CVA Ischemic and Hemorrhagic

Pathophysiology Stroke is a rapid development of focal neurologic deficit caused by a disruption of blood supply to the corresponding area of the brain. To be classified as a stroke the neurological deficits need to persist for at least 24 hours A stroke is termed a transient ischemic attack (TIA) if less than 24 hours TIA risk factor A variety of focal deficits are possible changes in consciousness sensory, motor, language, cognitive, and perceptual impairments motor deficits are characterized by paralysis (hemiplegia) or weakness (hemiparesis) typically on the side opposite of the lesion

Pathophysiology Hemorrhagic Rupture of a blood vessel with abnormal bleeding into extravascular area of brain usually the result of rupture of cerebral vessel or trauma Primary cerebral hemorrhage (non-traumatic spontaneous hemorrhage) usually occur in small blood vessels weakened by atherosclerosis which produces an aneurysm Subarachnoid hemorrhage occurring from bleeding into the subarachnoid space typically from a saccular or berry aneurysm affecting large blood vessels. Can be intracerebral which is bleeding within the brain or subarachnoid

Pathophysiology Ischemic Occlusion of a blood vessel from thrombus, embolism, or conditions that produce low systemic perfusion pressure Cerebral thrombosis is a formation or developing clot within the cerebral arteries or their branches. Thrombi can lead to ischemia or occlusion of an artery which could result in a cerebral infarctions or tissue death (atherothrombotic brain infarction [ABI]) subtypes include large artery, atherosclerosis, cardiogenic embolism, small vessel occlusive disease

Risk Factors Major risk factors heart disease hypertension diabetes Risk factors such as diabetes mellitus, hyperlipidemia, cigarette smoking, and hypertension fail to distinguish between ischemic and hemorrhagic types of stroke. Having a TIA is a risk factor for stroke with about 10% of people having a major stroke within 90 days

Specific Risk Factors Ischemic stroke Age: elderly over 80 Race: from greatest to least risk black > hispanic > white Sex: More men than women except in the age range Family History: monozygotic twins Hemorrhagic stroke Age: elderly Sex: no significant difference between men and women except during pregnancy and postpartum Race/Ethnicity: Asians > African Americans > Hispanics/Native Americans > Whites Genetics: Icelandic CAA and Dutch CCA

Early Warning Signs of Stroke Sudden numbness or weakness of the face, arm, or leg especially on one side of the body Sudden confusion, trouble speaking or understanding Sudden trouble seeing in one or both eyes Sudden trouble walking, dizziness, loss or balance or coordination Sudden severe headaches with no know cause Sudden nausea, fever or vomiting distinguished from a viral by the speed of onset (minutes or hours vs several days) Brief loss of consciousness or a period of decreased consciousness (fainting, confusion, convulsions, or coma)

Signs and Symptoms Clinical features of a hemorrhagic stroke include: severe headache from increased intracranial pressure progressive deterioration from continued bleeding vomiting from increased intracranial pressure neck stiffness from meningeal irritation bilateral babinski signs from enlargement of hemorrhage beyond the blood vessel involved coma from bilateral cerebral dysfunction or uncal herniation greater arm and leg hemiparesis

Signs and Symptoms Common presentation of a patient with ischemic type of stroke: previous TIA numbness and uncoordinated extremity movements alert mental status but may struggle with generating words mild hemiparesis facial paralysis mild headache absence of severe hypertension absence of Babinski sign Positive for dorsiflexion of the great toe with fanning of the other toes on stimulation of the lateral plantar surface of the foot

How is the Patient Affected? BOTH ischemic and hemorrhagic types of stroke may cause neurological deficits such as hemiparesis, hemisensory loss, aphasia, opthalmoplegia and visual field cuts Hemorrhagic stroke may cause additional symptoms due to leakage of blood that displaces and compressing surrounding brain tissues

Special Tests A TIA is a predictor of ischemic type stroke The greatest risk of stroke is within 90 days after the TIA with half occurring within first 7 days. All patients with a new stroke need to undergo a CT to distinguish between hemorrhagic and ischemic stroke Babinki Test for ischemic or hemorrhagic No findings or combination of findings suggest are definitive of either type of stroke To rule in/out either type of stroke requires neuroimaging to be absolutely certain

References Grysiewicz, Rebbeca A. et al. Epidemiology of Ischemic and Hemorrhagic Stroke: Incidence, Prevalence, Mortality, and Risk Factors. Neuro Clin (2008); 26: Khaw, Kay-Tee. Epidemiology of Stroke. Journal of Neurology, Neurosurgery and Psychiatry (1996); 61: Runchey, Shauna and McGee, Steven. Does This Patient Have Hemorrhagic Stroke? Clinical Findings Distinguishing Hemorrhagic Stroke from Ischemic Stroke. JAMA (2010); 303;