Neurologic Emergencies Flashcards
1. Describe assessments specific to the care of a neurologic patient in an emergency department. 2. State presenting symptoms of common neurologic conditions treated in an emergency department. 3. Describe management of patients with spinal cord injuries. 4. Differentiate complete and incomplete spinal cord injuries.
define neuron
building block of nervous system
types of neurotransmitters
excitatory
inhibitory
excitatory neurotransmitters
norepi
acetylcholine
inhibitory neurotransmitters
serotonin
dopamine
GABA
what protects the brain?
hair scalp skull meninges CSF
mengines overview
think PAD:
- pia mater
- arachnoid mater
- dura mater
components of the cerebrum
frontal
temporal
parietal
occipital
frontal lobe
speech on L side (90%)
- Broca area
- Wernicke area
judgement, affect, coordinates voluntary motor movements, social behavior
AKA “Mother”
Broca area
production of speech
aka “broken words”
Wernicke area
comprehension of speech
aka “What?”
temporal lobe
memory
hearing
emotions
dominant-hemisphere speech
parietal lobe
sensory interpretation
occipital lobe
vision
components of brainstem
midbrain
pons
medulla
importance of brainstem
houses all vital centers:
- cardiac
- respiratory
- vasomotor
- reticular activating system (RAS)
cerebral blood flow
cerebral vessels autoregulate to maintain adequate blood flow based
MAP - ICP = CPP
maintain CPP > 60 mmHg to ensure auroregulation and adequate perfusion
intracranial pressure
Monro-Kellie doctrine
fixed cranial vault
Monro-Kellie doctrine
to maintain constant intracranial volume, an increase in one element must be accompanied by corresponding decrease in another element (blood, CSF, brain)
fixed cranial vault
brain tissue: 80%
CSF: 10%
blood: 10%
myelin sheath
surrounds axon
allows nervous or chemical transmission quickly down neuron
damage such as MS
pia mater
very thin layer that adheres to brain
arachnoid mater
very thin vascular layer like spider-web
where is CSF?
between pia and arachnoid mater
dura mater
tough, fibrous membrane
cerebellum
posture
coordination
muscle memory
reticular activating system (RAS)
determines level of alertness and attention
how does motor and sensory information travel?
crosses at level of brainstem
aka L side injury affects R side
primary determinant of cerebral blood flow autoregulation
CO2
- high levels causes vasodilation
- lower levels cause vasoconstriction
normal MAP and normal ICP
MAP: 100
ICP: 10
AVPU
alert
responds to voie
responds to pain
unresponsive
Glasgow Coma Scale
best eye opening
best verbal response
best motor response
eye opening in GCS
4 spontaneous
3 verbal
2 pain
1 none
verbal response in GCS
5 oriented 4 confused 3 inappropriate words 2 incomprehensible sounds 1 none/intubated
motor response in GCS
6 obeys 5 localizes pain 4 withdraws to pain 3 flexes to pain 2 extends to pain 1 none
FOUR score overview
to assess neuro status
includes resp pattern
useful for ventilated patients
out of 16
components of FOUR score
eye movement
motor response
brainstem reflex
respiratory quality
purpose of NIH stroke scale
to determine if tPA is an option and to predict outcomes
components of NIH stroke scale
LOC best gaze visual fields facial palsy motor ataxia sensory language/dysarthria extinction/inattention
blood glucose in neuro assessment
hypoglycemia can mimic sx of neuro emergency
pupil assessment
test both direct and consensual response
causes of pinpoint pupils
opioids
organophosphates
uveitis
causes of unilateral pupil dilation
pressure on cranial nerve III
causes of bilateral, fixed pupils
impending tentorial herniation
causes of nystagmus
drugs
MS
tumor
causes of ovioid pupils
glaucoma
decorticate posturing
abnormal flexion
lesion in cerebrum
decerebrate posturing
abnormal extension
lesion in brainstem
otorrhea/rhinorrhea in neuro assessment
clear drainage from ear or nose may indicate CSF lea
check for glucose
Babinski reflex
+ result is dorsiflexion of great toe w/ fanning of remaining toes in response to stroking lateral aspect of foot
Brudzinski sign
sx of meningitis
flexion of hips and knees in response to flexion of neck
Kernig sign
sx meningitis
inability to extend knee in response to hip flexion
doll’s eyes
+ test in comatose patient will have eyes move in opposite direction when head is rotated to one side, indicating intact brainstem
CN I
olfactory
smell
CN II
optic
vision
CN III
oculomotor
pupil size, extraocular movement
CN IV
trochlear
extraocular movement
CN V
trigeminal
facial sensation, jaw movement
CN VI
abducens
extraocular movement
CN VII
facial
facial movement
CN VIII
vestibulochoclear/acoustic
hearing
CN IX
glossopharyngeal
swallowing
CN X
vagus
gag
CN XI
accessory (spinal)
shoulder shrug
CN XII
hypoglossal
tongue movement
mnemonic for names of cranial nerves
Only - Olfactory Once - Optic One - Oculomotor Takes - Trochlear The - Trigeminal Anatomy - Abducens Final - Facial Very - Vestibulochoclear/acoustic Good - Glossopharyngeal Vacations - Vagus Are - Accessory (spinal) Had - Hypoglossal
mnemonic for functions of cranial nerves
some say marry money, but my brother says bad business marrying money
S - sensory
M - motor
B - both
function of CN II, III, IV, VI
sight, pupils, eye movements
function of CN IX, X, XII
gag, speech, swallow
function of V, VII
raise eyebrows, facial sensation
function of XI
shoulder shrug
HA sx indicating serious underlying cause
sudden onset peak intensity in min no hx of similar HAs concurrent infection w/w/o fever altered LOC > 50 yo HA with exertion stiff neck paiplledema toxic appearing
two types of HAs
primary
secondary
define primary HA
no identifiable organic cause
types of primary HAs
migraine
cluster
migraine HAs
w/w/o aura trigger unilateral photo, phonophobia N/V
cluster HAs
episodic excruciating unilateral burning, severe, sharp pain (periorbital, temporal) <1 hr, 1-8x/day unilateral tearing, nasal congestion flushing more in men
causes of secondary HAs
tumor
aneurysm
meningitis
assessing HAs
CBC, ESR
CT/MRI
lumbar puncture
HA interventions
analgesics (NSAIDs, opioids) antiemetics antihistamines vasoconstrictors anticonvulsants education
define stroke
rapid or gradual neurologic deterioration that affects a known vascular territory, resulting in focal deficits
types of stroke
ischemic (80%)
hemorrhagic (10%)
causes of ischemic strokes
atherosclerosis
emboli
types of hemorrhagic strokes
intracerebral
subarachnoid
define transient ischemic attack
brief episode of neurologic dysfxn d/t focal cerebral ischemia not associated with infarction
concerns with TIAs
not benign
10-15% have stroke w/in 3 mo
of those, 50% w/in 48 hrs
sx TIA
sudden onset unilateral weakness/paralysis abnormal sensation altered speech facial weakness AMS visual changes dizziness
conditions mistaken for stroke
hypoglycemia migraines sepsis Bell's palsy peripheral neuropathy benign positional vertigo conversion disorder seizures
Bell’s Palsy overview
occurs after infection
unable to close eye
weak blink
facial droop
assessing stroke
ABC glucose labs last known normal CT, CTa
stroke time goals
last known normal, sx onset
door to physician: 10 min
door to CT: 45 min
door to needle: 60 min
door to floor: 3 hrs
criteria for tPA
institutional criteria negative head CT NIH 4-20 or 4 with visual/speech sx door to needle 60 min sx onset <3-4.5 hrs ago
intervene for ischemic stroke
BP < 185/110
- labetalol
- nicardipine
tPA
administering tPA
0.9 mg/kg (max 90mg) bolus 10% over 1 min, remainder over 1 hr BP < 185/110 VS, neuro q 15 min for 1 hr monitor for bleeding, angioedema
sx intracerebral hemorrhage
focal deficits
rapid deterioration
intervene intracerebral hemorrhage
ABCs
BP
limit bleeding
BP in intracerebral hemorrhage
can lower systolic to 140 aggressively
limiting bleeding in intracerebral hemorrhage
vit. K
fresh frozen plasma
frequent reA
define subarachnoid hemorrhage
bleeding into subarachnoid space
usually d/t aneurysm or AV malformation
sx subarachnoid hemorrhage
"worse HA of life" altered LOC N/V focal deficits photophobia nuchal rigidity
intervene subarachnoid hemorrhage
ABCs
BP
surgery
SBP @ 160
define seizure
sudden, excessive, abnormal electrical discharge
sx seizure
involuntary movement
altered sensation/behavior
possible altered LOC
causes of seizures
pH, electrolytes alcohol withdrawal, drugs hypoglycemia, hypoxia fever, meningitis trauma, tumor stress, stroke vascular insufficiency
classifications of seizures
partial general simple complex convulsive nonconvulsive
define status epilepticus
series of seizures or one continuous seizure lasting greater than 5 minutes that is unresponsive to traditional treatments
concerning sequelae of status epilepticus
hypoxia
acidosis
hypoglycemia
intervene for status epilepticus
ABCs
cause
meds for active seizures
lorazepam
phenytoin
meds to prevent seizures
phenytoin
fosphenytoin
thiamine
antipyretics
define meningitis
acute inflammation of meninges
bacterial causes of meningitis
meningococcus
strep. pneumoniae
group B beta hemolytic streptococci
viral causes of meningitis
enteroviruses
sx meningitis
AMS
fever, nuchal rigidity
nonblanching petechial rash
rash in meningitis
usually on torso and legs
assume bacterial, isolate
septic work up
abx ASAP
intervene meningitis
droplet
abx ASAP
peds specific sx for meningitis
poor feeding irritable, high-pitched cry lethargy bulging fontanels seizures
purpose of ventricular shunt
divert CSF from lateral ventricle to low-pressure area such as peritoneum, atriumm
complications of ventricular shunt
infection
obstruction
mechanical failure
infection of ventricular shunt
sepsis
meningitis
ventriculitis
obstruction of ventricular shunt
plugging by choroid plexus
blood clot
debris
mechanical failure of ventricular shunt
detachment
malposition
growth of pediatric patient
define Guillain-Barre
acute peripheral neuropathy causing ascending weakness
autoimmune disease causing damage to myelin sheath
sx Guillain-Barre
extremity tingling
loss of deep tendon reflexes
ascending symmetric paralysis
Guillain-Barre interventions
25% require ventilation
supportive care
define multiple sclerosis
autoimmune disease that attacks CNS and demyelinates axon
sx multiple sclerosis
changes in sensation
complete/partial vision loss, double vision
weakness
unsteady gait, balance
intervene multiple sclerosis
steroids
immunosuppressants
antineoplastics
define myasthenia gravis
autoimmune disease of neuromuscular junction causing decreased receptor sites for acetylcholine binding
sx myasthenia gravis
slowed innervation - muscle fatigue
weak eye muscles - ptosis
weak pharyngeal muscles - dysphagia
weak resp muscles - resp paralysis
define Parkinson’s disease
chronic degenerative disease affecting dopamine pathway
less dopamine produced
loss of modulating effect of dopamine on voluntary motor pathways
sx Parkinson’s disease
tremor at rest rigidity resistance to passive movement cogwheel extremity movement facial "mask"
intervene Parkinson’s
carbidopa/levodopa
sx management
define ALS
genetic mutation causing progressive loss of voluntary muscle control
sx ALS
limb weakness gait/grip strength loss dysarthria dysphagia dyspnea resp insufficiency
does not affect personality, intelligence, eye function
define Alzheimer’s/dementia
loss of global cognitive ability for 6 mo or more
sx Alzheimer’s/dementia
changes or loss in:
- memory
- attention
- language
- problem solving
differential diagnoses with Alzheimer’s/dementia
delirium
encephalopathy
depression
causes of primary traumatic brain injury
direct neuronal/glial disruption compression stretching shearing brain lacerations
causes of secondary traumatic brain injury
cellular changes hypoxia hypercarbia cerebral edema hypotension
mild TBI overview
GCS 13-15
LOC < 30 min
no deficits
no changes on imaging
moderate TBI overview
GCS 9-12
+ LOC
focal deficits
pathology on imaging
severe TBI overview
GCS < 8
significant LOC
abnormal posturing, pupils
pathology on imaging
early sx of increased ICP
altered LOC HA N/V amnesia of injury restlessness, drowsiness changes in speech loss of judgement
late signs of increased ICP
unresponsive to verbal/pain
abnormal motor posturing
dilated/nonreactive pupils
Cushing triad
cingulate hernia
midline shift
central hernia
uniform increase in ICP
pushes on ventricles
both hemispheres through tentorium
uncal hernia
pressure on CN III
ipsilateral/same side pupil dilation
contralateral muscle paresis
cerebellotonsillar hernia
cerebellum pushes toward tentorium
upward hernia
increased pressure in posterior fossa
tissues moves upward
transcalvarial
pushes through skull fracture site
hernia interventions
airway prevent: -hypoxia -hypotension -hyperventilation -hyperglycemia -hypo, hyperthermia
surgical decompression
definitive increased ICP treatment
sedation, paralysis elevate HOB mannitol ICP monitoring CSF drainage
define diffuse axonal injury
significant deterioration of neurologic fxn with no focal lesions
characterized by microscopic damage to axons
sx diffuse axonal injury
immediate LOC
abnormal posturing
sx basilar skull fractures
HA
altered LOC
sx anterior fossa basilar skull fractures
periorbital ecchymosis (raccoon eyes)
rhinorrhea
sx middle fossa basilar skull fractures
mastoid ecchymosis (Battle’s sign)
otorhea
define epidural hematoma
collection of blood between skull and dura
secondary to temporal impact with laceration of middle meningeal artery
sx epidural hematoma
brief LOC
lucid interval
then 2nd LOC
contralateral hemiparesis
ipsilateral pupillary dilation
define subdural hematoma
collection of blood between dura and subarachnoid layer
MOI in subdural hematoma
acceleration/deceleration
tear of bridging veins
risk factors for subdural hematoma
older
chronic alcohol use
anticoags
types of subdural hematomas
acute - 48 hrs
subacute - 2-14 days
chronic - > 2 weeks
sx acute subdural hematoma
HA
focal deficits
sx subacute subdural hematoma
confusion
ataxia
assessing spinal trauma
motor function -tone -strength sensory function dermatomes
assessing tone in spinal trauma
flaccid spastic rigid hypertonia hypotonia
assessing strength in spinal trauma
0 no movement 1 trace movement 2 muscle movement not against gravity 3 muscle movement not against resistance 4 weak muscle movement against resistance 5 normal
assessing sensory function in spinal trauma
sharp/dull
light touch
absent
dermatomes
8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal
vertebrae and anatomical landmarks
C3 - diaphragm C6 - deltoid T4 - nipple line T10 - umbilicus T12 - symphysis pubis L4 - toe L5 - perianal area
define spinal cord injury (general)
bruising or tearing of cord from trauma, fracture/dislocation of vertebrae, MVC, falls, sports, violence
types of spinal cord injuries
hyperflexion hyperextension axial load/compression rotation penetration
SCIWORA
spinal cord injury without radiographic abnormality
more in children d/t more flexible bones
define incomplete spinal injury
some degree of motor fxn or sensation below level of injury
cause of central cord syndrome
hyperextension
falls in older adult
sx central cord syndrome
upper extremities more affected than lower extremities
sensory deficit varies
causes of anterior cord syndrome
hyperflexion
sx anterior cord syndrome
paralysis below level of injury
loss of pain and temp sensation
intact touch and proprioception
corticospinal tract
descending motor pathways from cortex to periphery
cross at brainstem - contralateral injury
dorsal column
position sense
cross at brainstem but with ipsilateral injury
spinthothalmic tract
from periphery to cortex
cross at/near level of injury
contralateral injury
Brown-Sequard syndrome
hemisection of cord (knife, gun)
sx Brown-Sequard syndrome
ipsilateral paralysis
ipsilateral los of light touch, proprioception
contralateral loss of pain, temp
define complete spinal cord injury
loss of all motor/sensory fxn and reflexes below level of injury
bilateral external rotation of legs at hips
loss of voluntary bowel/bladder fxn
priapism
spinal shock overview
injury at any level
loss of motion/sensation below level of injury
sx spinal shock overeview
flaccid paralysis
loss of reflexes
bowel/bladder dysfxn
neurogenic shock overview
injury at T6 or above
loss of sympathetic innervation and vasomotor tone
sx neurogenic shock
hypotension
bradycardia
warm, flushed skin
intervene for complete spinal cord injury
ABCs spinal motion restriction normothermia emotional support highdose steroids?
define autonomic dysreflexia
after spinal shock resolved,
strong sensory input from below level of injury causes massive sympathetic discharge
T6 or above
causes of autonomic dysreflexia
over-distended bladder
bowel distention/impaction
skin breakdown/pressure
intra-abdominal pathology
sx autonomic dysreflexia
HA HTN nasal congestion flushed head and neck pupil constriction sweating
intervene autonomic dysreflexia
treat cause and HTN
define cauda equina syndrome
“horsetail” bundle of nerves at base of spinal cord is compressed, trauma, or damaged
sx cauda equina syndrome
weakness, paralysis sensory impairment pain saddle anesthesia bowel/bladder sx
assessing cauda equina syndrome
emergent CT/MRI
