NURS 231 Pathophysiology | Portage Learning | Final Exam
2026/2027 Complete Final Examination | Actual Questions &
Verified Answers | Comprehensive Pathophysiology
Assessment | Pass Guarantee
1. A 68-year-old man with a 40-pack-year history has long-standing COPD. Arterial
blood gases on 2 L NC show pH 7.32, PaCO₂ 68 mmHg, HCO₃⁻ 38 mEq/L, PaO₂
58 mmHg. Which cellular adaptation in his central neurons is MOST responsible
for the pH being only mildly decreased despite marked hypercapnia?
A. Shift of Cl⁻ into cells to buffer H⁺
B. Increased renal synthesis of ammonia
C. Intracellular generation of bicarbonate over 2–3 days
D. Up-regulation of Na⁺/H⁺ exchangers in the BBB
Correct Answer: C
Rationale: Chronic hypercapnia allows central chemoreceptors time (24–48 h) to
generate intracellular bicarbonate, returning pH toward normal and blunting ventilatory
drive; this is “metabolic compensation” at the cellular level. Choices A & D are acute, not
adaptive. B is renal, not neural.
2. A patient with CKD (GFR 18 mL/min) develops metabolic acidosis. Which
skeletal manifestation is MOST directly linked to the buffering action of bone?
A. Osteosarcoma
B. Osteomalacia
C. Osteomyelitis
D. Paget disease
Correct Answer: B
,Rationale: Chronic acidemia forces bone to release carbonate/phosphate buffers,
solubilizing mineral → defective mineralization (osteomalacia). Others are infectious or
neoplastic.
3. In hemorrhagic shock, which change best indicates transition from compensated
to de-compensated (progressive) shock?
A. Serum lactate 2.1 mmol/L
B. Urine output 35 mL/h
C. Systolic BP falls from 110 to 78 mmHg
D. Respiratory rate 24/min
Correct Answer: C
Rationale: Compensated shock maintains BP via vasoconstriction; falling SBP marks
de-compensation. Lactate 2–4 mmol/L and mild tachypnea/tachycardia still represent
compensation.
4. A patient with severe acute pancreatitis develops tetany and carpal spasm 24 h
after admission. Ca²⁺ 6.8 mg/dL (normal 8.5–10.5). Which mediator MOST
directly lowers ionized calcium?
A. Bradykinin
B. Lipase
C. Free fatty acids that chelate calcium
D. Complement C5a
Correct Answer: C
Rationale: Lipase hydrolyzes triglycerides → free fatty acids; these bind Ca²⁺, lowering
ionized level and causing clinical hypocalcemia.
5. A 58-year-old woman with NYHA class-IV heart failure is started on high-dose
furosemide and develops muscle weakness, palpitations, and flattened T-waves
on ECG. K⁺ 2.6 mEq/L. Which mechanism BEST explains flattened T-waves?
A. Prolonged phase-0 Na⁺ influx
, B. Decreased phase-2 K⁺ efflux
C. Slowed phase-4 spontaneous depolarization
D. Early after-depolarizations
Correct Answer: B
Rationale: Hypokalemia reduces outward K⁺ current during plateau (phase-2), flattening
repolarization (T-wave). Phase-0 (A) relates to Na⁺ and QRS; phase-4 (C) to automaticity;
EADs (D) cause prolonged QT, not flat T.
6. Which set of arterial blood values indicates a primary respiratory alkalosis with
partial metabolic compensation?
A. pH 7.48, PaCO₂ 30, HCO₃⁻ 20
B. pH 7.36, PaCO₂ 55, HCO₃⁻ 32
C. pH 7.28, PaCO₂ 60, HCO₃⁻ 28
D. pH 7.52, PaCO₂ 46, HCO₃⁻ 36
Correct Answer: A
Rationale: High pH, low PaCO₂ = primary respiratory alkalosis; HCO₃⁻ dropped 4 mEq
(expected ↓ 5 for PaCO₂ 10 ↓) = appropriate renal compensation.
7. A patient with septic shock receives 4 L crystalloid but remains hypotensive.
MAP 55 mmHg, CVP 14 mmHg, ScvO₂ 78 %. Which pathophysiologic process
BEST explains the high ScvO₂?
A. Increased O₂ extraction
B. Mitochondrial dysfunction (cytopathic hypoxia)
C. Arteriovenous shunting due to vasodilation
D. Both B & C
Correct Answer: D
Rationale: In sepsis, inflammatory mediators impair cellular O₂ use (cytopathic hypoxia)
and create microvascular shunts → venous saturation rises despite global hypoxia.
, 8. A 72-year-old man with Alzheimer disease is admitted with pneumonia. His
daughter asks why he becomes agitated every evening. Which neurotransmitter
imbalance BEST explains sundowning?
A. ↓ Dopamine in substantia nigra
B. ↓ Acetylcholine + ↑ cortisol at night
C. ↑ Serotonin in raphe nuclei
D. ↑ GABA in hippocampus
Correct Answer: B
Rationale: Degeneration of cholinergic neurons (basal forebrain) impairs attention;
evening cortisol surge further disrupts cognition → agitation.
9. A patient with TBI (coup-contrecoup) develops SIADH. Which cellular change
occurs in neurons as hyponatremia (< 125 mEq/L) progresses?
A. Potassium shifts extracellularly
B. Osmotic swelling → loss of intracellular osmolytes
C. Calcium influx → apoptosis
D. Glycogen depletion
Correct Answer: B
Rationale: Hypotonicity drives water into cells; brain cells counteract by exporting K⁺,
Cl⁻, organic osmolytes to limit swelling.
10. A 60-pack-year smoker has chronic bronchitis. Which inflammatory cell type
predominates in his airway walls and MOST directly drives mucus
hypersecretion?
A. Eosinophils
B. Neutrophils (via elastase)
C. Mast cells
D. TH2 lymphocytes
Correct Answer: B
2026/2027 Complete Final Examination | Actual Questions &
Verified Answers | Comprehensive Pathophysiology
Assessment | Pass Guarantee
1. A 68-year-old man with a 40-pack-year history has long-standing COPD. Arterial
blood gases on 2 L NC show pH 7.32, PaCO₂ 68 mmHg, HCO₃⁻ 38 mEq/L, PaO₂
58 mmHg. Which cellular adaptation in his central neurons is MOST responsible
for the pH being only mildly decreased despite marked hypercapnia?
A. Shift of Cl⁻ into cells to buffer H⁺
B. Increased renal synthesis of ammonia
C. Intracellular generation of bicarbonate over 2–3 days
D. Up-regulation of Na⁺/H⁺ exchangers in the BBB
Correct Answer: C
Rationale: Chronic hypercapnia allows central chemoreceptors time (24–48 h) to
generate intracellular bicarbonate, returning pH toward normal and blunting ventilatory
drive; this is “metabolic compensation” at the cellular level. Choices A & D are acute, not
adaptive. B is renal, not neural.
2. A patient with CKD (GFR 18 mL/min) develops metabolic acidosis. Which
skeletal manifestation is MOST directly linked to the buffering action of bone?
A. Osteosarcoma
B. Osteomalacia
C. Osteomyelitis
D. Paget disease
Correct Answer: B
,Rationale: Chronic acidemia forces bone to release carbonate/phosphate buffers,
solubilizing mineral → defective mineralization (osteomalacia). Others are infectious or
neoplastic.
3. In hemorrhagic shock, which change best indicates transition from compensated
to de-compensated (progressive) shock?
A. Serum lactate 2.1 mmol/L
B. Urine output 35 mL/h
C. Systolic BP falls from 110 to 78 mmHg
D. Respiratory rate 24/min
Correct Answer: C
Rationale: Compensated shock maintains BP via vasoconstriction; falling SBP marks
de-compensation. Lactate 2–4 mmol/L and mild tachypnea/tachycardia still represent
compensation.
4. A patient with severe acute pancreatitis develops tetany and carpal spasm 24 h
after admission. Ca²⁺ 6.8 mg/dL (normal 8.5–10.5). Which mediator MOST
directly lowers ionized calcium?
A. Bradykinin
B. Lipase
C. Free fatty acids that chelate calcium
D. Complement C5a
Correct Answer: C
Rationale: Lipase hydrolyzes triglycerides → free fatty acids; these bind Ca²⁺, lowering
ionized level and causing clinical hypocalcemia.
5. A 58-year-old woman with NYHA class-IV heart failure is started on high-dose
furosemide and develops muscle weakness, palpitations, and flattened T-waves
on ECG. K⁺ 2.6 mEq/L. Which mechanism BEST explains flattened T-waves?
A. Prolonged phase-0 Na⁺ influx
, B. Decreased phase-2 K⁺ efflux
C. Slowed phase-4 spontaneous depolarization
D. Early after-depolarizations
Correct Answer: B
Rationale: Hypokalemia reduces outward K⁺ current during plateau (phase-2), flattening
repolarization (T-wave). Phase-0 (A) relates to Na⁺ and QRS; phase-4 (C) to automaticity;
EADs (D) cause prolonged QT, not flat T.
6. Which set of arterial blood values indicates a primary respiratory alkalosis with
partial metabolic compensation?
A. pH 7.48, PaCO₂ 30, HCO₃⁻ 20
B. pH 7.36, PaCO₂ 55, HCO₃⁻ 32
C. pH 7.28, PaCO₂ 60, HCO₃⁻ 28
D. pH 7.52, PaCO₂ 46, HCO₃⁻ 36
Correct Answer: A
Rationale: High pH, low PaCO₂ = primary respiratory alkalosis; HCO₃⁻ dropped 4 mEq
(expected ↓ 5 for PaCO₂ 10 ↓) = appropriate renal compensation.
7. A patient with septic shock receives 4 L crystalloid but remains hypotensive.
MAP 55 mmHg, CVP 14 mmHg, ScvO₂ 78 %. Which pathophysiologic process
BEST explains the high ScvO₂?
A. Increased O₂ extraction
B. Mitochondrial dysfunction (cytopathic hypoxia)
C. Arteriovenous shunting due to vasodilation
D. Both B & C
Correct Answer: D
Rationale: In sepsis, inflammatory mediators impair cellular O₂ use (cytopathic hypoxia)
and create microvascular shunts → venous saturation rises despite global hypoxia.
, 8. A 72-year-old man with Alzheimer disease is admitted with pneumonia. His
daughter asks why he becomes agitated every evening. Which neurotransmitter
imbalance BEST explains sundowning?
A. ↓ Dopamine in substantia nigra
B. ↓ Acetylcholine + ↑ cortisol at night
C. ↑ Serotonin in raphe nuclei
D. ↑ GABA in hippocampus
Correct Answer: B
Rationale: Degeneration of cholinergic neurons (basal forebrain) impairs attention;
evening cortisol surge further disrupts cognition → agitation.
9. A patient with TBI (coup-contrecoup) develops SIADH. Which cellular change
occurs in neurons as hyponatremia (< 125 mEq/L) progresses?
A. Potassium shifts extracellularly
B. Osmotic swelling → loss of intracellular osmolytes
C. Calcium influx → apoptosis
D. Glycogen depletion
Correct Answer: B
Rationale: Hypotonicity drives water into cells; brain cells counteract by exporting K⁺,
Cl⁻, organic osmolytes to limit swelling.
10. A 60-pack-year smoker has chronic bronchitis. Which inflammatory cell type
predominates in his airway walls and MOST directly drives mucus
hypersecretion?
A. Eosinophils
B. Neutrophils (via elastase)
C. Mast cells
D. TH2 lymphocytes
Correct Answer: B
