Strokes, Hemorrhage causes and types Flashcards Preview

Neurology - Anatomy and Physiology > Strokes, Hemorrhage causes and types > Flashcards

Flashcards in Strokes, Hemorrhage causes and types Deck (24):
1

What is cerebral perfusion driven by?

PCO2. PO2 only in severe hypoxia.

2

At what threshold of PO2 will cerebral blood flow increase?

Hypoxemia increases cerebral perfusion pressure when PO2 <50.

3

What is the relationship between cerebral perfusion pressure and PCO2?

Linear between 0 and 90 -- as PCO2 increases, cerebral blood flow increases.

4

What does therapeutic hyperventilation accomplish?

Blow off CO2, decrease PCO2, decrease cerebral blood flow; helps decrease intracranial pressure via vasoconstriction.

5

In what scenarios may therapeutic hyperventilation be useful?

Acute cerebral edema - stroke, trauma.

6

What is the formula for cerebral perfusion pressure?

CPP = MAP - ICP.
If MAP drops, or ICP too high, CPP drops. If CPP = 0, death.

7

Where is the most common site of saccular aneurysm?

Bifurcations in the circle of willis - most common site is junction of anterior communicating artery and anterior cerebral artery.

8

What can saccular aneurysm compress?

Optic chiasm -> bitemporal hemianopsia.

9

What does rupture of berry aneurysm cause?

Worst headache of my life!!

10

What diseases are berry aneurysms associated with?

APKD, Ehler-Danlos.

11

What is a charcot-bouchard microaneurysm?

Affects small vessels eg basal ganglia, thalamus. Associated with chronic HTN.

12

What causes pain in central-post stroke pain syndrome?

Neuropathic pain to due thalamic lesions. Initial paresthesias followed in weeks/months by allodynia. 10% of stroke patients.

13

What does the spinal tap for SAH look like?

xanthochromic - bloody or yellow.

14

What complication can occur 2-3 days after subarachnoid hemorrhage?

Risk of vasospasm due to blood breakdown. Treat w/ nimodipine. Risk of rebleed too.

15

How long does it take for irreversible damage to occur w/ hypoxia?

5 mins.

16

What are the most vulnerable areas of the brain to hypoxia?

HIPPOCAMPUS, neocortex, cerebellum, watershed areas.

17

How long until CT can detect changes?

6-24hr.

18

How long until diffusion weighted MRI can detect changes?

3-30mins.

19

What are the histologic features 12-48 hrs after stroke?

Red neurons.

20

What are the histologic features 24-72 hrs after stroke?

Necrosis and neutrophils.

21

What are the histologic features 3-5 days after stroke?

Macrophages - microglia.

22

What are the histologic features 1-2 weeks after stroke?

Reactive gliosis + vascular proliferation.

23

What are the histologic features >2 weeks after stroke?

Glial scar.

24

What is the threshold for tPA?

3-4.5 hrs of onset, no hemorrage/risk of hemorrhage.