Upload
amanda-sullivan
View
218
Download
3
Tags:
Embed Size (px)
Citation preview
Definition of a stroke
• Sudden onset
• Focal neurological disturbance e.g. speech problem, limb weakness
• Vascular in origin (i.e. blood clot or bleed)
• Symptoms last more than 24 hours
• Definition includes subarachnoid haemorrhage (bleeding which occurs from a small swelling in blood vessel in the brain) which presents with severe headache with or without focal neurology.
Definition of Transient Ischaemic Attack (TIA)
• Sudden onset • Focal neurological disturbance• Assumed to be vascular in origin• Lasts <24 hours
• Symptoms improve because blocked blood vessel spontaneously unblocks and blood supply returns
How common is a stroke?
• 3rd most common cause of death
• Commonest cause of disability; 50% survivors disabled at 6 months
• 120,000 strokes per year in UK
• 15,000 strokes per year in Scotland
• Approx. 700 hospital admissions per year in Edinburgh
• 2.3 million deaths due to stroke per year in U.S
Cortex
(movement, sensation, intellect, language etc)
Cerebellum
(balance and control of movement)
Brain stem
(controls breathing, blood pressure, sleep
etc)
Symptoms Depend on part of Brain Affected
Neurological effects of stroke (and TIA) • Weakness down one side of body (opposite side of brain)
• Poor balance
• Sensory symptoms (e.g. numbness)
• Speech problems: language (usually dominant i.e. left side of brain) (affects both production of language and understanding)
• Speech: articulation • Swallowing problems
• Visual problems (e.g. double vision, loss of visual field) • Dyspraxia (difficulty with complex tasks)
• Perceptual problems e.g. neglect• Memory and thinking
• Incontinence
Is it a Stroke or not? • Other medical conditions can ‘mimic’ a stroke (brain
tumour, seizure, migraine, low blood sugar, infection) • About a fifth of patients with suspected stroke turn
out not to have had a stroke
• Brain scans essential to exclude stroke ‘mimics’
• Two main types of brain scans: CT and MR
• CT is the most accessible type of imaging. MR less widely available
Two Main Types of Stroke
• Haemorrhage (due to bleeding into the brain): cause about 15% of strokes
• Ischaemic (due to a blocked blood vessel): cause about 80% of strokes
CT Scan of a Patient with a Haemorrhagic Stroke
Fresh blood shows up as a white ‘blob’
http://www.strokecenter.org/radiology/browser.aspx, case #14832
Oxfordshire Community Stroke Project Classification for: Haemorrhagic and Ischaemic Stroke
TACS • Visual field loss• Weakness arm or leg• Dysphasia or inattention
or dyspraxia
PACS • Only two of the three
symptoms of TACS
LACS • Weakness or sensory
loss• No other symptoms
POCS • (brain stem or cerebella
symptoms)
Total Anterior Circulation Syndrome (TACS)
• 60 year old lady• Found on floor by husband • Right sided weakness (no movement in arm, slight
movement leg)• Looking to left and ‘ignoring’ right side • Right facial droop • Right visual field loss • Drowsy• No speech and not following commands • Sounded ‘chesty’
Partial anterior circulation syndrome
(PACS)
• 80 year old man• Sudden onset right hand weakness whilst drinking a
cup of tea, spilt tea
• Difficulty finding the ‘right words’• Able to understand people• Vision fine, leg fine
• Symptoms improved over 48 hours, only mild right hand weakness remained
Typical stroke (Lacunar Syndrome)
• 58 year old lady
• Walking down the road
• Suddenly noted tingling in right arm and then some weakness in right arm and leg
• Speech was normal
• 5 years ago had had a similar episode on left side of body
Typical Stroke (Posterior Circulation Syndrome)
• 65 year old man• Sitting in a chair• Suddenly room starting spinning• Tried to get up, felt like he was ‘drunk’ and fell over• Double vision• Vomited
Referral for exercise:
Classification of Patients (data from STARTER)
0
5
10
15
20
25
30
35
TACS PACS LACS POCS
number
Possible descriptions of stroke when patients referred for exercise
Pathological subtype• Ischaemic, infarction
• Description of likely cause e.g. embolic
• Haemorrhagic, ‘intracerebral haemorrhage’, ‘ICH’, ‘PICH’
Classification• Oxfordshire Community
classification• Site of lesion on brain
scan– Middle cerebral
artery territory, posterior cerebral artery territory
Risk Factors for Ischaemic Stroke Common • Hypertension• Diabetes mellitus• Cigarette smoking• Atrial fibrillation• Carotid stenosis• Cardiac disease• Alcohol• High cholesterol• Obesity• Reduced physical activity• Diet
Rarer • Vasculitis• Polycythaemia• Leukaemia• Hyperviscosity• Thrombophilias• Anti-phospholipid
syndrome• Neurosyphilis• Endocarditis
Risk Factors and Causes of Haemorrhage
Primary Intracerebral Haemorrhage• Hypertension• Coagulation disorder• Aneurysm• Arterio-venous malformation (AVM)• Cigarette smoking• Amyloid angiopathy• Drug abuse
Causes of Ischaemic Stroke
• Blood clot forms in artery in brain e.g. middle cerebral, or small deep artery in brain
• Blood clot forms at another site and ‘travels’ to brain (embolism)– Aorta (main artery in chest)– Carotid artery (in neck)– Heart
Blood Tests for Stroke • Blood glucose (for diabetes and low sugar)• Cholesterol• Full blood count
– Anaemia (low haemoglobin) or polycythemia (too many red cells)
– White cells (? Infection)– Platelets (? Too many or too few)
• Electrolytes (e.g. sodium and potassium)• Urea and creatinine (kidney function and hydration)• ESR (for inflammation)• Blood clotting (for haemorrhagic stroke)
Other tests
• Chest X-ray (heart size, lungs)
• Electrocardiogram (ECG)
• Some patients may have carotid Dopplers (to look for narrowing of carotid artery)
• Some patients may have echocardiography (i.e. ultrasound of the heart) to look for blood clot in heart and abnormalities of the heart valves)