Deck 10: Local Anesthetics

Question 1

EMLA is a topical anesthetic containing 2.5% of each of two ingredients.You use the Physicians' Desk Reference and determine that the two ingredients are:

A) Lidocaine and epinephrine
B) Procaine and lidocaine
C) Lidocaine and prilocaine
D) None of these are correct.

Answer 1

Lidocaine and prilocaine

Question 2

Using the Drug Facts and Comparisons reference manual,you learn that the ester local anesthetics have a short to moderate duration of action and that the drug group that falls into this category includes:

A) Procaine, benzocaine, and tetracaine
B) Lidocaine, bupivacaine, and mepivacaine
C) Ethyl chloride, GumEase, and EMLA cream
D) None of these are correct.

Answer 2

Procaine, benzocaine, and tetracaine

Question 3

Why are local anesthetic agents that contain epinephrine contraindicated for use in the areas of the fingers,toes,ears,nose,or penis?

A) Epinephrine in these areas may lead to ischemia and gangrene.
B) Epinephrine in these areas may lead to reflex sympathetic dystrophy.
C) Epinephrine in these areas may lead to painful peripheral vascular disease.
D) None of these are correct.

Answer 3

Epinephrine in these areas may lead to ischemia and gangrene.

Question 4

Overdose of local anesthetics can lead to CNS depression.What treatment would you use to reverse the effects of the local anesthetics?

A) Barbiturates and diazepam (Valium)
B) Epinephrine and diazepam (Valium)
C) Barbiturates and epinephrine
D) None of these are correct.

Question 5

Cocaine was the first local anesthetic to be discovered.Explain the reason why cocaine can't be used by injection.

A) Injected cocaine produces vasodilation.
B) Injected cocaine produces vasoconstriction.
C) Injected cocaine relaxes vascular smooth muscle.
D) Injected cocaine produces hypotension.

Question 6

Using the Physicians' Desk Reference available in the office,you determine that the amide local anesthetics have a moderate to long duration of action and that the drug group that falls into this category includes:

A) Procaine, benzocaine, and tetracaine
B) Lidocaine, bupivacaine, and mepivacaine
C) Ethyl chloride, GumEase, and EMLA cream
D) None of these are correct.

Question 7

Identify the type of impulse that is carried to the brain by the sensory neurons.

A) Heat and cold
B) Pain
C) Touch
D) All of these are correct.

Question 8

Identify the most commonly used local anesthetic technique.

A) Regional nerve block
B) Infiltration anesthesia
C) Intradermal anesthesia
D) Cryoanesthesia

Question 9

Identify the most common clinical use of local anesthetics.

A) Abolish painful stimulation prior to surgical procedures.
B) Abolish painful stimulation prior to tooth extractions.
C) Abolish painful stimulation prior to childbirth.
D) All of these are correct.

Question 10

Using your knowledge of the mechanism of action of the local anesthetics,you determine that loss of sensory perception and motor function may persist for a short time after application.You instruct patients that:

A) They will not be able to respond to hot or cold stimuli.
B) They should avoid eating or drinking for 1 hour if oral topical anesthetics were used.
C) They will not be able to respond to scratching.
D) All of these are correct.

Question 11

Explain the reason why local anesthetics that are given by injection occasionally contain epinephrine.

A) Epinephrine acts as a preservative to maintain an extended shelf life.
B) Epinephrine counteracts the vasodilation that occurs with local anesthetic use.
C) Epinephrine counteracts the vasoconstriction that occurs with local anesthetic use.
D) None of these are correct.

Question 12

Bupivacaine contains a black box warning against epidural use of the 0.75% concentration during labor and delivery.Select the reason why the 0.75% strength is contraindicated for this use.

A) Cardiac arrest with difficult resuscitation may occur.
B) Convulsions may occur.
C) Ischemia and gangrene may occur.
D) None of these are correct.

Question 13

What would be the key selling point to use when explaining to a patient that the physician is implementing the use of cryoanesthesia for the removal of superficial lesions?

A) There is no need for an injection.
B) Cryoanesthesia has a short duration of action, so it will wear off in a short period of time.
C) The application requires only a 30- to 60-second painless spray of ethyl chloride, a refrigerant product.
D) All of these are correct.

Question 14

Implementing the use of potent local anesthetics can lead to adverse effects on the central nervous system.These effects can lead to nervousness,excitation,tremors,and convulsions.The probable cause of these effects is:

A) Depression of the activity of the cerebral cortex
B) Hypersensitivity to the local anesthetics
C) Stimulation of the cerebral cortex
D) None of these are correct.

Question 15

Explain why local anesthetics are valuable as a treatment for pain management.

A) Local anesthetics stimulate sensory nerves at low doses that increase the response of the motor nerves.
B) Local anesthetics block sensory nerves at low doses that do not inhibit motor nerve function.
C) Local anesthetics interact with nerve membranes to increase nerve conduction.
D) None of these are correct.

Question 16

Match lidocaine,a local anesthetic,to a condition it is used to treat.

A) Rash
B) Hypotension
C) Cardiac arrhythmias
D) None of these are correct.

Question 17

Peripheral nerve fibers and their neurons are classified according to the:

A) Diameter of the axon
B) Ability of the nerve to conduct impulses quickly or slowly
C) Amount of the protective myelin sheath that covers the nerve
D) All of these are correct.

Question 18

Injection of local anesthetics is used for surgical,suturing,and obstetrical procedures.Using your knowledge of this drug class,what product should be used to relieve the pain of postherpetic neuralgia?

A) Lidoderm 5% transdermal patch
B) Ethyl chloride topical spray
C) Menthol topical spray
D) None of these are correct.

Question 19

Explain how local anesthetics affect cardiac function.

A) Local anesthetics depress the function of the cardiac conduction system.
B) Local anesthetics produce tachycardia.
C) Local anesthetics cause hypertension.
D) All of these are correct.

Question 20

The topical anesthetic procaine has been shown to prevent or inhibit the action of the sulfonamide class of antibiotics.Select the reason why this inhibition of action occurs.

A) Procaine is metabolized to p-aminobenzoic acid, which has an antagonistic effect with the sulfonamides for the bacterial site of action.
B) Procaine is metabolized to p-aminobenzoic acid, which has an additive effect with the sulfonamides for the bacterial site of action.
C) Procaine is metabolized to p-aminobenzoic acid, which has a synergistic effect with the sulfonamides for the bacterial site of action.
D) None of these are correct.

Question 21

Using duration of action as a guide,select the group which has the local anesthetics listed in order of increasing duration of action.

A) Novocain, Lidoderm, GumEase
B) Lidoderm, GumEase, Novocain
C) GumEase, Novocain, Lidoderm
D) None of these are correct.

Question 22

Because of the contraindications of use of the amide local anesthetics,patients who have any form of liver disease should be monitored for:

A) Rapid metabolism of the amide anesthetic agent
B) Accumulation of the amide metabolites
C) Decreased amide anesthetic clearance
D) None of these are correct.

Question 23

When differentiating between local and general anesthetics,general anesthetics:

A) Cause total loss of consciousness
B) Stimulate the activity of the CNS
C) Can limit the response to one area of the body
D) None of these are correct.

Question 24

A patient comes in to see the doctor because he is complaining of pruritus and facial swelling and does not know the reason why.He states that he has been using all of his usual medications and has also been using OTC benzocaine on a regular basis for the last 2 to 3 weeks for insect bites.Where do you focus your attention as to the probable cause of his symptoms?

A) Hypersensitivity reaction to PABA
B) Severe drug-produced vasoconstriction
C) Hypersensitivity reaction to epinephrine
D) None of these are correct.

Question 25

When differentiating between injectable bupivacaine,which is available as a 0.25% to 0.75% solution with a duration of action of 2 to 4 hours,and injectable procaine,which is available as a 1% to 2% solution with a duration of action of 15 minutes to 1 hour,the choice of agent used for injection around the spinal cord is primarily determined by the:

A) Onset of action required
B) Concentration of the product
C) Duration of action required
D) None of these are correct.

Question 26

Select the statement that best explains potency.

A) Potency is the ability to increase velocity of nerve conduction.
B) Potency is the ability to produce a nerve block at a relatively low dose.
C) Potency is the ability to produce a heightened conduction of nerve impulses.
D) None of these are correct.

Question 27

Local anesthetics eliminate the response to pain by inhibiting the sensory nerves that carry painful stimuli to the CNS.Select the correct mechanism of action of the local anesthetics.

A) Sodium ions are blocked from passing in through the cell membrane.
B) Nerve depolarization is prevented.
C) Potassium ions are blocked from passing out through the cell membrane.
D) All of these are correct.

Question 28

Injections of anesthetic agents must be administered slowly,and the patient must be monitored for vital signs.Select the signs to look for that could indicate central nervous system toxicity.

A) Dizziness, blurred vision, and slurred speech
B) Nausea, vomiting, and diarrhea
C) Dizziness, blurred vision, and headache
D) None of these are correct.

Question 29

When comparing the ester local anesthetics with the amide local anesthetics based on the criteria of onset of action,the ester local anesthetics:

A) Have a short or moderate duration of action due to metabolism in the blood and skin
B) Have a longer duration of action due to metabolism in the liver
C) Have the same duration of action as the amide local anesthetics due to the metabolism in the blood and skin
D) None of these are correct.

Question 30

Select the primary reason why local anesthetic agents should not be applied to damaged,open,or broken skin.

A) The broken skin allows the anesthetic agent to reach the blood vessels.
B) The patient may develop convulsions.
C) The patient may develop hypotension.
D) All of these are correct.