Stroke/TIA Flashcards
ANTERIOR stroke syndromes:
MCA
Contralateral:
HEMIPLEGIA: ARMS> legs
LOWER face
Hemisensory loss
Homonymous hemianopia
Dysphasia/ aphasia (DOM SIDE L)
Hemi Neglect (NON DOM R)
ACA
Also contralat hemisensory/hemiplegia, but:
LEGS > arms
Frontal functions (executive, personality)
Urinary incontinence + perineum
POSTERIOR STROKE syndromes:
1- CEREBELLAR stroke
- Ataxia
- Vertigo
- Nystagmus (direction-changing)
- Dysarthria
- Rebound (slip out of grip)
- DDK
- Dysmetria
2- PCA/ OCCIPITAL stroke
- Homonymous hemianopia (contra)
- Contralateral homonymous hemianopia with MACULAR SPARING
- Visual agnosia
- Facial blindness
3- BRAINSTEM stroke
- CROSSED signs- cranial nerves one side, motor/sensory the other
- Decerebrate
*PICA stroke (Wallenberg)
4- BASILAR stroke
- LOC (RAS)
- Locked-in (pons)
4- THALAMIC stroke
- Many!
Wallenberg Syndrome:
Lateral medullary syndrome (PICA)
CN 9-12
Ataxia (fall to side of lesion), vertigo
Dysphagia (gag loss, hoarse)
Ipsi Horner’s
Ipsi pain/ temp loss to FACE
+ CONTRAlat pain/temp loss to BODY
What is a ‘lacunar’ stroke?
Small perforating vessels
Affects small areas, deep in brain
Clinically subtle
Associated with chronic HTN
What features suggest POSTERIOR STROKE over peripheral cause of vertigo:
More gradual onset
Vertigo milder
N&V rare
Unaffected by movement/ position
Ataxia/ trunkal instability prominent
No ear symptoms
Other brainstem or cerebellar signs
Stroke RFs/ older
HINTS exam:
Indicated when persistent acute vestibular syndrome indicate ?central cause:
HEAD IMPULSE
Normal person/ Central has VO reflex: can stay fixed on nose.
- Peripheral: Abnormal corrective saccade as VO gone
- Central: VO unaffected. As per normal person.
NYSTAGMUS
- Peripheral: Horizontal, unidirectional
TOWARD affected side.
- Central: Pure torsional, Pure vertical, Bidirectional
TEST of SKEW
- Peripheral: stays focused
- Central: vertical correction
ROSIER scale
Recognition of Stroke in the Emergency Room.
>0 = stroke likely
0 = stroke unlikely
Widely recommended
Only one validated for this purpose
APPROACH to acute stroke:
- CODE stroke
- Rapidly assess:
–> ?last seen normal
–> Contraindications to lysis
–> BSL + bloods
–> CONSIDER ?DISSECTION + mimics
–> ECG -
Immediate neuroimaging
–> Ideal: CT series incl. perfusion scan
–> Other: Thin-slice CT, MRI. - NIHSS score
- If not a lysis candidate: antiplatelet load, medical Mx incl. BP <220/120, +/- thrombectomy/ catheter-directed thrombolysis.
- If for lysis: ensure BP <185/110, withhold AP, lyse.
Ongoing Mx:
- NBM + NGT
- Neuroprotective
- Stroke unit
What NIHSS scores preclude thrombolysis?
<5
>25
Time windows for reperfusion in acute ischaemic stroke:
Thombolysis
Was 3 - 4.5 hours since last seen normal(ECASS-II)
(up to 9 hours if favourable perfusion scan)
Thrombectomy
6 hours
(Up to 24 if significant penumbra)
Indications for thrombolysis in stroke:
- 18 years +
- Diagnosis of ischaemic stroke
- Symptoms deemed ‘disabling’
- NIHSS not <4, not >25
- Will get lysis within 3 (to 4.5 ECAS-III) hours of symptom onset
- If unknown onset (ie. woke): perfusion showing <1/3 MCA territory + penumbra (and liaison with Stroke physician) and will let lysis within 4.5 hours of recognition
ABSOLUTE CONTRAindications to lysis in stroke:
Stroke too severe (NIHS <4) or too mild (>25)
CVA in last 3/12
Spontaneous ICH ever
AVM/ mets
Significant trauma
Dissection
Active bleeding
RELATIVE CONTRAindications to lysis in stroke:
Pregnancy
CPR >10mins
Anticoagulated
SBP >180
Major surgery < 3/52
Isch CVA >3/12 ago
GI bleed incl PUD
Non-compressible vascular puncture
SEIZURE” Todd’s paresis may overestimate deficit…
ACEM’s position on thrombolysis:
ACEM worried evidence wasn’t solid, so ran an independent review.
Outcome:
- No mortality benefit
- Potential functional benefit
- NNT/ NNH not great.
…always discuss above with patient.
Not clear if best.
Lysis only if:
- Access to Stroke Team (incl. telemed)
- Streamlined prehosp/ED/allied response
- Immediate imaging/ interpretation
- Data collection
Numbers needed to treat/harm for thrombolysis in acute ischaemic stroke:
NNT for functional independence: 10-13 (12)
NNH for symptomatic ICH: 42
NNH for death: 122
No mortality benefit, only functional.
Thombolysis dosing in acute ischaemic stroke:
Alteplase
0.9mg/kg (max 90mg) IV
10% as bolus, rest over 1 hour
Blood pressure targets in acute stroke:
Ischaemic:
<220/120
<185/110 pre and post lysis
Haemorrrhagic:
<140/90
Thrombectomy in acute ischaemic stroke:
Less effective than lysis
Option for LARGE vessel occlusion only (MCA, ICA, basilar)
Do within 6 hours (up to 24 if favourable penumbra)
Antiplatelet/ anticoagulation in ischaemic stroke/ TIA:
ALL should get an antiplatelet load initially, as soon as ICH/ SOL ruled out,
except if for lysis.
No antiplatelet within 24/24 of lysis
Ongoing:
–> Aspirin/dypyridamole 25/200 BD
OR
–> Clopidogrel 175mg daily
- Aspirin alone is inferior
AntiCOAGULATE only if:
- non-endocarditis cardioembolic source (not ED decision)
Discuss CT in acute stroke:
- Fast initial test to rule out ICH/SOL to guide rapid Tx decisions
- MAY see ‘hyperdense MCA sign’ if lucky.
- Most nc-CTB will be normal in first 24+ hours of ischaemic stroke
- Thin-slice ideal
- Even better is stroke series:
–> Thin slice CT (ICH/ SOL)
–> CTA from arch (clot location/ size)
–> Perfusion (penumbra)
Hyperdense artery (MCA) sign
Not seen often (30%), but very specific for isch. stroke.
More likely to see if thin slice CT (or CTA)
Other imaging options in acute stroke:
CTA alone
–> Primarily for Dx location/cause in an ICH seen on nc-CTB
MRI
–> Definitive for ischaemic stroke (DWI image)
–> Just as accurate for ICH/isch
–> Can combine with MRA
—> Not appropriate in acute code stroke
Angiography
–> Can do thrombectomy
–> If CTA/MRA equivocal/ vascular lesion seen/ suspected
________
- Acute stroke (within 4.5 hrs) = stroke series incl. CT perfusion
- ‘Missed’ stroke (longer) = MRI (DWI)
- CTA not enough!!!!
Causes of stroke to consider in young adults with stroke:
Dissection (20%)
Substances (amphetamine, cocaine, LSD
Cardioembolic (HOCM, dilated CM, RHD, endocarditis)
Air embolism (diving)
Migrainous/ OCP
Underlying: Ca, procoag
Stroke mimics:
Focal seizure/ post-ichtal/ Todd’s paresis
Hemiplegic migraine
Encephalopathy
SOL
MS exacerbation
Toxic (antiepileptics)
Functional/ facticious
Hypoglycaemia, hypoNa
DISSECTION (DON’T LYSE THIS!!)
What is the risk of a stroke following a TIA episode?
HIGH
10-20% will stroke within 3 months
*HALF of these will be within 40 hours
Aggressive TIA Mx reduces risk by 80%
What features in a TIA presentation infer HIGH risk of subsequent stroke:
- Crescendo Sx
- AF
- Bruit
- Anticoagulated
- ABCD2 score >4
APPROACH to TIA
- ECG on presentation (?AF)
-
Immediate rule out of ICH/SOL
–> MRIB best
–> CTB non con at minimum (CTA at RHH) - Antiplatelet load
Timing of complete work up depends on risk:
- ‘High risk’* or ABCD2 4+ = admit Stroke Unit for WU
- ABCD2 <4 = can DC, WU within 48 hours
COMPLETE WORK UP
- MRIB (if not already)
- Carotid imaging (anterior Sx)
–> Doppler, CTA, MRA
- Echo (if cardioembolic suspected)
- Secondary RFs
–> HTN, BSL, lipids,+- Holter
On DC:
- Antiplatelet and statin for all (regardless of lipid profile)
- Consider anticoag instead if cardio source (NOT endocarditis)
DEFINITIVE
- Endarterectomy if carotid stenosis >50%
- Medical Mx only if <, or posterior
ABCD2 score. List components, and describe use:
- Risk of stroke in TIA at 2, 7 and 90 days
- Risk stratify for disposition
- If 4+, admit to stroke unit for work up. If less than 4, can go home and complete work up within 48 hours.
Indications for carotid endarterectomy:
Stenosis >50%
What is RIND?
‘Reversible Ischaemic Neurological Deficit’- Like a prolonged TIA!
Lasts >24 hours and has resolved by 1 week
Is neglect a dominant or non-dominant hemisphere problem?
Non-dominant
Is aphasia a dominant or non-dominant hemisphere problem?
Dominant
