Study Notes on Strokes (CVA)

Overview of Strokes (CVA)

• Definition:

  • Strokes, also known as cerebrovascular accidents (CVA), occur when there is a lack of oxygen to the brain, typically due to:

  • A blood clot in a blood vessel.

  • Narrowing of blood vessels (e.g., atherosclerosis).

  • Sudden rupture of a blood vessel (e.g., aneurysm).

• Consequence:

  • Without oxygen, brain tissues begin to die, similar to any other organ lacking oxygen.

Types of Strokes

• Transient Ischemic Attack (TIA):

  • Remember as a "tiny stroke."

  • Temporary lack of oxygen (transient ischemic), occurs suddenly and resolves by itself.

  • Medical breakdown:

  • Transient: Lasts only a short time.

  • Ischemic: Lack of oxygen.

  • Attack: Happens suddenly.

• Cerebral Vascular Accident (CVA):

  • Is more serious and results in long-term damage due to permanent loss of oxygen.

• Types of Ischemic Strokes:

  • Embolic Stroke:

  • Caused by a clot that travels to the brain from another part of the body.

  • Thrombotic Stroke:

  • Caused by a clot that forms in the blood vessels of the brain.

• Hemorrhagic Stroke:

  • Involves bleeding from a ruptured blood vessel, resulting in increased intracranial pressure (ICP).

Risk Factors for Stroke

• Hypertension:

  • Significantly, hypertension (high blood pressure) over 140/90 mmHg is the number one risk factor for stroke.

  • Proper management with antihypertensive medication can reduce stroke risk by up to 50%.

• Pathophysiology:

  • Uncontrolled hypertension can damage blood vessels in the brain and lead to fragility and rupture.

• Other Causes (not frequently tested):

  • Smoking: Compromises blood vessel integrity.

  • Hyperlipidemia: High cholesterol leads to plaque buildup in arteries.

  • Uncontrolled diabetes: Increases blood viscosity, elevating pressure on blood vessels.

  • Atrial fibrillation and heart valve issues: Promote clot formation that may travel to the brain.

Key Signs and Symptoms of Stroke

• Hemiparesis (Unilateral Weakness):

  • New or sudden one-sided weakness, often indicated by arm drift.

• Rapid Assessment Acronym: F.A.S.T.:

  • F: Facial drooping or inability to smile.

  • A: Arm drift (one-sided weakness).

  • S: Speech impairment; difficulty speaking or slurred speech.

  • T: Time to call 911 and conduct a CT scan immediately (golden hour).

  • Important Note: "Time is brain," stressing the urgency of seeking medical attention.

Specific Characteristics of Hemorrhagic Strokes

• Key Sign:

  • Sudden, severe headache, often described as the "worst headache of my life."

  • This headache is much more severe than migraines and is sometimes called a silent killer because minor bleeds can go unnoticed until a major rupture occurs.

• Consequences:

  • Increases intracranial pressure (ICP) due to the accumulation of blood in the brain.

Lateralization of Stroke Effects

• Left-Sided Stroke:

  • Affects the right side of the body.

  • Results in issues with:

  • Language and logic (dysphasia).

  • Right-sided hemiparesis.

  • Neglect of the right side of the body.

  • Reading and writing problems.

• Right-Sided Stroke:

  • Affects the left side of the body.

  • Results in:

  • Impulsivity and behavioral changes (reckless behavior).

  • Left-sided hemiparesis.

  • Neglect of the left side of the body due to loss of visual perception.

• Important Nursing Note:

  • Remember to associate areas of the brain with functions:

  • Left: Language, logic.

  • Right: Creativity, impulse control.

  • Potential NCLEX question regarding family education for patients with right-sided injury emphasizes lack of impulse control and behavioral changes.

Summary

• Recognizing Stroke Symptoms:

  • Any appearance of unilateral weakness or speech impairment should be treated as a medical emergency requiring immediate attention.

  • Knowing how to act quickly is crucial for minimizing brain damage and improving the outcomes for the patient.