T5 Ch 9 & 10 Flashcards
The following are characteristics of the ideal local anesthetic except:
a. Sterilization by autoclave
b. Slow onset
c. Reversible
d. Absence of local reactions
b. Slow onset
Local anesthetics block the conduction of nerve impulses by decreasing the permeability of the nerve cell membrane to
a. Potassium ions
b. Sodium ions
c. fat soluble ions
d. cations
b. Sodium ions
In the presence of an acidic environment, such as infection or inflammation, the amount of free base is reduced; therefore __________ of the local anesthetic is in the ionized form, making anesthesia __________ difficult.
a. More, more
b. More, less
c. Less, more
d. Less, less
a. More, more
Reducing the rate of systemic absorption of a local anesthetic is important when it is used in dentistry because:
a. Otherwise, too large an area would be anesthetized.
b. If not, the anesthesia would not last long enough to complete a dental procedure.
c. The chance of systemic toxicity is reduced.
d. Local anesthesia is associated with respiratory depression.
c. The chance of systemic toxicity is reduced.
Addition of vasoconstrictor to local anesthetic (1) reduces blood supply to the area, (2) increases blood supply to the area, (3) limits systemic absorption, (4) increases systemic absorption, (5) reduces systemic toxicity, (6) increases systemic toxicity. Which of the three pairs of choices is correct?
a. 1, 3, 5
b. 1, 4, 5
c. 2, 3, 5
d. 2, 3, 6
e. 2, 4, 6
a. 1, 3, 5
Local anesthetics cross:
a. The placenta and blood-brain barrier
b. The placenta but not the blood-brain barrier
c. The blood-brain barrier but not the placenta
d. Neither the placenta nor the blood-brain barrier
a. The placenta and blood-brain barrier
Amide local anesthetics are metabolized:
a. By being hydrolyzed by plasma pseudocholinesterases
b. Primarily by the liver
c. In the spleen
d. Minimally and are excreted virtually unchanged
b. Primarily by the liver
Which nerve function is usually the first to be lost?
a. Touch
b. Warmth
c. Pressure
d. Autonomic
e. Pain
d. Autonomic
The maximal safe dose of lidocaine 2% with 1:100,000 epinephrine is approximately __________ cartridges.
a. 3
b. 6.5
c. 8.5
d. 11.5
c. 8.5
Which of the following local anesthetics is safest to use for dental treatment for a pregnant woman?
a. Mepivacaine
b. Lidocaine
c. Articaine
d. Bupivacaine
b. Lidocaine
Epinephrine is combined with local anesthetics so as to:
a. Enhance absorption
b. Prolong duration
c. Delay onset
d. Increase potency
b. Prolong duration
Lidocaine with epinephrine 1:100,000 provides a __________ duration of pulpal anesthesia.
a. 30-minute
b. 30- to 60-minute
c. 60- to 90-minute
d. 90-minute or more
c. 60- to 90-minute
Which of the following statements is true of mepivacaine?
a. Cross-allergenicity has been demonstrated between mepivacaine and other currently available amides.
b. Mepivacaine is effective topically.
c. Mepivacaine can be used as a 3% solution without a vasoconstrictor.
d. The benefit of a shorter duration of anesthesia warrants eliminating the vasoconstrictor.
c. Mepivacaine can be used as a 3% solution without a vasoconstrictor.
Which of the following local anesthetics has the longest duration of action?
a. Lidocaine
b. Mepivacaine
c. Prilocaine
d. Bupivacaine
d. Bupivacaine
Plain anesthetics without vasoconstrictor will exhibit a__________ duration of action and result in a __________ buildup of a systemic blood level.
a. Shorter, less-rapid
b. Shorter, more-rapid
c. Longer, less-rapid
d. Longer, more-rapid
b. Shorter, more-rapid
Patients with uncontrolled high blood pressure, hyperthyroidism, angina pectoris, and cardiac arrhythmias and those who have had a myocardial infarction or cerebrovascular accident in the past __________ should make an appointment for elective dental treatment after their medical condition is under control.
a. 6 weeks
b. 3 months
c. 6 months
d. 12 months
c. 6 months
The maximal safe dose of epinephrine for the cardiac patient is __________ mg.
a. 0.02
b. 0.04
c. 0.2
d. 0.4
b. 0.04
Which of the following agents is the most common topical local anesthetic?
a. Lidocaine
b. Benzocaine
c. Tetracaine
d. Dyclonine
b. Benzocaine
Oraqix is the combination of which two anesthetics?
a. Articaine and bupivacaine
b. Lidocaine and prilocaine
c. Benzocaine and tetracaine
d. Lidocaine and articaine
b. Lidocaine and prilocaine
True OR False
The rate of local anesthetic absorption is increased by the presence of local inflammation.
False
True OR False
For lengthy dental procedures, bupivacaine is recommended over lidocaine because bupivacaine has a longer duration of action.
True
True OR False
A patient can produce endogenous epinephrine far in excess of that administered in dentistry in the presence of inadequate anesthesia.
True
Nitrous oxide, as used in the dental office, maintains the patient in stage:
a. I
b. II
c. III
d. IV
a. I
Nitrous oxide has:
a. Rapid onset and high solubility in blood
b. Rapid onset and low solubility in blood
c. Rapid onset and low minimal alveolar concentration (MAC)
d. Slow onset and high MAC
b. Rapid onset and low solubility in blood
The average percentage of nitrous oxide required for patient comfort is:
a. 10%
b. 25%
c. 35%
d. 50%
c. 35%
Nitrous oxide cylinders are __________ and oxygen cylinders are __________ (1) red, (2) green, (3) blue, (4) orange, (5) tan
a. 1, 2
b. 3, 2
c. 2, 4
d. 3, 4
e. 3, 5
b. 3, 2
True OR False
The more soluble the anesthetic is in body tissues, the more rapid the onset and recovery will be.
False
True OR False
Nitrous oxide is a complete anesthetic.
False
A common property of all General Anesthetics is that they are all
a. very hydrophilic
b. absorbed slowly
c. very lipophilic
d. unable to cross the blood-brain barrier
c. very lipophilic
When the sodium channels open and sodium ions diffuse into the cell, this is called:
a. action potential
b. depolarization
c. repolarization
d. hyperpolarization
b. depolarization
At the termination of a N2O/O2 sedation procedure, the patient should be placed on 100% oxygen for at least __________ minutes.
a. 2
b. 5
c. 8
d. 11
b. 5
