26. Trauma Flashcards
(34 cards)
definition of contact injury?
kinetic energy applied directly to skull and brain
examples of contact injuries?
skull fractures, epidural hematomas, gunshot wounds
two types of skull fractures?
open/closed
closed skull fracture treated how?
most will heal without treatment
open skull fracture: main concern?
infection. elevation, debridement are impt.
epidural hematoma: associated with what kind of injury?
fracture, usually to temple/MMA
epidural hematoma: depressed level of consciousness is often due to what?
the hematoma itself. removal of the hematoma usually improves consciousness.
what is unusual about gunshot wounds?
different from other contact injuries because total KE is MUCH higher than with other contacts (baseball bat, for example)
what are 2 prognostic factors for gunshot wounds?
level of consciousness,bullet trajectory (bihemispheric is worse)
what underlies most serious brain injuries?
deceleration injury.
why is deceleration so devastating?
brain is made up of discrete regions of differing density. things move at different rates, tear at junctions.
subdural hematoma: what can cause the tearing of the bridging vein?
rotational injury. even if you take out the blood, there may still be damage due to the rotation.
what is evidence that there may be rotational damage in addition to a subdural hematoma?
the shift of the midline may be bigger than the space taken up by the hematoma. due to rotational damage.
acute subdural hematoma: mortality?
50-70%
chronic subdural hematoma: occurs in what group?
elderly. they have atrophied brains, allows more space for blood to collect.
also, bridging veins are stretched because of atrophied brain. easier to damage.
chronic subdural hematoma in an elderly person: presentation?
may takes weeks for symptoms to appear: confusion, headache, focal deficit
acute v chronic hematoma: appearance on imaging?
acute: clot is HYPER dense
chronic: blood products break down, become the same density as CSF.
what was the belief about the connection between ICP and prognosis?
belief that if you treated high ICP and normalized it, that prognosis is better.
Initial efforts at control of ICP were largely directed at controlling what?
cerebral blood volume
what two impt things are in the numerator of Pouseille’s Law (generally)?
radius and cerebral perfusion pressure
if body maintains a constant flow (Q), if you increase pressure, what should happen with radius?
decrease.
why is having a decreased radius of cerebral vasculature helpful?
lowers total area, lowers ICP.
what should the cerebral perfusion pressure be?
disagreement about this: <70? 50?
note: there is not clear consensus on whether the primary goal should be control of ICP or CPP.
good to know.