TRAUMATIC BRAIN INJURY (TBI)

Classification, Prognosis, & Severity

Classification

Closed head trauma is generally the result of acceleration/deceleration forces with or without impact of the skull (Bruce, 1990).

Usually, two types of injuries are seen with closed-head injury: focal and diffuse.

Focal damage is found at the area of impact and at the region involved in the rebound from the impact.

Both the coup and contrecoup injuries serve as localizers for the assessment of damage (Lezak, 1994).

Diffuse injury, on the other hand, is the result of shearing of white matter and grey matter.

This damage is generally caused by the stretching and distortion of the axons, and such neuronal disruption often results in coma.

Classification

Diffuse injury is most commonly seen in midline structures that are involved in the transfer of information.

Areas at risk include the corpus callosum, for transfer of information from one hemisphere to another, the internal capsule, for information running from anterior to posterior regions, and the cerebellum, for information responsible for balance and skilled movements.

In addition, damage is frequently seen in the region of the frontal lobes in the area of the eye sockets, and in the regions in front of the ears (the temporal poles).

Damage to these areas has been found to influence behavior, emotion, memory, and attention.

Classification

Penetrating injuries, also known as open-head injuries, involve perforation or fracture of the skull.

The meninges are frequently torn or lacerated. With projectiles, there is injury to tissue on both

sides of the projectile tract. Foreign substances (hair, skin, and bone

fragments) may be carried into the brain by the projectile.

Secondary infection due to the foreign materials in the brain must be monitored.

Severity of Head Injury

• There are variations in the severity of head injury, ranging from mild, to moderate, to severe.

• The Glasgow Coma Scale (GCS; Jennett & Teasdale, 1981) is frequently used to ascertain the level of head injury.

• The higher the score, the less impairment is present.

• The GSC has been validated extensively with adults, but has been reported to be less reliable for young, preverbal children (Lehr, 1990).

Nonetheless, the highest rates of fatality are for those patients with a GCS of 8 or less.

Level of Consciousness (LOC)• With either closed or open head injury, loss of

consciousness may vary between a few seconds to many days or months.

• Recovery from consciousness may be slow or sudden.• A patient’s level of consciousness (LOC) refers to the

ability to relate to oneself and one’s environment.• Assessing a patient’s arousal and awareness is

necessary to determine the LOC.• Arousal refers to the patient’s ability to react to

environmental stimuli whereas awareness refers to the ability to correctly interpret the meaning of stimuli.

Level of Consciousness (LOC)• There are five LOC, from most aroused to least

aroused:oAlertness—the patient is fully awake and fully

aware of normal external and internal stimuli. The patient is able to interact with the clinician in a meaningful way.

oLethargy—the patient is not fully alert and tends to drift off to sleep when not actively stimulated. Spontaneous movements are decreased and awareness is limited.

oObtundation—the patient is in a transitional state between lethargy and stupor. The patient is difficult to arouse and is confused when aroused. The patient usually requires constant stimulation.

Level of Consciousness (LOC)

oStupor and semicoma—the patient will respond to only persistent and vigorous stimulation. The patient cannot be aroused spontaneously and is able only to groan or mumble and move restlessly when arouse.

oComa—the patient is completely unarousable. The patient does not respond to external or internal stimulation.

Severity of Head Injury

The duration of impaired consciousness—the number of days from the time of injury until the individual is able to follow commands—is also used to gauge the severity of injury.

Mild injuries are those that result in a loss of consciousness or a posttraumatic amnesia (PTA) of less than 1 hour and a GCS score of 13 to 15.

Mild head injuries may be accompanied by headache, lethargy, irritability, withdrawal, and/or lability.

Such behavioral changes can persist and result in difficulties in school and within the family unit (Boll, 1983).

Severity of Head Injury

• Children under age 12 with minor head injuries have been found to show behavioral difficulties such as attentional deficit and low frustration tolerance even four years post-injury.

• Changes in IQ are very infrequent in children with mild TBI, although subtle complex language deficits and attention difficulties may be present for 6 months or longer after the injury has occurred.

• It is interesting to note that information processing difficulties constitute the most common type of deficit, and may partially explain the higher-than-expected number of children with minor head injury prior to age 12 being retained in a grade or placed in remedial classes.

Severity of Head Injury

When loss of consciousness or PTA lasts from one to 24 hours, and the GCS score is 9 to 12, the injury is considered to be moderate.

Symptoms that appear to persist over time, usually for several months, include headache, memory deficits, and behavioral difficulties.

Deficits are frequently found in the areas of problem-solving, memory, and attention/concentration.

Because of these problems, many patients with moderate head injuries experience difficulty in caring for their needs and, for adults, in maintaining employment.

Severity of Head Injury

Injuries that result in a loss of consciousness or PTA of more than 24 hours with a GCS of 3 to 8 are considered severe (Begali, 1992).

Patients with these injuries usually require immediate and intensive medical treatment.

Approximately 50% of children brought to ER with severe head injuries die.

• For those who survive, the deficits are more severe, both physically and neuropsychologically, than those of children with mild to moderate HI.

Upon recovery, many severely injured children and adolescents show intellectual impairment that does not resolve.

Severity of Head Injury

Achievement in school is often significantly compromised by deficits in the ability to name objects and/or pictures, in verbal fluency, and in the ability to take written notes.

Children are typically more impaired than adolescents.

Additional deficits in memory, attention, and organization are hallmarks of severe HI.

Prognosis

• The length of coma has been found to be associated with enduring cognitive impairment and the ability to return to school, with longer comas associated with poorer outcomes.

• For adults, recovery from HI is usually completed within 180 days of injury, with as much recovery as will be achieved almost always present within 6-9 months of injury (Lezak, 1994).

• For children, recovery from severe TBI can span five to six years postinjury.

• However, the first 12-18 months after coma is considered the most crucial period for recovery, as 85% of all cognitive and behavioral improvement is found in that period.

Prognosis

• Some children show significant improvements two to three years after injury.

• Age is an important variable in understanding the sequelae of TBI.

• Younger children show different patterns of recovery, and future learning is further affected because of their incomplete development.

Early injury has been found to be related to more significant later deficits than later injury.

The developing brain may be more vulnerable to damage because of the rapid growth spurts that occur in the early stages.

Prognosis

In general, damage prior to age 1 appears to result in significant impairment, whereas damage between ages 1 and 5 allows for the reorganization of functions and recovery of language ability.

Children experiencing TBI in infancy have more receptive and expressive language problems that those with TBI as toddlers.

Expressive language skills are also more susceptible to early TBI than receptive language.

Damage occurring after age 5 is quite significant and may impair the normal process of brain development.

Prognosis

• Children with severe HI are more likely to continue to show intellectual impairment as compared with adolescents with the same extent of damage.

• Structures that do not generally develop until later in life may be compromised by early damage.

• Children with severe HI will continue to evidence memory and language deficits even after successful school reentry, and may exhibit severe learning difficulties years after injury which were not initially apparent.

• Tasks that involve frontal lobe and association areas of the brain—areas that do not assume adult-like functions until 12 years of age or later—are particularly vulnerable to early injury.

Prognosis

• These frontal areas monitor behavior and allow a person to change behavior according to the situation, and association areas allow for the integration of information from various modalities (visual-motor, visual-spatial, auditory-visual, etc.).

• Preadolescents with TBI have less improvement in writing than older adolescents with TBI.

• Similarly, recovery in motor and visual-spatial tasks was found to be slower in younger adolescents than in older adolescents.

Initial Symptoms of TBI

On regaining consciousness, the patient with TBI may exhibit:o Inconsistency;o Disorganization;o Disorientation to time and place;o Confused, slow, or inappropriate speech;o Restlessness;o Irritability;o Inattentive behavior, distractible behavior;o Cognitive impairments, including loss of memory,

judgment, and abstract reasoning skills;

Initial Symptoms of TBI

o Generally poor control over emotional responses;o Aggressive behavior (in some cases);o Anxiety (in some patients);o Socially inappropriate behavior;o Slow reaction time;o Paranoia (in some cases)o Lack of self-appraisal of deficits;o Lack of purposeful behavior;o Lack of self-care skills, needing constant

supervision and assistance; and o Stepwise recovery (periods of little or no

improvement alternated with rapid improvements).

Early Symptoms of Recovery In the early days of coma recovery, there is a

gradual improvement in most symptoms, including:o Clearing up of confusion;o Improved orientation to space and time;o Improved social awareness;o Improved control over emotional responses;o More appropriate responses to simple questions.o Slow re-emergence of some of the self-care skills,

although still needing assistance and supervision;o Re-emergence of more purposeful behavior; ando Progressively more independent functioning in routine

situations.

Early Symptoms of Recovery Other symptoms, although showing signs of

abatement, may still be present:o Irritability, restlessness, shorter attention span, poor

control over emotions, aggressive tendencies, impulsivity, and slow reaction time.

Cognitive deficits may be noted in:o Poor judgment;o Memory (pre-traumatic and/or post-traumatic amnesia);o Problem solving skills;o Abstract reasoning;o Distractibility;o Inattention; and o Slower reaction times.

More Persistent Symptoms

• Generally, significant recovery of many cognitive and communicative skills will be noted within the first two months, with continued improvement for up to one year.

• Persistent physical difficulties related to the severity of the injury may be noted in limited or impaired use of hands and limbs, and visual or other sensory deficits.

• Mild to moderate disability may continue to be noted with:o Problem solving skills;o Abstract reasoning;

More Persistent Symptoms

o Distractibility;o Inattention; and o Slower reaction times.

In terms of visual and perceptual skills, areas of difficulty may include: o Problems in drawing;o Visual-spatial deficits;o Construction impairment; ando Attentional deficits.

More Persistent Symptoms

• Communication problems may be less pronounced than attentional, cognitive, emotional, and general behaviors deficits.• Nonetheless, individuals with TBI may exhibit

residual dysarthria, especially in patients with brainstem or cerebellar involvement.• The dysarthria may range from mild

articulatory problems (especially imprecise consonants) to severely unintelligible speech.• Varying degrees of dysphagia may be present.

More Persistent Symptoms

• Other speech impairments such as apraxia of speech and reduced rate of speech may be observed.• In terms of language, confused language and/or

aphasic-like symptoms may be observed in the initial stages and may ameliorate with time.• If patients are very confused, bizarre, inappropriate,

incoherent, and paraphasic language will be evidenced.• In extreme cases, mutism or aphonia may result.• Other areas of difficulty are found with auditory

comprehension of spoken language, word finding problems, and residual spelling errors in writing.

More Persistent Symptoms

• Impaired pragmatic features of language include difficulty in conversational turn-taking and topic maintenance.• Prosodic impairments include difficulty in

monitoring rate, pitch, and vocal loudness.

Assessment and Classification

TRAUMATIC BRAIN INJURY (TBI)

Goals of Assessment

• The goals of assessment depend upon the period of time since onset of the head injury.• In early stages (acute) following neurological

onset, an initial, brief assessment is made at bedside.• Once the patient’s physical condition

improves and stabilizes medically, the goal is to make a more thorough assessment of communication and cognitive skills.• In general, the goals of assessment with TBI

include:o assessing communication deficits; o evaluating the strengths and limitations that

might help in planning treatment;

Goals of Assessment

o evaluating communication deficits in relation to cognitive, sensory, and physical deficits; and

o evaluating the need for AAC.• If you suspect aphasia, assess expressive,

receptive, and gestural communication, in order to identify initial treatment targets.

• If you suspect a right hemisphere disorder, you will want to evaluate for perceptual and attentional deficits, and assess communication disorders associated with right hemisphere syndrome.

Assessment Protocol

Using the patient’s medical chart, look for the following information:o patient’s medical diagnosis;o current and future medical treatment plan;o medical prognosis;o current medications and their side effects;o radiologic and brain imaging data;o reports from other professional on cognitive impairment,

intellectual functioning, emotional and behavioral disorders/deficits, and motor and sensory impairments.

Assessment Protocol

• Once you have reviewed the chart, make a brief and initial bedside evaluation.

• Create your own procedure or administer a standardized test to:o Assess simple responses to verbal commands, e.g., “open

your eyes;” “move your feet;” “wiggle your toes;” “nod your head;” “raise your hand;” and “move your fingers.”

o Assess the presence or absence of verbal responses, noting the speed, relevance, and appropriateness of all responses given.

o Note whether the patient can:o say “Hi;”o give single word-responses, and if so, the kinds of words

produced;

Assessment Protocol

o use sentences, and if so, the types of sentences;o respond spontaneously, noting the type and length of

utterance spontaneously produced;o respond only to question and commands;o respond only nonverbally, but appropriately;o respond verbally, but not successfully;o not respond in any way.

• Assess simply memory skills and basic orientation, using something like the Galveston Orientation and Amnesia Test (GOAT) to assess orientation to person, place and time, and memory before and after injury.

Assessment Protocol

• The GOAT can be administered daily and/or weekly to assess improvements in orientation and to determine when post-traumatic amnesia has ended.

• When the patient’s initial symptoms subside, assess cognitive deficits, specifically:o Memory deficits;o Attention span and distractibility;o Reaction time; ando Visual and perceptual deficits.

• In addition to the GOAT, subtests from other cognitive and/or aphasia assessment tools can be used to examine word recall, paragraph recall, both immediate and delayed.

Assessment Protocol

Attention span and distractibility can be observed during assessment and interview.

Lack of attention may be evidenced by the need to repeat instructions, the need to re-present test items, the need to repeatedly give alerting stimuli (e.g., “look at this picture”).

Note response to extraneous stimuli such as people passing by and noise.

Note fatigue during assessment and how fast it occurs.

Reaction time can be judged by the speed at which a patient responds to questions, both in structured and spontaneous tasks.

Assessment Protocol

Visual and perceptual deficits can be assessed by asking the patient to copy simple line drawings, geometric figures, and common items from memory (face, cup, pencil).

With respect to communication problems, assess whether or not a motor speech disorder, dysarthria or apraxia of speech, or both, is present.

Assess rate of speech and its affect on intelligibility. Assess confused, bizarre, inappropriate, and

incoherent language.

Assessment Protocol

• Assess problems in auditory comprehension of spoken language.• Assess persistent word-finding problems.• Assess syntactic and morphological features

informally during a conversational speech (discourse) sample.• Assess pragmatic features of language, making

judgments as you interview the client and while eliciting a conversational speech sample about such behaviors as conversational turn-taking and topic maintenance. • Assess prosodic behaviors, such as rate, pitch, and

vocal loudness.

Assessment Protocol

• Assess writing, looking at spelling, spacing, orientation of writing to page.

• Assess related problems such as dysphagia, and sensory disabilities.

• For children and adolescents with TBI, additional academic testing may be appropriate: assess reading, writing, and literacy skills to determine the child’s strengths/limitations and to suggest a treatment plan that will facilitate the child’s academic achievement.

• The following table lists the few TBI instruments that are most frequently employed for more standardized testing.

Assessment Instruments Utilized for TBI

Test PurposeGlasgow Coma Scale To make a bedside

screening of general awareness and responsiveness.

Galveston Orientation and Amnesia Test (GOAT)

To make a bedside screening of memory and orientation.

Weschler Memory Scale-Revised

To assess memory skills.

Ranchos Los Amigos Scale of Cognitive Levels

To assess cognitive and behavioral level and recovery.

Assessment Instruments Utilized for TBI

Test PurposeCommunicative Abilities in Daily Living (CADL-2)

To assess functional communication skills.

Brief Test of Head Injury (BTHI)

To assess orientation and attention, following commands, linguistic organization, reading comprehension, naming memory, and visual spatial skills.

Scales of Cognitive Ability for TBI (SCATBI)

To assess perception/ discrimination, orientation, organization, recall, and reasoning.

Assessment Instruments Utilized for TBI

• Once cognitive, communicative, and academic assessments have been completed, these data should be analyzed and summarized relative to physiologic and neuromotor problems.

• They should also be integrated with findings from medical-neurologic and neuropsychological (usually in a team meeting) to obtain a comprehensive profile of the patient’s level of functional recovery (Ranchos Scale).