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Stroke Stroke is acute, focal brain dysfunction due to vascular disease , is the third most common cause of death in high-income countries after cancers and ischaemic heart disease, and the most common cause of severe physical disability. Stroke accounts for 11% of deaths in England and Wales; About 750 000 new strokes occur and about 150 000 people die from stroke in the United States each year.Around half of all stroke survivors are left dependent on others for everyday activities: if a patient can return home, the burden on carers is significant.One-quarter of all strokes occur in people below the age of 65 years.. The underlying pathology responsible for the persistent symptoms of stroke is either infarction or haemorrhage. Haemorrhage is subdivided according to location into intracranial haemorrhage and subarachnoid haemorrhage,while infarction is caused by either embolic (Sudden) or thrombotic (gradual) The main arterial supply of the brain comes from the internal carotid arteries, which supply the anterior brain, and the vertebral and basilar arteries (vertebrobasilar system), which provide the posterior circulation. The anterior and middle cerebral arteries supply the frontal and parietal lobes, while the posterior cerebral artery supplies the occipital lobe. The vertebral and basilar arteries perfuse the brain stem and cerebellum; Communicating arteries provide connections between the anterior and posterior circulations and between left and right hemispheres, creating protective anastomotic connections that form the circle of Willis. Three Stroke Types Ischemic Stroke Intracerebral Hemorrhage Subarachnoid Hemorrhage Clot occluding artery 85% Bleeding into brain 10% Bleeding around brain 5% When infarction involves only a small volume of the tissue (<1.5 cm in diameter on computerized tomography [CT]) secondary to occlusion of a penetrating artery, the resulting death of tissue is known as a lacune or a lacunar infarct. The underlying pathology responsible for lacunar infarction is often referred to as small vessel disease. Lacunes are generally found in subcortical white matter or the basal ganglia. Larger infarcts usually involve a wedge of both cortical and subcortical white matter and result from occlusion of the trunk or branches of the major cerebral arteries. Vessel Stroke Syndromes o Middle cerebral artery (MCA): –Arm>leg weakness –Left (MCA) : Aphasia –Right (MCA ) : Neglect o Anterior cerebral artery (ACA): –Leg>arm weakness, Voluntary control of micturition may be impaired o Posterior cerebral artery (PCA): –Hemianopia o Cerebellar arteries --ipsilateral ataxia o Brain stem vessels Cross signs (ipsilateral cranial nerve plus contralateral weakness or sensory loss) eg: Posterior inferior cerebellar artery occlusion(PICA): results in the lateral medullary (Wallenberg) syndrome . This syndrome varies in its presentation with the extent of infarction, but it can include ipsilateral cerebellar ataxia, Horner syndrome, facial sensory deficit and dysphagia ; contralateral impaired pain and tempreture.The motor system is characteristically spared because of its ventral location in the brainstem. Risk factors for stroke Non modifiable risk factors • Age • Gender (male > female except at extremes of age) • Race (Afro-Caribbean > Asian > European) • Previous vascular event Myocardial infarction Stroke Peripheral vascular disease • Heredity Modifiable risk factors • hypertension • smoking • Hyperlipidaemia • Diabetes mellitus • Excessive alcohol intake •Oral contraceptive pill • Polycythaemia • Heart disease Atrial fibrillation Congestive cardiac failure •obesity Differential diagnosis of stroke and TIA • Brain tumours •syncope •Hypoglycaemia • Migrainous aura • Focal seizures • Encephalitis •Demylination disease eg : multiple sclerosis • Conversion disorder Several terms have been used to classify strokes, often based on the duration and evolution of symptoms Transient ischaemic attack (TIA) describes a stroke in which symptoms resolve within 24 hours.. The term TIA also includes patients with amaurosis fugax, usually due to a vascular occlusion in the retina most likely due to caroted stenosis lead to transient foggy scene in one eye . Progressing stroke (or stroke in evolution) describes a stroke in which the focal neurological deficit worsens after the patient first presents. Such worsening may be due to increasing volume of infarction, haemorrhagic transformation or increasing cerebral oedema. Completed stroke describes a stroke in which the focal deficit persists and is not progressing Investigation of a patient with an acute stroke Is it a vascular lesion? …… CT/MRI Is there any cardiac source of embolism?..... (ECG) & Echocardiogram What is the underlying vascular disease?.... Duplex ultrasound of carotids What are the risk factors?..... Full blood count,lipid profile & blood glucose Management of acute stroke Airway :Perform bedside swallow screen and keep patient nil by mouth if swallowing unsafe or aspiration occurs. Breathing : Check respiratory rate and oxygen saturation and give oxygen if saturation < 95%. Circulation & BP: Unless there is heart or renal failure, evidence of hypertensive encephalopathy or aortic dissection, do not lower blood pressure in first week as it may reduce cerebral perfusion. Blood pressure after that should be controlled … Penumbra At the centre of an infarct the damage is most severe but at the periphery collateral flow may allow continued delivery of blood, although at a lower rate. This zone may become dysfunctional secondary to electrical failure although not dead and is referred to as the ischaemic penumbra, Once blood flow falls below the threshold for the maintenance of electrical activity, neurological deficit develops. At this level of blood flow the neurons are still viable; if the blood flow increases again, function returns; However, if the blood flow falls further, irreversible cell death occure. Consensus exists that medications should be withheld unless the systolic blood pressure is >220 mm Hg or the diastolic blood pressure is >120 mm Hg in early days unless there is contraindication to keep high BP or we decide to give thrombolytic drug. This high BP will help to reperfuse the penumbra and keep it viable.. Penumbra Core Clot in Artery Save the Penumbra Normal function 20 15 10 PENUMBRA 5 CORE 1 2 TIME (hours) Neuronal dysfunction CBF 8-18 Neuronal death CBF <8 3 CEREBRAL BLOOD FLOW (ml/100g/min) Nutrition & hydration : Assess nutritional status and provide nutritional supplements if necessary, If dysphagia persists for > 48 hrs, start feeding via a nasogastric tube.hydration by iv fluid may need use isotonic fluid eg:GS or NS avoid GW because it exacerbate brain odema . Blood glucose: Check blood glucose and treat when levels are ≥ 11.1 mmol/L (200 mg/dL) (by insulin infusion or glucose/potassium/insulin (GKI) ;Monitor closely to avoid hypoglycaemia Temperature: If pyrexic, investigate and treat underlying cause ,Control with antipyretics, as raised brain temperature may increase infarct volume. Incontinence : Check for urinary retention; treat Appropriately, Avoid urinary catheterisation unless patient is in acute urinary retention or incontinence is threatening. Immediate medication include: Thrombolysis Intravenous thrombolysis with recombinant tissue plasminogen activator (rt-PA, it should be given within 4.5 hours of symptom onset to carefully selected patients with inclusion and exclusion criteria. Aspirin In the absence of contraindications, aspirin (300 mg daily) should be started immediately after an ischaemic stroke unless rt-PA has been given, in which case it should be withheld for at least 24 hours. Aspirin reduces the risk of early recurrence and has a small but clinically worthwhile effect on long-term outcome. Strategies for secondary prevention Lifestyle modification Patients with the relevant risk factors should be strongly advised to stop smoking, eat healthily to reach and maintain a normal weight, to take regular exercise and reduce excessive alcohol consumption. Lowering blood pressure optimum targets: below 140/85 mmHg in general and below 140/80 mmHg for patients with diabetes ,started with thiazide diuretic and then add an ACE inhibitor, If further reduction in blood pressure is required, calcium antagonists can be added Antiplatelet drugs: Asprin 100 mg or clopidogril 75 mg or aspirin/dipyridamole Lipid lowering agent : Starting with a statin after ischaemic stroke dramatically reduces the risk of recurrent stroke and MI. Anticoagulation: Just in case of patients with cardio-embolic sources of thrombus such as AF (atrial fibrillation ) anticogulation will be indicated . Carotid endarterectomy: Ischaemic stroke or TIA with Recently symptomatic severe carotid stenosis Control of blood glucose: it is important to maintain HbAc1 levels at less than 7%. Complications of acute stroke Chest infection:Avoid aspiration (nil by mouth, nasogastric tube, possible gastrostomy) treatment by Antibiotics &Physiotherapy Epileptic seizures:Maintain cerebral oxygenation ,Avoid metabolic disturbance treatment by Anticonvulsants . Deep venous thrombosis/ pulmonary embolism : Maintain hydration ,Early mobilisation,Anti-embolism Stockings or Heparin. Painful shoulder:Avoid traction injury Shoulder/arm supports Physiotherapy, Local corticosteroid injections may needed . Pressure sores:Frequent turning, Monitor pressure areas Avoid urinary damage to skin, Nursing care And Pressure-relieving mattress. Urinary infection:Avoid catheterisation if possible Use penile sheath.. tratment by antibiotic. Depression and anxiety:Maintain positive Attitude, treatment by antidepressant. Constipation: Appropriate aperients and diet