Strokes: the quick and dirty

2 Major Types:

1) Ischemic: blood vessel supplying the brain is obstructed by a clot

  • Embolism
  • Thrombosis 

2) Hemorrhagic: blood vessel bursts, blood leaks throughout brain #1 Risk Factor: High blood Pressure Other Risk Factors:

  • Age
  • Sex: Male
  • Ethnicity: African Americans, Mexican Americans, Hawaiians, Asian Americans
  • Smoking
  • Fat, cholesterol-rich diet
  • Overweight
  • Pregnancy
  • Birth-control Pills
  • Smoking
  • Diabetes
  • Renal problems
  • Atrial Fibrillation

Signs of Stroke

  • Sudden, severe headache
  • High blood pressure
  • Problems with vision, reflexes, walking, movement, speaking, coherence
  • Vertigo
  • “Bruit” noise when listening to carotid arteries in neck with stethoscope

Treatment Options:

  • Ischemic: Blood thinners to reduce clots: warfarin, heparin, Coumadin
  • Hemorrhagic: surgery to remove blood in brain, repair damaged blood vessels

Academic life in emergency medicine NIH stroke scale PV card. Great resource:
http://academiclifeinem.blogspot.com/2010/02/paucis-verbis-card-nih-stroke-scale.html

Click continue reading for high yield quickhits on a few specific types of stroke and brain imaging examples Diamond_Line_Divider

stroke 1stroke 2

Location of Stroke determines range of symptoms stroke 3 Branches of Internal Carotid Artery

  • Middle cerebral artery (MCA):
    • Supplies lateral, frontal, and parietal lobes, anterior and lateral temporal lobes
    • Region supplied by MCA is large (easiest path for embolism)
    • Anterior Cerebral Artery (ACA):
      • Supplies medial frontal and parietal lobes, anterior internal capsule, and basal ganglia

Branches of Basilar Artery

  • Posterior Cerebral Artery (PCA):
    • supplies thalamus and brainstem, occipital lobes, posterior and medial temporal lobes
    • Perforating Arteries

Radiology of Stroke: Middle Cerebral Artery

  • Cerebral Angiogram: determine which vessels are obstructed or ruptured
  • Carotid Duplex Ultrasound: determine if carotid arteries are narrowed
  • CT Scan: during stroke
  • MRI: during or after stroke
  • Echocardiogram: determine atrial fibrillation causing stroke
  • Magnetic resonance angiography

—————————————————————————————–

Hypertensive hemorrhage

  • HTN is leading cause of spontaneous intraparenchmal hematoma
  • Most commonly occur in basal ganglia, thalamus, pons, and cerebellum
    • ** Most common site is putamen. Internal capsule that lies adjacent to putamen and is almost always involved à leading to hemiparesis
    • Pontine hemorrhage = present with deep coma, paraplegia that developed within a few min, pinpoint pupil, no horizontal eye movements
  • **Presentation = initially with focal symptoms, rapidly progress to signs of elevated intracranial pressure
    • Unilateral weakness, slurred speech à focal lesion in cerebral cortex
    • Global symptoms = elevated intracranial pressure
    • ** look for associated marked hypertension, rapid progression of symptoms
  •  ** noncontrast CT can help distinguish hemorrhagic from ischemic strokes

 Cerebellar hemorrhage

  • ** Symptoms = Acute onset occipital headache, repeated vomiting, gait ataxia, vertigo
    • Small hemorrhage may not manifest with any other neurological deficit
    • Large hemorrhage à 6th nerve paralysis, conjugate deviation, blepharospasm, become stuporous in a few hours
  • Cerebral hemorrhage due to excess anticoagulation
    • ** Tx = fresh frozen plasma (FFP) for rapid reversal of anticoagulation
  • Tx = immediate evacuation of the hematoma
    • If left untreated, stupor or coma may ensue due to brainstem compression
    • ** Do CT scan without  contrast in all patients with a stroke to distinguish between hemorrhagic or ischemic stroke
      • * If evidence of ischemic stroke à carotid Doppler and TEE to evaluate for possible source of embolism

Thalamic stroke (Dejerine-Roussy syndrome)

  • Stroke involving ventral postero-lateral (VPL) nucleus of the thalamus à loss of sensory information from the contralateral side of the body
  • Symptoms = contralateral hemianesthesia accompanied by transient hemiparesis, athetosis, or ballistic movements
  • ** Look for hemi-sensory loss with severe dysesthesia typical thalamic stroke

Lacunar Stroke

  • **Caused by microatheroma and liphyalinosis in small penetrating arteries of the brain
  • ** Always suspect lacunar stroke if patient presents with limited neurologic deficit
    • Typical scenarios = pure motor, pure sensor stroke, ataxic hemiparesisi, dysarthria-clumsy hand syndrome
  • ** principal cause of lacunar stroke = HTN
  • ** Most common site for a lacunar infarct is the posterior internal capsule à pure motor stroke

lacunar stroke 1

lacunar stroke 2

TIA

  • Focal neurologic symptoms lasting less than 24 hours due to cerebral ischemia
  • Head CT should be obtained in patients with stroke symptoms to distinguish ischemic vs. hemorrhagic
    • Thrombotic cause suspected à antiplatelet agent (aspiring) to prevent future events
    • Warfarin used to prevent future ischemic events due to cardiogenic emboli

Heat stroke

  • Failure of body thermoregulation upon exposure to high environmental temperatures
  • **look for very high core body temp (>105), dehydration, confusion, coma, dry flushed skin
  • Symptoms = acute confusion, hyperthermia (>105), tachycardia, persisten epistaxis after exertion under direct sunlight

References:

Stroke; Cerebrovascular disease; CVA; Cerebral infarction; Cerebral hemorrhage; Ischemic stroke; Stroke – ischemic; Cerebrovascular accident; Stroke – hemorrhagic; Last reviewed: June 24, 2011.

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001740/

 

Hemorrhagic Stroke with MCA Transformation

http://radiopaedia.org/cases/hemorrhagic-transformation-of-mca-stroke-1

 

Stroke risk factors and prevention

Stroke prevention; Preventing strokes; Last reviewed: April 30, 2011.

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004662/

Compiled by: Debi Hickman

Miss anything? Forgot to include something important? Leave a comment and help us improve our knowledge base for medical students!

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One thought on “Strokes: the quick and dirty

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