Transcript stroke
CVD: STROKE Septemius A. Pansacola RN,MD ANATOMY OF THE BRAIN ANATOMIC DIVISION Two cerebral hemispheres Brain stem • Midbrain • Pons • Medulla cerebellum Lobes of the cerebral hemisphere Frontal lobe • • • • Planning and sequencing of movement Voluntary eye movement Emotional affect Broca’s area Parietal lobe • Subserve motor control and cortical sensation • Dominant: governs motor program • Nondominant: governs spatial orientation Lobes of the cerebral hemisphere Temporal lobe • Subserve olfaction • Memory • Certain components of auditory and visual perception • Wernicke’s area Occipital lobe • Visual perception and involuntary eye movement Vessels supplying blood to the brain Anterior Circulation • Anterior Cerebral Artery • Middle Cerebral Artery Posterior Circulation • Posterior Cerebral Artery Anterior Circulation anterior cerebral artery • extends upward and forward from the internal carotid artery • supplies the frontal lobes, the parts of the brain that control logical thought, personality, and voluntary movement, • Stroke in the anterior cerebral artery results in opposite leg weakness. Anterior Circulation Middle Cerebral Artery largest branch of the internal carotid. supplies a portion: • frontal lobe • lateral surface of the temporal and parietal lobes • includes the primary motor and sensory areas of the face, throat, hand and arm and in the dominant hemisphere, the areas for speech. artery most often occluded in stroke lenticulostriate arteries Small, deep penetrating arteries which branch from the middle cerebral artery lacunar strokes Posterior Circulation Posterior cerebral artery Originates in the • basilar artery • ipsilateral internal carotid artery supply the temporal and occipital lobes Infarction: • usually secondary to embolism • vertebral basilar system or heart. The most common finding is occipital lobe infarction leading to an opposite visual field defect Circle of Willis Arterial anastomosis of vessels that enables the entire brain to reliably vascularized World Health Organization neurological deficit of cerebrovascular cause that persists beyond 24 hours or is interrupted by death within 24 hours' stroke blood supply to a part of your brain is interrupted or severely reduced: • oxygen and nutrients. caused by • thrombosis, embolism, or hemorrhage Stroke is a medical emergency. • Early treatment can also minimize damage to your brain and potential disability. epidemiology It is the third leading cause of death and the leading cause of adult disability in the United States and industrialized European nations. Risk factors advanced age Hypertension previous stroke or TIA (transient ischaemic attack) diabetes mellitus high cholesterol cigarette smoking atrial fibrillation Migraine with aura thrombophilia Stroke Warning Signs Sudden weakness, paralysis, or numbness of the face, arm and the leg on one or both sides of the body Loss of speech, or difficulty speaking or understanding speech Dimness or loss of vision, particularly in only one eye Unexplained dizziness (especially when associated with other neurologic symptoms), unsteadiness, or sudden falls Sudden severe headache and/or loss of consciousness Types of Stroke Strokes may be classified into two general types: • ischemic • hemorrhagic Types of Stroke Ischemic Stroke 80% of strokes are ischemic • 50%: cerebral thrombosis 30% of strokes: Large-vessel thrombosis • (e.g., carotid, middle cerebral, or basilar arteries) 20% involve small, deeply penetrating arteries • (e.g., lenticulostriate, basilar penetrating, medullary): lacunar stroke. • 30%: cerebral embolism most frequently: heart or from the cervical portion of the carotid artery more common in younger patients develop rapidly maximum deficit usually present within seconds to minutes. Hemorrhagic stroke 20% of all strokes • intracerebral hemorrhage also called a parenchymal hemorrhage The major risk factor: hypertension • Minute dilations at small artery bifurcation Occurs: basal ganglia and thalamus Most signs and symptoms • compression of brain structures and blood Berry Aneurysm • subarachnoid hemorrhage usually follows the rupture of an aneurysm or an arteriovenous malformation Systemic hypoperfusion reduction of blood flow to all parts of the body. • all parts of the brain may be affected most commonly due • cardiac pump failure/ low cardiac output Cardiac arrest Arrhythmias pulmonary embolism pericardial effusion or bleeding Signs and symptoms brainstem: 12 cranial nerves • altered smell, taste, hearing, or vision (total or partial) • drooping of eyelid (ptosis) and weakness of ocular muscles • decreased reflexes: gag, swallow, pupil reactivity to light • decreased sensation and muscle weakness of the face • balance problems and nystagmus • altered breathing and heart rate • weakness in sternocleidomastoid muscle (SCM) with inability to turn head to one side • weakness in tongue (inability to protrude and/or move from side to side) Signs and symptoms cerebral cortex • aphasia • • • • • Brocas area Wernicke's area apraxia (altered voluntary movements) visual field defect memory deficits Hemineglect disorganized thinking, confusion, hypersexual gestures cerebellum • trouble walking • altered movement coordination • vertigo and or disequilibrium Diagnosis neurological examination blood tests CT scans MRI scans Doppler ultrasound arteriography CT vs. MRI For diagnosing ischemic stroke in the emergency setting CT scans (without contrast enhancements) • sensitivity= 16% • specificity= 96% MRI scan • sensitivity= 83% • specificity= 98% For diagnosing hemorrhagic stroke in the emergency setting CT scans (without contrast enhancements) • sensitivity= 89% • specificity= 100% MRI scan • sensitivity= 81% • specificity= 100% Doppler ultrasound Internal Carotid stenosis Carotid endarterectomy Angiography Treatment Ischemic Stroke • antiplatelet medication aspirin Clopidogrel Dipyridamole anticoagulant medication warfarin • Thrombolysis Tissue plasminogen activator first 3 hours • Mechanical Thrombectomy • Hemorrhagic stroke must be ruled out with medical imaging Mechanical Thrombectomy Treatment Hemorrhagic stroke • Neurosurgical evaluation detect and treat the cause of the bleeding. • Patients are monitored and their blood pressure, blood sugar, and oxygenation are kept at optimum levels. Care and rehabilitation help the survivor: • adapt to difficulties • prevent secondary complications • educate family members to play a supporting role. rehabilitation team • nursing staff, physiotherapy, occupational therapy, speech and language therapy, and usually a physician trained in rehabilitation medicine