Stroke Active Learning - J.Prun

Question 1

Describe stroke types & causes
Relate symptoms to anatomy
Describe initial stroke evaluation & management
Relate mechanisms of stroke to strategies for stoke prevention
Describe the mechanism of action, role, and contraindications of the use of TPA in stroke

Answer 1

1

Question 2

Definition of stroke?

Answer 2

Sudden onset of focal CNS deficit due to vascular cause!

Question 3

What do TIA and TSI stand for?

Answer 3

Transient Symptoms of Infarction

Transient Ischemic Attack

Question 4

What are the differences between TSI and TIA?

Answer 4

The key distinction of TIA is that it does not have permanent tissue damage.

TSI basically has resolved symptoms as well, but you still see evidence of the infarct on imaging

Question 5

Why is it important to be able to identify the difference between TIAs and TSIs?

Answer 5

TSI is associated with increased risk for stroke in following weeks. TIA not so much

Question 6

Difference between hemoorhagic and ischemic stroke?

Answer 6

Blood leaks into brain tissue vs blood clot stops blood supply

Question 7

Stroke can be further divided into large and small vessel disease. Describe the broad main points of both kinds:

Answer 7

Large vessel:
-Can affect anterior and posterior circulation
ANT
-Common carotid - middle/anterior cerebral arteries
POST
-Vertebral - basilar -posterior cerebral artery

Small Vessel

• Involves penetrating arteries of the brain
• Lacunar
• Hypertension induces endothelial damage and bleeding
• Endothelial damage can also form clots - occlude

Question 8

How will an intracerebral hemorrhage at the putamen present?

Answer 8

Contralateral hemiparesis, gaze paresis, aphasia

Question 9

How will an intracerebral hemorrhage at the thalamus present?

Answer 9

Contralateral hemianesthesia

Question 10

What are the similarities between Intracerebral and subarachnoid hemorrhages?

Answer 10

They are both bleeding into brain tissue

You can identify both on a Non-contrast CT

Question 11

How do you manage intracranial hemorrhage?

Answer 11

Stop anticoagulants

Surgically remove clots

Question 12

General cause of subarachnoid hemorrhage?

Answer 12

Trauma and shearing forces which tears vessels in the subarachnoid space, normally filled with CSF

Question 13

Most common non-trauamatic cause of subarachnoid hemorrhage?

Answer 13

Rupture of intracranial anyeurisms

Question 14

Subarachnoid hemorrhage management?

Answer 14

Nimodopine - a Ca channel blocker is thought to improve outcomes somewhat

For anyeurisms - clamps or coils used

Question 15

Some differences between Intracerebral and subarahnoid hemorrhages?

Answer 15

Intracerebral

• Blood shows up in different areas wherever its bleeding
• focal neural deficits
• pain free
• no drugs to treat

Subarachnoid

• Anyeurisms
• Treat with Nimodipine
• Diffuse in CSF and subarachnoid
• THUNDERCLAP headache

Question 16

What deficits will be produced by an anterior cerebral artery stroke?

Answer 16

• more likely to affect the legs
• associated with frontal lobe problems (personality)
• blindness in one eye

(one of the 1st branches off the ICA is the ophthalmic artery. Occlusion of the ophthalmic artery can cause amaurosis fugax or blindness in one eye. )

Question 17

What deficits will be produced by a middle cerebral artery stroke?

Answer 17

• Face & arms are affected more than legs
• Patients often experience a homonymous hemianopsia
• Dominant hemisphere usually causes aphasia (language probs)
• Nondominant hemisphere causes contralateral hemineglect

Question 18

What deficits will be produced by a vertebral artery stroke?

Answer 18

Affect: inferior cerebellum and lateral medulla

Cerebellar strokes cause symptoms of vertigo, blurred vision, vomiting, nystagmus, ataxia, & postural instability.

Lateral medulla = Wallenberg syndrome
-crossed symptoms, like:
numbness on the right side of the face and left side of the body due to damage to the cranial nerves on the ipsilateral side and damage to the sensory fibers above where they cross from the contralateral side

Question 19

What deficits will be produced by a basilar artery stroke?

Answer 19

The basilar artery supplies rostral brainstem & occipital lobes

-Causes cranial nerve palsies, which may result in gaze problems, hemianopsia, & miosis.

• Bigger occlusions can cause more severe deficits and damage the reticular activating system leading to altered levels of consciousness
• mortality rates as high as 90%

Question 20

What deficits will be produced by a posterior cerebral artery stroke?

Answer 20

The posterior cerebral artery (PCA) supplies the occipital lobes.

• present with a homonymous hemianopsia of the contralateral vision field.
• PCA infarcts of the nondominant hemisphere may result in neglect of the affected vision field.
• stroke may have less obvious signs for clinicians

Question 21

What deficits will be produced by a lenticulostriate artery stroke?

Answer 21

The lenticulostriate arteries branch off the middle cerebral artery to deep structures of the brain
-stroke hallmark is a lack of cortical signs

Infarction of the posterior limb of internal capsule will result in pure motor stroke
-patients experience hemiparesis of the legs, arms & face on one side due to disruption of the descending corticospinal and corticobulbar tracts

Infarction of the lateral thalamus results in a pure sensory stroke
-patients experience numbness of the legs, arms & face on the contralateral side of the body.

Question 22

What is the timeline for using fibrinoltic therapy on a stroke patient?

Answer 22

Must have had stroke less than 4.5 hours previous

Question 23

Why on earth would you do a rectal exam on a stroke patient?

Answer 23

If you are thinking about giving a TPA (Tissue Plasminogen Activator) then you need to make sure that they don’t have any sort of occult GI bleeds that could be complicated with therapy…

Question 24

If a patient has stroke symptoms related to anterior circulation, what is a good specialized test to check that out?

Answer 24

carotid doppler ultrasound

-can detect underlying carotid artery stenosis

Question 25

If you have a teenage come in with stroke, what is the #1 thing you think may have created the complication?

Answer 25

Drug abuse

Question 26

Patients that present with stroke and VERY high blood pressure. What do you do?

Answer 26

Antihypertensives withheld unless they exceed 220/120. - no shown benefits - risk that lowering blood pressure will decrease cerebral perfusion and worsen brain ischemia.

Question 27

Why is a Patent Foramen Ovale (PFO) a risk factor for unexplained strokes?

Answer 27

Embolism is actually able to pass from the venous system's right atrium into the arterial system of the left atrium. This allows the clot into the aterial circulation where it can cause an infarct!

Question 28

How clogged do your arteries have to be in order to consider carotid endarectomy?

Answer 28

Over 50%