A 58-year-old man with hypertension and diabetes presents to the emergency department 2.5 hours after acute onset of right-sided weakness and speech difficulty. On examination, he has right facial droop, right arm drift, and expressive aphasia. CT head (non-contrast) shows no hyperdensity. What is the most appropriate next step in management?

Explanation

## Clinical Context This patient presents with acute ischemic stroke symptoms within the 4.5-hour thrombolytic window. The non-contrast CT head excludes hemorrhage, which is the only absolute contraindication to thrombolysis in acute ischemic stroke. ## Thrombolytic Window & Eligibility **Key Point:** Intravenous alteplase (tPA) is indicated for acute ischemic stroke within 4.5 hours of symptom onset, provided hemorrhage is excluded on non-contrast CT. **High-Yield:** The time window for IV tPA is: - **0–3 hours:** Standard indication (Class I) - **3–4.5 hours:** Extended window for selected patients without contraindications (Class IIb) This patient is at 2.5 hours, well within the standard window. ## Why Immediate tPA Administration? 1. **Non-contrast CT excludes hemorrhage** — the only absolute contraindication 2. **No mention of contraindications** (recent surgery, coagulopathy, severe hypertension >185/110 uncontrolled) 3. **Time is brain** — every minute of delay increases infarct volume and worsens outcome 4. **CT angiography is NOT required before tPA** — it delays treatment and is reserved for thrombectomy candidacy assessment (which requires advanced imaging but does not delay tPA) ## Management Algorithm ```mermaid flowchart TD A[Acute stroke symptoms]:::outcome --> B{Time since onset?}:::decision B -->|< 4.5 hrs| C[Non-contrast CT]:::action C --> D{Hemorrhage?}:::decision D -->|Yes| E[Exclude tPA, manage ICH]:::urgent D -->|No| F{Contraindications to tPA?}:::decision F -->|Yes| G[Thrombectomy evaluation if < 24 hrs]:::action F -->|No| H[IV alteplase immediately]:::action H --> I[Thrombectomy if large vessel occlusion]:::action B -->|> 4.5 hrs| J[Thrombectomy if < 24 hrs + perfusion mismatch]:::action ``` **Clinical Pearl:** Waiting for MRI or CT angiography before tPA administration in the 0–3 hour window is a major cause of treatment delay and poor outcomes. tPA should be given as soon as hemorrhage is excluded. [cite:Harrison 21e Ch 370]