NURS 120 Introduction to Medical-Surgical Nursing: Fluid and
Electrolyte Imbalances 2026 |WCU
1. A patient presents with a serum sodium level of 128 mEq/L. Which clinical
manifestation should the nurse prioritize in the assessment?
A. Confusion, lethargy, and potential for seizures
B. Heightened deep tendon reflexes and tetany
C. Dry mucous membranes and intense thirst
D. Tall, peaked T-waves on the EKG
Answer: A
Rationale: Hyponatremia (sodium < 135 mEq/L) primarily affects the central nervous
system as water shifts into brain cells, leading to cerebral edema, confusion, and seizures.
2. Which intravenous fluid should the nurse anticipate administering for a
patient with severe hypovolemic shock?
A. 0.45% Sodium Chloride (Half-normal saline)
B. 3% Sodium Chloride
C. 5% Dextrose in 0.9% Sodium Chloride (D5NS)
D. 0.9% Sodium Chloride (Normal saline)
Answer: D
Rationale: Isotonic solutions like 0.9% Sodium Chloride or Lactated Ringer’s are used for
rapid volume expansion in patients with hypovolemia.
,3. A nurse is caring for a patient with a potassium level of 6.2 mEq/L. Which
medication is most likely to be ordered for immediate stabilization of the
cardiac membrane?
A. Sodium Polystyrene Sulfonate (Kayexalate)
B. Calcium Gluconate
C. Furosemide (Lasix)
D. Regular Insulin and Dextrose
Answer: B
Rationale: While insulin and Kayexalate lower potassium levels, Calcium Gluconate is
administered first in severe hyperkalemia to antagonize the effects of potassium on the
heart and prevent arrhythmias.
4. The nurse notes a positive Chvostek’s sign in a patient post-thyroidectomy.
Which electrolyte imbalance does this indicate?
A. Hypercalcemia
B. Hypokalemia
C. Hypermagnesemia
D. Hypocalcemia
Answer: D
Rationale: Chvostek’s sign (facial twitching) and Trousseau’s sign are classic indicators of
neuromuscular irritability caused by hypocalcemia, often due to accidental parathyroid
removal.
5. Which patient is at the highest risk for developing respiratory acidosis?
A. A patient with a pulmonary embolism
B. A patient with chronic obstructive pulmonary disease (COPD)
C. A patient experiencing an acute panic attack
D. A patient with excessive nasogastric suctioning
Answer: B
, Rationale: Respiratory acidosis is caused by hypoventilation and CO2 retention, which is
common in chronic conditions like COPD or acute respiratory failure.
6. When assessing a patient with hypokalemia, which EKG finding is
characteristic of this imbalance?
A. Shortened QT interval
B. Widened QRS complex
C. Presence of U-waves
D. Tall, tented T-waves
Answer: C
Rationale: Hypokalemia often presents with flattened T-waves and the appearance of U-
waves. Hyperkalemia presents with peaked T-waves.
7. A patient with syndrome of inappropriate antidiuretic hormone (SIADH) is
most likely to exhibit which lab result?
A. Serum osmolality 265 mOsm/kg
B. Serum sodium 150 mEq/L
C. Urine specific gravity 1.002
D. Hematocrit 55%
Answer: A
Rationale: SIADH causes water retention, leading to dilutional hyponatremia and a
decrease in serum osmolality (normal range 275-295 mOsm/kg).
8. What is the primary risk associated with the rapid correction of chronic
hyponatremia?
A. Cerebral edema
B. Osmotic demyelination syndrome (Central pontine myelinolysis)
C. Acute tubular necrosis
D. Hypovolemic shock
Answer: B
Electrolyte Imbalances 2026 |WCU
1. A patient presents with a serum sodium level of 128 mEq/L. Which clinical
manifestation should the nurse prioritize in the assessment?
A. Confusion, lethargy, and potential for seizures
B. Heightened deep tendon reflexes and tetany
C. Dry mucous membranes and intense thirst
D. Tall, peaked T-waves on the EKG
Answer: A
Rationale: Hyponatremia (sodium < 135 mEq/L) primarily affects the central nervous
system as water shifts into brain cells, leading to cerebral edema, confusion, and seizures.
2. Which intravenous fluid should the nurse anticipate administering for a
patient with severe hypovolemic shock?
A. 0.45% Sodium Chloride (Half-normal saline)
B. 3% Sodium Chloride
C. 5% Dextrose in 0.9% Sodium Chloride (D5NS)
D. 0.9% Sodium Chloride (Normal saline)
Answer: D
Rationale: Isotonic solutions like 0.9% Sodium Chloride or Lactated Ringer’s are used for
rapid volume expansion in patients with hypovolemia.
,3. A nurse is caring for a patient with a potassium level of 6.2 mEq/L. Which
medication is most likely to be ordered for immediate stabilization of the
cardiac membrane?
A. Sodium Polystyrene Sulfonate (Kayexalate)
B. Calcium Gluconate
C. Furosemide (Lasix)
D. Regular Insulin and Dextrose
Answer: B
Rationale: While insulin and Kayexalate lower potassium levels, Calcium Gluconate is
administered first in severe hyperkalemia to antagonize the effects of potassium on the
heart and prevent arrhythmias.
4. The nurse notes a positive Chvostek’s sign in a patient post-thyroidectomy.
Which electrolyte imbalance does this indicate?
A. Hypercalcemia
B. Hypokalemia
C. Hypermagnesemia
D. Hypocalcemia
Answer: D
Rationale: Chvostek’s sign (facial twitching) and Trousseau’s sign are classic indicators of
neuromuscular irritability caused by hypocalcemia, often due to accidental parathyroid
removal.
5. Which patient is at the highest risk for developing respiratory acidosis?
A. A patient with a pulmonary embolism
B. A patient with chronic obstructive pulmonary disease (COPD)
C. A patient experiencing an acute panic attack
D. A patient with excessive nasogastric suctioning
Answer: B
, Rationale: Respiratory acidosis is caused by hypoventilation and CO2 retention, which is
common in chronic conditions like COPD or acute respiratory failure.
6. When assessing a patient with hypokalemia, which EKG finding is
characteristic of this imbalance?
A. Shortened QT interval
B. Widened QRS complex
C. Presence of U-waves
D. Tall, tented T-waves
Answer: C
Rationale: Hypokalemia often presents with flattened T-waves and the appearance of U-
waves. Hyperkalemia presents with peaked T-waves.
7. A patient with syndrome of inappropriate antidiuretic hormone (SIADH) is
most likely to exhibit which lab result?
A. Serum osmolality 265 mOsm/kg
B. Serum sodium 150 mEq/L
C. Urine specific gravity 1.002
D. Hematocrit 55%
Answer: A
Rationale: SIADH causes water retention, leading to dilutional hyponatremia and a
decrease in serum osmolality (normal range 275-295 mOsm/kg).
8. What is the primary risk associated with the rapid correction of chronic
hyponatremia?
A. Cerebral edema
B. Osmotic demyelination syndrome (Central pontine myelinolysis)
C. Acute tubular necrosis
D. Hypovolemic shock
Answer: B
