Considerations for Epidural & Spinal Anesthesia Flashcards

1
Q

What is an epidural anesthetic?

A

injection of a local anesthetic into the epidural
space for spread to the region of the dural cuffs

– Leaks into intravertebral foramen and paravertebral spaces
– Medication spread is diffusion dependent
– Onset is longer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the idea behind epidural/spinal anesthesia?

A

Reversible chemical blockade of neuronal transmission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What lasts longer, epidural or spinal?

A

epidural

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is interrupted with administration of an epidural or spinal?

A

autonomic, sensory and
motor nerve fiber transmission

[EPIDURAL} results are related to drug concentration & volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Results of an epidural is related to?

A

drug concentration & volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are 2 major differences between a spinal and epidural?

A
  1. Spinal directly bathes spinal cord in local anesthetic
  2. Epidural is titratable & can be redosed

[spinal catheter CAN be placed but it is RARE!]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are 2 other names for a spinal?

A
  1. subarachnoid block

2. intrathecal block

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are 6 advantages of an epidural?

A
  1. ↓ surgical stress
  2. ↓ opioid consumption
  3. ↓ overall blood loss
  4. ↓ risk of DVT
  5. provides anesthesia OR analgesia (can re-dose, or convert from pain to primary anesthetic in laboring mother)
  6. versatile
    - can use with or without adjunctive medications
    - can control extent of sensory or motor blockade based on concentration of local anesthetic used
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are 4 disadvantages of an epidural?

A
  1. post dural puncture headache (PDPH)
  2. sympathetic blockade occurs 100% of the time
  3. block may last longer than the procedure
  4. urinary retention
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is more difficult, an epidural or spinal?

A

epidural

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are considerations when deciding to do an epidural?

A
  1. length of surgery
  2. multimodal pain management
  3. procedure
    [involving abdomen, lower extremities]
  4. certain comorbidities
    [pulmonary disease; will keep the pt breathing, no GA necessary]
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are 5 absolute contraindications to an epidural?

A
  1. pt refusal
  2. increased ICP
  3. severe aortic or mitral valve stenosis
  4. severe hypovolemia
  5. infection at injection site
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are relative contraindications for an epidural?

7

A
1. Uncooperative patient
       • Inability to communicate / obtain informed consent
        • Unable to assist
2. Local anesthetic allergy
3. Patient on anticoagulant or thrombolytic therapy [why are they on it? afib, DVT?] --- this might be why doing an epidural is GOOD for them... 
4. Preexisting neurologic deficit
5. Chronic headache or backache
6.  Severe spinal deformity
7.  Valvular stenosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pre-procedure medications for epidural placement?

A
  1. anxiolytic, do not over sedate!
  2. follow NPO guidelines
  3. consider IV bolus if pt is dehydrated?
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Minimum pre-procedure monitoring for epidural placement?

A
  1. IV
  2. Suction
  3. Airway supplies
  4. ECG, BP, SpO2,
  5. oxygen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What should be available when performing an epidural?

A
  • suction
  • airway supplies
  • supportive medications [induction agent, paralytic, atropine, vasoactive meds, zofran]
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What type of regional anesthesia is high volume?

A

epidural

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 2 needle approaches for spinal/epidurals?

A
  1. midline

2. paramedian

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What vertebral body aligns with the lower scapula tip?

A

T7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What vertebral body aligns with the end of an adult spinal cord?

A

L1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What vertebral body aligns with superior iliac crests?

A

L4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What vertebral body aligns with the posterior superior iliac spines? (dimples)

A

S2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What movement of the spine will create larger interspinous spaces?

A

flexion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do you check right before performing an epidural?

A
  1. patent IV
  2. monitoring devices
  3. oxygen attached & functioning
  4. resuscitation equipment is available
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are characteristics of a Tuohy needle?

A
  • pronounced curve
  • easier for novice
  • directional placement of catheter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are characteristics of a crawford needle?

A
  • not curved
  • easier to insert
  • higher rate of dural puncture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How long is a standard epidural needle?

A

9cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are 2 factors that alter distance to the ligamentum flavum?

A
  1. body habitus

2. level of placement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the standard depth of the epidural space in the lumbar region?

A

5cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What type of needle requires an introducer?

A

spinal needle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How is the bevel situated when doing a spinal or epidural?

A

bevel “up” towards patient’s head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the needle advanced through when placing an epidural?

A
  1. skin
  2. SQ tissue
  3. supraspinous ligament
  4. interspinous ligament
  5. ligamentum flavum
  6. epidural space!
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How is the needle inserted/advanced when placing an epidural?

A

VERY SLOW!! mm BY mm!!

tap plunger of syringe between movements

TAP EVERY mm!!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

If using the “loss of resistance” technique for epidural placement, how much NS or air is in the syringe?

A

2-3mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are you waiting for when advancing an epidural needle?

A

loss of resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

How does an epidural catheter compare to the epidural needle?

A

the catheter is 2 gauge sizes smaller

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Dashed lines on an epidural catheter represent, what?

A

1cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Two dashed lines on an epidural catheter represent, what?

A

10cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Two thick lines on an epidural catheter represent, what?

A

12cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is the distance from the hub of the epidural needle to the tip?

A

12cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How far should the epidural catheter be left in the epidural space?

A

3-5cm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What can happen if the epidural catheter is left inserted too deep?

A
  1. puncture of the dura
  2. passage into epidural veins
  3. migration through intervertebral foramen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What must be remembered when manipulating the epidural catheter and needle?

A

NEVER attempt to withdrawal the catheter through the needle

-catheter can break & shear, leaving pieces in the patient!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

After placement of an epidural catheter, the needle is removed, then what?

A

attach adapter to free end, look for blood or CSF, gently aspirate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

After attaching the adapter to the epidural catheter, looking for blood or CSF, and gently aspirating, what next?

A

administer test dose

1.5% lidocaine with 1:200000 epi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What medication is used as the test dose for an epidural?

A
  1. 5% Lidocaine
    1: 200,000 epi

total: 3mL = 45mg lidocaine with 15mcg epi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

How will you know if the epidural is in place?

A

3mL test dose will cause profound spiral block

OR

HR/BP will ↑ more than 20% if the test dose is administered into the vasculature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What must be remembered before giving an epidural “test dose”?

A
  • ask patient, are you about to have/are having a contraction?
  • tell me if you hear ringing in your ears, taste metal, or feel your bottom get heavy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What will happen if your epidural test dose is administered as a spinal?

A

heavy SADDLE BLOCK within 30 seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

When is the paramedian epidural approach useful?

A

when the patient cannot flex their spine. [Hx spinal surgery, rheumatoid arthritis, hip or upper leg trauma]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Where is the skin wheal placed when performing a paramedian approach?

A

1cm lateral and 1cm caudal to spinous process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

When using a paramedian approach for epidural placement, what does the needle advance through?

A
  1. skin
  2. SQ
  3. paraspinous muscles
  4. ligamentum flavum

(does NOT pass through supraspinous or interspinous ligaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What do you do if a patient reports paresthesia?

A

stop moving, ask if it stops

if the paresthesia goes away, continue

if paresthesia does not stop, remove needle & catheter together and restart at interspinous space above

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

How do you redirect the epidural needle after hitting bone?

A

pull the needle and stylet back into SQ fat, reposition the introducer then reinsert the needle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What do you do if you get blood in the epidural needle?

A

withdrawal the needle & catheter and replace

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What are 3 indications of caudal anesthesia?

A
  1. hemorrhoidectomy
  2. chronic pain patients
  3. pediatric analgesia (inguinal herniorrhaphy, circumcision, perineal procedures)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

How is a patient positioned for a caudal block?

A
  1. prone on a flexed table or with a pillow under pelvis, legs spread and externally rotated
  2. laterally
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What is the dose of a caudal block?

A
  1. 5-1mL/kg
    - varying LA concentrations

2.5mg/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

When doing a caudal block, ensure you are not in which two spaces?

A

bone

subcutaneous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What is the volume for adult caudal sacral anesthesia?

A

12-15mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is the volume for adult caudal lower extremity block

A

20-30mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What are 3 complications of adult caudal anesthesia?

A
  1. high failure rate (false passage)
  2. inadvertent IV injection or catheter placement
  3. dural puncture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What are the two types of combined spinal epidural?

A
  1. 2 level; spinal placed then epidural catheter placed 1-2 levels above
  2. 1 level; placement of epidural needle, spinal needle is passed through & small intrathecal dose injected, then epidural catheter placed through epidural needle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What are concerns of combined spinal epidural in the partruient?

A
  1. intrathecal opioid effects on fetus
  2. inability to ambulate after receiving narcotics
  3. maternal hypotension & itching
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What are 6 potential complications of combined spinal epidural?

A
  1. failure to obtain either block
  2. catheter migration
  3. increased spinal level
  4. metallic particles
  5. PDPH
  6. neurologic injury
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What 2 things does neuraxial imaging facilitate in spinal/epidural placement?

A
  1. identify interspaces

2. determine depth to epidural space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

How much metabolism of local anesthetics occurs in the CSF?

A

little to no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What does added vasopressor do to local anesthetics?

A

slows absorption and prolongs block

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What are 3 ester local anesthetics?

A
  1. procaine
  2. Chloroprocaine
  3. Tetracaine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What are 4 amide local anesthetics?

A
  1. lidocaine
  2. mepivacaine
  3. ropivacaine
  4. bupivacaine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What is the onset & duration of procaine?

A

slow / 60-90m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What is the onset & duration of Chloroprocaine?

A

Fast 30-60m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What is the onset & duration of tetracaine?

A

slow / 180-600m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What is the onset and duration of lidocaine?

A

fast, 90-20m

75
Q

What is the onset & duration of mepivacaine?

A

fast 120-240m

76
Q

What is the onset & duration of ropivacaine?

A

slow / 180-600m

77
Q

What is the onset & duration of bupivacaine?

A

slow / 180-600m

78
Q

Density of the block is most affected by, what?

A

concentration of the local anesthetic

79
Q

Spread of a block is most affected by, what?

A

volume of the local anesthetic used

80
Q

No more than ___ amount per injection?

A

3-5mL

81
Q

Injection of neuraxial local anesthetic occurs after what?

A

aspiration attempt

82
Q

If the needle is placed caudal, how much volume is administered per segment to raise the level of the block?

A

2mL / segment

83
Q

If the needle is placed lumbar, how much volume is administered per segment to raise the level of the block?

A

1mL / segment,

non-pregnant, non-obese pts can go up to 2mL/segment

84
Q

If the needle is placed thoracic how much volume is administered per segment to raise the level of the block?

A

0.7mL / segment

85
Q

What type of medication is clonidine and why is it added to epidurals?

A

alpha 1 agonist

when mixed with lidocaine or bupivacaine, has synergistic effects for labor analgesia

86
Q

When using opioids in a spinal or epidural, what kind need to be use?

A

PRESERVATIVE FREE

87
Q

What are the two most commonly used opioids in spinal/epidurals?

A

fentanyl

morhpine

88
Q

What is the dose of Fentanyl in epidural anesthesia?

A

50-100mcg

89
Q

What is the onset of Fentanyl in spinal/epidural anesthetics?

A

10-15m

90
Q

What is the duration of Fentanyl in spinal/epidural anesthesia?

A

1-2H

91
Q

What is the dose of morphine in epidural anesthesia?

A

2-4mg

92
Q

Is morphine polar or non-polar?

A

polar

93
Q

Is morphine lipid soluble?

A

not very

94
Q

What are 2 adverse effects of using morphine in spinal/epidural anesthetics?

A
  1. itching

2. urinary retention

95
Q

The goal of neuraxial anesthesia is to block what?

A

Adelta & C fibers

96
Q

What type of nerve fibers are blocked first?

A

Type B; preganglionic autonomic vasomotor

97
Q

What are Adelta fibers?

A

pain, cold temperature, touch

heavy meylination
intermediate block onset

98
Q

What are C fibers?

A

pain, warm and cold temperature, touch

no myelination
early block onset

99
Q

At what level are cardiac accelerator fibers?

A

T4

100
Q

What is the first sign a local anesthetic block is working?

A

flushing/hypotension

101
Q

What mirrors sensory loss?

A

temperature discrimination

102
Q

How often should dermatome level of block be checked?

A

every 2-3 minutes

103
Q

Autonomic blockade is usually where compared to sensory?

A

two dermatome levels higher

104
Q

Upper limit of MOTOR block is usually where compared to sensory block?

A

two levels BELOW sensory block

105
Q

Two risk factors for PDPH?

A
  1. needle size & type

2. young, female, pregnant

106
Q

PDPH in the first 24 hours?

A

conservative

  • recumbent position
  • analgesics
  • fluid administration
  • caffeine
  • stool softeners & soft diet
107
Q

What is an epidural blood patch?

A
  • access epidural space
  • someone else sterile obtains 15-20mL of blood
  • infuse 15-20mL of blood into epidural space BELOW initial puncture site
108
Q

No more than how much LA is injecting during spinal?

A

2mL

109
Q

To anesthetize motor & sensory, local anesthetic concentration should be?

A

0.5% or higher

110
Q

What is the specific gravity of CSF?

A

1.003 - 1.009

111
Q

What additive is used to make a hyperbaric spinal local anesthetic?

A

dextrose

112
Q

What additive is used to make a hypobaric spinal local anesthetic?

A

water

113
Q

What should you call bone when you hit it with the needle?

A

Oss

114
Q

What should you call blood if you see it during a spinal or epidural?

A

Heme

115
Q

If 2 intervertebral spaces look “good”, which one should you use first?

A

the lower then move up if you need to

116
Q

What is the swirl between NS and hyperbaric local anesthetic called?

A

biferengence

117
Q

What is rechecking aspiration called?

A

barbitage

118
Q

If a patient tells you they can’t breathe after placement of a spinal or epidural, what should you have them do?

A

squeeze your hand and let go

119
Q

At what anatomical location does a spinal block occur?

A

ventral and dorsal nerve roots

120
Q

What can be controlled when using a spinal block?

A

block distribution

121
Q

What are 4 indications of using a spinal block?

A
  1. full stomach (↓ aspiration risk compared to general)
  2. difficult airway (keeps them awake & breathing)
  3. minimal metabolic impact (liver dz, kidney dz, diabetes)
  4. reduction in systemic BP leads to ↓ risk of DVT & ↓ risk of blood loss
122
Q

What is a normal aortic cross sectional area?

A

2 cm^2

123
Q

What is CSA of mild aortic valve stenosis?

A

> 1.5 cm^2

124
Q

What is CSA of severe aortic valve stenosis?

A

<1 cm^2

125
Q

What vital sign needs to be considered when choosing to do neuraxial block?

A

Blood pressure…

severe chronic HTN will not tolerate the generalized vasodilation

126
Q

What is the most prominent cervical process?

A

C7

127
Q

What vertebral body lies at the inferior tip of the scapula?

A

T7

128
Q

What factors influence the local anesthetic level of a spinal block?

A
  1. baricity of the local anesthetic used
  2. position of the patient
  3. drug dose
  4. site of injection

also..
[patient’s height, pregnancy, age, CSF volume, curvature of the spine, drug volume, intra-abdominal pressure, needle direction]

129
Q

What is the most dependent area of the supine spine?

A

T4-T8

130
Q

How is a 25G or smaller spinal needle used?

A
  1. place introducer midline in lower third of the interspace

(where lidocaine wheal should have been placed)

  1. then pass spinal needle through introducer
  2. advance through 2 ligaments (which are?)
  • supraspinous
  • interspinous
  1. you may feel 2 “pops”
    - ligamentum flavum
    - dura
131
Q

How slow should local anesthetic be injected into the spinal canal?

A

doesn’t matter

132
Q

How should local anesthetic be injected into the spinal canal?

A
  1. aspirate gently (make sure you get CSF)
  2. administer 50% of medication
  3. aspirate gently again
  4. administer 2nd half of medication
133
Q

If a bilateral spinal block is desired, how should the patient be placed immediately after medication administration?

A

supine with head slightly elevated

134
Q

If a unilateral block is desired, how should the patient be positioned immediately after medication administration?

A

leave the patient in the lateral position for at least 3 minutes prior to returning supine, slightly elevate the patient’s HOB

135
Q

What are the 2 “types” of spinal needles?

A

cutting vs pencil point

136
Q

What should you do if you are using a pencil needle and feel the dural “pop” but do not get CSF?

A

ensure stylet is in needle, advance spinal needle by 1-2mm and/or spin needle

[bevel might be covered or not fully inside the dura]

137
Q

What is one benefit of using a pencil spinal needle vs a cutting spinal needle?

A

less reports of PDPH

138
Q

What should you do if you get blood when performing a spinal block?

A
  1. frank blood = pull all equipment out and start over

2. blood or pink tinged CSF. Allow CSF to flow for several seconds to see if it clears

139
Q

What do you do if the spinal needle is FAR in and you hit bone?

A

traversed dura? possibly

  1. remove stylet
  2. attach syringe to needle
  3. slowly remove needle while gently aspirating

*pt is at increased risk for PDPH

140
Q

What type of nerve block is rapid?

A

B fiber, will cause hypotension

141
Q

What sensation mirrors sensory loss?

A

temperature discrimination

142
Q

In a good sensory block, a patient is unable to discriminate what 2 sensations?

A
  1. light touch

2. temperature

143
Q

Blocking which nerve fibers leads to surgical muscle relaxation?

A

Aalpha
Abeta
Agamma

144
Q

If A alpha, beta, & gamma fibers are blocked what may the patient still feel?

A

pressure

145
Q

How often should vital signs be checked when a patient has a spinal block?

A

2-3 minutes

146
Q

What should be checked along with vital signs every 2-3 minutes when a patient has a spinal block?

A

assess the level/degree of block.

use alcohol pad = cold

147
Q

What is the easiest way to adjust the level of a patient’s spinal or epidural block?

A

reposition/change their position

148
Q

Autonomic blockade relates to sensory blockade, how?

A

autonomic block is usually 2 levels HIGHER than sensory

149
Q

Motor blockade relates to sensory blockade, how?

A

motor block is usually 2 levels LOWER than sensory

150
Q

At what location does a saddle block occur?

A

S2-S5

** little autonomic effect

151
Q

At what level does a “low spinal” block occur?

A

T10

**blocks lumbar and sacral nerve roots

152
Q

What is the most common level for a spinal block?

A

T4

153
Q

What procedures can be done with a spinal block at T4?

A

abdominal and lower extremity procedures

154
Q

What procedures can be done with a spinal block at T10?

A

low abdominal & lower extremity vascular & ortho procedures

155
Q

At what level does a “high spinal” block occur?

A

C8

156
Q

What is the onset of morphine when used in an epidural?

A

10-15 minutes

157
Q

What is the duration of action of morphine when used in an epidural?

A

8-10 hours

158
Q

What is the lumbosacral “Taylor” approach for a spinal block?

A

modified paramedian approach

uses L5-S1 interspace

159
Q

How is the “Taylor” lumbosacral approach completed?

A
  1. identify posterior superior iliac spine
  2. make skin wheal 1cm medial and 1mc caudal to the spine
  3. insert needle at 45-55d angle medial and cephalad to the dorsal surface of the sacrum toward the midline of the lumbosacral foramen
160
Q

What size epidural needle is used for placement of a SPINAL catheter?

A

17G

161
Q

How is medication given through a SPINAL catheter?

A

small, slow doses

slow onset of hypotension

162
Q

What is one situation in which a spinal catheter could be placed?

A

if a “wet tap” occurs when attempting placement of an epidural catheter

163
Q

What are 3 additive medications to a spinal block?

A
  1. epinephrine
  2. phenylephrine
  3. clonidine
164
Q

What is the dose of epinephrine in a spinal or epidural?

A

0.1 - 0.2 mL of 1:1000 = 100-200mcg of epinephrine

165
Q

Epinephrine has the greatest effect when added to what local anesthetic?

A

tetracaine

166
Q

How much phenylephrine is added to local anesthetic?

A

0.05-0.2mL of 1% phenylephrine

^^
10mg/mL = 0.5-2mg of phenylephrine

167
Q

Phenylephrine has the greatest effect when added to what local anesthetic?

A

tetracaine

168
Q

Is clonidine a vasoconstrictor?

A

no

169
Q

What is the MOA of clonidine?

A

selective alpha 2 agonist

170
Q

When is clonidine used in local anesthetics?

A

when epinephrine is contraindicated

171
Q

Clonidine has synergistic effects with what local anesthetics?

A

lidocaine

bupivacaine

172
Q

The central action of clonidine helps with what?

A

tourniquet pain

173
Q

What are 2 benefits of Fentanyl’s high lipid solubility when used in spinal/epidurals?

A
  1. binds directly to lipid elements of the spinal cord

2. less drug available to diffuse systemically

174
Q

When administered in a spinal anesthetic, when will morphine reach the respiratory center?

A

6-8 hours

175
Q

How does morphine act in the spinal column?

A

drifts freely in the CSF

176
Q

What is the dose of Fentanyl in spinal anesthesia?

A

12.5-25mcg mixed with local anesthetic

177
Q

What is the onset of Fentanyl in spinal anesthesia?

A

5-10 minutes

178
Q

What is the duration of action of Fentanyl in spinal anesthesia?

A

2-4H

179
Q

What is the dose of morphine in spinal anesthesia?

A

0.1-0.25mg mixed with local anesthetic

180
Q

What is the onset of morphine when used in spinal anesthesia?

A

60-90 minutes

181
Q

What is the duration of action of morphine when used in spinal anesthesia?

A

~24 hours

182
Q

What is one adverse effect of morphine that is specific to SPINAL anesthesia?

A

DELAYED RESPIRATORY DEPRESSION

183
Q

What are some complications of spinal anesthesia?

A
  • hypotension
  • intercostal muscle paralysis
  • apnea/phrenic nerve paralysis
  • paresthesia
  • subarachnoid or epidural hematoma
  • meningitis/epidural abcess
  • chemical meningitis
  • cauda equina syndrome
  • transient neurologic symptoms
  • new nervous system lesion
  • exacerbation of preexisting neurologic disease
  • N/V
  • urinary retention
  • PDPH