week 11: TBI & coma scales

what is a TBI?

an acquired injury that is not degenerative or congenital caused by force

what are the 2 types of forces that can cause a TBI?

- external blunt force

- penetrating external force

are TBIs more likely to be in men or women?

men

what are the typical causes of a TBI?

- falls

- MVAs

- trauma/assault

- other

what are the 3 different categories of TBIs?

- closed head injury

- open head injury

- blast injury

what is a closed head injury?

- skull remains intact

- caused by impact of external blow

- bleeding in intracranial cavity

what is an open head injury?

- skull fractured or foreign object penetrates skull

what is a blast injury?

- relates to initial shock wave of blast

what is the primary phase of a TBI?

focal vs. diffuse axonal injury

what are focal lesions?

- contusions or lacerations

- may be anywhere

- may affect cranial nerves (ex. olfactory or optic)

what are diffuse axonal injuries?

brain moves inside skull typically from acceleration and deceleration with rotations (whiplash)

what can happen in diffuse axonal injuries?

- loss of consciousness due to axonal damage to brain stem

- causes damage to soft tissue of brain

what happens if the brain stem is damaged in a diffuse axonal injury?

vegetative functions

what happens if the reticular formation is damaged in a diffuse axonal injury?

consciousness may be lost (responsible for consciousness)

what are the components of the secondary phase/effects of a TBI?

- changes in cerebral blood flow

- intracranial hypotension

- increased cranial pressure

- intracranial hemorrhage

- intracranial infection

- hematoma (epidural, subdural, intracerebral)

what are some associated conditions with TBIs?

- anterograde amnesia = "after' memories lost

- retrograde amnesia = "before" memories lost

- post-traumatic epilepsy

- post-traumatic hydrocephalus

- chronic traumatic encephalopathy (CTE)

what do TBI symptoms depend on?

- cause of injury

- area of brain injured

- extent of injury

what do the TBI symptoms result in any combination of?

- cognitive impairment

- emotional and/or behavioral change

- physical symptoms

what are the 2 common positions seen in someone with a TBI?

decorticate and decerebrate

what does the decorticate positioning look like?

flexed position (internal rotation of legs, feet plantar flexed, arms abducted and flexed)

what does the decorticate position indicate damage of?

damage to the cerebral hemispheres (cerebrum)

what does the decerebrate positioning look like?

extended posturing (extended legs, feet plantar flexed, arms adducted, extended and pronated)

what does the decerebrate positioning indicate damage of?

damage to the brainstem

what are the symptoms of post concussion syndrome?

- headache

- dizziness

- vomiting

- sleep disturbance

- irritable

- personality changes

- memory problems

- depression

- decreased attention span

what are the stages of a TBI?

- stage 1 = motor control and perceptional implications (movement, coordination, balance)

- stage 2 = communication effects (speech and language)

- stage 3 = cognitive changes (memory, attention/concentration, judgment, problem solving)

- stage 4 = personality changes and affective response (personality changes, anger/irritable, depression)

what are the TBI severity levels?

- mild

- moderate

- severe

what does a mild TBI look like?

- unconsciousness

- memory loss

what does a moderate TBI look like?

- initial unconsciousness

- glasgow coma scale 9-12

what does a severe TBI look like?

- unconsciousness > 6 hours

- glasgow coma scale 8 or less

how does a person measure the severity of a TBI?

- glasgow coma scale (GCS)

- ranchos los amigos cognitive scale

- disability rating scale

- coma recovery scale-revised (CRS-R)

what is the glascow coma scale (GCS)?

- rates the seriousness of a TBI

- higher scores = better, less severe

what are the different parts of the glascow coma scale (GCS)?

- eye opening (1-4; none to spontaneous)

- verbal (1-5; none to oriented)

- motor (1-6; none to follows commands)

what is the best and worst score of the glascow coma scale (CGS)?

best = 15

worst = 3

what is the Ranchos Logos Amigos Cognitive Scale?

- assess levels of arousal and cognitive functioning (levels 1-10)

what does the initial management of TBI consist of?

- stabilize condition typically ICU to minimize brain swelling and optimize cerebral circulation/oxygenation

- prevent additional injury

- neurosurgical procedures sometimes

what are some forms of post-acute management and rehab for TBIs?

- therapy

- cognition

- neurology

- neuropsychology

- medications

- nutrition management

what are the different levels of the membranes/meninges covering the brain?

- dura mater

- arachnoid mater

- pia mater

what are some functions of the frontal lobe?

- organization

- motor

- personality

- reasoning

- initiation

- abstract thinking

what are some functions of the parietal lobe?

- sensory area

- awareness of body

- visual attention

- some memory functions

what are some functions of the temporal lobe?

- hearing

- memory

- organization/sequencing

- understanding and producing speech

- some aspects of visual perception

what are some functions of the occipital lobe?

- vision

what can injury to the cerebellum cause?

- inability to make rapid movements

- poor fine motor coordinations

- balance

- slurred speech

- dysphagia

- tremor

- ataxia

what is the function of the thalamus?

sensory information

what are the functions of the hypothalamus?

- hunger

- thirst

- sexual response

- temperature

what are the structures/functions of the limbic system?

- basal ganglia

- amygdala (fight or flight)

- hippocampus (learning and long-term memory)

what are the 3 parts of the brainstem and what is the function of the brainstem?

- 3 parts (midbrain, pons, medulla)

- relay station between brain and spinal cord