Cerebrovascular Disease PDF

 Transient Ischemic Attack (TIA) o Angina of the brain o Transient = temporary; often lasting less than 1 hour o Temporary and reversible reduced blood flow and oxygen to the brain o Ischemia: a localized area of reduced arterial blood and oxygen flow  S/S depend on the cells and tissues deprived...

 Transient Ischemic Attack (TIA) o Angina of the brain o Transient = temporary; often lasting less than 1 hour o Temporary and reversible reduced blood flow and oxygen to the brain o Ischemia: a localized area of reduced arterial blood and oxygen flow  S/S depend on the cells and tissues deprived of blood and oxygen  S/S of altered perfusion are dependent on the tissue that is ischemic  eFAST o e = eyes. Deviation of the eyes or sudden or temporary loss of all or part of your vision o F = face. Sudden facial numbness or weakness especially on one side of the body o A = arm. Sudden arm and/or leg numbness or weakness especially on one side of the body. o S = speech. Slurred speech and difficulty speaking or understanding what is being said o T = time. Time to call 911 o Reason for short term symptoms in persons with TIA  Clots are quickly lysed  Body releases plasminogen activator (tPA) o tPA  plasminogen to plasmin  fibrinolysis  blood vessels in the area dilate to allow blood to perfuse tissue  or blood is rerouted around the obstruction  vessel occlusion is incomplete o Why TIA is thought to be angina of the brain  There is temporary and reversible interruption in blood flow  There is a localized area of reduced blood and oxygen flow o Tissues are ischemic o Cellular changes are reversible  When cells become ischemic, they are more permeable to sodium.  Sodium moves into the cell and pulls water along with it  The cell swells o Warning that a major event could occur o Risk factors  Are those of atherosclerosis  Smoking  High LDL  Hypertension  High triglycerides  Obesity  Inactivity  T2DM o Hypercoagulation…a risk for TIA  Atherosclerosis results in slow moving arterial blood This study source was downloaded by 100000780651383 from CourseHero.com on 10-09-2023 15:30:14 GMT -05:00 https://www.coursehero.com/file/136603263/cerebrovacular-diseasedocx/ Blood the is not freely moving tends to clot  Static blood clots  Damaged endothelium attracts and activates platelets Etiologies  Atherosclerosis  Dysrhythmia  Emboli from the heart (a.fib) could result in TIA o Atria quiver, don’t contract  blood is static in atria  static blood clots (thrombus forms in atria)  embolus breaks away from thrombus in left atrium  falls into left ventricle  pumped out through aortic valve  up to aortic arch  carotid artery and on into the brain  Hypotension  Orthostatic hypotension: drop in BP when person sits or stands  Episode of hypotension  decrease perfusion through narrowed blood vessels  risk for ischemia, thrombus formation  TIA  Orthostatic Hypotension and TIA is of greatest concern in persons who already have: o Cerebrovascular disease o Or atherosclerosis  Bottomline  Related concern: altered perfusion o Reduced oxygen flow to part of the brain  Related to or caused by:  Narrow arterial lumen: atherosclerosis  Low orthostatic BP: in persons with history or TIA or cerebrovascular disease  Dysrhythmia: can lower the CO and BP; a.fib  Short term symptoms often last less than 1 hour o Symptoms resolve because  Body produces tPA that lysis the clot  Occlusion was incomplete  Arterial blood is rerouted around the obstruction  Workup for TIA o Presenting S/S related to altered perfusion  Dizzy  Numbness in face and arm o History  Identify risk factors for TIA o Physical  Suggestive findings  Could be normal  Carotid bruit  o This study source was downloaded by 100000780651383 from CourseHero.com on 10-09-2023 15:30:14 GMT -05:00 https://www.coursehero.com/file/136603263/cerebrovacular-diseasedocx/ o  It’s the sound blood makes when it passes through a narrow opening. A bruit is to an artery what a murmur is to the cardiac valve disease. A bruit and a murmur are both caused by abnormal blood flow o use of ultrasound to confirm a bruit and determine severity of vessel narrowing o Ultrasound Followed Up with CT Angiography o Treatment  Treatments to help perfusion  tPA  Anticoagulants o Antiplatelets  Angioplasty and stenting o purpose of placing a CAROTID ARTERY STENT  pushes back the plaque against the wall of the artery  Endarterectomy o Physical removal of plaque from the carotid artery  MERCI procedure o Mechanical Embolus Removal in Cerebral Ischemia o Clot hooked onto catheter and manually pulled from the artery Brain attack aka Stroke o Cells in the brain have died/necrosis o A leading cause mortality and morbidity o Incidence  Increase with age  Men affected more than women o Atherosclerosis is major risk factor o May present the same as someone with TIA (eFAST) o signs and symptoms suggestive for brain attack [stroke] depend on the tissues affected. o Named by the area of the brain that is affected  Right sided hemispheric brain attack results in left side paresis (partial paralysis) or full paralysis  Contralateral  opposite side o Slurred speech o Facial droop o Ataxia  loss of balance o Wernike’s aphasia: clear speech, but impaired meaning and poor understanding o Broca’s aphasia: affects speaking and writing; can comprehend language o Visual field changes  Hemianopia: loss of half your visual field in both eyes  Occurs when brain attack happens at an optic tract o etiology of dysphagia  difficulty swallowing This study source was downloaded by 100000780651383 from CourseHero.com on 10-09-2023 15:30:14 GMT -05:00 https://www.coursehero.com/file/136603263/cerebrovacular-diseasedocx/ result of brainstem stroke, cranial cell body damage, impaired nerve transmission  Up to 30 – 50% of persons with hemispheric stroke  Most resolve in a week Left Hemispheric [Dominant] Brain Attack  Movement: right hemiparesis  Aphasia: Speaking: Broca’s Expressive; Understanding: Wernike’s Receptive  Dysphagia Right Hemispheric Brain Attack  Left Hemiparesis  Left visual field deficit  Dysphagia Level of consciousness issues  Ischemia and necrosis  inflammation  swelling  increased intracranial pressure is possible  decrease blood supply and further reduce blood and oxygen to brain  deteriorating LOC Brain attack can be either ischemic or hemorrhagic  80% related to ischemia, which most of those are from atherosclerosis Diagnosing brain attack  Ischemic brain attack = artery blockage  MRI  Penumbra = ischemic tissue around the necrosis; cells at risk but potentially salvageable with reperfusion  Goal = re-perfuse and save the tissue  Hemorrhagic brain attack = bleeding into the brain tissue Treatment  tPA within 3 hours of the onset of symptoms  door-to-needle  goal: re-perfuse in 60 minutes or less  angioplasty  stenting  endarterectomy – save some of the tissue Reduce risk of ischemic brain attack recurring  Anticoagulant therapy  Antiplatelet  Other  Treat other conditions such as atrial fib  Thrombus form in the atria, if piece were to break off and fall into left ventricle it’ll be pumped to the brain and could result in an ischemic brain attack  Slow down the progress of atherosclerosis – a chronic, often progressive condition  Life style modification o Stop smoking  o o o o o o o This study source was downloaded by 100000780651383 from CourseHero.com on 10-09-2023 15:30:14 GMT -05:00 https://www.coursehero.com/file/136603263/cerebrovacular-diseasedocx/ o o Control BP o Achieve/maintain more reasonable weight o Control of blood sugar Hemorrhagic brain attack  Excessive flow of blood occurring in the tissues of the brain  Blood vessel has burst  Can occur due to increased BP  rigid vascular container cannot “give”… increased pressure in blood vessels with limited “give  results in container bursting  Symptoms may evolve over time  Related to blood outside the vessels o Blood = volume…increased volume in cranial cavity  increased pressure  compress blood vessels  ischemia  Protein creates a “pull”  more plasma leaves blood vessels and enters tissue space  Increased volume  increased pressure  compression of blood supply  more ischemic and worsening of S/S  Related to o Cells slowly dying o Cell death  inflammation  Inflammation  fluid shifts from inside the arteries  to outside the arteries  increases “size” of brain… increases volume in cranial cavity  compression of additional blood vessels  more tissue ischemia  Has a high mortality rate  Related to o Impaired perfusion  increased amount of tissue lost o Increased intracranial pressure  Blood in cranial cavity  increases pressure  Ischemia  inflammation  more increase in pressure  More tissue lost  Hypertension and advancing age are common risk factors  CT scan or MRI for diagnosis  Treatment  Don’t give anticoagulants  Supportive  airway, breathing and circulation  Anticonvulsants  for seizures  Antihypertensive agent  if BP is too high  Osmotic diuretics  to pull fluid from the brain in attempt to decrease volume and decrease pressure  Stop source of bleeding if you can This study source was downloaded by 100000780651383 from CourseHero.com on 10-09-2023 15:30:14 GMT -05:00 https://www.coursehero.com/file/136603263/cerebrovacular-diseasedocx/ Powered by TCPDF (www.tcpdf.org)