Spinal and epidural Flashcards
(332 cards)
1
Q
What are the clincal indications of spinals/epidurals
A
surgical procedures involving lower abdomen, perineum, and lower extremities
2
Q
What types or surgeries are common indications for spinal/epidural
A
-Orthopedic surgery
-Vascular Surgery on legs
-Thoracic surgery(adjunct to GA)
3
Q
What are some benefits of neuroaxial anesthesia?
A
1.) Less narcotic usage
2.)Less postoperative ileus
3.) less thromboembolic events
4.) Less PONV
5.) less respiratory complications
6.) Less bleeding
4
Q
What are the relative contraindications of neuroaxial anesthesia regarding deformities of the spinal column?
A
-Spinal stenosis
-Kyphoscoliosis
-Ankylosing sponylitis
5
Q
What pre-exisiting spinal cord diseases are relative contraindications?
A
Degenerating disease
Multiple sclerosis
Post polio syndrome
6
Q
What head problems can be a relative contraindication to neuroaxial anestheisa
A
Chronic headaches
Chronic back aches
7
Q
If you’ve attempted an epidural/spinal _____ amount of times it can become a relative contraindication
A
3 attempts
8
Q
What are the ABSOLUTE contraindictaions of neuroaxial anesthesia
A
Coagulopathy
Patient refusal
Evidence of dermal site infection
9
Q
Regarding absolute contraindications for neuroaxial, the specific contraindications regarding coagulopathy are
A
-INR> 1.5
-Platelets < 100,000 (consider trends)
2 results of PT, aPTT, bleeding times too high
-Known coagulation disorder or taking anticoagulants
10
Q
What pathway does heparin act on?
A
Intrinsic pathway
11
Q
What labs are used when observing the effectiveness of heparin
A
PTT, aPTT
12
Q
What pathway does Coumadin act on?
A
Extrinsic pathway
13
Q
What labs are used when observing the effectiveness of coumadin
A
PT, INR
14
Q
Regarding the heart valves, what issue is an absolute contraindication for neuroaxial anesthesia
A
Severe aortic stenosis
15
Q
Severe aortic stenosis is defined by a valve area of
A
<1cm2 to .7cm2
16
Q
Severe mitral stenosis valve area is defined as
A
< 1.0cm2 of valve area
17
Q
Other than aortic stenosis, what other heart pathology is a absolute contrindication
A
HSS (Idiopathic hypertrophic subaortic stenosis)
18
Q
Regarding the brain, what is an absolute contraindication of neuroaxial anesthesia
A
Increased ICP
19
Q
Is severe CHF an aboslute contraindication?
A
Yes. EF< 30-40%
Preload dependent
20
Q
Regarding the time of operation, what is an absolute contraindication
A
Operation time is > the duration of the local anesthetic
21
Q
What is the terminology regarding aortic stenosis that leads to hypotension following a epidural/spinal that leads to increased ischemia
A
DEATH SPIRAL
22
Q
How is onset of action different between spinal and epidural
A
Spinal: Rapid
Epidural: Slow
23
Q
How is the spread different between a spinal and epidural
A
Spinal: Higher than expected
Epidural: As expected, controlled with VOLUME of LA
24
Q
The nature of the block between spinal and epidural differs by
A
Spinal: DENSE
Epidural: Segmental
25
Motor block spinal vs epidural
Spinal: Dense
Epidural: Minimal
26
Hypotension post spinal vs epidural
Spinal: Likely
Epidural: Less than spinal
27
Onset time of spinal
5 minutes
28
Onset time of Epidural
slow (10-15 minutes)
29
Duration time spinal
Limited or fixed
30
Duration time of epidural
Unlimited
31
Placement level of spinal
L3-4, L4-5, L5-S1
32
Placement level of epidural
Any level
33
Dosing of spinal
Dose based (mg)
34
Dosing of epidural
Volume based
35
LAST with spinal
No
36
LAST with epidural
Yes
37
How does gravity influence spinal
Via baricity
38
How does gravity influence epidural
Via position
39
How is dermatome spread manipulated via spinal?
Position changes, Baricity
1st 5 minutes
40
How is dermatome spread manipulated via epidural
Incremental dermatome spread based on VOLUME, 1-2 mL per segment
41
How many vertebra are in the cervical column?
7
42
How many vertebra are in the Thoracic vertebra
12
43
How many vertebra are in the lumbar
5
44
How many vertebra in sacrum
5- fused
45
How many vertebra in coccyx
4- fused
46
Vertebra are divided into two parts
Anterior- Body
Posterior- Vertebral arch
47
What two structures connect the anterior and posterior segments
lamina and pedicle
48
What area of the spinal cord is formed that houses the spinal cord?
Vertebral Foramen
49
When comparing the different vertebra, why is the section important in determining where to place the spinal/epidural
The spinous processes are oriented different and make insertion with a needle more difficult
50
Which vertebra are the easiest regarding needle insertion?
Lumbar vertebra
51
Where do spinal nerves exit out the vertebra?
Intervertebral Foramina
52
When discs wear down, how does it effect the spinal nerves?
Foramina become smaller compressing spinal nerves
53
Where is the superior aspect of the iliac crest located?
L4
54
Where is the posterior superior iliac spine located?
S2
55
What is the line termed that runs horizontal across the top edges of the iliac crest and matches with the L4 vertebra
Intercristal Line (Tuffiers line)
56
The space above the intercristal line aligns with what vertebra
L3-L4 vertebra
57
The space below the intercristal line aligns with what vertebra
L4-L5 vertebra
58
In Infants up to 1 year, the intercristal line corresponds with what vertebra space?
L5-S1 intervetebral space
59
The Lamina of S5 is incomplete and bridged only by ____
Ligaments
60
What covers the Sacra hiatus?
Sacrococcygeal ligament
61
The ____ acts as an access point for caudal anestheisa
Sacral Hiatus
62
The projections on either side of the sacral hiatus that guard it
Sacral Cornua
63
What is used as the landmark for caudal anesthesia?
Sacral Cornua
64
What is the end of the spinal cord called?
Conus medullaris
65
In adults where does the conus medullaris end?
Between L1 and L2 vertebra
L1 IN MOST TEXTBOOKS
66
In infants, where does the conus medullaris end?
L3
67
What is the bundle of nerves that extend from the spinal cord called?
Cauda Equina
68
The cuada equina extends from
conus medullaris to the dural sac
69
The cauda equina exists of nerve roots from
L2 - S5 vertebra
70
Where does the subarachnoid space end?
The dural sac
71
The dural sac ends at ___ in adults and ___ in infants
S2, S3
72
Extends from the end of the spinal cord to the tailbone
Filum Terminale
73
The filum terminale is a continuation of the _______ _______
pia matter
74
What is the main function of the filum terminale?
Anchors the spinal cord to the coccyx
75
Two parts make up the filum terminale
1.)Internal Filum Terminale
2.)External Filum Terminale
76
The internal filum terminale extends from the _____ to the _____
Conus medularis
dural sac
77
The external filum terminale starts at the _____ and extends to the _____
dural sac
sacrum
78
Anterior spinal artery orginates from the ____
vertebral artery
79
Does the anterior spinal artery supply the motor or sensory portion
motor
80
The posterior spinal artery originates from the
cranial vault
81
How many posterior arteries are there
2
82
Does the posterior artery supply the motor or sensory portion of the cord
sensory
83
Which artery is a crucial connection that supplies blood to the lower two-thirds of the spinal cord
Artery of Adamkiewicz
84
At what level does the artery of adamkiewicz arise from?
T7-9 and L2 region
85
Spinal anesthesia is also termed _______ anesthesia
intrathecal anesthesia
86
Veins are located more so in the _______ aspect of the epidural space
Lateral
87
What are the epidural veins that form a plexus draining blood from the cord and its linings?
Batsons plexus
88
What is the possible presence of a connective tissue located between the ligamentum flavum and dura matter that can effect the spread of drug
Plica Mediana Dorsalis
89
What is the order of meninges from most superficial to deep?
1. Dura matter
2.) Arachnoid Matter
3.) Pia matter
90
How many pairs of spinal nerves are there?
31 pairs
91
How many spinal nerves are in the cervical vertebra?
8
92
Why is the C8 nerve an exception to the other cervical nerves?
It exits below the C7 vertebra vs the others (exit above the corresponding vertebra)
93
What fiber is afffected fist via spinal/epidural
B fiber
94
What fiber is affected second via epidural/spinal
C fiber
95
What fiber is effected last via epidural/spinal
A fiber
96
Which fiber is blocked the longest following an epidural/spinal
B fiber
97
Which fiber returns to noraml function first following a epidural/spinal
A-alpha
98
Which fiber returns to normal function last following epidural/spinal
B fiber
99
When monitoring a sensory block, in what order does the block affect sensory function
1.Temp
2. Pain
3. Touch/pressure
100
When monitoring a motor block, what is the name of the scale used?
Modified Bromage Scale
101
What major systemic affect does neuraxial anesthesia have on the CV system?
Reduces preload
102
Neuroaxial anesthesia reduces afterload by how much in a healthy person?
15%
103
In a diseased pt, how much does SVR decrease after neuraxial anesthesia?
up to 25%
104
Will cardiac output following neuraxial anesthesia decrease or increase initially?
Increase
105
Does heart rate decrease or increase following neuraxial anesthesia?
Decrease
106
What reflex causes bradycardia following underfilling of the ventricles from neuraxial anesthesia
Bezold-Jarisch reflex
107
The Bezold-Jarisch reflex is mediated by what receptors?
5-HT3 receptors
108
Where are the 5-HT3 receptors located that cause this bradycardia
On the vagus nerve and in the ventricular myocardium
109
The Bezold-Jarisch reflex is the opposite of what other cardiac reflex
Bainbridge Reflex
110
Because some young adults have high parasympathetic tone, it can result in what, following epidural/spinal anesthesia that affects the cardiac accelerator fibers
Cardiac Arrest
111
What is the ratio of young adults who experience cardiac arrest after a spinal
7:10,000
112
What is the ratio of young adults who experience cardiac arrest after a epidural
1:10,000
113
After how many minutes following a spinal does cardiac arrest occur in young adults
20-60 minutes after onset of spinal
114
Regarding preventive methods for spinal anesthesia hypotension, what meds can be given?
-Vasoconstrictors
-5-HT3 antagonist
-Fluids
115
Pre loading fluids with neuraxial anesthesia
Giving fluids prior to the spinal or epidural
116
Instead of pre loading, we routinely do this method to negate hypotension
Co- loading with fluids
117
When co-loading, how much do we give?
15ml/kg right after the spinal/epidural
118
Regarding fluid admin to negate hypotension following a spinal/epidural, what do we want to avoid?
Avoid excess fluid administration
119
Reguarding position change to negate hypotension following epidural/spinal, what specific pt is this usually done for
Pregnant pt. Left lateral pelvic tilting... Reduce the pressure on the inferior vena cava
120
When TREATING spinal induced hypotension, what vasopressors are commonly used
Ephedrine and epinephrine
121
Which drug is preferred if there is symptomatic bradycardia
Ephedrine
122
What anticholinergic can be used for spinal induced bradycardia?
Atropine
123
When using trendelenburg position for hypotension, greater than what degrees can reduce cerebral perfusion
>20 degree tilt
124
What lung volume changes in result of neuraxial anesthesia?
ERV
125
Is vital capacity increased or decreased with neuraxial anesthesia? why?
Decreased; Loss of abdominal muscle contribution in forced expiration
126
High thoracic blockade can result in blockade of what accessory muscles of respiration
Intercostal and abdominal muscles
127
Caution with what pt populations should be taken before giving neuraxial anesthesia?
COPD, Pickwickian syndrome (morbid obesity)(
128
What pulmonary effect is normal following neuraxial anesthesia?
Feelings of dyspnea; due to loss of sensory feedback in chest area
129
Apnea can occur following neuraxial anesthesia due to
Reduced blood flow to the brainstem
130
Afferent signals in the parasympathetic innervation of the GI system do what
Send sensory input from the GI system towards the CNS
131
Efferent signals in the parasympathetic innervation of the GI system do what
Send commands from the CNS to the GI system
132
Sympathetic innervation of GI system stems from _____
T5-L2
133
Sympathetic afferent GI signals transmit _____ pain
Visceral
134
Sympathetic efferent GI signals inhibit ____ and ___ which causes spinchter ______ and vasoconstriciton
Peristalsis
Gastric secretion
Contraction
135
Local anesthetics in neuraxial blocks decrease the activity of _______ nerves
Sympathetic
136
Neuraxial anesthesia increases ______ activity
Parasympathetic
137
Because vagal tone is unopposed in the GI system following neuraxial anesthesia, ___ % will incur nausea and vomitting
20%
138
Because neuraxial anesthesia increases parasympathetic activity in the gi system, it reduces the incidence of what following abdominal surgery
Ileus
139
Neuraxial anesthesia in combination with opioids causes _____ rentenion
Urinary
140
Blockade above T10 causes urinary sphincter tone to be ____ and leads to urination
relaxed
141
Which class of local anesthetics produces PABA as a metabolite
Esters
142
Which class of local anesthetics produce methylparaben as a metabolite
Amides
143
Is there cross sensitivity in esters?
Yes
144
Is there cross sensitivity between esters and amides?
No
145
What determines onset of action in LA
pKa
146
What determines potency in LA
Lipid solubility
147
What determines duration of action in LA
Protein binding
148
An isobaric solution has a baracity of
1
149
An hyperbaric solution has a baracity
greater than 1
150
Hypobaric solution has a baracity
Less than 1
151
What is the hyperbaric solution for Bupivicane
.75% in 8.25% dextrose
152
What is the hyperbaric solution for Lidocaine
5% in 7.5% dextrose
153
What is the hyperbaric solution for Tetracaine
0.5% in 5% dextrose
154
What is the hyperbaric solution for Procaine
10% in water
155
What are the isobaric solutions of Bupivicane
0.5% is saline
0.75% in saline
156
What is the isobaric solution of Lidocaine
2% in saline
157
What is the Isobaric solution of Tetracaine
0.5% in saline
158
What is the hypobaric solution for Bupivicane
0.3% in water
159
What is the hypobaric solution for Lidocaine
0.5% in water
160
What is the hypobaric solution for Tetracaine
0.2% in water
161
Regarding low and high points of the spinal vertebra, what are the highest levels when supine
C3 & L3 (Apex)
162
What are the lowest points in the spinal vertebra when supine
T6 & S2 (Trough)
163
Does metabolism of LA occur in the CSF?
NO
164
How are LA eliminated from the CSF?
By reuptake
165
What is the correct concentration for a a spinal dose with Bupivicane
0.5-0.75%
166
What is the typical DOSE of a spinal with Bupivicane that reaches T10
10-15mg
167
What is the correct DOSE of a spinal with Bupivicane that reaches T4
12-20mg
168
What is the onset of Bupivicane spinal
4-8 minutes
169
What is the duration of Bupivicane spinal
130-220 minutes
170
If you give epi with Bupivicane, how dose it effect the duration of action
+ 20 - 50%
171
What is the correct concentration of Levobupivicane in a spinal
0.5%
172
What is the correct DOSE of levobupivicane that reaches T10
10-15mg
173
What is the correct dosage of Levobupivicane that reaches T4
12-20mg
174
What is the onset of Levobupivicane
4-8 minutes
175
What is the duration of Levobupivicane in a spinal
140-230 minutes
176
What is the concentration of Ropivacaine in a spinal
0.5%- 1%
177
What is the correct dosage of Ropivacaine in a spinal that reaches T10
12-18mg
178
What is the correct dosage of Ropivacaine in a spinal that reaches T4
18-25mg
179
Onset of Ropivacaine in a spinal
3-8 minutes
180
Duration of Ropivacaine in a spinal
80-210 minutes
181
What is the correct concentration of 2-Chloroprocaine in a spinal
3%
182
What is the correct dose that reaches T10 in a spinal for 2-Chloroprocaine
30 - 40 mg
183
What is the correct dose in a spinal for 2-Chloroprocaine that reaches T4
40-60 mg
184
Onset of 2- Chloroprocaine in a spinal
2-4 minutes
185
Duration of 2-chloroprocaine in a spinal
40-90 minutes
186
What is the concentration of Tetracaine in a spinal
0.5 - 1%
187
Correct dose for T10 coverage with Tetracaine in a spinal
6-10 mg
188
Correct dose of Tetracaine for T4 coverage in a spinal
12-16mg
189
Onset of Tetracaine in a spinal
3-5 minutes
190
Duration of tetracaine in a spinal
90-120 minutes
191
How dose the addition of epi effect the duration of tetracaine in spinal
+20-50%
192
When administering an epidural, what incremental volume should be used to avoid unwanted effects
5 mL
193
What is the onset of a typical epidural
10-25 minutes
194
2-Chloroprocaine in epidural anesthesia comes in what two concentrations
2% and 3%
195
Which concentration of 2-chloroprocaine is used for Surgical anesthesia in epidurals
3%
196
What should a top off dose of a LA be when providing an epidural?
50-75% if inital dose
197
What is the timing of the top off dose?
Before the block decreases more than 2 dermatomes
198
What is the onset of 2 chloroprocaine for an epidural?
5-15 minutes
199
what is the duration of 2-Chloroprocaine in an epidural
30-90 minutes
200
What is the concentration of Lidocaine in an epidural
2%
201
What is onset of Lidocaine in an epidural?
10-20 minutes
202
What is the duration of lidocaine in an epidural?
60- 120 minutes
203
What is the concentration of Ropivacaine in an epidural?
0.1-0.75%
204
What is the onset of Ropivacaine in an epidural
15-20 minutes
205
What is the duration of Ropivacaine in an epidural
140- 220 minutes
206
What is the concentration of Bupivicane an epidural?
0.0625%-0.5%
207
what is the onset of Bupivacaine in an epidural
15-20 minutes
208
what is the duration of Bupivacaine in an epidural
160-220 minutes
209
What is the concentraition of Levobupivacaine in an epidural
0.0625% - 0.5%
210
Onset of Levobupivacaine in epidural
15-20 minutes
211
Duration of Levobupivacaine in epidural
150-225 minutes
212
In surgical anesthesia, what concentration is used for both Bupivacaine and Levobupivacaine
0.5%
213
In surgical anesthesia, what concentration of Ropivacaine is used
0.75%
214
Is the epidural concentration for Lidocaine and 2-Chloroprocaine the same as when used for surgical anesthesia?
YES
Lidocaine-2%
2-Chloroprocaine-3%
215
Why do we give neuraxial adjuncts?
Provides analgesia
Extends duration
Improves density of block
216
Do opioid adjuncts extend the duration of action of a epidural?
NO extension; ONLY analgesia and density of block
217
What are the opioids for epidural adjuncts that increase analgesia/density of the block?
Sufentanil, Fentanyl, Morphine
218
What two Alpha 2 agonist improve density, duration, and analgesia of neuraxial anesthesia
Dexmedetomidine, Clonidine
219
Can dexmedetomidine (Precedex) be given intrathecally?
YES
220
Why are vasopressors used as adjuncts in neuraxial anesthesia?
EXTENDS DURATION OF ACTION
221
What part of the spinal cord do neuraxial opoids target?
Dorsal Horn
222
What part of the dorsal horn do neuraxial opioids act on?
Lamina 2: Substantia gelatinosa
223
How do opioids affect potassium to negate pain signals?
Increase potassium conductance; Hyperpolarzizes the membrane
224
Which three neuraxial opioids are considered Hydrophilic
Morphine,
Hydromorphone,
Meperidine
225
What two neuraxial opioids are considered Lipophilic
Fentanyl
Sufentanil
226
Do hydrophilic or Lipophilic opoids stay longer in the CSF
Hydrophilic
227
How long do Hydrophilic neuraxial opioids take to start working
30-60 minutes
228
How long do Lipophilic neuraxial opioids take to start working
5-10 minutes
229
What is the intrathecal dose of SUFENTANIL
5-10 mcg
230
What is the epidural dose of SUFENTANIL
25-50 mcg
231
What is the epidural infusion dose of Sufentanil
10-20mcg/hr
232
What is the intrathecal dose for FENTANYL
10-20mcg
233
What is the epidural dose of FENTANYL
50-100 mcg
234
What is the epidural infusion dose of Fentanyl
25-100 mcg/hr
235
What is the epidural dose of Hydromorphone
0.5- 1mg
236
What is the epidural infusion dose of Hydromorphone
0.1-0.2 mg/hr
237
What is the intrathecal dose of MEPERIDINE
10 mg
238
What is the epidural dose of MEPERIDINE
25-50 mg
239
What is the epidural infusion dose of MEPERIDINE
10-60 mg/hr
240
What is the intrathecal dose of MORPHINE
0.25-0.30 mg
241
What is the epidural dose of MORPHINE
2-5 mg
242
What is the epidural infusion dose of Morphine
0.1 - 1mg/hr
243
What is a common problem following neuraxial adjunct with opoids
Pruritis
244
What are the prophylactic measures to prevent pruritis from neuraxial adjuncts
Minimize dose of morphine <300mcg
Ondansetron 4mg
Nubain 2.5-5.0 mg
245
What are the three treatments for Pruitis and neuraxial anesthesia
Benadryl 25-50mg
Naloxone 0.1mg
Buprenex
246
Which neuraxial adjunct leads to more respiratory depression than others
Morphine
247
Does intrathecal morphine require apnea monitoring IE: Capnography, pulse ox, alarms?
YES
248
What dose of naloxone reverses respiratory depression from morphine
0.1- 0.2 mg
249
Using morphine with a combination of Sufentanil or Fentanyl for neuraxial adjunct leads to a high incidence of what
Urinary retention & Nausea
250
What percent of people experience urinary retention and nausea following morphine in combination with Fent or sufentanil
30-40%
251
Clonidine and Precedex prolong neuraxial blockade by how long
Apron 1 hour
252
What is the "epi wash" dose
0.2-0.3 mg
253
When epi is added with what local anesthetic for neuraxial anesthesia is the block increased PROFOUNDLY
Tetracaine
254
If a pt develops a epidural hematoma from neuraxial anesthesia, within what time frame should surgical decompression occur
within 8 hours
255
Cox inhibitors inhibit cyclooxygenase which prevents the formation of what
thromboxane-A2
256
For high risk and intermediate surgical risk procedures, when do you hold aspirin
4-6 days prior
257
If a pt is undergoing a high risk procedure and taking NSAIDS at home, how long should they be held for
5-half-lives
258
Glycoprotein IIB/IIIA receptor antagonist work by
inhibiting fibrinogen binding to the IIB/IIIA complex
259
What is the regional anesthesia consideration reguarding glycoprotein IIB/IIA antagonist
Hold Tirofiban (Aggrastat) and Eptifibatide (Integrillin) for 4-8 hours before neuraxial anesthesia
260
What is the regional anesthesia consideration reguarding glycoprotein IIB/IIA antagonist
Hold abciximab (Reopro) for 24-48 hours before neuraxial anestheisa
261
How does heparin work?
Enhances the activity of antithrombin which inhibits thrombin(factor 2) and 9,10,11,12
262
Neuraxial consideration for low dose heparin <5,000 units
Hold for 4-6 hours prior
263
Neuraxial consideration for high dose heparin < or equal to 20,000 units
hold for 12 hours
264
Neuraxial consideration for therapeutic dose of heparin >20,000 units
hold 24 hours
265
If someone has had UFH for more than 4 days they should have what before a block
platelet count
266
How does low molecular weight heparin work
inhibits factor 10a or Xa
267
Neuraxial consideration for LMWH
If prophylactic dose delay for 12 hours, if therapeutic dose delay for 24 hours
268
Neuraxial consideration for Vitamin K antagonist
Hold for 5 days, ensure INR < 1.5
269
Thrombolytic agents such as TPA are ______ contraindications to neuraxial anesthesia
ABSOLUTE
270
Direct oral anticoagulants should be discontinued for ____ hours before neuraxial anesthesia
72 hours
271
Can you give neuraxial anesthesia if a pt is taking garlic, ginkgo, and ginseng?
If on no other blood thinning agents
272
What causes a Postdural puncture headache
Failure of the dura puncture site to properly seal over after needle breech
273
A PDPH can occur ___ days after puncture
2-3 days
274
Using what type of needle increases postdural puncture headache risk
cutting tip
275
What pt factors increase risk of PDPH
younger, female, pregnant
276
Can using loss of air for LOR increase risk for PDPH
YES
277
Which needle has the highest percentage of PDPH
Quincke
278
What are the two treatments for PDPH
Epidural Blood Patch
Sphenopalatine Ganglion Block (SPG block)
279
What other treatments are used for PDPH
Bed rest, caffeine, NSAIDS
280
CRNA's should wait how long before performing a blood patch?
48 hours
281
If paresthesia occurs when placing epidural or spinal, what should the CRNA do?
Redirection of needle immediately and documentation of the event
282
If spinal has not set up after 15 to 20 minutes what may be necessary?
Redo the block
283
If a patchy block occurs the CRNA should consider what to avoid neurtoxicty
IV sedation or general anesthesia
284
What is the common bacteria involved in post spinal bacterial meningitis
Streptoccous viridans
285
Chlorhexidine must be allowed to dry prior to the procedure to avoid
arachnoiditis
286
What nerves are affected in Cauda equina syndrome
L1-S4 + Coccygeal nerves
287
What percent liodcaine in SAB increases risk of cauda equina syndrome
5%
288
Treatment for Cauda Equina syndrome
Supportive care; laminectomy if disc compression or hematoma
289
Signs of transient neurological symptoms
Pain in the back and buttocks that spreads down both legs, pain usually starts within 6-36 hours after surgery
290
If the pt experiences a unilateral block, what can you do to troubleshoot the problem?
-Pull catheter back 1-2 cm slightly
-Reposition the pt on the opposite side not feeling numb
-Adminster diluted anesthetic to try and even out the block
291
If a pt retains catheter fragments what should the crna always do?
TELL THE PATIENT
292
If there is blood in the epidural needle, what can the CRNA do?
Adjust the needle to aim more midline
293
At what plasma cx of Lidocaine do pts experience Tinitus and circumoral numbness
5-10mcg/mL
294
At what plasma cx of lidocaine do pts experience Cardiovascular collapse
>25mcg/mL
295
What 3 things increase the risk of LAST
Hypercarbia
Hyperkalemia
Metabolic Acidosis
296
What three things decrease the risk of LAST
Hypocarbia
Hypokalemia
CNS depressants like benzos and barbituates
297
In what order of LA are most cardio toxic
Bupivacaine> Levobupivacaine> Ropivacaine> Lidocaine
298
First step in treatment of LAST
Give 100% oxygen
299
What drugs are given for seizures in LAST
Benzos!
AVOID PROPOFOL
300
CRNA's must take a modified approach to ACLS in LAST by doing what with EPINEPHRINE
Be cautious. Use less than 1mcg/kg
301
How should lipid emulsion therapy be given?
If pt over 70kg give 100mL bolus for 2-3 minutes followed by 250mL infusion over 15-20mins.
If pt under 70kg start with 1.5mL/kg bolus for 2-3 minutes followed by 0.25mL/kg/min infusion.
302
How long should you continue lipid infusion after stability has been regained
15 minutes
303
What is the maximum dose of lipid emulsion therapy for LAST
12mL/kg
304
What is the major symptom of Epidural/spinal hematoma
PAIN
305
What three things can lead to Arachnoiditis?
-Non approved admin of drug into intrathecal or epidural space
-Using non-preservative free solutions
-Betadine contamination
306
When doing neuraxial anesthesia, what should the CRNA be prepared to do also?
TO SWITCH TO GENERAL ANESTHESIA
307
What are three common reasons for neuraxial failure?
wrong dose
wrong location
wrong position
308
What are the two types of cutting needles used in spinals
-Quincke
- Pitkin
309
When using a pencil point needle in a spinal what can be sensed when puncturing the dura
a click or pop
310
What cx epi is given for epi test dose in an epidural?
1:200,000
(5mcg/mL)
311
Which epidural needle is least likely to puncture the subarachnoid space?
Tuohy
312
Which epidural needle is preferred when catheter placement is difficult
Crawford
313
Which epidural needle has "wings"
Weiss
314
How long is the epidural needle in length
9 cm
315
What is the optimal epidural space length/depth for the catheter
3-5 cm
316
When giving test dose of epi for epidural, how many CC do you give?
3 mL of 1.5% lidocaine with epi 1:200,000
317
What are symptoms of iv placement with epidural catheter
heart rate jump by 20% or more
Ringing in ears
Metallic taste
Numbness around mouth
318
If accidental spinal injection with epidural catheter occurs, what symptoms?
Dense motor block within 5 minutes of a test dose
319
For pregnant women what should you wait for when giving test dose?
After contraction is done
320
When giving initial dose of epidural, what should it be?
in increments of 5 mL, 1-2mL per segment to be anesthetized
321
If two segment regression has occurred, how much of a top off dose do you give?
1/2 or 3/4th of the intial dose
322
Recommended "top off" time from inital dose
Lidocaine - 60 minutes
2-Chloroprocaine- 45 minutes
Mepivacaine- 60 minutes
Bupivacaine and Ropivacaine - 120 minutes
323
Some patients are on heart medications (IE: Beta blockers) what symptom could also mean the needle is in a blood vessel during an epidural?
> 20 mmhg in blood pressure
324
If a pt is having a peri-anal/anal surgery and needs a saddle block, what dermatome needs to be blocked?
S2-S5
325
If a pt is having foot and ankle surgery, what dermatome would need to be blocked?
L2
326
If a pt is having thigh/lower leg/knee surgery what dermatome needs to blocked
L1
327
If a pt is having vaginal delievery/uterine/hip/turp procedure what level dermatome is desired?
T10
328
For a procedure of the Scrotum what desired level dermatome?
S3
329
For surgeries of the penis, what desired dermatome level
S2
330
For a testicular procedure what dermatome level?
T8
331
For a urologic/gynecologic/lower abdominal procedure what dermatome?
T6
332
What dermatome level for a Cesarean section/upper abdominal level
T4
