LOCAL ANESTHETICS | Basic

Question 1

Systemic absorption of local anesthetic is GREATEST after injection for:

A. Epidural
B. Femoral Nerve Blocks
C. Intercostal nerve Blocks
D. Sciatic Nerve Blocks

Answer 1

C. Intercostal nerve Blocks

Question 2

This is the active metabolite of Lidocaine (80% of its local anesthetic activity)?

Answer 2

Monoethylglycinexylidide

Question 3

ORDER OF SENSITIVITY (Most to Least)

Answer 3

B
C
A - delta
A - beta
A - alpha

Question 4

Blockade recovery is fastest at:

A. C fibers

B. B fibers

C. A-delta

D. A -beta

Answer 4

A. C fibers

Question 5

MOA of Local Anesthetics:

Answer 5

REVERSIBLY bind the INTRACELLULAR portion of the voltage gated Na channels –> INHIBITS transmission of nerve impulses.

• Preferentially bind Vgated Na channel in the OPEN or INACTIVE STATE!

Question 6

What local anesthetic is least likely to produce sustained elevation in blood levels because of very rapid hydrolysis in the blood.

Answer 6

CHLOROPROCAINE

*Addition of chlorine atom to the benzene ring of procaine form this local anesthetic. 3x faster in hydrolysis.

Question 7

Is defined as the pH at which the ionized and unionized forms exist in equal concentrations

Answer 7

pKa

Question 8

What is the primary emergency treatment of methemoglobinemia?

Answer 8

Methylene blue 1-2 mg/kg

Question 9

What ester LA undergoes significant metabolism in the liver and therefore does not conform with the hydrolysis metabolism of esters?

Answer 9

COCAINE

Question 10

This is a laboratory evaluation for suspected atypical pseudocholinesterase facilitated by measurement of the DEGREE of enzyme suppression by dibucaine?

Answer 10

Dibucaine number

Question 11

Max dose of Methylene Blue?

Answer 11

7-8 mg/kg

Question 12

Least like to cause a vasodilatory effect among amide local anesthetic?

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

Answer 12

Mepivacaine

Mepivacaine lacks vasodilatory activity.

Question 13

Cardiotoxic plasma concentration of BUPIVACAINE

A. 8-10 ug/mL

B. 5 ug/mL

C. 15 ug/mL

Answer 13

A. 8-10 ug/mL

Question 14

Which molecular structure is responsible for determining its classification as amide or ester?

A. Hydrocarbon chain

B. Aromatic ring

Answer 14

A. Hydrocarbon chain

Question 15

__ is the lipophilic portion of LA molecular structure:

A. Aromatic ring

B. Hydrocarbon chain

C. Tertiary amine

Answer 15

A. Aromatic ring