What are the steps for a stroke workup?

Stroke Workup: A Systematic Approach

For any patient presenting with suspected acute stroke, immediately obtain non-contrast CT head within 30 minutes of arrival to differentiate ischemic from hemorrhagic stroke, followed by vascular imaging and cardiac evaluation. 1, 2, 3

Immediate Initial Assessment (Within 30 Minutes)

Brain Imaging - First Priority

• Non-contrast CT head must be completed within 30 minutes to exclude intracranial hemorrhage and identify early ischemic changes 1, 2, 3
• MRI with diffusion-weighted imaging (DWI) is an acceptable alternative if immediately available and does not delay treatment, though CT is typically faster 1, 3
• Never use contrast-enhanced CT initially as it may obscure hemorrhage 3

Vascular Imaging - Concurrent with Brain Imaging

• CT angiography (CTA) from aortic arch to vertex should be performed immediately if patient presents within 6-24 hours and is potentially eligible for endovascular thrombectomy 1
• CTA can be performed at the time of initial brain CT without delay for patients with suspected large vessel occlusion 1
• For patients presenting within 6 hours with clear large vessel occlusion signs (e.g., hyperdense middle cerebral artery sign with new atrial fibrillation), proceeding directly to catheter angiography after non-contrast CT may be preferable to enable immediate conversion to thrombectomy 1

Perfusion Imaging - Time-Dependent

• CT perfusion (CTP) is NOT necessary within the first 6 hours for clear thrombectomy candidates, and obtaining it may cause harmful delays 1
• CTP becomes essential for the 6-24 hour window to determine eligibility for endovascular therapy in anterior circulation strokes with confirmed large vessel occlusion 1
• CTP offers faster diagnosis than MR perfusion in most settings, making it the preferred modality for extended window evaluation 1

Cardiac Evaluation

Electrocardiography

• 12-lead ECG immediately without delaying acute stroke treatment to assess cardiac rhythm and identify atrial fibrillation or acute coronary syndrome 1, 2, 3
• Continuous cardiac monitoring for at least 24-72 hours to detect paroxysmal atrial fibrillation and arrhythmias 2, 3

Echocardiography

• Transthoracic echocardiography within 24 hours if no cardiac source identified on initial evaluation 3
• Consider transesophageal echocardiography for suspected cardiac embolic source, particularly in younger patients or when transthoracic study is non-diagnostic 1

Laboratory Investigations

Immediate Bloodwork

• Complete blood count with platelets, comprehensive metabolic panel (electrolytes, renal function, glucose), coagulation studies (PT/INR, aPTT), and troponin 1, 2, 3
• These tests should be obtained immediately but never delay imaging for laboratory results except coagulation studies if thrombolysis is being considered 3

Subsequent Laboratory Tests

• Lipid profile (fasting or non-fasting) and hemoglobin A1c or 75g oral glucose tolerance test for diabetes screening 1, 3
• For patients ≥50 years with suspected giant cell arteritis symptoms (headache, scalp tenderness, jaw claudication, temporal tenderness): immediate erythrocyte sedimentation rate, C-reactive protein, and complete blood count 1

Carotid and Vertebral Artery Imaging

Extracranial Vascular Assessment

• Doppler ultrasound of carotid and vertebral arteries within 24-48 hours for patients with TIA or minor stroke who are candidates for carotid endarterectomy or stenting 1, 3
• CTA or MRA of cervical vessels is recommended for comprehensive evaluation of extracranial and intracranial circulation, particularly if significant symptomatic carotid stenosis is suspected 1, 3
• Carotid ultrasound is sensitive and specific for detecting extracranial vascular disease but does not provide information needed for acute thrombolysis or thrombectomy decisions 1

Neurological Assessment and Monitoring

Initial Evaluation

• Neurological evaluation by stroke-experienced physician within 30 minutes of admission, available 24/7 2, 3
• NIH Stroke Scale (NIHSS) assessment immediately and repeated multiple times daily to detect clinical deterioration 3
• Document exact time of symptom onset or last known normal, which is crucial for determining eligibility for reperfusion therapies 2

Post-Treatment Monitoring

• For thrombolysis candidates: neurological checks and vital signs every 15 minutes for 2 hours, then every 30 minutes for 6 hours, then hourly for 16 hours 3
• Monitor temperature every 4 hours for first 48 hours and treat fever >37.5°C with acetaminophen 2, 3

Timing-Based Workup Algorithms

Hyperacute Presentation (<6 Hours)

• Non-contrast CT head + CTA arch-to-vertex immediately 1, 3
• Do not obtain CTP if clear large vessel occlusion and patient is obvious thrombectomy candidate - proceed directly to intervention 1
• 12-lead ECG and laboratory studies without delaying imaging 3

Extended Window (6-24 Hours)

• Non-contrast CT head + CTA + CT perfusion required to determine eligibility for endovascular therapy 1
• MR perfusion with DWI is acceptable alternative but CTP is typically faster 1

Subacute Presentation (24 Hours to 2 Weeks)

• Brain imaging (CT or MRI) and vascular imaging (CTA or MRA from aortic arch to vertex) within timeframes based on risk stratification 1
• High-risk patients (unilateral weakness, language/speech disturbance): comprehensive evaluation within 24 hours 1
• Moderate-risk patients (sensory symptoms, monocular vision loss, ataxia without motor/language symptoms): evaluation within 2 weeks 1

Additional Investigations for Cryptogenic Stroke

When Standard Workup is Negative

• Extended cardiac monitoring (>24 hours) for patients with suspected embolic stroke of undetermined source 1
• Consider evaluation for antiphospholipid antibodies, hypercoagulable states, and autoimmune conditions in younger patients or when no clear etiology identified 1
• Susac syndrome workup (hearing loss, CNS lesions, multiple BRAOs) should be considered in younger patients with multiple or recurrent branch retinal artery occlusions 1
• Evaluation for carotid dissection in patients with neck or face pain following recent trauma 1

Critical Pitfalls to Avoid

• Never administer aspirin or antithrombotics before brain imaging rules out hemorrhage 3
• Never delay door-to-imaging time beyond 30 minutes or door-to-needle time beyond 60 minutes (target ≤30 minutes for thrombolysis candidates) 3
• Do not obtain contrast-enhanced CT as initial study 3
• Avoid obtaining CTP in obvious thrombectomy candidates within 6 hours as this causes harmful delays 1
• The NIHSS score correlates poorly with presence of large vessel occlusion, so do not use it alone to determine need for vascular imaging 1

Admission and Ongoing Care

• Admit to dedicated stroke unit with monitored beds for at least 24 hours (except stroke mimics) 2
• Implement venous thromboembolism prophylaxis with intermittent pneumatic compression devices within 24 hours for immobile patients 2
• Keep patient NPO until swallowing assessment completed 3
• Begin frequent, brief, out-of-bed activity within 24 hours if no contraindications 2