CCRN Test Bank - Latest Update 2026
Comprehensive Examination with Questions]
Question 1
A 20-mm S wave in lead V1 and a 25-mm R wave in lead V6 are noted on a patient's 12-lead
electrocardiogram. This would indicate which of the following?
A. Right bundle branch block (RBBB)
B. Left ventricular hypertrophy
C. Posterior wall myocardial infarction (MI)
D. Right ventricular hypertrophy
Correct ANSWER: B. Left ventricular hypertrophy
Rationale:
A. Right bundle branch block (RBBB) - Incorrect. RBBB is characterized by a widened QRS complex
(>120ms) with RSR' pattern in V1-V2 and wide S waves in V5-V6. The criteria described do not match
RBBB patterns.
B. Left ventricular hypertrophy - CORRECT. When the depth of the S wave in lead V1 or V2 plus the
height of the R wave in lead V5 or V6 is 35 mm or greater, this constitutes voltage criteria for left
ventricular hypertrophy. The calculation (S wave in V1 + R wave in V6 = 20mm + 25mm = 45mm)
exceeds the 35mm threshold.
C. Posterior wall myocardial infarction (MI) - Incorrect. Posterior wall MI typically shows tall R waves in
V1-V2 (reflecting reciprocal changes) with ST depression, not the specific voltage criteria described.
,D. Right ventricular hypertrophy - Incorrect. RVH typically shows right axis deviation, tall R waves in V1-
V2, and deep S waves in V5-V6, which is opposite of the findings described.
Question 2
A 22-year-old man is admitted after a bicycle collision with a tree. He has a contusion on the right side of
his head. An intraventricular catheter has been inserted via a burr hole to monitor his intracranial
pressure (ICP). He develops respiratory depression and is intubated and mechanically ventilated. Which
of the following is the most likely cause of an increase in ICP at this time?
A. Positive pressure ventilation
B. Hypocapnia caused by hyperventilation
C. Sedation
D. Cerebral dehydration caused by osmotic diuretics
Correct ANSWER: A. Positive pressure ventilation
Rationale:
A. Positive pressure ventilation - CORRECT. Positive pressure ventilation increases intrathoracic
pressure, which impedes venous return from the brain, leading to increased intracranial pressure. This is
a well-documented complication of mechanical ventilation in patients with head injuries.
B. Hypocapnia caused by hyperventilation - Incorrect. Hypocapnia causes cerebral vasoconstriction,
which actually decreases cerebral blood volume and ICP. This is why hyperventilation was historically
used as a treatment for elevated ICP.
C. Sedation - Incorrect. Sedation generally decreases ICP by reducing metabolic demand, lowering
cerebral blood flow, and decreasing agitation that can increase ICP.
D. Cerebral dehydration caused by osmotic diuretics - Incorrect. Osmotic diuretics such as mannitol
actually reduce cerebral edema and decrease ICP by drawing fluid from brain tissue into the vascular
space.
,Question 3
A 22-year-old man is admitted to the critical care unit after a motor vehicle collision. The emergency
department nurse reports that he was unconscious at the scene of the accident, but he is now alert and
oriented. Skull films show a linear fracture of the right temporal bone. He is at significant risk for:
A. Epidural hematoma
B. Subdural hematoma
C. Subarachnoid hemorrhage
D. Intracerebral hemorrhage
Correct ANSWER: A. Epidural hematoma
Rationale:
A. Epidural hematoma - CORRECT. A lucid interval following loss of consciousness with a temporal bone
fracture is classic presentation of an epidural hematoma. Temporal bone fractures can lacerate the
middle meningeal artery, causing rapid arterial bleeding into the epidural space. The patient may
initially be lucid followed by rapid deterioration as the hematoma expands.
B. Subdural hematoma - Incorrect. Subdural hematomas typically occur with venous bleeding, have a
slower onset, and are more common in elderly patients or those on anticoagulants. The lucid interval is
less characteristic.
C. Subarachnoid hemorrhage - Incorrect. Subarachnoid hemorrhage typically presents with sudden
severe headache ("thunderclap") and is more commonly associated with ruptured aneurysms, not
temporal bone fractures.
D. Intracerebral hemorrhage - Incorrect. Intracerebral hemorrhage is more commonly associated with
hypertension, anticoagulation, or penetrating injuries rather than blunt trauma with a lucid interval.
Question 4
, A patient with acute respiratory distress syndrome (ARDS) is receiving mechanical ventilation with the
following settings: tidal volume 6 mL/kg predicted body weight, PEEP 12 cm H2O, FiO2 0.8. The arterial
blood gas shows pH 7.28, PaCO2 52 mmHg, PaO2 68 mmHg, HCO3 24 mEq/L. Which of the following
interventions is most appropriate?
A. Increase tidal volume to 8 mL/kg
B. Decrease PEEP to 8 cm H2O
C. Increase respiratory rate
D. Increase FiO2 to 1.0
Correct ANSWER: C. Increase respiratory rate
Rationale:
A. Increase tidal volume to 8 mL/kg - Incorrect. In ARDS, lung-protective ventilation recommends tidal
volumes of 4-6 mL/kg predicted body weight to prevent volutrauma and barotrauma. Increasing tidal
volume would increase the risk of lung injury.
B. Decrease PEEP to 8 cm H2O - Incorrect. The patient's PaO2 is only 68 mmHg despite FiO2 of 0.8 and
PEEP of 12 cm H2O, suggesting significant oxygenation impairment. Decreasing PEEP would likely
worsen oxygenation.
C. Increase respiratory rate - CORRECT. The patient is hypercapnic with respiratory acidosis (pH 7.28,
PaCO2 52). With lung-protective ventilation limiting tidal volume, the appropriate intervention to
improve minute ventilation and reduce PaCO2 is to increase the respiratory rate (within limits to avoid
auto-PEEP).
D. Increase FiO2 to 1.0 - Incorrect. While this would increase oxygenation, it does not address the
hypercapnia and respiratory acidosis. The priority is to correct the acidemia, and limiting oxygen toxicity
risk is important.
Question 5
Comprehensive Examination with Questions]
Question 1
A 20-mm S wave in lead V1 and a 25-mm R wave in lead V6 are noted on a patient's 12-lead
electrocardiogram. This would indicate which of the following?
A. Right bundle branch block (RBBB)
B. Left ventricular hypertrophy
C. Posterior wall myocardial infarction (MI)
D. Right ventricular hypertrophy
Correct ANSWER: B. Left ventricular hypertrophy
Rationale:
A. Right bundle branch block (RBBB) - Incorrect. RBBB is characterized by a widened QRS complex
(>120ms) with RSR' pattern in V1-V2 and wide S waves in V5-V6. The criteria described do not match
RBBB patterns.
B. Left ventricular hypertrophy - CORRECT. When the depth of the S wave in lead V1 or V2 plus the
height of the R wave in lead V5 or V6 is 35 mm or greater, this constitutes voltage criteria for left
ventricular hypertrophy. The calculation (S wave in V1 + R wave in V6 = 20mm + 25mm = 45mm)
exceeds the 35mm threshold.
C. Posterior wall myocardial infarction (MI) - Incorrect. Posterior wall MI typically shows tall R waves in
V1-V2 (reflecting reciprocal changes) with ST depression, not the specific voltage criteria described.
,D. Right ventricular hypertrophy - Incorrect. RVH typically shows right axis deviation, tall R waves in V1-
V2, and deep S waves in V5-V6, which is opposite of the findings described.
Question 2
A 22-year-old man is admitted after a bicycle collision with a tree. He has a contusion on the right side of
his head. An intraventricular catheter has been inserted via a burr hole to monitor his intracranial
pressure (ICP). He develops respiratory depression and is intubated and mechanically ventilated. Which
of the following is the most likely cause of an increase in ICP at this time?
A. Positive pressure ventilation
B. Hypocapnia caused by hyperventilation
C. Sedation
D. Cerebral dehydration caused by osmotic diuretics
Correct ANSWER: A. Positive pressure ventilation
Rationale:
A. Positive pressure ventilation - CORRECT. Positive pressure ventilation increases intrathoracic
pressure, which impedes venous return from the brain, leading to increased intracranial pressure. This is
a well-documented complication of mechanical ventilation in patients with head injuries.
B. Hypocapnia caused by hyperventilation - Incorrect. Hypocapnia causes cerebral vasoconstriction,
which actually decreases cerebral blood volume and ICP. This is why hyperventilation was historically
used as a treatment for elevated ICP.
C. Sedation - Incorrect. Sedation generally decreases ICP by reducing metabolic demand, lowering
cerebral blood flow, and decreasing agitation that can increase ICP.
D. Cerebral dehydration caused by osmotic diuretics - Incorrect. Osmotic diuretics such as mannitol
actually reduce cerebral edema and decrease ICP by drawing fluid from brain tissue into the vascular
space.
,Question 3
A 22-year-old man is admitted to the critical care unit after a motor vehicle collision. The emergency
department nurse reports that he was unconscious at the scene of the accident, but he is now alert and
oriented. Skull films show a linear fracture of the right temporal bone. He is at significant risk for:
A. Epidural hematoma
B. Subdural hematoma
C. Subarachnoid hemorrhage
D. Intracerebral hemorrhage
Correct ANSWER: A. Epidural hematoma
Rationale:
A. Epidural hematoma - CORRECT. A lucid interval following loss of consciousness with a temporal bone
fracture is classic presentation of an epidural hematoma. Temporal bone fractures can lacerate the
middle meningeal artery, causing rapid arterial bleeding into the epidural space. The patient may
initially be lucid followed by rapid deterioration as the hematoma expands.
B. Subdural hematoma - Incorrect. Subdural hematomas typically occur with venous bleeding, have a
slower onset, and are more common in elderly patients or those on anticoagulants. The lucid interval is
less characteristic.
C. Subarachnoid hemorrhage - Incorrect. Subarachnoid hemorrhage typically presents with sudden
severe headache ("thunderclap") and is more commonly associated with ruptured aneurysms, not
temporal bone fractures.
D. Intracerebral hemorrhage - Incorrect. Intracerebral hemorrhage is more commonly associated with
hypertension, anticoagulation, or penetrating injuries rather than blunt trauma with a lucid interval.
Question 4
, A patient with acute respiratory distress syndrome (ARDS) is receiving mechanical ventilation with the
following settings: tidal volume 6 mL/kg predicted body weight, PEEP 12 cm H2O, FiO2 0.8. The arterial
blood gas shows pH 7.28, PaCO2 52 mmHg, PaO2 68 mmHg, HCO3 24 mEq/L. Which of the following
interventions is most appropriate?
A. Increase tidal volume to 8 mL/kg
B. Decrease PEEP to 8 cm H2O
C. Increase respiratory rate
D. Increase FiO2 to 1.0
Correct ANSWER: C. Increase respiratory rate
Rationale:
A. Increase tidal volume to 8 mL/kg - Incorrect. In ARDS, lung-protective ventilation recommends tidal
volumes of 4-6 mL/kg predicted body weight to prevent volutrauma and barotrauma. Increasing tidal
volume would increase the risk of lung injury.
B. Decrease PEEP to 8 cm H2O - Incorrect. The patient's PaO2 is only 68 mmHg despite FiO2 of 0.8 and
PEEP of 12 cm H2O, suggesting significant oxygenation impairment. Decreasing PEEP would likely
worsen oxygenation.
C. Increase respiratory rate - CORRECT. The patient is hypercapnic with respiratory acidosis (pH 7.28,
PaCO2 52). With lung-protective ventilation limiting tidal volume, the appropriate intervention to
improve minute ventilation and reduce PaCO2 is to increase the respiratory rate (within limits to avoid
auto-PEEP).
D. Increase FiO2 to 1.0 - Incorrect. While this would increase oxygenation, it does not address the
hypercapnia and respiratory acidosis. The priority is to correct the acidemia, and limiting oxygen toxicity
risk is important.
Question 5
