Adult-Gerontology CNS Test Clinical Assessment & Diagnosis 2 — Questions and Answers
Question 1: The ankle-brachial index (ABI) value diagnostic of significant peripheral arterial disease is:
- Greater than 1.3
- 0.9 or less (Correct answer)
- 1.0 to 1.2
- 0.5 to 0.7 only with symptoms
Correct answer: 0.9 or less
An ABI of 0.9 or less indicates arterial obstruction reducing ankle pressures relative to brachial pressure, confirming hemodynamically significant PAD.
Question 2: The most sensitive early indicator of acute kidney injury is:
- Serum BUN elevation
- Rise in serum creatinine by 0.3 mg/dL or more within 48 hours or 1.5× baseline within 7 days (Correct answer)
- Oliguria lasting more than 12 hours
- Hematuria on urinalysis
Correct answer: Rise in serum creatinine by 0.3 mg/dL or more within 48 hours or 1.5× baseline within 7 days
The KDIGO AKI definition uses creatinine rise thresholds because small absolute increases early in AKI reflect significant GFR decline before BUN or symptoms appear.
Question 3: On auscultation, a harsh systolic ejection murmur radiating to the carotids in an older adult most suggests:
- Mitral regurgitation
- Aortic stenosis (Correct answer)
- Pulmonary stenosis
- Ventricular septal defect
Correct answer: Aortic stenosis
Aortic stenosis produces a harsh crescendo-decrescendo systolic murmur at the right upper sternal border that radiates to the carotid arteries due to high-velocity turbulent flow.
Question 4: Kussmaul breathing, the deep, labored respiratory pattern, is a clinical sign of:
- Pulmonary embolism causing hypoxia
- Severe metabolic acidosis requiring respiratory compensation (Correct answer)
- Hyperventilation syndrome from anxiety
- Obstructive sleep apnea
Correct answer: Severe metabolic acidosis requiring respiratory compensation
Kussmaul respirations represent the body's maximal effort to lower PaCO2 through increased minute ventilation to compensate for severe metabolic acidosis (e.g., DKA, uremia).
Question 5: Thyroid-stimulating hormone (TSH) is the most sensitive test for screening thyroid dysfunction because:
- TSH directly measures thyroid hormone production
- Pituitary TSH responds exponentially to small changes in free T4 and T3 levels (Correct answer)
- TSH testing is less expensive than free T4 measurement
- TSH reflects tissue-level thyroid hormone activity
Correct answer: Pituitary TSH responds exponentially to small changes in free T4 and T3 levels
The pituitary's log-linear feedback amplifies small changes in circulating thyroid hormones into large TSH changes, making TSH far more sensitive than direct hormone measurement.
Question 6: The Confusion Assessment Method (CAM) is used to diagnose:
- Chronic dementia in community-dwelling older adults
- Delirium in hospitalized patients based on four core features (Correct answer)
- Depression severity in post-operative patients
- Medication-induced cognitive impairment
Correct answer: Delirium in hospitalized patients based on four core features
CAM identifies delirium by confirming acute onset with fluctuating course, inattention, and either disorganized thinking or altered level of consciousness.
Adult-Gerontology CNS Test Clinical Assessment & Diagnosis 2
The ankle-brachial index (ABI) value diagnostic of significant peripheral arterial disease is: