ATI CBC LEVEL 2 PRACTICE EXAM – BATCH 1 (Questions 1-25)
🔹 CONCEPT: FLUID & ELECTROLYTE BALANCE
Question 1
A nurse is assessing a client with a serum sodium level of 128 mEq/L. Which finding should the nurse
expect?
A) Hyperreflexia
B) Confusion and headache
C) Dry, sticky mucous membranes
D) Increased urine specific gravity
✅ Answer: B
💡 Rationale: Hyponatremia (Na⁺ <135 mEq/L) causes water to shift into cells, leading to cerebral
edema. Neurological manifestations like confusion, headache, lethargy, and seizures are priority
findings. Hyperreflexia (A) is associated with hypernatremia or hypocalcemia. Dry mucous membranes
(C) and increased urine specific gravity (D) indicate dehydration/hypernatremia, not hyponatremia.
Question 2
A client receiving IV furosemide for heart failure has a potassium level of 3.1 mEq/L. Which
assessment finding is the nurse's priority?
A) Muscle weakness
B) Cardiac dysrhythmias
C) Nausea and vomiting
D) Fatigue
✅ Answer: B
💡 Rationale: Hypokalemia (K⁺ <3.5 mEq/L) increases risk for life-threatening cardiac dysrhythmias due
to altered myocardial cell membrane potential. While muscle weakness, fatigue, and GI symptoms occur
, with hypokalemia, cardiac complications are the priority per ABCs (Airway-Breathing-Circulation). The
nurse should monitor ECG, notify the provider, and anticipate potassium replacement.
🔹 CONCEPT: GAS EXCHANGE / OXYGENATION
Question 3
A client with pneumonia has ABG results: pH 7.32, PaCO₂ 52 mmHg, HCO₃⁻ 24 mEq/L, PaO₂ 78 mmHg.
Which acid-base imbalance is present?
A) Metabolic acidosis
B) Metabolic alkalosis
C) Respiratory acidosis
D) Respiratory alkalosis
✅ Answer: C
💡 Rationale: Respiratory acidosis is characterized by pH <7.35 and PaCO₂ >45 mmHg, indicating CO₂
retention. This aligns with pneumonia impairing alveolar gas exchange. HCO₃⁻ is normal (22-26 mEq/L),
ruling out a primary metabolic disorder. Respiratory alkalosis (D) would show low PaCO₂; metabolic
acidosis (A) would show low HCO₃⁻; metabolic alkalosis (B) would show high HCO₃⁻.
Question 4
A nurse is caring for a client with a chest tube connected to a water-seal drainage system. Which
finding requires immediate intervention?
A) Intermittent bubbling in the water-seal chamber
B) Continuous bubbling in the water-seal chamber
C) Tidaling in the water-seal chamber with respiration
D) 50 mL of serosanguinous drainage in the collection chamber
✅ Answer: B
💡 Rationale: Continuous bubbling in the water-seal chamber indicates an air leak in the system (e.g.,
loose connection, tubing rupture), which can lead to tension pneumothorax. Intermittent bubbling with
🔹 CONCEPT: FLUID & ELECTROLYTE BALANCE
Question 1
A nurse is assessing a client with a serum sodium level of 128 mEq/L. Which finding should the nurse
expect?
A) Hyperreflexia
B) Confusion and headache
C) Dry, sticky mucous membranes
D) Increased urine specific gravity
✅ Answer: B
💡 Rationale: Hyponatremia (Na⁺ <135 mEq/L) causes water to shift into cells, leading to cerebral
edema. Neurological manifestations like confusion, headache, lethargy, and seizures are priority
findings. Hyperreflexia (A) is associated with hypernatremia or hypocalcemia. Dry mucous membranes
(C) and increased urine specific gravity (D) indicate dehydration/hypernatremia, not hyponatremia.
Question 2
A client receiving IV furosemide for heart failure has a potassium level of 3.1 mEq/L. Which
assessment finding is the nurse's priority?
A) Muscle weakness
B) Cardiac dysrhythmias
C) Nausea and vomiting
D) Fatigue
✅ Answer: B
💡 Rationale: Hypokalemia (K⁺ <3.5 mEq/L) increases risk for life-threatening cardiac dysrhythmias due
to altered myocardial cell membrane potential. While muscle weakness, fatigue, and GI symptoms occur
, with hypokalemia, cardiac complications are the priority per ABCs (Airway-Breathing-Circulation). The
nurse should monitor ECG, notify the provider, and anticipate potassium replacement.
🔹 CONCEPT: GAS EXCHANGE / OXYGENATION
Question 3
A client with pneumonia has ABG results: pH 7.32, PaCO₂ 52 mmHg, HCO₃⁻ 24 mEq/L, PaO₂ 78 mmHg.
Which acid-base imbalance is present?
A) Metabolic acidosis
B) Metabolic alkalosis
C) Respiratory acidosis
D) Respiratory alkalosis
✅ Answer: C
💡 Rationale: Respiratory acidosis is characterized by pH <7.35 and PaCO₂ >45 mmHg, indicating CO₂
retention. This aligns with pneumonia impairing alveolar gas exchange. HCO₃⁻ is normal (22-26 mEq/L),
ruling out a primary metabolic disorder. Respiratory alkalosis (D) would show low PaCO₂; metabolic
acidosis (A) would show low HCO₃⁻; metabolic alkalosis (B) would show high HCO₃⁻.
Question 4
A nurse is caring for a client with a chest tube connected to a water-seal drainage system. Which
finding requires immediate intervention?
A) Intermittent bubbling in the water-seal chamber
B) Continuous bubbling in the water-seal chamber
C) Tidaling in the water-seal chamber with respiration
D) 50 mL of serosanguinous drainage in the collection chamber
✅ Answer: B
💡 Rationale: Continuous bubbling in the water-seal chamber indicates an air leak in the system (e.g.,
loose connection, tubing rupture), which can lead to tension pneumothorax. Intermittent bubbling with
