NU 155 MEDICAL-SURGICAL NURSING I
- EXAM 3 PREP QUESTIONS AND
ANSWERS
1. A patient with a serum potassium level of 6.2 mEq/L is admitted. Which ECG change is
most characteristic of this electrolyte imbalance?
A. Prominent U waves
B. ST-segment depression
C. Tall, peaked T waves
D. Shortened QT interval
Answer: C
Conceptual Explanation: Hyperkalemia (potassium > 5.0 mEq/L) typically manifests on
an ECG as tall, peaked T waves, widened QRS complexes, and prolonged PR intervals.
2. Which clinical manifestation should the nurse prioritize when assessing a patient for
hypocalcemia?
A. Decreased deep tendon reflexes
B. Positive Chvostek’s sign
C. Polyuria and polydipsia
,D. Constipation and muscle weakness
Answer: B
Conceptual Explanation: Hypocalcemia increases neuromuscular excitability. A positive
Chvostek’s sign (facial twitching when the facial nerve is tapped) is a classic indicator.
3. A patient is diagnosed with respiratory acidosis. Which arterial blood gas (ABG) result is
consistent with this diagnosis?
A. pH 7.50, PaCO2 40, HCO3 32
B. pH 7.48, PaCO2 30, HCO3 22
C. pH 7.30, PaCO2 35, HCO3 18
D. pH 7.32, PaCO2 50, HCO3 24
Answer: D
Conceptual Explanation: Respiratory acidosis is characterized by a low pH (<7.35) and an
elevated PaCO2 (>45 mmHg).
4. A nurse is caring for a patient with a chest tube. The nurse notes continuous bubbling in
the water-seal chamber. What is the most appropriate action?
A. Document this as a normal finding for a patient with a pneumothorax.
B. Clamp the chest tube immediately to prevent tension pneumothorax.
C. Increase the suction to the prescribed level.
D. Check the system for an air leak starting from the patient’s dressing.
, Answer: D
Conceptual Explanation: Continuous bubbling in the water-seal chamber indicates an air
leak in the system, which must be located and addressed. Intermittent bubbling is normal
during expiration in patients with pneumothorax.
5. What is the priority nursing intervention for a patient experiencing a pulmonary embolism?
A. Initiating IV fluids at a rapid rate
B. Applying sequential compression devices (SCDs)
C. Administering oxygen via nasal cannula
D. Teaching the patient deep breathing exercises
Answer: C
Conceptual Explanation: The priority in pulmonary embolism is maintaining oxygenation
and gas exchange. Oxygen therapy should be started immediately.
6. A patient has a sodium level of 120 mEq/L. Which safety precaution is most important for
the nurse to implement?
A. Cardiac monitoring
B. Seizure precautions
C. High-protein diet
D. Increased fluid intake
Answer: B
- EXAM 3 PREP QUESTIONS AND
ANSWERS
1. A patient with a serum potassium level of 6.2 mEq/L is admitted. Which ECG change is
most characteristic of this electrolyte imbalance?
A. Prominent U waves
B. ST-segment depression
C. Tall, peaked T waves
D. Shortened QT interval
Answer: C
Conceptual Explanation: Hyperkalemia (potassium > 5.0 mEq/L) typically manifests on
an ECG as tall, peaked T waves, widened QRS complexes, and prolonged PR intervals.
2. Which clinical manifestation should the nurse prioritize when assessing a patient for
hypocalcemia?
A. Decreased deep tendon reflexes
B. Positive Chvostek’s sign
C. Polyuria and polydipsia
,D. Constipation and muscle weakness
Answer: B
Conceptual Explanation: Hypocalcemia increases neuromuscular excitability. A positive
Chvostek’s sign (facial twitching when the facial nerve is tapped) is a classic indicator.
3. A patient is diagnosed with respiratory acidosis. Which arterial blood gas (ABG) result is
consistent with this diagnosis?
A. pH 7.50, PaCO2 40, HCO3 32
B. pH 7.48, PaCO2 30, HCO3 22
C. pH 7.30, PaCO2 35, HCO3 18
D. pH 7.32, PaCO2 50, HCO3 24
Answer: D
Conceptual Explanation: Respiratory acidosis is characterized by a low pH (<7.35) and an
elevated PaCO2 (>45 mmHg).
4. A nurse is caring for a patient with a chest tube. The nurse notes continuous bubbling in
the water-seal chamber. What is the most appropriate action?
A. Document this as a normal finding for a patient with a pneumothorax.
B. Clamp the chest tube immediately to prevent tension pneumothorax.
C. Increase the suction to the prescribed level.
D. Check the system for an air leak starting from the patient’s dressing.
, Answer: D
Conceptual Explanation: Continuous bubbling in the water-seal chamber indicates an air
leak in the system, which must be located and addressed. Intermittent bubbling is normal
during expiration in patients with pneumothorax.
5. What is the priority nursing intervention for a patient experiencing a pulmonary embolism?
A. Initiating IV fluids at a rapid rate
B. Applying sequential compression devices (SCDs)
C. Administering oxygen via nasal cannula
D. Teaching the patient deep breathing exercises
Answer: C
Conceptual Explanation: The priority in pulmonary embolism is maintaining oxygenation
and gas exchange. Oxygen therapy should be started immediately.
6. A patient has a sodium level of 120 mEq/L. Which safety precaution is most important for
the nurse to implement?
A. Cardiac monitoring
B. Seizure precautions
C. High-protein diet
D. Increased fluid intake
Answer: B
