B2W3 Trans Phys Stroke Flashcards
Ischemic Stroke
When cerebral blood flow is insufficient to meet the brains metabolic demands
Causes of ischemic Stroke
Thrombosis
Embolism
Hemodynamic
Thrombosis
Intracranial Large Artery disease
Penetrating large artery disease
Embolism
Extracranial disease (artery to artery emboli or flow-limiting stenosis)
Hemodynamic
Aortic arch plaque, Afib, Valve disease, and cardiomyopathy
Law of Poiseuille
CBF = (CPP)(PiR^4)/(n)(i)
Decreasing R or radius causes ischemia from the center outward
Decrease in P or pressure causes ischemia between vascular territories, increases risk of developing infarcts
Ischemic Penumbra
Territory where dead tissue radiates outwardly within a few minutes of blockage
Surrounding area may still be viable but is stunned
Occlusion of Ophthalmic Artery
Opthalmic artery is one of the first branches off of the carotid artery
- Supplies the Central Retina Artery
- Causes Amaurosis Fugax or Transient Mono-Ocular Blindness
- Transient attack meaning symptoms resolve spontaneously
- STILL AN EMERGENCY
Occlusion of the Anterior Cerebral Artery
Branch of the internal carotid artery
- Causes weakness to the opposite foot/leg, and shoulder/arm
- Does not affect the face and hands
- Involves frontal lobe
- - Causes patient slowness
Occlusion of Middle Cerebral Artery
Other branch of internal carotid artery
- Covers more territory of the brain and more common than ACA
- Weakness/numbness in the opposite face and hands
- Further symptoms associated with location of the occlusion
MCA Occlusion Location Dependency in the Artery (Left side of brain)
1st row
- Trouble Speaking and understanding
- Blocks both offshoots of the artery
2nd Row
- Trouble Speaking
- Broca’s Aphasia
- Distal superior division
3rd Row
- Trouble understanding
- Wernicke’s Aphasia
- Distal inferior division
Broca’s Aphasia
Trouble Speaking
“Broca” “Broken” “Broken Vocal Chords
Wernicke’s Aphasia
Trouble understanding
“Wernicke’s” “Is that even english”
Lacunar Syndromes
Small Vessel Disease
Lateral Lenticulostriate Arteries
Vessels that branch from the MCA and supply the putamen, posterior limb of the internal capsule and corona radiata
Occlusion of the Vertebral Artery
Major artery of the head/neck
- Posterior Inferior Cerebellar Artery (PICA)
Occlusion of PICA
- Causes Wallenberg Syndrome
Wallenberg Syndrome
Loss of sensation in the face and limbs
Treatment for Ischemic Stroke
Increase Blood flow
Increase Blood Pressure
Increase Radius
Method to increase blood flow
remove clot via IV tPA (<3-4.5 hrs) or mechanical thrombectomy (<6 hrs from onset)
Method to increase blood pressure
Sweet Spot of BP = Systolic 140 - 180mmHg
Provide Vasopressors to augment blood flow by constricting blood vessels to increase blood pressure
Increase Radius
Angioplasty or stent
Intracerebral Hemorrhage
15% of Strokes
Atrio-Venous Malformation
2nd cause of hemorrhagic stroke
-Seen in frontal lobe
Hypertensive Hemmorhage
Hypertension is the main cause of hemorrhagic stroke
Most common location of hypertensive hemorrhagic stroke
Putamina
Hemorrhagic Intracranial Volume Equation
ABC/2
ABC indicates different slices of the brain along the Z axis and the area of blood in each is multiplied and divided by 2
Ideal BP for Hemorrhagic Stroke victims
< 160 mmHg
