Neuroanesthesia Pt. 1 (Exam I) Flashcards
1
Q
List off the cranial nerves in order.
A
- Olfactory
- Optic
- Oculomotor
- Trochlear
- Trigeminal
- Abducens
- Facial
- Vestibulocochlear
- Glossopharyngeal
- Vagus
- Accessory
- Hypoglossal
2
Q
For Cranial Nerve I, what is the:
Nerve type?
Function?
A
Nerve Type: Sensory
Function: Smell
3
Q
For Cranial Nerve II, what is the:
Nerve type?
Function?
A
Nerve Type: Sensory
Function: Vision
4
Q
For Cranial Nerve III, what is the:
Nerve type?
Function?
A
Nerve Type: Motor
Function: Majority of Eye movement
5
Q
For Cranial Nerve IV, what is the:
Nerve type?
Function?
A
Nerve Type: Motor
Function: Eyeball Adduction
6
Q
For Cranial Nerve V, what is the:
Nerve type?
Function?
A
Nerve Type: Motor & Sensory
Function: Facial sensation & chewing
7
Q
For Cranial Nerve VI, what is the:
Nerve type?
Function?
A
Nerve Type: Motor
Function: Eyeball Abduction
8
Q
For Cranial Nerve VII, what is the:
Nerve type?
Function?
A
Nerve Type: Motor & Sensory
Function: Facial Expression & Taste
9
Q
For Cranial Nerve VIII, what is the:
Nerve type?
Function?
A
Nerve Type: Sensory
Function: Hearing & Balance
10
Q
For Cranial Nerve IX, what is the:
Nerve type?
Function?
A
Nerve Type: Motor & Sensory
Function: Taste & gag reflex
11
Q
For Cranial Nerve X, what is the:
Nerve type?
Function?
A
Nerve Type: Sensory & Motor
Function: Parasympathetic Innervation & gag reflex
12
Q
For Cranial Nerve XI, what is the:
Nerve type?
Function?
A
Nerve Type: Motor
Function: Shoulder Shrug
13
Q
For Cranial Nerve XII, what is the:
Nerve type?
Function?
A
Nerve Type: Motor
Function: Swallowing & Speech
14
Q
Which two cranial nerve share control over the gag reflex?
A
CN 9 & 10 (Glossopharyngeal & Vagus)
15
Q
Differentiate the functions of the temporal & parietal lobes of the brain.
A
- Temporal: Understanding language, memory, & hearing.
- Parietal: Speech & words, sense of touch, spatial perception.
16
Q
Which type of glial cell is only found in the PNS?
A
Schwann cells
17
Q
What are the types of glial cells?
A
- Astrocytes
- Oligodendrocytes
- Microglia
- Ependymal cells
- Schwann cells
All of these provide protection & support.
18
Q
Which glial cells regulate the blood brain barrier?
A
Astrocytes
19
Q
Which glial cells produced myelin?
A
- Oligodendrocytes (CNS)
- Schwann cells (PNS)
20
Q
Which glial cells are heavily involved in the immunofunction of the brain?
A
Microglia
21
Q
Which glial cells secrete CSF?
A
Ependymal cells
22
Q
Where is acetycholine seen as a neurotransmitter?
A
- PNS neuromuscular junctions
- CNS
- Most neurons of autonomic nervous system (preganglionic SNS & PSNS)
23
Q
What type of ACh receptors are located at the NMJ?
A
Nicotinic
24
Q
What type of ACh receptors are located in the PSNS?
A
Muscarinic
25
What type of ACh receptors are located in the CNS?
Muscarinic & Nicotinic
26
Which anitcholinesterase is used to treat myasthenia gravis?
Pyridostigmine
27
What acronym is used for cholinergic toxicity?
**S**alivation
**L**acrimation
**U**rination
**D**iaphoresis
**G**I Upset (diarrhea)
**E**mesis
28
What drugs are used to treat anticholinesterase toxicity?
- Atropine
- Pralidoxime
29
What drug class is used to treat Dementia, Alzheimer's, and Parkinson's disease?
How does this work?
Acetylcholinesterase Inhibitors (rivastigmine, donepizil, etc.)
↑ ACh availability in the CNS thus improving neuron to neuron communication.
30
What is the major excitatory neurotransmitter of the CNS?
Glutamate
31
Excessive activation of glutaminergic synapses leads to excessive influx of what ion?
What conditions does this present as?
- Ca⁺⁺
- Parkinson's, Huntington's, Alzheimer's
32
What amino acid is the precursor to dopamine?
Tyrosine
*Phenylalanine was mentioned in lecture but this is incorrect.*
33
Dopamine's effects in the CNS are generally _____ in nature.
inhibitory
34
Where are dopaminergic neurons located in the brain?
- Between substantia nigra & caudate nucleus/putamen
- In **Limbic system**, retinas, & olfactory system.
*Limbic = Reward system*.
35
Outside the CNS, dopamine exhibits paracrine effects. What does this mean?
Acts as a hormone on nearby cells.
36
What are the peripheral "paracrine" effects of dopamine?
- Inhibits NE release
- ↑ Na⁺ excretion
- ↓ insulin secretion
37
Degeneration of dopaminergic neurons occurs with _____ disease.
Parkinson's.
38
Why is carbidopa given in conjunction with levodopa for Parkinson's?
Prevents early conversion of levodopa to dopamine ensuring proper drug concentrations in the brain.
39
Why is levodopa given instead of dopamine for Parkinson's?
Dopamine cannot cross the BBB
40
Why should Reglan and Droperidol be avoided in patients with Parkinson's?
They antagonize dopamine
41
Which Dopamine antagonists are utilized for N/V?
- Droperidol
- Metoclopramide
42
Where is epinephrine utilized as a neurotransmitter in the CNS?
- Medulla Oblongata
- Pons
43
Where is norepinephrine utilized as a NT in the CNS?
- Locus Coeruleus
44
Where are norepinephrine and epinephrine used as NT's in the PNS?
- SNS Ganglia
- Postganglionic SNS neurons
45
What is serotonin synthesized from?
Tryptophan
46
Where is most of the body's serotonin produced?
GI Tract by enterochromaffin cells
47
Where is serotonin located in the brain?
Pons & medulla
48
Where is serotonin stored? (In regards to hematology)
- Stored in platelets
*Released during clot formation (promotes wound healing)*
49
What does serotonin do to blood vessels in a pathologic state?
Vasoconstricts
(HTN, atherosclerosis)
50
What does serotonin do to blood vessels in a physiologic state?
Vasodilates (via NO release)
51
What NT, released by the gut, causes nausea?
Serotonin
52
What type of drugs are paroxetine and sertraline?
SSRI's
53
What type of drug is venlafaxine?
SNRI
54
Which serotonin antagonist is used to treat N/V?
Ondansetron
55
Besides the CNS, what organ system has large amounts of GABA?
Why is this?
- Pancreas
- GABA inhibits glucagon secretion
56
What arteries provide blood flow to the entirety of the brain?
- 2 Common Carotid Arteries
- 2 Vertebral Arteries
57
The internal carotid artery bifurcates to become the....
Anterior & Middle Cerebral Arteries
(ACA & MCA)
58
The vertebral arteries join to form the ______ artery, which then divides into the ______ _______ arteries.
Basilar
Posterior Cerebral
59
What vessels merge to form the circle of Willis?
- ACA's
- MCA's
- PCA's
60
What is the order of perfusing arteries that occurs after the Circle of Willis?
Superficial to deep
1. Pial Arteries (cover surface of brain)
2. Penetrating Arteries
3. Intracerebral arterioles
4. Capillaries
61
Is the circle of willis a high or low resistance vascular formation?
Low Resistance
62
How many anterior communicating arteries of the Circle of Willis are there?
1
63
How many Posterior communicating arteries of the Circle of Willis are there?
2
64
Circle of Willis Picture
65
What anatomic structure is located at the blue area in the picture below?
Locus Coeruleus
66
What structure is indicated by 1 in the figure below?
Anterior Cerebral Artery
67
What structure is indicated by 2 in the figure below?
Anterior Communicating Artery (ACOM)
68
What structure is indicated by 3 in the figure below?
Middle Cerebral Artery
69
What structure is indicated by 4 in the figure below?
Posterior Communicating Artery (PCOM)
70
What structure is indicated by 5 in the figure below?
Posterior Cerebral Artery
71
What structure is indicated by 6 in the figure below?
Basilar Artery
72
What structure is indicated by 7 in the figure below?
Vertebral Artery
73
What structure is indicated by 8 in the figure below?
Internal Carotid Artery
74
What is the most prominent venous sinus of the superficial venous system of the brain?
Superior Sagittal Sinus
75
What are the vascular structures of the superficial venous system of the brain?
- Superior Sagittal Sinus
- Transverse Sinus
- Cavernous Sinus
76
What are the vascular structures of the deep venous system of the brain?
- Great Cerebral Vein
- Inferior Sagittal Sinus
- Straight Sinus
77
Where do the superficial and deep venous systems of the brain meet?
Confluence of Sinuses (They then drain out into the Internal Jugular Vein)
78
Internal jugular vein drainage is always symmetric between both veins. T/F?
False
79
The brain is 2% of the body's total weight but consumes _____% of CO.
15 - 20%
80
The average weight of a human brain is ______ grams.
~ 1400 grams
81
What is the average cerebral blood flow of a human adult?
50 mL / 100g of brain tissue / min
82
Where does the brain store glucose?
It does not!
(Cerebral glucose requirement is very important).
83
At what cerebral blood flow would be expect to see impairment and EEG slowing?
< 20 - 30 mL / 100g / min
84
At what cerebral blood flow would be expect to see an isoelectric EEG?
15 - 20 mL / 100g / min
85
At what cerebral blood flow would be expect to see irreversible brain damage?
≤ 10 mL / 100g / min
86
CPP = ?
CPP = MAP - ICP
87
What are the 3 subsets of cerebral autoregulation?
- Myogenic
- Neurogenic
- Metabolic
88
What is the cerebral autoregulation MAP window?
~ 60 - 140 mmHg
89
What occurs to the cerebral autoregulation curve in a patient with chronic hypertension?
The curve shifts to the right
90
Cerebral arterioles ___ when CPP is down.
Dilate
91
Cerebral arterioles ______ when CPP is high.
Constrict
92
Local Dilation/Constriction of cerebral arterioles is the _____ facet of cerebral autoregulation.
myogenic
93
What is the neurogenic aspect of cerebral autoregulation?
SNS innervation of large cerebral arteries and the release of vasoactive neurotransmitters.
94
Between MAP, myogenic control, metabolic requirements, and neurogenic control, which of these is the weakest factor in cerebral autoregulation?
Neurogenic
95
What are the four factors that make up the metabolic facet of cerebral autoregulation?
- pH (CO₂ & H⁺)
- O₂ concentration
- CMRO₂
- Astrocytes
96
What is the CMRO₂ of the brain in a resting state?
3mL of O₂ / 100g / min
97
What is the CMRO₂ of a 1500g brain at a resting state?
3 mL O₂ x 15 = **45 mL O₂ per min**
98
Systemic hypoxia causes cerebral vaso_______.
vasodilation
99
What is the term for cerebral blood flow matching CMRO₂?
Neurovascular coupling
100
For each 1°C drop in temperature, CMRO₂ decreases by _____.
6 - 7 %
101
Hyperthermia will increase CMRO₂ up until ___°C, then CMRO₂ decreases due to metabolic dysfunction.
42°C
102
Severe hypoglycemia will have what effect on CBF? What about CMRO₂?
↓BG = ↑CBF
↑CBF = ↑CMRO₂
*Brain will try to compensate for low BG by increasing CBF thus ↑CMRO₂*.
103
Severe hypoglycemia occurs at less than ____ mg/dL.
36
104
What is the mechanism for increased CO₂ resulting in cerebral vasodilation?
↑CO₂ combines with H₂O in blood.
↓
Carbonic acid (H₂CO₃) forms
↓
H₂CO₃ dissociates into H⁺ & HCO₃⁻
↓
H⁺ & HCO₃⁻ cause vasodilation
105
CBF is ________ proportional to PaCO₂.
Directly
106
What are the primary functions of astrocytes?
- Provide support & nutrition to neurons
- Regulate neuroinflammation
- Antioxidant responses
107
What is the mechanism for astrocyte mediated vasodilation?
- Glutaminergic neurons stimulate astrocytes
↓
Astrocyte has ↑ CO₂
↓
Astrocyte releases NO
↓
local vasodilation
108
What effect will N₂O have on cerebral blood flow?
N₂O = minor ↑CBF
N₂O + VAA = More ↑CBF
109
Ketamine is a potent cerebral _________.
vasodilator
110
What is the Robinhood effect?
*Reverse Steal Effect*
↓ cerebrovascular response to CO₂ resulting in:
- Healthy brain tissue is vasoconstricted
- Ischemic areas get vasodilated (and thus more blood flow).
111
What drug class exhibits the Robinhood Effect?
Barbiturates
112
Differentiate the Robinhood Effect & Circulatory Steal?
- Robinhood = vasoconstricted healthy areas and vasodilated (more CBF) to ischemic areas.
- Circulatory Steal = Vasodilation everywhere
113
Which artery is indicated by 7 in the figure below?
Anterior Spinal Artery
114
Which artery is indicated by the star in the figure below?
Artery of Adamkiewicz
115
Which artery is indicated by 6 in the figure below?
Posterior Spinal Arteries (2)
116
The anterior spinal artery runs from the ______ cephalically to the _______ caudally.
Foramen magnum to the filum terminale
117
Where does the anterior spinal artery originate from?
The vertebral artery
118
What artery supplies the anterior ⅔ of the spinal cord?
Anterior spinal artery
119
What artery supplies the posterior ⅓ of the spinal cord?
Posterior Spinal Arteries
120
What arteries feed the posterior spinal arteries?
Radicular & medullary arteries at each spinal level
121
The Artery of Adamkiewicz is the largest what?
Largest anterior medullary segmental artery
122
Spinal segmental arteries branch off of the _____.
aorta
123
The Artery of Adamkiewicz most commonly originates from where?
Left side of the aorta around the T9 - T12 levels.
124
What is the significance of the Artery of Adamkiewicz?
Provides major blood supply to the anterior thoracolumbar spinal cord.
125
What usually remains intact if the Artery of Adamkiewicz is damaged?
Sensory functions of the spinal cord.
*Motor typically damaged*.
126
What is Tethered Cord Syndrome?
Syndrome where spinal cord is attached to spinal column and stretching may cause injury.
127
What structure is indicated by 1 below?
Anterior Communicating Artery
128
What structure is indicated by 2 below?
Internal Carotid Artery (Left)
129
What structure is indicated by 3 below? What large artery precedes this one?
* Middle Cerebral Artery
* Internal Carotid Artery
130
What structures are indicated by 4 below?
Posterior Communicating Arteries
131
What structure is indicated by 7 below?
Superior Cerebellar Artery
132
What structure is indicated by 8 below? On which structure does this artery sit? What two arteries converge to form this one?
* Basilar Artery
* Pons
* Left and Right Vertebral Arteries
133
What structure is indicated by 11 below? What is the importance of this structure? Where does this structure sit?
* The Right Vertebral Artery
* This structure perfuses the posterior of the brain
* The two vertebral arteries sit on the brainstem
134
What structure is indicated by 12 below?
PosteroInferior Cerebellar Artery
135
What structure is indicated by 13 below?
AnteroInferior Cerebellar Artery
136
What structure is indicated by 15 below?
Precommunicating (P1) of the Posterior Cerebral Artery
137
What structure is indicated by 16 below?
Postcommunicating (P2) of the Posterior Cerebral Artery
138
What structure is indicated by 17 below?
Precommunicating (A1) of the Anterior Cerebral Artery
139
What structure is indicated by 18 below?
Postcommunicating (A2) of the Anterior Cerebral Artery
140
What structure is indicated by 19 below? What makes up this artery? Where does its blood flow come from?
* Anterior Cerebral Artery
* A1 and A2
* Middle Cerebral Artery
141
What structure is indicated by 1 below?
Superior Cerebellar Artery
142
What structure is indicated by 2 below?
Basilar Artery
