2026 AGACNP-BC Exam Prep: Adult-
Gerontology Acute Care Practice Questions with
Answer Rationales for Critical Care, Diagnostics,
Pharmacology, Acute Conditions, Clinical
Management, and Study Guide
Domain 1: Assessment and Diagnosis (30% of Scored Exam)
Q1. A 68-year-old male is admitted to the ICU with acute respiratory distress. His
ABG shows pH 7.28, PaCO₂ 58 mmHg, and HCO₃⁻ 26 mEq/L. What is the most
likely acid-base disturbance?
A. Metabolic acidosis
B. Respiratory acidosis
C. Metabolic alkalosis
D. Respiratory alkalosis
Answer: B
Rationale: Uncompensated respiratory acidosis is characterized by a low pH
(<7.35) and elevated PaCO₂ (>45 mmHg) with a normal bicarbonate level. The
elevated PaCO₂ indicates alveolar hypoventilation, which can be caused by COPD
exacerbation, sedation, or neuromuscular disease .
Q2. A 72-year-old female presents with sudden onset of severe headache, neck
stiffness, and photophobia. What is the most likely diagnosis?
A. Migraine
B. Subarachnoid hemorrhage
C. Tension headache
D. Meningitis
Answer: B
Rationale: The "thunderclap" headache with meningismus is classic for
subarachnoid hemorrhage. Meningitis also presents with neck stiffness and
,photophobia but typically has fever and a more gradual onset. Migraine and
tension headache do not present with neck stiffness.
Q3. A 65-year-old patient has a CHA₂DS₂-VASc score of 4 with new atrial
fibrillation. Which is the most appropriate stroke prevention strategy?
A. Aspirin 81 mg daily
B. Anticoagulation with a direct oral anticoagulant (DOAC) or warfarin
C. No antithrombotic therapy
D. Clopidogrel 75 mg daily
Answer: B
Rationale: A CHA₂DS₂-VASc score of ≥2 in men (or ≥3 in women) warrants oral
anticoagulation. DOACs are preferred over warfarin in most patients without
mechanical valves or severe mitral stenosis. Aspirin and clopidogrel are not
adequate for stroke prevention in high-risk AF.
Q4. A 70-year-old patient with COPD has an SpO₂ of 88% on room air. What is
the most appropriate initial intervention?
A. Administer high-flow oxygen at 10 L/min
B. Administer low-flow oxygen at 2 L/min and titrate to SpO₂ 88–92%
C. No oxygen supplementation needed
D. Intubate immediately
Answer: B
Rationale: In COPD with chronic CO₂ retention, the target SpO₂ is 88–92%. High-
flow oxygen can worsen hypercapnia by suppressing respiratory drive. Intubation
is not indicated for an SpO₂ of 88% without other signs of respiratory failure.
Q5. A 72-year-old patient presents with a Mini-Cog score of 2/5. What is the most
appropriate next step?
A. Diagnose dementia and start donepezil
B. Perform a comprehensive cognitive assessment and workup
,C. Reassure the patient that this is normal aging
D. Order a head CT only
Answer: B
Rationale: A Mini-Cog score of ≤3 suggests cognitive impairment and warrants a
comprehensive assessment to identify reversible causes and determine the
underlying etiology. Diagnosis of dementia requires more than a screening test,
and a score of 2/5 is not normal aging.
Q6. A 75-year-old patient presents with new-onset atrial fibrillation and a heart
rate of 140 bpm. Which assessment finding is most concerning for hemodynamic
instability?
A. Blood pressure 110/70 mmHg
B. Altered mental status
C. Heart rate 140 bpm
D. Patient reports palpitations
Answer: B
Rationale: Altered mental status indicates cerebral hypoperfusion and is a sign of
hemodynamic instability requiring urgent intervention. Hypotension would also be
concerning, but a BP of 110/70 is acceptable. Palpitations are expected with rapid
AF.
Q7. Which laboratory value is most indicative of early renal impairment in an
older adult?
A. Serum sodium 138 mmol/L
B. Blood urea nitrogen 28 mg/dL
C. Creatinine clearance 70 mL/min
D. Glomerular filtration rate 55 mL/min/1.73 m²
Answer: D
Rationale: GFR accounts for age-related muscle mass loss; a value <60
mL/min/1.73 m² signals chronic kidney disease. Serum sodium is within normal
, limits, BUN is nonspecific, and creatinine clearance overestimates renal function
in older adults due to reduced muscle mass.
Q8. A 78-year-old patient has a creatinine of 2.0 mg/dL. Which factor most affects
the interpretation of this value?
A. The patient's age
B. The patient's muscle mass
C. The patient's hydration status
D. All of the above
Answer: D
Rationale: Serum creatinine is affected by age (reduced renal function), muscle
mass (reduced in frail elderly), and hydration status. All must be considered when
interpreting creatinine values in older adults.
Q9. A 70-year-old patient has a hemoglobin of 9.5 g/dL and MCV of 72 fL. What
is the most likely cause?
A. Vitamin B12 deficiency
B. Iron deficiency anemia
C. Folate deficiency
D. Anemia of chronic disease
Answer: B
Rationale: Microcytic anemia (MCV <80 fL) with low hemoglobin is most
commonly caused by iron deficiency. Vitamin B12 and folate deficiencies cause
macrocytic anemia. Anemia of chronic disease is typically normocytic.
Q10. A 78-year-old patient with heart failure has a BNP of 850 pg/mL. What does
this value most likely indicate?
A. Normal cardiac function
B. Compensated heart failure
C. Decompensated heart failure
D. Pulmonary embolism
Gerontology Acute Care Practice Questions with
Answer Rationales for Critical Care, Diagnostics,
Pharmacology, Acute Conditions, Clinical
Management, and Study Guide
Domain 1: Assessment and Diagnosis (30% of Scored Exam)
Q1. A 68-year-old male is admitted to the ICU with acute respiratory distress. His
ABG shows pH 7.28, PaCO₂ 58 mmHg, and HCO₃⁻ 26 mEq/L. What is the most
likely acid-base disturbance?
A. Metabolic acidosis
B. Respiratory acidosis
C. Metabolic alkalosis
D. Respiratory alkalosis
Answer: B
Rationale: Uncompensated respiratory acidosis is characterized by a low pH
(<7.35) and elevated PaCO₂ (>45 mmHg) with a normal bicarbonate level. The
elevated PaCO₂ indicates alveolar hypoventilation, which can be caused by COPD
exacerbation, sedation, or neuromuscular disease .
Q2. A 72-year-old female presents with sudden onset of severe headache, neck
stiffness, and photophobia. What is the most likely diagnosis?
A. Migraine
B. Subarachnoid hemorrhage
C. Tension headache
D. Meningitis
Answer: B
Rationale: The "thunderclap" headache with meningismus is classic for
subarachnoid hemorrhage. Meningitis also presents with neck stiffness and
,photophobia but typically has fever and a more gradual onset. Migraine and
tension headache do not present with neck stiffness.
Q3. A 65-year-old patient has a CHA₂DS₂-VASc score of 4 with new atrial
fibrillation. Which is the most appropriate stroke prevention strategy?
A. Aspirin 81 mg daily
B. Anticoagulation with a direct oral anticoagulant (DOAC) or warfarin
C. No antithrombotic therapy
D. Clopidogrel 75 mg daily
Answer: B
Rationale: A CHA₂DS₂-VASc score of ≥2 in men (or ≥3 in women) warrants oral
anticoagulation. DOACs are preferred over warfarin in most patients without
mechanical valves or severe mitral stenosis. Aspirin and clopidogrel are not
adequate for stroke prevention in high-risk AF.
Q4. A 70-year-old patient with COPD has an SpO₂ of 88% on room air. What is
the most appropriate initial intervention?
A. Administer high-flow oxygen at 10 L/min
B. Administer low-flow oxygen at 2 L/min and titrate to SpO₂ 88–92%
C. No oxygen supplementation needed
D. Intubate immediately
Answer: B
Rationale: In COPD with chronic CO₂ retention, the target SpO₂ is 88–92%. High-
flow oxygen can worsen hypercapnia by suppressing respiratory drive. Intubation
is not indicated for an SpO₂ of 88% without other signs of respiratory failure.
Q5. A 72-year-old patient presents with a Mini-Cog score of 2/5. What is the most
appropriate next step?
A. Diagnose dementia and start donepezil
B. Perform a comprehensive cognitive assessment and workup
,C. Reassure the patient that this is normal aging
D. Order a head CT only
Answer: B
Rationale: A Mini-Cog score of ≤3 suggests cognitive impairment and warrants a
comprehensive assessment to identify reversible causes and determine the
underlying etiology. Diagnosis of dementia requires more than a screening test,
and a score of 2/5 is not normal aging.
Q6. A 75-year-old patient presents with new-onset atrial fibrillation and a heart
rate of 140 bpm. Which assessment finding is most concerning for hemodynamic
instability?
A. Blood pressure 110/70 mmHg
B. Altered mental status
C. Heart rate 140 bpm
D. Patient reports palpitations
Answer: B
Rationale: Altered mental status indicates cerebral hypoperfusion and is a sign of
hemodynamic instability requiring urgent intervention. Hypotension would also be
concerning, but a BP of 110/70 is acceptable. Palpitations are expected with rapid
AF.
Q7. Which laboratory value is most indicative of early renal impairment in an
older adult?
A. Serum sodium 138 mmol/L
B. Blood urea nitrogen 28 mg/dL
C. Creatinine clearance 70 mL/min
D. Glomerular filtration rate 55 mL/min/1.73 m²
Answer: D
Rationale: GFR accounts for age-related muscle mass loss; a value <60
mL/min/1.73 m² signals chronic kidney disease. Serum sodium is within normal
, limits, BUN is nonspecific, and creatinine clearance overestimates renal function
in older adults due to reduced muscle mass.
Q8. A 78-year-old patient has a creatinine of 2.0 mg/dL. Which factor most affects
the interpretation of this value?
A. The patient's age
B. The patient's muscle mass
C. The patient's hydration status
D. All of the above
Answer: D
Rationale: Serum creatinine is affected by age (reduced renal function), muscle
mass (reduced in frail elderly), and hydration status. All must be considered when
interpreting creatinine values in older adults.
Q9. A 70-year-old patient has a hemoglobin of 9.5 g/dL and MCV of 72 fL. What
is the most likely cause?
A. Vitamin B12 deficiency
B. Iron deficiency anemia
C. Folate deficiency
D. Anemia of chronic disease
Answer: B
Rationale: Microcytic anemia (MCV <80 fL) with low hemoglobin is most
commonly caused by iron deficiency. Vitamin B12 and folate deficiencies cause
macrocytic anemia. Anemia of chronic disease is typically normocytic.
Q10. A 78-year-old patient with heart failure has a BNP of 850 pg/mL. What does
this value most likely indicate?
A. Normal cardiac function
B. Compensated heart failure
C. Decompensated heart failure
D. Pulmonary embolism
