14. Stroke for local doctor

• Work up for TIA and stroke • Window time for TPA, recommendation • Treatment of hemorrhagic stroke • BP control in ICH • SAH: emergency treatment... Stroke – incidence and prevalence53

(For local doctor)

Dr Nguyen Anh Tuan

• Work up for TIA and stroke

• Window time for TPA, recommendation

• Treatment of hemorrhagic stroke

• BP control in ICH

• SAH: emergency treatment

• Cerebrovascular disease is a

major cause of mortality and

morbidity in the world

• Stroke of all types rank third as a cause of death and are surpassed only by heart disease and cancer

• Incidence: 150-200/100.000

Stroke – incidence and prevalence

531.000 new cases of stroke

and 200.000 recurrences of

stroke each year in the US

In 22 European countries with a combined population of

approximately 500 million, almost one million strokes are estimated to occur each year

Transient ischaemic attack (TIA)

• Brief episode in which neurological deficits suddenly occur, then disappear; can

persist up to 24 hours

• Temporary arterial blockage, with no

resultant brain damage

Pay Attention to these symptoms

• TIA’s should not be ignored

– More that 1/3 of people will go on to have an actual stroke

– 5% of strokes will occur within 1 month of the TIA or first stroke

– 12% will occur within 1 year

– 20% will occur within 2 years

– 25% will occur within 3 years

Stroke – aetiology

• In Vietnam, haemorrhagic stroke rate maybe higher,

up to 40% according to some recent data

• Poorly control of hypertension in community can explain the difference

ANATOMY: Blood supply to the brain

Circle of Willis

Impariment of speech, vision and co-ordination of movement

Stroke

Computed tomography (CT) and magnetic resonance imaging (MRI)

 Images taken in two-dimensional slices

 Can be reconstructed into three-dimensional images

 More available in emergency rooms

 Not reliable if done too early

Magnetic resonance imaging (MRI)

MRI scan

Cerebral infarction

 High-resolution neural imaging technique

 Different parts of the brain have different

signal intensities on T1- or T2-weighted

images

Diffusion-weighted imaging (DWI)

 Decrease in diffusion of water molecules

 Best way to image acute stroke

 Ischaemia can be visualised as early as within

30 minutes of stroke

 Relies on reduction of random diffusion (Brownian motion) of water after acute stroke

Computed tomography (CT) scan

Early ischaemic changes

Chronic infarction

Magnetic resonance imaging (MRI)

Early ischaemic changes after occlusion

of the left internal carotid artery

ISCHEMIC STROKE

• At 6.30pm, a female collapsed at a shopping mall

• At 6.40 you find a woman sitting on the bench, she is confuse but response to verbal stimuli

• Summary signs and symptoms:

– Regular heart rate and adequate perfusion

• 63-y –o woman

• Facial drop (ask patient to show teeth and smile)

Clinical syndrome: occlusion

• MCA infarction:

– Dominant hemisphere: speech

affected, comprehension and

expression speech The other side:

hemianopia

– Limbs are flaccid and areflexic

Clinical syndrome: occlusion

• ACA occlusion: contralateral weakness

and cortical sensory loss in the leg

• PCA occlusion: cortical bliness

• Lacunar infarct: occlusion of small

perforating vessels, internal capsule,

basal ganglia, thalamus, pons

• Brainstem stroke

Cerebral ischaemia

 Cerebral ischaemia can produce irreversible injury to highly vulnerable neurons in 5 minutes

 If cerebral ischaemia persists for

>6 hours, infarction of part or all of the involved vascular territory is completed

 Clinical evidence depends on the location of stroke

Duration of ischaemia

Degree of neurologic injury

Strokes are an EMERGENCY

• If patients are having a Stroke

come to the hospital right away –

CALL 9-1-1 in US (115 in Vietnam)

Case (continue…)

• 7.15pm (45munutes after symptom onset)

• Patient arrives in the ED, the nurse

immediately triage the patient to the critical area of the ED and notifies the physician of the arrival and that she is a possible

thrombolytic candidate

• What is the next step?

Once patients are at the Hospital

• Diagnostic Testing

– CT or MRI of the brain – EKG

– Carotid Ultrasound – Echocardiogram

Thrombolytics (t-PA)

Some exclusion criteria for thrombolytics

 Should preferably be given within 3 hours of symptom onset

 No other likely explanation for the neurologic symptoms

 No significant risk of bleeding

 No evidence of bleeding on head CT scans

 No evidence of early infarct sign on head CT scan

Recomemdation for TPA

• In patients with acute ischemic stroke in whom

treatment can be initiated within 3 h of

symptom onset, we recommend IV

recombinant tissue plasminogen activator

(r-tPA) over no IV r-tPA (Grade 1A).

• In patients with acute ischemic stroke in whom

treatment can be initiated within 4.5 h but not within 3 h of symptom onset, we suggest IV r- tPA over no IV r-tPA (Grade 2C)

IV TPA vs IA TPA

• In patients with acute ischemic stroke in whom

treatment cannot be initiated within 4.5 h of

symptom onset, recommend against IV r-tPA (Grade 1B).

• In patients with acute ischemic stroke due to proximal cerebral artery occlusions who do not meet eligibility criteria for treatment with IV r-tPA, recommend

intraarterial (IA) r-tPA initiated within 6 h of symptom onset over no IA r-tPA (Grade 2C).

• Merci vs Solitaire

Acetylsalicylic acid (ASA)

 Small benefit within 48 hours of stroke onset

 Delay for 24 hours if receiving thrombolytics

After recurrent stroke with taking ASA

 Consider clopidogrel or dipyramidole/aspirin

After first stroke

• In patients who do not merit or qualify for aggressive acute thrombolytic treatment, therapy with ASA is warranted

• ASA should be started within 48 hours of stroke onset

• In patients with a contraindication for ASA, dypiridamole or clopidogrel can be used

• Aspirin reduces risk of stroke by 15-20%

• Carotid endarterectomy (CEA) should be

considered for patients with large vessel

atherothrombotic disease in the internal carotid artery that causes low flow or embolic TIAs

• CEA should be done quickly

• Virtually all patients with atrial fibrillation who

have a history of stroke or TIA should be treated with warfarin in the absence of contraindications

HAEMORRHAGIC STROKE

HAEMORRHAGIC STROKE

Primary intracerebral haemorrhage

• The most common non-traumatic

causes include chronic hypertension,

aneurysms, and vascular

malformations

• Often occurs in the internal capsule

and/or basal ganglia, but it can occur

in any part of the cortex, in the pons

and cerebellum

• Clinical signs depend on the

Blood pressure control

Subarachnoid haemorrhage

• Causes

– Saccular (‘berry’) aneurysms: 70%.

– Arteriovenous malformations (AVMs): 10%.

• Drowsiness or coma may continue for hours to days.

• Signs of meningism occur after 3–12

hours: neck stiffness on passive flexion; positive Kernig’s sign

• Focal signs from a haematoma may be present, e.g limb weakness, dysphasia

Immediate management

• Regular neurological observations

• Bed rest and fluid replacement

• Analgesia for headache: codeine or

dihydrocodeine (stronger analgesics may

depress conscious level and mask

deterioration)

• Nimodipine (a calcium-channel blocker):

reduces vasospasm and morbidity/mortality)

• Control of hypertension (triple H should be considered if aneurysm is secured).

• The routine use of prophylactic

anticonvulsants is controversial, but if

seizures occur anticonvulsants should be

commenced

• Transfer to neurosurgical unit or intervenist

• TIA should not be ignored, Aspirin reduces risk

of stroke by 15-20%, warfarin for AF

• In TIA, carotid endarterectomy should be done quickly if indicated

• Ischemic stroke: Time is brain, window time

for TPA is 3 hour, may benefit up to 4,5 hour

• Proximal cerebral artery occlusions: IA TPA

within 6 hour, consider thromboectomy

• Aspirin benefit in acute stroke and longterm treatment after first stroke, other

antiplatelets should be considered

• In ICH patient: mean BP should be control

around 110 mmHg, treatment should be

started when SBP > 180 mmHg (SBP 140mmg appeared to be save)

• In SAH: transfer to the hospital which has

neurological unit or intervention radiologist