NCLEX RN Exam Bank: Fluid Electrolyte &
Acid–Base Disorders, Interpretation &
Treatment
Table of Contents
Subtopic 1: Sodium Imbalances, Hyponatremia & Hypernatremia: Recognition and
Management ................................................................................................................ 2
Subtopic 2: Potassium Imbalances—Hypokalemia & Hyperkalemia: ECG and Cardiac Risks
.................................................................................................................................... 9
Subtopic 3: Calcium and Magnesium Imbalances—Neuromuscular and Cardiac Impact. 17
Subtopic 4: Acid–Base Interpretation—ABG Analysis and Imbalance Patterns ................. 25
Subtopic 5: Fluid Volume Imbalances – Dehydration, Hypovolemia & Overload ............... 32
Subtopic 6: Electrolyte Replacement Therapies and IV Compatibility .............................. 40
Subtopic 7: Mixed Acid–Base Disorders & Compensation Mechanisms ........................... 48
Subtopic 8: Fluid Volume Overload and Deficit—Recognition & Management.................. 55
Subtopic 9: Fluid Imbalance in Renal and Hepatic Failure (Q161–Q180) .......................... 62
Subtopic 10: Integrated Clinical Decision-Making for Fluid and Electrolyte Imbalances.... 70
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Subtopic 1: Sodium Imbalances, Hyponatremia &
Hypernatremia: Recognition and Management
Question 1:
A patient is admitted with a serum sodium level of 122 mEq/L. Which symptom is the nurse
most likely to observe?
A. Hypotension
B. Muscle rigidity
C. Confusion and lethargy
D. Warm, flushed skin
Correct answer: C
Rationale: Hyponatremia causes cerebral edema, leading to neurologic symptoms like
confusion, lethargy, and possible seizures.
Question 2:
Which intervention is most appropriate for a patient with SIADH-induced hyponatremia?
A. Administer 0.9% normal saline rapidly
B. Encourage oral water intake
C. Fluid restriction and monitor neurological status
D. Give potassium supplements
Correct answer: C
Rationale: SIADH causes water retention and dilutional hyponatremia. Fluid restriction is
key to correcting sodium levels and preventing cerebral edema.
Question 3:
Which of the following foods should be avoided by a patient with chronic hypernatremia?
A. Canned soups and processed meats
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B. Bananas and oranges
C. White rice and plain yogurt
D. Fresh chicken and green beans
Correct answer: A
Rationale: Processed foods like canned soups contain high sodium content, which can
exacerbate hypernatremia.
Question 4:
What is the most critical nursing intervention for a patient with sodium level of 159 mEq/L?
A. Administer salt tablets
B. Offer fluids rich in electrolytes
C. Administer hypotonic IV fluids slowly
D. Initiate seizure precautions
Correct answer: C
Rationale: Hypernatremia requires gradual correction with hypotonic fluids to prevent
cerebral edema from rapid fluid shifts.
Question 5:
Which of the following patients is most at risk for developing hyponatremia?
A. A patient on a low-sodium diet taking hydrochlorothiazide
B. A patient receiving total parenteral nutrition
C. A patient with diabetes mellitus
D. A patient using corticosteroids
Correct answer: A
Rationale: Thiazide diuretics and sodium restriction increase risk for hyponatremia by
promoting sodium loss.
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Question 6:
What is a typical ECG change seen in severe hypernatremia?
A. Prolonged QT interval
B. Peaked T waves
C. None—ECG is usually normal
D. Flattened P waves
Correct answer: C
Rationale: Sodium primarily affects CNS rather than cardiac conduction; ECG changes are
typically absent.
Question 7:
Which serum sodium level indicates critical hyponatremia requiring ICU care?
A. 135 mEq/L
B. 130 mEq/L
C. 118 mEq/L
D. 140 mEq/L
Correct answer: C
Rationale: A sodium level <120 mEq/L is life-threatening and requires ICU-level monitoring
and treatment.
Question 8:
A nurse is caring for a patient with severe hyponatremia. Which of the following orders
would require clarification?
A. Seizure precautions
B. Fluid restriction
C. Monitor serum sodium
D. Administer 3% saline at 250 mL/hr