Anesthesia Buddy: Pharm I

Which intravenous agent is also known as

2, 6-diisopropylphenol)?

1. A) Etomidate

B) Ketamine

C) Propofol

D) Midazolam

1. Correct answer: C

Explanation:

Propofol is a substituted isopropylphenol (2,6-

diisopropylphenol)

Quick tip: Clearance of propofol from the plasma

exceeds hepatic blood flow

2. Which component is NOT part of

propofol formulation?

A) Egg lecithin

B) Soybean oil

C) Glycerol

D) Silica gel

2. Correct answer: D

Explanation:

Propofol consists of a 1% solution in an

aqueous solution of 10% soybean oil, 2.25%

glycerol, and 1.2% purified egg phosphatide

Silica is added to soda lime absorbent

granules to provide hardness and minimize

alkaline dust formation

Quick tip: Propofol formulation is composed of

long chain triglycerides (soybean oil and egg

lecithin)

3. Which compound is added to generic

propofol formulations as an

antimicrobial?

A) Sodium metabisulfite

B) Hydroxycobalamin

C) Sodium nitrite

D) Sodium thiosulfate

3. Correct answer: A

Explanation:

Generic formulation of propofol contains

sodium metabisulfite as the preservative

Sodium thiosulfate, sodium nitrite and

hydroxycobalamin are used in the treatment

of cyanide toxicity

Quick tip: Diprivan uses the preservative

disodium edetate

4. Which agent hyperpolarizes neurons by

increasing chloride conductance?

A) Lidocaine

B) Fentanyl

C) Propofol

D) Rocuronium

4. Correct answer: C

Explanation:

Propofol is a relatively selective modulator of

y-aminobutyric acid (GABAA)

Mechanism of action of propofol: Activation

of GABAA increases transmembrane chloride

conductance and results in hyperpolarization

of the postsynaptic cell membrane.

Subsequently, functional inhibition of the

postsynaptic neuron occurs.

Mechanism of action of lidocaine: blockade of

voltage-gated sodium channels

Mechanism of action of fentanyl:

Fentanyl binds to opioid receptors, especially the mu opioid receptor, which are coupled

to G-proteins

Mechanism of action of rocuronium: Non-

depolarizing neuromuscular blocking agent

that competes with acetylcholine on the

neuromuscular nicotinic receptors

Quick tip: GABA is the principal inhibitory

neurotransmitter in the brain

5. Which of the following effects is

INCREASED by propofol administration?

A) Systemic vascular resistance

B) Myocardial contractility

C) Preload

D) Respiratory depression

5. Correct answer: D

Explanation:

Propofol decreases blood pressure, systemic

vascular resistance, and preload

Negative inotropic effect may result due to

decrease in intracellular calcium availability

Propofol produces dose-dependent

depression of ventilation

Quick tip: In patients receiving propofol, hypoxic

pulmonary vasoconstriction seems to remain intact

6. Which effect is MOST likely to occur

from propofol administration?

A) Myoclonus

B) Increased cerebral blood flow

C) Increased intraocular pressure

D) Analgesia

6. Correct answer: A

Explanation:

Propofol administration has been associated

with myoclonus Propofol significantly decreases intraocular

pressure

Propofol does not relieve nociceptive pain

Propofol decreases cerebral metabolic rate for

oxygen (CMRO2), cerebral blood flow, and

intracranial pressure (ICP)

Quick tip: Propofol has the ability to produce

burst suppression on electroencephalography

(EEG)

7. Which intravenous agent possess

antioxidant properties?

A) Propofol

B) Midazolam

C) Etomidate

D) Ketamine

7. Correct answer: A

Explanation:

Propofol has potent antioxidant properties

similar to endogenous vitamin E

Quick tip: Propofol scavenges free radicals and

inhibits lipid peroxidation

8. Which intravenous agent is likely to

produce green color urine?

A) Propofol

B) Midazolam

C) Etomidate

D) Ketamine

8. Correct answer: A

Explanation:

Prolonged infusions of propofol can cause

excretion of green urine due to the presence

of phenols

Quick tip: Cloudy urine may occur after propofol

administration due urinary uric acid excretion

9. Which is NOT part of propofol infusion

syndrome?

A) Metabolic acidosis

B) Rhabdomyolysis

C) Kidney failure

D) Hypokalemia

9. Correct answer: D

Explanation:

Propofol infusion syndrome has been

described in patients after prolonged high

dose propofol infusions for longer than 24

hours

Common clinical findings associated with

propofol infusion syndrome include anion-

gap metabolic acidosis, cardiac dysfunction,

rhabdomyolysis, hypertriglyceridemia,

elevated liver enzymes, hyperkalemia, and

renal failure

Quick tip: Measurement of the anion gap can be

used to differentiate hyperchloremic metabolic

acidosis from lactic acidosis

10. Which intravenous agent possess long

chain triglycerides?

A) Propofol

B) Midazolam

C) Etomidate

D) Ketamine

10. Correct answer: A

Explanation:

Propofol formulation is composed of long

chain triglycerides (soybean oil and egg

lecithin)

Quick tip: Propofol does not prolong the QTc

interval on the electrocardiogram

11. Which effect is NOT likely to occur from

propofol administration?

A) Antiemetic effect

B) Antiprutitic effect

C) Anticonvulsant effect

D) Analgesic effect

11. Correct answer: D

Explanation:

Propofol possesses antiemetic, antipruritic

and anticonvulsant effects

Propofol does not relieve nociceptive pain

Quick tip: Regardless of anesthetic technique,

propofol administration reduces incidence of

postoperative nausea and vomiting

12. Which intravenous agent is a

phencyclidine derivative?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

12. Correct answer: D

Explanation:

Ketamine is a phencyclidine derivative that

produces dissociative anesthesia

Quick tip: Phencyclidine (PCP) is an illegal street

drug also known as angel dust

13. Which intravenous agent antagonizes

glutamate?

A) Midazolam

B) Dexmedetomidine

C) Etomidate

D) Ketamine

13. Correct answer: D

Explanation:

Ketamine inhibits activation of NMDA

receptors by glutamate and decreases

presynaptic release of glutamate

Quick tip: Glutamate is the most abundant

excitatory neurotransmitter in the brain

14. Which effect is NOT likely to occur from

ketamine administration?

A) Bronchodilation

B) Antisialogue

C) Increased cerebral oxygen consumption

(CMRO2)

D) Nystagmus

14. Correct answer: B

Explanation:

Ketamine increases cerebral blood flow and

cerebral oxygen consumption (CMRO2)

Ketamine produces anticholinergic effects

such as sympathomimetic action,

bronchodilation, and emergence delirium

Ketamine administration is associated with

nystagmus

Ketamine administration increases salivary

and tracheobronchial mucous gland

secretions

Quick tip: Ketamine may produce a sensation of

bodily detachment or floating in space

15. Which agent is most effective at

preventing emergence delirium from

ketamine administration?

A) Atropine

B) Physostigmine

C) Midazolam

D) Sevoflurane

15. Correct answer: C

Explanation:

Benzodiazepines such as midazolam have

proven most effective at reducing the

incidence of emergence delirium after

ketamine administration

Quick tip: Atropine may increase the incidence of

emergence delirium

16. Which intravenous agent is a

carboxylated imidazole?

A) Propofol

B) Fentanyl

C) Etomidate

D) Ketamine

16. Correct answer: C

Explanation:

Etomidate is a carboxylated imidazole–

containing compound

Quick tip: Midazolam and dexmedetomidine also

contain an imidazole nucleus

17. Which is CORRECT about the imidazole

ring of etomidate?

A) Imidazole ring closes at an acidic pH

B) Imidazole ring opens at physiologic pH

C) At an acidic pH, imidazole ring has

increased lipid solubility

D) When the imidazole ring is closed, lipid

solubility increases

17. Correct answer: D

Explanation:

The imidazole nucleus renders etomidate

water soluble at an acidic pH and lipid soluble

at physiologic pH

Quick tip: Etomidate 99% unionized at

physiologic pH

18. Which intravenous agent should be

avoided in patients with adrenal failure?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

18. Correct answer: C

Explanation:

Etomidate can transiently depress

adrenocortical function

Etomidate produces a dose-dependent

inhibition of the conversion of cholesterol to

cortisol

Quick tip: The enzyme inhibited by etomidate is

11-beta-hydroxylase

19. Which intravenous agent can inhibit

cortisol and aldosterone synthesis?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

19. Correct answer: C

Explanation:

Etomidate can transiently depress

adrenocortical function

Etomidate produces a dose-dependent

inhibition of the conversion of cholesterol to

cortisol

Quick tip: The enzyme inhibited by etomidate is

11-beta-hydroxylase

20. Which intravenous agent can inhibit 11-

beta-hydroxylase enzyme?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

20. Correct answer: C

Explanation:

Etomidate can transiently depress

adrenocortical function Etomidate produces a dose-dependent

inhibition of the conversion of cholesterol to

cortisol

Quick tip: The enzyme inhibited by etomidate is

11-beta-hydroxylase

21. Which intravenous agent is MOST likely

to cause postoperative nausea and

vomiting (PONV)?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

21. Correct answer: C

Explanation:

Negative effects associated with etomidate

administration include myoclonus, pain on

injection, adrenocortical suppression and

increased incidence of postoperative nausea

and vomiting

Quick tip: Myoclonus seems to occur due to

disinhibition of subcortical structures that

generally suppress extrapyramidal motor activity

22. Which agent is derived from barbituric

acid?

A) Propofol

B) Methohexital

C) Etomidate

D) Ketamine

22. Correct answer: B

Explanation:

The clinically used barbiturates are derived

from barbituric acid

Methohexital possess hypnotic properties,

lowers the seizure threshold, and causes

myoclonus on induction

Quick tip: The decreased anticonvulsant effect of

methohexital is useful during electroconvulsive

therapy

23. Which agent is likely to cause histamine

release and hypotension?

A) Propofol

B) Thiopental

C) Etomidate

D) Ketamine

23. Correct answer: B

Explanation:

Thiopental can cause an allergic reaction in

the absence of prior exposure (anaphylactoid

response)

Thiopental administration is associated with

direct release of histamine from tissue mast

cells

Quick tip: Barbiturates, especially

phenobarbital, produce liver enzyme induction

and may exacerbate acute intermittent porphyria

24. Which agent is SAFEST to administer to

patient with acute intermittent

porphyria?

A) Propofol

B) Thiopental

C) Etomidate

D) Ketamine

24. Correct answer: A

Explanation:

The porphyrias are a group of inherited

disorders of heme biosynthesis

Fasting, infection, dehydration and certain

drugs can trigger an acute crisis

Sedation is safe using propofol

Ketamine, etomidate, and thiopental are

considered unsafe and possibly

porphyrinogenic

Quick tip: The name porphyria is derived from

the Greek word for purple

25. Which agent decreases cAMP and

inhibits the locus ceruleus?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

25. Correct answer: B

Explanation:

Dexmedetomidine is a highly selective, and

potent alpha 2-adrenergic agonist

The pontine locus ceruleus has one of the

highest densities of alpha 2 receptors

Central alpha2-binding at presynaptic

neurons inhibits the release of

norepinephrine

It is well known that alpha 2 receptors are

coupled to Gi (G protein) and cause

suppression of cAMP levels

Quick tip: The elimination half-time of

dexmedetomidine approximately 2 hours

26. Which agent produces sedative effects by

stimulation of pre-synaptic alpha 2

adrenergic receptors?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

26. Correct answer: B

Explanation:

Dexmedetomidine is a highly selective and

potent alpha 2-adrenergic agonist

The pontine locus ceruleus has one of the

highest densities of alpha 2 receptors

Central alpha 2-binding at presynaptic

neurons inhibits the release of

norepinephrine

It is well known that alpha 2 receptors are

coupled to Gi (G protein) and cause

suppression of cAMP levels

Quick tip: Dexmedetomidine is an effective

treatment for nonthermally induced shivering

27. Which agent is MOST likely to cause

bradycardia and hypotension?

A) Propofol

B) Dexmedetomidine

C) Etomidate

D) Ketamine

27. Correct answer: B

Explanation:

Dexmedetomidine has sympatholytic actions

and may be accompanied by systemic

hypotension and bradycardia

Propofol produces decreases in systemic

blood pressure, but heart rate normally

remains unchanged. However, bradycardia

and asystole have rarely been observed with

propofol induction

At therapeutic doses, etomidate produces

minimal changes in heart rate

Ketamine generally produces cardiovascular

stimulation and increases in heart rate

Quick tip: Dexmedetomidine has been reported

to be effective at decreasing the postanesthetic

delirium effects of ketamine

28. Which agent has an anti-shivering effect?

A) Dexmedetomidine

B) Ketamine

C) Fentanyl

D) Etomidate

28. Correct answer: A

Explanation:

Dexmedetomidine is an effective treatment for

nonthermally induced shivering

Quick tip: The analgesic effects of

dexmedetomidine originate at the level of the

spinal cord

29. Which agent is LEAST likely to provide

reliable amnesia?

A) Propofol

B) Sevoflurane

C) Midazolam

D) Dexmedetomidine

29. Correct answer: D

Explanation:

From the options provided in this question,

dexmedetomidine is least likely to assure

amnesia. Dexmedetomidine administration generally results in a calm, easily arousable patient to full consciousness

Quick tip: Dexmedetomidine produces sedation

by decreasing sympathetic nervous system activity

30. Which agent does NOT have an imidazole

ring?

A) Propofol

B) Midazolam

C) Etomidate

D) Dexmedetomidine

30. Correct answer: A

Explanation:

Midazolam, ketamine, and dexmedetomidine

are imidazole compounds

Quick tip: Propofol is a substituted isopropylphenol

The imidazole nucleus renders the

drug water soluble at an acidic pH and lipid

soluble at physiologic pH

31. Which agent is NOT associated with

myoclonus?

A) Propofol

B) Methohexital

C) Etomidate

D) Dexmedetomidine

31. Correct answer: D

Explanation:

Propofol, etomidate, and methohexital are

associated with myoclonus activity

Dexmedetomidine can effectively prevent the

incidence of etomidate-induced myoclonus

Quick tip: Myoclonus seems to occur due to

disinhibition of subcortical structures that

generally suppress extrapyramidal motor activity

32. Which agent is least likely to produce an

isoelectric EEG?

A) Midazolam

B) Propofol

C) Thiopental

D) Isoflurane

32. Correct answer: A

Explanation:

Midazolam, in contrast to barbiturates and

propofol, is unable to produce an isoelectric

EEG

Isoflurane appears to cause burst suppression

at about 1.5 MAC, and electrical silence at 2

MAC

Quick tip: Midazolam is a potent anticonvulsant

33. Which is NOT an effect of intravenous

midazolam?

A) Anterograde amnesia

B) Anticonvulsant

C) Anxiolysis

D) Analgesia

33. Correct answer: D

Explanation:

Midazolam is a potent anticonvulsant

Midazolam is effective at producing sedation

and anxiolysis

Midazolam produces significant

ANTEROGRADE amnesia

Midazolam decreases anesthetics

requirements of volatile anesthetics, but does

NOT produce analgesia when administered

intravenously

Quick tip: Midazolam may be an effective

treatment for paradoxical vocal cord motion

34. Which agent antagonizes the actions of

benzodiazepines?

A) Flumazenil

B) Glucagon

C) N-acetylcysteine

D) Physostigmine

34. Correct answer: A

Explanation:

Flumazenil is a COMPETITIVE

benzodiazepine antagonist

The recommended initial dose is 0.2 mg IV

Quick tip: The duration of action of flumazenil is

30 to 60 minutes

35. Which inhaled anesthetic is classified as

an ether?

A) Halothane

B) Nitrous oxide

C) Sevoflurane

D) Xenon

35. Correct answer: C

Explanation:

Sevoflurane is a fluorinated methyl isopropyl

ETHER

Halothane is a halogenated ALKANE

derivative

Nitrous oxide is a colorless, odorless to sweet-

smelling INORGANIC gas

Xenon is an INERT gas with anesthetic

properties

Quick tip: Sevoflurane is nonpungent and

produces bronchodilation

36. Which inhaled anesthetic is classified as

an alkane?

A) Halothane

B) Nitrous oxide

C) Isoflurane

D) Desflurane

36. Correct answer: A

Explanation:

Halothane is a halogenated ALKANE

derivative

Nitrous oxide is a colorless, odorless to sweet-

smelling INORGANIC gas

Isoflurane, desflurane, and sevoflurane

are halogenated ETHERS

Quick tip: Halothane administration has been

associated with postoperative liver dysfunction

37. Which inhaled anesthetic requires a

heated vaporizer?

A) Sevoflurane

B) Nitrous oxide

C) Isoflurane

D) Desflurane

37. Correct answer: D

Explanation:

Desflurane can boil at normal operating room

temperature

Desflurane requires a heated and pressurized

vaporizer that needs an electrical power. This

creates an environment in which the agent has

a lower and more predictable volatility

Quick tip: Desflurane produces the highest

carbon monoxide concentrations in desiccated

CO2 absorbents

38. Which agent has a vapor pressure of 669

mmHg?

A) Sevoflurane

B) Desflurane

C) Isoflurane

D) Nitrous oxide

38. Correct answer: B

Explanation:

Desflurane has a vapor pressure near 1 atm

(669 mmHg) at 20 C

Quick tip: Desflurane is not suitable for

inhalational induction due to its pungency and

airway irritant effects

39. Which agent has been associated with the

toxic byproduct Compound A?

A) Sevoflurane

B) Desflurane

C) Isoflurane

D) Nitrous oxide

39. Correct answer: A

Explanation:

Compound A is nephrotoxic in rats, causing

renal proximal tubular injury

Compound A results from the interaction

between sevoflurane and the carbon dioxide

absorbent. This can occur with soda lime or

baralyme

What factors increase Compound A

production?

-Fresh absorbent

-Low fresh gas flows

-High concentrations of sevoflurane

-Higher absorbent temperatures

Quick tip: Isoflurane, desflurane, and

sevoflurane all prolong the electrocardiographic

QT interval

40. Which agent has a blood:gas coefficient

of 0.65?

A) Sevoflurane

B) Desflurane

C) Isoflurane

D) Nitrous oxide

40. Correct answer: A

Explanation:

Blood:gas coefficients of inhalational agents:

Sevoflurane 0.65

Desflurane 0.42

Nitrous oxide 0.47

Isoflurane 1.4

Quick tip: N2O increases cerebral blood flow

(CBF) with a mild increase in cerebral metabolic

rate of oxygen consumption (CMRO2)

.

41. Which agent has the lowest blood:gas

coefficient of 0.42?

A) Sevoflurane

B) Desflurane

C) Isoflurane

D) Nitrous oxide

41. Correct answer: B

Explanation:

Blood:gas coefficients of inhalational agents:

Sevoflurane 0.65

Desflurane 0.42

Nitrous oxide 0.47

Isoflurane 1.4

Quick tip: Volatile anesthetics decrease the

cerebral metabolic rate of oxygen consumption

(CMRO2)

42. Which agent undergoes the greatest

hepatic biotransformation?

A) Sevoflurane

B) Desflurane

C) Isoflurane

D) Nitrous oxide

42. Correct answer: A

Explanation:

All volatile anesthetics are biotransformed in

the liver to a variable extent

Sevoflurane 2-5%

Isoflurane 0.2%

Desflurane 0.02%

Halothane was not included in this questions,

but it undergoes oxidative metabolism of 15-

40%

Quick tip: Metabolism of sevoflurane leads to

release of inorganic fluoride

43. Which factor INCREASES FA/FI and

speeds onset of inhaled anesthetics?

A) Low alveolar ventilation

B) High agent solubility

C) Low functional residual capacity (FRC)

D) Low fresh gas flow

43. Correct answer: C

Explanation:

A low FRC will speed the onset of

inhalational induction. This is an anesthetic

implication during pregnancy. A reduction in

FRC results in a faster inhalational induction

and greater risk of hypoxemia.

All other factors provided decrease FA/FI and

slow onset of inhaled anesthetics

What other factors produce a rapid

inhalational induction?

-High minute ventilation

-High inspired partial pressure of anesthetic

-Low solubility of anesthetic in tissues

-Low cardiac output

-Low volume breathing circuit

Qu ick tip: Desflurane is the most pungent of the

inhaled anesthetics and can potentially cause

coughing, breath holding, sialorrhea, and

laryngospasm

44. Which factor DECREASES FA/FI and

slows onset of inhaled anesthetics?

A) Right to left intracardiac shunt

B) Low cardiac output

C) Low agent solubility

D) High fresh gas flow

44. Correct answer: A

Explanation:

A right to left shunt causes a dilutional effect

of shunted blood that is not mixed with

anesthetic. For test taking purposes, this slows

the rate of inhalational induction. However,

the clinical impact of this is negligible.

All other factors provided increase FA/FI and

speed onset of inhaled anesthetics

All of the inhaled anesthetics except

xenon are greenhouse gases. Global warming

effects are based on their infrared absorption and

atmospheric lifetimes

Quick tip: 

45. Which agent undergoes the LEAST

amount of metabolism?

A) Halothane

B) Sevoflurane

C) Isoflurane

D) Nitrous oxide

45. Correct answer: D

Explanation:

Nitrous oxide is the LEAST metabolized of

these agents

Nitrous oxide is metabolized by anaerobic

bacteria from the human intestine (0.004%)

All volatile anesthetics are biotransformed in

the liver to a variable extent

Sevoflurane 2-5%

Isoflurane 0.2%

Desflurane 0.02%

Halothane undergoes oxidative metabolism of

15-40%

Quick tip: Nitrous oxide (N2O) possesses good

analgesic properties

46. Nitrous oxide is ___________ more soluble

than nitrogen

A) 12 times

B) 24 times

C) 34 times

D) 50 times

46. Correct answer: C

Explanation:

Nitrous oxide is 34 times more soluble than

nitrogen in blood

What is the clinical implication of this?

Nitrous oxide can easily diffuse out of the

circulation and occupy air-filled

compartments

Think about intestinal gas, pneumothorax, air

embolism, middle ear, eyes, and cerebral

ventricles among others.

Quick tip: The presence of a closed

pneumothorax is a contraindication to nitrous

oxide administration

47. What is the minimum alveolar

concentration (MAC) of desflurane?

A) 1.2%

B) 2.2%

C) 6.6%

D) 10%

47. Correct answer: C

Explanation:

Solubility characteristics of desflurane include

blood:gas coefficient of 0.42 and potency

(MAC 6.6%)

Quick tip: MAC of anesthetic agents are additive

but not synergistic. For example, the combination

of 0.5 MAC of desflurane and 0.5 MAC of

sevoflurane is equivalent to 1 MAC

48. Which agent is the MOST potent?

A) Isoflurane

B) Desflurane

C) Sevoflurane

D) Nitrous oxide

Quick tip: 48. Correct answer: A

Explanation:

Isoflurane is the most potent of the agents on

this question.

Minimum alveolar concentration of inhaled

anesthetics:

Halothane 0.75

Isoflurane 1.17

Sevoflurane 1.8

Desflurane 6.6

Nitrous oxide 104

Isoflurane is an isomer of enflurane

and is highly pungent

49. Which factor INCREASES minimum

alveolar concentration (MAC) of

inhalational agents?

A) Hypernatremia

B) Hypothermia

C) Metabolic acidosis

D) Older age

49. Correct answer: A

Explanation:

Factors that increase MAC:

Acute use of cocaine, amphetamine, and

ephedrine

Chronic alcohol use
Hyperthermia and hypernatremia

Factors that decrease MAC:

Pregnancy, anemia, hyponatremia, hypoxia,

hypothermia, older age, acidosis

Concomitant administration of certain drugs:

Propofol, ketamine, etomidate, local

anesthetics, opioids, alpha 2 agonists,

benzodiazepines among others.

Quick tip: Administration of lithium and

verapamil decrease MAC

50. Which evoked potentials monitor the

corticospinal path?

A) SSEPs

B) MEPs

C) VEPs

D) BAEPs

50. Correct answer: B

Explanation:

Motor evoked potentials (MEPs) are used to

assess the integrity of the corticospinal tracts

during surgery

Quick tip: MEPs are used for intraoperative

monitoring (IOM) of the motor pathways

51. Which evoked potentials monitor the

dorsal column medial lemniscus path?

A) SSEPs

B) MEPs

C) VEPs

D) BAEPs

51. Correct answer: A

Explanation:

Somatosensory evoked potentials (SSEPs) are

used to monitor dorsal column integrity

Quick tip: Generally, a 50% decrease in

amplitude or a 10% increase in latency of SSEPs is

a warning signal

52. Local anesthetics are:

A) Strong bases

B) Weak bases

C) Strong acids

D) Weak acids

52. Correct answer: B

Explanation:

Local anesthetics are weak bases and have

pKa values above physiologic pH

Local anesthetics consist of a lipophilic and a

hydrophilic portion

Quick tip: Benzocaine is unique with a pKa of

3.5 (weak acid), so it exists most likely in the

nonionized form at physiologic pH

53. Which is NOT part of the local anesthetic

molecular structure?

A) Benzene ring

B) Intermediate chain (ester or amide)

C) Tertiary amine

D) Phenylpiperidine compound

53. Correct answer: D

Explanation:

Local anesthetics consist of a lipophilic and a

hydrophilic portion separated by a

hydrocarbon chain

The hydrophilic portion is usually a tertiary

amine

The lipophilic portion is usually an

unsaturated aromatic ring

An ester or an amide bond links the

hydrocarbon chain to the aromatic ring

Phenylpiperidines are a subclass of opioids

Quick tip: The two most important differences

among esters and amides are site of metabolism

and potential to produce allergic reactions

54. Which local anesthetic is metabolized by

pseudocholinesterase?

A) Chloroprocaine

B) Lidocaine

C) Ropivacaine

D) Mepivacaine

54. Correct answer: A

Explanation:

Ester local anesthetics such as chloroprocaine

undergo hydrolysis by plasma cholinesterase

(aka pseudocholinesterase)

Lidocaine, ropivacaine, and mepivacaine are

amide local anesthetics and undergo liver

metabolism by microsomal enzymes

Quick tip: Cocaine is metabolized by both plasma

and liver cholinesterases

55. Which local anesthetic is metabolized by

hepatic CYP450?

A) Benzocaine

B) Procaine

C) Tetracaine

D) Bupivacaine

55. Correct answer: D

Explanation:

Bupivacaine is an amide local anesthetic and

undergoes liver metabolism by microsomal

enzymes

Benzocaine, procaine, and tetracaine are ester

local anesthetics and undergo metabolism by

plasma cholinesterase

Quick tip: alpha 1-acid glycoprotein is the most

important plasma protein-binding site of

bupivacaine

56. Which local anesthetic has the MOST

protein binding?

A) Bupivacaine

B) Lidocaine

C) Mepivacaine

D) Tetracaine

56. Correct answer: A

Explanation:

Bupivacaine undergoes the most protein

biding from the agents on this questions

Protein binding of local anesthetics:

Bupivacaine 96%

Mepivacaine 78%

Tetracaine 76%

Lidocaine 65%

Quick tip: Chloroprocaine is thought to have the

lowest central nervous system and cardiovascular

toxicity of all currently used local anesthetics

57. Which local anesthetic has the LEAST

protein binding?

A) Ropivacaine

B) Lidocaine

C) Tetracaine

D) Chloroprocaine

57. Correct answer: D

Explanation:

Chloroprocaine has the lowest protein

binding of all clinically used local anesthetics

Quick tip: Epidurally administered

chloroprocaine can interfere with the action of

epidural opioids

58. Which local anesthetic has the highest

pKa of 8.7?

A) Chloroprocaine

B) Lidocaine

C) Bupivacaine

D) Mepivacaine

58. Correct answer: A

Explanation:

Chloroprocaine has the highest pKa of the

agents provided in this question

Rapid onset of chloroprocaine is not

associated with its pKa, but the use of high

concentrations due to low systemic toxicity

Quick tip: Addition of bicarbonate to local

anesthetics increases pH and favors the neutral

base form, speeding onset of action

59. Which is an ester-type local anesthetic?

A) Prilocaine

B) Mepivacaine

C) Tetracaine

D) Ropivacaine

59. Correct answer: C

Explanation:

The ester local anesthetics include tetracaine,

chloroprocaine, procaine, and cocaine

All other agents provided in this question are

amide local anesthetics

Quick tip: As a general rule, ester local

anesthetics will have one “i” and amides will have

two

60. Which of the following local anesthetics

can cause methemoglobinemia?

A) Mepivacaine

B) Benzocaine

C) Bupivacaine

D) Tetracaine

60. Correct answer: C

Explanation:

Methemoglobinemia can be a significant

problem after administration of benzocaine to

mucosal surfaces

Commonly used Cetacaine spray contains

benzocaine

Quick tip: Methylene blue is the treatment of

methemoglobinemia

61. Which local anesthetic has a pKa of 3.5

(lower than physiologic pH)?

A) Mepivacaine

B) Lidocaine

C) Benzocaine

D) Bupivacaine

61. Correct answer: C

Explanation:

Most local anesthetics have a pKa greater than

7.4 (physiologic pH). An exception is

benzocaine, which has a pKa of approximately

3.5. This makes benzocaine predominantly

nonionized at physiologic pH

Quick tip: Benzocaine is suited for topical

anesthesia of mucous membranes

62. Which local anesthetic is metabolized by

plasma pseudocholinesterase as well as

hepatic CYP450?

A) Bupivacaine

B) Lidocaine

C) Cocaine

D) Tetracaine

62. Correct answer: C

Explanation:

Cocaine is an ester type local anesthetic

metabolized by plasma and liver

cholinesterases

Quick tip: Cocaine has local anesthetic,

vasoconstrictive and sympathomimetic effects

63. Which modality is MOST likely to be

associated with local anesthetic systemic

toxicity (LAST)?

A) Spinal anesthesia

B) Epidural anesthesia

C) Peripheral nerve block

D) Topical anesthesia

63. Correct answer: C

Explanation:

Local anesthetic systemic toxicity (LAST)

occurs due to excessive plasma drug

concentration

Accidental intravascular injection of local

anesthetic drug during peripheral nerve block

anesthesia is the most common cause of

LAST

Quick tip: At the earliest sign of local anesthetic

toxicity, lipid emulsion is recommended

64. Which local anesthetic is MOST likely to

cause cardiac arrest from toxicity?

A) Bupivacaine

B) Lidocaine

C) Ropivacaine

D) Prilocaine

64. Correct answer: A

Explanation:

Bupivacaine is the most cardiotoxic agent

from this list.

Bupivacaine is considered a “fast in and slow

out” local anesthetic. Recovery from

bupivacaine blockade is prolonged during

diastole.

Quick tip: The more potent and lipophilic agents

are generally more cardiotoxic (bupivacaine,

tetracaine, etidocaine)

65. Which agent is the BEST option for

ventricular dysrhythmias in the setting of

local anesthetic systemic toxicity (LAST)?

A) Diltiazem

B) Amiodarone

C) Lidocaine

D) Procainamide

65. Correct answer: B

Explanation:

From these agents, amiodarone is the safest

option.

Calcium channel blockers such as diltiazem

should be avoided.

Lidocaine is a local anesthetic

Procainamide is a sodium channel blocker

Quick tip: During lipid emulsion therapy,

amiodarone may be sequestered with

unpredictable effects

66. Which is metabolized by the liver to O-

toluidine, which oxidizes hemoglobin

(Fe2+) to methemoglobin (Fe3+)?

A) Prilocaine

B) Mepivacaine

C) Tetracaine

D) Ropivacaine

66. Correct answer: A

Explanation:

A metabolite of prilocaine, O-toluidine, may

result in methemoglobinemia

It generally occurs at prilocaine doses greater

than 600 mg

O-toluidine is an oxidizing compound

(oxidizes hemoglobin to methemoglobin)

Quick tip: Benzocaine is another agent famous

for methemoglobinemia on exams J

67. Which additive can be combined with

local anesthetics to speed onset of action?

A) Epinephrine

B) Clonidine

C) Dexamethasone

D) Sodium bicarbonate

67. Correct answer: D

Explanation:

Alkalinization of local anesthetics speeds the

onset of action

Alkalinization with sodium bicarbonate

increases the lipid soluble form of local

anesthetic administered

Quick tip: Addition of epinephrine to lidocaine

prolongs the duration of action and decreases

systemic absorption

68. Which statement regarding

succinylcholine is INCORRECT?

A) Succinylcholine is a trigger agent for

malignant hyperthermia

B) Succinylcholine increases intragastric

pressure

C) Succinylcholine decreases lower

esophageal sphincter tone

D) Succinylcholine is two acetylcholine

molecules joined together

68. Correct answer: C

Explanation:

Administration of succinylcholine is

associated with an increase in intragastric and

lower esophageal sphincter pressures

Quick tip: Succinylcholine transiently

increases intraocular pressure

69. Which is an amide local anesthetic that

inhibits normal plasma cholinesterase?

A) Tetracaine

B) Lidocaine

C) Mepivacaine

D) Dibucaine

69. Correct answer: D

Explanation:

Dibucaine is mostly known for its ability to

inhibit normal plasma cholinesterase

Remember the test dibucaine number?

Quick tip: Atypical plasma cholinesterase is

responsible for the prolonged effects of drugs such

as succinylcholine and chloroprocaine

70. Which agent undergoes Hofmann

elimination?

A) Succinylcholine

B) Rocuronium

C) Cisatracurium

D) Vecuronium

70. Correct answer: C

Explanation:

Cisatracurium is an isomer of atracurium

Cisatracurium is metabolized by Hofmann

elimination to laudanosine and

monoquaternary alcohol metabolite

Quick tip: Hofmann elimination is dependent on

the pH and temperature of plasma

71. Which non-depolarizing neuromuscular

blocking agent is metabolized by

pseudocholinesterase?

A) Mivacurium

B) Atracurium

C) Cisatracurium

D) Succinylcholine

71. Correct answer: A

Explanation:

Mivacurium’s clearance is dependent on the

enzyme plasma cholinesterase

Quick tip: Mivacurium is associated with

histamine release L

72. Which neuromuscular blocking agent

produces metabolite laudanosine?

A) Succinylcholine

B) Rocuronium

C) Cisatracurium

D) Vecuronium

72. Correct answer: C

Explanation:

Cisatracurium is an isomer of atracurium

Cisatracurium is metabolized by Hofmann

elimination to laudanosine and

monoquaternary alcohol metabolite

Quick tip: Cisatracurium does not invoke

histamine release

73. Which of the following statements is

CORRECT regarding Hofmann

elimination?

A) Reaction occurs faster with acidosis and

hypothermia

B) Reaction occurs slower with alkalosis and

hyperthermia

C) Reaction occurs faster with alkalosis and

hypothermia

D) Reaction occurs slower with acidosis and

hypothermia

73. Correct answer: D

Explanation:

Hofmann elimination is dependent on the pH

and temperature of plasma

Hofmann elimination is slowed by acidosis

and hypothermia

Quick tip: Hofmann elimination is an organ-

independent elimination process. It is appropriate

for the renally and hepatically compromised

patients

74. Which agent undergoes the GREATEST

amount of renal elimination?

A) Rocuronium

B) Vecuronium

C) Cisatracurium

D) Pancuronium

74. Correct answer: D

Explanation:

Pancuronium is a potent and long-acting

neuromuscular blocker

Approximately 40-60% of pancuronium is

cleared by the kidney

Quick tip: Pancuronium has vagolytic effects and

it also inhibits plasma cholinesterase L

75. Which of the following factors

ANTAGONIZES nondepolarizing

neuromuscular blockers?

A) Aminoglycosides

B) Magnesium

C) Burns

D) Hypothermia

75. Correct answer: C

Explanation:

It is important to know which factors increase

the potency and which factors antagonize

nondepolarizing neuromuscular blockers

Factors that potentiate nondepolarizers:

-Inhalational anesthetics

-Aminoglycoside antibiotics

-Hypothermia

-Magnesium sulfate

-Most local anesthetics

Factors that antagonize nondepolarizers:

-Chronic anticonvulsant therapy

-Hyperparathyroidism

-Hypercalcemia

-Burns

There are many more factors.

Please familiarize yourself with these J

Quick tip: Clindamycin inhibits the prejunctional

release of acetylcholine and can potentiate

nondepolarizing neuromuscular blockers

76. Which of the following factors

POTENTIATES nondepolarizing

neuromuscular blockade?

A) Respiratory acidosis

B) Carbamazepine

C) Epinephrine

D) Corticosteroids

76. Correct answer: A

Explanation:

Respiratory acidosis potentiates the blockade

of most nondepolarizing neuromuscular

blockers and antagonizes reversal

Carbamazepine, epinephrine, and

corticosteroids antagonize neuromuscular

blockade

There are many more factors.

Please familiarize yourself with these J

Quick tip: Hypothermia prolongs blockade by

decreasing metabolism

77. Which of the following factors

ANTAGONIZES nondepolarizing

neuromuscular blockade?

A) Clindamycin

B) Sevoflurane

C) Furosemide

D) Hypercalcemia

77. Correct answer: D

Explanation:

It is important to know which factors increase

the potency and which factors antagonize

nondepolarizing neuromuscular blockers

Factors that potentiate nondepolarizers:

-Inhalational anesthetics

-Aminoglycoside antibiotics

-Hypothermia

-Magnesium sulfate

-Most local anesthetics

Factors that antagonize nondepolarizers:

-Chronic anticonvulsant therapy

-Hyperparathyroidism

-Hypercalcemia

-Burns

Quick tip: Hypocalcemia and hypokalemia

augment a nondepolarizing block

78. Which of the following factors

POTENTIATES nondepolarizing

neuromuscular blockade?

A) Norepinephrine

B) Hypermagnesemia

C) Theophylline

D) Alkalosis

78. Correct answer: B

Explanation:

Hypermagnesemia may be seen in

preeclamptic patients managed with

magnesium sulfate.

Magnesium competes with calcium and

potentiates nondepolarizing neuromuscular

blockade

Quick tip: Neonates have increased sensitivity to

nondepolarizing relaxants due to their immature

neuromuscular junctions

79. Which agent has a vagolytic effect and

stimulates release of catecholamines?

A) Cisatracurium

B) Vecuronium

C) Pancuronium

D) Succinylcholine

79. Correct answer: C

Explanation:

Pancuronium produces vagal blockade

(vagolytic effect) and sympathetic stimulation

How does pancuronium produce tachycardia

and hypertension?

-Ganglionic stimulation

-Decreased catecholamine reuptake

-Catecholamine release from adrenergic nerve

endings

Quick tip: Patients allergic to bromides may

exhibit reactions (pancuronium bromide) L

80. Which is a tertiary amine and crosses the

blood brain barrier (BBB)?

A) Edrophonium

B) Neostigmine

C) Pyridostigmine

D) Physostigmine

80. Correct answer: D

Explanation:

Physostigmine is tertiary amine and lipid

soluble. This means it freely passes the blood

brain barrier

All other agents are quaternary amines

Physostigmine is effective as treatment for

central anticholinergic toxicity from

scopolamine or atropine overdose

Quick tip: Physostigmine has shown to be

effective in preventing postoperative shivering J

81. Which of the following agents has anti-

shivering properties?

A) Dexmedetomidine

B) Morphine

C) Glycopyrolate

D) Neostigmine

81. Correct answer: A

Explanation:

Dexmedetodmine is effective for postoperativshivering

Quick tip: Dexmedetomidine can promote

perioperative hypothermia L

82. Which is NOT a side effect of

neostigmine?

A) Bradycardia

B) Increased salivation

C) Bronchodilation

D) Miosis

82. Correct answer: C

Explanation:

Neostigmine inhibits acetylcholinesterase

Muscarinic side effects of neostigmine

administration include: bradyarrhythmias, bronchoconstriction, increased secretions,

miosis, and increased peristalsis

Quick tip: Concomitant administration of

anticholinergic agent with neostigmine minimizes

muscarinic side effects

83. All of these are side effects of

neostigmine EXCEPT:

A) Bronchoconstriction

B) Constipation

C) Increased secretions

D) Nausea

83. Correct answer: B

Explanation:

Neostigmine inhibits acetylcholinesterase

Muscarinic side effects of neostigmine

administration include: bradyarrhythmias,

bronchoconstriction, increased secretions,

miosis, and increased peristalsis

Quick tip: Neostigmine is a quaternary

ammonium, lipid insoluble molecule. It cannot

pass the blood brain barrier

84. Which agent increases heart rate the

MOST?

A) Atropine

B) Glycopyrolate

C) Scopolamine

D) Milrinone

84. Correct answer: A

Explanation:

Atropine causes the most tachycardia from

these agents

Quick tip: Small atropine doses (<0.4 mg) have

been associated with a paradoxical transient

slowing of the heart rate

85. Which agent may decrease the

effectiveness of hormonal contraceptive

(birth control) for up to 7 days?

A) Neostigmine

B) Sugammadex

C) Metoclopramide

D) Cisatracurium

85. Correct answer: B

Explanation:

Sugammadex is a modified cyclodextrin

molecule

Hormonal contraceptive structures with

steroidal structure are impaired by

sugammadex for approximately 7 days

Nonhormonal contraceptives should be used

for 7 days after its administration

Quick tip: Sugammadex is mainly eliminated by

the kidneys

86. Which of the following statements is

INCORRECT about succinylcholine?

A) It is a quaternary ammonium compound

B) It is two molecules of acetylcholine linked

together

C) It is metabolized predominantly by

acetylcholinesterase

D) Succinylcholine’s neuromuscular block

can be potentiated by administration of

neostigmine

86. Correct answer: C

Explanation:

Succinylcholine is NOT metabolized by

acetylcholinesterase

Succinylcholine is metabolized by plasma

cholinesterase (pseudocholinesterase)

Quick tip: Cholinesterase inhibitors can prolong

blockade of succinylcholine

87. Which of the following statements is

INCORRECT about succinylcholine?

A) Succinylcholine produces muscarinic as

well as nicotinic effects

B) Decreases intragastric pressure

C) Causes transient increased intraocular

pressure

D) Normally causes muscle fasciculations

87. Correct answer: B

Explanation:

Administration of succinylcholine is

associated with an increase in intragastric and

lower esophageal sphincter pressures

Quick tip: Metoclopramide reduces

pseudocholinesterase activity

88. Which drug slightly INHIBITS plasma

cholinesterase and may increase duration

of action of succinylcholine?

A) Pancuronium

B) Rocuronium

C) Vecuronium

D) Cisatracurium

88. Correct answer: A

Explanation:

Drugs known to decrease

pseudocholinesterase activity:

-Echothiophate

-Neostigmine

-Phenelzine

-Cyclophosphamide

-Metoclopramide

-Esmolol

-Pancuronium

-Oral contraceptives

Quick tip: Echothiophate is an organophosphate

used for glaucoma

89. Which agent is LEAST likely to cause

anaphylactic reaction?

A) Atracurium

B) Mivacurium

C) Succinylcholine

D) Cisatracurium

89. Correct answer: D

Explanation:

Succinylcholine, atracurium, and mivacurium

are associated with histamine release

Cisatracurium does not invoke histamine

release

Quick tip: Mivacurium is a short-acting,

benzylisoquinoline, nondepolarizing

neuromuscular blocker

90. What electrolyte disturbance is likely to

POTENTIATE neuromuscular blocking

agents?

A) Hypokalemia

B) Hypercalcemia

C) Hypernatremia

D) Hypomagnesemia

90. Correct answer: A

Explanation:

Hypocalcemia and hypokalemia augment a

nondepolarizing block

It is important to know which factors increase

the potency and which factors antagonize

nondepolarizing neuromuscular blockers

Factors that potentiate nondepolarizers:

-Inhalational anesthetics

-Aminoglycoside antibiotics

-Hypothermia

-Magnesium sulfate

-Most local anesthetics

Factors that antagonize nondepolarizers:

-Chronic anticonvulsant therapy

-Hyperparathyroidism

-Hypercalcemia

-Burns

Quick tip: Succinylcholine and mivacurium are

metabolized by plasma cholinesterase

91. Which of the following is a side effect of

neostigmine?

A) Anhidrosis

B) Xerostomia

C) Mydriasis

D) Increased peristalsis

91. Correct answer: D

Explanation:

Neostigmine inhibits acetylcholinesterase

Muscarinic side effects of neostigmine

administration include: bradyarrhythmias,

bronchoconstriction, increased secretions,

miosis, and increased peristalsis

Quick tip: Neostigmine is used for treatment of

non-obstructive ileus

92. Which opioid is the MOST potent?

A) Alfentanil

B) Sufentanil

C) Remifentanil

D) Fentanyl

92. Correct answer: B

Explanation:

The most potent opioid among these agents is

sufentanil

Sufentanil is 5 to 10 time as potent as fentanyl

Fentanyl is approximately 50 to 100 times

as potent as morphine

Quick tip: Sufentanil is a thienyl analogue of

fentanyl

93. Which opioid is the LEAST potent?

A) Morphine

B) Hydromorphone

C) Meperidine

D) Alfentanil

93. Correct answer: C

Explanation:

The least potent opioid among these agents is

meperidine

Meperidine is 1/10th as potent as morphine

It is derived from phenylpiperidine

Quick tip: Meperidine shares similar structural

features to local anesthetics

94. Which opioid is structurally like

atropine?

A) Morphine

B) Hydromorphone

C) Alfentanil

D) Meperidine

94. Correct answer: D

Explanation:

Structurally, meperidine is similar to atropine. Meperidine is likely to increase heart rate

Quick tip: Large doses of meperidine result in

decreased myocardial contractility

95. Which of the following opioids is

chemically related to meperidine, a

phenylpiperidine derivative?

A) Codeine

B) Hydrocodone

C) Oxycodone

D) Fentanyl

95. Correct answer: D

Explanation:

Fentanyl is a phenylpiperidine derivative

structurally related to meperidine

Quick tip: An estimated 75% of initial fentanyl

dose undergoes first-pass pulmonary uptake

96. Which opioid is MOST unionized at

physiologic pH?

A) Morphine

B) Fentanyl

C) Alfentanil

D) Sufentanil

96. Correct answer: C

Explanation:

Alfentanil has a low pKa and nearly 90% of

administered drug will be in its nonionized

form at physiologic pH

It is the nonionized fraction of the drug that

crosses the blood brain barrier

Quick tip: Erythromycin inhibits the metabolism

of alfentanil and prolongs its effects

97. Which is NOT a common side effect of

opioids?

A) Decreased biliary pressure

B) Miosis

C) Delayed gastric emptying

D) Bradycardia

97. Correct answer: A

Explanation:

Opioids increase biliary pressure

Gastrointestinal opioid side effects include

spasm of biliary smooth muscle, biliary

colic, constipation, and delayed gastric

emptying

Quick tip: Opium was used to treat diarrhea

before its analgesic use was popularized J

98. Which is a common side effect of opioids?

A) Vasoconstriction

B) Pruritus

C) Diuresis

D) Increased cellular immunity

98. Correct answer: B

Explanation:

Generally, opioids cause vasodilation,

pruritus, urinary retention, and decreased

cellular immunity

Quick tip : Paradoxically, sufentanil, fentanyl,

and alfentanil may be associated with reflex

coughing

99. Metabolism of this opioid is completely

unrelated to hepatic clearance

mechanisms

A) Fentanyl

B) Alfentanil

C) Sufentanil

D) Remifentanil

99. Correct answer: D

Explanation:

Remifentanil has an ester structure that

renders it susceptible to ester hydrolysis by

nonspecific and tissue esterases

Remifentanil metabolism is unchanged in

renal and hepatic failure

Quick tip : Independent of duration of infusion,

remifentanil’s context sensitive half-time is

approximately 4 minutes

100. Which opioid has a metabolite that

has analgesic and excitatory central

nervous system properties? Effects from

this metabolite range from anxiety and

tremors to myoclonus and franks seizures

A) Morphine

B) Meperidine

C) Alfentanil

D) Fentanyl

100. Correct answer: B

Explanation:

Normeperidine may produce myoclonus and

seizures (CNS stimulation)

Normeperidine may also be associated with

delirium (confusion and hallucinations)

Quick tip : Normeperidine has an elimination

half-time of 15 hours