Neurologic Emergencis Flashcards
Cerebral infarction risk factors
Advanced age Hypertension DM High cholesterol Tobacco use Atrial fib
What is the most common cause of thrombotic occlusion?
Atherosclerosis
Happens most commonly at the carotid bifurcation or in the vertebrobasilar system
What % of strokes are ischemic?
80%
What vessel is frequently found to have the greatest degree of compromise in cerebral infarction?
Middle cerebral artery
Morbidity and mortality are higher for what kind of stroke?
Hemorrhagic
Why are transient ischemic attacks (TIAs) important to recognize?
May be clinical markers for an increased risk of subsequent cerebral infarction
Cause of hemorrhagic stroke
Intracerebral hemorrhage
subarachnoid hemorrhage
subdural hemorrhage
epidural hemorrhage
What is the primary underlying cause of hemorrhagic stroke?
Hypertension
Why do cerebellar and brainstem strokes occur?
Pathology in the vertebral or basilar arteries
Ssx of cerebrellar or brainstem stroke
Gait or limb ataxia Vertigo or tinnitus Nausea and vomiting Hemiparesis or quadriparesis Eye mvmt abnormalities resulting in diplopia or nystagmus Oropharyngeal weakness or dysphagia
Berry aneurysm
A thin wall out-pouching from an area on the circle of Willis
What is the most frequent cause of clinically significant subarachnoid hemorrhage?
Rupture of a berry (saccular) aneurysm
The 4 principal groups of vascular malformations
- arteriovenous malformations
- cavernous hemangiomas
- venous hemangiomas
- capillary telangiectasias
Acute hypertensive encephalopathy
A syndrome arising in a hypertensive patient characterized by diffuse cerebral dysfunction including: H/As, confusion, vomiting, convulsions and possible coma
Concussion characteristic neurologic picture
Instantenous onset of transient neurologic dysfunction including loss of consciousness, temporary respiratory arrest and loss of reflexes
Anisocoria
Unequal pupil size
Can be a sign of brain injury more serious than concussion
Battle’s sign
Mastoid ecchymosis
Suspect basilar skull fracture!!
Raccoon’s eyes
Bilateral periorbital ecchymosis
If the pt is unconscious or has a hx or head trauama, suspect basilar skull fracture!
Basal skull fractures
Special category of linear fractures extending through the petrus portion of hte temporal bone that leak spinal fluid from an ear
Could be hearing loss, instability of gait, vertigo
Displaced skull fracture
Fracture in which bone is displaced into the cranial cavity by a distance greater than the thickness of the bone
What vessels are vulnerable to injury esp with skull fractures?
Vessels within the dura
Most importantly the middle meningeal artery
Subdural hematoma
Damage to bridging veins between the brain and the superior sagittal sinus leads to accumulation of blood between the dura and the arachnoid
Meningitis
Acute inflammation of the meninges
Most common sx of meningitis
Fever
H/A
Nuchal rigidity
+ Kernig’s or Brudzinski sign
Positive Brudzinski Sign
Flexion of the neck causes involuntary flexion of the knee and hip
what bacteria that can cause bacterial meningitis can cause a petechial rash?
Neisseria meningitidis
Most common organisms in bacterial meningitis in premature babies and newborns up to 3 months of age
Group B streptococci
Escherichia coli
Listeria monocytogenes
Most common organisms that cause meningitis in older children
Neisseria meningitidis
Streptococcus pneumoniae
H Influenza type B (in countries wiht no vaccine)
80% of adult bacterial meningitis cases are caused by…
Neisseria meningitidis
Strep pneumoniae
Viruses that cause viral meningitis
Enteroviruses Herpes simplex Varicella zoster Mumps Measles West nile HIV
Causes of non-infectious meningitis
Spread of cancer to the meninges
Certain drugs –> non-sterioidal anti-inflmmatory, antibiotics, intravenous immunoglobulins
Inflammatory conditions –> Sarcoidosis, SLE
