WGU D236 Pathophysiology Practice
Assessment - 2026/2027 Competency Alignment
| Mastery Preparation | Disease Process
Evaluation
Domain 1: Foundational Pathophysiological Principles (Cellular Injury, Fluids,
Acid-Base, Genetics, Stress)
Q1. A 68-year-old patient with chronic renal failure is most likely to experience which
type of acid-base imbalance? What is the primary physiological reason?
A. Respiratory Acidosis; decreased CO₂ excretion.
B. Metabolic Alkalosis; increased bicarbonate retention.
C. Metabolic Acidosis; decreased excretion of hydrogen ions and decreased production
of bicarbonate.
D. Respiratory Alkalosis; hyperventilation due to anemia.
Verified Answer: C
Rationale: In chronic renal failure the kidneys cannot excrete H⁺ or regenerate HCO₃⁻ →
non-anion-gap metabolic acidosis. Choices A, B, and D involve respiratory causes or
alkalosis – not the primary defect.
Q2. A patient with SIADH is admitted. Which set of lab values would the nurse
anticipate?
,A. Serum Na⁺ 128 mmol/L, serum osmolality 260 mOsm/kg, urine osmolality 450
mOsm/kg
B. Serum Na⁺ 150 mmol/L, serum osmolality 300 mOsm/kg, urine osmolality 100
mOsm/kg
C. Serum K⁺ 3.0 mmol/L, serum osmolality 295 mOsm/kg, urine osmolality 800
mOsm/kg
D. Serum Na⁺ 140 mmol/L, serum osmolality 285 mOsm/kg, urine osmolality 300
mOsm/kg
Verified Answer: A
Rationale: SIADH = excess ADH → water retention, dilutional hyponatremia, low serum
osmolality, inappropriately high urine osmolality (A). B = hypernatremia, C =
hypokalemia, D = normal values.
Q3. A patient with Cushing syndrome is at highest risk for which electrolyte imbalance?
A. Hypokalemia
B. Hypernatremia
C. Hypocalcemia
D. Hyperphosphatemia
Verified Answer: A
Rationale: Excess cortisol promotes renal K⁺ wasting → hypokalemia (A); mild Na⁺
retention occurs but K⁺ loss is clinically significant.
, Q4. A burn patient develops compartment syndrome of the forearm. The
pathophysiological mechanism is:
A. Vasodilation leading to increased capillary permeability and interstitial edema.
B. Intracellular potassium loss causing muscle weakness.
C. Edema within a closed fascial space causing venous congestion & ischemia.
D. Coagulation necrosis from direct thermal injury.
Verified Answer: C
Rationale: Compartment syndrome = increased pressure within a closed fascial space
→ venous outflow obstruction → ischemia & necrosis (C). A describes early burn
edema, D describes third-degree burn, B is unrelated.
Q5. A patient with sickle-cell disease in vaso-occlusive crisis has severe pain. The initial
cellular event is:
A. Auto-antibody binding to red-cell membrane
B. Hemoglobin S polymerization under hypoxia → rigid sickled cells → microvascular
occlusion
C. Bone-marrow aplasia from parvovirus B19
D. Iron overload from transfusions
Verified Answer: B
Rationale: Hypoxia → HbS polymerization → rigid sickle-shaped RBCs → microvascular
occlusion & pain (B). A = autoimmune hemolysis, C = aplastic crisis, D = transfusion
siderosis.
Assessment - 2026/2027 Competency Alignment
| Mastery Preparation | Disease Process
Evaluation
Domain 1: Foundational Pathophysiological Principles (Cellular Injury, Fluids,
Acid-Base, Genetics, Stress)
Q1. A 68-year-old patient with chronic renal failure is most likely to experience which
type of acid-base imbalance? What is the primary physiological reason?
A. Respiratory Acidosis; decreased CO₂ excretion.
B. Metabolic Alkalosis; increased bicarbonate retention.
C. Metabolic Acidosis; decreased excretion of hydrogen ions and decreased production
of bicarbonate.
D. Respiratory Alkalosis; hyperventilation due to anemia.
Verified Answer: C
Rationale: In chronic renal failure the kidneys cannot excrete H⁺ or regenerate HCO₃⁻ →
non-anion-gap metabolic acidosis. Choices A, B, and D involve respiratory causes or
alkalosis – not the primary defect.
Q2. A patient with SIADH is admitted. Which set of lab values would the nurse
anticipate?
,A. Serum Na⁺ 128 mmol/L, serum osmolality 260 mOsm/kg, urine osmolality 450
mOsm/kg
B. Serum Na⁺ 150 mmol/L, serum osmolality 300 mOsm/kg, urine osmolality 100
mOsm/kg
C. Serum K⁺ 3.0 mmol/L, serum osmolality 295 mOsm/kg, urine osmolality 800
mOsm/kg
D. Serum Na⁺ 140 mmol/L, serum osmolality 285 mOsm/kg, urine osmolality 300
mOsm/kg
Verified Answer: A
Rationale: SIADH = excess ADH → water retention, dilutional hyponatremia, low serum
osmolality, inappropriately high urine osmolality (A). B = hypernatremia, C =
hypokalemia, D = normal values.
Q3. A patient with Cushing syndrome is at highest risk for which electrolyte imbalance?
A. Hypokalemia
B. Hypernatremia
C. Hypocalcemia
D. Hyperphosphatemia
Verified Answer: A
Rationale: Excess cortisol promotes renal K⁺ wasting → hypokalemia (A); mild Na⁺
retention occurs but K⁺ loss is clinically significant.
, Q4. A burn patient develops compartment syndrome of the forearm. The
pathophysiological mechanism is:
A. Vasodilation leading to increased capillary permeability and interstitial edema.
B. Intracellular potassium loss causing muscle weakness.
C. Edema within a closed fascial space causing venous congestion & ischemia.
D. Coagulation necrosis from direct thermal injury.
Verified Answer: C
Rationale: Compartment syndrome = increased pressure within a closed fascial space
→ venous outflow obstruction → ischemia & necrosis (C). A describes early burn
edema, D describes third-degree burn, B is unrelated.
Q5. A patient with sickle-cell disease in vaso-occlusive crisis has severe pain. The initial
cellular event is:
A. Auto-antibody binding to red-cell membrane
B. Hemoglobin S polymerization under hypoxia → rigid sickled cells → microvascular
occlusion
C. Bone-marrow aplasia from parvovirus B19
D. Iron overload from transfusions
Verified Answer: B
Rationale: Hypoxia → HbS polymerization → rigid sickle-shaped RBCs → microvascular
occlusion & pain (B). A = autoimmune hemolysis, C = aplastic crisis, D = transfusion
siderosis.
