NUR 205 | NUR 205 Med Surg Exam 2 Version 2 |
Questions with Correct Answers and Expert
Explanation for Each Question | Saint Paul’s School
of Nursing
1. What is the normal duration for a PR interval on an ECG strip?
A. 0.04 to 0.10 seconds
B. 0.06 to 0.12 seconds
C. 0.20 to 0.40 seconds
D. 0.12 to 0.20 seconds
Correct Answer: D
Expert Explanation: The PR interval represents the time required for atrial
depolarization and the delay at the AV node. A normal measurement is between
0.12 and 0.20 seconds, which corresponds to three to five small boxes. Intervals
longer than 0.20 seconds indicate a conduction delay, commonly seen in first-degree
heart block. Shortened intervals may suggest that the impulse originated
somewhere other than the SA node. Accurate measurement is a fundamental skill
for interpreting cardiac rhythms effectively.
2. A patient is found in ventricular fibrillation (VF). What is the nurse’s immediate
priority action?
A. Initiate immediate defibrillation
,B. Perform a synchronized cardioversion
C. Administer a bolus of Amiodarone
D. Check for a carotid pulse for 10 seconds
Correct Answer: A
Expert Explanation: Ventricular fibrillation is a pulseless, life-threatening rhythm
that requires rapid electrical therapy to restore a heartbeat. Defibrillation is the
most effective treatment for VF and pulseless ventricular tachycardia. While CPR is
necessary while waiting for the device, it cannot convert the rhythm on its own.
Delaying shocks significantly decreases the patient’s chance of survival and
successful resuscitation. Following the shock, the nurse should immediately resume
chest compressions for two minutes.
3. Which ABG result is most indicative of acute hypoxemic respiratory failure?
A. PaO2 of 85 mmHg on room air
B. PaCO2 of 55 mmHg with pH of 7.25
C. HCO3 of 30 mEq/L with pH of 7.48
D. PaO2 of 50 mmHg on 60% oxygen
Correct Answer: D
,Expert Explanation: Acute hypoxemic respiratory failure is defined by a low
arterial oxygen tension despite supplemental oxygen. A PaO2 of 60 mmHg or less
when receiving an FiO2 of 60% or more confirms this diagnosis. The other options
represent respiratory acidosis or compensated metabolic alkalosis, which differ
from primary hypoxemia. This condition often results from V/Q mismatching or
intrapulmonary shunting. Close monitoring and escalation of respiratory support
are required to prevent tissue hypoxia.
4. A patient with symptomatic bradycardia (HR 38) is unresponsive to initial nursing
interventions. Which medication should the nurse prepare?
A. Lidocaine
B. Atropine
C. Digoxin
D. Amiodarone
Correct Answer: B
Expert Explanation: Atropine is the first-line medication used to increase heart
rate in patients with symptomatic bradycardia. It works by blocking
parasympathetic influences on the SA and AV nodes. The standard dose is 1 mg IV
every 3 to 5 minutes up to a total of 3 mg. If atropine is ineffective, the nurse may
, prepare for transcutaneous pacing or dopamine infusions. Monitoring for improved
hemodynamics and increased heart rate is essential after administration.
5. A nurse notes new-onset crackles in the bases of the lungs and an S3 gallop in a
patient post-myocardial infarction. What does this likely indicate?
A. Pulmonary embolism
B. Ventricular septal rupture
C. Acute pericarditis
D. Left-sided heart failure
Correct Answer: D
Expert Explanation: The presence of an S3 heart sound and pulmonary crackles
are classic signs of heart failure following an MI. These symptoms indicate that the
left ventricle is failing to pump blood forward effectively, causing backflow into the
lungs. This complication occurs because damaged myocardium cannot sustain
adequate cardiac output. Early detection is vital to prevent the progression into
cardiogenic shock or acute pulmonary edema. Diuretics and afterload reducers are
typically prescribed to manage these symptoms.
6. A patient in atrial fibrillation (AFib) is scheduled for an elective cardioversion.
Which medication is most important to confirm the patient has been taking?
A. Beta-blocker
Questions with Correct Answers and Expert
Explanation for Each Question | Saint Paul’s School
of Nursing
1. What is the normal duration for a PR interval on an ECG strip?
A. 0.04 to 0.10 seconds
B. 0.06 to 0.12 seconds
C. 0.20 to 0.40 seconds
D. 0.12 to 0.20 seconds
Correct Answer: D
Expert Explanation: The PR interval represents the time required for atrial
depolarization and the delay at the AV node. A normal measurement is between
0.12 and 0.20 seconds, which corresponds to three to five small boxes. Intervals
longer than 0.20 seconds indicate a conduction delay, commonly seen in first-degree
heart block. Shortened intervals may suggest that the impulse originated
somewhere other than the SA node. Accurate measurement is a fundamental skill
for interpreting cardiac rhythms effectively.
2. A patient is found in ventricular fibrillation (VF). What is the nurse’s immediate
priority action?
A. Initiate immediate defibrillation
,B. Perform a synchronized cardioversion
C. Administer a bolus of Amiodarone
D. Check for a carotid pulse for 10 seconds
Correct Answer: A
Expert Explanation: Ventricular fibrillation is a pulseless, life-threatening rhythm
that requires rapid electrical therapy to restore a heartbeat. Defibrillation is the
most effective treatment for VF and pulseless ventricular tachycardia. While CPR is
necessary while waiting for the device, it cannot convert the rhythm on its own.
Delaying shocks significantly decreases the patient’s chance of survival and
successful resuscitation. Following the shock, the nurse should immediately resume
chest compressions for two minutes.
3. Which ABG result is most indicative of acute hypoxemic respiratory failure?
A. PaO2 of 85 mmHg on room air
B. PaCO2 of 55 mmHg with pH of 7.25
C. HCO3 of 30 mEq/L with pH of 7.48
D. PaO2 of 50 mmHg on 60% oxygen
Correct Answer: D
,Expert Explanation: Acute hypoxemic respiratory failure is defined by a low
arterial oxygen tension despite supplemental oxygen. A PaO2 of 60 mmHg or less
when receiving an FiO2 of 60% or more confirms this diagnosis. The other options
represent respiratory acidosis or compensated metabolic alkalosis, which differ
from primary hypoxemia. This condition often results from V/Q mismatching or
intrapulmonary shunting. Close monitoring and escalation of respiratory support
are required to prevent tissue hypoxia.
4. A patient with symptomatic bradycardia (HR 38) is unresponsive to initial nursing
interventions. Which medication should the nurse prepare?
A. Lidocaine
B. Atropine
C. Digoxin
D. Amiodarone
Correct Answer: B
Expert Explanation: Atropine is the first-line medication used to increase heart
rate in patients with symptomatic bradycardia. It works by blocking
parasympathetic influences on the SA and AV nodes. The standard dose is 1 mg IV
every 3 to 5 minutes up to a total of 3 mg. If atropine is ineffective, the nurse may
, prepare for transcutaneous pacing or dopamine infusions. Monitoring for improved
hemodynamics and increased heart rate is essential after administration.
5. A nurse notes new-onset crackles in the bases of the lungs and an S3 gallop in a
patient post-myocardial infarction. What does this likely indicate?
A. Pulmonary embolism
B. Ventricular septal rupture
C. Acute pericarditis
D. Left-sided heart failure
Correct Answer: D
Expert Explanation: The presence of an S3 heart sound and pulmonary crackles
are classic signs of heart failure following an MI. These symptoms indicate that the
left ventricle is failing to pump blood forward effectively, causing backflow into the
lungs. This complication occurs because damaged myocardium cannot sustain
adequate cardiac output. Early detection is vital to prevent the progression into
cardiogenic shock or acute pulmonary edema. Diuretics and afterload reducers are
typically prescribed to manage these symptoms.
6. A patient in atrial fibrillation (AFib) is scheduled for an elective cardioversion.
Which medication is most important to confirm the patient has been taking?
A. Beta-blocker
