Electrolyte Disorders Med-Surg
Practice Exam
answers and rationales
1. A patient with hyponatremia is at greatest risk for:
a. Hypertension
b. Seizures
c. Bradycardia
d. Polyuria
b. Seizures
Rationale: Severe hyponatremia can cause cerebral edema, increasing
the risk for seizures and neurological complications.
2. Which electrolyte imbalance is most commonly associated with
chronic kidney disease?
a. Hypokalemia
b. Hyperkalemia
c. Hypocalcemia
d. Hypernatremia
b. Hyperkalemia
Rationale: Impaired renal function reduces potassium excretion, often
leading to hyperkalemia.
3. A patient presents with muscle cramps, tetany, and positive
Chvostek’s sign. The nurse suspects:
a. Hypermagnesemia
b. Hypocalcemia
c. Hyperkalemia
d. Hyponatremia
,b. Hypocalcemia
Rationale: Low calcium levels increase neuromuscular excitability,
causing tetany, cramps, and a positive Chvostek’s sign.
4. Which treatment is priority for severe symptomatic
hyperkalemia?
a. Oral potassium restriction
b. IV calcium gluconate
c. Loop diuretics
d. Sodium bicarbonate
b. IV calcium gluconate
Rationale: IV calcium stabilizes cardiac membranes to prevent life-
threatening arrhythmias in hyperkalemia.
5. Hypomagnesemia can result from all except:
a. Chronic alcoholism
b. Diuretic therapy
c. Malabsorption
d. Renal failure with oliguria
d. Renal failure with oliguria
Rationale: Renal failure often causes hypermagnesemia, not
hypomagnesemia, due to impaired excretion.
6. A patient with hypernatremia is likely to exhibit:
a. Confusion and lethargy
b. Hypotension and bradycardia
c. Muscle twitching and tetany
d. Bradycardia and hyporeflexia
a. Confusion and lethargy
Rationale: Hypernatremia causes cellular dehydration, particularly in
the brain, leading to neurological symptoms.
, 7. Which ECG change is most associated with hypokalemia?
a. Peaked T waves
b. Widened QRS
c. Flattened T waves and U waves
d. ST elevation
c. Flattened T waves and U waves
Rationale: Hypokalemia slows repolarization, causing flattened T
waves and prominent U waves.
8. A patient with hypophosphatemia is at risk for:
a. Osteomalacia and muscle weakness
b. Kidney stones
c. Hyperreflexia
d. Polycythemia
a. Osteomalacia and muscle weakness
Rationale: Low phosphate impairs bone mineralization and ATP
production, leading to muscle weakness and bone softening.
9. Treatment for mild hyponatremia typically includes:
a. Rapid IV hypertonic saline
b. Fluid restriction
c. Loop diuretics
d. IV potassium chloride
b. Fluid restriction
Rationale: In mild hyponatremia, fluid restriction helps correct sodium
without causing rapid shifts that risk osmotic demyelination.
10. Which electrolyte imbalance may occur with prolonged
vomiting?
a. Hyperkalemia
b. Hypokalemia
, c. Hypermagnesemia
d. Hypercalcemia
b. Hypokalemia
Rationale: Vomiting causes loss of gastric acid and potassium, often
leading to hypokalemia.
11. A patient with heart failure is receiving furosemide. The
nurse should monitor for:
a. Hyperkalemia
b. Hypokalemia
c. Hypermagnesemia
d. Hyperphosphatemia
b. Hypokalemia
Rationale: Loop diuretics increase renal potassium excretion,
increasing the risk of hypokalemia.
12. Which condition is most likely to cause hypercalcemia?
a. Chronic diarrhea
b. Hyperparathyroidism
c. Chronic kidney disease
d. Hypoparathyroidism
b. Hyperparathyroidism
Rationale: Excess PTH increases calcium reabsorption from bone,
elevating serum calcium levels.
13. Signs of hypermagnesemia include all except:
a. Hyporeflexia
b. Bradycardia
c. Hypotension
d. Muscle tetany
Practice Exam
answers and rationales
1. A patient with hyponatremia is at greatest risk for:
a. Hypertension
b. Seizures
c. Bradycardia
d. Polyuria
b. Seizures
Rationale: Severe hyponatremia can cause cerebral edema, increasing
the risk for seizures and neurological complications.
2. Which electrolyte imbalance is most commonly associated with
chronic kidney disease?
a. Hypokalemia
b. Hyperkalemia
c. Hypocalcemia
d. Hypernatremia
b. Hyperkalemia
Rationale: Impaired renal function reduces potassium excretion, often
leading to hyperkalemia.
3. A patient presents with muscle cramps, tetany, and positive
Chvostek’s sign. The nurse suspects:
a. Hypermagnesemia
b. Hypocalcemia
c. Hyperkalemia
d. Hyponatremia
,b. Hypocalcemia
Rationale: Low calcium levels increase neuromuscular excitability,
causing tetany, cramps, and a positive Chvostek’s sign.
4. Which treatment is priority for severe symptomatic
hyperkalemia?
a. Oral potassium restriction
b. IV calcium gluconate
c. Loop diuretics
d. Sodium bicarbonate
b. IV calcium gluconate
Rationale: IV calcium stabilizes cardiac membranes to prevent life-
threatening arrhythmias in hyperkalemia.
5. Hypomagnesemia can result from all except:
a. Chronic alcoholism
b. Diuretic therapy
c. Malabsorption
d. Renal failure with oliguria
d. Renal failure with oliguria
Rationale: Renal failure often causes hypermagnesemia, not
hypomagnesemia, due to impaired excretion.
6. A patient with hypernatremia is likely to exhibit:
a. Confusion and lethargy
b. Hypotension and bradycardia
c. Muscle twitching and tetany
d. Bradycardia and hyporeflexia
a. Confusion and lethargy
Rationale: Hypernatremia causes cellular dehydration, particularly in
the brain, leading to neurological symptoms.
, 7. Which ECG change is most associated with hypokalemia?
a. Peaked T waves
b. Widened QRS
c. Flattened T waves and U waves
d. ST elevation
c. Flattened T waves and U waves
Rationale: Hypokalemia slows repolarization, causing flattened T
waves and prominent U waves.
8. A patient with hypophosphatemia is at risk for:
a. Osteomalacia and muscle weakness
b. Kidney stones
c. Hyperreflexia
d. Polycythemia
a. Osteomalacia and muscle weakness
Rationale: Low phosphate impairs bone mineralization and ATP
production, leading to muscle weakness and bone softening.
9. Treatment for mild hyponatremia typically includes:
a. Rapid IV hypertonic saline
b. Fluid restriction
c. Loop diuretics
d. IV potassium chloride
b. Fluid restriction
Rationale: In mild hyponatremia, fluid restriction helps correct sodium
without causing rapid shifts that risk osmotic demyelination.
10. Which electrolyte imbalance may occur with prolonged
vomiting?
a. Hyperkalemia
b. Hypokalemia
, c. Hypermagnesemia
d. Hypercalcemia
b. Hypokalemia
Rationale: Vomiting causes loss of gastric acid and potassium, often
leading to hypokalemia.
11. A patient with heart failure is receiving furosemide. The
nurse should monitor for:
a. Hyperkalemia
b. Hypokalemia
c. Hypermagnesemia
d. Hyperphosphatemia
b. Hypokalemia
Rationale: Loop diuretics increase renal potassium excretion,
increasing the risk of hypokalemia.
12. Which condition is most likely to cause hypercalcemia?
a. Chronic diarrhea
b. Hyperparathyroidism
c. Chronic kidney disease
d. Hypoparathyroidism
b. Hyperparathyroidism
Rationale: Excess PTH increases calcium reabsorption from bone,
elevating serum calcium levels.
13. Signs of hypermagnesemia include all except:
a. Hyporeflexia
b. Bradycardia
c. Hypotension
d. Muscle tetany
