NEURO 1: BRAIN INJURY & STROKE

Question 1

Name 4 mechanisms that cause acute brain injury

Answer 1

1. Ischemia & hypoxia
2. Excitotoxins
3. Reperfusion injury
4. Abnormal autoregulation of blood flow

Question 2

Why is the brain so sensitive to decreased perfusion?

Answer 2

Has low glycogen stores and low capacity for anaerobic metabolism

Question 3

How long does the brain need to be deprived of oxygen to cause irreversible damage?

Answer 3

5-10 minutes

Question 4

What is the main excitatory amino acid neurotransmitter that can cause excitotoxic effects?

Answer 4

Glutamate

Question 5

What are 2 reasons why there may be excess glutamate in the brain?

Answer 5

1. Cell membrane damage causing excess glutamate release
2. Lack of ATP being made causing impaired glutamate reuptake

Question 6

How does excess glutamate cause cell damage?

Answer 6

It binds to cell receptors that allow calcium and water entry into the cell causing cell swelling

Question 7

What are 4 ways reperfusion can cause further damage to brain tissue?

Answer 7

1. Reactive oxygen species
2. Invasion of immune cells causing inflammation
3. Compromised blood-brain barrier
4. Platelet aggregation

Question 8

If blood flow to the brain shows an impaired ability vasodilate (e.g. thrombosis, vasospasm, neutrophil aggregation), what is the end result?

Answer 8

Ischemia

Question 9

If blood flow to the brain shows an impaired ability to vasoconstrict (e.g. vascular injury), what is the end result?

Answer 9

Hyperperfusion and edema

Question 10

Which part of the Glasgow coma scale is the best predictor of patient outcomes following brain injury?

Answer 10

Motor response

Question 11

What is the term for an abnormal flexion response to pain?

Answer 11

Decorticate posturing

Question 12

What is the term for an abnormal extension response to pain?

Answer 12

Decerebrate posturing

Question 13

What is the term for an abnormal persistent rhythmic/jerky movement of the eyes?

Answer 13

Nystagmus

Question 14

What is the term for eyes not moving in the same direction?

Answer 14

Dysconjugate movement

Question 15

What is the term for paralysis of the eye muscles?

Answer 15

Ocular palsy

Question 16

What is the proper term for “doll eyes?”

Answer 16

Abnormal oculovestibular reflex

Question 17

What is the proper term for the blink response?

Answer 17

Corneal reflex

Question 18

What are 3 kinds of primary traumatic brain injury based on location?

Answer 18

1. Focal (coup)
2. Polar (coup-contrecoup)
3. Diffuse

Question 19

What are 3 kinds of primary TBI based on severity of injury?

Answer 19

1. Concussion (altered LOC but no damage)
2. Contusion (tissue damage present)
3. Intracranial hematoma (bleed)

Question 20

What are 3 types of intracranial hematoma based on compartment?

Answer 20

1. Epidural
2. Subdural
3. Subarachnoid

Question 21

What may cause an epidural hematoma?

Answer 21

Rupture of meningeal artery

Question 22

What is the typical presentation of an epidural hematoma?

Answer 22

1. Decreased LOC
2. “Lucid interval”
3. Rapid deterioration

Question 23

What may cause a subdural hematoma?

Answer 23

Damage to bridging veins

Question 24

How are the symptoms of subdural hematoma different from epidural hematoma?

Answer 24

May have a slower onset (e.g. subacute type shows symptoms 2-10 days later)

Question 25

Why may a subdural hematoma become chronic?

Answer 25

After healing, granulation tissue is more fragile

Question 26

What may cause a subarachnoid hematoma?

Answer 26

Rupture of cerebral aneurysm or AVM

Question 27

What causes symptoms of subarachnoid hematoma like meningeal irritation, hydrocephalus, and ischemia?

Answer 27

Blood spreads through CSF

Question 28

What does the acronym BEFAST stand for?

Answer 28

Balance (loss of balance, headache, dizziness) Eyes (blurred vision) Face (drooping) Arms (weakness, esp. one sided) Speech (difficulty) Time (call 911 immediately)

Question 29

What is the most common type of stroke?

Answer 29

Ischemic

Question 30

What are 2 risk factors for thrombotic stroke?

Answer 30

Atherosclerosis Coagulative disorders

Question 31

What are 2 risk factors for embolic stroke?

Answer 31

Cardiac dysfunction Cardiac dysrhythmia

Question 32

In stroke patients, what is the term for the region of cells in the brain surrounding an ischemic core that still receive partial blood flow and may still be viable?

Answer 32

Penumbra

Question 33

What is the term for a procedure to remove plaque from an artery to restore bloodflow?

Answer 33

Endarterectomy

Question 34

What is the term for a procedure to open up an artery using a ballon or stent?

Answer 34

Angioplasty

Question 35

Why should a transient ischemic attack be considered serious even if symptoms completely resolve?

Answer 35

About 1/3 of strokes are preceded by a TIA

Question 36

What are 2 kinds of hemorrhagic stroke?

Answer 36

1. Intracerebral hemorrhage (bleeding into brain parenchyma) 2. Subarachnoid hemorrhage (bleeding into subarachnoid space--between arachnoid and pia)

Question 37

What are 2 cardiac related risk factors for hemorrhagic stroke?

Answer 37

1. Hypertension 2. Use of anticoagulants

Question 38

What are 4 ways a hemorrhagic stroke damages the brain?

Answer 38

1. Compression injury to surrounding tissue 2. Cuts off blood supply causing ischemia 3. Direct toxic effects from bleed on brain tissue and vasculature 4. Inflammation

Question 39

How do the symptoms of hemorrhagic stroke differ from ischemic stroke?

Answer 39

The present in the same way, so imaging is required to determine the cause

Question 40

In what way is the pharmacological management of ischemic and hemorrhagic stroke different?

Answer 40

Ischemic stroke: trying to break up the clot by using thrombolytics and anticoagulants Hemorrhagic stroke: trying to encourage clotting to stop the bleeding by using reverse anticoagulants