Relias Dysrhythmia Basic Exam B Study Guide with
Actual Complete Questions, Correct Verified
Answers and Detailed Rationales Already Graded
A+ | 2026 Updated
Master your credentialing with this comprehensive study guide for the Relias Dysrhythmia
Basic Exam B (2025/2026). This resource features verified practice questions, annotated
rhythm breakdowns, and precise clinical Rationales. Key topics include PR/QRS intervals,
AV blocks (Wenckebach vs. Mobitz II), lethal arrhythmias (V-Fib, PEA), and standard ACLS
intervention protocols. Perfect for telemetry, ICU, and emergency nurses seeking to pass
their competency exam on the first attempt.
,1. Which of the following cardiac rhythms is characterized by a progressively lengthening
PR interval followed by a dropped QRS complex?
A) First-Degree AV Block
B) Second-Degree AV Block, Type II (Mobitz II)
C) Second-Degree AV Block, Type I (Wenckebach)
D) Third-Degree AV Block (Complete Heart Block)
Rationale: Second-Degree AV Block, Type I (Wenckebach) is defined by a progressive
elongation of the PR interval from beat to beat until an atrial impulse fails to conduct
to the ventricles, resulting in a dropped QRS complex.
2. A patient's monitor shows a chaotic, wavy baseline with no identifiable P waves, QRS
complexes, or T waves. The patient is unresponsive and pulseless. What is the
immediate priority action?
A) Administer a 150 mg IV bolus of Amiodarone
B) Start high-quality CPR while preparing to defibrillate
C) Perform immediate synchronized cardioversion
D) Prepare for transcutaneous pacing
Rationale: Ventricular Fibrillation (V-Fib) is a lethal, pulseless rhythm. The immediate
treatment priority is to begin high-quality chest compressions and defibrillate the
patient as soon as a shock is available.
3. What is the normal duration of a PR interval in an adult ECG?
A) 0.12 to 0.20 seconds
B) 0.04 to 0.10 seconds
C) 0.20 to 0.40 seconds
D) 0.35 to 0.44 seconds
Rationale: A normal PR interval represents the time it takes for an electrical impulse to
travel from the SA node through the AV node, measuring between 0.12 and 0.20
seconds (3 to 5 small boxes).
4. A patient's ECG displays regular P waves and regular QRS complexes, but there is no
relationship or correlation between them. The PR intervals are completely variable.
Which rhythm does this describe?
A) First-Degree AV Block
B) Second-Degree AV Block, Type I
C) Second-Degree AV Block, Type II
D) Third-Degree AV Block (Complete Heart Block)
Rationale: Third-Degree AV Block involves a complete dissociation between the atria
, and ventricles. The P-P and R-R intervals are regular, but they beat independently of
one another.
5. Which of the following rhythms requires immediate unsynchronized defibrillation?
A) Stable Ventricular Tachycardia with a pulse
B) Atrial Fibrillation with Rapid Ventricular Response
C) Pulseless Ventricular Tachycardia
D) Asystole
Rationale: Pulseless Ventricular Tachycardia is a shockable arrest rhythm treated
identically to Ventricular Fibrillation with immediate, unsynchronized defibrillation.
6. What is the maximum normal width of a healthy QRS complex?
A) 0.04 seconds
B) Less than 0.12 seconds
C) 0.20 seconds
D) 0.16 seconds
Rationale: A normal, narrow QRS complex is less than 0.12 seconds (under 3 small
boxes), indicating that ventricular depolarization is occurring rapidly via the normal
conduction pathway.
7. A patient presents with an irregular heart rhythm, a heart rate of 120 bpm, and a total
absence of P waves, replaced instead by fine, chaotic baseline fibrillatory lines. This
rhythm is:
A) Atrial Fibrillation
B) Atrial Flutter
C) Sinus Arrhythmia
D) Junctional Tachycardia
Rationale: Atrial Fibrillation is distinguished by its "irregularly irregular" ventricular
rhythm and the absence of discrete P waves, which are replaced by rapid, chaotic
fibrillatory activity.
8. Which drug is the primary first-line vasopressor administered during a pulseless cardiac
arrest algorithm?
A) Adenosine
B) Atropine
C) Epinephrine
D) Amiodarone
Rationale: Epinephrine 1 mg IV/IO is the standard first-line vasopressor given every 3
to 5 minutes during cardiac arrest to optimize coronary and cerebral perfusion
pressure.
Actual Complete Questions, Correct Verified
Answers and Detailed Rationales Already Graded
A+ | 2026 Updated
Master your credentialing with this comprehensive study guide for the Relias Dysrhythmia
Basic Exam B (2025/2026). This resource features verified practice questions, annotated
rhythm breakdowns, and precise clinical Rationales. Key topics include PR/QRS intervals,
AV blocks (Wenckebach vs. Mobitz II), lethal arrhythmias (V-Fib, PEA), and standard ACLS
intervention protocols. Perfect for telemetry, ICU, and emergency nurses seeking to pass
their competency exam on the first attempt.
,1. Which of the following cardiac rhythms is characterized by a progressively lengthening
PR interval followed by a dropped QRS complex?
A) First-Degree AV Block
B) Second-Degree AV Block, Type II (Mobitz II)
C) Second-Degree AV Block, Type I (Wenckebach)
D) Third-Degree AV Block (Complete Heart Block)
Rationale: Second-Degree AV Block, Type I (Wenckebach) is defined by a progressive
elongation of the PR interval from beat to beat until an atrial impulse fails to conduct
to the ventricles, resulting in a dropped QRS complex.
2. A patient's monitor shows a chaotic, wavy baseline with no identifiable P waves, QRS
complexes, or T waves. The patient is unresponsive and pulseless. What is the
immediate priority action?
A) Administer a 150 mg IV bolus of Amiodarone
B) Start high-quality CPR while preparing to defibrillate
C) Perform immediate synchronized cardioversion
D) Prepare for transcutaneous pacing
Rationale: Ventricular Fibrillation (V-Fib) is a lethal, pulseless rhythm. The immediate
treatment priority is to begin high-quality chest compressions and defibrillate the
patient as soon as a shock is available.
3. What is the normal duration of a PR interval in an adult ECG?
A) 0.12 to 0.20 seconds
B) 0.04 to 0.10 seconds
C) 0.20 to 0.40 seconds
D) 0.35 to 0.44 seconds
Rationale: A normal PR interval represents the time it takes for an electrical impulse to
travel from the SA node through the AV node, measuring between 0.12 and 0.20
seconds (3 to 5 small boxes).
4. A patient's ECG displays regular P waves and regular QRS complexes, but there is no
relationship or correlation between them. The PR intervals are completely variable.
Which rhythm does this describe?
A) First-Degree AV Block
B) Second-Degree AV Block, Type I
C) Second-Degree AV Block, Type II
D) Third-Degree AV Block (Complete Heart Block)
Rationale: Third-Degree AV Block involves a complete dissociation between the atria
, and ventricles. The P-P and R-R intervals are regular, but they beat independently of
one another.
5. Which of the following rhythms requires immediate unsynchronized defibrillation?
A) Stable Ventricular Tachycardia with a pulse
B) Atrial Fibrillation with Rapid Ventricular Response
C) Pulseless Ventricular Tachycardia
D) Asystole
Rationale: Pulseless Ventricular Tachycardia is a shockable arrest rhythm treated
identically to Ventricular Fibrillation with immediate, unsynchronized defibrillation.
6. What is the maximum normal width of a healthy QRS complex?
A) 0.04 seconds
B) Less than 0.12 seconds
C) 0.20 seconds
D) 0.16 seconds
Rationale: A normal, narrow QRS complex is less than 0.12 seconds (under 3 small
boxes), indicating that ventricular depolarization is occurring rapidly via the normal
conduction pathway.
7. A patient presents with an irregular heart rhythm, a heart rate of 120 bpm, and a total
absence of P waves, replaced instead by fine, chaotic baseline fibrillatory lines. This
rhythm is:
A) Atrial Fibrillation
B) Atrial Flutter
C) Sinus Arrhythmia
D) Junctional Tachycardia
Rationale: Atrial Fibrillation is distinguished by its "irregularly irregular" ventricular
rhythm and the absence of discrete P waves, which are replaced by rapid, chaotic
fibrillatory activity.
8. Which drug is the primary first-line vasopressor administered during a pulseless cardiac
arrest algorithm?
A) Adenosine
B) Atropine
C) Epinephrine
D) Amiodarone
Rationale: Epinephrine 1 mg IV/IO is the standard first-line vasopressor given every 3
to 5 minutes during cardiac arrest to optimize coronary and cerebral perfusion
pressure.
