Stroke therapy Flashcards
Every minute in which a large vessel ischaemic stroke is untreated, how much of the brain is lost?
- 9 million neurons
- 8 billion synapses
12 km of axonal fibres
When does thrombolysis become more harmful for stroke treatment than beneficial?
4.5 hours
What are the risk factors for haemorrhage due to thrombolysis for stroke therapy?
Infarct size Vessel occlusion Diabetes Blood pressure Age Stroke severity Tissue changes Antiplatelets
What are predictors for Significant symptomatic intracerebral haemorrhage?
age glucose stroke severity hyperdense middle cerebral artery on CT scan ASPECTS score anti-platelet therapy.
What thrombolytic agent is commonly used to treat stroke?
Alteplase
What are the practicalities of fast treatment of stroke?
Call for help
Alert hospital team
Alert CT/radiology team
Keeping the patient + relatives informed
Why is pre-hospital notification of a stroke patient by an incoming ambulance beneficial?
Reduces average door to review time
Reduces average door to CT scan time
Reduces average door to needle time
What interventional procedure can be done alongside IVT (thrombolysis)?
Thrombectomy
What does rTPA mean?
recombinant tissue plasminogen activator - thrombolytic agents
eg Alteplase, reteplase
Whats better, IVT with thrombectomy or just IVT?
IVT + thrombectomy
When would you not use thrombolysis to treat a stroke?
If it’s a haemorrhagic stroke
What are the contraindications to thrombolysis?
Age > 80 Hypertensive (even if controlled with drugs) Time of onset is >4 hours Severe stroke Stroke in the past 3 months Seizure Symptoms suggestive of sub-arachnoid haemorrhage Warfarin or Heparin History of prior stroke and concomitant diabetes Platelet count <100,000 Hypoglycaemia or hyperglycaemia Haemorrhagic diathesis (tendancy)
What aspects of a past medical history would you check before thrombolysis started?
Prior stroke (within last 3 months)
Intracranial haemorrhage
Other episode of severe/dangerous bleeding
Concomitant Diabetes
Haemorrhagic diathesis
Hypertension
What is the first line investigation for stroke?
Urgent CT
What scale is commonly used to grade a stroke patient?
NIHSS
Goes up to 42 I think (most severe)
What is a Hemicraniectomy?
Surgical decompression of brain by removing part of the skull overlying the oedematous section of the brain
Used to treat cerebral oedema which can happen to people with strokes
When should Hemicraniectomy be performed?
For individuals aged up to 60 years who suffer an acute Middle Cerebral Artery territory ischaemic stroke complicated by massive cerebral oedema, surgical decompression by hemicraniectomy should be offered within 48 hours of stroke onset
Aside from thrombolysis, what other agent should be given to patients with acute stroke?
Aspirin
What part of the past medical history puts someone most at risk of having a stroke?
Having a previous stroke
What other cerebrovascular event increases the risk of stroke, and by how much?
TIA
1/3rd of people who have a TIA will have an acute stroke
Why is early treatment of TIA/minor stroke important?
Early initiation of preventative treatment can reduce the risk of early recurrent stroke by 80%.
For patients with a TIA, evaluation and initiation of treatment in a specialised outpatient clinic is associated with a reduced risk of subsequent stroke
What drugs are used in secondary prevention of another stroke?
Clopidogrel 75 mg
Or
Aspirin 75mg + dipyridamole MR 200mg bd
Statin
Blood pressure drugs, even if blood pressure in normal range
What procedure can be carried out for secondary prevention of stroke?
Carotid endarterectomy
How much does a carotid endarterectomy reduce the risks associated with stroke?
50-69% stenosis: risks of stroke or death reduced by 7-9% at 5 years after surgery
> 70% stenosis: risks of stroke or death reduced by 14-19% at 5 years after surgery
What are the indications for a carotid endarterectomy?
Anterior circulation
TIA or stroke with
good recovery
70% occlusion