Chapter 11 Antiarrhythmics
1. A patient with a history of atrial fibrillation has had a worsening of his or her condition.
The nurse knows that the drug of choice for long-term stabilization of atrial fibrillation
following electrocardioversion is what?
A) Disopyramide (Norpace)
B) Moricizine (Ethmozine)
C) Procainamide (Pronestyl)
D) Quinidine (generic)
Ans D
Feedback
Quinidine is often the drug of choice for long-term stabilization of atrial fibrillation after
the rhythm is converted by electrocardioversion. Quinidine is a class I antiarrhythmic
and stabilizes the cell membrane by binding to sodium channels, depressing phase 0 of
the action potential, and changing the duration of the action potential. Disopyramide,
moricizine, and procainamide are all used in the treatment of life-threatening ventricular
arrhythmias.
2. What class of antiarrhythmics drug blocks potassium channels, prolonging phase 3 of the
action potential and slowing the rate and conduction of the heart?
A) I
B) II
C) III
D) IV
Ans C
Feedback
The class III antiarrhythmics block potassium, prolonging phase 3 of the action potential,
which prolongs repolarization and slows the rate and conduction of the heart. Class I
drugs block the sodium channels in the cell membrane during an action potential. Class
II drugs are beta-adrenergic blockers that block beta-receptors, causing a depression of
phase 4 of the action potential. Class IV drugs block calcium channels in the cell
membrane leading to a depression of depolarization and a prolongation of phases I and II
of repolarization, which slows automaticity.
, 3. The nurse is caring for a pediatric patient who has been diagnosed with paroxysmal atrial
tachycardia. The order reads digoxin 10 mcg/kg orally. The child weighs 44 pounds.
How many mcg will the nurse administer?
A) 50 mcg
B) 100 mcg
C) 150 mcg
D) 200 mcg
Ans D
Feedback
The nurse will administer 200 mcg. (2.2 pounds 1 kg = X 20 kg, 20(10) = 200 mcg).
4. The nurse is providing drug teaching about quinidine in preparation for the patients
discharge. The nurse discusses drugfood interactions and advises the patient to
drink what?
A) Apple juice
B) Grapefruit juice
C) Milk
D) Orange juice
Ans A
Feedback
Apple juice would be the best choice. Quinidine requires a slightly acidic urine (normal
state) for excretion. Patients receiving quinidine should avoid foods that alkalinize the
urine (e.g., citrus juices, vegetables, antacids, milk products), which could lead to
increased quinidine levels and toxicity. Grapefruit juice has been shown to interfere with
the metabolism of quinidine, leading to increased serum levels and toxic effects; this
combination should be avoided.
5. A patient has had sotalol (Betapace) ordered for treatment of a ventricular arrhythmia.
What will the nurse consider when administering the drug?
A) Sotalol has a very short duration of action
B) Food increases the bioavailability of the drug
C) Absorption of sotalol is decreased by the presence of food
D) The drug is best administered intramuscularly
, Ans C
Feedback
This drug should not be taken with food because absorption is decreased. The drug
should be given 1 hour before or 2 hours after a meal. Adenosine, not sotalol, has a very
short duration of action and food increases the bioavailability of propranolol. Sotalol is
administered by oral route only.
6. The nurse is caring for a patient who reports insomnia since starting the antiarrhythmic
agent prescribed for him or her. What antiarrhythmic agent would the nurse expect this
patient is taking?
A) Disopyramide (Norpace)
B) Amiodarone (Cordarone)
C) Procainamide (Pronestyl)
D) Propranolol (Inderal)
Ans D
Feedback
Class II antiarrhythmics can cause insomnia. The adverse effects associated with class
II antiarrhythmics are related to the effects of blocking beta-receptors in the
sympathetic nervous system. CNS effects include dizziness, insomnia, unusual dreams,
and fatigue.
Disopyramide and procainamide are class I agents and do not cause insomnia.
Amiodarone is a class III drug and is not associated with insomnia.
7. A patient with impaired renal function is to receive dofetilide (Tikosyn) for conversion of
atrial fibrillation. What is the nurses priority assessment before administering the drug? A)
Check the patients creatinine level.
B) Measure the urine output.
C) Listen to breath sounds.
D) Measure the PR interval on the electrocardiogram.
Ans A
Feedback
When giving dofetilide to a patient with renal dysfunction, the dosage must be
calculated according to the patients creatinine level to ensure the therapeutic effect
while limiting toxicity. This drug can only be administered by oral route. Intake and
output as well as breath sounds may need to be assessed but are not related to
1. A patient with a history of atrial fibrillation has had a worsening of his or her condition.
The nurse knows that the drug of choice for long-term stabilization of atrial fibrillation
following electrocardioversion is what?
A) Disopyramide (Norpace)
B) Moricizine (Ethmozine)
C) Procainamide (Pronestyl)
D) Quinidine (generic)
Ans D
Feedback
Quinidine is often the drug of choice for long-term stabilization of atrial fibrillation after
the rhythm is converted by electrocardioversion. Quinidine is a class I antiarrhythmic
and stabilizes the cell membrane by binding to sodium channels, depressing phase 0 of
the action potential, and changing the duration of the action potential. Disopyramide,
moricizine, and procainamide are all used in the treatment of life-threatening ventricular
arrhythmias.
2. What class of antiarrhythmics drug blocks potassium channels, prolonging phase 3 of the
action potential and slowing the rate and conduction of the heart?
A) I
B) II
C) III
D) IV
Ans C
Feedback
The class III antiarrhythmics block potassium, prolonging phase 3 of the action potential,
which prolongs repolarization and slows the rate and conduction of the heart. Class I
drugs block the sodium channels in the cell membrane during an action potential. Class
II drugs are beta-adrenergic blockers that block beta-receptors, causing a depression of
phase 4 of the action potential. Class IV drugs block calcium channels in the cell
membrane leading to a depression of depolarization and a prolongation of phases I and II
of repolarization, which slows automaticity.
, 3. The nurse is caring for a pediatric patient who has been diagnosed with paroxysmal atrial
tachycardia. The order reads digoxin 10 mcg/kg orally. The child weighs 44 pounds.
How many mcg will the nurse administer?
A) 50 mcg
B) 100 mcg
C) 150 mcg
D) 200 mcg
Ans D
Feedback
The nurse will administer 200 mcg. (2.2 pounds 1 kg = X 20 kg, 20(10) = 200 mcg).
4. The nurse is providing drug teaching about quinidine in preparation for the patients
discharge. The nurse discusses drugfood interactions and advises the patient to
drink what?
A) Apple juice
B) Grapefruit juice
C) Milk
D) Orange juice
Ans A
Feedback
Apple juice would be the best choice. Quinidine requires a slightly acidic urine (normal
state) for excretion. Patients receiving quinidine should avoid foods that alkalinize the
urine (e.g., citrus juices, vegetables, antacids, milk products), which could lead to
increased quinidine levels and toxicity. Grapefruit juice has been shown to interfere with
the metabolism of quinidine, leading to increased serum levels and toxic effects; this
combination should be avoided.
5. A patient has had sotalol (Betapace) ordered for treatment of a ventricular arrhythmia.
What will the nurse consider when administering the drug?
A) Sotalol has a very short duration of action
B) Food increases the bioavailability of the drug
C) Absorption of sotalol is decreased by the presence of food
D) The drug is best administered intramuscularly
, Ans C
Feedback
This drug should not be taken with food because absorption is decreased. The drug
should be given 1 hour before or 2 hours after a meal. Adenosine, not sotalol, has a very
short duration of action and food increases the bioavailability of propranolol. Sotalol is
administered by oral route only.
6. The nurse is caring for a patient who reports insomnia since starting the antiarrhythmic
agent prescribed for him or her. What antiarrhythmic agent would the nurse expect this
patient is taking?
A) Disopyramide (Norpace)
B) Amiodarone (Cordarone)
C) Procainamide (Pronestyl)
D) Propranolol (Inderal)
Ans D
Feedback
Class II antiarrhythmics can cause insomnia. The adverse effects associated with class
II antiarrhythmics are related to the effects of blocking beta-receptors in the
sympathetic nervous system. CNS effects include dizziness, insomnia, unusual dreams,
and fatigue.
Disopyramide and procainamide are class I agents and do not cause insomnia.
Amiodarone is a class III drug and is not associated with insomnia.
7. A patient with impaired renal function is to receive dofetilide (Tikosyn) for conversion of
atrial fibrillation. What is the nurses priority assessment before administering the drug? A)
Check the patients creatinine level.
B) Measure the urine output.
C) Listen to breath sounds.
D) Measure the PR interval on the electrocardiogram.
Ans A
Feedback
When giving dofetilide to a patient with renal dysfunction, the dosage must be
calculated according to the patients creatinine level to ensure the therapeutic effect
while limiting toxicity. This drug can only be administered by oral route. Intake and
output as well as breath sounds may need to be assessed but are not related to