lecture 3: ischemic stroke

Question 1

two main types of strokes

Answer 1

ischemic
hemorrhagic

Question 2

what is ischemic stroke

Answer 2

a blockage cuts off the blood supply to part of your brain.

Question 3

what is hemorrhagic stroke

Answer 3

bleeding into the brain by rupture of a blood vessel

Question 4

what is a stroke ?

Answer 4

= reduced blood flow to a certain
area of the brain
= caused by blockage of blood vessel
= reduces the blood flow to the affected area of the
brain
= leads to ischemia (reduced oxygen
supply)
= death of the brain cells that are affected

Question 5

when we suspect someone has stroke, what scan should we carry out immediately?

Answer 5

CTA - CT angiography

Question 6

what would you see in a pp that has occlusion of the right middle cerebral artery ?

Answer 6

left sided weakness
facial droop
motor aphasia
loss of ability to speak and express speech
sensory loss of left side of face
decreased level of consciousness
homonymous hemianopia

Question 7

lab tests ?

Answer 7

INR
glucose levels

creatine levels

Question 8

tx

Answer 8

MECHANICAL THROMBECTOMY
WITH ASPIRATION CATHETER
AND STENT-RETRIEVER

Question 9

what is mechanical thrombectomy WITH ASPIRATION CATHETER
AND STENT-RETRIEVER

Answer 9

• removal of blood clot from blood vessel
• aspiration catheters are used mostly in pp’s with MI to help remove clots ( most pp’s may present with atrial fibrillation)
• a stent helps bv’s heal by enlarging a specific area where the plaque build-up is located

Question 10

after operation, you do what

Answer 10

a post operative ct scan
observe pp’s behaviour
observed improvement neurologically
pp can be discharged

Question 11

case 1:
66 woman
right hemiplegia
gaze deviation
FAST positive
airway compromised
LAMS = 4 ( on a scale from 0-5)

Answer 11

1. determine LKW and severity of stroke = if LKW was <24hrs, then take pp to comprehensive stroke centre if journery under 30mins
2. adminiter t-pa = helps dissolve clot
3. contrast dye via femoral artery to see where occlusion is

Question 12

acute stroke algorithm:
first thing to do ?

Answer 12

activate acute stroke team
non contrast ct scan (negative for hemorrhage)

Question 13

if there’s a large hypodensity on ct or infarcts on mri, what do we do

Answer 13

• conservative therapy
• stroke unit admission
• urgent angiography

Question 14

if pp had acute stoke but is stable and it was mild with non-disabling deficits, what do we do

Answer 14

• conservative therapy
• stroke unit admission
• urgent angiography

Question 15

if pp’s NIHSS (stroke score 0-20) is above 4 (from 4, its moderate stroke)
OR,
isolated aphasia(speech), hemianopsia (visual), or any disabling deficit
what do we try to figure out

Answer 15

LKW

Question 16

if LKW is under 4.5 hours then what is eligable

Answer 16

t-pa

Question 17

if LKW is over 4.5 hours what is not eligible

Answer 17

tpa

Question 18

if LKW is under 4.5 hrs, t-pa is administered and what may be observed

Answer 18

behavioural or neurological improvement

Question 19

if LKW is over 4.5 hours t-pa is not eligible, then what do we do

Answer 19

non-invasive angiography

Question 20

once an non-invasive angiography is done (in case of the Lkw being over 4.5 hrs so we could not administer tpa to help dissolve the clot) - if a large vessel occlusion is observed, what do we consider

Answer 20

endovascular therapy

• then stroke unit admission

Question 21

case 2:
50
man
hypertension
smoker
found by 9am knocking into things
right sided hemiplegia and aphasia
Lkw = midnight (12am)
wife called 911

Answer 21

diagnosis = WAKE UP STROKE; this means we do not know the exact onset (Lkw) as the pp experienced their symptoms upon awakening.

1. head ct
2. nihss stroke score
3. contrast dye via femoral artery

= immediate emergent non-invasive angiography = large vessel occlusion? consider endovascular therapy

pp’s with wake up stroke may benefit from thrombectomy ( surgery to remove a blood clot from a blood vessel) if they have good collaterals

Question 22

” endovascular therapy” intervention means ?

Answer 22

1. Stent Retrievers - tiny mesh tubes that grab and extract blood clots. This is placed in the occluded vessel through a catheter placed in the groin

Aspiration System - used to remove obstruction

“Solumbra” - the combination of a stent retriever and aspiration system

Trevumbra

= all of which are minimally invasive and help remove the obstruction causing lack of blood flow to the brain

Question 23

case 2 continued: wake up stroke: remember the pp has hypertension, is a smoker and right sided hemiplegia and aphasia ; this is what was seen on the angiography

Answer 23

complete occlusion of left ICA and MCA

Question 24

ACUTE ISCHEMIC STROKE TX ONLY:

Answer 24

1. iv t-pa = helps dissolve clots = must be administred within 0-4.5 hours from symptom onset
2. mechanical thrombectomy =

use of stent retriever ( tiny mesh tubes that grab and extract blood clots. This is placed in the occluded vessel through a catheter placed in the groin)

mechanical thrombectomy time window is up to 6 hours from
symptom onset*

If the patient fails IV t-PA or is ineligible for IV t-PA , they may be eligible for mechanical thrombectomy*

Question 25

timing

Answer 25

IV TPA within 4.5hrs of onset

Endovascular therapy generally within 6hrs of onset

Question 26

deficit severity

Answer 26

NIHSS generally at least 6 or higher

Question 27

IMAGING BASED SELECTION

Answer 27

CTA or MRA, CT, MRI