Stroke Case Study

A 66-year-old male presents to the ED with sudden slurred speech, right facial droop, and right-sided weakness that began while eating breakfast. What condition is most suspected?

Acute stroke, likely involving the left cerebral hemisphere (contralateral deficits).

Why do right-sided weakness and facial droop suggest a left-sided stroke?

Motor control is contralateral; the left brain controls the right side of the body.

This patient has hypertension, type 2 diabetes, hyperlipidemia, and a 35-pack-year smoking history. Which are modifiable vs non-modifiable stroke risk factors?

• Modifiable: Hypertension, diabetes, smoking, hyperlipidemia

• Non-modifiable: Age, sex, genetics

When a patient presents with suspected stroke, what critical time-based question must be asked immediately?

“When was the patient last known well?”

Why is “last known well” time critical in stroke care?

It determines eligibility for tPA, which has a strict treatment window.

What focused neurologic tool is used to quantify stroke severity?

NIH Stroke Scale (NIHSS)

This patient has an NIHSS score of 12. What does this indicate?

Moderate stroke severity

What is the most important diagnostic test to confirm stroke type?

Non-contrast CT scan of the head

Why must the CT be non-contrast?

To rule out hemorrhage before giving tPA.

The CT shows no hemorrhage but early signs of left MCA infarct. What type of stroke is this?

Acute ischemic stroke

Why is an EKG obtained during stroke workup?

To assess for atrial fibrillation or cardiac sources of emboli.

Is this patient a candidate for tPA? Why?

Yes, because:

• Ischemic stroke confirmed

• Symptom onset within time window

• No hemorrhage on CT

• Labs within acceptable limits

What is the time window for IV tPA administration?

• 3 hours standard

• Up to 4.5 hours for select patients

What is the goal door-to-needle time for tPA?

≤ 60 minutes

What lab values must be acceptable before giving tPA?

• Platelets > 100,000

• INR ≤ 1.7

• Glucose not severely abnormal

Why must blood glucose be checked before tPA?

Hypoglycemia can mimic stroke symptoms.

What is the standard dosing formula for alteplase (tPA)?

0.9 mg/kg (max 90 mg)

A patient weighs 80 kg. What is the total tPA dose?

0.9 × 80 = 72 mg

How is the total tPA dose administered?

• 10% IV bolus

• 90% IV infusion over 60 minutes

For a total dose of 72 mg, what is the bolus dose?

7.2 mg

For a total dose of 72 mg, what is the infusion dose?

64.8 mg over 60 minutes

If alteplase is supplied as 100 mg in 100 mL, what is the infusion rate for 64.8 mg?

64.8 mL/hr

What are key post-tPA administration considerations?

• No anticoagulants or antiplatelets for 24 hours

• Avoid invasive procedures

• Strict BP control

• Frequent neuro checks

What blood pressure must be maintained after tPA?

< 180/105 mmHg

Why is BP control critical after tPA?

Hypertension increases the risk of intracranial hemorrhage.

What neurologic changes after tPA are most concerning?

• Sudden headache

• Nausea/vomiting

• ↓ level of consciousness

• New neurologic deficits

(→ suspect intracranial bleed)

How often are neuro checks performed after tPA?

• Every 15 min × 2 hrs

• Every 30 min × 6 hrs

• Every hour × 16 hrs

A patient presents with slurred speech and right-sided weakness. What is the priority diagnostic test?

A. MRI with contrast
B. EEG
C. Non-contrast CT scan
D. Carotid ultrasound

C
Rationale: A non-contrast CT rapidly distinguishes ischemic vs hemorrhagic stroke.

Which finding would exclude a patient from receiving tPA?

A. BP 165/95
B. Platelets 150,000
C. INR 1.0
D. Active intracranial hemorrhage

D
Rationale: Hemorrhage is an absolute contraindication to tPA.

A patient weighs 70 kg. How much alteplase should be administered total?

A. 49 mg
B. 63 mg
C. 70 mg
D. 90 mg

B
Rationale: 0.9 mg/kg × 70 kg = 63 mg.

For a 63 mg total tPA dose, how much is given as the IV bolus?

A. 3 mg
B. 6.3 mg
C. 56.7 mg
D. 63 mg

B
Rationale: 10% of total dose = 6.3 mg bolus.

Which assessment finding after tPA requires immediate action?

A. Mild headache
B. BP 172/98
C. Sudden vomiting and ↓ LOC
D. Fatigue

C
Rationale: These are signs of possible intracranial hemorrhage.

Why are antiplatelet medications withheld for 24 hours after tPA?

A. They decrease tPA effectiveness
B. They cause hypotension
C. They increase bleeding risk
D. They alter glucose levels

C
Rationale: Combining antiplatelets with tPA increases hemorrhage risk.