturbed, or–if this kind of defect appears following a legally compensable brain injury–exhibiting a “compensation neurosis” that some interested persons may believe will disappear when the patient´s legal claim has been settled.

Individuals sustaining executive dysfunction through severe traumatic brain injury are often inert. It is not that they are physically incapable of performing certain tasks; it is instead the nature of the brain injury that stops them from performing the task.

Individuals sustaining executive dysfunction have processing speed problems and difficulty dealing with competing sources of information. They may be subject to “overload” in a stimuli bound environment. The greater these problems, the more socially dependent they become.