Local anesthetics work by blocking ________ channels, preventing cell membrane depolarization.

Which of the following local anesthetics has the longest duration of action?

• Lidocaine

• Bupivacaine

• Procaine

• Benzocaine

What is the order of nerve fiber sensitivity to local anesthetics?

• Aδ > C > Aα

• C > Aδ > Aα

• Aα > C > Aδ

• Aδ > Aα > C

What effect do vasoconstrictors have when added to local anesthetics?

• Reduce the duration of the anesthetic effect

• Increase systemic absorption and toxicity

• Delay absorption and increase safety

• Reduce the intensity of the anesthetic effect

Adding ________ to lidocaine increases the duration and intensity of the anesthetic effect by reducing systemic absorption.

What is the major risk of administering bupivacaine?

• Methemoglobinemia

• Severe hypotension

• Severe cardiac toxicity

• Severe allergic reactions

Which regional anesthesia technique involves injecting the anesthetic near a nerve plexus or nerve trunk?

• Surface anesthesia

• Peripheral nerve block

• Intra-articular anesthesia

• Epidural anesthesia

What effect does hyaluronidase have when added to local anesthetics?

• Increases tissue penetration

• Reduces tissue penetration

• Slows down the onset of analgesic activity

Which of the following local anesthetics is an ester?

• Mepivacaine

• Ropivacaine

• Lidocaine

• Procaine

Local anesthetics are less effective in ________ tissues due to the low pH, which affects absorption.