Local anesthetics 3

Question 1

______________ removes local anesthetics from its site of action.

Answer 1

Vascular uptake

Question 2

The rate of vascular uptake has a profound effect on

Answer 2

the plasma level of local anesthetic (risk of toxicity)

Question 3

The more ________________ the site, the higher the plasma concentration of local anesthetic.

Answer 3

vascular

Question 4

Order the sites from most to least vascular:

Answer 4

IV> tracheal>interpleural>intercostal>caudal >epidural> brachial plexus > femoral >sciatic > subcutaneous

Question 5

What factors reduce the rate of vascular uptake?

Answer 5

plasma protein binding (they behave like a reservoir)
rapid metabolism in the plasma (ester-type local anesthetics)
addition of a vasoconstrictor

Question 6

Factors that influence vascular uptake and Cp include

Answer 6

site of injection
tissue blood flow
physiochemical properties of local anesthetic
metabolism
addition of vasoconstrictor

Question 7

The same amount of local anesthetic injected at two different sites will

Answer 7

produce different plasma concentrations as a direct result of the blood flow each location receives

Question 8

What is the Mnemonic for remembering tissue blood flow?

Answer 8

I Think Illogical Imposters Can’t Educate But Fabulous Schools Should
IV–> tracheal–> interpleural–> intercostal–> caudal–> epidural –> brachial plexus–> femoral–> sciatic –> subcutaneous

Question 9

Local anesthetics preferentially bind to

Answer 9

alpha 1 acid glycoprotein but they also bind to albumin

Question 10

The _______ also act as a reservoir that removes local anesthetic from the circulation and limits plasma concentration

Answer 10

lungs

Question 11

In the circulation, ____________ helps limit the peak plasma concentration

Answer 11

plasma protein binding

Question 12

Amides are metabolized by

Answer 12

P450 enzymes in the liver

Question 13

Esters are metabolized by

Answer 13

pseudocholinesterase in the plasma

Question 14

The addition of a vasoconstrictor such as epinephrine or phenylephrine will

Answer 14

decrease systemic absorption by up to one-third and prolong the duration

Question 15

The addition of _________________ extends the duration of a brachial plexus block

Answer 15

dexamethasone

Question 16

What is exparel?

Answer 16

a newer formulation of bupivacaine indicated for single-use infiltration into the surgical site to provide post-surgical analgesia

Question 17

Benefits of exparel include

Answer 17

duration of action lasting up to several days + reduction in opioid consumption

Question 18

What is the maximum dose of exparel?

Answer 18

266 mg

Question 19

How does exparel work?

Answer 19

aqueous droplets of bupivacaine are housed inside a liposomal suspension
as the lipid membranes in the suspension erode and reorganize over time, bupivacaine is released in a predictable way

Question 20

Exparel is contraindicated for

Answer 20

paracervical block in the obstetric population

Question 21

Exparel is not recommended for

Answer 21

epidural anesthesia
intrathecal anesthesia
intraarticular administration
during pregnancy

Question 22

Exparel should be used in caution for patients with

Answer 22

hepatic and/or renal dysfunction

Question 23

Co-administration of other local anesthetics with Exparel can

Answer 23

disrupt the liposomal suspension causing immediate release of bupivacaine

Question 24

What are the rules for administering lidocaine and Exparel to a patient:

Answer 24

after infiltrating lidocaine–> no liposomal bupivacaine for at least 20 minutes
after infiltrating liposomal bupivacaine–> no lidocaine (in any form) for at least 96 hours

Question 25

What is the maximum dose for levobupivacaine

Answer 25

2 mg/kg

Question 26

What is the maximum dose for bupivacaine?

Answer 26

2.5 mg/kg

Question 27

What is the maximum dose for bupivacaine + epinephrine?

Answer 27

3 mg/kg

Question 28

What is the maximum dose for ropivacaine?

Answer 28

3 mg/kg

Question 29

What is the maximum dose for lidocaine?

Answer 29

4.5 mg/kg

Question 30

What is the maximum dose for lidocaine + epineprine?

Answer 30

7 mg/kg

Question 31

What is the maximum dose for mepivacaine?

Answer 31

7 mg/kg

Question 32

What is the maximum dose for prilocaine?

Answer 32

8 mg/kg

Question 33

What is the maximum dose for procaine?

Answer 33

7-10 mg/kg

Question 34

What is the maximum dose for chloroprocaine?

Answer 34

11 mg/kg

Question 35

What is the maximum dose for chloroprocaine + epinephrine?

Answer 35

14 mg/kg

Question 36

What is the max total dose for levobupivacaine?

Answer 36

150 mg

Question 37

What is the max total dose for bupivacaine?

Answer 37

175 mg

Question 38

What is the max total dose for bupivacaine + epinephrine?

Answer 38

200 mg

Question 39

What is the max total dose for ropivacaine?

Answer 39

200 mg

Question 40

What is the max total dose for lidocaine?

Answer 40

300 mg

Question 41

What is the max total dose for mepivacaine?

Answer 41

400 mg

Question 42

What is the max total dose for lidocaine + epi?

Answer 42

500 mg

Question 43

What is the max total dose for prilocaine?

Answer 43

if <70 kg–> 500 mg
if >70 kg–> 600 mg

Question 44

What is the max total dose for procaine?

Answer 44

350-600

Question 45

What is the max total dose for chloroprocaine?

Answer 45

800 mg

Question 46

What is the max total dose for chloroprocaine + epi?

Answer 46

1000 mg

Question 47

At what plasma concentration would you expect lidocaine to produce seizures?

Answer 47

10-15 mcg/mL

Question 48

Local anesthetic toxicity syndrome affects the

Answer 48

central nervous system and cardiovascular system

Question 49

The most common cause of LAST is

Answer 49

inadvertent intravascular injection during regional anesthesia