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Emergency Medicine Teaching Case

Neuro / Stroke - Attending Level

CASE PRESENTATION

Setting: Emergency Department, 08:45 AM

Chief Complaint: "My wife can't speak and her right arm is weak."

HPI

A 68-year-old right-handed woman is brought in by her husband. He states she was making breakfast and "just fine" at 08:20 AM. When he came back to the kitchen at 08:30 AM, she was slumped against the counter, unable to speak clearly, and her right arm was hanging at her side. He called 911. EMS arrived at 08:40 AM; you are receiving the patient at 08:45 AM.

Last known well: 08:20 AM - 25 minutes ago at time of arrival.

PMH / Medications

Hypertension (on lisinopril 10 mg daily)
Type 2 diabetes mellitus (on metformin; HbA1c 7.2% at last check)
Paroxysmal atrial fibrillation - on apixaban 5 mg twice daily (last dose taken last night)
No prior stroke or TIA
No prior seizures
Baseline mRS: 0 (fully independent)

Vital Signs on Arrival

BP: 192/104 mmHg
HR: 88, irregularly irregular
RR: 16
SpO2: 97% on room air
Temp: 37.1°C
Glucose (point-of-care): 138 mg/dL

SECTION 1 - INITIAL APPROACH

What do you do in the first 2 minutes?

The correct answer - activate the stroke protocol immediately and perform a rapid, targeted exam.

The moment stroke is suspected, time is the single most important variable. Every 15-minute reduction in door-to-needle time for tPA is associated with improved outcomes. The "brain is time" principle reflects that roughly 1.9 million neurons die each minute in a large vessel occlusion.

Immediate actions:

Activate stroke alert/code stroke
Establish IV access x2
Draw labs: CBC, BMP, coagulation studies (PT/INR, aPTT), type & screen, troponin
12-lead ECG
Bedside glucose (already done by EMS - 138 mg/dL, which is >50 mg/dL, so not a contraindication to tPA)
Perform NIHSS at the bedside
Order non-contrast CT head STAT - get patient to CT within 10 minutes of arrival (door-to-CT goal is <25 minutes)

Teaching point: Do NOT wait for labs before sending the patient to CT. CT takes minutes; labs should be drawn en route. The only lab you truly need before giving tPA is point-of-care glucose.

SECTION 2 - NEUROLOGICAL EXAM (NIHSS)

Findings:

NIHSS Domain	Finding	Score
1a. Level of consciousness	Alert	0
1b. LOC questions (month/age)	Answers 0/2	2
1c. LOC commands (close eyes/grip)	Performs 1/2	1
2. Best gaze	Forced gaze deviation LEFT	2
3. Visual fields	Right homonymous hemianopia	2
4. Facial palsy	Moderate - right lower face	2
5a. Left arm motor	No drift	0
5b. Right arm motor	Falls to bed in <10 sec	3
6a. Left leg motor	No drift	0
6b. Right leg motor	Mild drift, maintains >10 sec	1
7. Limb ataxia	None	0
8. Sensory	Mild-moderate right-sided loss	1
9. Best language	Severe aphasia - cannot name, follows no commands	3
10. Dysarthria	Severe - speech unintelligible	2
11. Extinction/neglect	Right visual neglect	1

Total NIHSS = 20 (Severe stroke)

What syndrome does this localize to?

Left MCA territory stroke (dominant hemisphere)

The combination of:

Right face + arm > leg weakness (corticospinal involvement)
Forced gaze deviation to the LEFT (eyes "look toward the lesion")
Global aphasia (dominant hemisphere = left in a right-hander)
Right homonymous hemianopia (optic radiation)
Right hemisensory loss

...is the classic presentation of a left middle cerebral artery (MCA) syndrome, most likely involving the proximal MCA (M1) or the internal carotid artery (ICA) terminus.

Teaching point: Gaze deviation is a key localizer. In supratentorial lesions, the eyes deviate TOWARD the lesion (the frontal eye field is destroyed, so the intact contralateral field pulls the eyes ipsilaterally). In pontine lesions, eyes deviate AWAY from the lesion (toward the hemiplegia).

SECTION 3 - IMAGING

CT Head (Non-Contrast) - Findings

Early ischemic changes present:

Hyperdense left MCA sign (clot visible in M1 segment)
Loss of the left insular ribbon
Subtle grey-white differentiation loss in left lentiform nucleus

No hemorrhage. No mass. No major established infarct.

ASPECTS Score: With involvement of lentiform nucleus + insular ribbon = ASPECTS 8 (out of 10). An ASPECTS ≥6 is required for thrombectomy eligibility.

SECTION 4 - THE TREATMENT DECISION

Should you give IV alteplase (tPA)?

This is the pivotal decision point. Walk through the checklist:

Eligibility (per 2019 AHA/ASA guidelines, as in Rosen's Emergency Medicine):

Criterion	This Patient
Age ≥18	✅ 68 years
Symptom onset (last known well) ≤3 hours	✅ ~25 minutes ago
Ischemic stroke confirmed (no hemorrhage on CT)	✅
Glucose >50 mg/dL	✅ 138 mg/dL
BP manageable to <185/110	⚠️ BP is 192/104 - needs treatment

Potential Exclusions to consider:

Factor	Assessment
On apixaban (DOAC)	⚠️ Critical decision point - see below
Diabetes + prior stroke	No prior stroke, so the 3-4.5h relative exclusion doesn't apply here
Severe stroke (NIHSS 20)	Actually SUPPORTED - even severe strokes benefit from tPA
Glucose >400	No
Active bleeding or recent surgery	No

The Anticoagulation Dilemma

She took apixaban last night. What do you do?

According to the 2019 AHA/ASA guidelines (Rosen's):

"IV alteplase should NOT be administered to patients taking direct thrombin inhibitors or direct factor Xa inhibitors unless sensitive laboratory tests such as aPTT, INR, platelet count, ECT, TT, or direct factor Xa activity assays are normal, or the patient has not taken a dose of these agents for more than 48 hours."

Options in practice:

Check anti-Xa level - if undetectable (i.e., last dose >24-48h ago or renal clearance adequate), tPA may be considered
Use andexanet alfa (reversal agent for factor Xa inhibitors) prior to tPA - though this is not standard practice and evidence is limited
Proceed directly to mechanical thrombectomy without tPA (bridging or drip-and-ship may be bypassed)

In this case: The apixaban was taken "last night" - roughly 10-12 hours ago. Anti-Xa level should be sent stat. If anti-Xa is elevated, tPA is contraindicated. The prudent path is to activate the endovascular team immediately and proceed to CT angiography (CTA) of head and neck regardless.

Blood Pressure Management Before tPA

BP is 192/104. Before tPA, target <185/110 mmHg.

Agents of choice (per Rosen's):

Labetalol 20 mg IV bolus, may repeat q10 min
Nicardipine 5-15 mg/hr IV infusion (preferred for more sustained control with less BP variability)
Clevidipine - shorter-acting calcium channel blocker, easier to titrate

Avoid: Sodium nitroprusside (raises ICP). Hydralazine (unpredictable and prolonged effect).

Once BP is below 185/110 and stable, you can administer tPA. After tPA, maintain BP <180/105 for 24 hours.

Teaching point: If BP cannot be safely lowered to <185/110, tPA is contraindicated. Do not chase BP with repeated aggressive doses - if two doses of labetalol don't work, the patient may not be a tPA candidate but should still go to thrombectomy.

SECTION 5 - CTA RESULTS

CTA Head and Neck shows:

Complete occlusion of the left M1 segment of the MCA
No significant cervical ICA stenosis
No dissection

Is this patient a candidate for mechanical thrombectomy?

Eligibility checklist (AHA/ASA, per Rosen's):

Criterion	This Patient
Prestroke mRS ≤1	✅ mRS 0
Causative occlusion of ICA or M1-MCA	✅ Left M1 occlusion
NIHSS ≥6	✅ NIHSS 20
ASPECTS ≥6	✅ ASPECTS 8
Within 6 hours of last known well	✅ <1 hour

Yes - this patient is an excellent candidate for mechanical thrombectomy.

Even if tPA is contraindicated (due to apixaban), she should go directly to the catheter suite. The goal is door-to-puncture time <90 minutes.

Teaching point: Thrombectomy benefit extends to 24 hours in selected patients (DAWN and DEFUSE-3 trials), specifically those with significant penumbra on perfusion imaging. For patients within 6 hours with proven LVO and good ASPECTS, thrombectomy is strongly indicated. The benefit for M2 occlusions is less established but directionally favorable.

SECTION 6 - DISPOSITION AND MANAGEMENT BUNDLE

Immediate disposition: Interventional neurology/neuroradiology suite for mechanical thrombectomy

If tPA was given (assuming anti-Xa undetectable):

tPA dose: 0.9 mg/kg IV (max 90 mg) - 10% as bolus over 1 min, remainder over 60 min
No antiplatelet or anticoagulant for 24 hours post-tPA
Admit to neuro-ICU or stroke unit for continuous BP and neuro monitoring

Post-procedure / Post-tPA monitoring:

Repeat CT head at 24 hours (before restarting anticoagulation) to rule out hemorrhagic transformation
Continuous BP monitoring - target <180/105 post-tPA
Swallow screen before any oral intake
DVT prophylaxis
Statin therapy
Cardiac monitoring for afib source confirmation
Echo to rule out LV thrombus or structural source
Resume anticoagulation (apixaban) for afib within 4-14 days depending on infarct size and hemorrhagic transformation risk

SECTION 7 - TEACHING SUMMARY

Key Learning Points

1. Time targets (door-to-X goals):

CT: <25 minutes
Needle (tPA): <60 minutes
Puncture (thrombectomy): <90 minutes

2. tPA dose: 0.9 mg/kg IV (max 90 mg); 10% bolus, 90% over 60 min

3. BP thresholds:

Pre-tPA: must bring to <185/110
Post-tPA for 24 hours: maintain <180/105
No tPA planned: treat only if BP >220/120, reduce ~15% over 24h

4. NIHSS as a decision tool:

Even severe strokes (NIHSS >22) benefit from tPA within 3 hours
NIHSS ≥6 + LVO = thrombectomy eligible
Mild, nondisabling stroke (NIHSS 0-5): tPA generally NOT recommended

5. DOAC on board = significant complication:

Check anti-Xa level (apixaban, rivaroxaban) or DTI level (dabigatran)
If level elevated: skip tPA, proceed to thrombectomy
Dabigatran reversal: idarucizumab; Factor Xa reversal: andexanet alfa

6. Mechanical thrombectomy window:

0-6h: NIHSS ≥6, M1/ICA occlusion, ASPECTS ≥6, mRS ≤1
6-24h: selected patients with salvageable penumbra (DAWN/DEFUSE-3 criteria)

7. Gaze deviation localizes lesion:

Supratentorial: eyes toward lesion (frontal eye field destroyed)
Pontine: eyes away from lesion / toward hemiplegia

8. Do NOT give nitroprusside in ischemic stroke - raises ICP via NO-mediated vasodilation

COMPLICATIONS TO WATCH

Complication	Timing	Signs	Action
Hemorrhagic transformation	Hours-days	New headache, BP spike, clinical deterioration	Stat CT; reverse if symptomatic
Malignant MCA syndrome	24-72h	Progressive edema, herniation	Neurosurgery consult; decompressive hemicraniectomy
Aspiration pneumonia	Early	Dysphagia (aphasia + facial weakness)	NPO until swallow screen
Cardiac arrhythmia	Any time	ECG changes, telemetry	Monitor; new afib requires anticoagulation plan
Hypoglycemia	Any time	Mimics stroke	Recheck glucose serially

Sources:

Rosen's Emergency Medicine: Concepts and Clinical Practice, 9e - Chapters 87, 88 (Acute Ischemic Stroke, Blood Pressure Management)
Bradley and Daroff's Neurology in Clinical Practice, 8e - Chapter 65 (Acute Stroke Treatment, tPA eligibility tables)
2019 AHA/ASA Acute Stroke Management Guidelines (as cited in Rosen's)

Want to continue with a complication scenario (e.g., the patient deteriorates 2 hours post-tPA - what now?), an alternative presentation (wake-up stroke, posterior circulation, hemorrhagic stroke), or a rapid-fire ABEM-style Q&A on the same case?

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