brain injury + spinal cord injury Flashcards
definition of traumatic brain injury?
anything that affects the skin, skull, or brain
causes of traumatic brain injury?
Blunt trauma caused by an object or falling, motor vehicle accident, sporting activities, violence, child abuse
groups at risk for traumatic brain injury?
elderly, young adults, men, falls (toddlers)
what is the leading cause of death and disability among children?
head injury
what is a penetrating injury?
penetrating injury (open injury)
- skull is not intact
- brian / meningies is exposed
- involves skull fracture with penetration of the dura matar and possibly brain tissue
- requires surgery to debride, clean, remove clots, prevent infection
- area of damage is localized to the path of the object
what is a blunt injury?
blunt injury (closed injury)
- more common
- brain tissue remains covered
- rotational injuries
- acceleration/deceleration injury
- skull remains intact
- no external damage evident
- brain / meninges not exposed
what are the two types of traumatic brain injury?
1) Focal:
- generally associated with direct impact to the head
- specific, localized injuries to the brain
2) Diffuse:
- widespread, not limited to a localized area
- difficult to detect and treat
what is included in focal brain injuries?
- skull fractures
- contusions
- hematomas (epidural, sudbural, intracranial)
what are the types of skull fractures?
1) Linear (crack in skull)
2) Depressed (makes a dent in skull and depresses brain- causes ICP)
3) Basilar (basal) - is a break of a bone in the base of the skull.
- CSF leaks from nose or ear
- periorbital bruising (around eyes)* sign of this fracture
- battles sign (bruising behind ear)
- because meningies is torn, these ppl have high risk for meningitis
what is the halo sign?
The “halo” or “double-ring” sign is a classic image in medicine and was taught as a method for determining whether bloody discharge from the ears or nose contained cerebrospinal fluid (CSF).
-its a ring of fluid around the blood stain
what is a contusion?
-the bruising of brain tissue
-frequently located on frontal and temporal lobes
-often are “” injuries
“coup’ = intital bruise made
“contrecoup” = bruise that occurs after (rebound bruise) second impact
what kind of changes can occur if the frontal lobe is damaged?
-behavior, personality changes, motor deficits, organizing, planning, problem-solving, attention, motor cortex
what can be affected if the temporal lobe is damaged?
speech and hearing, language recognition, long-term memory, intellect, emotion
what is coup-contrecoup?
when the brain moves inside the cranial cavity and collides with cranial surface
- bounces backward from the point of impact, colliding with the opposite wall of the skull
- may result in two focal injuries or diffuse axonal injury throughout
- the initial “coup” is relatively small
what is a hematoma?
an accumulation of clotted blood within the tissues (big blood clot within the brain
- classified according to location:
1) Epidural (outside the dura)
2) Subdural (underneath the dura)
3) Intracerebral (within the brain tissue)
whats the difference between epidural and subdrual hematomas?
-both increase pressure in the brain and are both potentially fatal
Difference:
Epidural: blood vessels here are mosly arteries (arterial soruce of bleeding, so hematoma will accumulate faster (will have an initial loss of conciousness and then regain conciousness) followed by sudden but fast decline and another loss of consciousness
Subdural: blood vessels in this space are mostly veins, so accumulates slower
impact to where can induce an epidural hematoma?
impact to the temporal area
what happens to the arteris when force of impact is transfered to the brain?
arteries are sheared
what are more common, epidural or subdural hematomas?
subdural are more common
where is the subdural hematoma located?
it is the accululation of blood between the dura and arachnoid layers of the meninges
signs and symptoms of an acute subdural hematoma?
- headache
- drowsiness
- confusion
- slowed thinking
- agitation
what is an intracebral (within brain) hematoma?
Accumulation of blood in parenchyma of brain tissue rather than between the menigies
- results from trauma with high-impact blow to the head
- Signs and symptoms depend on location and may include headache, decreasing LOC, dilation of one pupil, and hemiplegia
onset of epidural hematoma?
(arteries)
- immediate to delayed 2-3 hours.
onset of subdural hematoma?
delayed onset (few hours to 1 week after injury)
what is a diffuse brain injury?
- widespread damage to the brain
- difficult to detect / treat because only seen on electron microscope (involes numerous axons)
- shreading forced applied to the brain
- whiplash, rotational, twisting injuries
- most severe injuries are loacted more peripheral to the brain stem, causing extensive impairments
- axonal damage can only be seen with electron microscope
- results from diffuse forces, severe shaking, rotational forces
what are the two types of diffuse brain injuries?
- concussion
- diffuse axonal injury
what is a concussion?
transient neurological dysfuntion due to a traumatic impact
two types:
1) Mild concussion (no loss of consiousness)
2) Classic cerebral concussion -loss of consiousness (for up to 6 hours)
Manifestations of concussion?
Headache, confusion, disorientation, dizziness, visual distrubance, vomting, nausea, possible loss of conciousness
-memory deficits (retrograde amnesia or anterograde amnesia)
what is retrograde amnesia?
- loss of memory of past events
what is anterograde amnesia?
difficuty forming new memories
what is postconcussive syndrome?
- headache, anxiety, irritability, insomina, difficulty concentrating, and depresssion
- this may persist for weeks or months
- long term effects of having a concussion
- hockey, football, and soccer and the highest risk sports
what is chronic traumatic encephalopathy?
- post concussion
- progressive degeneration of brain tissue
- accumulation of abnormal protein called tau
- can begin months, years, or even decades after the last trauma
- associated with memory loss, confusion, imparied judgement, impulse control problems, agression, depression, and eventually progressive dementia
what is diffuse axonal injury?
Diffuse axonal injury (DAI) is a brain injury in which extensive lesions in white matter tracts occur over a widespread area.
It occurs in about half of all cases of severe head trauma and may be the primary damage that occurs in concussion.
-occurs when shearing forces disrupt the structure of neurons and thier nearby blood vessels
-diffuse damage to axons
-stretching or shearing of neuronal axons
-meeting of grey and white matter is weak, so tearing of neurons occurs here
-outcomes are unpredictable
-high morbidity and mortaility
physical, cognitive, and behavioural effects of diffuse axonal injury?
physical: paralysis swallowing disorders, visual, auditory, taste, and smell impairments
cognitive: disorientation, confusion, memory, judgement behavioural: agitation, impulseivness, withdrawl, depression
where does the greatest density occur?
-the worst injury occurs where the density difference is the greatest (farther away from the brain stem)
why are infants at risk for diffuse axonal injuries?
shaken baby syndrome
-high water and gelatious content of babys brain make then very vulnerable to injury during shaking
-larger head proportionately and weaker neck muscles
1 in 4 shaken babies die from there injuries
-signs and symptoms: include vomiting, poor feeding, bradycardia, enlarged frontal, seizures
what are some potential long-term outcomes of traumatic brain injury?
- full recovery or recovery with residual disability
- impact on family job, social, community interaction
- cognitive, memory, sttention, emotional, personailty, behaviour, social skills (frontal lobe injury)
- speech, comprehension disorders:
- Aphasia, dysphasia, agnosia.
- depresssion, anxiety, substance abuse
- motor function, posure, muscle tone, gait, swallowing
- dyskinesia, akinesia, hyperkinesia, bradykinesia
- hypertonia, hypotonia (muscle tone)
- dysphagia
what is aphasia?
inability to communicate by speech
what is dysphasia?
imparied ability to communicate by speech
what is Agnosia?
Cannot comprehend sensory input (cant interpret sounds, cant identify fingers of thier own hands or others hands, cant interpret images, cant distingish objects by touch)
what are some long term changes in levels of consiousness?
- persistant vegitaitive state
- irreversible coma
- brain death
what is persistent vegetative state?
-can be aroused but no awareness
-sleep / wake cycles are present, can open eyes spontaneously, breathing, heart rate are present and nor mal.
cannot track objects, cannot follow commands, unable to communicate, incontinence
cannot communicate with words
what is a irreversible coma?
aka cerebral death
- no arousal or awareness, but brain stem is intact
- death of cerebral hemisphere, but brain stem and cerebellum still ok.
- no eye opening
- no voluntary movement
- cant wake up, cant interact
what is brain death?
-everything is dead, including brain stem
what people are at risk for spinal cord injuries?
Men, age 34
- MVA, sports, violence, fallts
- elderly and very young
what is a flexion injury?
(head is bent forward)
- blow to the back of the head, diving accidents, front impact motor vehicle collisions
- fractures the vertebrae anteriorly, causing anterior cord injury and disruption of posterior ligaments
what is an extension injury?
–head os bent backward)
hit from back of head, rear impact, falls, hits chin on something
-disrupts anterior ligaments, may fracture the spinous process.
what is a compression injury?
-falling straight down on booty/tail bone
-or diving into a pool and landing on head
affects T12 - L2
what is a flexion- rotation injury?
- MVA
- tear the posterior ligaments
what happens in the spinal cord when it is injured?
- cellular injury
- inflammation
- edema
- decreased tissue perfusion
- tissue hypoxia
- necrosis
- scarring (this can cause interruption of transmission up and down the spinal cord)- cannot transmit action potentials
where will edema be located on the spinal cord?
at the level of injury and 2 cord segments aboe and below the site on injury
- from edema comes decreased tissue perfusion due to increased pressure, results in ischemia, hypoxia, and more necrosis
- ciculation will return to white matter in 24 hrs but not grey matter
why is it hard to determine short term or long term consequences of the spinal cord injury?
-need to let swelling resolve first to then determine consequences.
-takes about 6 weeks and can last up to as long as 3 months
(pt has to wait a long time to find out if they can walk again)
what is spinal shock?
Spinal shock is the temporary reduction of or loss of reflexes following a spinal cord injury (SCI)
- flaccid paralysis below the injury
- loss of reflexes below the injury
- lasts 7 days to 3 months
- cessation of normal activity of neural cells at and below the level of the injury
- paralysis and flaccidity of muscles
- loss of bowel and bladder control
- poor temp control
- loss of pain, touch, pressure,
- paralytic ileus with distension
- unstable BP
- possible respiratory impairment
what are the 4 possible levels of injury?
-cervical, thoracic, lumbar, sacral OR quadriplegia (all 4) - at or above C7 OR paraplegia (paralysis of legs only)- below C7
what are some possible complications of a spinal cord injury?
- neurogenic shock- can be life threatening, occurs at T6 or higher, losso fo tone in arterioles, so they dilated. blood pressure in these arteriols goes up, imparies tissue perfusion. pt experiances slow heart rate
- respiratory failure: can be life threatneing. injury at C4 or higher. paraylsis on frenic nerve can affect diaphram, therfore affects repiratory function
- autonomic dysreflexia- potentially life threatening, abnormal reflexes of sympathetic and parasympathetic systems.
what is automonic dysreflexia?
- a complication of spinal cord inury with injury ABOVE T6
- disconnect of sympathetic and parasympathetic systems
- assocaited with disconnect between the SNS and PNS
- hypertension above the injury (triggers baroreceptors -> bradycardia and vasodilation)
- vasocontriction below injury causes increased blood volume above the injury
- SNS vasocontriction
- pale below injury, red above injury
- severe hypertension of upper extremeties
treatment of automonic dysreflexia?
- remove/ prevent noxious stimuli: vasodilators, antihypertensives
