-
5 levels of conciousness
- alert
- lethargic
- obtunded
- stuporous
- comatose
-
lethargic
vs
obtunded
vs
stuporous
L= drowsy but verbal arousal/tactile stiumulation
O= verbal AND tactile needed response but fall asleep again easily
S= tactile stimulous needed for any response
-
noxious stimulation techniques
- sternal rub
- supraorbital pressure
- trapezius pinch
- mandibular pinch
these all illicit central stimulation
-
4 H's that need to be stabalized before we can conduct official neuro exam
- HypoTN
- Hypoxia
- Hypoglycemia
- Hypotrhermia
-
Glascow Coma Scale
and levels of brain injury
- <8 = severe
- 9-12 = moderate
- 13-15 = mild
-
periph strength scale review
0-5
- 0 no movement
- 1 flicker or trace amount
- 2 can move but not against gravity
- 3 against gravity but not resistance
- 4 weak, but can overcome gravity and mild resistance
- 5 normal
-
posturing
decoticate= hands up, damage above brain stem
decerebrate= worse, hands down, damage to brain stem
-
2nd best indicator of neuro trauma
Pupil size, reaction, and equality
-
dolls eye exam
+ finding is good, brain stem intact, eyes move opposite direction of head movement (continue to watch you)
- finding is bad, brain death possible, eyes remained fixed and do not adjust when head is moved
-
cushings triad
vital sign assessment
these indicate INC ICP
-
all drugs, sedation, bld sugar meds need to be COMPLETELY out of the system before we assess for Brain Death
-
brain death assess:
EEG
vs
Evoked potentials
EEG= look at brain waves
Evoke= give shocks to illicit response
-
Transcranial doppler
evaluation of verebral bld flow
-
caloric test
- ice h20 against tempanic membrane (ear)
- watch eye response
nl= eyes jerk toward side with h20
abnl= no response OR single eye jerks on opposide side/direction
-
apnea test
- hyperO2
- d/c vent and watch for 10 minutes
- at 10, draw ABG's and reconnect vent
- if no respers in to min AND pCO2 is >60, brain death indicated
-
3 things within the cranium and their %'s
-
normal ICP
Tx threshold
0-15 mmHg
Tx threshold >20 mmHg
-
Cerebral Perfusion Pressure
O2 delevery to the brain
- nl= 50-70, safe up to 150
- MAP - ICP = CPP
lower CPP is what we worry about
-
bld flow dec by 50% following a TBI w/n the first 24 hours
DO NOT compromise bld flow during this time
-
autoregulation w/n the brain
the cerebral bld vessels respond to changes with the cranium
-
metabolic autoreg: CO2
CO2 levels cx brain vessels to constrict/dilate which Inc or Dec ICP, affecting CPP
Hypocapnea (d/t hypervent) cx's constriction -> cerebral ischemia
Hypercapnea -> dilation -> Inc ICP
goal is 35-45 CO2 and 100% O2
-
Dec CO2
vs
Inc CO2 affects on cerebral vessels
Small CO2 = Small vessels (constriction)
Large CO2 = large vessels
-
pressure autoreg:
Inc BP -> vaso constrict (which is good if Inc ICP)
Dec BP -> dilation (good for cerebral perfusion)
-
4 primary factors that affect cerebral perfusion
- perfusion pressure
- vascular resistance
- O2 or glucose supply
- metabolic demand
-
how perfusion pressure affects CPP
-
how Vascular Resistance affects CPP
- vasospasm
- thrombosis
- Cerebral edema
- hypocapnea
-
how O2 or glucose supply affects CPP
- hypoxia
- anemia
- hypoglycemia
- CO
-
how metabloic demand affects CPP
-
Brain tissue oxygenation (PbtO2)
nl
how is balance maintained?
nl= 20-35 mmHg
- maintained by balancing:
- CPP >50
- ICP <20
-
ICP should be monitored in severe TBI's with one of these two things
- abnl CT
- OR
- nl CT with >2 risk factors
vent caths are most accurate tool
-
ventricular drains
- gold std for ICP monitoring
- invasive
- difficult to place
- draingage of CSF to Tx inc ICP
-
subarachnoid screw
- bolt placed in subarach
- lower rate of infection
- easier to place
- CSF sampling ONLY
- less accurate
-
Epidural monitoring
- low risk infect
- easy place
- NO csf access
- low accuracy
-
parenchymal monitoring
- low infect
- easy place
- NO csf access
- low accuracy, can drift d/t no recalibration option
-
ABC ICP waveforms
A.weful= large mountainous wavefore
B.ad= prominant peaks and troughs
C.ommon= small, frequent waves. What we want
-
ICP waveforms tell us about brain compliance
need to look at more than #'s and waveforms though
-
4 types of head injury forces
- acceleration (hit by moving object)
- deceleration (head is moving, falls)
- rotational (car/sports injury's)
- penetrating (gun)
-
why is the CT the gold std for dx head injuries?
Diffuse injuries do not show up on a CT but Focal injuries do.
so we rule out focal with a CT
-
primary head injuries
1-3
happen at the time of impact
- diffuse (all over, not localized)
- focal
- intracranial hemorrhages
-
types of diffuse Head Injury (HI)
- concussion
- Difues axonal Injury (DAI)
-
concussion
Sx
Tx
post-concussive syndrome
- diffuse
- mild, temporary, REVERSIBLE
- Sx= brief LOC, N/V, mem loss, confusion, dizzy, photophobia
- Tx= observation
post-conc= small % of Sx persist for up to 1 yr, usually HA, mem loss
-
Diffuse Axonal Injury (DAI)
Sx
Tx
- severe, Permanent shearing of axons :(
- dx with CT
- Sx= acute and prolonged coma, Cushings tirad, posturing, INC temp
- Tx= medical managment, control ICP and maintain CPP
-
Focal injuries
- specific area of brain
- Pupil and motor respnse for Sx
pupil is on SAME SIDE as injury
motor is on OPPOSITE SIDE of injury
-
2 types of focal injuries
-
contusion
- bruising and swelling
- coup or contracoup r/t to location of injury and/or bounce back of brain
- can be temporal or parietal
damage to midbrain, HIGH risk for epidural hematoma b/c temporal bone easily fractured
-
contusion:
Sx
Tx
sx= contalateral motor and ipsilateral pupil changes, altered LOC
Tx medical management
-
skull fractures:
linear
depressed
liner= non-displaced bone, minor
depressed= compression of brain, dura, bone missing
-
Basilar skull fractures
3 classic signs:
- raccoon's eyes = periorbital brusing
- battle's sign = mastoid bruising behind ear
- CSF leakage = usually via ear or nose (look for halo on gauze)
-
-
intracranial hemorrhage types
1-4
- epidural
- subdural
- intracerebral
- subarachnoid
-
epidural hematoma
Sx
Tx
- ARTERIAL bleed
- (E is close to A)
- b/w skull and Dura layer
- Sx= dec LOC followed by lucid period, then coma. Pupil and motor changes
- Tx= surgery. good prgonosis
-
subdural hematoma
Sx
Tx
- Venous Bld
- (S is close to V)
- b/t dura and arachnoid (below dura mater)
- Sx= gradual dec LOC, acute, subacute, or chroni onset. motor and pupil changes
- Tx= surgery. prognosis is 30-60% mortality r/t REbld risk
-
intra cerebral hematoma
sx
tx
- most often from stroke
- bld collection w/n brain tissue
- Sx= depends on location and size
- Tx= medical, always control ICP and optomize CPP
-
Subarachnoid hemat (SAH)
Sx
Dx
Tx
usually an Aneurysm
Sx= Thundering HA (worst ever!), photophobia, dec LOC, N/V, nuchal rigidity
Dx= CT, Lumbar Puncture (bld in CSF), angioplasty
Tx= clip it off
-
SAH complications
- high risk 30-60yrs
- high rik for arterial vasospasms (70% of all cases)
- peaks around 5-14 days
Sx= vision changes, hemiparesis, seizures, aphasia, dec LOC
-
vasospasm Dx and Tx
- Dx= Transcranial doppler
- Tx= Ca blocker to prevent spasms
- Double HH therapy
-
HH therapy
- HTN= induce HTN to keep vessels open with vasopressors
- =goal is >200 SBP
- Hemodilution= dec bld viscosity with IV crystaloids and colloids
- = goal is Hct of 30%
-
Secondary head injuries
6 types of changes seen in 2nd injuries
- progression of initial injury d/t cellular and toxic changes
- what happens as a result of initial injury
- hypoxia
- hypercapnea
- hypoTN
- sustained HTN
- cerebral edema (most common cx)
- herniation
-
cerebral edema
peaks 3-5 days after injury
-
herniation
uncal
vs
central
temporal lobe forced into tentorial notch (brain stem) which compresses brain stem
- un=unilateral --> focal injury
- central= Bilateral --> diffuse injury
-
Uncal herniation Sx
- fixed, blown pupil
- comatose
- loss of cranial nv and motor response
- cushings triad
- (-) dolls eyes
- C-V collapse, death
-
nsng: patient goals:
control icp
- ICP <20
- stable of inproving neurons
-
nsng: patient goals:
Perfusion/O2 delivery:
CPP
SpO2
PaO2
PaCO2
SBP
MAP
- CPP= 50-70, avoid <50
- SO2= 100%
- PO2= >100-150
- cO2= 35-45
- sbp= >90
- MAP= >70-90
-
ER phase
- ABCD's
- airway and protect spine
- OG tube ONLY (NEVER INTER THE NOSE WITH A TBI)
- ETT for GCS <9
-
ER phase: circulation
- goal is euvolemia and perfusion
- labs values similar to perfusion/o2 delivery goals
- Arterial lines are best for fluid and labs
- Central Line for CVP (6-8)
-
ER phase: Disability (D of ABCD)
thorough neuro checks and brain CT scan w/n 15 minutes to give a good baseline
-
what to do with ealy sx of herniation?
give Mannitol rescure dose of 0.25-1.0 Gm/kg
- Mannitol= osmotic diuretic (hypertonic)
- =raise tonicity of bld
- =pulls fluid into vasc space and out via kidney
-
goal of therapeutic hypothermia
- save the brain
- dec metab and O2 demand
-
nursing priorities:
cx's of inc ICP to assess for
1-7
- fever** (Tx aggressivly, even if only 1 degree over)
- hypoxemia
- agitation
- pain
- shivering
- vent asynchrony
- seizures
-
supportive nsng interventions:
positioning
space out care
bld pressure control
p= elevate HOB, head and neck alignment
s= space out b/c everything we do to them will increase ICP
bp= Tx HTN to avoid ICP
-
supportive nsng interventions:
normothermia
vent manipulation
pulmonary hygeine
n= b/c fever inc metab and oO2 demand
v= no PEEP >5, hyperO2 is OK
- Pulm= Suct. only as needed and hyperO2
- =prophylact anti-bios w/ intubation
- =early trach to dec vent days
- =early extubate does NOT inc pneumonia
-
supportive nsng interventions:
fluid managment
DVT proph
seizure control
nutrition support
- f= giuded by CVP and or of indicates of fluid status
- =ASSESS for AHD imbalance
D= SCD's, Heparin drip as proph
s= anti-convulsants
n= begin within 7 days
-
Mannitol
vs
Hypertonic saline
-
nsing priority: ICU phase:
resistant ICP: 1st tier
after we have tried other Tx
- drain CSF via vent cath
- osmotic therapy, but watch for dehydration
-
nsing priority: ICU phase:
resistant ICP: 2nd tier
- sedation with high dose barbiturates
- NO PROPOFOL in high dose or longer than 48hrs
- Hypervent for more than 24 hrs b/c dec CO2 =vasocontriction
- craniectomy
- organ donotion
-
complication of ADH imbalance
- Diabetes Insipides
- more urine out than bld level
- inc Na in bld and dec u. gravity
- SIAHD decreases UO
- dec Na in bld and inc Na in urine
-
DI Tx
SIADH Tx
D= hypotonic solutions, replace ADH with vbasopressin or DDAVP
- S= fluid restriction
- hypertonic fluids
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