Exam 1: A&P, hemodynamics, fluids, anesthesia agents Flashcards
1
Q
what part of the neuron contains the nucleus
A
cell body
2
Q
what part of the neuron receives signals
A
dendrites located on cell body
3
Q
what part of the neuron carries the action potential from the cell body to the axon terminals
A
axon
4
Q
what part of the neuron transmits signals to other cells
A
axon terminal
5
Q
what part of the neuron covers the axon and speed transmission
A
myelin sheath (made of fat)
6
Q
what part of the neuron makes the myelin
A
schwann cells
7
Q
what is the space between schwann cells where electrical messages jump
A
Nodes of Ranvier
8
Q
nueron cell body in the CNS is made of _________ matter
A
grey
9
Q
myelinated axons are ________ matter
A
white
10
Q
what are the types of neuronal cells
A
motor, sensory, interneurons
11
Q
motor nerves are _________polar
A
multi
12
Q
sensory nerves are _______________polar
A
pseudomonipolar
13
Q
internuerons are ___________polar
A
pseudomonipolar
14
Q
what are the 4 types of neuroglial cells
A
astrocytes
oligodendrocytes
microglial
ependymal
15
Q
what do neuroglial cells lack
A
dendrites, axonal processes
16
Q
what neuro cell is essential for BBB, structural support, injury repair, are what most neoplasma aris from, have pair neurons and nerve terminals
A
atrocytes
17
Q
what neuro cell forms myelin sheath of axon in brain (regeneration)
A
oligodendrocyte
18
Q
what neuro cell is th smallest cell, acts like a macrophage for debris, and is transported to sites of neuro injury
A
microglial
19
Q
what parts of brain lack a BBB
A
postrema
pituitary gland
pineal gland
choroid plexus
portions of hypothalmus
20
Q
what neuro cell lines the roof of the 3rd and 4th ventricles and central spinial canal, they form the choroid plexus
A
ependymal
21
Q
what is the thickest and most outer layer of the spinal cord
A
dura mater
22
Q
what seperates the cerebral hemispheres
A
falx cerebri
23
Q
what seperates the occipital and cerebellum
A
tentorium cerebelli
24
Q
what layer of the spinal cord is avascular and is joined to the dura mater
A
arachnoid mater
25
what layer of the spinal cord is adhered to the brain and spinal cord
pia mater
26
what is the space between pia and arachnoid mater filled with CSF
subarachnoid space
27
how far down does the subarachnoid space extend to
s2-s3
28
what space surrounds the dura in spinal canal, contains venous plexus
epidural space
29
what are some safety mechanisms in the brain
BBB
CSF
30
what is function of BBB
isolates brain to maintain homeostasis, tight barrier for water soluble molecules
31
what is the volume of CSF
150 ccs
32
what is function of CSF
cushions the brain provides an extracellular milieu for neurons and glial cells
33
what lobe of brain is for judgement, foresight, voluntary movement and smell
frontal
34
what lobe of brain is for intellect, emotion, and hearing
temporal
35
what area of the temporal lobe controls speech
Brocas
36
what area of temporal lobe conrols speech comprehension
Wernickes
37
what lobe of the brain controls visual stimuli
occipital lobe
38
what part of the brain controls swallowing, breathing, and heartbeat
brainstem
39
what part of the brain controls movement
the motor cortex of the frontal lobe, forward of the central sulcus
40
what part of the brain controls pain sensation
sensory cortex, posterior of central sulcus
41
what part of the brain controls coordination
cerebellum
42
what lobe of the brain controls comprehension of language
parietal lobe
43
what part of brain is the master neurohumerol organ and regulates body function
hypothalmus
44
what part of brain regulates emotion/pain response, appetite and stress response
amygdala
45
what part of brain does movement and reward
basal ganglia
46
what part of brain is the sensory gateway
thalamus
47
what part of brain regulates memmory
hippocampus
48
list spinal/epidural layers
Skin,
sub q tissue,
supraspinous ligament,
interspinous ligament,
ligamentum flavum,
epidural space,
dura mater,
arachnoid mater,
sub arachnoid space,
pia mater,
spinal cord
49
where is CSF made
choroid plexus of lateral third and fourth ventricles in subarachnoid space
in ependymal cells lining the ventricles
50
what is total volume of CSF
150 mls
51
what is rate of CSF production
30ccs/hr
52
what is pressure of CSF
5-15 mmHg
53
where is CSF absorbed
arachnoid villi into the venous system
54
what is Specific Gravity of CSF
1.002-1.009
55
what is the pH of CSF
7.32
56
what are the components of CSF
K, Ca, HCO3, Glucose (plasma)
57
what is the flow of CSF
Lateral ventricles -
interventricular foramen (foramen of Monro)
third ventricle
cerebral aqueduct
fourth ventricle
lateral apertures and median aperture
subarachnoid space-
arachnoid villi
superior sagittal sinus
58
how often is CSF volume replaced
every 3-4 hours
59
what kind of nerves originate on the dorsal spinal cord
sensory/afferent
60
what kind of nerves originate on the ventral spinal cord
motor/efferent
61
describe pathway of stimulus to response
peripheral receptor receives stimuli
sensory neruon (afferent) carries mease to CNS
interneuron
motor neuron (efferent) message from CNS to body
effector- muscle or gland carries out response
62
what arteries feed the circle of willis
internal carotid (anterior)
vertebral arteris (posterior)
63
what arteries branch off of the circle of willis
anterior, middle, and posterior arteris
64
what is cranial nerve 1
olfactory (smell)
65
what is cranial nerve 2
Optic - vision
66
what is cranial nerve 3
Oculomotor.
Functions in raising the eyelid, directing the eyeball, constricting the iris, and controlling lens shape.
adduction of the eye medial
67
what is cranial nerve 4
Trochlear. Primarily a motor nerve that directs the eyeball. (superior oblique)
68
what is cranial nerve 5
Trigeminal. Three divisions: Opthalmic (V1), Maxillary (V2), and Mandibular (V3).
mastication, sensory from face
69
what is cranial nerve 6
Abducens- abduction of the eye (lateral)
70
what is cranial nerve 7
Facial- muscle of face, taste (anterior 2/3 tongue)
71
what is cranial nerve 8
Vestibulocochlear/acoustic
balance-vestibular
audition- cochlear
72
what is cranial nerve 9
Glossopharyngeal taste (posterior 1/3 tongue) carotid body and sinus efferent
73
what is cranial nerve 10
Vagus, heart, motor control fo larynx and pharynx
74
what is cranial nerve 11
accessory, shoulder and head movement
75
what is cranial nerve 12
Hypoglossal moves tongue
76
which cranial nerves are sensory
1
2
8
77
what cranial nerves are motor
3
4
6
11
12
78
what cranial nerves are mixed
5
7
9
10
79
how do alzheimers drugs like rivastigmine (exelon) work
acetylcholinesterase inhibitor
blocks breakdown of acetylcholine to increase levels in brain and provide better transmission
80
what kind of neurotransmitter/receptor do interneurons use
ACH and nicotinic receptor
81
what kind of neurotransmitter/receptor do parasympathetics use
ACH and muscarinic at target organ
82
what kind of neurotransmitter/receptor do sympathetics use
NE or ACH and muscarinic receptor
83
what kind of neurotransmitter/receptor does somatic system use
ACH and nicotinic
84
what percent of total body oxygen does brain use
20%
85
the brain uses 60% of O2 to make __________ and support electrical activity
ATP
86
what is CMRO2 in adults
3-3.8 ml/100g/min or 50 ml/min
87
the brain reaches unconsciousness after ______________ of interrupted blood flow
10 seconds
88
after __________________ of no blood flow the brain has cellular injury
3-8 min
89
what is volatile effect on brain (CMR, CBF, ICP)
decrease CMR
increase CBF
increase ICP
90
what is the best volatile for neuro and why
ISO
increases CSF absorption
91
What is CPP and how is it calculated
cerebral perfusion pressure
CPP = MAP - ICP
92
what is normal CPP
80-100 mmHg
93
what happens with CPP <50
slowed EEG
94
what happens with CPP <25
irreversible brain damage
95
what range of MAP is CBF stable
60-160 mmHg
96
CBF directly mirrors ___________
PaCO2
97
how does a lower hct effect blood flow
improved
98
how does a high hct effect blood flow
decreased BF
99
what does hypoglycemia do to brain
injures
100
what does hyperglycemia do to brain
exacerbates global and focal hypoxic brain injury by accelerating cerebral acidosis and cellular injury
101
what rate does brain consume glucose
5mg/100g/min
102
MAP calculation
(SBP+ 2x DBP )/3
103
what does a decrease in CPP lead to
cerebral vasodilation
104
what does an increase in CPP lead to
cerebral vasoconstriction
105
what is the result of crazy HTN
disruption in BBB, brain swelling and bleeding
106
what is result of hyperventilation on brain
CO2 decreases, vessels vasoconstrict, decreased blood flow, inverse steal causing ischemia
107
what ICP level leads to brain herniation
>30 mmHg
108
what are s/s increased ICP
HA, vomiting, papilledema, vision changes, change in mentation/somnolence, GCS reduction
109
what is physiology of increased ICP
-Displacement of CSF from cranium to the spinal canal
-Increase in CSF absorption
-Decrease in CSF production
-Decrease in total cerebral blood volume
110
what is optimum HCT for neuro patients
30-34% for optimal carrying capacity
111
what is optimum PaO2 and SpO2 for neuro patients
normal
112
what is optimum CO2 for neuro patients
normal (35-45) or higher
113
GCS
EYE
4- spontaneous
3 sound
2 pressure
1 none
Verbal
5 oriented
4 confused
3 words
2 sounds
1 none
MOTOR
6 commands
5 localizes
4 normal flexion
3 abnormal flexion
2 extension
1 none
114
what is GCS score 13-15
mild
115
what is GCS score of 9-12
moderate
116
what is GCS score of 3-8
severe
117
what does the BP tell us in the brain...
no idea but maintain or slightly increase BP during anesthesia
118
what happens to CBF when PaO2 is 50mmHg or less
increases CBF
119
CBF changes ________________ per mmHg change in CO2
1-2 ml/100g/min
120
CBF changes __________ per every 1* change in celsius
5-7%
121
what is cushings triad
HTN, bradycardia, irregular breathing
122
what does cushing triad tell us
herniation/increased ICP
123
what kind of fluids do we avoid in intracranial HTN
glucose containing fluids
124
where do you zero a line for intracranial HTN
circle of willis
125
what paralyzer do we avoid in intracranial HTN
succs
126
what safety device do we have ready for intracranial HTN
suction for vomiting
127
what kind of emergence do we want for intracranial HTN
smooth
128
what do we elevate HOB at for intracranial HTN
HOB >30*
129
what anesthetic agents increase Cerebral vascular resistance
thiopental, propofol, etomidate
130
T/F keep neuro patients hypothermic
true
131
T/F use PEEP in neuro patients
false
132
what anesthetic agents do NOT reduce electrical activity
nitrous
ketamine
133
what is the effect of N2O on brain
increases CMR, CBF, and ICP, can cause bubbles in brain
134
what is effect of lidocaine on brain
decreases CMR, CBF, ICP, is neuroprotective
135
what patients do we avoid lidocaine in
seizure patients
136
T/F use flumazanil/romazicon in neuropatients
be cautious, lowers neuroprotection
137
T/F use naloxone/narcan in neuro patients
be cautious, lowers neuroprotection
138
what is the effect of most vasodilators on brain
cerebral vasodilation and increases CBF
139
what effect does SUCCS have on brain
increases ICP
140
what monitors brain waves
EEG
141
what type of patients have EEG monitors
stroke
142
what is frequency on EEG
time between impulses
143
what is amplitude on EEG
peak to peak measurements on verticle plane, measured in microvolts
144
what are the worst 3 waves on EEG getting worse
Delta waves
burst suppression
isoelectricity
145
what is an early warning sign on EEG of declining neuro health
delta waves
146
what can a bolus of anesthetic drugs lead to
burst suppression- communicate to team before you bolus
147
what waves are on normal EEG
Beta and alpha waves
148
what happens with early onset of ischemia/hypoxia on EEG
theta and delta waves
149
what happens with increased hypoxia on EEG
delta waves
150
what happens on EEG with worsened hypoxia
burst suppression
151
what kind of waves happen with closed eyes and deep relaxation
alpha waves
152
what kind of waves happen with normal awake consciousness
beta waves
153
what kind of waves happen with light sleep
theta
154
what kind of waves happen with deep sleep
Delta waves
155
what do you communicate to OR team before induction
bolusing drugs, may see delta waves
156
how does epilepsy appear on EEG
high voltage spikes with slow waves
157
how does ischemia appear on EEG
slowing frequency with preserved amplitude
158
how do anesthetic agents appear on EEG
similar to global ischemia or hypoxemia (slowing frequency with preserved amplitude)
159
what MAC of des and sevo leads to burst suppression
1.2
160
what MAC of iso leads to bust suppression
1.5
161
how does low dose volatile effect EEG
increases Beta waves, some alpha waves
162
how does moderate dose volatile effect EEG
only beta waves
163
how does high dose volatiles effect EEG
delta. and theta waves
164
what two IV anesthetics lead to burst suppression
propofol and etomidate
165
how does large dose of opioids effect EEG
slow delta waves
166
T/F muscle relaxants effect EEG
false
167
what is technology behind cerebral oximeter
neat infared spectoscopy measures light absorbance to calculate oxy-hemoglobin deoxyhemoglobin
indirectly measures brain activity
168
what does cerebral oximeter detect/monitor
decrease in CBF in relation to CMRO2
169
what kind of blood does cerebral oximeter measure
venous
170
how do you set up cerebral oximeter
1. alcohol prep
2. pad on either side of head
3. mark baseline
4. start O2
171
what change do we watch for in cerebral oximeter or that causes alarm
20% change
172
what procedures do we do SSEPs for?
usually spinal cord
173
what is a 50% decrease in amplitude or a 10% increase in latency indicative of for SSEPs
possible ischemia (decreased blood flow to spinal cord )
174
what is effect of volatiles and barbiturates on SSEPs
increase latency and decreased amplitude
175
what is anesthetic plan for enoke potentials
TIVA, dont use NDMB
propofol and remi good option
precedex good option
can use anectine for intubation
176
when do we notify surgeon about Evoke potential numbers
50% decrease in amplitude or 10% increase in latency
177
what do evoke potentials help us detect
ischemia to spinal cord or cerebral cortex
178
what are examples of neuroprotective drugs (decrease CMRO2)
propofol
179
what are epileptogenic drugs to avoid
lidocaine
phenergan
robaxin
demerol
180
what are drugs that increase ICP
anectine increases by 5 mmHg
ketamine
181
what drugs cross the BBB (limit use of these
Benadryl
scopolamine
atropine (use robinol instead)
182
what drugs do we avoid that cloud sensorium
benzos
183
what drugs depress immune protective mechanisms
N2O, etomidate
184
what drugs increase cerebral steal?
nitroprusside and nitroglycerin, so use nicardipine instead
185
what drugs do we utilize that decrease the risk of intracerebral arterial vasospasms
nicardipine
magnesium sulfate
186
why do avoid narcotics in brain cases
brain has no pain receptors
187
what medications do we use to treat autonomic responses in neuro cases
propofol
esmolol
188
what part of head has pain receoptors
skin
189
when do we give opioids in neurocases
with emergence/closure of head
190
what medications can we give to decrease ICP
hypertonic Na
mannitol
lasix
191
what do we monitor with mannitol and lasix
electrolytes
UOP
BP
192
what is goal of fluid management of neuropatient
minimize neuronal injury
maintain organ perfusion
193
T/F inhalational anesthetics effect brain more than IV drugs
true
194
T/F N2O and ketamine decrease CMR
false
195
what is brain protective MAP
60-160
196
how can we manipulate CO2 to increase cerebral blood flow
hypoventilate to increase CO2 and vasodilate
197
how can we manipulate CO2 to decrease blood flow and ICP after giving ketamine
ketamine increases ICP
hyperventialte to decrease CO2
vasoconstrction
decrease ICP
198
what are effects of ISO, DES and SEVO on
CMR
CBF
ICP
decrease CMR
increase CBF
increase ICP
199
what is effect of barbiturates, etomidate, propofol, benzoson
CMR
CBF
ICP
decreased CMR
decreased CBF
decreased ICP
200
what is effect of ketamine on
CBF
ICP
increase CBF
increase ICP
201
what is the best volatile for Neuro
iso
202
what inhaled anesthetic do we avoid for neuro
N2O
203
what is the most common reason to have high ICP with succs
light anesthesia
204
what do we want ICP to be at before we open dura
lower
205
what can happen if ICP is high when dura is opened
herniation
206
what diuretics do we give to lower ICP
mannitol 0.25-1 g/kg followed by furosemide for up to 6 hrs
207
what is goal of BP during neuro case
normovolemia
MAP within 20%
208
what is goal serum osmolarity for neuro
305-320
209
what can cross the BBB
water, O2, glucose
210
what cannot cross the BBB
Na, Albumin, HCO3
211
what can happen with severe fluid restriction
hypovolemia
hypotension
decreased CBF
ischemia to brain and organs
moderate decrease in brain H2O
decreased tissue perfusion and oxygenation
decreased serum pH (hyperventilate to prevent acidosis)
monitor UOP, HR, BP
212
what can excessive hypervolemia lead to
HTN
cerebral edema
213
when do we want patient to be in a dehydrated/hypovolemic state
space occupying legions
CSF drainage/production problem
cerebral swelling with increased ICP
cerebral aneurism
214
how do we manage patient in a hypovolemic state
fluids on a microdrip, turn fluids off immediately after induction drugs
215
why dont we fully replace fluid in neuro cases
save space for blood replacement at end of case
216
what do we monitor for fluid balance
UOP
HR
BP
electrolytes
217
when do we want hypervolemia in neuro
cerebral aneurism repair
prevent vasospasm
218
when do we give patient fluids to make a hypervolemic state to prevent vasospasm
before dura is open be fluid sparing to keep ICP down, same during procedure
after aneurism is clipped ask surgeon if we can increase fluid to avoid vasospasm
219
what are the three Hs for cerebral aneurism repari/vasospasm prevention
hypervolemia
hypertension
hemodilution
220
what types of patients do we use hypertonic saline on
mass effects, midline shifts, high risk for post op cerebral edema, recipients of osmotic diuretics
221
what are hyponatremic patients at risk of
brain herniation
222
what are doses of hypertonic saline
50 ml/hr of 3%
30 ml/hr of 7.5%
223
at what sodium level do we give hypertonic saline
<135
224
at what sodium level do we hold hypertonic saline
>150
225
T/F replace fluid deficit in neuropatient
False
226
what fluid do we use for management in neuro patient
NS (isotonic)
227
what do we replace UOP with in neuropatient
NS
228
what are potential areas of hidden blood loss in crani
blood loss in drapes and head bag, lots of irrigation, mannitol and lasix losing more fluids so monitor fluids and electrolytes when using these drugs
229
what is best way to monitor blood loss in nuero patient
get baseline hct and recheck
230
what is average blood loss of crani
1L
231
HCT drops ______ for every 100 ccs of blood loss
1
232
how much blood does a raytec hold
10-20 ccs
233
how much blood does a lp hold
50-100 ccs
234
what is risk of replacing fluid loss with NS
hyperchloremic metabolic acidosis
235
what do we watch closely with manntol and lasix
fluids and electrolytes
236
what do we want BS to be
150 and under
237
what is normal blood flow in brain
50 ml/100g/min
238
what blood flow is associated with failure and structural damage
less than 20-25 ml/100g/min
239
when is dehydration needed in neuro
-space occupying lesions
-csf drainage/production problem
-cerebral swelling w/increased icp
-cerebral aneurysms
-when there is need to save space for blood product admin
-post op swelling anticipated
240
what labs should be monitored hourly for acid base status
base deficit
pH
HCO3
241
what should be monitor continously for fluid balance
UOP
HR
BP
242
how do we manage fluid for heads
npo defecit not replaced, caution fluid because of increased icp with dural opening
243
how do we manage fluids for spines
give a little fluid preop, then give albumin in or, and then gauge replacement based on uop, blood loss, bp, hr, etc.
244
what is positioning consideration for spines
prone so fluid goes to eyes, be conservative
245
what drugs do we avoid in neuro
lido
phenergan
robaxin
demerol
succs
ketamine
benadryl
scopolamine
atropine
benzos
N2O(crani)
etomidate
nitroprusside
nitroglycerin
246
what is latency on SSEP
time for evoke response to be measured in brain
247
what is effect of most anesthetic drugs on SSEPs
decrease amplitude, increase latency
248
what neuron function is motor
multipolar
innervate/control effector muscles and glands
249
what neuron function is sensory
psuedomonipolar
receive exteroceptive, interoceptive, and proprioceptive input
250
what neuron function is interneurons
pseudounipolar
connect to an adjacent neurons
251
what is grey matter
neuron cell bodies in the CNS
252
what is white matter
myelinated axons
