SCI - TBI 1

  1. 2 mill cases annually
    500,000 hospitalizations
    % that are severe? % w mild disability?
    • severe: 15%
    • mild disability: 30-50%
  2. av age for TBI, highest incidence ages?
    • av: 30
    • high: 15-24(risk seeking behavior), and 5 (abuse)
  3. TBI can be this or that...
    • it's a process, not an event, soo...
    • primary or secondary
    • open or closed
    • focal or diffuse
  4. 4 main mechanisms for TBI (mind you, they don't happen in a vacuum - one leads to another)
    • brain contusion
    • increased intracranial pressure
    • diffuse axonal injury (sheering)
    • stroke (ischemic a/o hemorrhagic - happens 2/2 injury -- not same as an embolic stroke)
  5. define brain contusion
    • cell death w hemorrhage (blood leak)
    • affects the soft brain tissue
    • can occur at site of impact or distal sites (coup contre-coup)
  6. what does he mean by "closed (non penetrating) injury?" - how does this kind of event hurt the brain?
    • no skull fracture
    • this injury results in diffuse deficits bc the sharp edges of dura matter cut into brain as the brain bounces around
    • can have coup contre-coup
    • accel/decel of brain --> sheering forces on brain
  7. open-skull fracture - correlates w what? 2 types?
    • intracranial hematomas
    • displaced: depressed
    • non-displaced: linear
  8. who gets a "lucid interval"
    • someone with primary brain damage due to an epideral hematoma  - the bleed pushes the dura into the brain
    • seen in a skull fracture that's associated w superficial vessel laceration
  9. what's a lucid interval?
    • loc, conscious, loc
    • can be dangerously misleading
  10. what's hppening in  subdural hematoma in primary brain damage?
    • bleeding from vessels btwn the dura and the brain (blood gets into brain)
    • leads to compression syndromes
    • seen w accel/decel injuries
    • high mortality rate
  11. 3 intracranial contents, their %s, why each might increase
    • brain: 80% - swelling/edema
    • CSF: 10% - accumulation if the roads out get blocked
    • blood: 10% - hemorrhage
  12. if the intracranial contents increase, where does the brain go?
    • down the foramen magnum
    • bad bad bad: brainstem gets compressed in there, breathing stops, living stops.
  13. does axonal injury happen in open or closed injuries?
    yes. either. can happen w/wo skull fracture
  14. name one major cause of persistent vegetative state
    diffuse axonal injury
  15. what's the most common structural abnormality in TBI?
    • diffuse axonal injury -- this is a sheering, stretching force to the axons, it alters their transmission
    • can cause mild to fatal deficits
  16. why might a TBI pt have an ischemic stroke?
    swelling compresses nearby arteries --> decreased O2 delivered to brain
  17. why might a TBI pt have a hemorrhagic stroke?
    • decreased O2 delivery bc blood is leaking into brain tissue, not entering capillary network
    • can be a primary or a secondary injury
  18. what kind of damage in "secondary brain damage"
    systemic, not focal damage
  19. causes for secondary brain damage - I'm not sure if these are 3 different issues or a stream of events
    • airway obstruction or trauma --> arterial hypoxemia
    • brain loses ability to autoregulate vasodilation/constriction
    • cerebral hyper/hypoperfusion
  20. the cytotoxic edema in secondary brain damage - what is it? how fast does it happen?
    • swelling of all cellular elements of the brain
    • if there's acute cerebral ischemia, within minutes there'l be swelling of neurons, glia, and endothelial cells
  21. sodium and ATP role in secondary brain damage's cytotoxic edema?
    ATP-dependant ion transport fails ----> rapid accumulation of sodium within cell --> water follows to maintain equilibrium
  22. what's the story with vasogenic edema as seen in secondary brain damage?
    • w massive injury there can be increased permiability of brain capillary endothelial cells, leading to increased extracellular fluid volume
    • ... can lead to a downward brain herniation
  23. which edema comes first?
    acute hypoxia --> cytotoic edema ... hours to days later vasogenic edema as infarctin develops
  24. how much of an increase in ICP is ok?
    • this slide is confusing, but I think if it goes up 5-10 mmHg, needs surg/med help
    • norm is 7-15 mmHg, says wikipedia
  25. 2 ways to deal w hihg ICP
    • decompressive craniotomy
    • steroids to reduce swelling
  26. coma - a general term meaning unresponsive to stimuli. Define the more specific terms -- "normal consciousness," "stupor," "obtundity," "delirium"
    • nc: arousal and cognition are fine
    • stupor: arousable only by vigorous stim
    • obtundity: slow/delayed response to stim
    • delirium: misinterpretation of stim, can't understand what a stim means
  27. when is a glasgow comma scale used
    in field and at 24 hrs
  28. glasgow coma scale - 3 fields it looks at?
    • eye
    • motor
    • verbal

    (it is "predictive but not localizing")
  29. glasgow coma scale scoring?
    • 3-15
    • get a 1 in each arena for having no response, and then more points the more responsive
    • 8 or less is a coma and needs long term care
  30. scoring fr the motor response in the glasgow coma scale (and what #2 and 3 mean)
    • 6 - obeys command
    • 5 - localizes - can id stim and push it away
    • 4 - withdraws from noxious stim
    • 3 - decortiate posturing - ext except flexed elbows
    • 2 - decerebrate posturing - ext
    • 1 - no response
  31. decerebrate vs decorticate posuring
    • both: extended legs, IR, PF, arms add, wrists pronated and fingers flexed
    • decorticate: elbows flexed (3 on CGS) (hands by the core)
    • decerebrate: elbows ext (2 on GCS) ("re" - so repeat the extension, do it in yr elbows too)
  32. glasgow coma scale verbal scoring
    • 5 - oriented
    • 4 - responsive-disoriented -- knows she's disoriented
    • 3 - inappropriate - speaks intelligibly, but nonsens
    • 2 - moans - beware tho- could be dysarthria
    • 1 - no response
Author
shmvii
ID
220544
Card Set
SCI - TBI 1
Description
spring 2013
Updated