CEN Certified Emergency Nurse Practice Exam Study Guide Updated 2026
| Verified Questions and Answers with Detailed Rationales | Emergency Nursing
Assessment and Triage, Trauma and Injury Management, Cardiac and Respiratory
Emergencies, Neurological Crises and Stroke Care, Shock and Sepsis Management,
Toxicology and Environmental Emergencies, Pediatric and Geriatric Emergencies,
Disaster Preparedness, ACLS PALS TNCC Concepts, Patient Safety and Rapid
Response Interventions | Complete Exam Prep Resource for CEN Certification
Success
Question 1: A 58-year-old male presents to the emergency department with
crushing substernal chest pain radiating to his left jaw, diaphoresis, and nausea.
His ECG shows ST-segment elevation in leads II, III, and aVF. Which intervention
should the CEN prioritize immediately?
A. Administer sublingual nitroglycerin
B. Obtain a portable chest X-ray
C. Activate the cardiac catheterization lab
D. Apply oxygen via nasal cannula at 2 L/min
CORRECT ANSWER: C. Activate the cardiac catheterization lab
RATIONALE:In ST-elevation myocardial infarction (STEMI), time to reperfusion is critical.
Current ACC/AHA guidelines mandate immediate activation of the cardiac
catheterization lab for primary percutaneous coronary intervention (PCI) within 90
minutes of first medical contact. While oxygen, nitroglycerin, and diagnostics have
roles, they do not supersede timely reperfusion therapy in confirmed STEMI.
Question 2: Which assessment finding in a patient with suspected pulmonary
embolism requires the most urgent intervention?
A. Pleuritic chest pain
B. Tachycardia at 110 bpm
C. Systolic blood pressure of 82 mmHg
D. Oxygen saturation of 92% on room air
CORRECT ANSWER: C. Systolic blood pressure of 82 mmHg
RATIONALE:Hypotension (systolic BP <90 mmHg) in pulmonary embolism indicates
massive PE with right ventricular strain and hemodynamic instability, representing a life-
threatening emergency requiring immediate thrombolysis or embolectomy. Other
findings are concerning but do not indicate imminent cardiovascular collapse.
Question 3: A patient with known heart failure presents with acute dyspnea,
bilateral crackles, and frothy pink sputum. Which medication should the CEN
anticipate administering first?
A. Furosemide IV
B. Nitroglycerin IV infusion
C. Morphine sulfate IV
D. Dopamine infusion
,CORRECT ANSWER: B. Nitroglycerin IV infusion
RATIONALE:In acute cardiogenic pulmonary edema, nitroglycerin is first-line for rapid
preload and afterload reduction, improving cardiac output and reducing pulmonary
congestion. While furosemide is important, nitroglycerin acts faster to relieve
symptoms. Morphine is no longer routinely recommended due to respiratory depression
risks, and dopamine is reserved for cardiogenic shock.
Question 4: Which ECG finding is most specific for acute pericarditis?
A. ST-segment elevation with reciprocal changes
B. Diffuse ST-segment elevation with PR-segment depression
C. New left bundle branch block
D. T-wave inversion in V1-V4
CORRECT ANSWER: B. Diffuse ST-segment elevation with PR-segment depression
RATIONALE:Acute pericarditis classically presents with diffuse, concave-upward ST
elevation in multiple leads without reciprocal changes, plus PR-segment depression.
Reciprocal ST changes suggest STEMI; new LBBB or anterior T-wave inversions indicate
myocardial ischemia, not pericarditis.
Question 5: A patient with atrial fibrillation and rapid ventricular response presents
with hypotension and altered mental status. What is the priority intervention?
A. Administer diltiazem IV
B. Perform synchronized cardioversion
C. Start heparin infusion
D. Obtain stat troponin level
CORRECT ANSWER: B. Perform synchronized cardioversion
RATIONALE:Unstable atrial fibrillation with hypotension or altered mental status
requires immediate synchronized cardioversion per ACLS guidelines. Rate control
medications like diltiazem are contraindicated in hemodynamically unstable patients,
as they may worsen perfusion. Anticoagulation is important but not emergent in this
scenario.
Question 6: Which finding distinguishes neurogenic shock from hypovolemic shock
in a trauma patient?
A. Tachycardia
B. Bradycardia with hypotension
C. Cool, clammy skin
D. Elevated lactate level
CORRECT ANSWER: B. Bradycardia with hypotension
RATIONALE:Neurogenic shock, resulting from spinal cord injury, causes loss of
sympathetic tone leading to hypotension with paradoxical bradycardia. Hypovolemic
,shock typically presents with tachycardia, cool/clammy skin, and elevated lactate due
to compensatory mechanisms. Bradycardia in shock is a red flag for neurogenic
etiology.
Question 7: A patient with suspected aortic dissection presents with tearing chest
pain radiating to the back. Which diagnostic test should the CEN prioritize?
A. Chest X-ray
B. CT angiography of the chest
C. Transthoracic echocardiogram
D. D-dimer assay
CORRECT ANSWER: B. CT angiography of the chest
RATIONALE:CT angiography is the gold standard for diagnosing aortic dissection due to
its high sensitivity and specificity for visualizing the intimal flap and extent of dissection.
While chest X-ray may show mediastinal widening, it lacks diagnostic certainty.
Echocardiogram is useful but operator-dependent; D-dimer is nonspecific and not
definitive.
Question 8: Which medication is contraindicated in a patient with suspected right
ventricular myocardial infarction?
A. Aspirin
B. Nitroglycerin
C. Heparin
D. Morphine
CORRECT ANSWER: B. Nitroglycerin
RATIONALE:Right ventricular infarction depends on preload for cardiac output.
Nitroglycerin reduces preload and can cause profound hypotension in these patients.
Aspirin, heparin, and cautious morphine use remain appropriate. Fluid resuscitation is
often first-line for RV infarction hypotension.
Question 9: A patient with hypertensive emergency (BP 220/130 mmHg) and acute
kidney injury requires IV antihypertensive therapy. Which agent is most
appropriate?
A. Hydralazine IV
B. Nicardipine IV infusion
C. Labetalol IV push
D. Nitroprusside IV infusion
CORRECT ANSWER: B. Nicardipine IV infusion
RATIONALE:Nicardipine is preferred in hypertensive emergencies with renal
involvement due to its predictable titration, minimal effect on renal blood flow, and
safety profile. Nitroprusside risks cyanide toxicity in renal impairment; hydralazine has
unpredictable effects; labetalol may worsen heart failure.
, Question 10: Which arrhythmia is most likely to deteriorate into ventricular
fibrillation without intervention?
A. Sinus tachycardia
B. Torsades de pointes
C. Atrial flutter with 2:1 block
D. Junctional rhythm
CORRECT ANSWER: B. Torsades de pointes
RATIONALE:Torsades de pointes is a polymorphic ventricular tachycardia associated
with prolonged QT interval that frequently degenerates into ventricular fibrillation.
Immediate magnesium sulfate administration and correction of underlying causes (e.g.,
electrolyte abnormalities) are critical. Other rhythms listed are less immediately life-
threatening.
Question 11: A patient with severe asthma exacerbation fails to improve after three
nebulized albuterol treatments and IV methylprednisolone. What is the next
appropriate intervention?
A. Administer ipratropium bromide nebulizer
B. Initiate IV magnesium sulfate
C. Prepare for non-invasive ventilation
D. Obtain arterial blood gas
CORRECT ANSWER: B. Initiate IV magnesium sulfate
RATIONALE:IV magnesium sulfate is recommended for severe asthma exacerbations
unresponsive to initial bronchodilators and steroids, as it promotes bronchodilation via
smooth muscle relaxation. Ipratropium is typically given with initial albuterol; NIV is
controversial in asthma due to air trapping risk; ABG may be obtained but does not treat
the exacerbation.
Question 12: Which finding indicates impending respiratory failure in a patient with
COPD exacerbation?
A. Use of accessory muscles
B. Paradoxical abdominal movement
C. Pursed-lip breathing
D. Oxygen saturation of 90%
CORRECT ANSWER: B. Paradoxical abdominal movement
RATIONALE:Paradoxical abdominal movement (abdomen moves inward during
inspiration) indicates diaphragmatic fatigue and impending respiratory muscle failure.
Accessory muscle use and pursed-lip breathing are compensatory mechanisms; SpO2
of 90% is concerning but not specific for imminent failure.
Question 13: A patient with suspected pulmonary embolism has a Wells' Score of
6.5. What is the most appropriate next diagnostic step?
| Verified Questions and Answers with Detailed Rationales | Emergency Nursing
Assessment and Triage, Trauma and Injury Management, Cardiac and Respiratory
Emergencies, Neurological Crises and Stroke Care, Shock and Sepsis Management,
Toxicology and Environmental Emergencies, Pediatric and Geriatric Emergencies,
Disaster Preparedness, ACLS PALS TNCC Concepts, Patient Safety and Rapid
Response Interventions | Complete Exam Prep Resource for CEN Certification
Success
Question 1: A 58-year-old male presents to the emergency department with
crushing substernal chest pain radiating to his left jaw, diaphoresis, and nausea.
His ECG shows ST-segment elevation in leads II, III, and aVF. Which intervention
should the CEN prioritize immediately?
A. Administer sublingual nitroglycerin
B. Obtain a portable chest X-ray
C. Activate the cardiac catheterization lab
D. Apply oxygen via nasal cannula at 2 L/min
CORRECT ANSWER: C. Activate the cardiac catheterization lab
RATIONALE:In ST-elevation myocardial infarction (STEMI), time to reperfusion is critical.
Current ACC/AHA guidelines mandate immediate activation of the cardiac
catheterization lab for primary percutaneous coronary intervention (PCI) within 90
minutes of first medical contact. While oxygen, nitroglycerin, and diagnostics have
roles, they do not supersede timely reperfusion therapy in confirmed STEMI.
Question 2: Which assessment finding in a patient with suspected pulmonary
embolism requires the most urgent intervention?
A. Pleuritic chest pain
B. Tachycardia at 110 bpm
C. Systolic blood pressure of 82 mmHg
D. Oxygen saturation of 92% on room air
CORRECT ANSWER: C. Systolic blood pressure of 82 mmHg
RATIONALE:Hypotension (systolic BP <90 mmHg) in pulmonary embolism indicates
massive PE with right ventricular strain and hemodynamic instability, representing a life-
threatening emergency requiring immediate thrombolysis or embolectomy. Other
findings are concerning but do not indicate imminent cardiovascular collapse.
Question 3: A patient with known heart failure presents with acute dyspnea,
bilateral crackles, and frothy pink sputum. Which medication should the CEN
anticipate administering first?
A. Furosemide IV
B. Nitroglycerin IV infusion
C. Morphine sulfate IV
D. Dopamine infusion
,CORRECT ANSWER: B. Nitroglycerin IV infusion
RATIONALE:In acute cardiogenic pulmonary edema, nitroglycerin is first-line for rapid
preload and afterload reduction, improving cardiac output and reducing pulmonary
congestion. While furosemide is important, nitroglycerin acts faster to relieve
symptoms. Morphine is no longer routinely recommended due to respiratory depression
risks, and dopamine is reserved for cardiogenic shock.
Question 4: Which ECG finding is most specific for acute pericarditis?
A. ST-segment elevation with reciprocal changes
B. Diffuse ST-segment elevation with PR-segment depression
C. New left bundle branch block
D. T-wave inversion in V1-V4
CORRECT ANSWER: B. Diffuse ST-segment elevation with PR-segment depression
RATIONALE:Acute pericarditis classically presents with diffuse, concave-upward ST
elevation in multiple leads without reciprocal changes, plus PR-segment depression.
Reciprocal ST changes suggest STEMI; new LBBB or anterior T-wave inversions indicate
myocardial ischemia, not pericarditis.
Question 5: A patient with atrial fibrillation and rapid ventricular response presents
with hypotension and altered mental status. What is the priority intervention?
A. Administer diltiazem IV
B. Perform synchronized cardioversion
C. Start heparin infusion
D. Obtain stat troponin level
CORRECT ANSWER: B. Perform synchronized cardioversion
RATIONALE:Unstable atrial fibrillation with hypotension or altered mental status
requires immediate synchronized cardioversion per ACLS guidelines. Rate control
medications like diltiazem are contraindicated in hemodynamically unstable patients,
as they may worsen perfusion. Anticoagulation is important but not emergent in this
scenario.
Question 6: Which finding distinguishes neurogenic shock from hypovolemic shock
in a trauma patient?
A. Tachycardia
B. Bradycardia with hypotension
C. Cool, clammy skin
D. Elevated lactate level
CORRECT ANSWER: B. Bradycardia with hypotension
RATIONALE:Neurogenic shock, resulting from spinal cord injury, causes loss of
sympathetic tone leading to hypotension with paradoxical bradycardia. Hypovolemic
,shock typically presents with tachycardia, cool/clammy skin, and elevated lactate due
to compensatory mechanisms. Bradycardia in shock is a red flag for neurogenic
etiology.
Question 7: A patient with suspected aortic dissection presents with tearing chest
pain radiating to the back. Which diagnostic test should the CEN prioritize?
A. Chest X-ray
B. CT angiography of the chest
C. Transthoracic echocardiogram
D. D-dimer assay
CORRECT ANSWER: B. CT angiography of the chest
RATIONALE:CT angiography is the gold standard for diagnosing aortic dissection due to
its high sensitivity and specificity for visualizing the intimal flap and extent of dissection.
While chest X-ray may show mediastinal widening, it lacks diagnostic certainty.
Echocardiogram is useful but operator-dependent; D-dimer is nonspecific and not
definitive.
Question 8: Which medication is contraindicated in a patient with suspected right
ventricular myocardial infarction?
A. Aspirin
B. Nitroglycerin
C. Heparin
D. Morphine
CORRECT ANSWER: B. Nitroglycerin
RATIONALE:Right ventricular infarction depends on preload for cardiac output.
Nitroglycerin reduces preload and can cause profound hypotension in these patients.
Aspirin, heparin, and cautious morphine use remain appropriate. Fluid resuscitation is
often first-line for RV infarction hypotension.
Question 9: A patient with hypertensive emergency (BP 220/130 mmHg) and acute
kidney injury requires IV antihypertensive therapy. Which agent is most
appropriate?
A. Hydralazine IV
B. Nicardipine IV infusion
C. Labetalol IV push
D. Nitroprusside IV infusion
CORRECT ANSWER: B. Nicardipine IV infusion
RATIONALE:Nicardipine is preferred in hypertensive emergencies with renal
involvement due to its predictable titration, minimal effect on renal blood flow, and
safety profile. Nitroprusside risks cyanide toxicity in renal impairment; hydralazine has
unpredictable effects; labetalol may worsen heart failure.
, Question 10: Which arrhythmia is most likely to deteriorate into ventricular
fibrillation without intervention?
A. Sinus tachycardia
B. Torsades de pointes
C. Atrial flutter with 2:1 block
D. Junctional rhythm
CORRECT ANSWER: B. Torsades de pointes
RATIONALE:Torsades de pointes is a polymorphic ventricular tachycardia associated
with prolonged QT interval that frequently degenerates into ventricular fibrillation.
Immediate magnesium sulfate administration and correction of underlying causes (e.g.,
electrolyte abnormalities) are critical. Other rhythms listed are less immediately life-
threatening.
Question 11: A patient with severe asthma exacerbation fails to improve after three
nebulized albuterol treatments and IV methylprednisolone. What is the next
appropriate intervention?
A. Administer ipratropium bromide nebulizer
B. Initiate IV magnesium sulfate
C. Prepare for non-invasive ventilation
D. Obtain arterial blood gas
CORRECT ANSWER: B. Initiate IV magnesium sulfate
RATIONALE:IV magnesium sulfate is recommended for severe asthma exacerbations
unresponsive to initial bronchodilators and steroids, as it promotes bronchodilation via
smooth muscle relaxation. Ipratropium is typically given with initial albuterol; NIV is
controversial in asthma due to air trapping risk; ABG may be obtained but does not treat
the exacerbation.
Question 12: Which finding indicates impending respiratory failure in a patient with
COPD exacerbation?
A. Use of accessory muscles
B. Paradoxical abdominal movement
C. Pursed-lip breathing
D. Oxygen saturation of 90%
CORRECT ANSWER: B. Paradoxical abdominal movement
RATIONALE:Paradoxical abdominal movement (abdomen moves inward during
inspiration) indicates diaphragmatic fatigue and impending respiratory muscle failure.
Accessory muscle use and pursed-lip breathing are compensatory mechanisms; SpO2
of 90% is concerning but not specific for imminent failure.
Question 13: A patient with suspected pulmonary embolism has a Wells' Score of
6.5. What is the most appropriate next diagnostic step?
