Pregunta 1
Pregunta
Which of the following is a local anesthetic subject to inactivation by plasma esterases?
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a. Procaine
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b. Lidocaine
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c. Prilocaine
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d. Mepivacaine
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e. Bupivacaine
Pregunta 2
Pregunta
Procaine differs from lidocaine in that
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a. Procaine is a p-aminobenzoic acid ester and lidocaine is not
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b. Lidocaine is a meta-aminobenzoic acid ester and procaine is not
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c. The duration of action of procaine is longer than that of an equal total dose of lidocaine
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d. Procaine hydrochloride is metabolized into diethylaminoethanol and benzoic acid.
Pregunta 3
Pregunta
Which of the following local anesthetics would be expected to produce a sensitization reaction in a patient allergic to lidocaine?
a. Mepivacaine
b. Tetracaine
c. Procaine
d. Prilocaine
e. Dibucaine?
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a) (a), (b) and (c)
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b) (a), (d) and (e)
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c) (b) and (c) only
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d) (b), (c) and (d)
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e) (b), (d) and (e)
Pregunta 4
Pregunta
The hydrolysis of procaine occurs mainly in the
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a. Liver
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b. Lungs
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c. Plasma
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d. Muscles
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e. Kidneys
Pregunta 5
Pregunta
Which of the following is local anesthetic subject to inactivation by plasma esterases?
Respuesta
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a. Lidocaine
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b. Prilocaine
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c. Tetracaine
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d. Mepivacaine
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e. Bupivacaine
Pregunta 6
Pregunta
The activity of procaine is terminated by
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a. Elimination by the kidney
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b. Storage in adipose tissue
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c. Metabolism in the liver only
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d. Metabolism in the liver and by pseudocholinesterase in the plasma
Pregunta 7
Pregunta
All of the following factors are significant determinants of the duration of conduction block with amide-type local anesthetics EXCEPT the
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a. pH of tissues in the area of injection
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b. Degree of vasodilatation caused by the local anesthetic
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c. Blood plasma cholinesterase levels
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d. Blood flow through the area of conduction block
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e. Concentration of the injected anesthetic solution
Pregunta 8
Pregunta
Which of the following is contraindicated for a patient who had an allergic reaction to procaine six months ago?
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a. Nerve block with lidocaine
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b. Topical application of lidocaine
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c. Topical application of tetracaine
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d. Infiltration with an antihistamine
Pregunta 9
Pregunta
Bupivacaine (Marcaine) has all of the following properties relative to lidocaine (Xylocaine) EXCEPT
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a. Is more toxic
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b. Is an ester-type local anesthetic
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c. Has a slower onset of action
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d. Has a longer duration of action
Pregunta 10
Pregunta
Amide-type local anesthetics are metabolized in the
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a. Serum
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b. Liver
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c. Spleen
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d. Kidney
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e. Axoplasm
Pregunta 11
Pregunta
The duration of action of lidocaine would be increased in the presence of which of the following medications?
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a. Prazosin
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b. Propranolol
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c. Hydrochlorothiazide
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d. Lisinopril
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e. Digoxin
Pregunta 12
Pregunta
Severe liver disease least affects the biotransformation of which of the following?
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a. Lidocaine
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b. Procaine
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c. Prilocaine
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d. Mepivacaine
Pregunta 13
Pregunta
A patient has been given a large volume of a certain local anesthetic solution and subsequently develops cyanosis with methemoglobinemia. Which of the following drugs most likely was administered?
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a. Procaine
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b. Prilocaine
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c. Dibucaine
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d. Lidocaine
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e. Mepivacaine
Pregunta 14
Pregunta
Use of prilocaine carries the risk of which of the following adverse effects?
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a. Porphyria
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b. Renal toxicity
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c. Gastric bleeding
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d. Methemoglobinemia
Pregunta 15
Pregunta
The most probable cause for a serious toxic reaction to a local anesthetic is
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a. Psychogenic
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b. Deterioration of the anesthetic agent
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c. Hypersensitivity to the vasoconstrictor
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d. Hypersensitivity to the local anesthetic
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e. Excessive blood level of the local anesthetic
Pregunta 16
Pregunta
High plasma levels of local anesthetics may cause
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a. Inhibition of peristalsis
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b. stimulation of baroreceptors resulting in severe hypotension
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c. Inhibition of the vagus nerve to the heart
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d. Depression of inhibitory neurons in the CNS
Pregunta 17
Pregunta
Unfortunately, you injected your lidocaine intra-arterially. The first sign of lidocaine toxicity that might be seen in the patient would be
Pregunta 18
Pregunta
The first sign that your patient may be experiencing toxicity from too much epinephrine would be
Pregunta 19
Pregunta
Which disease condition would make the patient most sensitive to the epinephrine in the local anesthetic?
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a. Grave’s disease
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b. Diabetes
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c. HIV
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d. Alcoholism
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e. Schizophrenia
Pregunta 20
Pregunta
Cardiovascular collapse elicited by a high circulating dose of a local anesthetic may be caused by
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a. Syncope
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b. Vagal stimulation
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c. Histamine release
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d. Myocardial depression
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e. Medullary stimulation
Pregunta 21
Pregunta
The most serious consequence of systemic local anesthetic toxicity is
Pregunta 22
Pregunta
Hypotensive shock may result from excessive blood levels of each of the following local anesthetics EXCEPT
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a. Cocaine
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b. Procaine
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c. Lidocaine
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d. Tetracaine
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e. Mepivacaine
Pregunta 23
Pregunta
Which of the following anesthetic drugs produces powerful stimulation of the cerebral cortex?
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a. Cocaine
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b. Procaine
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c. Lidocaine
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d. Tetracaine
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e. Mepivacaine
Pregunta 24
Pregunta
Local anesthetics block nerve conduction by
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a. Depolarizing the nerve membrane to neutrality
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b. Increasing membrane permeability to K+
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c. Increasing membrane permeability to Na+
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d. Preventing an increase in membrane permeability to K+
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e. Preventing an increase in membrane permeability to Na+
Pregunta 25
Pregunta
Which of the following is true regarding the mechanism of action of local anesthetics?
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a. Usually maintain the nerve membrane in a state of hyperpolarization
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b. Prevent the generation of a nerve action potential
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c. Maintain the nerve membrane in a state of depolarization
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d. Prevent increased permeability of the nerve membrane to potassium ions
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e. Interfere with intracellular nerve metabolism
Pregunta 26
Pregunta
Local anesthetic agents prevent the generation of nerve impulses by
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a. Decreasing threshold for stimulation
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b. Decreasing resting membrane potential
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c. Decreasing inward movement of sodium ion
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d. Increasing inward movement of potassium ion
Pregunta 27
Pregunta
Local anesthetics interfere with the transport of which of the following ions during drug-receptor interaction
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a. Sodium
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b. Calcium
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c. Chloride
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d. Potassium
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e. Magnesium
Pregunta 28
Pregunta
If the pH of an area is lower than normal body pH, the membrane theory of local anesthetic action predicts that the local anesthetic activity would be
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a. Greater, owing to an increase in the free-base form of the drug
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b. Greater, owing to an increase in the cationic form of the drug
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c. Less, owing to an increase in the free-base form of the drug
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d. Less, owing to a decrease in the free-base form of the drug
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e. None of the above
Pregunta 29
Pregunta
A local anesthetic injected into an inflamed area will NOT give maximum effects because
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a. The pH of inflamed tissue inhibits the release of the free base
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b. The drug will not be absorbed as rapidly because of the decreased blood supply
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c. The chemical mediators of inflammation will present a chemical antagonism to the anesthetic
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d. Prostaglandins stabilize the nerve membrane and diminish the effectiveness of the local anesthetic
Pregunta 30
Pregunta
The penetration of a local anesthetic into nervous tissue is a function of the
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a. Length of the central alkyl chain
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b. Lipid solubility of the ionized form
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c. Lipid solubility of the unionized form
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d. Ester linkage between the aromatic nucleus and the alkyl chain
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e. Amide linkage between the aromatic nucleus and the alkyl chain
Pregunta 31
Pregunta
At a pH of 7.8, lidocaine (pKa = 7.8) will exist in
Pregunta 32
Pregunta
The more rapid onset of action of local anesthetics in small nerves is due to
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a. The slightly lower pH of small nerves
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b. The greater surface-volume ratio of small nerves
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c. The increased rate of penetration resulting from depolarization
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d. Smaller nerves usually having a higher threshold
Pregunta 33
Pregunta
Which of the following statements are true regarding onset, degree and duration of action of local anesthetics?
a. The greater the drug concentration, the faster the onset and the greater the degree of effect
b. Local anesthetics block only myelinated nerve fibers at the nodes of Ranvier
c. The larger the diameter of the nerve fiber, the faster the onset of effect
d. The faster the penetrance of the drug, the faster the onset of effect
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a) (a), (b), and (c)
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b) (a), (b) and (d)
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c) (a) and (c) only
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d) (b), (c) and (d)
Pregunta 34
Pregunta
A dentist administers 1.8 ml of a 2% solution of lidocaine. How many mg of lidocaine did the patient receive?
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a. 3.6
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b. 9
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c. 18
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d. 36
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e. 180
Pregunta 35
Pregunta
Three ml of a local anesthetic solution consisting of 2% lidocaine with 1:100,000 epinephrine contains how many milligrams of each?
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a. 6 mg. lidocaine, 0.3 mg. epinephrine
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b. 6 mg. lidocaine, 0.03 mg. epinephrine
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c. 60 mg. lidocaine 0.3 mg. epinephrine
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d. 60 mg. lidocaine 0.03 mg epinephrine
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e. 600 mg lidocaine, 0.3 mg. epinephrine
Pregunta 36
Pregunta
The maximum allowable adult dose of mepivacaine is 300 mg. How many milliliters of 2% mepivacaine should be injected to attain the maximal dosage in an adult patient?
Respuesta
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a. 5
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b. 10
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c. 15
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d. 20
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e. 25
Pregunta 37
Pregunta
A recently introduced local anesthetic agent is claimed by the manufacturer to be several times as potent as procaine. The product is available in 0.05% buffered aqueous solution in 1.8 ml. cartridge. The maximum amount recommended for dental anesthesia over a 4-hour period is 30 mg. The amount is contained in approximately how many cartridges?
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a. 1-9
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b. 10-18
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c. 19-27
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d. 28-36
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e. Greater than 36
Pregunta 38
Pregunta
According to AHA guidelines, the maximum # of carpules of local anesthetic containing 1:200,000 epinephrine that can be used in the patient with cardiovascular disease is
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a. 1
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b. 2
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c. 3
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d. 4
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e. 11