What is the management approach for a patient with acute left-sided arm and leg weakness?

Management of Acute Left-Sided Arm and Leg Weakness

A patient with acute left-sided arm and leg weakness should be immediately transported to an emergency department with advanced stroke capabilities, as this presentation indicates VERY HIGH risk for stroke and requires urgent brain imaging (CT or MRI) and vascular imaging (CTA or MRA from aortic arch to vertex) within 24 hours. 1

Immediate Clinical Recognition

The combination of unilateral arm and leg weakness represents a cardinal stroke symptom pattern that demands emergency evaluation:

• Patients presenting within 48 hours of symptom onset with unilateral weakness (face, arm, and/or leg) are classified as VERY HIGH risk for stroke or recurrent stroke 1
• The historical risk of stroke after TIA/minor stroke can be as high as 10% within the first week, with the highest risk concentrated in the first 48 hours 1
• Left-sided weakness specifically suggests right hemisphere involvement, typically affecting the right middle cerebral artery territory or its branches 2

Emergency Department Priorities (First 24 Hours)

Immediate Actions Upon Arrival

• The patient must be sent immediately to an ED with capacity for advanced stroke care, including on-site brain and vascular imaging and ideally access to thrombolysis (tPA) and endovascular therapy 1
• Establish the exact time of symptom onset (when patient was last at baseline) to determine eligibility for acute interventions 3
• Perform rapid stroke screening using FAST assessment (Face, Arm, Speech, Time) 3
• Check capillary blood glucose immediately to exclude hypoglycemia as a stroke mimic 3

Urgent Neuroimaging (Without Delay)

• Urgent brain imaging with non-contrast CT or MRI must be completed as soon as possible within 24 hours to exclude hemorrhage and confirm ischemia 1, 3
• Non-invasive vascular imaging (CTA or MRA from aortic arch to vertex) should be performed to assess for large vessel occlusion and identify the anatomic level of any arterial stenosis or occlusion 1, 4
• Carotid imaging is essential to identify symptomatic carotid stenosis that may require urgent revascularization 4, 3

Essential Laboratory Investigations

• An electrocardiogram (ECG) should be completed without delay to assess for atrial fibrillation or other cardiac arrhythmias 1, 4, 3
• Complete blood count, serum electrolytes, renal function, coagulation studies (aPTT, INR), and glucose should be obtained 4, 3
• Troponin levels help identify concurrent cardiac pathology 3

Risk Stratification and Timing

The urgency of evaluation depends critically on symptom onset timing:

• Within 48 hours of onset: VERY HIGH risk—requires immediate ED transfer with stroke capabilities and consideration for acute reperfusion therapies (tPA, thrombectomy) 1, 3
• Between 48 hours and 2 weeks: HIGH risk—requires comprehensive evaluation by stroke specialist within 24 hours of first healthcare contact 1, 3
• Beyond 2 weeks: MODERATE risk—still requires neurologist evaluation but with lower urgency (within one month) 3

Acute Treatment Considerations

If imaging confirms acute ischemic stroke without hemorrhage:

• Intravenous alteplase (tPA) should be considered if the patient presents within the appropriate time window and has no contraindications 2, 5
• Mechanical thrombectomy should be considered for large vessel occlusions, particularly middle cerebral artery (MCA) M1 occlusions 2
• The combination of tPA followed by thrombectomy has been successfully used in cases of massive MCA stroke 2

Cardiac Evaluation

• Echocardiography (transthoracic and/or transesophageal) should be considered if a cardioembolic source is suspected 4
• Extended cardiac monitoring should be performed if paroxysmal atrial fibrillation is suspected, as this is a common stroke mechanism 4

Secondary Prevention Initiation

Once acute stroke is confirmed and hemorrhage excluded:

• Antiplatelet therapy should be initiated promptly for secondary stroke prevention 1
• If significant carotid stenosis (≥50% symptomatic) is identified, early carotid revascularization (endarterectomy or stenting) should be considered to prevent recurrent stroke 1, 4
• Risk factor modification must begin immediately, including blood pressure control, diabetes management, smoking cessation, and lipid management with LDL-C target <1.4 mmol/L (<55 mg/dL) 1, 4

Critical Pitfalls to Avoid

Do not delay imaging or specialist consultation based on symptom severity—even minor or transient weakness carries substantial stroke risk 1. The recent EXPRESS study demonstrated that 90-day stroke recurrence risk was 2.1% with immediate access to TIA clinic versus 10.3% without immediate access 1.

Do not assume peripheral causes—unilateral arm and leg weakness together strongly suggests central (brain) pathology rather than peripheral nerve or spinal cord lesions 4. The exception would be cervical myelopathy, but this typically presents with bilateral symptoms and sensory level 6.

Do not overlook unusual stroke mechanisms—while most strokes are atherothrombotic or cardioembolic, rare causes include arterial dissection, paradoxical embolism, or even vascular tumors that can mimic hemorrhage 7, 5.

Follow-Up Surveillance

• Patients with confirmed TIA or minor stroke require close follow-up, ideally at a dedicated stroke prevention clinic 1
• Repeat vascular imaging may be necessary to monitor for disease progression or restenosis after revascularization 1
• Patient education about stroke warning signs and when to seek emergency care is essential for early recognition of recurrent events 1