Stroke + TIA Flashcards
1
Q
What are generalised causes of interrupted O2 supply
A
Low O2 in blood
Inability to use O2
Inadequate supply of blood
2
Q
What causes low O2 in blood
A
CO poisoning
Drowning
Respiratory arrest
3
Q
What causes Inability to use O2
A
Cyanide poisoning
4
Q
What causes inadequate blood supply
A
MI
Hypotension
5
Q
What causes a zonal / watershed patter of infarction
A
Hypotension
Central arteries will be perfused
Other areas poorly perfused
6
Q
What causes cortical necrosis
A
MI
7
Q
What causes localised / focal interruption to 02 supply
A
Atheroma
Thromboembolism
Ruptured aneursym
Arterial dissection / venous sinus thrombosis = rare
8
Q
What is a stroke
A
Focal neuro deficit of sudden onset due to disruption of blood supply to the brain
>24 hours
Causes infarction as brain = aerobic metabolism
9
Q
What are two types of stroke
A
Ischaemic (85%)
Haemorrhagic
- ICH = most common
- SAH can cause 5%
10
Q
ANATOMY OF CIRCULATION
A
ICA Gives of Retinal Then ACA then MCA MCA most affected atherosclerosis Retinal if embolic 2 vertebral arteries (posterior brain) Give of basilar and cerebellar
11
Q
What causes ischaemic stroke
A
Large atherothromboembolism or small vessel
Cardioembolic - AF / IE / MI
Rare Carotid dissection / trauma Venous sinus thrombosis Hypercoagulable state Sickle cell
12
Q
What causes haemorrhage stroke
A
HYPERRTENSION Ruptured aneurysm Vessel spasm AV malformation Tumour Anti-coagulation / thrombolysis
13
Q
What are causes of stroke in the young
A
Carotid artery dissection = always consider Vasculitis SAH Venous sinus thrombosis Anti-phospholipid syndrome
14
Q
DDX of stroke
A
Head injury Severe migraine Hypo or hyperglycaemia - always exclude Metabolic - hyponatraemia Facial nerve palsy Subdural Tumour Weirnecke's encephalopathy Hepatic encephalopathy Encephalitis Abscess Drug overdose Vestibular disorder Transient global amnesia Demyelination Neuropathy Functional Sx
15
Q
What are RF for ischaemic stroke
A
Age Male Hypertension = most important modifiable RF Previous stroke or TIA Smoking High cholesterol DM Hypercoagulable Vasculitis OCP FH Alcohol Obesity Poor cardiac / established CVD disease AF for cardioembolic
16
Q
What are RF for haemorrhagic stroke
A
Age Hypertension AV malformation Anti-coagulant Thrombolysis
17
Q
Atheroma RF
A
High BP
High cholesterol
Smoking
DM
18
Q
What causes thrombosis
A
Change in vessel wall
Change in blood constituents
Stasis of blood flow
19
Q
RF for AF
A
P - pulmonary disease / pheochromocytoma I - IHD R - rheumatic fever / MS / MR A - anaemia / age T - thyrotoxicosis E - elevated BP / ethanol S - sepsis / sleep apnoea
20
Q
When are signs of stroke worse
A
At onset
Then begin to improve
21
Q
What investigations do you do in all patients presenting with stroke to ED
A
Vitals inc BP (often high)
Neuro exam
Bloods
ECG
CXR
Non-contrast CT = 1st line imaging to exclude haemorrhage ASAP
MRI = better at showing infant (but not in 1st stages)
22
Q
What bloods
A
FBC, U+E, LFT, lipids, glucose, ESR, coagulation
Preg test, LFT and toxicology in selected patient
23
Q
Why do you do ECG
A
Look for AF / ischaemic changes
If AF - may want to do ECHO
24
Q
Why do you do imaging and when
A
EXLUDE BLEED To see if suitable for thrombolysis CT if - Thrombolysis indicated - On anti-coagulant - Bleeding tendency - GCS <13 - Unexplained progressive / fluctuating symptoms - Papilloedema / stiff neck / fever - Severe headache at onset
25
What is FAST
```
Face
Arms / legs - loss of power./ sensation
Speech - lost / disturbed
Loss of vision
Loss of coordination / balance
```
26
What are common visual problems in stroke
Hemianopia or diplopia
If whole eye affected tends to be retinal problem
Vertical nystagmus if cerebellar
27
What score is used for assessment
ROSIER
28
What must you do before ROSIER
Exclude hypoglycaemia
29
What does ROSIER Include
- ve 1
- LOC
- Seizure at onset
- Syncope
+1
- Asymmetric arm weakness
- Asymmetric leg weakness
- Speech disturbance
- Visual field defect
30
When is a stroke likely
If >0
31
What do you do if patient presents 6 weeks after event
```
Carotid doppler of both carotids
Put on secondary prevention
Endarectomy if >70% stenosis
If 100% then no chance of emboli
Can do CTA or MRA to look for aneurysm
```
32
What are the guidelines for TIA / non-disabling stroke
BMT
| Carotid imaging within 1 week
33
If not significant stenosis
Continue BMT
34
If significant >70% + symptomatic (TIA / stroke / amuorosis fujax)
Refer for endarectomy
If no operation 1 in 5 = stroke
1 in 100 chance if operation
35
What other tests can be done after stroke to look for cause
```
Carotid dopper = 1st line
CXR
24 hour ECG to look for AF
ECHO
Hyper-coagulable blood screen
Cerebral angiogram
```
36
What is the immediate Rx of stroke
ABCDE management
- Dehydration common and should be treated with bolus
- Avoid overload as will exacerbate cerebral oedema
Immediate CT to exclude haemorrhage
Aspirin 300mg once haemorrhagic excluded with CT (withhold if getting thrombosis)
Continue anti-platelet
Maintain BP, fluid, O2 and temp
Only treat BP if hypertensive emergency as may impair perfusion e.g. encephalopathy, MI or dissection, PET or thrombolysis - want <185 as may impair perfusion or haemorrhage with BP >200
Protect airway as risk of hypoxia + aspiration
Avoid hyperglycaemia as poor prognosis
Screen swallow - NBM till assessed
Involve stroke team = very important
37
What is 1st line in ischaemic stroke
Thromboylsis + Thrombectomy If within 4.5 hours
38
When do you do thrombosis
If admitted within 4.5 hours of ischaemic stroke
Must do CT first to exclude haemorrhage
If >4.5 = stroke team as tissue dead
39
What is 1st line thrombosis agent
Alteplase (tisse plasminogen activator which breaks down plasminogen to plasmin which breaks down clot)
40
What do you do post thromboylsis
CT to look for bleed
41
When can you offer thrombectomy
If within 6 hours
Confirmed anterior circulation stroke by CTA or MRA
Possibly if posterior
Can extend 6-24 hours if imaging shows can salvage tissue
42
What are absolute CI to thrombolysis
```
Symptoms improving
Symptoms >4.5 hours
Haemorrhage on brain imaging
Previous ICH
Seizure at onset
Intracranial neoplasm
Minor neuro deficit or rapid improvement e.g TIA
Prior stroke or traumatic brain injury within 3 months
Symptoms suggesting SAH even if CT normal
LP within 7 days
Active bleeding
Varices
GI haemorrhage within 3 week
Pregnancy
Uncontrolled BP >185
Platelet <100
INR >
Blood glucose <50 or >400
```
43
What are relative CI
```
Patient on anti-coagulant - Warfarin / heparin
Bleeding disorder
Low platelet
Low or high BG
<16 or >80
```
44
What is given as secondary prevention after stroke
```
Aspirin 300mg for 2 weeks
Then start anti-platlet
Carotid endarectomy >70% stenosis
Anti-hypertensive
Statin if cholesterol
```
45
What is 1st line anti-platelet
Clopidogrel (ADP antagonist)
46
What is given if clopidogrel CI
Aspirin (thoromboxane A2 inhibitor) high dose +
| Dipyramidole inhibitor
47
What do you do if AF post stroke
DO NOT restart anti-coagulation until CT excluded haemorrhagic and 14+ days since ischaemic
Warfarin or DOAC
48
Do you go on anti-platelet if on anti-coagulant
No
| Only if needed for other co-morbid
49
What do you do for haemorrhagic stroke
Neurosurgeon
Craniotomy to give space
Stop and reverse anti-coagulant
Lower BP
50
What is the Oxford classification of stroke
```
Assess for initial signs of
Unilateral hemiparesis
Unilateral sensory loss
Of face / arm or leg
Homonymous hemianopia
Higher cognitive dysfunction e.g. dysphasia
```
51
What are the types of stroke
TACS - total anterior
PACS - partial anterior
LACS - lacunar
POCS - posterior
52
What artery affected in TACS
MCA and ACA
53
What part of criteria fulfilled
```
ALL 4
Motor loss in 2 / 3
Sensory loss
Must have hemianopia
+ cognition - dysphagia / neglect
NO BRAIN STEM
```
54
What artery affects in PACS
Smaller arteries of anterior circulation / MCA
55
What part of criteria filled
```
At least 2+
Motor loss
Sensory loss
One of hemianopia or cognition - dysphasia / neglect
No brain stem
```
56
What artery affected in lacunar
Arteries around basal ganglia / thalamus
57
What criteria fulfilled
1+ of
Motor / sensory loss
Can be pure sensory
Ataxia hemiparesis
NO hemianopia / dysphasia / neglect or brains stem
58
What arteries in posterior stroke
Vertebrobasillar
59
What part of criteria filled
1+ of cerebellar or brain stem Sx
Motor loss
Sensory loss
Hemianopia +- dysphasia + -neglect
60
What is a TIA
Ischaemic stroke <24 hours
New definition = tissue based
Due to reversible ischaemia so not permanent
NO INFARCTION
61
What causes TIA
Main causes
Atherothrombembolism
Cardiombolism post MI / AF
```
Other
Dissection
Hyperviscosity e.g. polycytheaemia / myeloma
Sickle cell
Vasculitis
```
62
What is the DDx
Hypoglycaemia
Migraine + aura
Focal epilepsy
Retinal bleed
63
What does crescendo TIA suggest
Critical stenosis of artery
64
What do you do if suspected TIA
```
Neuro exam
Vital signs
FBC, ESR, U+E, glucose, lipids
Imaging to exclude haemorrhage
- MRI better for TIA - images posterior better and acute ischaemia
```
65
What do you do for cause
CXR
ECG
ECHO
Hyper-coagulbale screen
66
What are the guidelines TIA / non-disabling stroke
Same
67
What do you do if suspected TIA
Aspirin 300mg unless CI
- Anti-coagulant
- Bleeding disorder
- Already on aspirin 75mg - continue until review
Risk of stroke = highest first 48 Horus
Admit for CT and to exclude haemorrhage if on anti-coagulant
Stroke specialist within 24 hours
68
If TIA suspected within last 7 days
Urgent assessment within 24 hours
| Give aspirin 300mg if symptoms fully resolved
69
If >7
Still refer within 7 days
70
If 1+ or severe stenosis
Discuss need for admission with specialist as crescendo
71
What do you post
Control CVS RF - BP / cholesterol / DM / smoking
Same as stroke
Aspirin 300mg 2 weeks - If already on non benefit
Clopidogrel 75mg
Control BP
Anti-coagulant if suspect AF
Perform ABCD2 score
72
What does TIA suggest
Increased risk of stroke
73
What is important to remember for stroke
```
Rapid onset
Depends on part of brain affected
Abnormal movement unusual
+ve visual Sx more likely to be migraine
Severe headache is unusual
```
74
If a stroke in <55 what investigations for cause
Thrombophilia and autoimmune screen
MRI outpatient
Holter for AF
75
What score is used in TIA to estimate risk of stroke
```
ABCD2
Age >60
BP >140/90
Clinical features
Duration
DM
```
If score >4 = aspirin 300mg + specialist within 24 Horus
76
What do you give with Aspirin
PPI if indicated
77
How may carotid stenosis present
Carotid bruit
1st line = doppler USS in all patients with TIA
If >70% stenosis = endarectomy within 7 days unilateral unless both >70%
78
What is a penumbra
Area around infarcted tissue which is hypo-perfused
| May be saved if reperfused
79
Common cause of stroke in the young
Carotid artery dissection
80
What is known precipitating factor
Head or neck trauma
| Aneurysm / HTN and atherosclerosis also indicated but consider dissection if no known CVS RF
81
How does it present
Ipsilateral headache
Face or neck pain
Horner's
25% can have neck pain alone - sudden severe and persistent
82
How do you Dx
CTA OR MRA
83
How do you Rx
Usually resolves
84
If posterior bleed noticed on CT what is needed
Neurosurgery
85
Why can posterior strokes be difficult to Dx
Similar to benign
BPPV
Labrynthitis
86
What are important symptoms to distinguish
Vertical nystagmus
Vomiting
Diplopia
87
Who always gets a CT gif TIA
If on anti-coagulant to exclude haemorrhage
