Stroke

Question 1

What is NNT for thrombolysis? What effect does time have on this?

Answer 1

Very time dependent:
NNT is 4 if commenced within 90 minutes
NNT is 9 if between 90 minutes and 3 hours
NNT is 14 if 3-4.5 hours

Question 2

What is involved in the work up of a stroke?

Answer 2

• history, examination
• CTB, CT perfusion, CT angio
• US carotid (if angio not performed)
• MRI
• cardiovascular risk factors (lipids, HbA1c)
• ECG, holter, consider loop recorder
• ECHO
  Consider thrombophilia screen, vasculitis screen, Fabry’s disease screen

Question 3

Do those that get thrombectomy also get thrombolysed?

Answer 3

Yes, if they are a candidate and have no contraindications

Question 4

What are the contraindications to thrombolysis?

Answer 4

Haemorrhage on CT
Extensive hypodensity on CT (established infarct)
Active, non-compressible systemic bleeding
Recent GI or GU bleeding (3 weeks) or surgery/trauma (2 weeks)
BP>185/105 or BSL < 2.3
Unreversed anticoagulation (INR >1.7, or DOAC within last 48 hours)
Infective endocarditis, aortic dissection, malignant brain tumour

Question 5

What are the indications for thrombolysis?

Answer 5

Ischaemic stroke
Last well <4.5 hours ago
Potentially disabling deficit

Question 6

What are the indications for thrombectomy?

Answer 6

ICA or M1 lesion (or basilar artery)

0-6 hours of onset …or… 6-24 hours of onset with core volume <70mL

Question 7

Are small or large vessel thrombus associated with greater chance of recanalization with alteplase?

Answer 7

Small

Large (such as ICA or M1) are less likely to recanalize

Question 8

What are the features of alteplase related orolingual angioedema?

Answer 8

Usually contralateral to brain lesion
Occurs in 2% of cases or 5%  if taking ACEi
Occurs 15-100minutes post bolus
?Bradykinin related
Usually does not require hydrocortisone

Question 9

What are the major side effects of alteplase?

Answer 9

Bleeding

Orolingual angioedema

Question 10

What is the risk of a stroke within 7 days following an untreated TIA?

Answer 10

~10%

Question 11

How common is haemorrhagic transformation in large ischaemic strokes?

Answer 11

Almost universal

Question 12

What percentage of people with resolved symptoms within 24 hours (old definition of TIA), have diffusion lesion on MRI?

Answer 12

30%

Question 13

What is the rate of symptomatic ICH following thrombolysis?

Answer 13

1.7%

Question 14

What are risk factors for symptomatic ICH following thrombolysis?

Answer 14

delayed reperfusion, large core, severe hypoperfusion

Question 15

What is the major concern following thrombolysis?

Answer 15

symptomatic haemorrhagic transformation

Question 16

What is the NNT of stroke unit care to prevent 1x death/dependency?

Answer 16

28

Question 17

What is the definition of TIA? What is the pathophysiology?

Answer 17

Same pathophysiology as a stroke
Sudden onset of neurological symptoms, localisable to a vascular territory which resolves and in the absence of findings on MRI

Question 18

What are some common stroke mimics?

Answer 18

Migraine
Seizure with Todds paresis
Sepsis
Hypoglycaemia
Functional

Question 19

What is the average duration of a TIA?

Answer 19

10 minutes

Question 20

Where does stroke rank in causes of death worldwide?

Answer 20

Second

Question 21

What are the stroke subtypes?

Answer 21

Ischaemic (~85%)

Haemorrhagic (~15%)

Question 22

What structures on CTB are hyperdense in health?

Answer 22

Pineal gland, choroid plex