Cerebrovascular Disorders and Stroke

• Cerebrovascular disorders encompass a variety of conditions that affect the blood vessels of the brain, potentially leading to significant neurological deficits

Stroke (Brain Attack)

• Stroke is the primary cerebrovascular disorder, characterized by a sudden loss of brain function resulting from disruption of the blood supply to a part of the brain
• Ischemic stroke results from inadequate blood flow to the brain, while hemorrhagic stroke occurs from bleeding into the brain tissue or subarachnoid space
• Stroke is a leading cause of long-term disability and the fifth leading cause of death in the United States
• Risk factors include hypertension, hyperlipidemia, diabetes, smoking, obesity, and atrial fibrillation
• Non-modifiable risk factors include age, sex, race, and family history
• Transient Ischemic Attack (TIA) are temporary episodes of neurologic dysfunction caused by brief interruption of cerebral blood flow
• TIA serves as a warning sign of an impending stroke

Pathophysiology of Ischemic Stroke

• Ischemic strokes are classified as thrombotic or embolic
• Thrombotic strokes result from clot formation in a blood vessel supplying the brain
• Embolic strokes occur when an embolus lodges in a cerebral artery, leading to infarction and edema of the area supplied by the vessel
• The extent of the stroke depends on the area of the brain affected and the availability of collateral circulation

Pathophysiology of Hemorrhagic Stroke

• Hemorrhagic strokes result from bleeding into the brain tissue (intracerebral hemorrhage) or into the subarachnoid space (subarachnoid hemorrhage)
• Intracerebral hemorrhage is commonly caused by hypertension, ruptured aneurysms, or arteriovenous malformations (AVMs)
• Subarachnoid hemorrhage is frequently caused by rupture of a cerebral aneurysm

Clinical Manifestations of Stroke

• Clinical manifestations vary depending on the location and extent of the brain damage
• Motor deficits may include hemiparesis (weakness on one side of the body) or hemiplegia (paralysis on one side of the body)
• Sensory deficits involve impairment of touch, pain, temperature, and proprioception
• Communication deficits may include aphasia (difficulty with speech)
• Cognitive deficits may include memory loss, impaired judgment, and decreased attention span
• Perceptual disturbances may include visual field deficits or neglect syndrome

Diagnostic Studies

• Computed tomography (CT) scan is typically the first diagnostic test performed to differentiate between ischemic and hemorrhagic stroke
• Magnetic resonance imaging (MRI) provides more detailed information about the extent and location of the stroke
• Cerebral angiography identifies the source of the stroke
• Transcranial Doppler ultrasonography evaluates cerebral blood flow
• Electrocardiogram (ECG) and echocardiography may be performed to identify cardiac sources of emboli

Collaborative Care for Ischemic Stroke

• Rapid recognition and treatment are crucial to minimize brain damage
• Thrombolytic therapy with tissue plasminogen activator (tPA) is the standard treatment for acute ischemic stroke
• tPA must be administered within 3 to 4.5 hours of symptom onset
• Endovascular procedures, such as mechanical thrombectomy, may be used to remove clots from large cerebral vessels
• Antiplatelet medications (e.g., aspirin) are used to prevent secondary stroke

Collaborative Care for Hemorrhagic Stroke

• Management focuses on controlling bleeding and preventing increased intracranial pressure (ICP)
• Surgical interventions may be necessary to evacuate hematomas or repair aneurysms or AVMs
• Medications, such as antihypertensives and anti-seizure drugs, may be used to manage blood pressure and prevent seizures
• Management of vasospasm: Vasospasm is a narrowing of blood vessels in the brain that can occur after a subarachnoid hemorrhage. It reduces blood flow to the brain, potentially causing ischemia (lack of oxygen) and further brain damage. Nimodipine is often prescribed to prevent or treat vasospasm.

Nursing Assessment

• A comprehensive neurologic assessment includes evaluation of level of consciousness, motor strength, sensory function, cranial nerve function, and reflexes
• Monitor vital signs and assess for signs of increasing ICP, such as decreased level of consciousness, headache, vomiting, and pupillary changes
• Assess the patient's ability to communicate and swallow
• Assess the patient's skin integrity and risk for pressure ulcers

Nursing Diagnoses

• Impaired physical mobility
• Impaired verbal communication
• Impaired swallowing
• Unilateral neglect
• Risk for aspiration
• Risk for impaired skin integrity
• Risk for constipation

Nursing Interventions

• Position the patient to prevent aspiration and promote venous drainage
• Provide skin care to prevent pressure ulcers
• Implement measures to prevent deep vein thrombosis (DVT) and pulmonary embolism
• Establish bowel and bladder programs to promote regular elimination
• Provide emotional support and education to the patient and family

Rehabilitation

• Rehabilitation begins as soon as the patient is medically stable
• Physical therapy focuses on improving motor function, strength, and balance
• Occupational therapy focuses on improving activities of daily living (ADLs) and fine motor skills
• Speech therapy focuses on improving communication and swallowing
• Psychological support addresses emotional and cognitive challenges

Home Care

• Home care focuses on maximizing the patient's independence and quality of life
• Patient and family education includes information about medication management, nutrition, and safety precautions
• Referrals to community resources may be necessary to provide ongoing support
• Regular follow-up with healthcare providers is essential to monitor progress and prevent complications

Aneurysms

• Aneurysms involve an outpouching or sac-like dilation of a blood vessel wall
• Cerebral aneurysms often occur in the Circle of Willis
• Rupture of an aneurysm can result in subarachnoid hemorrhage
• Diagnosis is typically made by CT angiography or magnetic resonance angiography (MRA)
• Surgical clipping or endovascular coiling may be used to prevent rupture

Arteriovenous Malformations (AVMs)

• AVMs are congenital abnormalities consisting of tangled arteries and veins without an intervening capillary bed
• AVMs can rupture and cause intracerebral hemorrhage or subarachnoid hemorrhage
• Symptoms may include headaches, seizures, and neurologic deficits
• Treatment options include surgical resection, stereotactic radiosurgery, or endovascular embolization

Nursing Management of Aneurysms and AVMs

• Monitor neurologic status and vital signs
• Implement seizure precautions
• Manage pain and anxiety
• Prepare the patient for surgical or endovascular procedures
• Provide education about the condition, treatment options, and potential complications