Ellen - Path 2: Cns 2 Vascular/trauma

Front 1

What percentage of CO goes to the brain? What percentage of consumed oxygen?

Back 1

15% of the CO
20% of consumed oxygen

Front 2

What are the 3 major categories of CNS vascular disease?

Back 2

Generalized blood flow reduction (hypoxic-ischemic encephalopathy)
Infarcts from local obstruction (most common)
Hemorrhage

Front 3

Difference between hypoxia and ischemia? (usually occur together)

Back 3

Hypoxia is a decrease in available oxygen
Ischemia is a decrease in tissue perfusion (more serious than a pure hypoxia)

Front 4

What can cause a pure hypoxia? What are the symptoms of hypoxia (CNS sx)?

Back 4

Reduced atmospheric pressure
Decreased oxygen content
Symptoms: euphoria, drowsiness, apathy, poor judgment

Front 5

Are neurons tolerant to hypoxia or ischemia?

Back 5

Tolerance is low to ischemia (damage in 3-4 minutes) but they're fairly tolerant to hypoxia.

Front 6

How does the body maintain cerebral circulation?

Back 6

Autoregulation, maintaining constant flow via cerebrovascular resistance changes if BP > 50.
Anastamoses in the circle of willis

Front 7

What are the arterial border zones in the brain? Why are they important?

Back 7

Junctions of major arteries = the first to be deprived of blood during hypotension (ie superior cerebral convexity)

Front 8

Which parts of the brain are most succeptible to hypoxic ischemic encephalopathy? What does this look like microscopically?

Back 8

Hippocampal neurons and Purkinje cells.

Laminar necrosis (in grey matter)

Front 9

Major causes of hypoxic ischemic encephalopathy? What's the severity depend on?

Back 9

Arrhythmias, cardiac arrest, severe hypovolemia
Severity depends on pt age, duration of deprivation, preexisting disease

Front 10

What's the typical cause of cerebral infarcts? What are some other causes?

Back 10

Athrosclerosis of the internal carotid with thrombosis.
Can also be due to emboli, vasculitis, and trauma.

Front 11

What's the morphology of a cerebral infarct for the first 2 days?

Back 11

Death within minutes but the tissue looks normal for 4-12 hours then edema and hemorrhage + PMNs. 36-48 hrs = soft, dusky gross changes.

Front 12

What's an infarct look like after 72 hours?

Back 12

In 72 hrs macrophages appear. One month = extensive liquifaction. Several months = cavity formation

Front 13

What often precedes cerebral infarct?

Back 13

TIAs (often with middle cerebral and internal carotid arteries)

Front 14

What are the manifestations of a TIA?

Back 14

paresis, anesthesia, aphasia, visual field abnormalities, stupor. Frequently predictors of future, complete infarcts.

Front 15

What's a lacunar infarct?

Back 15

Small infarcts (less than 15 mm) deep in cerebrum - Affect the lenticular nucleus, thalamus, internal capsule, deep white matter, caudate nucleus, and pons

Front 16

Symptoms of a lacunar infarct?

Back 16

May be silent or cause deficit
May have pure sensory or motor deficit

Front 17

Name 4 types of intracranial hemorrhage.

Back 17

Infarction with bleeding
Spontaneous (usually htn)
Trauma (epidural or subdural)
Berry aneurysm (subarach)

Front 18

What are small aneurysms in the brain caused by hypertension called?

Back 18

Charcot-Bouchard microaneurysms

Front 19

How could you tell the difference between a hemorrhage and infarct?

Back 19

Hemorrhages don't follow a vascular distribution

Front 20

Where do spontaneous hemorrhages normally occur?

Back 20

Common in the basal ganglia

Front 21

Besides hypertension, what can cause a spontaneous intracranial hemorrhage? (5)

Back 21

bleeding diathesis, tumors, vascular malformations, cerebral amyloid angiopathy, and vasculitis

Front 22

Clinical signs of a spontaneous intracranial hemorrhage?

Back 22

Abrupt onset of local/global signs
Inc Intracranial Pressure
May = brain stem compression if mass effect is large enough.

Front 23

Clinical signs of hypertensive encephalopathy?

Back 23

headache
stupor
convulsions
retinal changes

Front 24

Morphology of hypertensive encephalopathy?

Back 24

cerebral edema, microinfarcts, petechiae, arteriolosclerosis

Front 25

Name the 4 morphologic types of vascular malformations.

Back 25

arteriovenous malformation
capillary telangiectases
venous angiomas
cavernous hemangioma

Front 26

Features of epidural hematoma?

Back 26

Arterial bleed, mostly middle meningeal. Frequently assoc with skull fracture. Fatal w/out tx due to brain stem compression.

Front 27

Features of subdural hematoma?

Back 27

Venous bleed due to tearing of the bridging veins (velocity changes/impact/shaking babies). Slow sx onset than epidural, may rebleed or become chronic.

Front 28

Gross morph difference between subdural and epidural?

Back 28

Subdural's create a cavity, epidural's more flat.

Front 29

What are contusions?

Back 29

Hemorrhages in superficial brain parenchyma due to blunt trauma - mostly at lobes where they contact bony prominences or dura

Front 30

What's a coup lesion? How does it differ from a contra coup?

Back 30

Coup = stationary head with moving object = injury where the impact occurs. Contra coup = injury opposite where impact occurs = moving head, stationary object

Front 31

What's a concussion?

Back 31

Transient loss of consciousness with no/minimal demonstrable injury (axonal nerve injury, maybe in the reticular activating system)

Front 32

Prognosis for a concussion?

Back 32

Complete recovery except for memory of the event

Front 33

Can you have edema and bleeding?

Back 33

Sure, why not!