Midterm Examination
NR569 Differential Diagnosis in
Acute Care Practicum
2026/2027 Update | Weeks 1-4 Comprehensive Review | 90 Questions
Chamberlain College of Nursing
NR569: Differential Diagnosis in Acute Care Practicum
Verified Answers with Comprehensive Rationales
Cognitive Levels: 20% Recall | 45% Application | 35% Analysis
Question Types: 85% Scenario-Based (NGN-Enhanced) | 15% Direct Recall
,NR569 Midterm Exam | Differential Diagnosis in Acute Care Practicum 2026/2027 Update
Section 1: Foundations of Diagnostic Reasoning and Clinical Decision-Making
(Q1-Q12)
Q1: A 68-year-old male presents to the emergency department with acute onset chest pain. The ACNP begins
generating diagnostic hypotheses. Which approach best reflects the hypothesis-driven method of diagnostic reasoning
per 2026 guidelines?
A. Order a comprehensive metabolic panel and wait for results before forming any clinical impression
B. Generate multiple competing diagnoses simultaneously based on the initial presentation, then
systematically rule them in or out **[CORRECT]**
C. Rely solely on pattern recognition from previous similar patients to arrive at a single diagnosis immediately
D. Refer the patient to a specialist before initiating any diagnostic workup given the complexity
Correct Answer: B
Rationale: The hypothesis-driven method involves generating multiple diagnostic hypotheses early based on initial data, then
systematically testing each through focused assessment. This reduces cognitive bias and anchoring, which are leading causes of
diagnostic error in acute care per the 2026 National Academies of Medicine report. Option A delays clinical reasoning
inappropriately. Option C describes pattern recognition, prone to bias with atypical presentations. Option D defers reasoning
without initial assessment by the ACNP, which contradicts the scope of practice.
Q2: An ACNP evaluates a 55-year-old female with dyspnea. The Wells score estimates PE pre-test probability at
15%. A D-dimer returns at 450 ng/mL (negative below 500). Using Bayesian analysis, what is the most appropriate
next step?
A. Discharge the patient since the negative D-dimer conclusively rules out PE
B. Proceed directly to CTPA because the pre-test probability is too high for D-dimer
C. Calculate post-test probability using the negative likelihood ratio to determine if PE is excluded
**[CORRECT]**
D. Repeat the D-dimer in 24 hours to confirm the negative result before disposition
Correct Answer: C
Rationale: Bayesian analysis requires combining pre-test probability with test characteristics (likelihood ratios) to determine
post-test probability. The 2026 ACCP/ESC guidelines emphasize D-dimer interpretation must integrate clinical probability via
validated scoring. A D-dimer near the cutoff with moderate pre-test probability does not automatically exclude PE; the negative
likelihood ratio must be applied. If post-test probability remains above the test treatment threshold, further imaging is
warranted. Simply discharging or reflexively imaging both represent suboptimal diagnostic reasoning.
Q3: A 42-year-old female has 2 weeks of progressive fatigue, myalgias, and low-grade fevers. She was diagnosed with
viral syndrome 5 days ago but now presents with new petechiae on her lower extremities and gum bleeding. Which red
flag most significantly changes diagnostic urgency?
A. Duration of symptoms extending beyond 10 days without improvement
B. New onset bleeding manifestations suggesting a potential hematologic emergency **[CORRECT]**
C. Presence of myalgias which could indicate an autoimmune process
D. Low-grade fevers suggesting an undiagnosed infectious etiology requiring antibiotics
Correct Answer: B
Page 2
,NR569 Midterm Exam | Differential Diagnosis in Acute Care Practicum 2026/2027 Update
Rationale: New bleeding manifestations with progressive constitutional symptoms is a critical red flag dramatically shifting
diagnostic urgency. This suggests thrombocytopenia with bleeding risk, potentially indicating acute leukemia, aplastic anemia,
DIC, or severe sepsis. The 2026 NCCN and ASH guidelines emphasize new bleeding with systemic symptoms requires immediate
CBC with differential, coagulation studies, and peripheral smear. While duration, myalgias, and fevers are concerning, they
represent gradual progression rather than acute change signaling life-threatening pathology.
Q4: In the NGN Clinical Judgment Measurement Model (CJMM), which action best represents the "Analyze Cues"
step when a 75-year-old presents with confusion, hypotension (BP 88/50), and temperature 38.9 degrees Celsius?
A. Immediately administer broad-spectrum antibiotics and isotonic IV fluids
B. Recognize that the combination of altered mental status, hemodynamic instability, and fever form a cluster
suggesting sepsis **[CORRECT]**
C. Prioritize which diagnosis is most likely before obtaining additional clinical data
D. Evaluate the patient response to initial fluid resuscitation after 30 minutes
Correct Answer: B
Rationale: The Analyze Cues step in the CJMM involves recognizing patterns and relationships among clinical data to identify
clinical significance. In this scenario, the cluster of confusion (altered mental status), hypotension (hemodynamic instability),
and fever forms a recognizable pattern consistent with sepsis per Sepsis-3 criteria. Option A represents "Take Action," which
occurs after analysis and prioritization. Option C represents "Prioritize Hypotheses," which follows analysis. Option D represents
"Evaluate Outcomes," the final step. The 2026 NCSBN framework emphasizes that analyzing cues must precede generating
solutions or taking action.
Q5: An ACNP is caring for an 80-year-old female who presents with generalized weakness and falls over the past
week. Her vital signs are BP 130/80, HR 78, RR 16, T 37.0 degrees C, SpO2 97%. Her family reports she seems more
confused than usual. Which diagnostic testing strategy is most appropriate as the initial step?
A. Order a head CT immediately to evaluate for intracranial pathology given the confusion and falls
B. Obtain a comprehensive metabolic panel including calcium, TSH, and vitamin B12 level as the initial
diagnostic step **[CORRECT]**
C. Order a full cardiac workup including echocardiogram and Holter monitor given the nonspecific presentation in the
elderly
D. Discharge with physical therapy referral as this is a normal age-related decline in functional status
Correct Answer: B
Rationale: In elderly patients, altered mental status and generalized weakness have broad differential diagnoses, with metabolic
causes being among the most common and reversible. The 2026 American Geriatrics Society guidelines recommend initial
evaluation with comprehensive metabolic panel including electrolytes, glucose, renal function, calcium, TSH, and vitamin B12.
These tests can identify hyponatremia, hypercalcemia, hypothyroidism, uremia, and other metabolic derangements that
frequently cause delirium in older adults. Head CT is indicated if focal neurological deficits are present, and cardiac workup is
warranted if cardiac symptoms exist. Discharging without evaluation would miss potentially life-threatening and reversible
conditions.
Q6: Which statement best describes the concept of diagnostic timeout as recommended by the 2026 Joint
Commission National Patient Safety Goals for diagnostic safety?
A. A formal process where the diagnostic team pauses to review all collected data, consider alternative
diagnoses, and assess whether the working diagnosis adequately explains all findings **[CORRECT]**
B. A mandatory 24-hour observation period before any discharge from the emergency department to ensure diagnostic
stability
Page 3
, NR569 Midterm Exam | Differential Diagnosis in Acute Care Practicum 2026/2027 Update
C. A requirement that all imaging studies be reviewed by a radiologist before any treatment is initiated
D. A documentation requirement that forces the clinician to list at least 10 differential diagnoses for every patient
encounter
Correct Answer: A
Rationale: The diagnostic timeout is a structured cognitive strategy where clinicians pause to systematically review all available
data, consider whether the working diagnosis explains all findings, and actively explore alternative diagnoses. The 2026 Joint
Commission diagnostic safety goals emphasize this as a key strategy to reduce diagnostic errors. It is not a mandatory
observation period, radiology review requirement, or fixed number of differential diagnoses. Research published in JAMA in
2025 demonstrated that diagnostic timeouts reduced missed diagnoses by 23% in academic medical centers, making this an
evidence-based safety practice.
Q7: An ACNP is evaluating a patient with suspected acute coronary syndrome (ACS). The initial ECG shows
ST-segment depression in leads V1-V4. The troponin I is 0.08 ng/mL (99th percentile 0.04 ng/mL). According to the
2026 ACC/AHA guidelines for NSTEMI, which diagnostic or treatment action is most critical to perform within the
first 24 hours?
A. Obtain a cardiology consultation for elective cardiac catheterization within 72 hours
B. Initiate dual antiplatelet therapy, anticoagulation, and risk stratify using a validated scoring system such as
TIMI or GRACE **[CORRECT]**
C. Repeat troponin in 6 hours and discharge if stable with outpatient stress testing
D. Administer thrombolytic therapy given the ECG changes and elevated troponin
Correct Answer: B
Rationale: The 2026 ACC/AHA guidelines for NSTEMI management recommend early initiation of dual antiplatelet therapy
(aspirin plus a P2Y12 inhibitor), anticoagulation, and risk stratification using validated tools such as TIMI or GRACE scores.
High-risk patients (elevated troponin, dynamic ECG changes) should undergo early invasive strategy (cardiac catheterization
within 24 hours). Thrombolytic therapy is contraindicated in NSTEMI without ST elevation. Discharging an unstable patient
with elevated troponin without appropriate intervention would be dangerous. The combination of ST depression and elevated
troponin defines NSTEMI requiring urgent risk stratification and treatment.
Q8: A 35-year-old male presents with severe headache, photophobia, and neck stiffness. The ACNP suspects
meningitis. In the context of interprofessional collaboration, which action represents the most appropriate role of the
ACNP in the diagnostic process?
A. Order blood cultures and lumbar puncture independently without consulting other providers to expedite diagnosis
B. Initiate empiric antibiotics and dexamethasone, order blood cultures, then coordinate with neurology and
infectious disease for lumbar puncture timing **[CORRECT]**
C. Transfer the patient to the ICU immediately and defer all diagnostic decisions to the intensivist
D. Order an MRI brain before any other studies to rule out mass lesion before performing lumbar puncture
Correct Answer: B
Rationale: The 2026 Infectious Diseases Society of America (IDSA) meningitis guidelines recommend initiating empiric
antimicrobial therapy and dexamethasone as soon as meningitis is suspected, ideally after blood cultures but without delaying
treatment. The ACNP should coordinate with neurology and infectious disease specialists while maintaining ownership of the
initial stabilization and diagnostic process. Ordering LP independently without antimicrobial coverage risks delays if bacterial
meningitis is present. While ICU transfer may be needed, deferring all decisions is inappropriate. MRI is not routinely required
before LP unless focal neurological deficits or immunocompromised status is present.
Page 4
NR569 Differential Diagnosis in
Acute Care Practicum
2026/2027 Update | Weeks 1-4 Comprehensive Review | 90 Questions
Chamberlain College of Nursing
NR569: Differential Diagnosis in Acute Care Practicum
Verified Answers with Comprehensive Rationales
Cognitive Levels: 20% Recall | 45% Application | 35% Analysis
Question Types: 85% Scenario-Based (NGN-Enhanced) | 15% Direct Recall
,NR569 Midterm Exam | Differential Diagnosis in Acute Care Practicum 2026/2027 Update
Section 1: Foundations of Diagnostic Reasoning and Clinical Decision-Making
(Q1-Q12)
Q1: A 68-year-old male presents to the emergency department with acute onset chest pain. The ACNP begins
generating diagnostic hypotheses. Which approach best reflects the hypothesis-driven method of diagnostic reasoning
per 2026 guidelines?
A. Order a comprehensive metabolic panel and wait for results before forming any clinical impression
B. Generate multiple competing diagnoses simultaneously based on the initial presentation, then
systematically rule them in or out **[CORRECT]**
C. Rely solely on pattern recognition from previous similar patients to arrive at a single diagnosis immediately
D. Refer the patient to a specialist before initiating any diagnostic workup given the complexity
Correct Answer: B
Rationale: The hypothesis-driven method involves generating multiple diagnostic hypotheses early based on initial data, then
systematically testing each through focused assessment. This reduces cognitive bias and anchoring, which are leading causes of
diagnostic error in acute care per the 2026 National Academies of Medicine report. Option A delays clinical reasoning
inappropriately. Option C describes pattern recognition, prone to bias with atypical presentations. Option D defers reasoning
without initial assessment by the ACNP, which contradicts the scope of practice.
Q2: An ACNP evaluates a 55-year-old female with dyspnea. The Wells score estimates PE pre-test probability at
15%. A D-dimer returns at 450 ng/mL (negative below 500). Using Bayesian analysis, what is the most appropriate
next step?
A. Discharge the patient since the negative D-dimer conclusively rules out PE
B. Proceed directly to CTPA because the pre-test probability is too high for D-dimer
C. Calculate post-test probability using the negative likelihood ratio to determine if PE is excluded
**[CORRECT]**
D. Repeat the D-dimer in 24 hours to confirm the negative result before disposition
Correct Answer: C
Rationale: Bayesian analysis requires combining pre-test probability with test characteristics (likelihood ratios) to determine
post-test probability. The 2026 ACCP/ESC guidelines emphasize D-dimer interpretation must integrate clinical probability via
validated scoring. A D-dimer near the cutoff with moderate pre-test probability does not automatically exclude PE; the negative
likelihood ratio must be applied. If post-test probability remains above the test treatment threshold, further imaging is
warranted. Simply discharging or reflexively imaging both represent suboptimal diagnostic reasoning.
Q3: A 42-year-old female has 2 weeks of progressive fatigue, myalgias, and low-grade fevers. She was diagnosed with
viral syndrome 5 days ago but now presents with new petechiae on her lower extremities and gum bleeding. Which red
flag most significantly changes diagnostic urgency?
A. Duration of symptoms extending beyond 10 days without improvement
B. New onset bleeding manifestations suggesting a potential hematologic emergency **[CORRECT]**
C. Presence of myalgias which could indicate an autoimmune process
D. Low-grade fevers suggesting an undiagnosed infectious etiology requiring antibiotics
Correct Answer: B
Page 2
,NR569 Midterm Exam | Differential Diagnosis in Acute Care Practicum 2026/2027 Update
Rationale: New bleeding manifestations with progressive constitutional symptoms is a critical red flag dramatically shifting
diagnostic urgency. This suggests thrombocytopenia with bleeding risk, potentially indicating acute leukemia, aplastic anemia,
DIC, or severe sepsis. The 2026 NCCN and ASH guidelines emphasize new bleeding with systemic symptoms requires immediate
CBC with differential, coagulation studies, and peripheral smear. While duration, myalgias, and fevers are concerning, they
represent gradual progression rather than acute change signaling life-threatening pathology.
Q4: In the NGN Clinical Judgment Measurement Model (CJMM), which action best represents the "Analyze Cues"
step when a 75-year-old presents with confusion, hypotension (BP 88/50), and temperature 38.9 degrees Celsius?
A. Immediately administer broad-spectrum antibiotics and isotonic IV fluids
B. Recognize that the combination of altered mental status, hemodynamic instability, and fever form a cluster
suggesting sepsis **[CORRECT]**
C. Prioritize which diagnosis is most likely before obtaining additional clinical data
D. Evaluate the patient response to initial fluid resuscitation after 30 minutes
Correct Answer: B
Rationale: The Analyze Cues step in the CJMM involves recognizing patterns and relationships among clinical data to identify
clinical significance. In this scenario, the cluster of confusion (altered mental status), hypotension (hemodynamic instability),
and fever forms a recognizable pattern consistent with sepsis per Sepsis-3 criteria. Option A represents "Take Action," which
occurs after analysis and prioritization. Option C represents "Prioritize Hypotheses," which follows analysis. Option D represents
"Evaluate Outcomes," the final step. The 2026 NCSBN framework emphasizes that analyzing cues must precede generating
solutions or taking action.
Q5: An ACNP is caring for an 80-year-old female who presents with generalized weakness and falls over the past
week. Her vital signs are BP 130/80, HR 78, RR 16, T 37.0 degrees C, SpO2 97%. Her family reports she seems more
confused than usual. Which diagnostic testing strategy is most appropriate as the initial step?
A. Order a head CT immediately to evaluate for intracranial pathology given the confusion and falls
B. Obtain a comprehensive metabolic panel including calcium, TSH, and vitamin B12 level as the initial
diagnostic step **[CORRECT]**
C. Order a full cardiac workup including echocardiogram and Holter monitor given the nonspecific presentation in the
elderly
D. Discharge with physical therapy referral as this is a normal age-related decline in functional status
Correct Answer: B
Rationale: In elderly patients, altered mental status and generalized weakness have broad differential diagnoses, with metabolic
causes being among the most common and reversible. The 2026 American Geriatrics Society guidelines recommend initial
evaluation with comprehensive metabolic panel including electrolytes, glucose, renal function, calcium, TSH, and vitamin B12.
These tests can identify hyponatremia, hypercalcemia, hypothyroidism, uremia, and other metabolic derangements that
frequently cause delirium in older adults. Head CT is indicated if focal neurological deficits are present, and cardiac workup is
warranted if cardiac symptoms exist. Discharging without evaluation would miss potentially life-threatening and reversible
conditions.
Q6: Which statement best describes the concept of diagnostic timeout as recommended by the 2026 Joint
Commission National Patient Safety Goals for diagnostic safety?
A. A formal process where the diagnostic team pauses to review all collected data, consider alternative
diagnoses, and assess whether the working diagnosis adequately explains all findings **[CORRECT]**
B. A mandatory 24-hour observation period before any discharge from the emergency department to ensure diagnostic
stability
Page 3
, NR569 Midterm Exam | Differential Diagnosis in Acute Care Practicum 2026/2027 Update
C. A requirement that all imaging studies be reviewed by a radiologist before any treatment is initiated
D. A documentation requirement that forces the clinician to list at least 10 differential diagnoses for every patient
encounter
Correct Answer: A
Rationale: The diagnostic timeout is a structured cognitive strategy where clinicians pause to systematically review all available
data, consider whether the working diagnosis explains all findings, and actively explore alternative diagnoses. The 2026 Joint
Commission diagnostic safety goals emphasize this as a key strategy to reduce diagnostic errors. It is not a mandatory
observation period, radiology review requirement, or fixed number of differential diagnoses. Research published in JAMA in
2025 demonstrated that diagnostic timeouts reduced missed diagnoses by 23% in academic medical centers, making this an
evidence-based safety practice.
Q7: An ACNP is evaluating a patient with suspected acute coronary syndrome (ACS). The initial ECG shows
ST-segment depression in leads V1-V4. The troponin I is 0.08 ng/mL (99th percentile 0.04 ng/mL). According to the
2026 ACC/AHA guidelines for NSTEMI, which diagnostic or treatment action is most critical to perform within the
first 24 hours?
A. Obtain a cardiology consultation for elective cardiac catheterization within 72 hours
B. Initiate dual antiplatelet therapy, anticoagulation, and risk stratify using a validated scoring system such as
TIMI or GRACE **[CORRECT]**
C. Repeat troponin in 6 hours and discharge if stable with outpatient stress testing
D. Administer thrombolytic therapy given the ECG changes and elevated troponin
Correct Answer: B
Rationale: The 2026 ACC/AHA guidelines for NSTEMI management recommend early initiation of dual antiplatelet therapy
(aspirin plus a P2Y12 inhibitor), anticoagulation, and risk stratification using validated tools such as TIMI or GRACE scores.
High-risk patients (elevated troponin, dynamic ECG changes) should undergo early invasive strategy (cardiac catheterization
within 24 hours). Thrombolytic therapy is contraindicated in NSTEMI without ST elevation. Discharging an unstable patient
with elevated troponin without appropriate intervention would be dangerous. The combination of ST depression and elevated
troponin defines NSTEMI requiring urgent risk stratification and treatment.
Q8: A 35-year-old male presents with severe headache, photophobia, and neck stiffness. The ACNP suspects
meningitis. In the context of interprofessional collaboration, which action represents the most appropriate role of the
ACNP in the diagnostic process?
A. Order blood cultures and lumbar puncture independently without consulting other providers to expedite diagnosis
B. Initiate empiric antibiotics and dexamethasone, order blood cultures, then coordinate with neurology and
infectious disease for lumbar puncture timing **[CORRECT]**
C. Transfer the patient to the ICU immediately and defer all diagnostic decisions to the intensivist
D. Order an MRI brain before any other studies to rule out mass lesion before performing lumbar puncture
Correct Answer: B
Rationale: The 2026 Infectious Diseases Society of America (IDSA) meningitis guidelines recommend initiating empiric
antimicrobial therapy and dexamethasone as soon as meningitis is suspected, ideally after blood cultures but without delaying
treatment. The ACNP should coordinate with neurology and infectious disease specialists while maintaining ownership of the
initial stabilization and diagnostic process. Ordering LP independently without antimicrobial coverage risks delays if bacterial
meningitis is present. While ICU transfer may be needed, deferring all decisions is inappropriate. MRI is not routinely required
before LP unless focal neurological deficits or immunocompromised status is present.
Page 4
