TBI Flashcards
Acquired Brain Injury (ABI)
General term that categorizes any sudden non-progressive injury to the brain that occurs after birth and may be result of trauma, anoxia (near drowning), or non-traumatic event (Stroke, tumor, infection)
M/c cause of: morbidity and mortality in children and young adults and acquired disability
Recovery of function may occur
Epidemiology
M/c cause of injury is MVA and falls
Incidence higher in boys and highest in boys btwn ages 15-20 and 6-10 y/o
Demographic and socioeconomic factors: poverty, crowded neighborhoods, family instability, hx of drug/alcohol abuse, and learning disability
Behavioral characteristics: impulsivity, ADD/ADHD
Primary Brain Damage
Forces that occur at time of initial impact
Classified by MOI: acceleration/deceleration, crush injury, penetration injury
Secondary Brain Damage
damage that occurs as result of processes evoked in response to initial trauma
Results from hypoxia or ischemia caused by intracranial and extracranial factors (hypoxemia or hypotension)
Further brain damage may occur d/t complications like infection, hydrocephalus, hygroma (collection of CSF in dural membrane), convulsions
Infection may occur after fracture or CSF rhinorrhea or may be caused as a result of intracranial monitoring or surgery
Acceleration/deceleration Injury
Primary brain damage
Force applied is transitional or rotational
Common result of MVA, head hitting immobile object, or mobility objects hitting immobile head
Lesions can be microscopic or combined with focal macroscopic lesion with predilection for the midbrain, pons, corpus callosum, and white matter of the cerebral hemispheres
Rotational injuries result in differential displacement of adjacent brain tissue
Shearing forces has greatest effects in areas where the density differences of the tissue are greatest
2/3 of this injury type result in diffuse axonal injury (DAI), occurring at gray and white matter interface
Child’s brain has greater water contract than adult brain –meaning brain is softer and more prone to acceleration/decel injuries
Contusion or Crush Injuries
Primary brain damage
usually frontal or temporal
result from low velocity impact such as blows to the head or falls
Skull fx may be associated–significant only when underlying compression of brain or hemorrhage occurs OR more small intracerebral hemorrhages and occasionally more extensive bleeding may be observed
Penetration injury
Primary brain damage
minority of TBI in kids
Non-missile injury- children more prone to this injury, results from fall or from home/playground accident. Often involve nails, pencils, sharp sticks—most cases cause focal damage
Missile Injury- gunshots, air pellets, lead to substantial intracranial damage
Intracranial Factors of Secondary Brain Damage
hemorrhage- d/t laceration of blood vessels within brain on on surface–> results in epidural, subdural, or subarachnoid hematoma
Brain swelling- displacement of brain occurs d/t increased ICP due to edema or caused by mass lesion
- Diffuse swelling more common in infants and children than adults d/t increased compliance of skull allowing for cranial shape changes and more diffuse pattern of brain damage
Posttraumatic Seizures
3 types depending on type and time of onset related to trauma
Immediate Seizure: within minutes
Early seizures: occur w/in 1 wk of trauma
Late Seizures: beyond 1st week of injury
Child who experiences 2 or more late seizures = dx with posttraumatic epilepsy
Prognosis
Severity of TBI is directly correlated with outcome
Use GCS to determine severity of injury
Coma duration classifies injury severity, depth and duration of coma are negatively associated with outcome
Mild = coma lasting less than 20 minutes
Moderate = coma lasting 20 minutes to 6 hours
Severe = coma lasting 6-24 hours
Very Severe = coma longer than 24 hrs
Longer the coma = less likely is good recovery, longer than 4 weeks - poor recovery
Coma duration may predict motor and cognitive recovery
Highest mortality rate is in children 2 and younger with second peak at 15 y/o
Death is seldom due to primary damage and more often a result of secondary brain damage
Post-traumatic Amnesia (PTA)
period of variable length after trauma where pt is confused and disoriented
Retrograde- inability to recall new information
Longer the duration of PTA the worse the outcome
Unlikely that a person will have severe outcome if duration of PTA is less than 2 months
Greater than 3 months unlikely to have good recovery
