Term
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Definition
| Neurological deficit resulting from a non-traumatic vascular event. This may be iscahemic (thrombotic event, ischaemia) or haemorrhagic (intracranil/ subarachnoid) |
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Term
| What is the defining difference between a stroke and a TIA? |
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Definition
| TIA symptoms last less than 24 hours. |
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Term
| List the 5 cardinal faetires of stroke |
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Definition
| Sudden onset, focal symptoms, negative clinical phenomena, identifiable vascular risk factors and symptoms relate to arterial anatomy (although not in venous stroke). |
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Term
| Describe FAST as a recognition tool for stroke. |
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Definition
F- has the face fallen on one side?
A- Can both arms be raised and supported?
S- Speech slurred?
T- Treat as an emergency. |
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Term
| Asymmetric facial, grip, arm and leg weakness, speech disturbacne and visual disturbance are all positive indicators in what stroke assessment scale? |
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Definition
| ROSIER- Recognition of stroke in the emergency room. |
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Term
| What 2 factors are negative indicators of stroke when using the ROSIER scale? |
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Definition
| Loss of conciousness/syncope and any seizure activity. These signs indicate towards an alternative pathological cause of illness. |
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Term
| What 4 S's must be ruled out as differentials of Stroke? |
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Definition
| Seizure, syncope, sepsis and somatisisation. |
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Term
| When might a headache appear as a feature of stroke? |
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Definition
| Venous thrombisis or haemorrage |
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Term
| When might loss of conciousness appear as a feature of stroke? |
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Definition
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Term
| In the occurence of hemi-plegia following sroke, what would you expect to find in the limbs? |
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Definition
| Initially limbs as flaccid and areflexic but become hypereflexic and less weak. |
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Term
| What area is affected in a lacunar stroke? |
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Definition
| Areas supplied by the lenticulostriate arteries (off the middle cerebral artery). Thes include internal capsule strokes and pons, hypothalamis and thalamus. |
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Term
| Hemianaesthesia of the lower limbs is suggestive of stroke in which territory? |
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Definition
| Anterior communicating artery |
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Term
| Hemianaesthesia of the head and upper body is suggestive of stroke in which territory? |
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Definition
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Term
| Define Homonymous Hemianopia |
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Definition
| Loss of vision in one or both eyes, a sign of middle cerebral artery stroke. |
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Term
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Definition
| Impaired expression through spoken or written language |
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Term
| What is Wernickes aphasia? |
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Definition
| Impaired comprehension of language, heard or written. |
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Term
| Name three features of Anterior communicating artery strokes |
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Definition
Contralateral hemiplegia
Contralateral hemianaesthesia
Language dysfunction |
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Term
| Name two features of an internal capsule stroke |
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Definition
| Pure motor hemiplegia and pure sensory hemiplegia |
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Term
| Bilateral visual loss/diplopia, amnesia, dysarthria, unsteadiness and dysphagia are all signs of what strokes? |
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Definition
| Posterior circulation strokes |
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Term
| What are the two defining features of a venous stroke? |
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Definition
| Dont respect arterial boundaries causing mixed symptoms. Cerebral oedema, due to backing up of blood. |
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Term
| Thunderclap headache, stiff neck and raised intercranial pressure are all features of what? |
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Definition
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Term
Using the listed features, how would you differentiate between a TACI (total anterior circulation infarct) and a PACI (partial anterior circulation infarct)
New disturbance of higher cerebral function (e.g. dysphasia)
Hemianopia
Severe motor weakness of at least two areas |
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Definition
TACI- All three features must be present.
PACI- 2 of 3 features must be present, may also present with just higher function disturbance, or a pure motor/sensory defect not as severe as in a LACI. |
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Term
| In a suspected stroke patient, why would you perform and ECG? |
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Definition
| To lookf for AF/ cardiomyopathy |
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Term
| How do you acutely treat an ischaemic stroke? |
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Definition
Thrombolysis using recombinant tissue plasminogen activator, most beneficial within 3 hours of onset.
Antiplatelets and aspirin reduces further stroke risk. |
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Term
| How do you acutely treat a haemorrhagic stroke? |
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Definition
Rapid lowering of BP.
?Surgical intervention to stop the bleed? |
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Term
| How do you acutely treat a venous stroke? |
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Definition
| Anticoagulation with heparin and long term warfarin. Direct thrombolysis with a microcatheter and surgical thrombus removal should also be considered. |
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Term
| What two long term treatments should be considered for all strokes and what additional treatment should be considered for embolic and venous strokes? |
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Definition
All strokes- antiplatelet (aspirin/clopidogrel) and rehab.
Embolic/venous strokes- Antocoagulant therapy (heparin ->warfarin) |
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Term
| What are the risk factors for venous stroke? |
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Definition
| Pregnancy, oestrogen (OCP), hypercoagulability and infection. |
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Term
| The anterior circulation of the brain is supplied by the 2 internal carotid arteries. What cerebral arteries are included in this circulation and what do they supply? |
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Definition
Anterior cerebral arteries - supply medical 2 frontal lobes
Anterior communicating artery
Middle Cerebral Arteries- lateral, frontal and anterior temporal lobes |
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Term
| The posterior circulation of the brain, supplied by the vertebral arteries via the basilar arteries includes what vessels? |
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Definition
Posterior cerebral arteries- supply posterior temporal lobes and occipital lobes
Posterior communicating arteries- Provide a link between anterior and posterior circulation. |
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Term
| What is the importance of controlling cerebral blood flow? |
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Definition
| Supply more blood to ares with increased metabolic demand and maintain a constant blood pressure in the brain. |
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Term
| How is regional variation of blood flow achieved in the brain? |
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Definition
| Increased metabolic rates in the brain result in varied arterial tone therefore resulting in increased blood supply to areas with a higher metabolic rate. |
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Term
| Cerebral blood flow is kept between what pressures? |
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Definition
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Term
| What myogenic response auto regulates cerebral blood flow? |
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Definition
| Vascular smooth muscle contraction in response to increased blood pressure. |
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Term
| What endothelial response auto regulates cerebral blood flow? |
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Definition
| Production of nitric oxide by cells in response to increased shear stresses. This increases blood flow and decreses vascular resistance. |
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Term
| What factors reduce the ability to autoregulate cerebral blood flow? |
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Definition
| Age, Head Trauma, SAH, CVA or Cerebral Hypoxia, High pCO2 and Chronic Hypertension – May lead to ‘range’ being reset (e.g. maintenance of CBF between BPs of 90 & 210) |
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Term
| Failure to autoregulate cerebral blood flow results in what? |
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Definition
| Cerebral blood flow varying with systemic blood pressure. Therefore increased Bp-> cerebral oedema and encephalopathy and decreased Bp-> blackouts, cerebral hypoxia and ischaemic stroke. |
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Term
| What is the role of a glial cell and how do they metabolise? |
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Definition
| Support cells, they maintain homeostasis, make myelin and supply surrounding cells with lactate. They metabolise both aerobically and anaerobically. |
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Term
| How do neurons metabolise? |
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Definition
| Obligate anaerobes, can metabolise glucose but mostly metabolise lactates from neighbouring glia. |
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Term
| Global ischaemia results in what and can be caused by what? |
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Definition
| Results of an interruption of circulation and reduction in general perfusion. Can be caused by cardiac arrest, severe hypotension and/or shock |
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Term
| Considering aerobic potential, what pathological changes would you expect to find with global ischemia? |
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Definition
| Neuronal necrosis and cortical laminar necrosis, neurons lost in a laminar pattern due to aerobic dependence. |
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Term
| Describe a water shed infarct |
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Definition
| Occur at watersheds between arterial supplies due to reduced blood flow at distal ends and therefore increased susceptibility to infarcts. |
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Term
| In a brief global ischaemia what would you expect clinically? |
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Definition
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Term
| What clinical outcome would you expect from a ischemia only infarcting certain areas? |
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Definition
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Term
| With brain death resulting from a non perfused brain, what would you expect clinically? |
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Definition
| Oedema causing raised intercranial pressure |
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Term
| What are the clinical features of a transient ischaemic attack (TIA)? |
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Definition
| Rapid onset, focal dysfunction and duration of under 24 hours |
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Term
| TIA increases your risk of what? |
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Definition
| Stroke (7-10%) and MI (7%) |
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Term
| In a cerbrovascular accident (CVA) what is the prognosis? |
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Definition
| 50% good recovery, 50% permanent loss of function |
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Term
| Ischaemic strokes account for 80% of CVA's, but what causes them? |
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Definition
| Atherosclerosis, vasculitis, emboli, primary vascular disorders and hypercoagulable states. |
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Term
| Where must a haemorrhage be in order for it to be considered a CVA? |
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Definition
| Suarachnoid, therefore subdural and epidural do not count. |
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Term
| What causes an intracerebral haemorrhage and where do they most commonly occur? |
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Definition
Ateriosclerosis/aneurysms of small arterioles rupture and bleed, Hypertension, major predisposing factor.
Most commonly found in thalamus/basal ganglia |
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Term
| What is the most common cause of subarachnoid haemorrhage? |
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Definition
| Rupture of saccular aneurysm in anterior circle of willis. |
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Term
| What investigations would you use to diagnose a venous stroke |
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Definition
| CT Venography, D Dimer or clotting assays. |
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Term
| Whats the first line treatment for a venous stroke? |
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Definition
| Anti-coagulation even in the presence of haemorrhage allowing for a relief of back pressure. |
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Term
| Without significant effect from anti coagulation, what should be the next line of treatment in a venous stroke? |
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Definition
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Term
| What treatment would you consider in order to relieve intra-cranial pressure? |
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Definition
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