Introduction to Stroke CVA

Stroke is a neurological disorder characterized by blockage of blood vessels. Clots form in the brain and interrupt blood flow, clogging arteries and causing blood vessels to break, leading to bleeding. 

CVA (stroke) can cause paralysis, speech loss, or vision and hearing. They are one of the leading causes of death and disability in the United States, and are also a leading cause of long-term disability among adults1. This can occur at any age but is most common in people older than sixty-five.

Treatment for CVA depends on the severity and location in the brain. For example, some strokes require only treatment with medications, while others may require surgery or procedures to remove blood clots from narrowed arteries in the neck (carotid endarterectomy).

Pathophysiology of Stroke CVA

A stroke is defined as an abrupt neurological outburst caused by impaired perfusion (the passage of blood) through the blood vessels to the brain. The blood flow to the brain is managed by two internal carotids and two vertebral arteries (the circle of Willis). There are two types of strokes: TIA (transient ischaemic attack) and CVA (cerebral vascular accident). TIA temporarily limits oxygen and resolves on its own, and CVA is more permanent from a long-term lack of oxygen.

CVA vs TIA

Cerebral Vascular Accident (CVA)

Because the blood supply to the brain is interrupted, CVA is brought on by a lack of oxygen. This loss of oxygen causes long-term damage to clients. An aneurysm (a blood artery that bursts inside the brain) can also result from a stroke.

Ischemic stroke is caused by deficient blood and oxygen supply to the brain, known as embolic or thrombotic stroke. Hemorrhagic stroke is caused by bleeding or leaky blood vessels. This typically results from a blood clot, narrowed blood vessels (arteriosclerosis), or a ruptured blood vessel (aneurysm). This results in increased intracranial pressure (ICP).

Transient Ischaemic Attack (TIA)

TIA is a constriction of the blood vessels, which results in less oxygen reaching the brain and other body parts. Lack of oxygen can happen suddenly – and TIAs can come and go.

Transient TIAs have a short time frame, and Ischemic TIAs result from low oxygen.

Risk Factors and Causes

Hypertension (defined as systolic blood pressure over 140) is the number one most tested and important vital to monitor for stroke. Other risk factors and causes include:

Smoking– scars the blood vessels making them weak. 

Hyperlipidemia- (high cholesterol) narrows the blood vessels.

Uncontrolled Diabetes- causes thick sugar in the blood and puts loads of pressure on the vessels.

Increased risk from atrial fibrillation and heart valve malfunctions

Stroke Signs and Symptoms

Signs and symptoms of a stroke occur when damage occurs to an area in one hemisphere. This is known as hemispheric dominance. The left and right hemispheres of the brain are responsible for different tasks. Manifestations will depend on which hemisphere is affected and how much damage occurred. 

Signs of Impending Stroke

The signs of an impending stroke can be difficult to assess. A client experiencing a stroke can be confused, disoriented, and unable to think clearly with trouble finding words. 

Common signs of an impending stroke:

• Difficulty walking or maintaining balance
• Face and arms drooping on one side (hemiplegia)
• Double or blurry vision in one or both eyes
• Sudden nausea
• Unusual pain in the upper back or jaw
• Slurred speech

Left Hemisphere Stroke Symptoms

Left hemisphere strokes affect the side of the brain controlling functions like language and reasoning. Left hemisphere stroke clients experience:

• Right-sided weakness or paralysis and sensory impairment.
• Problems with speech and understanding language (aphasia)
• Visual problems, including the inability to see the right visual field of each eye.
• Impaired ability to do math or to organize, reason, and analyze items.

The client will most likely need rehabilitation after initial treatment.

Diagnosis criteria must include weakness or paralysis on one side of the body. This is because there are many causes for these symptoms besides a stroke—such as an infection or tumor.

Right Hemisphere Stroke Symptoms

The right hemisphere of the brain controls emotions, facial recognition, and nonverbal communication. As a result, clients with right hemisphere strokes are impacted by how they interact with others, and how well they can express themselves.

When a stroke damages the right hemisphere, clients may experience a range of symptoms that are quite different from those caused by damage to the left hemisphere, including:

• Inability to make decisions
• Difficulty speaking (aphasia) or difficulty writing (agraphia)
• Lack of empathy for others
• Vision problems, including problems seeing from the left side of each eye with Inability to recognize faces
• Difficulty with spatial reasoning
• Muscle weakness on the left side of the body.
• Hearing problems.
• Sensory changes on the left side of the body.

Right hemisphere strokes can be misdiagnosed as migraine headaches because they cause visual disturbances (migraine aura).

Stroke Assessment

The first step in caring for a client who has had a stroke is a history and physical assessment. To determine where they are experiencing their symptoms. The history includes interviewing the client with questions about the onset of symptoms. 

As a nurse, you’ll assess the level of consciousness, confusion, signs of paralysis or weakness on one side of the body – as well as slurred speech, numbness or tingling in the arms and legs, confusion, and trouble seeing out of one eye (or both).

The nurse should ask the client if they are experiencing any tingling sensations, vision problems, difficulty speaking or swallowing. A thorough history and assessment will help the health care team to determine what type of stroke the client may have experienced along with the severity of symptoms. Closed-end questions are key to a neurologic assessment as the client may not be able to answer more than “yes” or “no”.

Nursing Interventions for Stroke

Avoid

• Administering sedation meds before meals
• Completing tasks for the client (to promote independence)
• Speaking loudly to clients

Perform

• Transfers with a transfer belt (and always transfer toward the stronger side)
• Frequent neurological assessments

Provide

• Puree diet (NOT solid foods)
• Patience (especially when asking questions)
• Patient positioning (High Fowler’s – upright)

Stroke Medications

A stroke occurs when a blood vessel in the brain bursts and causes bleeding. This bleeding cuts off blood flow to part of the brain, which can cause permanent damage. The body’s natural response is to form a clot around this area to stop the bleeding, which can also cut off blood flow to other parts of the brain.

Thrombolytic drugs help dissolve these clots so that they can be removed by other medications or procedures.

Remember to implement these seizure precautions:

• Strict bed rest
• No Blood thinners
• NO Aspirin & Clopidogrel
• NO Heparin & Enoxaparin
• NO Warfarin
• NO Thrombolytics
• Limit any activity that may increase ICP
• Administer PRN stool softeners daily to prevent straining and bearing down during bowel movements

Alteplase

Mechanism of Action 

Converts plasminogen to the proteolytic enzyme plasmin, which lyses fibrin as well as fibrinogen.

Side Effects 

• Bleeding from puncture sites and wounds
• Coughing up blood
• difficulty with breathing or swallowing
• Headaches
• Increased menstrual flow or vaginal bleeding
• Nosebleeds
• Paralysis.
• Prolonged bleeding from cuts

Streptokinase

Mechanism of Action

Acts with plasminogen to produce an “activator complex,” that converts plasminogen to the proteolytic enzyme plasmin.

Side Effects

• Nausea
• Headache
• Dizziness
• Low blood pressure
• Mild fever
• Bleeding from wounds or gums
• Rash
• Itching

Stroke CVA Conclusion

When the brain is oxygen-deprived, a stroke or CVA causes long-term, irreversible damage. The most common causes of this are a blood clot, arteriosclerosis, or a damaged blood vessel (aneurysm).

Strokes can be classified as either TIAs (transient ischaemic attacks) or CVAs (cerebral vascular accidents). While TIAs restrict oxygen temporarily and resolve on their own, CVAs are more severe and result from a sustained lack of oxygen.

The nurse must be aware that the client is likely to be confused when being evaluated, especially in the early phases of recovery. Additionally, keep in mind that they can have difficulties speaking or understanding language, which could prevent them from being able to communicate successfully.

A stroke happens when a brain blood vessel bursts and starts bleeding. Blood flow to a portion of the brain is cut off by this hemorrhage, which may result in long-term harm. 

The body will naturally attempt to stop the bleeding by forming a clot around the affected location, but doing so may also block the blood supply to other areas of the brain. Thrombolytic drugs aid in dissolving these clots so that additional treatments or surgical techniques can be used to remove them.

Sources

1 https://www.cdc.gov/stroke/signs_symptoms.htm 

https://medlineplus.gov/stroke.html 

https://www.ncbi.nlm.nih.gov/books/NBK568693/