NURS 305-Week Nine Textbook Reading Notes Questions

what is a stroke? occurs when there is ischemia to a part of the brain or hemorrhage into the brain cerebral arteries carry blood to the brain and the brain needs a constant flow of oxygen to survive which arteries supply anterioir circulation? internal carotid arteries which arteries supply posterior circulation? vertebral arteries Which parts of the brain are supplied by the internal carotid arteries? frontal lobe parietal lobe temporal lobes basal ganglia part of the diencephalon (thalamus and hypothalamus) what are the major branches of the carotid arteries? middle cerebral arteries anterioir cerebral arteries the vertebral arteries join to form the basilar artery which branches to supply which part of the brain? middle and lower parts of temporal lobe occipital lobes cerebellum brainstem part of the diencephalon What is the main branch of the basilar artery? posterior cerebral artery image to help learn (WARNING THIS IMAGE MAKES ME SO NAUSEOUS) Where is anterioir and posterioir circulation connected? at the circle of willis by the anterior and posterioir communicating arteries What is cerebral autoregulation? The mechanism by which the brain protects itself from changes in MAP by vasodilation and constriction. what are some factors that affect blood flow to the brain? systemic BP cardiac output blood viscosity DID YOU KNOW THE CEREBRAL ARTERIES CAN ALSO GET ATHEROSCLEROSIS? ITS THE EXACT SAME AS ATHEROSCLEROSIS IN THE HEART SO JUST MAKE SURE U KNOW IT FROM THAT AND YOU CAN TRANSFER THAT THINKING What is the ischemic cascade? Ishcemia--> Metabolic changes--> Diastolic dysfucntion-->Systolic dysfunction-- >Ekg changes-->chest pain what is penumbra? around the core area of ischemia and is a border zone where ischemia can potentially be reversed If adequate blood flow can be resored in _____ hours and the ischemic cascade can be interrupted, brain damage may be minimized and less neurological function may be lost. 3 hours What are some Nonmodifiable risk factors of stroke? age sex indigenous, african, south asian heritage family and medical history personal circumstances (access to safe drinking water) What is an arteriovenous malformation? an abnormal group of tangled arteries and veins AVMs can occur anywhere in the body but pose the greatest risk in the brain What are some modifiable risk factors of stroke? hypertension heart disease (Afib, MI, cardiomypathy, cardiac valve abnormalities) diabetes mellitus increased serum cholesterol levels and carotid stenosis birth control pills (progestin and estrogen) use of illicit drugs obesity What is an ischemic stroke? result from inadequate blood flow to the brain from partial or complete occlusion of an artery and account for the majority of strokes What are the two types of ischemic strokes? thrombotic embolic What is a transient ischemic attack? a temporary episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia but without acute infarction of the brain What are some causes of TIAs? microemboli or plaque that temporariy block blood flow TIAs are a warning sign of cerebrovascular disease what does dysarthia mean? disturbance in the muscular control of spech What is a thrombotic stroke? occurs when a blood clot forms in a diseased and narrowed blood vessel in the brain if the narrowed part of the lumen becomes occluded infarction occurs thrombosis often occurs in areas of narrowed blood vessels What is a lacunar stroke? a stroke from occlusion of a small penetrating artery that supplies blood to tissue deep within the brain (typically occurs in basal gangllia, thalamus) What is an embolic stroke? occurs when an embolus lodges in and occludes a cerebral artery resulting in infarction and edema of the area supplied by the involved vessel What are some of the clinical symptoms someone experiencing an embolic stroke might have? they will have a raoud occurence of severe clinical symptoms the patient usually remains conscious may or may not experience a headache