Fluid and Electrolyte Imbalances - NURS 120 (2026 Update) WCU
1. A patient with a serum potassium level of 6.2 mEq/L is admitted. Which EKG
finding is the nurse most likely to observe?
A. Tall, peaked T waves
B. Prolonged PR interval
C. Prominent U waves
D. ST-segment depression
Answer: A
Rationale: Hyperkalemia (K+ > 5.0 mEq/L) typically manifests on an EKG as tall, peaked T
waves, widened QRS complexes, and potentially lost P waves as levels rise.
2. Which intravenous solution is considered isotonic and is the only fluid used
when administering blood products?
A. 0.45% Sodium Chloride
B. 0.9% Sodium Chloride
C. Dextrose 5% in Water
D. Lactated Ringer’s
Answer: B
Rationale: 0.9% Sodium Chloride (Normal Saline) is an isotonic crystalloid and is the only
solution compatible with blood products; other fluids can cause hemolysis.
,3. A client presents with a serum sodium of 128 mEq/L. Which clinical
manifestation should the nurse prioritize for assessment?
A. Increased thirst and dry mucous membranes
B. Hyperreflexia and muscle twitching
C. Altered mental status and seizure activity
D. Orthostatic hypotension and tachycardia
Answer: C
Rationale: Hyponatremia leads to water shifting into brain cells, causing cerebral edema.
Assessment for neurological changes, including confusion and seizures, is the priority.
4. The nurse is caring for a patient with hypocalcemia. Which physical
assessment finding is consistent with this diagnosis?
A. Positive Trousseau’s sign
B. Diminished deep tendon reflexes
C. Constipation and abdominal distension
D. Polyuria and bone pain
Answer: A
Rationale: Hypocalcemia increases neuromuscular excitability, leading to tetany, which is
evidenced by Chvostek’s sign (facial twitching) and Trousseau’s sign (carpal spasm with BP
cuff inflation).
5. A patient has been taking furosemide for congestive heart failure. Which
electrolyte imbalance is this patient at highest risk for?
A. Hyperkalemia
B. Hypermagnesemia
C. Hypercalcemia
D. Hypokalemia
Answer: D
, Rationale: Furosemide is a loop diuretic that promotes the excretion of water, sodium, and
potassium, frequently leading to hypokalemia.
6. Which hormone is primarily responsible for the renal reabsorption of water,
effectively concentrating urine?
A. Atrial Natriuretic Peptide (ANP)
B. Antidiuretic Hormone (ADH)
C. Aldosterone
D. Parathyroid Hormone (PTH)
Answer: B
Rationale: ADH (Vasopressin) acts on the distal tubules and collecting ducts of the kidney
to reabsorb water back into the blood, regulated by the posterior pituitary.
7. A patient with chronic kidney disease (CKD) has a serum phosphorus of 5.8
mg/dL. The nurse should also monitor for which related imbalance?
A. Hypocalcemia
B. Hypercalcemia
C. Hypokalemia
D. Hypernatremia
Answer: A
Rationale: Phosphorus and calcium have an inverse relationship. When phosphorus levels
are high, calcium levels typically drop due to precipitation and decreased Vitamin D
activation.
1. A patient with a serum potassium level of 6.2 mEq/L is admitted. Which EKG
finding is the nurse most likely to observe?
A. Tall, peaked T waves
B. Prolonged PR interval
C. Prominent U waves
D. ST-segment depression
Answer: A
Rationale: Hyperkalemia (K+ > 5.0 mEq/L) typically manifests on an EKG as tall, peaked T
waves, widened QRS complexes, and potentially lost P waves as levels rise.
2. Which intravenous solution is considered isotonic and is the only fluid used
when administering blood products?
A. 0.45% Sodium Chloride
B. 0.9% Sodium Chloride
C. Dextrose 5% in Water
D. Lactated Ringer’s
Answer: B
Rationale: 0.9% Sodium Chloride (Normal Saline) is an isotonic crystalloid and is the only
solution compatible with blood products; other fluids can cause hemolysis.
,3. A client presents with a serum sodium of 128 mEq/L. Which clinical
manifestation should the nurse prioritize for assessment?
A. Increased thirst and dry mucous membranes
B. Hyperreflexia and muscle twitching
C. Altered mental status and seizure activity
D. Orthostatic hypotension and tachycardia
Answer: C
Rationale: Hyponatremia leads to water shifting into brain cells, causing cerebral edema.
Assessment for neurological changes, including confusion and seizures, is the priority.
4. The nurse is caring for a patient with hypocalcemia. Which physical
assessment finding is consistent with this diagnosis?
A. Positive Trousseau’s sign
B. Diminished deep tendon reflexes
C. Constipation and abdominal distension
D. Polyuria and bone pain
Answer: A
Rationale: Hypocalcemia increases neuromuscular excitability, leading to tetany, which is
evidenced by Chvostek’s sign (facial twitching) and Trousseau’s sign (carpal spasm with BP
cuff inflation).
5. A patient has been taking furosemide for congestive heart failure. Which
electrolyte imbalance is this patient at highest risk for?
A. Hyperkalemia
B. Hypermagnesemia
C. Hypercalcemia
D. Hypokalemia
Answer: D
, Rationale: Furosemide is a loop diuretic that promotes the excretion of water, sodium, and
potassium, frequently leading to hypokalemia.
6. Which hormone is primarily responsible for the renal reabsorption of water,
effectively concentrating urine?
A. Atrial Natriuretic Peptide (ANP)
B. Antidiuretic Hormone (ADH)
C. Aldosterone
D. Parathyroid Hormone (PTH)
Answer: B
Rationale: ADH (Vasopressin) acts on the distal tubules and collecting ducts of the kidney
to reabsorb water back into the blood, regulated by the posterior pituitary.
7. A patient with chronic kidney disease (CKD) has a serum phosphorus of 5.8
mg/dL. The nurse should also monitor for which related imbalance?
A. Hypocalcemia
B. Hypercalcemia
C. Hypokalemia
D. Hypernatremia
Answer: A
Rationale: Phosphorus and calcium have an inverse relationship. When phosphorus levels
are high, calcium levels typically drop due to precipitation and decreased Vitamin D
activation.
