Thank you to the following 2013 Year Two students who devoted their time and effort to developing the following seminar topic: Eve Skogstad Laura Cumberlege Cameron Urgert Some content may differ from that originally created by these students
Overview Type of strokes - Ischemic (emboli, thrombosis, atherosclerosis and TIA) - Haemorrhage (sub-arachnoid, intracerebral) Signs and symptoms Effects
A stroke is the rapid loss of brain function due to disturbance in the blood supply to the brain This can be due to: ◦ Blockage (thrombosis, embolism) ◦ Haemorrhage ◦ Resulting in Ischemia (lack of blood flow which causes cell death to the area affected)
Blood flow is impaired because of a blockage to one or more of the arteries supplying blood to the brain caused by either: Thrombosis: Blood changes from a liquid to a solid state and produces a blood clot (thrombus). It obstructs the blood flow at the site of the blood clot formation. Emboli: foreign body is carried by the blood from one point in the circulation to lodge at another point. Atherosclerosis: Unhealthy blood vessels are clogged with a build-up of fatty deposits and cholesterol. Your body regards these build ups as multiple, tiny and repeated injuries to the blood vessel wall and responds by forming clots.
Caused by a break in the wall of a blood vessel in the brain. This causes blood to leak into the brain, again stopping the delivery of oxygen, glucose and nutrients. Haemorrhagic stroke can be caused by a number of disorders which affect the blood vessels, including long- standing high blood pressure and cerebral aneurysms. The two types of haemorrhagic strokes are: Sub Arachnoid - Bleeding into the subarachnoid space. occur spontaneously, usually from a ruptured cerebral aneurysm of one of the arteries and their branches of the circle of Willis, or may result from a head injury. Intracerebral - Bleeding occurs within the brain tissue itself
A Transient Ischemic Attack (TIA) is often labeled as a “mini-stroke” or “warning stroke”. TIA is caused by a clot; the only difference between a stroke and TIA is that with TIA the blockage is transient (temporary). TIA symptoms occur rapidly and last a relatively short time. Most TIAs last less than five minutes; the average is about a minute. Unlike a stroke, when a TIA is over, usually causes no permanent injury to the brain.
http://www.youtube.com/watch?v=pcmrgwN CPwM&feature=endscreen&NR=1 http://www.youtube.com/watch?v=pcmrgwN CPwM&feature=endscreen&NR=1 Until 3.06 (Treatment)
Proposed systems include F.A.S.T (Face, Arm, Speech, and Time) Face drooping Arm weakness Speech difficulty Time, this represents the need to get to a hospital immediately
The effects of a stroke depend on several factors including: The location of the obstruction How much brain tissue is affected However, because one side of the brain controls the opposite side of the body, a stroke affecting one side will result in neurological complications on the side of the body it affects
Right Brain If the stroke occurs in the brain's right side, the left side of the body (and the left side of the face) will be affected, which could produce any or all of the following: Paralysis on the left side of the body Vision problems Quick, inquisitive behavioral style Memory loss
Left Brain If the stroke occurs in the left side of the brain, the right side of the body will be affected, producing some or all of the following: Paralysis on the right side of the body Speech/language problems Slow, cautious behavioral style Memory loss
Brain Stem When stroke occurs in the brain stem, depending on the severity of the injury, it can affect both sides of the body and may leave someone in a ‘locked-in’ state. When a locked-in state occurs, the patient is generally unable to speak or achieve any movement below the neck.
Selected Stroke Syndromes Symptoms and SignsSyndrome Contralateral hemiparesis (maximal in the leg), urinary incontinence, apathy, confusion, poor judgment, mutism, grasp reflex, gait apraxia Anterior cerebral artery (uncommon) Contralateral hemiparesis (worse in the arm and face than in the leg), dysarthria, hemianesthesia, contralateral homonymous hemianopia, aphasia (if the dominant hemisphere is affected) or apraxia and sensory neglect (if the nondominant hemisphere is affected) Middle cerebral artery (common) Contralateral homonymous hemianopia, unilateral cortical blindness, memory loss, unilateral 3rd cranial nerve palsy, hemiballismus Posterior cerebral artery Monocular loss of vision (amaurosis)Ophthalmic artery (a branch of the middle cerebral artery) Unilateral or bilateral cranial nerve deficits (eg, nystagmus, vertigo, dysphagia, dysarthria, diplopia, blindness), truncal or limb ataxia, spastic paresis, crossed sensory and motor deficits*, impaired consciousness, coma, death (if basilar artery occlusion is complete), tachycardia, labile BP Vertebrobasilar system Absence of cortical deficits plus one of the following: Pure motor hemiparesis Pure sensory hemianesthesia Ataxic hemiparesis Dysarthria–clumsy hand syndrome Lacunar infarcts Reference: http://www.merckmanuals.com/professional/neurologic_disorders/stroke_cva/overview_of_stroke.html?qt=stroke&alt=sh http://www.merckmanuals.com/professional/neurologic_disorders/stroke_cva/overview_of_stroke.html?qt=stroke&alt=sh