Cerebrovascular Accident (CVA) - Anesthesia Lecture

Cerebrovascular Accident (CVA)

Essential Knowledge for Anesthetic Practitioners

Department of Anesthesiology | October 26, 2025

Introduction & Epidemiology

A Cerebrovascular Accident (CVA), commonly known as a stroke, is a medical emergency characterized by the sudden interruption of blood flow to the brain, leading to neurological deficits. As anesthetists, understanding CVA is critical as we manage patients at high risk during perioperative periods.

1 in 6

People will have a stroke

87%

Ischemic strokes

13%

Hemorrhagic strokes

5.8M

Annual deaths globally

Classification of Stroke

• Ischemic Stroke (87%): Caused by thrombosis or embolism
• Hemorrhagic Stroke (13%): Includes intracerebral and subarachnoid hemorrhage
• Transient Ischemic Attack (TIA): Temporary neurological deficit without permanent damage

Key Fact

Stroke is the second leading cause of death worldwide and the leading cause of serious long-term disability. Perioperative stroke carries a mortality rate of 25-50%.

Anesthesia-Specific Considerations

Perioperative Stroke Risk Factors

• Advanced age (>65 years)
• History of previous stroke or TIA
• Atrial fibrillation
• Carotid artery stenosis
• Recent myocardial infarction
• Emergency surgery
• Prolonged surgical duration
• Cardiac and major vascular surgery

Anesthetic Goals for CVA Patients

1. Maintain cerebral perfusion pressure (CPP)
2. Avoid hypotension and hypertension
3. Prevent hypercapnia and hypoxia
4. Maintain normoglycemia
5. Avoid hyperthermia
6. Minimize cerebral metabolic demand

Critical Warning

Perioperative hypotension is a major risk factor for stroke in patients with carotid stenosis. Maintain MAP within 20% of baseline in high-risk patients.

Pathophysiology & Diagnosis

Ischemic Stroke Mechanisms

• Thrombotic: Atherosclerotic plaque rupture in cerebral arteries
• Embolic: Cardiac or arterial emboli (e.g., from AFib, endocarditis)
• Hemodynamic: Hypoperfusion in watershed areas

Hemorrhagic Stroke Causes

• Hypertension (most common)
• Cerebral amyloid angiopathy
• Arteriovenous malformations
• Aneurysm rupture (subarachnoid hemorrhage)
• Anticoagulant therapy

Diagnosis

Diagnosis is primarily clinical (sudden onset focal neurological deficit) confirmed by neuroimaging:

• Non-contrast CT: First-line for hemorrhage detection
• MRI with DWI: Gold standard for early ischemic changes
• CTA/MRA: For vascular imaging

FAST Mnemonic: Remember for stroke recognition - Face drooping, Arm weakness, Speech difficulty, Time to call emergency services.

Anesthetic Management

Preoperative Assessment

• Detailed neurological history and exam
• Assessment of stroke risk factors
• Carotid ultrasound if indicated
• Echocardiography for embolic source
• Optimization of comorbidities (HTN, DM, AFib)

Intraoperative Management

• Blood Pressure: Maintain MAP within 20% of baseline
• Ventilation: Normocapnia (PaCO₂ 35-45 mmHg)
• Oxygenation: Maintain SpO₂ >94%
• Glucose: Keep 140-180 mg/dL
• Temperature: Strict normothermia
• Positioning: Avoid neck hyperextension in carotid disease

Monitoring

• Standard ASA monitors
• Arterial line for beat-to-beat BP in high-risk cases
• Processed EEG (BIS) to assess depth of anesthesia
• Somatosensory evoked potentials (SSEPs) for high-risk procedures

Medication Considerations

Continue antihypertensives (except ACEi/ARB day of surgery). Hold anticoagulants per guidelines. Avoid vasopressors that cause cerebral vasoconstriction (e.g., phenylephrine). Prefer ephedrine or norepinephrine for hypotension.

Acute Stroke Management

Time is Brain!

Every minute, 1.9 million neurons are lost during an acute ischemic stroke. Rapid recognition and intervention are critical.

Ischemic Stroke Treatment

• IV tPA: Within 4.5 hours of symptom onset (contraindicated in hemorrhagic stroke)
• Mechanical Thrombectomy: For large vessel occlusion within 24 hours
• Supportive Care: Airway management, BP control, glucose management

Hemorrhagic Stroke Treatment

• BP control (SBP <140 mmHg)
• Reversal of anticoagulation
• Surgical evacuation for large hematomas
• ICP management if elevated

Absolute Contraindications to tPA

• Active internal bleeding
• Suspected aortic dissection
• Intracranial hemorrhage on CT
• Recent intracranial surgery
• Platelet count <100,000/mm³

Key Takeaways for Anesthetists

Prevention is paramount: Identify high-risk patients preoperatively and optimize their condition.

Hemodynamic stability: Avoid both hypotension (risk of watershed infarction) and hypertension (risk of hemorrhagic transformation).

Vigilance during emergence: Neurological assessment should begin immediately upon emergence from anesthesia.

Postoperative monitoring: High-risk patients require close neurological monitoring in PACU and beyond.

Team communication: Clear handover to PACU and ward staff regarding stroke risk and monitoring requirements.

Final Thought

"The anesthetist is the guardian of cerebral perfusion during the perioperative period. Our vigilance can prevent devastating neurological outcomes."

© 2025 Department of Anesthesiology | This educational material is for training purposes only

References: AHA/ASA Guidelines 2023, Miller's Anesthesia 9th Edition, Perioperative Stroke Consensus Statement