The Acute Stroke Workup: Time is Brain, But What Comes Next?

The Acute Stroke Workup: Time is Brain, But What Comes Next?

Time is Brain. But What Actually Happens After That?

You've heard the phrase a thousand times in med school. "Time is brain." It's drilled into you during your neurology rotation, scrawled on whiteboards in the ED, muttered by attendings when a code stroke rolls in. But what does it actually mean for your workflow? How do you go from "stroke alert" to definitive treatment in a way that doesn't compromise patient safety?

This is the practical guide I wish I had during my first month on call. Not the textbook algorithm, but the real-world decision tree that separates good stroke care from great stroke care.

The Numbers: Why This Matters

Stroke remains a global health catastrophe. According to the 2021 Global Burden of Disease study, there were 11.9 million new strokes worldwide last year. That number is projected to rise by 81% by 2050. In the United States alone, about 795,000 people have a stroke each year, and it remains the second leading cause of death and the third leading cause of disability combined.

But here's what really sticks with me: one in four adults over 25 will experience a stroke in their lifetime. That's not abstract statistics. That's your neighbor, your patient, maybe even you someday.

The good news? About 84% of strokes are attributable to modifiable risk factors. Hypertension, smoking, atrial fibrillation, diabetes, obesity. We can prevent a lot of this. But when prevention fails, the acute workup becomes critical.

The First 10 Minutes: Stabilization and Assessment

When the stroke alert comes in, your first priority isn't imaging. It's stabilization. ABCs first. Airway, breathing, circulation. Then get an IV, grab vital signs, check a point-of-care glucose.

Why glucose? Because hypoglycemia can mimic stroke. I've seen it happen. A patient comes in with right-sided weakness, looks like a classic left MCA stroke, and turns out to be blood sugar of 42. The workup stops there. The fix is that simple.

Get a 12-lead ECG early. Atrial fibrillation is the most common cardiac cause of ischemic stroke, and catching it in the ED changes your entire management plan. Don't wait for cardiology to do it later.

Activate the stroke team now. Not after you've finished your assessment. Now. Because every minute counts, and you need specialists ready when imaging results come back.

The NIHSS: Your Best Friend in Stroke

The National Institutes of Health Stroke Scale is a 15-item neurological examination that scores from 0 to 42. It assesses level of consciousness, gaze, visual fields, facial palsy, motor function in the arms and legs, ataxia, sensory function, language, dysarthria, and neglect.

Here's how to interpret it:

• 0 points: No stroke symptoms
• 1-4 points: Minor stroke
• 5-15 points: Moderate stroke
• 16-20 points: Moderate to severe stroke
• 21-42 points: Severe stroke

But here's the clinical pearl that actually matters: score what the patient does, not what you think they can do. If they can't follow commands because they're confused, don't give them partial credit on the motor exam. Score based on observable function.

I've seen residents fudge scores to make the picture look better or worse than it is. Don't do this. The NIHSS guides treatment decisions. An inaccurate score could deny a patient thrombolysis or expose them to unnecessary risk.

Imaging: The Critical Decision Point

Non-contrast CT of the head is your first imaging study. Always. No exceptions. The goal is simple: rule out hemorrhage before giving thrombolytics.

Reading the NCCT

Hemorrhagic stroke appears as a hyperdense (bright white) area within the brain parenchyma. Fresh blood has high attenuation on CT. Look for surrounding edema, mass effect compressing the ventricles, and the "swirl sign" which suggests ongoing bleeding and carries a worse prognosis.

Ischemic stroke is trickier. In the first few hours, the CT might look completely normal. That doesn't mean there's no stroke. Look for subtle signs:

• Hyperdense vessel sign: A bright middle cerebral artery or other major vessel indicating acute thrombus
• Loss of gray-white matter differentiation: The boundary between cortex and white matter blurs
• Insular ribbon sign loss: The insular cortex loses its normal clarity
• Sulcal effacement: Brain swelling flattens the sulci

Pro tip: Use "stroke windows" on your CT scanner. Adjust the width to 30 HU and center to 35 HU. This significantly improves detection of early ischemic changes that standard windows might miss.

CTA: The Next Step

Once you've ruled out hemorrhage, do a CT angiogram. This isn't optional. You need to know if there's a large vessel occlusion because that determines whether the patient needs thrombectomy.

CTA visualizes the cerebral vessels in detail. It identifies the location and extent of occlusions, assesses collateral blood flow (which is prognostically important), and can detect underlying carotid disease or aneurysms.

CT Perfusion: When Time Gets Complicated

If the patient presents 4.5 to 24 hours after symptom onset, or if it's a wake-up stroke with unclear onset time, you need CT perfusion. This advanced imaging identifies salvageable brain tissue (the penumbra) versus infarct core.

The concept is simple: not all the brain tissue supplied by the occluded artery is dead yet. Some is ischemic but still viable. If you can restore blood flow to that tissue, you save function. CTP helps you identify those patients who will benefit from extended window treatment.

Treatment: The Decision Tree

Intravenous Thrombolysis

The 2026 AHA/ASA guidelines endorse both tenecteplase and alteplase for intravenous thrombolysis within 4.5 hours of symptom onset.

Tenecteplase is now preferred in most centers. Here's why:

• Dose: 0.25 mg/kg (maximum 25 mg) as a single IV bolus over 5 seconds
• Non-inferior to alteplase in multiple randomized trials
• Potentially superior for large vessel occlusions
• Simpler administration: one push instead of a 60-minute infusion

Alteplase remains an acceptable alternative when tenecteplase is unavailable:

• Dose: 0.9 mg/kg (maximum 90 mg), with 10% as initial bolus, rest infused over 60 minutes
• Time window: Within 4.5 hours of symptom onset

Extended window thrombolysis (4.5 to 9 hours) may be considered for wake-up strokes or unclear onset times if perfusion imaging shows salvageable penumbra. The TRACE-3 trial demonstrated tenecteplase efficacy up to 24 hours in select patients with advanced imaging guidance.

Endovascular Thrombectomy

This is where stroke care has undergone a paradigm shift. Mechanical thrombectomy for large vessel occlusion is now standard of care, and the time window has expanded dramatically.

Standard window (0-6 hours):

• Strongly recommended for anterior circulation LVO (Class I, Level A evidence)
• Door-to-groin time should be under 90 minutes when possible

Extended window (6-16 hours):

• The DEFUSE 3 trial changed everything here
• Inclusion criteria: infarct volume less than 70 mL, mismatch ratio greater than or equal to 1.8, penumbra volume greater than or equal to 15 mL
• Functional independence: 45% with thrombectomy vs 17% with medical management alone

Late window (6-24 hours):

• The DAWN trial selected patients based on clinical-core mismatch
• A 10% absolute reduction in 90-day mortality compared to medical management
• The RESILIENT-Extend trial (2024) demonstrated benefit even in the 8-24 hour window using simplified imaging criteria

Beyond 24 hours:

• Emerging evidence suggests similar outcomes to treatment within 24 hours
• Further randomized controlled trials needed for definitive conclusions

Recent Advances: What's New in 2024-2025

The field of stroke care is evolving rapidly. Here are the advances that will shape practice in the coming years:

AI-assisted diagnostics: Automated detection of large vessel occlusions on CTA is becoming reality. AI algorithms can identify LVOs faster than human readers in some cases, potentially reducing door-to-treatment time.

Direct-to-angiography protocols: Some centers are bypassing the CT scanner entirely for patients with clear stroke symptoms and known last-known-well times. This workflow optimization minimizes delays but requires careful patient selection.

Device-based neurostimulation: The Vivistim Paired VNS System received FDA approval for improving hand and arm function in chronic stroke patients when combined with rehabilitation. This is just the beginning of neuromodulation approaches to stroke recovery.

Stem cell therapy and exosomes: Early trials are showing promise in regenerating damaged brain tissue. We're not there yet for routine clinical use, but the trajectory is encouraging.

Clinical Pearls: What I Wish Someone Had Told Me

1. Door-to-needle time should be under 45 minutes. Every minute counts. Organize your workflow to make this happen.
2. Always establish last known well time first. This drives every treatment decision. Ask the patient, ask family, ask EMS. Get it documented immediately.
3. NCCT rules out hemorrhage before thrombolytics. Never skip this step. I can't stress this enough. Giving tPA to a hemorrhagic stroke patient is catastrophic.
4. CTA is standard of care. Don't just do NCCT. Look for large vessel occlusions that might need thrombectomy.
5. Wake-up strokes are not excluded from treatment. Use the midpoint of sleep as your time reference. Perfusion imaging is critical for decision-making.
6. Tenecteplase is first-line over alteplase. Simpler administration, non-inferior efficacy, possibly superior for LVO.
7. Think beyond 6 hours for thrombectomy. With proper imaging selection, many patients still benefit from mechanical intervention in the extended window.
8. Call neurology early. Don't wait for the full workup to be complete. Early consultation improves outcomes.
9. Blood pressure management matters: Before tPA: less than 185/110 mmHg. After tPA: less than 180/105 mmHg for 24 hours. Permissive hypertension up to 220/120 in non-tPA candidates.
10. Start antiplatelets within 24-48 hours after ruling out hemorrhage and giving tPA (if administered).

The Bottom Line

Acute stroke management has come a long way. We've expanded treatment windows, improved imaging capabilities, and refined our understanding of which patients benefit from which interventions. But the fundamentals remain: rapid assessment, appropriate imaging, and timely treatment.

"Time is brain" isn't just a catchy phrase. It's a call to action. Every minute of delay costs you 1.9 million neurons. That's not abstract. That's function lost. Memory, language, movement, cognition. All gone in an instant.

So when that stroke alert comes in, move fast. Think clearly. And remember: you're not just treating a stroke. You're saving someone's life, their independence, their ability to hold their grandchildren, to walk their dog, to write their memoirs. That's why we do this.

The workup is systematic. The treatment is time-critical. The outcome depends on how well you execute in those first hours. Make them count.