Surgical Therapy: Carotid Artery Stenosis

Questions and Answers

What is the primary contributing factor to stroke associated with symptomatic carotid artery stenosis?

Proximal arterial occlusion

Low levels of vessel-wall shear stress

Atherosclerotic lesions in the carotid artery bifurcation (correct)

Increased blood pressure

Which patient demographic is most likely to benefit from carotid endarterectomy (CEA) according to research?

Patients with less than 50% stenosis

Patients with symptomatic stenosis of 50%-99% (correct)

Patients with mild asymptomatic carotid stenosis

Patients under 50 years with symptomatic stenosis

What role does plaque structure play in carotid artery stenosis?

It may influence the risk of stroke. (correct)

It has no impact on stroke risk.

It is the sole determinant of ischemic events.

It is less important than the degree of stenosis.

What percentage of ischemic strokes are attributed to extra-cranial internal carotid artery stenosis?

5% Signup and view all the answers

In which anatomical area does carotid atherosclerosis most commonly develop?

Carotid bulb Signup and view all the answers

Which of the following interventions is most critical in preventing aspiration in stroke patients?

Positioning the head of bed at least 30 degrees Signup and view all the answers

What is indicated for patients with evidence of oropharyngeal dysfunction?

Nothing by mouth until evaluated by a speech pathologist Signup and view all the answers

What is the recommended monitoring duration for cardiac function after a stroke?

48 hours Signup and view all the answers

What is the optimal range for arterial blood pressure in patients post-stroke?

160-200 mm Hg systolic Signup and view all the answers

What percentage range depicts the chance of concomitant cerebral and myocardial ischemia occurring together?

3%-20% Signup and view all the answers

In managing stroke patients, what condition should be initially avoided to prevent further complications?

Hypotension Signup and view all the answers

What should be done if ischemic ECG changes or abnormal cardiac troponin levels are observed?

Serial ECG and cardiac troponin monitoring Signup and view all the answers

What is often a critical step in the emergency care of a stroke patient?

Maintain an open airway Signup and view all the answers

Which complication has a mortality rate as high as 15%-25% in stroke patients?

Pneumonia Signup and view all the answers

What should be prioritized during the first 48-72 hours post-stroke?

Blood pressure monitoring Signup and view all the answers

Study Notes

Symptomatic Carotid Artery Stenosis

Atherosclerotic lesions at the carotid artery bifurcation are a common cause of stroke.
Approximately 5% of ischemic strokes are attributed to extra-cranial internal carotid artery stenosis.
Carotid atherosclerosis typically forms in regions with low vessel-wall shear stress, particularly at the carotid bulb.
The severity of carotid artery stenosis is important, but the structure of the plaque may also significantly influence stroke risk.

Stroke Overview

A 56-year-old man experienced a transient ischemic attack and two ischemic strokes in the right middle cerebral artery (MCA) distribution.
Due to recurrent strokes with 65%-70% focal stenosis of the M1 segment of the right MCA, a Wingspan intracranial stent was placed.

Stroke Treatment Protocols

Stroke patients require treatment in specialized stroke units or intensive care units.
Specialized stroke care correlates with lower mortality rates, shorter hospital stays, fewer discharges to nursing homes, and reduced costs.
Formation of a stroke team can expedite emergency response and care quality.
Emergency care must prioritize airway protection to prevent airway obstruction, hypoventilation, and aspiration.

Emergency Care Interventions

Monitoring with pulse oximetry or arterial blood gases is recommended.
Supplemental oxygen and ventilatory support should be provided if required.
Mild hypothermia can protect the brain from ischemic damage, while hyperthermia can worsen outcomes.
Bedridden patients or those with oropharyngeal impairments need measures to prevent pulmonary complications, as pneumonia mortality rates can reach 15%-25% in stroke patients.

Aspiration Risks and Management

Aspiration is common in stroke patients: over a third in brainstem strokes, one-fourth in bilateral hemispheric strokes, and one-tenth in unilateral hemispheric strokes.
For patients with oropharyngeal dysfunction, temporary enteral feeding tubes may be necessary for nutrition and medication administration.
Patients showing mild oropharyngeal dysfunction should not receive oral intake until assessed by a speech pathologist.

Cardiac Function Assessment

Following stroke, assessment of cardiac function and blood pressure is crucial.
Continuous cardiac monitoring for 48 hours is recommended due to high rates of cardiac dysfunction post-stroke.
A 12-lead ECG and troponin level tests should be conducted immediately upon admission.
Concomitant cerebral and myocardial ischemia can occur in 3%-20% of stroke cases.

Blood Pressure Management

Ischemic strokes may complicate with various cardiac arrhythmias; abnormal ECG or troponin levels necessitate serial monitoring.
Blood pressure should be closely monitored for 48-72 hours due to transient elevations post-stroke.
Optimal post-stroke blood pressure targets are 160-200 mm Hg for systolic and 70-110 mm Hg for diastolic pressures.
Both lower and higher blood pressure ranges can correlate with increased stroke volumes on CT scans within 4-7 days post-event.
Management of transient blood pressure elevations remains controversial, with the need to avoid overtreatment that could lead to hypotension.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz focuses on the surgical therapy for symptomatic carotid artery stenosis, a significant contributor to ischemic strokes. It covers the development of atherosclerosis in the carotid artery and the implications of plaque structure and stenosis degree in stroke risk.