Obstetrics 2

Question 1

All of the following are appropriate for pain relief during the first stages of labor EXCEPT a/an:
a. paracervical block
b. pudendal block
c. paravertebral sympathetic lumbar block
d. epidural block

Answer 1

b. pudendal block
the first stage of labor should seek to anesthetize T10-L1; Pudendal nerve derives from S2-S4- this would be more appropriate during the second stage

Question 2

The first stage of labor pain originates from

Answer 2

T10-L1

Question 3

The second stage of labor pain originates from

Answer 3

T10-S4

Question 4

Analgesic options that target the first stage of labor pain includes

Answer 4

neuraxial blockade, paravertebral lumbar sympathetic block, and paracervical block

Question 5

Analgesic options that target the second stage of labor pain include

Answer 5

neuraxial blockade and pudendal nerve block

Question 6

______________ has made a resurgence as a non-invasive alternative for labor analgesia

Answer 6

Inhaled nitrous oxide

Question 7

The ______ technique provides the dual benefit of a rapid onset of spinal anesthesia and the ability to prolong the duration of anesthesia with an indwelling epidural catheter

Answer 7

CSE

Question 8

Pin in the first stage of labor begins in the

Answer 8

lower uterine segment and the cervix

Question 9

The second stage of labor adds in pain impulses from the

Answer 9

vagina, perineum, and pelvic floor

Question 10

Describe the quality of perineum pain in the second stage of labor.

Answer 10

sharp, well-localized

Question 11

Describe the afferent pathway of perineum pain.

Answer 11

pudendal nerve

Question 12

Describe the afferent pathway of the uterus and cervix.

Answer 12

visceral C fibers hypogastric plexus

Question 13

Describe the quality of pain originating form the uterus and cervix.

Answer 13

Dull
diffuse
cramping

Question 14

Describe two consequences of uncontrolled pain.

Answer 14

increased maternal catecholamines
maternal hyperventilation

Question 15

What is the downslope effect of increased maternal catecholamines?

Answer 15

Hypertension and reduced uterine blood flow

Question 16

What is the downslope effect of maternal hyperventilation?

Answer 16

leftward shift of oxyhemoglobin curve–> reduced delivery of oxygen to the fetus

Question 17

How does a 50/50 N2O + O2 mixture affect uterine contractility?

Answer 17

it does not impair uterine contractility

Question 18

What is the epidural extension technique?

Answer 18

Injection of saline into the epidural space immediately after the local anesthetic is administered into the subarachnoid space; allows for rostral spread of local anesthetic

Question 19

Which local anesthetic reduces the efficacy of epidural morphine?
a. etidocaine
b. ropivacaine
c. levobupivacaine
d. 2-chloroprocaine

Answer 19

d.- 2- chloroprocaine antagonizes mu and kappa receptors in the spinal cord; this reduces the efficacy of epidural morphine
No other local anesthetics do this

Question 20

Common local anesthetics used in obstetrics include

Answer 20

bupivacaine
ropivacaine
lidocaine
2-chloroprocaine

Question 21

_________ is contraindicated via epidural due to the risk of toxicity with IV injection.

Answer 21

0.75% bupivacaine

Question 22

Compared to bupivacaine, _______ has a lower risk of CV toxicity.

Answer 22

ropivacaine

Question 23

When administered alone, neuraxial opioids confer the following benefits:

Answer 23

• no loss of sensation or proprioception
  -no sympathectomy (i.e. superior hemodynamic stability)
  -they do not impair mom’s ability to push

Question 24

Meperidine has ______ properties

Answer 24

local anesthetic

Question 25

Side effects of neuraxial opioids include

Answer 25

pruritus (most common) N/V sedation respiratory depression they do not meaningfully depress the fetus

Question 26

Which local anesthetics that are used for neuraxial technique have a long duration?

Answer 26

bupivacaine ropivacaine levobupivacaine

Question 27

Which local anesthetics that are used for neuraxial technique have an intermediate duration of action?

Answer 27

lidocaine

Question 28

Which local anesthetics that are used for neuraxial technique have a short duration of action?

Answer 28

2-chloroprocaine

Question 29

Which local anesthetic is not popular for labor analgesia due to strong motor block (which makes it good for C-section)?

Answer 29

lidocaine risk of neurotoxicity if given in the SAH

Question 30

Levobupivacaine has ________ compared to bupivacaine but is

Answer 30

less CV toxicity but is not available in the US

Question 31

Ropivacaine when compared to bupivacaine has

Answer 31

less risk of CV toxicity less potency less motor block

Question 32

This medication is useful for emergency C-section when epidural is already in place due to its very fast onset

Answer 32

2-chloroprocaine

Question 33

2-chloroprocaine has a risk of ______ when used for spinal anesthesia due to preservatives

Answer 33

arachnoiditis

Question 34

2-chloroprocaine solutions without ______ and ________ do not cause neurotoxicity

Answer 34

methylparaben and metabisulfite

Question 35

Bupivacaine has _____ placental transfer

Answer 35

low placental transfer due to increased protein binding and ionization

Question 36

Bupivacaine has _____ sensory block relative to other LAs

Answer 36

greater

Question 37

Cardiac toxicity with bupivacaine is more common with

Answer 37

R-enantiomer

Question 38

______ occurs before seizures

Answer 38

cardiac toxicity

Question 39

Lidocaine is not typically used for continuous infusion because _______ is more likely to develop, and it crosses the placenta to a greater degree than the alternatives.

Answer 39

tachyphylaxis

Question 40

What is the spinal bolus for bupivacaine?

Answer 40

1.25-2.5 mg

Question 41

What is the spinal bolus for ropivacaine?

Answer 41

2-3.5 mg

Question 42

What is the spinal bolus for levobupivacaine?

Answer 42

2-3.5 mg

Question 43

What is the epidural bolus for bupivacaine?

Answer 43

0.0625-0.125%

Question 44

What is the epidural bolus for ropivacaine?

Answer 44

0.08-0.2%

Question 45

What is the epidural bolus for levobupivacaine?

Answer 45

0.0625-0.125% (same as for bupivacaine!)

Question 46

What is the epidural bolus dose for lidocaine?

Answer 46

0.75-1%

Question 47

The loading volume for an epidural bolus is

Answer 47

10-15 mL in divided doses

Question 48

What is the epidural continuous infusion rate for both bupivacaine and levobupivacaine?

Answer 48

0.05-0.125%

Question 49

What is the epidural continuous infusion for ropivacaine?

Answer 49

0.08-0.2%

Question 50

What is the epidural continuous infusion for lidocaine?

Answer 50

0.5-1%

Question 51

What is the lumbar infusion rate for continuous epidural infusion?

Answer 51

8-15 mL/hr.

Question 52

Describe the spinal bolus, epidural bolus, and epidural continuous infusion for fentanyl?

Answer 52

spinal: 15-25 mcg Epidural: 50-100 mcg Epidural continuous: 1.5-3mcg/mL

Question 53

Describe the spinal bolus, epidural bolus, and epidural continuous infusion for morphine.

Answer 53

spinal: 125-250 mcg epidural: NA Epidural continuous: NA