EMERGENCY NURSE PRACTITIONER (ENP)
EXAMINATIONbank - 149 Questions and Answers with
Detailed Rationales
About This Exam Bank
This comprehensive 149-question exam bank is designed to prepare candidates for EMERGENCY NURSE
PRACTITIONER (ENP) EXAMINATIONbank. Every question is aligned with the latest official content outline and
includes a detailed, evidence-based rationale, an explanation of why each remaining option is incorrect, and a
supporting reference.
Keywords
EMERGENCY NURSE PRACTITIONER (ENP) EXAMINATIONbank, exam bank, practice questions, verified
answers, detailed rationales, test prep, study guide, review questions, certification exam, latest update,
EMERGENCY NURSE PRACTITIONER (ENP) EXAMINATIONbank, exam bank, practice questions, verified
answers, detailed rationales, EMERGENCY NURSE PRACTITIONER (ENP) EXAMINATIONbank, exam bank,
practice questions, verified answers, detailed rationales, test prep, study guide, review questions
PART 1: SYNTHESIZE HISTORY, PHYSICAL EXAMINATION, AND DIAGNOSTIC DATA TO
FORMULATE PRIORITIZED DIFFERENTIAL DIAGNOSES IN UNDIFFERENTIATED
EMERGENCY PRESENTATIONS
1. A patient with acute decompensated heart failure is receiving high-dose IV furosemide. Which arterial blood gas
pattern most specifically indicates that diuresis has produced a contraction alkalosis rather than a respiratory
compensation?
A) pH 7.52, PaCO2 30, HCO3 24
B) pH 7.48, PaCO2 48, HCO3 34
C) pH 7.50, PaCO2 42, HCO3 32
D) pH 7.30, PaCO2 50, HCO3 25
' Correct Answer: C
Rationale: Contraction alkalosis from aggressive loop diuresis raises serum HCO3 with minimal primary
respiratory drive, yielding elevated pH and HCO3 with a near-normal PaCO2. Option A reflects respiratory alkalosis
(low PaCO2), B reflects metabolic alkalosis with compensatory hypoventilation, and D reflects respiratory acidosis.
2. A patient presents with sudden-onset severe headache and is being evaluated for subarachnoid hemorrhage.
Non-contrast head CT is negative but symptom onset was 8 hours ago. Which next step is most consistent with
current evidence-based guidelines?
A) Discharge with outpatient MRI in 1 week
B) Lumbar puncture immediately for xanthochromia
C) CT angiography of the brain
D) Empiric nimodipine and admission without further testing
' Correct Answer: B
Rationale: Within 6–12 hours, CT sensitivity remains high but not absolute; when CT is negative and suspicion
persists, lumbar puncture for xanthochromia is the guideline-endorsed next step. CTA evaluates vascular
malformations but does not exclude SAH, and empiric treatment without diagnosis is inappropriate.
Page 1
,3. A patient with a suspected scaphoid fracture has negative initial plain radiographs but persistent snuffbox
tenderness. Which management strategy best reflects current evidence to prevent nonunion?
A) Discharge with analgesia and repeat X-ray in 2 weeks
B) Apply a thumb spica splint and obtain MRI or CT within 1 week
C) Perform immediate open reduction internal fixation
D) Obtain a bone scan and cast if positive
' Correct Answer: B
Rationale: Occult scaphoid fractures carry high nonunion risk; immobilization with thumb spica and advanced
imaging (MRI preferred) within a week is standard. Plain radiograph follow-up alone delays diagnosis, immediate
surgery is not indicated without confirmed fracture, and bone scan is less specific than MRI.
4. A patient with severe metabolic acidosis from diabetic ketoacidosis has a serum potassium of 3.1 mEq/L. Which
action is most appropriate before initiating an insulin infusion?
A) Begin insulin immediately and recheck potassium in 2 hours
B) Administer IV potassium chloride until potassium >3.3 mEq/L
C) Give sodium bicarbonate to correct acidosis first
D) Hold insulin and administer calcium gluconate
' Correct Answer: B
Rationale: Insulin drives potassium intracellularly and can precipitate life-threatening hypokalemia; guidelines
mandate repletion to >3.3 mEq/L before insulin. Immediate insulin risks arrhythmia, bicarbonate is not first-line for
pH >6.9, and calcium is for hyperkalemia with ECG changes.
5. A patient presents with acute onset of unilateral vision loss and a suspected central retinal artery occlusion. Which
finding on fundoscopic examination is most characteristic?
A) Cherry-red spot at the macula
B) Flame-shaped hemorrhages
C) Disc edema with venous engorgement
D) Retinal detachment with a tear
' Correct Answer: A
Rationale: CRAO produces a pale retina with a cherry-red spot at the fovea due to choroidal perfusion. Flame
hemorrhages suggest hypertensive retinopathy, disc edema with venous engorgement suggests central retinal vein
occlusion, and retinal detachment presents with flashes and a visible tear.
6. A patient with a known seizure disorder presents with status epilepticus. After two adequate doses of a
benzodiazepine, which next agent is most appropriate for emergent control per current guidelines?
A) Phenytoin 20 mg/kg IV at 50 mg/min
B) Levetiracetam 60 mg/kg IV over 10 minutes
C) Propofol bolus 2 mg/kg followed by infusion
D) Oral valproic acid loading
' Correct Answer: B
Rationale: Current guidelines recommend IV levetiracetam, fosphenytoin, or valproate after benzodiazepines;
levetiracetam has a favorable safety profile and rapid administration. Phenytoin infusion is slower and riskier,
propofol is for refractory status, and oral loading is inappropriate in an emergency.
7. A patient with a suspected acute aortic dissection is being evaluated. Which imaging modality is the most
appropriate initial study in a hemodynamically stable patient with a history of contrast allergy?
A) CT angiography of the chest
B) Transthoracic echocardiography
Page 2
, C) MRI of the chest
D) Transesophageal echocardiography
' Correct Answer: C
Rationale: MRI avoids iodinated contrast and is highly sensitive for aortic dissection in stable patients with
contrast allergy. CT angiography requires contrast, TTE has limited sensitivity for the entire aorta, and TEE is
invasive and typically reserved for unstable patients or when MRI is unavailable.
8. A patient with a suspected tension pneumothorax is being managed in the emergency department. Which
intervention is the most immediate life-saving step?
A) Needle decompression in the second intercostal space at the midclavicular line
B) Chest tube insertion at the fifth intercostal space
C) Administration of high-flow oxygen and observation
D) Portable chest radiograph to confirm diagnosis
' Correct Answer: A
Rationale: Tension pneumothorax is a clinical diagnosis requiring immediate needle decompression; waiting for
imaging or chest tube placement can be fatal. Oxygen alone is insufficient, and chest tube is definitive but not the
first immediate step.
9. A patient with a suspected acute ischemic stroke has a blood glucose of 45 mg/dL. Which action should be taken
before considering thrombolytic therapy?
A) Proceed with thrombolysis immediately
B) Administer IV dextrose and reassess neurological deficits
C) Give insulin to normalize glucose
D) Obtain MRI to confirm stroke
' Correct Answer: B
Rationale: Hypoglycemia can mimic stroke and must be corrected before thrombolysis; if deficits resolve,
thrombolytics are contraindicated. Immediate thrombolysis risks unnecessary hemorrhage, insulin would worsen
hypoglycemia, and MRI delays time-sensitive treatment.
10. A patient with septic shock remains hypotensive despite 30 mL/kg of crystalloid and is initiated on
norepinephrine. Which parameter best reflects adequate tissue perfusion when interpreting a narrowed central
venous-to-arterial CO gap (Pcv-aCO < 6 mmHg)?
A) It indicates anaerobic metabolism has resolved regardless of lactate trend
B) It suggests adequate cardiac output is matching cellular demand, though lactate may lag
C) It confirms the patient no longer requires vasopressor support
D) It correlates directly with a supranormal mixed venous oxygen saturation
' Correct Answer: B
Rationale: A Pcv-aCO ‚ < 6 mmHg suggests flow is adequate to meet cellular demand, even if lactate clearance
lags due to washout or hepatic dysfunction. It does not independently confirm resolution of anaerobic metabolism or
wean readiness from vasopressors, nor does it guarantee supranormal SvO.
11. During rapid sequence intubation of a trauma patient with a suspected difficult airway, which preoxygenation
strategy most reliably extends the safe apnea time while minimizing gastric insufflation risk?
A) High-flow nasal cannula at 15 L/min alone for 3 minutes
B) Non-rebreather mask at 15 L/min for 5 minutes
C) Apneic oxygenation via nasal cannula plus preoxygenation with a non-rebreather and PEEP valve
D) Bag-valve-mask ventilation with cricoid pressure throughout induction
' Correct Answer: C
Page 3
, Rationale: Combining preoxygenation with a non-rebreather/PEEP valve and continued apneic nasal oxygen
maximizes alveolar reserve and delays desaturation. Bag-valve-mask with cricoid pressure risks gastric insufflation
and aspiration, and HFNC or NRB alone provide less alveolar recruitment.
12. A patient presents with sudden-onset tearing chest pain radiating to the back, a 20 mmHg interarm blood
pressure differential, and a widened mediastinum on chest radiograph. Which finding on bedside ultrasound most
directly supports the diagnosis of ascending aortic dissection?
A) Pericardial effusion with right ventricular collapse
B) Intimal flap visualized in the aortic root on parasternal long-axis view
C) Dilated inferior vena cava with <50% collapse
D) Reduced left ventricular ejection fraction with global hypokinesis
' Correct Answer: B
Rationale: Direct visualization of an intimal flap in the aortic root is the most specific sonographic sign of
ascending aortic dissection. Pericardial effusion may indicate rupture but is nonspecific; IVC and LV findings reflect
hemodynamics rather than the dissection itself.
13. A patient with acute ischemic stroke has a National Institutes of Health Stroke Scale (NIHSS) score of 14 and
presents 4.5 hours after symptom onset. Non-contrast CT shows no hemorrhage but a hyperdense MCA sign. Which
management decision is most appropriate per current guidelines?
A) Administer IV alteplase 0.9 mg/kg after excluding contraindications
B) Proceed directly to mechanical thrombectomy without thrombolysis
C) Administer aspirin 325 mg immediately and admit for monitoring
D) Obtain CT angiography and defer all reperfusion therapy pending results
' Correct Answer: A
Rationale: IV alteplase is indicated within 4.5 hours for eligible patients with disabling deficits and no hemorrhage,
even with a hyperdense MCA sign. Mechanical thrombectomy may follow if a large vessel occlusion is confirmed,
but thrombolysis should not be withheld; aspirin is contraindicated acutely.
14. Which pathophysiologic mechanism best explains the development of neurogenic pulmonary edema following a
severe traumatic brain injury?
A) Direct alveolar injury from aspiration of gastric contents
B) Massive sympathetic surge causing pulmonary vasoconstriction and increased capillary permeability
C) Left ventricular failure due to preexisting coronary artery disease
D) Fluid overload from aggressive isotonic resuscitation
' Correct Answer: B
Rationale: Neurogenic pulmonary edema results from a catecholamine surge after CNS injury, causing pulmonary
vasoconstriction, increased capillary permeability, and hydrostatic edema. Aspiration, cardiac failure, and fluid
overload are alternative or contributing mechanisms but not the primary neurogenic pathway.
15. A patient on chronic high-dose corticosteroids presents with hypotension and hypoglycemia unresponsive to
fluid resuscitation and dextrose. Which additional intervention is most critical to initiate while awaiting confirmatory
testing?
A) Norepinephrine infusion to maintain mean arterial pressure
B) Intravenous hydrocortisone 100 mg immediately
C) Broad-spectrum antibiotics after blood cultures
D) Fludrocortisone 0.1 mg orally
' Correct Answer: B
Page 4
EXAMINATIONbank - 149 Questions and Answers with
Detailed Rationales
About This Exam Bank
This comprehensive 149-question exam bank is designed to prepare candidates for EMERGENCY NURSE
PRACTITIONER (ENP) EXAMINATIONbank. Every question is aligned with the latest official content outline and
includes a detailed, evidence-based rationale, an explanation of why each remaining option is incorrect, and a
supporting reference.
Keywords
EMERGENCY NURSE PRACTITIONER (ENP) EXAMINATIONbank, exam bank, practice questions, verified
answers, detailed rationales, test prep, study guide, review questions, certification exam, latest update,
EMERGENCY NURSE PRACTITIONER (ENP) EXAMINATIONbank, exam bank, practice questions, verified
answers, detailed rationales, EMERGENCY NURSE PRACTITIONER (ENP) EXAMINATIONbank, exam bank,
practice questions, verified answers, detailed rationales, test prep, study guide, review questions
PART 1: SYNTHESIZE HISTORY, PHYSICAL EXAMINATION, AND DIAGNOSTIC DATA TO
FORMULATE PRIORITIZED DIFFERENTIAL DIAGNOSES IN UNDIFFERENTIATED
EMERGENCY PRESENTATIONS
1. A patient with acute decompensated heart failure is receiving high-dose IV furosemide. Which arterial blood gas
pattern most specifically indicates that diuresis has produced a contraction alkalosis rather than a respiratory
compensation?
A) pH 7.52, PaCO2 30, HCO3 24
B) pH 7.48, PaCO2 48, HCO3 34
C) pH 7.50, PaCO2 42, HCO3 32
D) pH 7.30, PaCO2 50, HCO3 25
' Correct Answer: C
Rationale: Contraction alkalosis from aggressive loop diuresis raises serum HCO3 with minimal primary
respiratory drive, yielding elevated pH and HCO3 with a near-normal PaCO2. Option A reflects respiratory alkalosis
(low PaCO2), B reflects metabolic alkalosis with compensatory hypoventilation, and D reflects respiratory acidosis.
2. A patient presents with sudden-onset severe headache and is being evaluated for subarachnoid hemorrhage.
Non-contrast head CT is negative but symptom onset was 8 hours ago. Which next step is most consistent with
current evidence-based guidelines?
A) Discharge with outpatient MRI in 1 week
B) Lumbar puncture immediately for xanthochromia
C) CT angiography of the brain
D) Empiric nimodipine and admission without further testing
' Correct Answer: B
Rationale: Within 6–12 hours, CT sensitivity remains high but not absolute; when CT is negative and suspicion
persists, lumbar puncture for xanthochromia is the guideline-endorsed next step. CTA evaluates vascular
malformations but does not exclude SAH, and empiric treatment without diagnosis is inappropriate.
Page 1
,3. A patient with a suspected scaphoid fracture has negative initial plain radiographs but persistent snuffbox
tenderness. Which management strategy best reflects current evidence to prevent nonunion?
A) Discharge with analgesia and repeat X-ray in 2 weeks
B) Apply a thumb spica splint and obtain MRI or CT within 1 week
C) Perform immediate open reduction internal fixation
D) Obtain a bone scan and cast if positive
' Correct Answer: B
Rationale: Occult scaphoid fractures carry high nonunion risk; immobilization with thumb spica and advanced
imaging (MRI preferred) within a week is standard. Plain radiograph follow-up alone delays diagnosis, immediate
surgery is not indicated without confirmed fracture, and bone scan is less specific than MRI.
4. A patient with severe metabolic acidosis from diabetic ketoacidosis has a serum potassium of 3.1 mEq/L. Which
action is most appropriate before initiating an insulin infusion?
A) Begin insulin immediately and recheck potassium in 2 hours
B) Administer IV potassium chloride until potassium >3.3 mEq/L
C) Give sodium bicarbonate to correct acidosis first
D) Hold insulin and administer calcium gluconate
' Correct Answer: B
Rationale: Insulin drives potassium intracellularly and can precipitate life-threatening hypokalemia; guidelines
mandate repletion to >3.3 mEq/L before insulin. Immediate insulin risks arrhythmia, bicarbonate is not first-line for
pH >6.9, and calcium is for hyperkalemia with ECG changes.
5. A patient presents with acute onset of unilateral vision loss and a suspected central retinal artery occlusion. Which
finding on fundoscopic examination is most characteristic?
A) Cherry-red spot at the macula
B) Flame-shaped hemorrhages
C) Disc edema with venous engorgement
D) Retinal detachment with a tear
' Correct Answer: A
Rationale: CRAO produces a pale retina with a cherry-red spot at the fovea due to choroidal perfusion. Flame
hemorrhages suggest hypertensive retinopathy, disc edema with venous engorgement suggests central retinal vein
occlusion, and retinal detachment presents with flashes and a visible tear.
6. A patient with a known seizure disorder presents with status epilepticus. After two adequate doses of a
benzodiazepine, which next agent is most appropriate for emergent control per current guidelines?
A) Phenytoin 20 mg/kg IV at 50 mg/min
B) Levetiracetam 60 mg/kg IV over 10 minutes
C) Propofol bolus 2 mg/kg followed by infusion
D) Oral valproic acid loading
' Correct Answer: B
Rationale: Current guidelines recommend IV levetiracetam, fosphenytoin, or valproate after benzodiazepines;
levetiracetam has a favorable safety profile and rapid administration. Phenytoin infusion is slower and riskier,
propofol is for refractory status, and oral loading is inappropriate in an emergency.
7. A patient with a suspected acute aortic dissection is being evaluated. Which imaging modality is the most
appropriate initial study in a hemodynamically stable patient with a history of contrast allergy?
A) CT angiography of the chest
B) Transthoracic echocardiography
Page 2
, C) MRI of the chest
D) Transesophageal echocardiography
' Correct Answer: C
Rationale: MRI avoids iodinated contrast and is highly sensitive for aortic dissection in stable patients with
contrast allergy. CT angiography requires contrast, TTE has limited sensitivity for the entire aorta, and TEE is
invasive and typically reserved for unstable patients or when MRI is unavailable.
8. A patient with a suspected tension pneumothorax is being managed in the emergency department. Which
intervention is the most immediate life-saving step?
A) Needle decompression in the second intercostal space at the midclavicular line
B) Chest tube insertion at the fifth intercostal space
C) Administration of high-flow oxygen and observation
D) Portable chest radiograph to confirm diagnosis
' Correct Answer: A
Rationale: Tension pneumothorax is a clinical diagnosis requiring immediate needle decompression; waiting for
imaging or chest tube placement can be fatal. Oxygen alone is insufficient, and chest tube is definitive but not the
first immediate step.
9. A patient with a suspected acute ischemic stroke has a blood glucose of 45 mg/dL. Which action should be taken
before considering thrombolytic therapy?
A) Proceed with thrombolysis immediately
B) Administer IV dextrose and reassess neurological deficits
C) Give insulin to normalize glucose
D) Obtain MRI to confirm stroke
' Correct Answer: B
Rationale: Hypoglycemia can mimic stroke and must be corrected before thrombolysis; if deficits resolve,
thrombolytics are contraindicated. Immediate thrombolysis risks unnecessary hemorrhage, insulin would worsen
hypoglycemia, and MRI delays time-sensitive treatment.
10. A patient with septic shock remains hypotensive despite 30 mL/kg of crystalloid and is initiated on
norepinephrine. Which parameter best reflects adequate tissue perfusion when interpreting a narrowed central
venous-to-arterial CO gap (Pcv-aCO < 6 mmHg)?
A) It indicates anaerobic metabolism has resolved regardless of lactate trend
B) It suggests adequate cardiac output is matching cellular demand, though lactate may lag
C) It confirms the patient no longer requires vasopressor support
D) It correlates directly with a supranormal mixed venous oxygen saturation
' Correct Answer: B
Rationale: A Pcv-aCO ‚ < 6 mmHg suggests flow is adequate to meet cellular demand, even if lactate clearance
lags due to washout or hepatic dysfunction. It does not independently confirm resolution of anaerobic metabolism or
wean readiness from vasopressors, nor does it guarantee supranormal SvO.
11. During rapid sequence intubation of a trauma patient with a suspected difficult airway, which preoxygenation
strategy most reliably extends the safe apnea time while minimizing gastric insufflation risk?
A) High-flow nasal cannula at 15 L/min alone for 3 minutes
B) Non-rebreather mask at 15 L/min for 5 minutes
C) Apneic oxygenation via nasal cannula plus preoxygenation with a non-rebreather and PEEP valve
D) Bag-valve-mask ventilation with cricoid pressure throughout induction
' Correct Answer: C
Page 3
, Rationale: Combining preoxygenation with a non-rebreather/PEEP valve and continued apneic nasal oxygen
maximizes alveolar reserve and delays desaturation. Bag-valve-mask with cricoid pressure risks gastric insufflation
and aspiration, and HFNC or NRB alone provide less alveolar recruitment.
12. A patient presents with sudden-onset tearing chest pain radiating to the back, a 20 mmHg interarm blood
pressure differential, and a widened mediastinum on chest radiograph. Which finding on bedside ultrasound most
directly supports the diagnosis of ascending aortic dissection?
A) Pericardial effusion with right ventricular collapse
B) Intimal flap visualized in the aortic root on parasternal long-axis view
C) Dilated inferior vena cava with <50% collapse
D) Reduced left ventricular ejection fraction with global hypokinesis
' Correct Answer: B
Rationale: Direct visualization of an intimal flap in the aortic root is the most specific sonographic sign of
ascending aortic dissection. Pericardial effusion may indicate rupture but is nonspecific; IVC and LV findings reflect
hemodynamics rather than the dissection itself.
13. A patient with acute ischemic stroke has a National Institutes of Health Stroke Scale (NIHSS) score of 14 and
presents 4.5 hours after symptom onset. Non-contrast CT shows no hemorrhage but a hyperdense MCA sign. Which
management decision is most appropriate per current guidelines?
A) Administer IV alteplase 0.9 mg/kg after excluding contraindications
B) Proceed directly to mechanical thrombectomy without thrombolysis
C) Administer aspirin 325 mg immediately and admit for monitoring
D) Obtain CT angiography and defer all reperfusion therapy pending results
' Correct Answer: A
Rationale: IV alteplase is indicated within 4.5 hours for eligible patients with disabling deficits and no hemorrhage,
even with a hyperdense MCA sign. Mechanical thrombectomy may follow if a large vessel occlusion is confirmed,
but thrombolysis should not be withheld; aspirin is contraindicated acutely.
14. Which pathophysiologic mechanism best explains the development of neurogenic pulmonary edema following a
severe traumatic brain injury?
A) Direct alveolar injury from aspiration of gastric contents
B) Massive sympathetic surge causing pulmonary vasoconstriction and increased capillary permeability
C) Left ventricular failure due to preexisting coronary artery disease
D) Fluid overload from aggressive isotonic resuscitation
' Correct Answer: B
Rationale: Neurogenic pulmonary edema results from a catecholamine surge after CNS injury, causing pulmonary
vasoconstriction, increased capillary permeability, and hydrostatic edema. Aspiration, cardiac failure, and fluid
overload are alternative or contributing mechanisms but not the primary neurogenic pathway.
15. A patient on chronic high-dose corticosteroids presents with hypotension and hypoglycemia unresponsive to
fluid resuscitation and dextrose. Which additional intervention is most critical to initiate while awaiting confirmatory
testing?
A) Norepinephrine infusion to maintain mean arterial pressure
B) Intravenous hydrocortisone 100 mg immediately
C) Broad-spectrum antibiotics after blood cultures
D) Fludrocortisone 0.1 mg orally
' Correct Answer: B
Page 4
