Neuraxial Anesthesia

Question 1

History of the spinal

___64 - Cerebral spinal fluid was first
identified by Cotugno
18__ - Corning was the first documented
individual to inject into the intraspinous space
18__ - Quincke used spinal needles to
relieve elevated ICP in patients with
tubercular meningitis

Answer 1

1764

1885

1891

Question 2

Cervical and thoracic spinals are less popular because:

Answer 2

accidentally injecting into the spinal cord, a syrinx can form that will grow and grow until it leads to death

Question 3

Entire gut arises embryologically from what dermatome and indicates the entire abdomen is anesthetized?

Answer 3

T10

Question 4

Where do you block during labor? There are 2 stages and two dermatome ranges.

Answer 4

1st stage: T8-T10 for uterus contraction

2nd stage: T10-L1, L3 during delivery

Question 5

What dermatome innervates kidneys and uterus?

Answer 5

T10

Question 6

What dermatomes innervate the vaginal introitis?

Answer 6

S2-S3

Question 7

What dermatome innervates the anus?

Answer 7

S4

Question 8

Sensory pathways can ascend as much as two levels higher. In other words, Uterine pain can be felt as high as T8. True or false?

Answer 8

True

Question 9

Things that you can alter in an epidural: (5)

Answer 9

location of needle–center of LA action

infusion rate

drug

concentration

other adjuncts

Question 10

A L5/S1 epidural requires a rate of ____
cc/hr to achieve a T10 block

Answer 10

14+

Question 11

A T10 epidural requires a rate of ___ cc/hr to
provide adequate labor analgesia

Answer 11

4

Question 12

The rate of infusion is equal to the _____ of your anesthetic.

Answer 12

Rate = Distribution
Rate = Distribution
Rate = Distribution

Question 13

What are the signs of systemic toxicity? (3)

Answer 13

ringing in ears

funny taste in the mouth

numbness around the mouth

Question 14

What LA has a fast onset?

Answer 14

chloroprocaine

Question 15

What LA has intermediate onset?

Answer 15

lidocaine

Question 16

What LA has a slow onset?

Answer 16

bupivicaine (4-6 minutes)

Question 17

Nerves affected in what order?

Answer 17

Sympathetics first

sensory

motor

Question 18

What is a downside to using chloroprocaine? (2)

Answer 18

tachyphlaxis

interferes with opioid effectiveness

Not recommended for surgergy > 1 hour

Question 19

Procaine onset?

Duration?

Answer 19

3 minutes

30-40 minutes

Question 20

Lidocaine onset?

Duration?

Problems?

Answer 20

4-5 minutes

45-60 minutes

tachyphlaxis

Question 21

The lower the pKA, how is the onset affected?

Answer 21

faster onset

Question 22

_____ affects what you feel and wheter you retain motor function.

Answer 22

Concentration

Thus adjust concentration not rate when making adjustments!

Question 23

How does epinepherine increase effectiveness of local? (2)

Answer 23

decreased uptake

increased duration

Question 24

What are several adjucts to LA to lower concentration of anesthetic administered? (3)

Answer 24

epi

clonidine

opioid like Duramor, is a preservative-free one

Question 25

How do we prepare for an epidural? (3)

Answer 25

get consent give lots of fluids to prevent hypotension, prefer coload get position

Question 26

Goal of epidural for labor and delivery rate:

Answer 26

T8 - L3, min 14+ cc/hr

Question 27

What approach do we prefer for elderly pts?

Answer 27

paramedian because of calcified supraspinous ligament

Question 28

What position is better during an emergency?

Answer 28

lateral decubitus because pt can't fall and fetus will not be distressed if pregnant patient

Question 29

What position is technically more difficult?

Answer 29

lateral decubitus

Question 30

Where do we want to place a spinal needle?

Answer 30

around L2

Question 31

Preload is the act of administering a bolus of \_\_\_-\_\_\_ L immediately prior to placing a neuraxial block. Coload is the administration of \_\_\_-\_\_\_ L fluid as a block is in the process of setting up

Answer 31

1-2

Question 32

Air vs. Normal Saline Downside of ___ : it can track around nerve roots and prevent exposure to local anesthetics

Answer 32

air

Question 33

What is the test dose of lidocaine and epinepherine?

Answer 33

45 mg at 1.5% lidocaine and 15mcg of epi at 1/200,000

Question 34

How much should we thread the catheter?

Answer 34

3-5 cm is ideal

Question 35

What do you look for in the test dose to indicate that you are in the right epidural space?

Answer 35

tachycardia HTN perioral numbness hearing changes metallic taste profound numbness

Question 36

What are some troubleshooting issues? (4)

Answer 36

inadequate analgesia: no block, one-sided, patchy, or wears off too quickly puritis hypotension too dense

Question 37

What should you document when removing epidural catheter?

Answer 37

blue tip intact

Question 38

What if you determine there is no block? What do you do?

Answer 38

start over

Question 39

If patient complains that they are only feeling it on one side. What may have happened? (2) What do you do?

Answer 39

Catheter may be in too far, or pt was lying on the side for too long Septated epidural space Replace it

Question 40

What may have occurred in a patchy block? What is it called?

Answer 40

a window It can be caused by air around the nerve root. It is also possible that a certain nerve may be repeatedly stimulated.

Question 41

How do you treat a patchy block? (4)

Answer 41

volume bolus withdraw the catheter 1-2 cm lie the patient "window" side down small bolus of higher concentration LA vs. opioid bolus

Question 42

The patient appears to have a complete motor block of the left leg but not the right. There is a sensory block T10 bilaterally. The left side has no sensory block above T10. Horner’s Syndrome has appeared on the right.

Answer 42

Remove and start over numb skull! Give ventilatory support!

Question 43

Block that “wears off” What is the solution? (2)

Answer 43

* You forgot to start the infusion * The infusion isn’t connected/set up properly The patient’s block is actually working but they aren’t as numb… which is appropriate The patient is ready to push The patient has developed a comorbidity (chorio vs. uterine rupture vs. something else)

Question 44

How do you treat hypotension?

Answer 44

Left or right uterine displacement fluid bolus 500cc-1L ephedrine 10 mg phenylephederine is better! Less fetal acidosis check for bradycardia/dysrhythmias check for alternative causes: Mg, hemmorhage, vagal

Question 45

Can a paraplegic deliver a baby vaginally?

Answer 45

yes!

Question 46

If the patient is "too numb" or "can't push". You are called because the patient can’t feel her legs and the OBs are concerned that she won’t be able to push.

Answer 46

DECREASE CONCENTRATION in the epidural Inject 5-10 cc NS through catheter

Question 47

The ___ receptor is THE cause of pruritis? What is the treatment?

Answer 47

mu mu antagonist!