Stroke Flashcards
What is a stroke?
Occurs when the blood supply to part of the brain is cut off.
What are the main types of stroke?
Ischaemic.
Haemorrhagic.
Transient ischaemic attack (TIA).
What are the symptoms of stroke?
Face:
Dropped on 1 side.
Person may not be able to smile.
Mouth or eye may have dropped.
Arms - unable to lift both arms & keep them there.
Speech:
May be slurred or garbled.
May not be able to talk at all.
May also have problems understanding what you’re saying to them.
Time – time to dial 999.
How would you determine the severity of a stroke?
NIHSS score:
Score Stroke Severity
0 No stroke symptoms
1 - 4 Minor stroke
5 - 15 Moderate stroke
16 - 20 Moderate to severe stroke
21 - 42 Severe stroke
What imaging would be used for TIAs?
MRI - consider post TIA assessment by specialist.
CAROTID - if considered to be a candidate for carotid endarterectomy post TIA assessment.
Specialist unit Brian Imaging for acute stroke.
CT - for acute stroke.
CT is sensitive to the intracranial blood and is readily available. Therefore, CT rules out hemorrhagic stroke.
However, CT Scan changes in ischemic stroke may take several days to develop.
MRI may be a better option.
What is initial TIA management?
Aspirin 300mg.
TIA referral.
Don’t use ABCD2 as risk of stroke tool.
Start secondary prevention in addition to aspirin.
What is the treatment for acute ischaemic stroke?
Alteplase < 4.5hrs.
Thrombectomy.
Aspirin 300mg po/pr 2/52.
Start people on long-term treatment earlier if they are being discharged before 2 weeks.
PPI + aspirin if previous dyspepsia associated with aspirin is reported.
Offer alternative antiplatelet agent if allergic/ genuinely intolerant of aspirin.
Not routinely anticoagulated.
How would you treat haemorrhagic stroke?
Return clotting levels to normal asap if PIH + previous warfarin.
Use a combination of prothrombin complex concentrate and intravenous vitamin K.
DOACs.
What are some anticoagulation treatment options for other comorbidities?
Atrial fibrillation.
Prosthetic valves.
Ischaemic stroke and symptomatic proximal DVT or PE.
Haemorrhagic stroke and symptomatic DVT or PE.
How would you control blood pressure for people with acute ICH?
Rapid blood pressure lowering :
Present within 6 hours of symptom onset and
have a systolic blood pressure over 150 mmHg.
Aim for systolic blood pressure t of 130 to 140 mmHg within 1 hour of starting treatment and maintain this blood pressure for at least 7 days.
DO NOT offer rapid blood pressure lowering:
- underlying structural cause (e.g. tumour, arteriovenous malformation, aneurysm)
- Glasgow Coma Score of below 6
- going to have early neurosurgery to evacuate the haematoma
- have a massive haematoma with a poor expected prognosis.
What would you give to control blood pressure for people with acute ICH?
Aged 55 or over /African or Caribbean at any age:
Start with a long-acting dihydropyridine calcium channel blocker or a thiazide-like diuretic.
Add angiotensin converting enzyme inhibitor (ACEI) or angiotensin II receptor blocker (ARB) if target blood pressure is not achieved.
If not of African or Caribbean origin and younger than 55 years:
Start with ACEI or an ARB.
When should you consider statin treatment?
Immediate initiation of statin treatment is not recommended in people with acute stroke.
Continue statin treatment in people with acute stroke who are already receiving statins.
What blood glucose concentration should be maintained in people with acute stroke?
Maintain a blood glucose concentration between 4 and 11 mmol/litre in people with acute stroke.
Why is stroke so damaging to the brain?
The brain is a very high maintenance organ and requires constant supply of oxygen and glucose.
Oxygen and glucose are delivered to the brain through brain vasculature.
Smallest insult to our brain vasculature will have tremendous effect on brain metabolism and function leading to severe damage and possible death.
What is a transient ischaemic attack (TIA)?
Temporary focal neurological deficit of sudden onset caused by ischemia of the brain, spinal cord or retina lasting less than 24 hours followed by complete recovery.
New definition: No objective evidence of acute infarction in the affected region of brain or retina; < 1 hour.
What are some modifiable factors for ischemic stroke?
Major:
Hypertension. Heart disease, esp. atrial fibrillation. Cigarette smoking. Transient ischemic attacks. Dyslipidaemia. Physical inactivity. Obesity.
Less well documented:
Excessive alcohol intake.
Drug abuse.
Acute infection.
What are some non-modifiable factors for ischemic stroke?
Major:
Prior stroke/ transient ischemic attack.
Increased age.
Being male.
Race (e.g African- Americans).
Diabetes.
Family history of stroke.
Asymptomatic carotid bruit (systolic noise).
Genetic factors:
Apolipoprotein E4.
Elevated Homocysteine labels.
Factor V mutation.
What are the warning signs of stroke?
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.
What is atherosclerosis?
Potentially serious condition where arteries become clogged with fatty substances called plaques, or atheroma.
What is thromboembolism?
Thromboembolism is the name for when a blood clot (thrombus) that forms in a blood vessel breaks loose, is carried by the bloodstream, and blocks another blood vessel. This is a dangerous condition that can affect multiple organs, causing organ damage and even death.
What is the surgical management of stroke?
For Ischemic stroke:
Endovascular interventions: angioplasty and stenting, mechanical clot disruption, clot extraction.
Carotid endarterectomy.
EC/IC bypass surgery.
For intracranial haemorrhage: surgical evacuation of haematoma.
For subarachnoid haemorrhage: clipping and coiling of aneurysm.
Surgical decompression of cerebellar haematoma.
What supportive care should be provided to an acute stroke patient?
Maintenance of adequate tissue oxygenation: protecting the airway, O2 inhalation.
Maintaining optimal blood pressure (autoregulation faulty or lost in stroke patients).
Management of blood glucose abnormalities (hyperglycaemia associated with poorer prognosis).
Management of fever and infections (ischemia worsened by hyperthermia, improved by hypothermia).
What is the treatment of thrombolysis?
Alteplase and streptokinase:
Plasminogen activators that increase plasmin level; a potent serine protease involved in the dissolution of fibrin blood clots
Patient profile:
Normal CT scan.
BP <180/100 mmHg.
No bleeding tendency.
Reduced morbidity by 30%.
Risk: Intracranial haemorrhage in 6% of patients.
When should you give anticoagulants?
If hemiplegia is dense, commence subcutaneous heparin 5,000 units every 12 or 8 hours.
Low dose subcutaneous low-molecular-weight heparin or unfractionated heparin may be considered for prevention of deep vain thrombosis (DVT) in patients with intracerebral haemorrhage after 4 days from onset.
What is the mechanism of action of anticoagulants?
During the clotting cascade, a chain of precursor proteins (denoted by roman numerals) activate one another to amplify clotting.
Heparin catalyses the binding of antithrombin II (ATII) to these proteins.
This inactivates these clotting proteins.
Why are antiplatelets used to treat ischemic stroke?
Aspirin within 48hrs reduces risk of mortality/ disability in ischemic stroke.
Antiplatelets contraindicated in haemorrhagic stroke.
