BSN 266 HESI Med-Surg Nursing Exam 1 – Practice Q&A
(Original Practice Questions – Not Actual HESI Items)
Instructions:
One best answer per question.
Correct answer: bold.
Rationale: italics.
Fluids, Electrolytes & Acid–Base (1–20)
1. A patient has serum sodium 128 mEq/L, confusion, and lethargy. Which condition is most likely?
A. Hypernatremia
B. Hyponatremia
C. Hyperkalemia
D. Hypocalcemia
Answer: B
Rationale: Low sodium with neuro symptoms indicates hyponatremia.
2. Which intervention is priority for severe symptomatic hyponatremia?
A. Fluid restriction only
B. Hypertonic (3%) saline with close monitoring
C. Rapid correction with large volumes of D5W
D. Potassium supplementation
Answer: B
Rationale: Hypertonic saline is used for severe symptomatic hyponatremia to prevent seizures/coma.
3. A patient with vomiting and nasogastric suction is at highest risk for:
A. Metabolic acidosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Respiratory alkalosis
Answer: B
Rationale: Loss of gastric acid (HCl) leads to metabolic alkalosis.
4. ABG: pH 7.25, PaCO₂ 50, HCO₃⁻ 24. Interpretation:
A. Uncompensated respiratory acidosis
B. Uncompensated metabolic acidosis
C. Compensated respiratory alkalosis
D. Compensated metabolic alkalosis
Answer: A
Rationale: Low pH with high PaCO₂ and normal HCO₃⁻ indicates primary respiratory acidosis.
, 5. A patient with DKA is most likely to have which acid–base imbalance?
A. Metabolic alkalosis
B. Metabolic acidosis
C. Respiratory acidosis
D. Respiratory alkalosis
Answer: B
Rationale: Ketone accumulation causes high anion gap metabolic acidosis.
6. Which finding suggests hypokalemia?
A. Hyperactive reflexes
B. Muscle weakness, cramps, and arrhythmias
C. Diarrhea
D. Oliguria
Answer: B
Rationale: Low potassium causes neuromuscular weakness and cardiac dysrhythmias.
7. A patient on furosemide is at highest risk for:
A. Hyperkalemia
B. Hypokalemia
C. Hypercalcemia
D. Hyperphosphatemia
Answer: B
Rationale: Loop diuretics increase potassium excretion.
8. Which ECG change is associated with hyperkalemia?
A. U waves
B. Peaked T waves
C. ST depression
D. Prolonged QT
Answer: B
Rationale: Hyperkalemia classically causes peaked T waves, then widened QRS.
9. A patient with chronic kidney disease is most at risk for:
A. Hypokalemia
B. Hyperkalemia
C. Hypophosphatemia
D. Hypercalcemia
Answer: B
Rationale: Impaired renal excretion leads to potassium retention.
10. Which IV fluid is isotonic and commonly used for volume expansion?
A. D5W
B. 0.45% NaCl
C. 0.9% NaCl
D. 3% NaCl
, Answer: C
Rationale: 0.9% NaCl is isotonic and used for intravascular volume expansion.
11. A patient with fluid volume overload may present with:
A. Dry mucous membranes
B. Crackles, edema, and weight gain
C. Tachycardia and hypotension
D. Flat neck veins
Answer: B
Rationale: Overload causes pulmonary congestion, edema, and weight gain.
12. Priority nursing action for a patient with suspected fluid overload:
A. Increase IV fluids
B. Elevate head of bed, assess lungs, and notify provider
C. Encourage high sodium intake
D. Restrict all oral intake permanently
Answer: B
Rationale: Elevating HOB and assessing respiratory status are immediate priorities.
13. Which lab value is most important to monitor in a patient receiving IV potassium?
A. Sodium
B. Potassium
C. Calcium
D. Magnesium
Answer: B
Rationale: IV potassium requires close monitoring to prevent dangerous hyperkalemia.
14. Safe administration of IV potassium includes:
A. IV push over 1 minute
B. Diluted and infused no faster than 10 mEq/hr via peripheral line (per policy)
C. Mixing in a small volume bag and running wide open
D. Giving as a bolus
Answer: B
Rationale: Potassium must never be given IV push; rate limits prevent cardiac arrest.
15. A patient with metabolic acidosis will typically exhibit which respiratory compensation?
A. Hypoventilation
B. Kussmaul respirations (deep, rapid breathing)
C. Normal respirations
D. Apnea
Answer: B
Rationale: The body compensates by blowing off CO₂ via deep, rapid breaths.
16. Which condition is a common cause of respiratory acidosis?
A. Hyperventilation due to anxiety
B. COPD exacerbation with hypoventilation
(Original Practice Questions – Not Actual HESI Items)
Instructions:
One best answer per question.
Correct answer: bold.
Rationale: italics.
Fluids, Electrolytes & Acid–Base (1–20)
1. A patient has serum sodium 128 mEq/L, confusion, and lethargy. Which condition is most likely?
A. Hypernatremia
B. Hyponatremia
C. Hyperkalemia
D. Hypocalcemia
Answer: B
Rationale: Low sodium with neuro symptoms indicates hyponatremia.
2. Which intervention is priority for severe symptomatic hyponatremia?
A. Fluid restriction only
B. Hypertonic (3%) saline with close monitoring
C. Rapid correction with large volumes of D5W
D. Potassium supplementation
Answer: B
Rationale: Hypertonic saline is used for severe symptomatic hyponatremia to prevent seizures/coma.
3. A patient with vomiting and nasogastric suction is at highest risk for:
A. Metabolic acidosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Respiratory alkalosis
Answer: B
Rationale: Loss of gastric acid (HCl) leads to metabolic alkalosis.
4. ABG: pH 7.25, PaCO₂ 50, HCO₃⁻ 24. Interpretation:
A. Uncompensated respiratory acidosis
B. Uncompensated metabolic acidosis
C. Compensated respiratory alkalosis
D. Compensated metabolic alkalosis
Answer: A
Rationale: Low pH with high PaCO₂ and normal HCO₃⁻ indicates primary respiratory acidosis.
, 5. A patient with DKA is most likely to have which acid–base imbalance?
A. Metabolic alkalosis
B. Metabolic acidosis
C. Respiratory acidosis
D. Respiratory alkalosis
Answer: B
Rationale: Ketone accumulation causes high anion gap metabolic acidosis.
6. Which finding suggests hypokalemia?
A. Hyperactive reflexes
B. Muscle weakness, cramps, and arrhythmias
C. Diarrhea
D. Oliguria
Answer: B
Rationale: Low potassium causes neuromuscular weakness and cardiac dysrhythmias.
7. A patient on furosemide is at highest risk for:
A. Hyperkalemia
B. Hypokalemia
C. Hypercalcemia
D. Hyperphosphatemia
Answer: B
Rationale: Loop diuretics increase potassium excretion.
8. Which ECG change is associated with hyperkalemia?
A. U waves
B. Peaked T waves
C. ST depression
D. Prolonged QT
Answer: B
Rationale: Hyperkalemia classically causes peaked T waves, then widened QRS.
9. A patient with chronic kidney disease is most at risk for:
A. Hypokalemia
B. Hyperkalemia
C. Hypophosphatemia
D. Hypercalcemia
Answer: B
Rationale: Impaired renal excretion leads to potassium retention.
10. Which IV fluid is isotonic and commonly used for volume expansion?
A. D5W
B. 0.45% NaCl
C. 0.9% NaCl
D. 3% NaCl
, Answer: C
Rationale: 0.9% NaCl is isotonic and used for intravascular volume expansion.
11. A patient with fluid volume overload may present with:
A. Dry mucous membranes
B. Crackles, edema, and weight gain
C. Tachycardia and hypotension
D. Flat neck veins
Answer: B
Rationale: Overload causes pulmonary congestion, edema, and weight gain.
12. Priority nursing action for a patient with suspected fluid overload:
A. Increase IV fluids
B. Elevate head of bed, assess lungs, and notify provider
C. Encourage high sodium intake
D. Restrict all oral intake permanently
Answer: B
Rationale: Elevating HOB and assessing respiratory status are immediate priorities.
13. Which lab value is most important to monitor in a patient receiving IV potassium?
A. Sodium
B. Potassium
C. Calcium
D. Magnesium
Answer: B
Rationale: IV potassium requires close monitoring to prevent dangerous hyperkalemia.
14. Safe administration of IV potassium includes:
A. IV push over 1 minute
B. Diluted and infused no faster than 10 mEq/hr via peripheral line (per policy)
C. Mixing in a small volume bag and running wide open
D. Giving as a bolus
Answer: B
Rationale: Potassium must never be given IV push; rate limits prevent cardiac arrest.
15. A patient with metabolic acidosis will typically exhibit which respiratory compensation?
A. Hypoventilation
B. Kussmaul respirations (deep, rapid breathing)
C. Normal respirations
D. Apnea
Answer: B
Rationale: The body compensates by blowing off CO₂ via deep, rapid breaths.
16. Which condition is a common cause of respiratory acidosis?
A. Hyperventilation due to anxiety
B. COPD exacerbation with hypoventilation
