Stroke (main)
Background
- Vascular injury that reduces CBF to specific region of brain causing neuro impairment
- Accurate determination of last known time when pt was at baseline is essential
Causes
- Ischemic (87%)
- Thrombotic (80% of ischemic CVA)
- Atherosclerosis
- Vasculitis
- Arterial dissection
- Polycythemia
- Hypercoagulable state
- Infection
- Embolic (20% of ischemic CVA)
- Valvular vegetations
- Mural thrombi
- Arterial-arterial emboli from proximal source
- Fat emboli
- Septic emboli
- Hypoperfusion
- Cardiac failure resulting in systemic hypotension
- Thrombotic (80% of ischemic CVA)
- Hemorrhagic (13%)
- Intracerebral
- HTN
- Amyloidosis
- Anticoagulation
- Vascular malformations
- Cocaine use
- SAH
- Berry aneurysm rupture
- Vascular malformation rupture
- Intracerebral
Clinical Features
- Thrombotic
- Stuttering or waxing and waning
- TIA involving same vascular distribution
- Embolic
- Sudden onset of symptoms
- TIAs involving different vascular distributions
- A-fib
- Valvular replacement
- Recent MI
- Hemorrhagic
- Sudden onset of symptoms
- Preceded by severe headache
- Recent neck trauma/manipulation
Diagnosis
Anterior Circulation
Anterior Cerebral Artery (ACA)
Signs and Symptoms:
- Contralateral sensory and motor symptoms in the lower extremity (sparing hands/face)
- Left sided lesion: akinetic mutism, transcortical motor aphasia
- Right sided lesion: Confusion, motor hemineglect
Middle Cerebral Artery (MCA)
Signs and Symptoms:
- Hemiparesis, facial plegia, sensory loss contralateral to affected cortex
- Motor deficits found more commonly in face and upper extremity than lower extremity
- Dominant hemisphere involved: aphasia
- Nondominant hemisphere involved: inattention, neglect, dysarthria without aphasia
- Homonymous hemianopsia and gaze preference toward side of infarct may also be seen
Posterior circulation
- Blood supply via the vertebral vertebral artery
- Branches include, Basilar artery, PCA and PICA
Signs and Symptoms:
- Crossed neuro deficits (i.e., ipsilateral CN deficits w/ contralateral motor weakness)
- Multiple, simultaneous complaints are the rule
- 5 Ds: Dizziness (Vertigo), Dysarthria, Dystaxia, Diplopia, Dysphagia
- Isolated events are not attributable to vertebral occlusive disease (e.g. isolated lightheadedness, vertigo, transient ALOC, drop attacks)
Basilar artery
Signs and Symptoms:
- Quadriplegia, coma, locked-in syndrome
Posterior Cerebral Artery (PCA)
Signs and Symptoms:
- Unilateral headache (most common presenting complaint)
- Visual field defects (contralateral homonymous hemianopsia, unilateral blindness)
- Motor function is typically minimally affected
Posteroinferior Cerebellar Artery (PICA)
Signs and Symptoms:
- Vertigo, gait instability, limb ataxia, Headache, dysarthria, Nausea and Vomitting, Cranial Nerve abnormalities
DDX
- Seizures/postictal paralysis (Todd paralysis)
- Syncope
- Hypoglycemia
- Hyponatremia
- Meningitis/encephalitis
- Hyperosmotic Coma
- Labyrinthitis
- Drug toxicity
- Lithium, phenytoin, carbamazepine
- Bell's Palsy
- Complicated migraine
- Meniere Disease
- Demyelinating disease (MS)
- Conversion disorder
Work-Up
- Bedside glucose
- Bedside Hb (polycythemia)
- CBC
- Chemistry
- Coags
- Troponin
- ECG (esp A-fib)
- Head CT
- Primarily used to exclude intracranial bleeding, abscess, tumor, other stroke mimics
- Also consider:
- Pregnancy test
- CXR (if infection suspected)
- UA (if infection suspected)
- Utox (if ingestion suspected
Treatment
Ischemic
- tPA AND non-tPA candidates:
- Prevent dehydration
- Maintain SpO2 >92%
- Prevent fever
- Controversial
tPA Candidate
- tPA
- Hypertension
- Lower SBP to <185, DBP to <110
- Options:
- Labetalol 10–20mg IV over 1–2 min; may repeat x1 OR
- Nitroglycerin paste, 1–2 in. to skin OR
- Nicardipine 5mg/hr, titrate up by 2.5mg/hr at 5-15min intervals; max dose 15mg/hr
- When desired blood pressure attained reduce to 3mg/hr
Non-tPA Candidate
- Hypertension
- Allow permissive HTN unless SBP >220 or DBP >120 (lower by 10-25%)
- Aspirin 325mg (within 24-48hr)
- Anticoagulation not recommended for acute stroke (even for A-fib)
Hemorrhagic
Cerebellar
- Early neurosurgical consultation is needed (herniation may lead to rapid deterioration)
- See Cerebellar Stroke
See Also
- Transient Ischemic Attack (TIA)
- Thrombolysis in Acute Ischemic Stroke (tPA)
- CVA (Post-tPA Hemorrhage)
- Intracranial Hemorrhage (ICH)
- Subarachnoid Hemorrhage (SAH)
- Cervical Artery Dissection
- NIH Stroke Scale
- Stroke syndromes
- Cerebellar Stroke
External Links
Source
- Tintinalli
- UpToDate
- AHA/ASA Acute Stroke Guidelines
- EMCrit