Stroke and TIAs Flashcards by Aimee Taylor

How is blood supplied to the front of the brain?

Blood travels from the aorta into the left and right carotid arteries, then into the left and right anterior cerebral arteries and then into the middle cerebral arteries

How well did you know this?

Not at all

Perfectly

What is the anterior cerebral artery?

A major artery in the brain that supplies oxygenated blood to the frontal lobe, parietal lobe and corpus callosum

How well did you know this?

Not at all

Perfectly

What does the middle cerebral artery do?

Supplies oxygenated blood to the brain’s parietal and temporal lobes as well as deeper

How well did you know this?

Not at all

Perfectly

How is blood supplied to the back of the brain?

Blood goes from the aortic arch, into the right and left subclavian arteries. These turn into the left and right vertebral arteries which form to meet the basilar artery which breaks into the right and left posterior cerebral arteries

How well did you know this?

Not at all

Perfectly

What does the posterior cerebral artery do?

Supplies blood to the occipital lobe and brain stem

How well did you know this?

Not at all

Perfectly

What does the posterior communicating artery do (circle of willis)?

Connects the brain’s anterior and posterior circulations, providing blood to the brain allowing for collateral circulation. Offers alternative ways for blood to get around obstructions

How well did you know this?

Not at all

Perfectly

What is collateral circulation?

A network of backup blood vessels that can take over when another artery or vein is damaged or blocked

How well did you know this?

Not at all

Perfectly

What is a stroke?

A stroke is a medical emergency that occurs when the blood supply to a part of the brain is interrupted or reduced depriving brain tissue of oxygen and nutrients, this causes brain cells to begin dying within minutes

How well did you know this?

Not at all

Perfectly

What are the 2 types of stroke?

Ischemic and haemorrhagic

How well did you know this?

Not at all

Perfectly

What are the types of ischemic stroke?

Thrombotic, embolic, systemic

How well did you know this?

Not at all

Perfectly

What are the types of haemorrhagic stroke?

Subarachnoid haemorrhage
Intracerebral haemorrhage

How well did you know this?

Not at all

Perfectly

What is a thrombus?

A blood clot that forms in a vein or artery

How well did you know this?

Not at all

Perfectly

What is an embolus?

A thrombus that breaks free and travels to another part of the body (AF, DVT)

How well did you know this?

Not at all

Perfectly

What is systemic?

Gross reason for decrease blood to the brain (cardiac arrest, MI, shock)

How well did you know this?

Not at all

Perfectly

How does an ischemic stroke develop?

Blockage of an artery occurs
No blood flow means cells do not receive glucose and oxygen
This leads to a build up of sodium and calcium
Sodium causes water to come into the cell leading to swelling
Calcium causes damage to mitochondria and lysosomes, this leads to release of apoptosis factors and degradative enzymes
Immune cells then take damaged cells away causing inflammation
The inflammation damages the blood brain barrier and proteins to get into the brain tissue, this causes swelling
This pressure causes the brain to push to the unaffected side and can also push to the base of the skull, affecting breathing and consciousness

How well did you know this?

Not at all

Perfectly

What is Apoptosis?

A process of programmed cell death that occurs in multicellular organisms and some single-celled microorganisms

How well did you know this?

Not at all

Perfectly

What are degradative enzymes?

Proteins that break down biological molecules

How well did you know this?

Not at all

Perfectly

What is penumbra?

An area of viable tissue

How well did you know this?

Not at all

Perfectly

What is a haemorrhagic stroke?

A stroke caused by a ruptured artery within the brain

How well did you know this?

Not at all

Perfectly

When does a haemorrhagic stroke occur?

When a blood vessel in the brain ruptures, leading to bleeding in or around the brain, this disrupts normal blood flow causing direct damage to brain tissues and increasing intracranial pressure

What is intracerebral haemorrhage?

Bleeding occurs within the brain

What is subarachnoid haemorrhage?

Bleeding occurs in space between inner and outer layers of tissue that surround the brain

How does a haemorrhagic stroke develop - intacerebral haemorrhage?

Blood vessel ruptures
Intracerebral haemorrhage occurs due to hypertension
Blood leaks into brain tissue
Increasing pressure in the brain tissue, blood vessels and skull
any vessels downstream of this pressure are then starved of blood leading to ischemia
The pressure can cause brain herniation (movement of brain tissue) into the only space it can

What is the fax cerebri?

A sickle-shaped fold of dura mater that separates the two cerebral hemispheres of the brain

What is the tentoriuym cerebelli?

an invagination of the meningeal layer of the dura mater that separates the occipital and temporal lobes of the cerebral hemispheres from the cerebellum and brainstem

What is the foramen magnum?

A large opening that connects the brain to the spinal cord

How does a hemorrhagic stroke develop - subarachnoid haemorrhage?

1. Blood vessel ruptures due to aneurysm of trauma 2. Bleeding occurs in the subarachnoid space 3. Bleeding leaks into brain tissue 4. increased pressure in brain tissue, blood vessels and the skull 5. Any vessels downstream of this pressure are then starved of blood, leading to schema

What is Cushing's triad?

A physiological response to increased intracranial pressure that occurs when the nervous system attempts to compensate for diminished cerebral perfusion

What are the 3 elements of Cushing's triad?

Hypertension Bradycardia Irregular respirations

Why does hypertension occur when there is an increased intracranial pressure?

The sympathetic nervous system is activated to maintain cerebral perfusion which increases BP

Why does bradycardia occur when there is an increase in intracranial pressure?

Parasympathetic nervous system is activated due to the increase in BP which slows the heart rate

Why do irregular respirations occur when there is an increase in intracranial pressure?

Increased ICP may put pressure on the brainstem which can lead to dysfunction of the respiratory centre

What are the differences between and ischaemic and haemorrhagic stroke?

Ichaemic: Most common, usually caused by atherosclerosis, prolonged aetiology, may be associated with heart condition, long history of vessel disease Haemorrhagic: Less common, usually the result of cerebral aneurism, sudden aetiology, commonly develops during exercise or stress, may be asymptomatic prior to rupture, may be associated with cocaine use

What is a TIA?

Cerebral ischaemia that does not inflict any permanent damage - rarely last longer than 1-2 hours

What are the differences between and stroke and TIA?

Stroke: Effects can be irreversible, life threatening, life altering, ischaemic cells post 5 mins die TIA: temporary occlusion of a vessel, scribed as angina of the brain, precursor for a stroke, symptoms rarely last longer than 1-2 hours, intermittent short episodic symptoms

What is the pre-hospital treatment for a stroke?

ABCD Aspirin

What are the modifiable risk factors for a stroke?

diabetes, high cholesterol, smokings, drug abuse, hypertension, MI, AF, oral contraceptive use, poor diet

What are the unmodifiable risk factors for a stroke?

Age, genetics, gender, previous stroke, previous TIA, race

What is arteriosclerosis?

Hardening of arteries (smaller arteries and arterioles specifically) occurs over time

What is atherosclerosis?

Plaque build up consisting of fibrin, lipids and cell debris common at the site of bifurcation of an artery and usually associated with major arteries such as carotid and coronary arteries

What is macroangiopathy?

Damage in larger arteries causing atherosclerosis

What is microangiopathy?

Causes damage in the capillaries

What are some of the general stroke symptoms?

Facial droop, one sided limb weakness, confusion, visual disturbance, incontinence, vomiting, ataxia, aphasia or dysphasia, aphasia or dysphagia

What is aphasia?

Loss of the power of speech

What is aphagia?

inability to swallow

What is dysphagia?

Difficulty in swallowing

What is dysphasia?

abnormal speech hard to understand

What things can mimic a stroke?

Hypoglycaemia, hypoxia, hypotension, hypothermia, fitting, toxins, sedatives or alcohol, Bell's palsy