Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Y4 Neurology and Special Senses: Neurology > Stroke > Flashcards

Stroke Flashcards

1
Q

What is a stroke?

A

Stroke is defined as an acute neurological deficit lasting more than 24 hours and caused by cerebrovascular aetiology.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How are strokes subdivided?

A

Cerebrovascular accidents are either:

  • Ischaemia or infarction of brain tissue secondary to inadequate blood supply
  • Intracranial haemorrhage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which type of stroke is most common? Ischemic stroke or haemorrhagic stroke?

A

Ischaemic stroke accounts for 87% of all strokes, haemorrhagic stroke for 10% and subarachnoid haemorrhage for 3%.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Briefly recap the Circle of Willis

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What can cause a distruption of the blood supply in the brain?

A

Disruption of blood supply can be caused by:

  • Thrombus formation or embolus, for example in patients with atrial fibrillation
  • Atherosclerosis
  • Shock
  • Vasculitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a transient ischaemic attack (TIA)?

A

Transient ischaemic attack (TIA) was originally defined as symptoms of a stroke that resolve within 24 hours. It has been updated based on advanced imaging to now be defined as transient neurological dysfunction secondary to ischaemia without infarction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a cresendo TIA? And what is the risk of this?

A

A crescendo TIA is where there are two or more TIAs within a week. This carries a high risk of developing in to a stroke.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Briefly describe an ischaemic stroke and its causes

A

Ischaemic strokes occur when the blood supply to an area of brain tissue is reduced, resulting in tissue hypoperfusion.

There are several potential mechanisms which can result in an ischaemic stroke including:

  • Embolism
    • An embolus originating somewhere else in the body (e.g. the heart) causes obstruction of a cerebral vessel, resulting in hypoperfusion to the area of the brain the vessel supplies.
  • Thrombosis
    • Ablood clot forms locally within a cerebral vessel (e.g. due to atherosclerotic plaque rupture)
  • Systemic hypoperfusion
    • Blood supply to the entire brain is reduced secondary to systemic hypotension (e.g. cardiac arrest)
  • Cerebral venous sinus thrombosis
    • Blood clots form in the veins that drain the brain, resulting in venous congestion and tissue hypoxia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Briefly describe a haemorrhagic stroke and its causes

Note: intracerebral and subarachnoid haemorrhage

A

Haemorrhagic strokes occur secondary to rupture of a blood vessel or abnormal vascular structurewithin the brain.

There are two sub-types of haemorrhagic stroke known as intracerebral haemorrhage and subarachnoid haemorrhage.

  • Intracerebral haemorrhage
    • Intracerebral haemorrhage involves bleeding within the brain secondary to a ruptured blood vessel
    • Intracerebral haemorrhages can be intraparenchymal (within the brain tissue) and/or intraventricular (within the ventricles)
  • Subarachnoid haemorrhage
    • Subarachnoid haemorrhage is a type of stroke caused by bleeding outside of the brain tissue, between the pia mater and arachnoid mater
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What stroke is shown in the image?

A

Intracerebral haemorrhage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What stroke is shown in the image?

A

Subarachnoid haemorrhage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What stroke is shown in the image?

A

Ischaemic stroke specifically total anterior circulation stroke (TACS).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Briefly describe the blood flow to the cerebrum

A

The anterior, middle and posterior cerebral arteries each supply a specific territory of the brain:

  • The anterior cerebral arteries supply the anteromedial area of the cerebrum
  • The middle cerebral arteries supply the majority of the lateral cerebrum
  • The posterior cerebral arteries supply a mixture of the medial and lateral areas of the posterior cerebrum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Briefly describe the Bamford classification system for strokes

A

The most commonly used classification system for ischaemic stroke is the Bamford classificationsystem (also known as the Oxford classification system).

This system categorises stroke based on the initial presenting symptoms and clinical signs. This system does not require imaging to classify the stroke, instead, it is based on clinical findings alone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 4 types of ischaemic strokes according to the Bamford classification system?

A
  1. Total anterior circulation stroke (TACS)
  2. Partial anterior circulation stroke (PACS)
  3. Posterior circulation syndrome (POCS)
  4. Lacunar stroke (LACS)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does a total anterior circulation stroke (TACS) present?

A

A total anterior circulation stroke (TACS) is a large cortical stroke affecting the areas of the brain supplied by both the middle and anterior cerebral arteries.

All three of the following need to be present for a diagnosis of a TACS:

  • Unilateral weakness (and/or sensory deficit) of the face, arm and leg
  • Homonymous hemianopia
  • Higher cerebral dysfunction (dysphasia, visuospatial disorder)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How does a partial anterior circulation stroke (PACS) present?

A

A partial anterior circulation stroke (PACS) is a less severe form of TACS, in which only part of the anterior circulation has been compromised.

Two of the following need to be present for a diagnosis of a PACS:

  • Unilateral weakness (and/or sensory deficit) of the face, arm and leg
  • Homonymous hemianopia
  • Higher cerebral dysfunction (dysphasia, visuospatial disorder)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does posterior circulation syndrome (PCOS) present?

A

A posterior circulation syndrome (POCS) involves damage to the area of the brain supplied by the posterior circulation (e.g. cerebellum and brainstem).

One of the following need to be present for a diagnosis of a POCS:

  • Cranial nerve palsy and a contralateral motor/sensory deficit
  • Bilateral motor/sensory deficit
  • Conjugate eye movement disorder (e.g. horizontal gaze palsy)
  • Cerebellar dysfunction (e.g. vertigo, nystagmus, ataxia)
  • Isolated homonymous hemianopia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does a lacunar stroke (LACS) present?

A

A lacunar stroke (LACS) is a subcortical stroke that occurs secondary to small vessel disease. There is no loss of higher cerebral functions (e.g. dysphasia).

One of the following needs to be present for a diagnosis of a LACS:

  • Pure sensory stroke
  • Pure motor stroke
  • Sensori-motor stroke
  • Ataxic hemiparesis
20
Q

Briefly recap the Bamford classification system of ischaemic strokes

A
21
Q

What are the clincial features of a stroke?

A

In neurology, suspect a vascular cause where there is a sudden onset of neurological symptoms.

Stoke symptoms are typically asymmetrical:

  • Sudden weakness of limbs
  • Sudden facial weakness
  • Sudden onset dysphasia (speech disturbance)
  • Sudden onset visual or sensory loss
22
Q

What are the risk factors for strokes?

A
  • Cardiovascular disease such as angina, myocardial infarction and peripheral vascular disease
  • Previous stroke or TIA
  • Atrial fibrillation
  • Carotid artery disease
  • Hypertension
  • Diabetes
  • Smoking
  • Vasculitis
  • Thrombophilia
  • Combined contraceptive pill
23
Q

Briefly describe the FAST tool for identifying strokes in the community

A

F – Face

A – Arm

S – Speech

T – Time (act fast and call 999)

24
Q

Briefly describe the ROSIER (Recognition of Stroke in the Emergency Room) in the emergency department tool for idenfitying a stroke

A

ROSIER is a clinical scoring tool based on clinical features and duration. Stroke is likely if the patient scores anything above 0.

25
Q

How is a stroke diagnosed?

A

Use the CT scan to differentiate between ischaemic stroke and haemorrhagic stroke; which must be done before starting thrombolysis in ischaemic stroke and before reversing anticoagulation in anticoagulation-induced intracerebral haemorrhage.

Ischaemic stroke is a clinical diagnosis based on signs and symptoms. A normal CT scan does not rule out a stroke but will rule out intracranial haemorrhage, which must be excluded before starting thrombolysis.

26
Q

What investigations should be ordered for a stroke?

A
  • Non-ontrast CT head
  • Serum glucose
  • Serum electrolytes
  • Serum urea and creatinine
  • Cardiac enzymes
  • FBC
  • ECG
  • Prothrombin time and PTT (with INR)
27
Q

Why investigate using non-contrast CT head?

A

Request an immediate non-enhanced CT of the head (i.e. ideally in the next available time slot and definitely within 1 hour).

Use the CT scan to differentiate between ischaemic stroke and haemorrhagic stroke; which must be done before starting thrombolysis in ischaemic stroke and before reversing anticoagulation in anticoagulation-induced intracerebral haemorrhage.

28
Q

Why investigate blood glucose?

A

Hypoglycaemia is a stroke mimic; hyperglycaemia has been associated with intracerebral bleeding and worse clinical outcomes in patients treated with intravenous thrombolysis.

You need to exclude both before giving thrombolysis.

29
Q

Why investigate serum electrolytes?

A

To exclude electrolyte disturbance (e.g. hyponatraemia) as a cause for sudden onset neurological signs.

30
Q

Why investigate serum urea and creatine?

A

To exclude renal failure because it may be a potential contraindication to some stroke interventions.

31
Q

Why investigate cardiac enzymes?

A

To exclude concomitant myocardial infarction.

32
Q

Why investigate FBC?

A

To exclude anaemia or thrombocytopenia prior to possible initiation of thrombolysis, anticoagulants, or antithrombotics.

33
Q

Why investigate using ECG?

A

To exclude cardiac arrhythmia (such as atrial fibrillation) or ischaemia, which are relatively common in ischaemic stroke.

34
Q

Why investigate prothombin time and PTT (with INR)?

A

To exclude coagulopathy.

Don’t delay thrombolysis (e.g., by waiting for test results) if the patient has no history of anticoagulant use, coagulopathy, or a condition that may lead to coagulopathy.

35
Q

Briefly describe the use of thrombolysis to treat a stroke

Note: ischaemic stroke

A

Thrombolysis with alteplase should only be given if:

  • It is administered within 4.5 hours of onset of stroke symptoms
  • Haemorrhagic stroke has been definitively excluded (i.e. imaging has been performed)
36
Q

What drug is used for thrombolysis?

A

Alteplase.

37
Q

What is the mechanism of alteplase?

A

Alteplase is a tissue plasminogen activator that rapidly breaks down clots and can reverse the effects of a stroke if given in time.

38
Q

What are the absolute contraindications of alteplase?

A
  • 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
39
Q

Briefly describe the use of thrombolysis to treat a stroke

Note: ischaemic stroke

A

Thrombectomy (mechanical removal of the clot) may be offered if an occlusion is confirmed on imaging, depending on the location and the time since the symptoms started.

It is not used after 24 hours since the onset of symptoms. Ideally should be done within 6 hours.

40
Q

What is the role of aspirin in treating a stroke?

A

Offer 300mg aspirin to everyone presenting with acute stroke who has had a diagnosis of intracerebral haemorrhage excluded by brain imaging.

Continue aspirin daily 300 mg until 2 weeks after the onset of stroke symptoms, at which time start definitive long-term antithrombotic treatment.

41
Q

Briefly describe the management of a TIA

A

Offer aspirin (300 mg daily), unless contraindicated, to people who have had a suspected TIA, to be started immediately.

Refer immediately people who have had a suspected TIA for specialist assessment and investigation, to be seen within 24 hours of onset of symptoms.

Offer secondary prevention, in addition to aspirin, as soon as possible after the diagnosis of TIA is confirmed.

42
Q

What specialist imaging can be used following a stroke?

A

The aim of imaging is to establish the vascular territory that is affected. It is guided by specialist assessment.

  • Diffusion-weighted MRI is the gold standard imaging technique
    • CT is an alternative.
  • Carotid ultrasound can be used to assess for carotid stenosis
    • Endarterectomy to remove plaques or carotid stenting to widen the lumen should be considered if there is carotid stenosis
43
Q

Briefly describe the secondary prevention of a stroke

A
  • Clopidogrel 75mg once daily (alternatively dipyridamole 200mg twice daily)
  • Atorvastatin 80mg should be started but not immediately
  • Carotid endarterectomy or stenting in patients with carotid artery disease
  • Treat modifiable risk factors such as hypertension and diabetes
44
Q

Who is involved in the MDT approach of caring for patients with a stroke?

A

It involves a multidisciplinary team including:

  • Nurses
  • Speech and language (SALT)
  • Dieticians
  • Physiotherapy
  • Occupational therapy
  • Social services
  • Optometry and ophthalmology
  • Psychology
  • Orthotics
45
Q

What are the complications of a stroke?

A
  • Depression
  • Deep vein thrombosis (DVT)
  • Aspiration pneumonia
  • Alteplase-related orolingual oedema
46
Q

What differentials should be considered for a stroke?

A
  • Transient ischaemic attack
  • Hypertensive encephalopathy
  • Hypoglycaemia
  • Complicated migraine
  • Seizure and postictal deficits
  • Brain tumour
  • Sepsis

Y4 Neurology and Special Senses: Neurology (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions