TBI Flashcards
define TBI
disruption in the normal function of the brain that can be caused by a bump, blow, or jolt to the head or a penetrating head injury
how to assess severity of a TBI
glasgow coma score
4 points of eye response in CGS
No eye opening
Eye opening to pain
Eye opening to verbal command
Eyes open spontaneously
5 points of verbal response in CGS
no response
incomprehensible sounds
inappropriate words
confused
oriented
6 points of motor response in CGS
no response
extension to pain
flexion to pain
withdrawal from pain
localizing to pain
obeys commands
what CGS is mild TBI
13-15
what CGS is severe TBI
3-8
most common cause of TBI is
falls
are M or F more likely to experience TBI
M
describe mechanisms of primary injury in TBI
contact: impact or penetration
sudden acceleration/ decceleration
3 types of injury in TBI
focal
diffuse
mixed
what is secondary injury
brain cells continue to die after primary injury in min-days following
Intracranial hemorrhage, subarachnoid hemorrhage, subdural hematoma leads to
hydrocephalus and vasospasm
systemic hypotension results in
decreased perfusion
impaired cerebral vascular autoregulation results in
↑BP = ↑ CBF, ↓BP = no perfusion, lacks regular regulation even when BP fluctuates
in TBI there is increased metabolic demand due to
seizures, fever, agitation
Free radicals, excitotoxicity, disruption of BBB → _________ → ______
cerebral edema
↑ICP
5 predictors of poor outcome from TBI
older age
lower CGS score
abnormal pupillary response
systemic hypotension
abnormalities on CT scan
target SBP in TBI
> 90
target MAP in TBI
> 60
target O2 sat and PaO2 in TBI
> 90%
60
how to improve SBP and MAP in TBI
fluid resus
vasopressors if fluids fail
how to improve O2 sat and PaO2
mechanical ventilation
surgical interventions for TBI include
external ventricular drainage
surgical evacuation of intracranial hematomas
surgical removal of foreign bodies
decompressive craniectomy
EVD is to
monitor ICP or control hydrocephalus
why is sedation done in TBI
to control agitation + pain and facilitate mech ventilation
reduce ICP, brain oxygen consumption
propofol onset/ offset time
fast both
propofol MOA
GABA-A receptor agonist
propofol properties
antiseizure
neuroprotective
propofol AEs
propofol infusion sx
hemodynamic instability
respiratory depression
anxiolytic in TBI for sedation
midazolam
which opioid is used in TBI for sedation
fentanyl
target CPP
> 60mmHg
CPP =
MAP - ICP
target ICP
<20mmHg
hyperventilation can help control _________ by _________
ICP
by causing cerebral vasoconstriction (acute drop in PaCO2 = reflex cosntriction)
T or F: hyperventilation in TBI can be used LT to control ICP
F- limits blood flow to brain necessary to heal
which hyperosmolar agents are used to decrease ICP in TBI
mannitol and hypertonic saline
mannitol SEs
hypotension, ARF
mannitol MOA
draws water out of cells
decreases blood viscosity resulting in more cerebral blood flow
hypertonic saline MOA in TBI
increases osmotic gradient to draw water out of cells to decrease ICP
in TBI DVT prophylaxis, _______ is initially used then ____ or ____ if not CI
pneumatics initially
LMWH and unfractionated heparin
infection prophylaxis in TBI is recommended for
penetrating head trauma
a phenobarb coma is done in TBI to _______ and _______
reduce ICP and brain metabolism
phenobarbital coma SEs
hypotension, decreased GI motility
in pts with medically induced hypothermia to reduce ICP, what is important to watch
drug dosing- all metabolism slows down
T or F: high dose corticosteroids is recommended for reducing ICP in TBI
F- increases mortality
