Thrombotic
C. p.g 1459
Brain attack. P.g 1459
D. P.g 1463
Thrombotic, Emboli, Intracerebral , Subarachnoid. P.g 1462, table 58-1
Thrombotic: Cause by injury to a blood vessel wall and formation of a blood clot. Associated preexisting patho.: the lumen of the blood vessel becomes narrowed and if it becomes occluded, infarction occurs. This is the main difference between TIA and stroke, for in a TIA, ischemia occurs without infarction, unlike in a stroke where infarction and cell death occurs. 2/3 of thrombotic strokes are associated with HTN and DM, both of which accelerates atherosclerosis. S/S develop slowly. Neurological deficits: HA, Nausea, because in 30-50% of patients, thrombotic strokes are preceded by a TIA. LOC: No, unless it is due to a brainstem stroke, seizures, increased ICP, hemorrhage. Seizure Activity: Yes , when the patient has a seizure condition. Tx : Use of warfarin like Coumadin and ( tPA )IV.
Emboli : Cause by an embolus lodging in and occluding a cerebral artery resulting in infarction and edema of the area supplied by the involved vessel. Asso. Preexisting Patho. : An embolus is a blood clot or other debris circulating in the blood, when it reaches an artery in the brain that is too narrow to pass through, it lodges there and blocks the blood flow. Onset is usually sudden and may or may not be related to activity. Neurological deficits: They are initially severe like HA, blurred vision, but can be temporary if the clot breaks up and allows blood flow. LOC : Usually conscious, but may have a HA. Seizure Activity: No. Tx : Use of Antiplatelet agents like ASA, Plavix, and ( tPA) IV.
TIA : Cause by neurologic dysfunction of the focal brain, spinal cord, or retinal ischemia, but without acute infarction of the brain. Asso. Preexisting Patho.: There is a warning of brief interruption of blood to the brain which could last a few minutes to 24 hrs. These are warning signs of progressive CVA. S/S depend on the blood vessel that is involved and the area of the brain that is ischemic. Neurological deficits : Ataxia, tinnitus, vertigo, ptosis, blurred vision. LOC : No. Seizure Activity: No. Tx: Main goal is prevention of stroke by treating the risk factors like increased HTN, DM, Heart diseases.
Hemorrhage: Cause by rupture of a vessel leading to bleeding within the brain and rupture of a cerebral aneurysm. Asso. Preexisting Patho.: Intracerebral type of hemorrhage accounts for 10% of all strokes and HTN is the most important cause. Extent of S/S varies depending on the amount and duration of the bleeding. Hemorrhage in the pons is the most serious as respiration is rapidly affected leading to fixed pupil, coma or death. The Subarachnoid is caused by rupture of a cerebral aneurysm and are located in the Circle of Willis. This is a silent killer as pt. do not have a warning