,NSG 223 Exam 1 Medical-Surgical Nursing II Questions And Answers
2026/2027 Herzing University
Q1. Which component of an ECG represents ventricular depolarization?
A) P wave
B) PR interval
C) QRS complex
D) T wave
Correct Answer: C) QRS complex
Rationale: The QRS complex represents ventricular depolarization, which
initiates ventricular contraction.
Q2. Which ECG component represents atrial depolarization?
A) P wave
B) QRS complex
C) ST segment
D) T wave
Correct Answer: A) P wave
Rationale: The P wave represents electrical activation of the atria.
Q3. Which interval reflects the time from the beginning of atrial
depolarization through conduction to the ventricles?
A) QT interval
B) PR interval
C) ST segment
D) QRS interval
Correct Answer: B) PR interval
Rationale: The PR interval represents conduction from the atria through the
AV node and His-Purkinje system to the ventricles.
Q4. What is the expected normal PR interval?
A) 0.02–0.04 seconds
B) 0.06–0.10 seconds
C) 0.12–0.20 seconds
D) 0.24–0.30 seconds
Correct Answer: C) 0.12–0.20 seconds
Rationale: A normal PR interval is generally 0.12 to 0.20 seconds.
Q5. What does the QT interval represent?
A) Atrial depolarization only
B) Ventricular depolarization and repolarization
C) AV-node conduction only
, D) Atrial repolarization only
Correct Answer: B) Ventricular depolarization and repolarization
Rationale: The QT interval encompasses ventricular electrical activation
and recovery.
Q6. Which action should the nurse take when preparing a client for ECG
monitoring?
A) Place electrodes over clean, dry skin.
B) Place electrodes over clothing.
C) Apply electrodes over excessive lotion.
D) Place electrodes over thick hair without preparation.
Correct Answer: A) Place electrodes over clean, dry skin.
Rationale: Clean, dry skin improves electrode contact and reduces artifact.
Q7. A client has a regular rhythm with a rate of 78/min, a P wave before
every QRS complex, and a constant PR interval. Which rhythm is present?
A) Atrial fibrillation
B) Normal sinus rhythm
C) Ventricular fibrillation
D) Third-degree heart block
Correct Answer: B) Normal sinus rhythm
Rationale: Normal sinus rhythm has a regular rate, a P wave before each
QRS, and consistent AV conduction.
Q8. Which rhythm is characterized by an irregularly irregular ventricular
response and absence of consistent P waves?
A) Sinus bradycardia
B) Atrial fibrillation
C) Sinus tachycardia
D) Ventricular tachycardia
Correct Answer: B) Atrial fibrillation
Rationale: Atrial fibrillation produces chaotic atrial activity and an
irregularly irregular ventricular response.
Q9. Why is atrial fibrillation clinically significant?
A) It increases the risk of thrombus formation and stroke.
B) It always causes complete heart block.
C) It eliminates ventricular contraction.
D) It always produces cardiac arrest.
Correct Answer: A) It increases the risk of thrombus formation and stroke.
Rationale: Ineffective atrial contraction promotes blood stasis and thrombus
formation, which can embolize and cause stroke.
2026/2027 Herzing University
Q1. Which component of an ECG represents ventricular depolarization?
A) P wave
B) PR interval
C) QRS complex
D) T wave
Correct Answer: C) QRS complex
Rationale: The QRS complex represents ventricular depolarization, which
initiates ventricular contraction.
Q2. Which ECG component represents atrial depolarization?
A) P wave
B) QRS complex
C) ST segment
D) T wave
Correct Answer: A) P wave
Rationale: The P wave represents electrical activation of the atria.
Q3. Which interval reflects the time from the beginning of atrial
depolarization through conduction to the ventricles?
A) QT interval
B) PR interval
C) ST segment
D) QRS interval
Correct Answer: B) PR interval
Rationale: The PR interval represents conduction from the atria through the
AV node and His-Purkinje system to the ventricles.
Q4. What is the expected normal PR interval?
A) 0.02–0.04 seconds
B) 0.06–0.10 seconds
C) 0.12–0.20 seconds
D) 0.24–0.30 seconds
Correct Answer: C) 0.12–0.20 seconds
Rationale: A normal PR interval is generally 0.12 to 0.20 seconds.
Q5. What does the QT interval represent?
A) Atrial depolarization only
B) Ventricular depolarization and repolarization
C) AV-node conduction only
, D) Atrial repolarization only
Correct Answer: B) Ventricular depolarization and repolarization
Rationale: The QT interval encompasses ventricular electrical activation
and recovery.
Q6. Which action should the nurse take when preparing a client for ECG
monitoring?
A) Place electrodes over clean, dry skin.
B) Place electrodes over clothing.
C) Apply electrodes over excessive lotion.
D) Place electrodes over thick hair without preparation.
Correct Answer: A) Place electrodes over clean, dry skin.
Rationale: Clean, dry skin improves electrode contact and reduces artifact.
Q7. A client has a regular rhythm with a rate of 78/min, a P wave before
every QRS complex, and a constant PR interval. Which rhythm is present?
A) Atrial fibrillation
B) Normal sinus rhythm
C) Ventricular fibrillation
D) Third-degree heart block
Correct Answer: B) Normal sinus rhythm
Rationale: Normal sinus rhythm has a regular rate, a P wave before each
QRS, and consistent AV conduction.
Q8. Which rhythm is characterized by an irregularly irregular ventricular
response and absence of consistent P waves?
A) Sinus bradycardia
B) Atrial fibrillation
C) Sinus tachycardia
D) Ventricular tachycardia
Correct Answer: B) Atrial fibrillation
Rationale: Atrial fibrillation produces chaotic atrial activity and an
irregularly irregular ventricular response.
Q9. Why is atrial fibrillation clinically significant?
A) It increases the risk of thrombus formation and stroke.
B) It always causes complete heart block.
C) It eliminates ventricular contraction.
D) It always produces cardiac arrest.
Correct Answer: A) It increases the risk of thrombus formation and stroke.
Rationale: Ineffective atrial contraction promotes blood stasis and thrombus
formation, which can embolize and cause stroke.
