Sams Monitoring/Surg Notecards Flashcards

1
Q

What are the two different classifications of neuro monitoring?

A

Blood Flow/Metabolic

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2
Q

Name 3 blood flow monitors?

A

Cerebral oximetry
Transcrania doppler
Jug Bulb Venous O2 saturation

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3
Q

Name 4 nervous system function monitors

A
EEG
SSEP
BAEP
VEP
MEP
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4
Q

What law estimates brain tissue saturation?

A

Beer–lambert

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5
Q

Beer lambert law devise that detects decreases in CBF in relation to CMRO2?

A

Cerebral Oximetry Near–Infrared Spectroscopy

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6
Q

Name 5 things that change accuracy of cerebral oximetry

A
BP
PaCO2
Hgb
Regional blood flow
Scalp O2
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7
Q

Measure NIRS initially when?

A

Prior to induction

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8
Q

What is your goal in maintaining NIRS during surgery?

A

75% of baseline

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9
Q

When is NIRS used the most? 2nd most?

A

Carotid surgery

Cardiac surgery

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10
Q

Normal cerebral venous O2 saturation?

A

60–80%

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11
Q

Limitation of NIRS?

A

ONly measures regional oxygenation

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12
Q

What rule says that the depth of tissue being measured by NIRS is directly proportional to the distance between the LED and sensor?

A

Spatial Resolution

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13
Q

NIRS monitors what lobe?

A

Frontal

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14
Q

Do electrocautery interfere with NIRS?

A

Yes

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15
Q

What displays the difference between regional O2 and baseline?

A

Delta Base

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16
Q

What index quantifies that depth and duration of patient staying under user–define rSO2 limit alarm?

A

Area Under Curve (AUC)

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17
Q

What is shorthand for NIRS tissue oxygen saturation?

A

rSO2

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18
Q

What displays the differnce between SpO2 and rSO2?

A

Delta SpO2

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19
Q

The top number in NIRS is the _ side of the head.

A

Left

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20
Q

Trancranial doppler ultrasonography measures _____ not ______.

A

Velocity not Volume

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21
Q

Narrowed segments of blood will show increased ________ even though there is lower volume of blood traversing.

A

Velocity

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22
Q

TC Doppler is MOST commonly positioned over the _______ to monitor the ______.

A

Temporal Bone

MCA

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23
Q

Would increased temporal bone thickness mess with your doppler?

A

Yes

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24
Q

Where does the doppler measure blood flow velocity?

A

Circle of Willis

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25
What monitor provides information regarding flow direction, peak systolic and end–diastolic velocity, flow acceleration time, intensity of pulsatile flow, and detection of microemboli?
Doppler
26
Doppler on the base of the neck monitors the ____ artery.
Basilar
27
How much blood flow does the jugular bulb drain from the ipsilateral side?
70%
28
What is the dominant IJ in most patients? What does it drain?
Right Cortical blood
29
What is the non–dominant IJ in most patients? What does it drain?
Left Subcortical
30
Where is the jugular bulb accessed?
1cm below and 1cm anterior to the mastoid process.
31
The jugular bulb is near what sinus?
Sigmoid
32
SjvO2 monitors for ischemia in patients with increased _____. Maintenance goal percent?
ICP 55–75%
33
Is the SjvO2 the same bilaterally?
no
34
SjvO2 less than 55% indicates what 2 things
Inadequate delivery | Excessive consumption
35
SjvO2 greater than 75% indicates what 2 things?
Hyperemia | Stroke
36
EEG only monitors what structures?
Cortical (outer 2–3cm)
37
3 basic components of EEG?
Frequency Amplitude Morphology
38
EEG measures the difference of _____ between groups of neurons
Electrical Potentials
39
Will ischemia be detected in the subcortex or spinal cord by EEG?
No
40
List of EEG waves from fastest to slowest?
``` Gamma Beta Alpha Theta Delta ```
41
What is my mnemonic for remembering the EEG waves from high to low?
Go Buy A Truck Dear
42
_____ waves signal the potential for increased ischemia and ischemic damage
Delta
43
What wave initially occurs when the brain expereinces ischemia? What increases after that?
Beta Amplitude
44
After beta waves and amplitude increase, what waves appear during ischemia?
Theta and Delta
45
Which style of anesthetic depresses EEG more at equal doses?
Inhalation
46
Inhalation agents increase the ______ and decrease the _____ of EEG waveforms at low and moderate doses
Increased frequency Decreased Amplitude
47
Just like inhalation agents, induction doses of etomidate, propofol, and ketamine cause _____ waves at low and moderate doses?
Beta
48
Once stage 3 anesthesia is reached, frequency is _____ and amplitude is _______
Frequency lower | Amplitude Higher
49
Which anesthetic produces no theta and delta waves, just high oscillation waves?
Ketamine
50
Delta waves are mostly if the patient is very _____
Deep
51
What type of wave is usually evident at a full anesthetic depth?
Theta waves
52
Gamma hz?
30–100
53
Beta Hz?
10–30
54
Alpha hz?
8–15
55
Theta hz?
4–8
56
Delta hz?
0.5–4
57
``` Which EEG waves occur with: Heightened perception Learning Problem solving tasks Cognitive processing ```
Gamma waves
58
``` Awake Alert Conscious Thinking Excited ```
Beta waves
59
Physically and mentally relaxed waves
Alpha
60
Creative, insightful, dreaming, meditating, reduced consciousness?
Theta waves
61
Deep sleep without dreams, loss of bodily awareness, repair?
Delta waves
62
True or false: Etomidate and prop can cause burst suppression
TRUE
63
Burst suppression occurs with Iso at ____ MAC.
1.5
64
Burst suppression occurs with Sevo or Des at _____ MAC.
1.2
65
Is BIS more predictive with inhalation?
Yes
66
BIS less than _____ reflects low probability of recall
60
67
What lobe does BIS look at
Frontal
68
GA BIS?
40–60
69
Awake BIS
80–100
70
Mild/mod sedation BIS?
60–80
71
Deep hypnotic BIS?
20–40
72
Burst suppression BIS?
Less than 20
73
Flat line EEG BIS (lack of brain activity) value?
0
74
True or False: BIS values under 40 for greater than 5 minutes increases mortality
TRUE
75
What anesthetic produces falsely high BIS at appropriate levels of anesthesia?
Ketamine
76
Mechanical stress to brain?
Retraction
77
Loss of functional intergity of brain?
Transection
78
Ligation, edema, or vessel damage to the brain causes?
Ischemia
79
Heat to the brain is caused by?
Cautery
80
T or F: Anemia, hypothermia, hotn, and positioning affect evoked potentials
TRUE
81
3 evoked potentials monitor _ function
Sensory
82
_____ decrease in amplitude or ______ increase in latency is indicative of CNS ischemia?
50% amplitude 10% latency
83
Positive and neg deflection on EPs are what letter? What number is listed by them?
P N Time until response (latency)
84
Which EP detects localized injury to specific area of the neural axis by assessing cortically generated waves?
SSEP
85
Can SSEP serve as a non–specific indicator of adequacy of cerebral oxygenation?
Yes
86
The main purpose of SSEP is to evaluate the integrity of the brain or _________
Spinal cord
87
SSEP specifically monitors the _______ and ______ tracts of the dorsal lemniscal system.
Cuneatus Gracilis
88
The cunateus is more ______, while the gracility is more _______.
Cuneatus = Lateral Gracilis = Medial
89
SSEP is altered if brain or ______ spinal cord ischemia occurs
Posterior
90
Which lemnicscal system monitors the cervical and thoracic regions?
Cuneatus
91
The fasciculus gracilis measures the _____ and _____ regions
Sacral and Lumbar
92
SSEPs monitor integrity of the ________ cortex.
Somatosensory
93
What three sensations does the dorsal lemniscal tract carry?
Discrete Touch Vibration Proprioception
94
Where do the first order neurons synapse with second order neurons in the dorsal lemniscal system?
Nucleous Gracilis/Cuneatus
95
Where do second order neurons of the dorsal lemniscus system synapse with third order neurons?
Thalamus
96
SSEP stimulating electrodes are placed ______
Peripherally
97
Most common 2 nerves for SSEP stimulating electrode?
Posterior Tibial Median
98
Backup nerve sites for SSEP stimulating electrodes?
Common Peroneal Ulnar
99
Primary SSEP detecting electrodes are on the ______. Secondary recordings are on the _____
Scalp Spine
100
Where do you record a nerve itself peripherally for verifying stimulation of SSEPs in the lower extremity?
Iliac Crest
101
Where do you record a nerve itself peripherally for verifying stimulation of SSEPs in the upper extremity?
ERB's point
102
What body part is Erb's point located
Neck
103
SSEP latency increases 3ms for every 2 degree ______ in temp
Decrease
104
________ suppreses SSEP amplitude to 15% of normal
Hyperthermia
105
Which 2 anesthetics increase SSEP amplitude 2–6x?
Ketamine and Etomidate
106
With SSEP's avoid ________ of anesthesia which could be confused for ischemia
Boluses/changes
107
What CN does BAEP monitor
CN 8 Vestibulocochlear | also for brainstem surg
108
What evoked potential is least sensitive to anesthesia?
BAEP
109
The only non–damange factor the increases latency of BAEP?
Hypothermia
110
What happens to BAEP as temp increases?
Amplitude Increases
111
Electromyography senses mechanical and thermal damage to what CN?
7 (facial)
112
Standard of care for acoustic tumor surgery
Electromyography
113
What CN can electromyography measure
3, 4, 7, 10, 11, 12
114
What should you avoid when doing electromyography facial nerve monitoring?
Muscle relaxants
115
____________ monitor optic chasm, optic nerve, retina to occipital cortex?
VEP
116
Patterned flash VEP's are used on _____ patients.
Awake
117
_______ flast VEPS via goggles are contacts are used under anesthesia
Unpatterned
118
When do you have to cover the contralateral eye for VEPs?
Monocular
119
_____ are rarely used under anesthesia because stable recordings vary among patients
VEP
120
MEPs assess the ______ spinal cord and __________ tract.
Anterior Corticospinal
121
Volatiles and NMB suppress MEPs. Avoid NMB to a level greater than ____ reduction in height of ulnar nerve response.
70%
122
Best anesthetic for MEPs?
TIVA (prop, ket, narc)
123
List the most affected evoked potentials to the least.
VEP>MEP>SSEP>BAEP
124
MEPs are mostly used during _____ procedures
Spinal
125
Where is the stimulating electrode placed for MEPs?
Centrally (motor cortex, SC)
126
Use less than ____ MAC for SSEP or MEP
0.5
127
What is avoided for MEPs w/ PPM, bladder/spinal stimulator, previous crani, metal in body?
Magnetic stimulation
128
How to remember anestehtic effects on evoked potentials
Very affected Moderately affected Somewhat affected Barely affected
129
First compensatory mechanism for increased ICP
CSF absorption or shunt to SC
130
What occurs initially when volume compensating mechanisms reach exhaustion in skull
Local Ischemia followed by global
131
What cerebri separates L and R hemisphere?
Falx
132
What separates the supratentorial and infratentorial space
Tentorium Cerebelli
133
What type of herniation occurs at the singulate gyrus under the falx cerebri and causes midline shift?
Subfalcine
134
What type of herniation occurs at the uncinate gyrus through the tentorium cerebelli which causes brainstem compression?
Transtentorial
135
Altered consciousness, sight and ocular reflex issues, respiratory and cardiac function would b cause when the ______ gyrus goes through the _________
Uncinate Tentorium
136
What subtype of transtentorial herniation is associated with oculomotor nerve dysfunction
Uncal
137
What type of herniation results from increased infratentorial pressure causing extension of cerebellar tonsils through the foramen magnum?
Tonsillar herniation
138
Tonsilar herniation would cause _______ instability due to pressure on the _______.
Cardiorespiratory Medulla
139
_______ or _______ herniation is any area beneath a defect of the skull or going through the skull?
Transcalvarial External
140
Gold standard for ICP
Intraventricular (ventriculostomy
141
Lumbar drainage of CSF in the setting of brain tumore may lead to ____ herniation.
Tonsillar
142
Does lumbar pressure always reflect brain?
No
143
Which 2 devices allow monitoring and csf drainage
Lumbar SAC | Ventric
144
Ventriculostomy is zeroed _____ with the jugular ______ at the level of the ______.
Daily Foramen Tragus
145
Can ventrics be set to only drain when pressure gets to a certain value?
Yes
146
What type of drain would be used for ICP monitoring for a pituitary surgery with difficult access
Lumbar
147
The most common complication of ICP monitoring?
Infection
148
Infection is increased when ICP ismonitored more than ___ days
5
149
First peak of ICP (P1)
Arterial pulse
150
Second peak of ICP (P2)
Cerebral Compliance
151
3rd peak of ICP (P3)?
AV closure, dicrotic notce
152
P1 is a ____ wave, P2 is a _____ wave, P3 is a _____ wave.
Percussive Tidal Dicrotic
153
Intracranial HTN is when ____ is greater than P1.
P2
154
______ is the inverse of compliance
Elastance
155
What is the lundberg A wave?
Plateau wave
156
Lundberg A waves last up to ___ minutes with an ICP of _____. They indicate increases ________ or decreased _______.
20 20–100 Elastance Compliance
157
Lunberg A waves have _______ outcomes due to ____________ ischemia.
Poor, global
158
What wave would be seen during cushing's triad?
Lundberg A
159
Cushing's triad?
HTN (wide PP) Bradycardia Irregular respirations
160
Sharp brief P2 spikes when ICP is 20–50
Lundberg B
161
Rhythmic benign short duration spikes when ICP is less than 20
Lundberg C
162
ICP is treated when it reaches____
20
163
Primary symptom of IC HTN
HA
164
When ICP exceeds 30, CBF _____ which can lead to brain herniation vicious cycle
Decreases
165
3 ways tumors increase ICP
Size Edema Obstructed CSF flow
166
Congenital narrowing of the cerebral aqueduct of sylvius between the 3rd and fourth ventricle
Aqueductal stenosis
167
Main sx or aqueductal stenosis
Seizure
168
For aqueductal stenosis, CT or MRI will show enlarged ______ ventricle and normal ____ ventricle due to hydrocephalus
3rd 4th
169
Treatment for aqueductal stenosis
Ventricular Shunting
170
Pseudotumor cerebri?
Benign intracranial HTN
171
Obsese women w/ menstrual irregularities, SLE, PCOD, addison's or hypoparathyroidism, during pregnancy?
Benign ICH
172
Acute treatment of benign ICH?
CSF removal acetazolamide Corticosteroids
173
How much CSF do you remove for benign ICH (pressure over 20)
20–40cc
174
2 symptoms of benign ICH
HA, visual change
175
Side effect of acetazolamide ICH treatment
Acidemia
176
Is acetazolamide a good drug for acute benign ICH treatmetn?
No, more chronic
177
Avoid ____ and _____ when treating benign ICH
Hypoxia and hypercarbia
178
If a patient has benign ICH w/ lumboperitoneal shunt, what type of anesthsia is avoided?
Spinal (less effective_ | Epidural (dangerous)
179
4 subcompartments of intracranial space
Cellular (surgeon) CSF (drainage) Fluid (Osmotics, diuretics, steroids) Blood (venous and arterial)
180
Not recommended to remove CSF in patients with risk of ____ or _____ herniation
Transtentorial | Tonsillar
181
What intracranial subcompartment can we control most during surgery
Venous blood
182
All volatile agents ______ ICP, CBV, and CBF
Increase
183
Because volatiles causes systemic vasodilation and increased CBF, what will happen to CPP?
Decreased!
184
CMRO2 is decreased and autoregulation is impaire around _________ MAC.
1
185
CMRO2–CBF uncoupling occurs at _____ MAC
0.6–1ish
186
Order the volatiles that increase CBF from greatest to least?
Des Sevo Iso
187
What gas increases absorption of CSF
Iso
188
Volatile agents are _____ in global ischemia
Beneficial
189
Volatile agents are _______ in focal ischemia due to steal phenomenon
BBad
190
Iso breaks the rule because it affects CBF the least, but it double CBF if you get to _____ MAC
1.5
191
True or false: N2O increases CBF and CMRO2
TRUE
192
N2O doubles CBF at ___ MAC
0.5
193
What gas causes •Prolongedaccumulation of metabolic breakdown products can lead to megaloblastic anemia,leukopenia, impaired fetal development, and a depressed immune system (inhibitionof methionine synthase co–factor ofvit B12)
N2O
194
Does N2O impair autoregulation on its own?
NO. Only when with gas
195
N2O is ___ soluble than nitrogen
More
196
All agents excepts ketamine ________ CMRO2, CBF, and ICP
Decrease
197
Good drug for wake up tests
Dex
198
What induction drug decreases production and enhances absorption of CSF
Etomidate
199
Why does etomidate maintain CPP better than prop
Less MAP decrease
200
Most widely used induction agent in neuro anesthesia
Propofol (Seizure suppression)
201
When is etomidate not your first choice in TBI
Adrenal supression
202
Do opioids mess with CMRO2, CBF, ICP?
Not too much
203
Which opioid can activate sizures, decrease MAP and CPP
Alfentanil
204
Which opioid to not use in neuro surgery because it causes seizure
Meperidine
205
Large doses of flumazenil cause _____
Seizures
206
Do benzos reduce CBF, ICP?
Dose dependent
207
Opioids are mild cerebral ________
Vasoconstrictors
208
How do you reverse demerol seizures?
Slow narcan
209
Ketamine won't increase ICP if given with GABA agonist like prop or midazolam?
TRUE
210
Is ketamine a good sole agent in neuro
No
211
Do NDNMB affect brain
No
212
Does sux increase ICP, CBF, CMRO2?
Yes
213
What 2 NDNMBs to avoid in neuro
Panc, atracurium
214
Are sodium NTP and NTG safe in pateitns with abnormal elastance?
NO, avoid
215
Inhalation agents _____ CBF, IV agents ________ CBF
Increase Decrease
216
All anesthetics/opioids ___________ CPP
decrease (or stay the same)
217
Inhaltion agent ______ ICP, while IV ________
Increase Decrease
218
First line goal value of hypocapnea
30–35
219
2nd line goal of hypocapnea
25-30
220
Does ICP decrease more when you decrease CO2 below 20?
No
221
You can't do hyperventilation and hypocapnea within 24 hours of ________
TBI
222
When you hyperventilate and decrease PaCO2, CBF returns to it's starting value after about ______ hours.
8
223
What alters the concentration of bicarb in the CSF and brain ECF to cause pH to normalize?
Carbonic Anhydrase
224
Communicate BP goals with _____ prior to surgery.
Surgeon
225
Clinical improvement of steroids is usually seen within ____ hours.
24 hours
226
True or false: ICP may not be reduces until 2–3 days after you start steroids?
TRUE
227
Start steroids _______ hour priop to reduce edema formation and improve conditions
48 hours
228
Most common dosing for decadron preop
4mg Q6hours
229
Steroids for TBI patients is _______
Contraindicated
230
Can you decrease intra–op edema by giving the first dose of steroids on induction
No
231
Most common and effective osmotic diuretic
Mannitol
232
Mannitol dose range
0.25–1g/kg over 10–15 minutes
233
``` Manittol Removes ___ ml Decreases ICP in ___ minutes Max effect ____ hours Duration ____ hours UOP _____ ```
``` 100ml 30 2 6 1–2L/hr ```
234
True or false: Give mannitol rapidly
False, causes vasodilation and increased ICP
235
What do you give mannitol with to increase excretion of water from intravascular space and decrease rate of CSF formation
Loop diuretic
236
When does mannitol make ICP worse?
Ruptured BBB
237
What type of patient would you give lasix with mannitol
CHF
238
What metabolic state does mannitol cause
Hypokalemic Hypochloremic metabolic alkalosis
239
Make sure you monitor ____ when on mannitol
Electrolytes
240
What % of saline has similar effects on iCP at 2 hours?
3%
241
You usually give 3% as a infusion, but what dose can you bolus over 5 minutes?
1–2ml/kg
242
What happens if you raise Na more than ___ meq in 24 hours?
9 Central pontine myelinolysis
243
Keep serum osmolarity under ________
320
244
What can be done to manage ICH refractory to other methods because it decreases CMRO2, hyperthermia, and convulsions?
Barbituate Coma
245
First line therapy for barbituate coma hotn?
Volume followed by pressors
246
What is high anion–gap metabolic acidosis caused by?
Propofol infusion syndrome
247
Barbituate coma interferes with neuro eval and causes ________ on EEG
Burst suppression
248
BG goal
140–180
249
Injuyred brains often become _____ due to localized hyperglycolysis.
Hypoglycemic
250
Should patients get tight blood sugar control in acute severe injury?
Nah
251
Hyperglycemia ______ ischemic insult
Worsens
252
In TBI, you should only really treat if over 250 or 200 consistently ok?
Ya dog
253
_______ is best utilized in patietns at high risk of intraop ischemia due to quesitonable efficacy
Mild hypothermia (34–36)
254
2 risks of controlled hypothermia
Coagulopathy | Dysrhythmia
255
Esophageal, tympanic, PA, and jugular venous bulb are good for _______ monitor
Deep brain temp
256
NS osmolarity and side effect
308, hyperchloremic metabolic acidosis
257
LR osmolarity and side effect
274, can cause cerebral edema by lowering osmolality
258
Plasma osmolariy
290
259
You basically want to maintain normovolemia and MAP during surgery ok
OK
260
UOP goal
0.5–1ml/kg/hr
261
Maintain Hct above _____
28%
262
Dextran interferes with ____ function
Platelet
263
Hetastarch causes dilutional reduction of coagulation factors, inhibiton of platelets and factor ______
8
264
10–20 degree semilateral table tilt with shoulder roll?
Jannetta position
265
What position is used for access to posterior parietal and occipatal lobes and lateral posterior fossa?
Axillary (use ax roll to prevent BP injury)
266
You should avoid neck ____ during surgery.
Flexion
267
Concorde position?
Prone
268
Most frequent cause of prone POVL?
Ischemic optic neuropathy (central retinal vessel occlusion)
269
Wilson frame, low ABP, low Hct, male, obese, long surgery, large volume leads to increased _____ risk
POVL
270
Why can prone position cause increased bleeding during spine surgery
IVC compression, epidural engorgement
271
In the sitting position, pressure transducers should be referenced at the ____
External auditory meatus
272
Macroglossia, quadriplegia, and pneumocephalus are exacerbated by what position
Sitting
273
1cm difference in height = _________ mmHg change in BP when in the sitting position
0.78
274
Distance from heart to EAM in sitting position
15cm
275
CPP should be maintained at _________ in healthy patients in sitting position
60
276
CPP should be at least ______ in elderly, HTN, CVD, cervical dz, decreased spinal cord perfusion, sustained retractor pressure
70
277
Chronic HTN cause ______ shift on autoregulation curve
Right
278
Sustained _______ pressure is an opposing force to blood flow
Retractor
279
PA cath is used ________. A–line is used _____. CVC is used ______.
Rarely Always Usually
280
Complsitting position that occurs secondary to stretching or compression of the cerpinal cord that may warrant the use of SSEP monitoringication of
Unexplained quadriplegia
281
What is the absolute contraindication to sitting position?
Intracardiac shunt (PFO, VSD)
282
Unexplained quadriplegia is caused by neck _______
Flexion
283
Relative contraindication of sitting positions?
Degenerative cervical spine/CVD
284
What happens during posterior fossa surgeries in the head up position when air enters the supratentorial space? An air pocked in the skull.
Pneumocephalus
285
Delayed awakening after posterior fossa or supratentorial surgery can be cause by ________
Pneumocephalus
286
Pneumocephalus dx
Brow up lateral CT/XR
287
Pneumocephalus treatment?
Drill hole and needle puncture of dura
288
2 times VAE most commonly occurs
Posterior Fossa Upper cervical spine (in sitting position)
289
40% of ______ patients get VAE
Posterior fossa
290
12% of ____ pateitns get VAE
Cervical spine
291
It is a good idea to lower the patient out of the sitting position _________ you take them out of the head holder.
Before
292
2 most common sources of critical venous air entry
Sigmoid and Sigittal sinus
293
VAE results from _____ pressure gradient between the operative site and right side of the heart
Negative
294
Venous pressure at wound level is usually ______
Negative
295
Most common way VAE travels?
Into pulmonary circulation, diffuses out of alveloi and is exhaled
296
VAE may collect at the _____________
Cavoatrial junction
297
VAE will rarely transverse the pulmonary capillaries and enter ________ circulation.
Systemic
298
What percent of patients have PFO
30%
299
Paradoxical air embolus occurs when _______ heart pressure exceeds __________
Right, Left
300
What should you do for patients who have a murmur and are gonna have sitting position
Echo
301
Avoid the use of ____ in patients with VAE
PEEP
302
VAE endothelial mediators produce a reflex pulmonary ______.
Vasoconstriction
303
What causes RV failure and decreased CO in VAE
Air–lock
304
Obstructed pulmonary blood flow causes what kind of VQ deal
Dead Space Ventilation
305
Air that enters the PA can trigger reflex ________ and pulmonary ______.
Bronchospasm | Edema
306
Air in alveoli may be detected by presence of ET _______
Nitrogen
307
How much VAE causes decreased ETCO2, Increased ETN2, oxygen desaturation, AMS, and wheezing?
Less than 0.5 ml/kg
308
What amount of VAE causes difficulty breathing, wheezing, hypotension, ST changes, peaked P waves, JVD, MI, bronchonstriction?
0.5–2ml/kg
309
What amount of VAE cause CP, RV failure, CV collapse, pulmonary edema
Greater than 2ml/kg
310
Hypotension, tachycardia, dysrhythmia are ______ signs of VAE
Late
311
Order of sensitivty for VAE detection
``` TEE Doppler PA/ETCO2 CO/CVP BP, EKG, Precordial detection ```
312
Where is the precordial doppler placed for VAE
R sternal border between 3–6th ICS
313
Late sign of air entrainment on precordial doppler
Mill–wheel
314
PA cath is slightly more sensitive than ETCO2 when _____ is greater than _______
RAP > PCWP
315
Doppler can detect as small as ______ml/kg air for VAE
0.002
316
How to check for proper VAE doppler position
Inject 10ml in CVC and listen
317
The first sign of VAE for patients on controlled ventilation when they suddenly attempt to breathe spontaneously?
Gasp Reflex
318
What increases cerebral venous pressure and induces bleeding when treating VAE (good)
Bilateral jugular compression
319
Position for VAE treatment?
Durrant | Trendelenber, left lateral
320
50% N2O will ____ an air bubble size
Double
321
70% N2O will ________ an air bubble size
Quadruple
322
True or false: PEEP and Valsalva are recommended to treat VAE?
FALSE. They are bad
323
Durrant position traps air in the __________.
RA