neurologic emergencies and surgical intervention Flashcards
(61 cards)
1
Q
normal intracranial pressure in adults
A
- <10-15 mmHg
2
Q
intracranial components by volume percentage
A
- brain parenchyma: 80%
- CSF: 10%
- blood: 10%
3
Q
following a significant increase in ICP, brain injury can result from
A
- brainstem compression (herniation)
- reduction in CBF (cerebral blood flow)
4
Q
uncal herniation will present as
A
- CN III compression
- unilateral fixed, dilated pupil
- progressive deterioration in LOC
5
Q
papilledema is a sign of
A
- increased intracranial pressure
6
Q
Cushing’s triad is an ominous finding of elevated ICP. what does it involve?
A
- bradycardia
- respiratory depression
- hypertension
7
Q
decorticate posturing. describe it? Reflects destructive lesion in the
A
- arms flexed: hands to the body core
- lesion in the corticospinal tract from cortex to upper midbrain
8
Q
decerebrate posturing. describe it? Reflects destructive lesion in the
A
- arms extended
- corticospinal tract at level of pons or upper medulla
9
Q
describe rating scale for motor function of extremities
A
- 1/5 minimal flicker
- 2/5 movement with gravity eliminated
- 3/5 movement against gravity
- 4/5 weakness
- 5/5 complete
10
Q
managememt of elevated ICP
A
- referral to neurosurgery
- oxygenation: maintain O2 sat >90%
- control HTN/avoid hypotension: maintaine cerebral perfusion pressure > 60 mmHg
- elevate head of bed to 30 deg
- analgesia/sedation
- IV mannitol: osmotic diuresis
- mechanical ventilation to lower PaCO2
11
Q
what are the three types of skull fractures
A
- linear
- depressed
- basilar
12
Q
define linear skull fracture
A
-
single fracture that most often extends through the entire thickness of the calvarium
- majority have minimal or no clinical significance
13
Q
define depressed skull fracture
A
- segment of skull is forced below the level of adjacent skull
- may be open or closed
14
Q
depressed skull fractures often involve injury to the brain parenchyma and are associated with increased risk of
A
- infection
- seizure
- death
15
Q
define Basilar skull fracture
A
- involves at least one of the bones that comprise the base of the skull
- temporal bone, occipital bone, sphenoid bone, and/or ethmoid bone.
16
Q
Basilar skull fractures occur most commonly through which bone
A
- temporal bone
17
Q
signs of Basilar skull fracture
A
- hemotypmanum
- “raccoon eyes”
- battle sign
- CSF otorrhea or rhinorrhea
18
Q
imaging modality of choice for a suspected skull fracture
A
- noncontrast CT scan
19
Q
a brain contusion - area of bruising on the brain- is associated with localized
A
- ischemia
- edema
- mass effect
20
Q
what is a diffuse axonal injury (DAI)
A
- shearing of white matter tracts from traumatic sudden deceleration injury (blunt trauma) -> severe intracranial injury
21
Q
CT scan of diffuse axonal injury will show
A
- blurring of gray to white matter margina
- cerebral hemorrhage
- cerebral edema
22
Q
which type of intracranial hematoma is most associated with a skull fracture
A
-
epidural hematoma
- middle meningeal artery
23
Q
which intracranial hematoma is characterized by a collection of venous blood between the dura matter and the arachnoid
A
- subdural hematoma
- tearing of bridging veins
24
Q
clinical presentation
- brief LOC
- lucid interval
- rapid clinical deterioration
what will CT scan likely show
A
- epidural hemotoma
- lens-shaped
25
what will CT scan of subdural hematoma likely show
* crescent shape
26
differentiate betwen acute, subacute, and chronic subdural hematoma
* **acute**: symptoms within 24-48 hours after onset
* **subacute**: sx 3-14 days after onset
* **chronic**: sx \> 2 weeks after onset
27
nontraumatic causes of subarachnoid hemorrhage
* aneurysm
* vascular malformation
28
clinical presentation
* "worst headache of my life"
* subarachnoid hemorrhage
29
evaluation of subarachnoid hemorrhage
1. CT scan noncontrast
2. LP
1. RBC and xanthochromia
30
what is the gold standard for detecting intracranial aneurysms
* digitial subtraction angiography
31
most common cause of hemorrhagic stroke
* hypertension
32
management of hemorrhagic stroke
* neurosurgical consult
* BP control, avoid hyperglycemia
* sz prophylaxis
* hemostatic therapy
* reversal of anticoagulation
33
intraventricular hemorrhage puts a person at risk for
* hydrocephalus
34
causes of intraventricular hemorrhage
* primary uncommon
* more commonly extension of intracerebral hemorrhage or SAH
35
target BP for patient with an ischemic stroke who is not a candidate for IV thrombolysis
* no intervention unless BP
* \> 220 systolic or \> 120 diastolic
36
target BP for patient with an ischemic stroke who is a candidate for IV thrombolysis
* SBP \< 185
* DBP \< 110
37
inclusion criteria for thrombolytics
* clinical diagnosis of ischemic stroke
* onset of symptoms \< **4.5 hours** before tx
* age \> or = 18 yo
38
treatment of status epilepticus (sz lasting 5 minutes)
* Iv lorazepam (or diazepam) + IV phenytoin
39
what is indicated for all patients with a new seizure
* CT or MRI
40
patients with a new onset seizure can be discharged with outpatient f/u if
* returned to baseline
* normal CT scan
* normal lab evaluation
41
what is a jefferson fracture? cause
* most common fracture of **C1 atlas**
* caused by axial compression
42
is jefferson fracture usually associated with spinal cord damage?
* no
* because canal diameter is not compromised
43
C2 (axis) fractures, fractures of dens are usually associated with what type of injury
* forcefull flexion or extension
44
C2 (axis) fractures, fractures of dens are broken down into what types? which are stable?
* Type 1: stable
* Type 2, 3: unstable
45
What is the hangman's fracture?
* **C2** fracture involving **both pedicles**
46
hangman's fracture. type of injury associated with it?
* hyperextension with compression
* if death occurs: usually instantaneous due to spinal cord transection
47
What is a burst fracture
* direct axial load -\> fragments displacing in all directions
* spinal cord may be injured if fragments enters spinal canal
48
disk herniation diagnosed with what imaging modality
MRI
49
clinical presentation
* urinary retention
* radiculopathy
* bilateral lower extremity muscle weakness
* saddle anesthesia
* decreased anal spincter tone
cauda equina syndrome
50
evaluation of cauda equina syndrome
* emergent MRI or CT myelography
51
neurogenic shock occurs most commonly after
* cervical spine injury
52
anterior cord syndrome will present with
* **complete motor paralysis below level of lesion**
* **loss of pain and temperature sensation below level of lesion**
* retained proprioception and vibratory sensation
53
central cord syndrome will present with
* hyperextension injury of cervical spine
* **motor impairment, greatest in upper extremities**
54
brown sequard syndrome presents wtih
* spinal cord hemisection
* ipsilateral loss of motor function, proprioception and vibration sensation
* contralateral loss of pain and temperature
55
near total ventilatory muscle paralysis will occur with injury to spinal cord at what level
* above C3
56
what is the most common demyelination neuropathy
* guillain-barre syndrome
57
clinical presentation
* previous mild URI or gastroenteritis, influenza immunization or surgery
* acute onset of ascending paralysis starting distally
* weakness symmetric
* guillain-barre syndrome
58
LP in guillain-barre syndrome will show
* elevated CSF protein without pleocytosis (increase in white blood cell)
59
which type of meningitis is a neurologic emergency
* bacterial
60
patients with meningitis should be given early IV
dexamethasone
61
definitive diagnosis of brain abscess
* stereotactic (open) brain biopsy
