Stroke Flashcards
What are the 4 types of haemorrhagic stroke?
Haemorrhagic = 15%
Primary intracerebral haemorrhage:
- hypertension
- amyloid angiopathy
Secondary intracerebral haemorrhage:
-AVN
Aneurysm
Tumour
What are the 4 types of ischaemic stroke?
Ischaemic = 85%
Atherothrombosis: thrombus lodges in a cerebral artery from another location (white thrombus - platelet dependant)
Cardioembolic (red thrombus - slow blood flow)
Small vessel disease
Large vessel atherosclerosis
-usually acute on chronic with series of TIAs
What score can be used if stroke is suspected?
Rosier score:
-Has there been loss of consciousness or syncope (yes = -1)
Has there been seizure activity (yes = -1)
Is there a new onset (or waking from sleep) of:
Asymmetric facial weakness (y = +1)
Asymmetric arm weakness (Y=+1)
Asymmetric leg weakness (Y= +1)
Speech disturbance (Y = +1)
Visual field defect (Y = +1)
Stroke is likely if total score > 0
Scores of < / = 0 have low probability of stroke but not excluded
What is the 4 parts to the diagnosis of stroke?
Type of stroke – haemorrhagic or ischaemic?
CT scan differentiates
Size of stroke – oxford classification: TACS/PACS/LACS/LACS/POCS
Laterality of stroke – right or left side of brain
- Dominant hemisphere (if left handed is right hand side) – cortical events often affect language and rehab is difficult
- Non-dominant hemisphere cortical events affect spatial awareness
Cause of stroke
What is TACS?
Total anterior circulation syndrome = Large area of cortex
Comprises 20% of strokes with new onset of:
- Hemiplegia involving at least two of face, arm and leg +/- hemisensory loss
- Homonymous hemianopia
- Cortical signs (higher cortical dysfunction – language/neglect)
- Most severe type of stroke with only 5% alive and independent at 1year
What is PACS?
Partial anterior circulation syndrome =Cortex much less involved
Comprises 30% strokes and have to have 2 out of 3 features present in TACS or:
Isolated cortical dysfunction such as dysphasia
Or
Pure motor/sensory signs less severe than in lacunar syndromes e.g. monoparesis
About 55% patients alive and independent at 1 year
What is LACS?
Small infarct:
25% strokes
lacunar infarcts are small infarct in the deeper part parts of the brain and in the brainstem
- basal ganglia
- thalamus
- white matter
caused by occlusion of a single deep penetrating artery
affect to any 2 of face, arm and leg
What are the 4 main patterns of LACS?
best prognosis of all the strokes – 60% pt.s alive and independent at 1 year
4 main patterns:
- pure motor hemiparesis -hemisensorimotor
- ataxic hemiparesis – dysarthria and a clumsy hand
- pure hemisensory
(not all lacunar events cause lacunar syndromes)
What is POCS?
post. Circulation feeds base of brain and midbrain so range of deficits seen
25% strokes and overlap with lacunar strokes
- cranial nerve palsys
- bilateral motor and/or sensory deficits
- conjugate eye movement disorders
- isolated homonymous hemianopia
- cortical blindness
- cerebellar deficits without ipsilateral motor/sensory signs
Management of acute stroke:
- what needs to be kept within normal limits?
- should blood pressure be lowered?
- What should be given if a haemorrhagic stroke has been excluded?
- What is done regarding anticoagulation in AF
- when is a statin started?
blood glucose, hydration, oxygen saturation and temperature should be maintained within normal limits
blood pressure should not be lowered in the acute phase unless there are complications e.g. Hypertensive encephalopathy*
aspirin 300mg orally or rectally should be given as soon as possible if a haemorrhagic stroke has been excluded
-Aspirin 300 mg daily should be commenced within 48 hours of ischaemic stroke and continued for at least 14 days.
with regards to atrial fibrillation, the RCP state: ‘anticoagulants should not be started until brain imaging has excluded haemorrhage, and usually not until 14 days have passed from the onset of an ischaemic stroke’
A statin should be prescribed to patients who have had an ischaemic stroke, irrespective of cholesterol level. Many physicians will delay treatment until after at least 48 hours due to the risk of haemorrhagic transformation
What thrombolysis can be used and when is this used?
Thrombolysis should only be given if:
it is administered within 4.5 hours of onset of stroke symptoms (unless as part of a clinical trial) haemorrhage has been definitively excluded (i.e. Imaging has been performed)
rt-PA is used
What are absolute contraindications to thombolysis?
- Previous intracranial haemorrhage
- Seizure at onset of stroke
- Intracranial neoplasm
- Suspected subarachnoid haemorrhage
- Stroke or traumatic brain injury in preceding 3 months
- Lumbar puncture in preceding 7 days
- Gastrointestinal haemorrhage in preceding 3 weeks
- Active bleeding
- Pregnancy
- Oesophageal varices
- Uncontrolled hypertension >200/120mmHg
What are relative contraindications to thrombolysis?
- Concurrent anticoagulation (INR >1.7)
- Haemorrhagic diathesis
- Active diabetic haemorrhagic retinopathy
- Suspected intracardiac thrombus
- Major surgery / trauma in preceding 2 weeks
What imaging is used in suspected stroke?
CT scanning is recommended for most patients in the acute
phase of stroke.
MRI with diffusion weighted and gradient echo sequences is
recommended
(where available and practical) for the diagnosis
of acute stroke syndromes in patients who:
are not severely ill, especially where either neurological
deficit is mild and the clinical likelihood is that the lesion is
small or lies in the posterior fossa
present late (after one week)
What investigations are used in stroke?
Full lipid profile
Blood pressure Carotid scan – identify and quantify carotid artery stenosis, may detect a dissection Blood pressure ECG Consider 24hour ECG (or longer) echo-cardiogram – possible embolic source of stroke
