Locals

Question 1

which of the following properties of epidurally administered local anesthetics determines the extent to which epinephrine will prolong the duration of blockade?

A. molecular weight
B. Lipid Solubility
C. pKa
D. Concentration

Answer 1

B. Lipid Solubility

Question 2

The action of epidural narcotics is antagonized by the prior or concomitant administration of which of the following epidurally administered local anesthetics?

A. Lidocaine
B. Bupivacaine
C. Ropivacaine
D. Chloroprocaine

Answer 2

D. Chloroprocaine

Question 3

Refractory cardiac arrest is MOST likely after the rapid unintentional IV injection of which of the following local anesthetics?

A. Lidocaine
B. Bupivacaine
C. Ropivacaine
D. Chloroprocaine

Answer 3

B. Bupivacaine

Question 4

Transient neurologic syndrome (TNS) is MOST commonly seen after the spinal anesthetic injection of which local anesthetic?

A. Lidocaine
B. Bupivacaine
C. Prilocaine
D. Tetracaine

Answer 4

A. Lidocaine

Question 5

Which local anesthetic has the MOST rapid metabolism in the maternal and fetal blood?

A. Lidocaine
B. Bupivacaine
C. Ropivacaine
D. Chloroprocaine

Answer 5

D. Chloroprocaine

Question 6

Produces reversible conduction blockade of impulses along the _____ and _____ nerve pathways

Answer 6

central and peripheral nerve pathways

Question 7

1st local anesthetic

Answer 7

Cocaine 1884

Question 8

1st synthetic local (ester)

Answer 8

Procaine 1905

Question 9

1st amide local

Answer 9

Lidocaine 1943

Question 10

lipophilic and hydrophilic portions separated by _____

Answer 10

hydrocarbon

Question 11

The lipophilic portion is the

Answer 11

Benzene ring (necessary for activity)

Question 12

Ester

Answer 12

• • CO-

Question 13

Amide

Answer 13

• • NHC-

Question 14

Quaternary amine

Answer 14

Hydrophilic

Question 15

What’s the benefit of S enantiomers?

Answer 15

less neuro and cardio-toxic

Question 16

Mechanism of action:

Answer 16

Inhibit Na+ ions through the selective Na+ channels

-slows rate of depolarization
Threshold potential not reached= no action potential propogated

DOES NOT ALTER:
-resting membrane potential
-Threshold potential

Question 17

Alpha subunit:

Answer 17

allows ion conduction and binds LA

Question 18

LAs bind to Na+ channels only in the ____ and ___ states

Answer 18

Active and inactivated

Question 19

Nerves with more activity =

Answer 19

faster blockade

Question 20

Other sites of action

Answer 20

Voltage-dependent potassium channels
Calcium ion currents (L-type)
G protein-coupled receptors

Question 21

Cm=

Answer 21

Minimum concentration to produce conduction blockade

Question 22

Factors that increase Cm:

Answer 22

Larger diameter

Question 23

Factors that decrease Cm:

Answer 23

Higher frequency
Higher pH

Question 24

Inhibit Na+ ions passage through ion-selective Na+ channels

Answer 24

-Slows rate of depolarization
-Threshold potential not reached
-No action potential propagated

Question 25

Locals don’t alter the ____ and ____ of the membrane potential

Answer 25

Resting membrane potential
Threshold potential

Question 25

Locals don’t alter the ____ and ____ of the membrane potential

Answer 25

Resting membrane potential
Threshold potential