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MANAGEMENT OF STROKE
DR W.D.A.Patirana
MBBS.MD
WHO definition
Clinical syndrome typified by rapidly
deveoloping signs of local or global
disturbance of cerebral functions, lasting
more than 24hrs or leading to death with
no apparent causes other than of vascular
origin
Introduction
• Stoke: sudden neurological deficit of presumed vascular origin
• It’s a syndrome rather than a single disease• Acute stroke is now a treatable condition that
deserves specialised attention• A senior clinician should review all pts with
presumed stroke (class B recommendation)• Drug Rx and specialised care both influence
survival and recovary
Assesing the patient
• Pts should be assessed at hospital immediately after stroke
• Hyperacute treatments such as thrombolysis must be administered within 3-6 hrs
• Stroke is a clinical diagnosis, but imaging is required to differentiate between ischemic and primary intracerebral h’age
• Following can be used to diagnose and predict prognosis– Eivdence of motor, sensory or cortical dysfunction– Hemianopia
Pathophysiology
• For practical purposes – 2 types of stroke (after excluding SAH)– Ischaemic: 85%– 1ry h’age: 15%
• H’ge causes direct neuronal injury and pressure effect causes adjacent ischemia
• 1ry ischaemia results from atheroembolic occlusion or embolism
• Usual sources of emboli are LA in pts with AF or LV in MI/LVF
Characteristics of subtypes of stroke
Lacunar PACI TACI Post
Signs Motor or sensory only
2 of the following: motor or sensory, cortical, hemianopia
All of: motor or sensorycortical, hemianopea
Hemianopia, brainstem, cerebellar
%dead at 1yr
10 20 60 20
%depend at 1 yr
25 30 35 20
Signs to be looked for
• Conscious level
• Neurological signs
• BP
• HR/rhythm
• Heart murmurs
• Peripheral pulses
• Systemic signs of infection or neoplasm
Death rate after stroke
30 days 1 year 5 years
Ischaemic stroke
10 23 52
ICH 52 62 70
SAH 45 48 52
Conditions that can mimick stroke
Diagnosis Diagnostic features
Decompression of previous stroke
Evidence of infection such as urinary or respiratory tract; metabolic dist.
Cerebral neoplasm (1ry or 2ry) Less abrupt; 1ry tumor or 2ry (lung or breast CA)
SAH Recent head injury
Epileptic seizures Possible previous fits
Traumatic brain injury H/O trauma
migraine Less abrupt onset; followed by headache; young pt
Multiple sclerosis Less abrupt onset, possible previous epi
Cerebral abscess Infection
Investigations of stroke
• All should have a CTwithin 48hrs to distiguish between ischaemic and h’gic stroke
• Imaging should be urgent in – Depressed conscious level, fluctuating symptoms,
papilloedema, neck stiffness, fever, severe headache, previous trauma, anticoagulant treatment or bleeding diathesis (B)
• MRI is superior, because it also assess blood flow and perfusion of the brain/detect wether lesion is old or new and identify carotid stenosis
• Imaging will also identify stroke mimicking conditions
• But a low grade glioma could still be difficult to be differentiated from cerebral infarction
Investigations of stroke
• All patients– CT/MRI– ECG– CXR– FBC– Clotting screen– SE/creatinine– Plasma glucose
Investigations of stroke
• Sub groups– Carotid duplex scanning
– ECHO– Thrombophilia screen– Immunology screen– Syphillis serology– Cerebral angiography (Rarely)
Justification for echo
• AF• HF• MI within 3/12• ECG abnormalities
– MI
– IHD
– BBB
• Heart murmur• Peripheral embolism• Clinical events in >2
territories– R & L hemisphere– Ant & post circulation
• >/= cotical events (in same territory) unless severe carotid disease
Investigations – to what extent
• Depends on several factors– Likely degree of recovary
– Presence of obvious risk factors– Age of the pt (younger pts likely to have
identifiable cause such as inflammatory or clotting dissorder)
• Ix better be restricted to tests that will help in the management
Stroke unit• Stroke unit should be centred in a hospital• Should be staffed by
– Multidisciplinary team with expertise in stroke care (A)– Team should work to agreed protocols for common problems (A)– Should provide educational programmes for staff, pts and carers
• Stroke unit trialist’s collobaration– Stroke units compared to alternatives showed reduction in odds
ration for death recorded at follow up (OR 0.86)– Odds ratio of death, instituitionalised care and death or
dependency were significantly less– Outcomes were independent of age, gender and stroke severity
and appeared to be better in stroke units based in a geographincally discrete ward
– No increase in hospital stay in stroke unit , mortality and institutionalisation rates at one year were lower in
patients who received care on the stroke ward– The benefits of stroke unit care have been shown to persist at 10
years after initial stroke
Emergency management
• Within the 1st hour after cerebral ischaemia, part of the brain is under threat of death
• The densly ischaemic area will inevitably die, but there is also tissue that could be salvaged
• At this stage oxygenation, haemodynamic and metabolic factors are crucial
Emergency management
• The emergency managemet of stroke requires– Medical stabilisation– Assesment of factors that may lead to complications
• Swallowing • hydration
– It is important to keep physiological variables such as hydration,– temperature, nutrition, and oxygenation within normal range– in the acute phase of stroke (C)– Thrombolysis may be considered–
Swallowing and feeding
• Dysphagia in ~35%– Unrecognised in mild stroke – But associated with poor outcome
• Aspiration• Pnuemonia• Poor nutrition
• They should be fed through NG or percutaneous endoscopic feeding tube
• Dysphagia Mx involves: – Initial swallow screen– Diet modification– Compensatory swallowing techniques
-reduces aspiration pneumonia
Communication and speech
• can affect in a variety of ways, including – impaired motor speech production (dysarthria)– impaired language skills (dysphasia) – Impaired planning and execution of motor speech (articulatory
dyspraxia)
• needs to be assessed by a speech and language therapist
Acute treatment of stroke
• Asprin: in most patients– 2 large trials (160-300mg/d by PO/NG/ Rectum) started within
48hrs of stroke, reduces subsequent death and disability– NNT- 77 (reducing risk by reducing reinfarction)– For 1000 pts –
• 12 avoid death and dependency• Risk of h’age minimal (1-2/1000)• Early asprin is beneficial
- if a diagnosis of haemorrhage is considered CT/MRI is essential before asprin
– But if CT is not availble and ischaemic stroke is highly suspected may give asprin
• IST(International Stroke Trial) and CAST (Chinese acute stroke trial) combined
– 40,000 pts– Significant decrease in death and
dependency at 6/12 if asprin is given immediately
– 13 more pts alive per 1000 Rxed– Increase in ICH – 2 per 1000
– Reduction in recurrence - 7 per 1000
• Anticoagulation has no net benefit
– Decreases recurrent ischaemic stroke (9 per 1000 Rxed) and pulmonary emboli (4 per 1000 Rxed)
– But 9 per 1000 increase in ICH– But it has definitive place in 2ry prevention– Immediate anticoagulation in AF is not
advised
– There is evidence for acute anticoagulation in the specific stroke syndrome of cerebral venous thrombosis
Acute treatment of stroke
• Thrombolysis– Standard acute Rx in USA, Australia and most
european countries– Type of drug and timing important– NINDS trial: Alteplase (tPA) within 3 hrs increases
the chances of near complete recovary (NNT-7)– 3-4x increase in ICH– 20% reduction in death and dependency– Rx after 6 hrs less effective (NNT-12)– Complications: intra or extracranial h’age
Acute treatment of stroke
– Contra indications to thrombolysis:• Seizure at onset• Pre Rx BP >185/110
• Major infarct on CT
• Previous ICH
• Recent MI• Recent or intended surgery• Use of anticoagulants
Acute treatment of stroke -- BP
• Withhold antihypertensives for 10 days• Indications for early Rx of high BP
– Evidence of pre existing HBP• Documented previous HT:clinic recors etc• Evidence of target organ damage
Hypertensive retinopathy, LVH on ECG
– Evidence of hypertensive emergancy• HT encephalopathy• LVF
– BP is very high• SBP >220-240• DBP >120
Complications of stroke
• Hyperglycaemia**• Hypertension**• Fever**• Infarct extension or
bleeding• Cerebral oedema• Herniation • coning
• Aspiration• Pneumonia• UTI• Cardiac dysrrhythmia• Recurrence
• DVT• PE
Rehabilitation
• Aims– Restore function– Reduce the effects of stroke on pt and theirs carers– Regain independence and maximise ability in all
activities of daily living• Should start early during recovery• Once pt is medically stable, should be
transferred to a stroke rehabilitation unit• Formal rehabilitation at a centre reduces death,
disability and hospital stay (NNT-12)
Summary of acute management of stroke
• Admit to stroke unit – improves survival & dependency
• Immediate CT• Leg stockings (CLOTS trial)• Asprin 300mg stat and 75mg thereafter• Avoid heparin• Thrombolysis (Randamise)• Relaxed about BP• Nursing, swallowing and nutrition
STROKE SECONDARY
PREVENTION
Secondary prevention
• Should start shortly after admission, except BP control
• All pts should be offered– Life style guidance– Stop smoking– Reduce saturated fat, alcohol and salt– Asprin for life
Risk of recurrence after stroke or TIA
• Stroke:– 8% per year
• TIA– 8% risk of stroke in the first month– 5% risk of stroke a year thereafter
– 5% risk of MI a year
Modifiable risk factors for stroke
• HBP• Smoking• DM• Diet: high salt & fat,
low K & vitamins• Excess alcohol
• Morbid obesity • Low physical exercise• Low temperature• Cholesterol
concentrations – atleast in pts with CAD
Management of risk factors
• Smoking:– Important correctable risk factors
– Risk returns to that of a non smoker within 3-5 yrs of cessation
Alcohol and risk of stroke
• Protective effect with light to moderate intake
• One drink a day – reduces stroke
• If more than one drink a day –risk increases
Management of risk factors
• Blood pressure– HT should be treated 1 or 2 weeks after the
stroke– Rx reduces
• Recurrence of fatal and non fatal stroke by 28%
– Pts at high risk of further stroke derive greatest benefit (eg: elederly)
– Target BP recommended by British Hypertension Society is <140/85
• PROGRESS study:– irrespective of baseline BP– Pts treated with Perindropril and
indapamide had a reduction in BP of 12/5– And reduced stroke risk of 43%–
• HOPE study– 32% relative risk reduction in 1ry and 2ry
stroke prevention in 9297 high risk pts with ramipril
– Base line BP was 139/79– Reduction in BP was only 3.8/2.8– Efficacy of ACEI may explained by anti-
inflammatory effect and plaque stabilization
Management of risk factors
• Role of cholesterol – contraversial
• But statins reduce risk of stroke in pts with CAD
• Use of statins after a athersclerotic stroke or TIA probably reduces recurrent events and IHD
Heart protection study
• Over 20,000 pts with high risk of vascular disease aged 40-80
• There were 1820 pts with history of non disabling stroke or TIA
• All were randomised to simvastatin 40mg/d or placebo for 5 years, independent of baseline cholesterol
• Simvastatin pts showed highly significant 25% reduction in incidence rate of 1st stroke
• The benefits were seen across all age ranges and base line cholesterol levels
Management of risk factors
• Diabetes:– Confers substantial dissadvantage for
• Survival
• Functioning outcome on pts with acute stroke
• Plasma glucose should be normalised early• BP targets for diabetics are lower
BP targets for non diabetic and diabetic stroke pts
No DM DM
Titrate to DBP </=85 </=80
Optimal BP <140/85 <130/80
Suboptimal BP >/=150/90 >/=140/85
Atrial fibrillation and stroke
• Over the age of 60 – 2-5% Have AF and associated with a stroke rate of 4-5%
• Meta-analysis of warfarin in Non rheumatic AF – 60-65% reduction in stroke (INR 2-3)
• With asprin 20% reduction
Atrial fibrillation and stroke – CHADS2 Scheme for risk assesment
• C – Congestive cardiac fairlure 1
• H – Hypertension 1
• A - Age >75 1
• D – Diabetes 1
• S – Past Stroke or TIA 2
Atrial fibrillation and stroke
• If patients aged 65-95 with AF– Score 0 – risk is 1.9– Score 6 –risk is 18.2
• Asprin is sufficient in patients with score 0• Warfarin is the choice if score 1 or more• Warfarin is under used, especially in
elderly (appropriate anticoagulation used in only 30-60%)
contraindications to long term warfarin
• GI bleeding
• Active peptic ulcer
• Frequent falls
• Alcohol misuse
• History of ICH
• Age by itself is not a contraindication
Anti platelet therapy
• Asprin
– should receive antiplatelet Rx as first line– Benefits of asprin conclusively proven– ASA – initial dose of 300mg & followed by 75mg/d
• Dipyridamol
– Dipyridamole MR 200mg BD has independent and additive effect to low dose asprin in preventing stroke, but not coronary events or overall mortality
– So routine addition of dipyridamol may be cost effective– Dipyridamol alone does not prevent cardiac events
Carotid endarterectomy for symptomatic
carotid stenosis in elderly patients
• Efficacy of CEA in symptomatic carotid stenosis >70% is well established
• Elderly – surgical risk is higher, but benefits even greated
• NASCET Trial– Absolute risk reduction is 28.9% in >75yrs– 15.1% for 65-74yrs– 9.7% for below 65yrs
THANK YOU