Ischemic Stroke

Key considerations: Large vessel occlusion (LVO) amenable to thrombectomy, Posterior circulation stroke (basilar artery), Hemorrhagic stroke mimicking ischemic

Cannot miss

Large vessel occlusion (LVO) amenable to thrombectomy
Posterior circulation stroke (basilar artery)
Hemorrhagic stroke mimicking ischemic
Stroke mimic (hypoglycemia, Todd paralysis, conversion disorder)

Likely diagnoses

Anterior circulation ischemic stroke
Posterior circulation ischemic stroke
Lacunar stroke
TIA

Red flags

Acute onset focal neurological deficit
NIHSS ≥6 (consider LVO)
NIHSS ≥10 (high probability LVO)
Last known well <24h (thrombectomy window)
Posterior circulation signs (vertigo, diplopia, ataxia, altered consciousness)

Workup

history: Last known well time (critical for treatment decisions); Symptom onset and progression; Anticoagulant use; Recent surgery or trauma; exam: NIHSS score; Neurological exam; BP in both arms; Cardiac exam (irregularity → AF); labs: Fingerstick glucose (BEFORE CT — do not delay); CBC, BMP, coagulation studies; Troponin; A1c, lipid panel (inpatient); imaging: Non-contrast CT head STAT (rule out hemorrhage); CT angiography (head and neck) for LVO detection; CT perfusion if >6h from onset (identifies salvageable penumbra); MRI DWI/FLAIR if diagnosis uncertain; bedside: Fingerstick glucose; ECG (atrial fibrillation detection)

Management

immediate: CT head STAT — goal door-to-CT <20 minutes; Check glucose (hypoglycemia mimics stroke); Establish IV access; NPO until swallow evaluation; general: BP management: permissive hypertension up to 220/120 unless tPA candidate (then <185/110); DVT prophylaxis; Aspirin 325mg within 24-48h (not within 24h of tPA); Statin — high-intensity (atorvastatin 80mg); specific: diagnosis: tPA Candidate (<4.5h); steps: IV alteplase 0.9mg/kg (max 90mg): 10% bolus, 90% over 60 min; BP <185/110 before and <180/105 for 24h after; No anticoagulants or antiplatelets for 24h; Follow-up CT at 24h before starting antiplatelet; diagnosis: LVO with Thrombectomy (<24h); steps: Activate neurointerventional team; CT angiography to confirm LVO; If <4.5h: give tPA AND pursue thrombectomy; Thrombectomy window extended to 24h if favorable perfusion imaging; diagnosis: Outside Treatment Window; steps: Aspirin 325mg; High-intensity statin; Stroke workup: echo, telemetry, carotid imaging; Risk factor management

Disposition

admit: All acute strokes — stroke unit preferred; TIA with high-risk features (ABCD2 ≥4); discharge: Low-risk TIA with completed workup and rapid follow-up; consults: Neurology STAT; Neurointerventional radiology if LVO; Cardiology if AF detected

Clinical pearls

Time is brain: ~1.9 million neurons die per minute of untreated LVO
tPA window: <4.5h from last known well. Thrombectomy: up to 24h with favorable perfusion
NIHSS ≥6 warrants CTA to evaluate for LVO regardless of tPA candidacy
Wake-up strokes: MRI DWI-FLAIR mismatch can identify candidates for treatment

Source and review

AHA/ASA 2019 Stroke Guidelines; Nogueira et al., NEJM 2018 (DAWN). Last reviewed: 2024-11-01