(Answered)
Define CVA
Sudden onset of neurologic signs and symptoms resulting from disturbance of blood
supply to brain
Transient ischemic attack (TIA)
Temporary interruption in blood supply to brain; symptoms resolve in
24 hours
State the etiology of a CVA
1. Ischemia (87%)
a. Thrombosis
- Formation of blood clot within cerebral, carotid, or vertebral arteries
- Most often caused by atherosclerosis
b. Embolism
- Blood clot forms elsewhere and travels to cerebral, carotid or vertebra arteries
- Most often caused by atrial fibrillation, myocardial infarction, or cardiac valve disease
c. Low system perfusion
- Heart failure
- Significant blood loss
2. Cerebral hemorrhage
- Bleeding into brain
- Wall of vessel weakened by aneurysm
- Progressive dilation and eventual burst of arteriovenous malformation (AVM)
- Most often caused by hypertension, aging, trauma
List the risk factors of CVA
1. Hypertension
2. Diabetes mellitus
3. Hyperlipidemia
4. Heart arrhythmias
5. Smoking/tobacco use
6. Heavy alcohol use
7. Cocaine/amphetamine use
8. Coronary artery disease
9. Chronic heart failure (CHF)
10. Peripheral arterial disease
11. Chronic kidney disease
12. Sleep apnea
, 13. Early menopause
14. Use of estrogen
15. Obesity
16. Diminished physical activity
Explain the pathophysiology of CVA
1. Cerebral edema
a. Most frequent cause of death from infarction
b. Causes
- Tissue necrosis
- Rupture of cell membranes
- Movement of fluid from blood vessels to interstitial spaces
c. Results in increased intracranial pressure
2. Chemical irritation from hemorrhagic stroke causes vasospasm
3. Ischemic cascade: series of events that damage neurons
- Inability of brain cells to produce energy
- Formation of free radicals
- Release of nitric oxide and cytokine-increased inflammation
Frontal lobe
1. Primary motor cortex
2. Cognitive function
3. Motor function of speech (Broca's area)
Parietal lobe
1. Primary somatosensory cortex
2. Perception (attach meaning to sensory information)
Temporal lobe
1. Auditory cortex
2. Meaning of speech sounds (Wernicke's are)
3. Memory
Occipital lobe
1. Primary visual cortex