What is the emergency management protocol for a suspected acute ischemic stroke?

Stroke Emergency Protocol

Immediately activate EMS (9-1-1) upon recognition of stroke symptoms, perform rapid FAST screening (Face-Arm-Speech-Time), and transport directly to the nearest stroke-capable center with CT imaging—every 15-minute delay in treatment increases in-hospital mortality by 5%. 1, 2

Prehospital Recognition and Activation

Use a validated stroke screening tool (FAST scale) to identify stroke signs—any positive finding mandates immediate EMS activation and high-priority transport. 3, 1

• Screen for Face droop, Arm weakness, Speech difficulty, and document exact Time of symptom onset or last known normal time—this single data point determines all treatment eligibility 3, 2
• EMS personnel should perform a second severity assessment using a validated tool to identify potential large vessel occlusion candidates (look for aphasia, visual field defects, neglect) 3
• Patients arriving by EMS have 3-fold higher likelihood of brain imaging within 25 minutes compared to private transport 1

EMS On-Scene Management (Target ≤15-20 Minutes)

Assess and stabilize ABCs, check capillary blood glucose immediately, establish IV access, and minimize on-scene time to ≤15 minutes—do not delay transport for any intervention. 3, 1

Critical On-Scene Actions:

• Measure capillary blood glucose and treat if <60 mg/dL with IV dextrose (hypoglycemia mimics stroke and contraindicates thrombolysis) 3, 2
• Provide supplemental oxygen only if saturation <94%—avoid excessive oxygen 3, 1, 4
• Establish IV access with normal saline (avoid dextrose-containing fluids in non-hypoglycemic patients) 3, 4
• Initiate cardiac monitoring 3, 1
• Obtain blood samples for laboratory testing en route if possible 3

Blood Pressure Management:

• Do not treat hypertension in the field unless systolic BP ≥220 mmHg and only after medical command consultation 3, 2
• For potential thrombolysis candidates, maintain BP <185/110 mmHg using labetalol 10 mg IV or nicardipine infusion (5 mg/h, titrate by 2.5 mg/h every 5-15 min, max 15 mg/h) 2
• Avoid aggressive BP reduction below target—cerebral perfusion is pressure-dependent in acute stroke 2

Transport and Prenotification

Transport directly to the nearest stroke-capable center (bypassing non-stroke hospitals) and provide detailed prenotification including onset time, FAST findings, vital signs, glucose level, and anticoagulation status. 3, 1, 2

• Triage as Canadian Triage Acuity Scale (CTAS) Level 2 in most cases, Level 1 if airway/breathing/circulation compromised 3
• EMS prenotification reduces door-to-needle times by 2 minutes and is a key quality metric (target >67% prenotification rate) 1
• For patients within 6 hours of onset, specify that CT angiography will be needed to assess for large vessel occlusion 2

Emergency Department Protocol (Door-to-Imaging ≤25 Minutes)

Activate the stroke team immediately upon arrival, perform rapid neurological examination with NIHSS score, and obtain non-contrast CT within 25 minutes of arrival—this is the only definitive method to differentiate ischemic from hemorrhagic stroke. 1, 4

Immediate ED Actions (Parallel Processing):

• Perform focused neurological examination including NIHSS score 1, 4
• Obtain non-contrast CT or MRI brain within 25-30 minutes of arrival 1, 4
• Draw core laboratory panel: glucose, electrolytes, renal function, CBC with platelets, cardiac biomarkers, PT/INR, aPTT—but do not delay thrombolysis while awaiting results unless clinical suspicion of bleeding disorder, thrombocytopenia, or recent anticoagulant use 4, 2
• Obtain 12-lead ECG 1
• Perform CT angiography from aortic arch to vertex within 24 hours to identify large vessel occlusions 4

Thrombolytic Therapy Decision (Door-to-Needle ≤60 Minutes)

Administer IV alteplase (tPA) within 4.5 hours of symptom onset if no contraindications—target door-to-needle time ≤60 minutes (ideal ≤30 minutes), as treatment within 0-90 minutes provides number-needed-to-treat of 4.5 versus 14.1 for later treatment. 1, 4, 2

Absolute Requirements for IV Alteplase:

• Symptom onset <4.5 hours (or last known normal time) 1, 2
• Blood pressure <185/110 mmHg 1, 2
• No evidence of hemorrhage on CT 1
• Glucose ≥50 mg/dL 2
• No recent anticoagulation with elevated INR or use of direct oral anticoagulants 2

Post-tPA Monitoring:

• Neurological assessments every 15 minutes for 2 hours, then every 30 minutes for 6 hours, then hourly until 24 hours 1
• Delay oral aspirin until >24 hours after thrombolysis to minimize hemorrhage risk 4

Endovascular Thrombectomy Consideration

For large vessel occlusions, mechanical thrombectomy is effective within 6 hours for most patients and up to 24 hours for selected patients meeting advanced imaging criteria—do not delay transfer to comprehensive stroke center even after administering tPA. 4, 2

• "Drip-and-ship" protocol: administer IV tPA at primary stroke center, then immediately transfer to comprehensive stroke center for potential thrombectomy 3, 2
• Thrombectomy remains highly effective even after thrombolysis 2

Acute Stroke Unit Admission

Admit all stroke patients to a geographically defined stroke unit with dedicated multidisciplinary team (neurologists, specialized nurses, physiotherapists, occupational therapists, speech therapists) available 24/7. 4

• Maintain nurse-to-patient ratio of 1:2 for first 24 hours—up to 30% of patients experience neurological deterioration during this period 4
• Perform swallowing screening before any oral intake to prevent aspiration pneumonia (compulsory quality indicator) 4

Early Complications Prevention

VTE Prophylaxis:

• Subcutaneous unfractionated heparin 5,000 IU twice daily or low-molecular-weight heparin for immobilized patients 4
• Add intermittent pneumatic compression (reduces VTE and may lower mortality) 4
• Do not use anti-embolic stockings routinely 4

Aspiration Prevention:

• Place naso-enteric feeding tube within 24 hours for patients unable to swallow (preferred over PEG for first 2-3 weeks) 4
• Perform oral hygiene at least three times daily and immediately after meals 4

Early Mobilization:

• Mobilize neurologically and hemodynamically stable patients within 24 hours of admission (ideally ≤52 hours) 4

Fluid Management:

• Maintain euvolemia with isotonic normal saline—do not use volume expanders for hemodilution 4

Quality Metrics (Compulsory Indicators)

Monitor six compulsory quality indicators: door-to-needle time <60 minutes for thrombolysis patients, all acute stroke patients admitted to stroke unit, brain imaging (CT/MRI) in every suspected stroke, antiplatelet therapy at discharge for ischemic stroke, anticoagulation at discharge for atrial fibrillation patients, and swallowing screening for all patients. 4

• Target door-to-needle time ≤60 minutes in ≥50% of patients (secondary goal ≤45 minutes) 1
• Target door-to-imaging time ≤25 minutes 1
• EMS prenotification rate >67% 1

Common Pitfalls to Avoid

• Never delay transfer to obtain imaging at a non-CT facility—rapid transport supersedes any on-site intervention without imaging 2
• Do not withhold transfer for "mild" or improving symptoms—large vessel occlusions can present with fluctuating deficits 2
• Do not assume patients beyond 4.5 hours are ineligible—endovascular treatment may be offered up to 24 hours with appropriate imaging selection 2
• Avoid routine placement of indwelling urinary catheters due to infection risk 4
• Do not over-treat blood pressure in the prehospital phase unless specified thresholds are exceeded—may worsen cerebral ischemia 2