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Emergency and Acute Medicine - Cerebrovascular Accident (Stroke)
Overview
A cerebrovascular accident (CVA) results from interruption of blood flow to a specific brain region. Clinical deficits correspond to the vascular territory involved. Onset may be abrupt and complete or stepwise and fluctuating. Stroke accounts for ~1 in 18 deaths in the United States, with ~610,000 new cases annually.
Predisposing Factors
Hypertension, diabetes mellitus, smoking, coronary artery disease, cardiac dysrhythmias, peripheral vascular disease, oral contraceptive use, polycythemia vera, sickle cell disease, antithrombin III deficiency, protein C or S deficiency.
Pathologic Mechanisms
Ischemic stroke includes thrombotic, embolic, dissection-related, or hypoperfusion etiologies. Thrombotic stroke most often results from clot formation at an ulcerated atherosclerotic plaque or from sludging states (sickle cell disease, polycythemia vera, protein C deficiency). Embolic stroke arises from cardiac mural thrombi (atrial fibrillation, mitral stenosis, cardiomyopathy, CHF, MI), prosthetic or abnormal valves, carotid or aortic arch plaques, atrial myxoma, or ventricular aneurysm thrombi. Arterial dissection may involve carotid arteries or be associated with arteritis (giant cell, Takayasu) or fibromuscular dysplasia. Global ischemic stroke results from systemic hypotension due to sepsis, hemorrhage, or shock. Hemorrhagic stroke includes intracerebral and subarachnoid hemorrhage.
Pediatrics: Usually secondary to underlying disease (sickle cell disease, leukemia, infection, blood dyscrasia); younger children often present with seizures or altered mental status.
Clinical Features
History focuses on exact time of onset or last known normal, trauma or surgery, medications, confusion, headache, vertigo, and focal neurologic deficits.
General exam may show Cheyne–Stokes respirations, apnea, hypertension, dysrhythmias, or murmurs.
Anterior cerebral artery involvement causes contralateral leg-predominant weakness and sensory loss, apraxia, confusion, and impaired judgment.
Middle cerebral artery involvement causes contralateral face and arm weakness, hemisensory loss, homonymous hemianopsia, aphasia or dysarthria, and agnosia.
Posterior cerebral artery involvement causes cortical blindness, visual agnosia, memory impairment, altered mental status, third-nerve palsy, or hemiballismus.
Vertebrobasilar strokes cause vertigo, diplopia, nystagmus, visual field defects, and crossed cranial nerve and motor deficits; basilar artery occlusion may lead to quadriplegia, locked-in syndrome, or coma.
Watershed infarcts produce proximal limb weakness with sparing of face, hands, and feet.
Initial Evaluation Priorities
Perform a focused neurologic examination and calculate the NIH Stroke Scale when possible. Obtain emergent noncontrast head CT to differentiate ischemic from hemorrhagic stroke; early CT may be normal within 24–48 hours. Goals include CT completion within 25 minutes, interpretation within 45 minutes, and thrombolytic administration within 60 minutes if indicated. If CT is negative but subarachnoid hemorrhage is suspected, perform lumbar puncture. Obtain ECG, oxygen saturation, and rapid blood glucose.
Diagnostic Studies
Laboratory tests include CBC, electrolytes, renal and liver function, PT/PTT, urinalysis, and ESR when indicated. Additional studies may include cardiac enzymes, pregnancy test, toxicology screen, alcohol level, ABG, and blood cultures. Imaging may include MRI for early ischemia, chest radiograph, and carotid ultrasound. ECG evaluates for arrhythmia; lumbar puncture is required if CT is nondiagnostic and SAH remains suspected.
Key Differentials
Intracranial hemorrhage, hypoglycemia, seizure with Todd paralysis, conversion disorder, transient global amnesia, encephalitis or meningitis, peripheral neuropathy, intracranial abscess, migraine, air embolism, TIA, metabolic encephalopathy, neoplasm, vasculitis, multiple sclerosis, compressive myelopathy, vestibulitis, medication or toxin effects.
Prehospital Considerations
Patients may have impaired movement or communication. Field neurologic assessment should include level of consciousness, GCS, speech, facial symmetry, gait, and motor deficits. Fingerstick glucose is essential.
Stabilization Measures
Ensure airway protection; provide supplemental oxygen at 2–4 L/min. Intubation may be required for airway control or ICP management. For altered mental status, administer naloxone and thiamine and correct hypoglycemia.
Emergency Department Management
Treat severe hypertension only if SBP >220 mm Hg or DBP >120 mm Hg, or if required for comorbid conditions; initial target is <180 />10 mm Hg. Control seizures with benzodiazepines followed by fosphenytoin or phenytoin. Maintain euvolemia and normothermia.
Thrombolysis: For ischemic stroke only, administer IV alteplase within 4.5 hours of symptom onset if criteria are met. Avoid antiplatelet and anticoagulant therapy for 24 hours post-tPA.
Contraindications: Prior intracranial hemorrhage, recent stroke or head trauma (<3 months), major surgery (<14 days), uncontrolled hypertension, bleeding diathesis, recent mi, inr>1.7, platelets <100,000, intracranial neoplasm, seizure at onset, rapidly improving symptoms, pregnancy, recent internal bleeding, glucose <50 mg />L, age <18 years.< />pan>
3-4.5 hour exclusions: Age >80, oral anticoagulant use, NIHSS >25 or >1/3 MCA involvement, prior stroke plus diabetes.
Manage cerebral edema with head elevation, controlled ventilation (PaCO₂ 35–40 mm Hg), mannitol, and neurosurgical consultation when indicated. Selected patients may undergo intra-arterial thrombolysis or mechanical thrombectomy.
Medications
First line: Alteplase 0.9 mg/kg IV (max 90 mg), aspirin 81–325 mg PO/PR, labetalol IV bolus and infusion.
Second line: Clopidogrel, diazepam, enalapril, hydralazine, mannitol, nicardipine, nitroprusside, trimethaphan.
Pediatrics: Heparin or LMWH often used; pediatric stroke consultation available via 1-800-NOCLOTS.
Disposition
All acute strokes require hospital admission. ICU admission is indicated for depressed consciousness, hemodynamic instability, serious arrhythmias, elevated ICP, or tPA administration.
Discharge may be considered for completed strokes days to weeks old in patients who are functionally independent or have reliable support.
Follow-Up Care
Neurology consultation, primary care follow-up, and rehabilitation services including speech and occupational therapy.
Clinical Pearls
Document prehospital observations carefully. Accurate symptom onset time is critical for thrombolysis eligibility. Avoid rapid BP reduction to prevent cerebral hypoperfusion. Door-to-needle time goal is under 60 minutes.
Overview
A cerebrovascular accident (CVA) results from interruption of blood flow to a specific brain region. Clinical deficits correspond to the vascular territory involved. Onset may be abrupt and complete or stepwise and fluctuating. Stroke accounts for ~1 in 18 deaths in the United States, with ~610,000 new cases annually.
Predisposing Factors
Hypertension, diabetes mellitus, smoking, coronary artery disease, cardiac dysrhythmias, peripheral vascular disease, oral contraceptive use, polycythemia vera, sickle cell disease, antithrombin III deficiency, protein C or S deficiency.
Pathologic Mechanisms
Ischemic stroke includes thrombotic, embolic, dissection-related, or hypoperfusion etiologies. Thrombotic stroke most often results from clot formation at an ulcerated atherosclerotic plaque or from sludging states (sickle cell disease, polycythemia vera, protein C deficiency). Embolic stroke arises from cardiac mural thrombi (atrial fibrillation, mitral stenosis, cardiomyopathy, CHF, MI), prosthetic or abnormal valves, carotid or aortic arch plaques, atrial myxoma, or ventricular aneurysm thrombi. Arterial dissection may involve carotid arteries or be associated with arteritis (giant cell, Takayasu) or fibromuscular dysplasia. Global ischemic stroke results from systemic hypotension due to sepsis, hemorrhage, or shock. Hemorrhagic stroke includes intracerebral and subarachnoid hemorrhage.
Pediatrics: Usually secondary to underlying disease (sickle cell disease, leukemia, infection, blood dyscrasia); younger children often present with seizures or altered mental status.
Clinical Features
History focuses on exact time of onset or last known normal, trauma or surgery, medications, confusion, headache, vertigo, and focal neurologic deficits.
General exam may show Cheyne–Stokes respirations, apnea, hypertension, dysrhythmias, or murmurs.
Anterior cerebral artery involvement causes contralateral leg-predominant weakness and sensory loss, apraxia, confusion, and impaired judgment.
Middle cerebral artery involvement causes contralateral face and arm weakness, hemisensory loss, homonymous hemianopsia, aphasia or dysarthria, and agnosia.
Posterior cerebral artery involvement causes cortical blindness, visual agnosia, memory impairment, altered mental status, third-nerve palsy, or hemiballismus.
Vertebrobasilar strokes cause vertigo, diplopia, nystagmus, visual field defects, and crossed cranial nerve and motor deficits; basilar artery occlusion may lead to quadriplegia, locked-in syndrome, or coma.
Watershed infarcts produce proximal limb weakness with sparing of face, hands, and feet.
Initial Evaluation Priorities
Perform a focused neurologic examination and calculate the NIH Stroke Scale when possible. Obtain emergent noncontrast head CT to differentiate ischemic from hemorrhagic stroke; early CT may be normal within 24–48 hours. Goals include CT completion within 25 minutes, interpretation within 45 minutes, and thrombolytic administration within 60 minutes if indicated. If CT is negative but subarachnoid hemorrhage is suspected, perform lumbar puncture. Obtain ECG, oxygen saturation, and rapid blood glucose.
Diagnostic Studies
Laboratory tests include CBC, electrolytes, renal and liver function, PT/PTT, urinalysis, and ESR when indicated. Additional studies may include cardiac enzymes, pregnancy test, toxicology screen, alcohol level, ABG, and blood cultures. Imaging may include MRI for early ischemia, chest radiograph, and carotid ultrasound. ECG evaluates for arrhythmia; lumbar puncture is required if CT is nondiagnostic and SAH remains suspected.
Key Differentials
Intracranial hemorrhage, hypoglycemia, seizure with Todd paralysis, conversion disorder, transient global amnesia, encephalitis or meningitis, peripheral neuropathy, intracranial abscess, migraine, air embolism, TIA, metabolic encephalopathy, neoplasm, vasculitis, multiple sclerosis, compressive myelopathy, vestibulitis, medication or toxin effects.
Prehospital Considerations
Patients may have impaired movement or communication. Field neurologic assessment should include level of consciousness, GCS, speech, facial symmetry, gait, and motor deficits. Fingerstick glucose is essential.
Stabilization Measures
Ensure airway protection; provide supplemental oxygen at 2–4 L/min. Intubation may be required for airway control or ICP management. For altered mental status, administer naloxone and thiamine and correct hypoglycemia.
Emergency Department Management
Treat severe hypertension only if SBP >220 mm Hg or DBP >120 mm Hg, or if required for comorbid conditions; initial target is <180 />10 mm Hg. Control seizures with benzodiazepines followed by fosphenytoin or phenytoin. Maintain euvolemia and normothermia.
Thrombolysis: For ischemic stroke only, administer IV alteplase within 4.5 hours of symptom onset if criteria are met. Avoid antiplatelet and anticoagulant therapy for 24 hours post-tPA.
Contraindications: Prior intracranial hemorrhage, recent stroke or head trauma (<3 months), major surgery (<14 days), uncontrolled hypertension, bleeding diathesis, recent mi, inr>1.7, platelets <100,000, intracranial neoplasm, seizure at onset, rapidly improving symptoms, pregnancy, recent internal bleeding, glucose <50 mg />L, age <18 years.< />pan>
3-4.5 hour exclusions: Age >80, oral anticoagulant use, NIHSS >25 or >1/3 MCA involvement, prior stroke plus diabetes.
Manage cerebral edema with head elevation, controlled ventilation (PaCO₂ 35–40 mm Hg), mannitol, and neurosurgical consultation when indicated. Selected patients may undergo intra-arterial thrombolysis or mechanical thrombectomy.
Medications
First line: Alteplase 0.9 mg/kg IV (max 90 mg), aspirin 81–325 mg PO/PR, labetalol IV bolus and infusion.
Second line: Clopidogrel, diazepam, enalapril, hydralazine, mannitol, nicardipine, nitroprusside, trimethaphan.
Pediatrics: Heparin or LMWH often used; pediatric stroke consultation available via 1-800-NOCLOTS.
Disposition
All acute strokes require hospital admission. ICU admission is indicated for depressed consciousness, hemodynamic instability, serious arrhythmias, elevated ICP, or tPA administration.
Discharge may be considered for completed strokes days to weeks old in patients who are functionally independent or have reliable support.
Follow-Up Care
Neurology consultation, primary care follow-up, and rehabilitation services including speech and occupational therapy.
Clinical Pearls
Document prehospital observations carefully. Accurate symptom onset time is critical for thrombolysis eligibility. Avoid rapid BP reduction to prevent cerebral hypoperfusion. Door-to-needle time goal is under 60 minutes.
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