NCLEX-Style Acid-Base Balance Exam PDF

**NCLEX-Style Acid-Base Balance Exam** **Section 1: Multiple Choice Questions (MCQs)** **Question 1** A patient is admitted with acute respiratory acidosis. Which of the following arterial blood gas (ABG) values would the nurse expect? A. pH 7.30, PaCO2 50 mmHg, HCO3 24 mEq/L\ B. pH 7.50, PaCO2...

**NCLEX-Style Acid-Base Balance Exam** **Section 1: Multiple Choice Questions (MCQs)** **Question 1** A patient is admitted with acute respiratory acidosis. Which of the following arterial blood gas (ABG) values would the nurse expect? A. pH 7.30, PaCO2 50 mmHg, HCO3 24 mEq/L\ B. pH 7.50, PaCO2 30 mmHg, HCO3 22 mEq/L\ C. pH 7.40, PaCO2 45 mmHg, HCO3 26 mEq/L\ D. pH 7.48, PaCO2 37 mmHg, HCO3 30 mEq/L **Answer: A**\ **Rationale:** Respiratory acidosis occurs due to hypoventilation, leading to CO2 retention, resulting in a low pH and high PaCO2. **Question 2** A nurse is caring for a patient experiencing metabolic alkalosis. Which condition is most likely the cause? A. Chronic obstructive pulmonary disease (COPD)\ B. Prolonged vomiting\ C. Diabetic ketoacidosis (DKA)\ D. Acute renal failure **Answer: B**\ **Rationale:** Prolonged vomiting leads to excessive loss of hydrochloric acid, which increases bicarbonate and raises pH, resulting in metabolic alkalosis. **Question 3** Which clinical manifestation is most commonly associated with respiratory alkalosis? A. Kussmaul respirations\ B. Bradycardia\ C. Tingling of fingers and toes\ D. Hypotension **Answer: C**\ **Rationale:** Respiratory alkalosis is caused by hyperventilation, leading to a decrease in CO2 and a rise in pH. Hypocalcemia results, causing tingling and numbness. **Question 4** A patient with metabolic acidosis due to diabetic ketoacidosis is experiencing Kussmaul respirations. What is the primary reason for this respiratory pattern? A. The body is trying to retain CO2 to increase pH\ B. The body is attempting to compensate by decreasing CO2 levels\ C. The body is retaining bicarbonate to increase pH\ D. The body is attempting to increase serum potassium levels **Answer: B**\ **Rationale:** Kussmaul respirations are deep, rapid breaths that help eliminate CO2, which helps increase pH and compensate for metabolic acidosis. **Question 5** Which of the following interventions is the priority for a patient experiencing respiratory acidosis? A. Administer sodium bicarbonate\ B. Encourage slow, deep breaths\ C. Assist with mechanical ventilation if needed\ D. Provide a paper bag for the patient to breathe into **Answer: C**\ **Rationale:** Respiratory acidosis occurs due to hypoventilation. Supporting ventilation (e.g., intubation or noninvasive support) helps remove excess CO2. **Section 2: Select All That Apply (SATA)** **Question 6** A patient with metabolic acidosis may exhibit which of the following signs and symptoms? (Select all that apply.) A. Kussmaul respirations\ B. Confusion\ C. Hypotension\ D. Bradycardia\ E. Nausea and vomiting **Answers: A, B, C, E**\ **Rationale:** Metabolic acidosis leads to Kussmaul respirations (deep and rapid), confusion, hypotension, and gastrointestinal symptoms. Bradycardia is not typical; tachycardia may occur instead. **Question 7** Which of the following can cause respiratory alkalosis? (Select all that apply.) A. Anxiety\ B. Aspirin overdose\ C. Pulmonary embolism\ D. Chronic kidney disease\ E. Mechanical ventilation set too high **Answers: A, B, C, E**\ **Rationale:** Hyperventilation due to anxiety, aspirin toxicity, pulmonary embolism, and excessive mechanical ventilation can lead to respiratory alkalosis. Chronic kidney disease is more likely to cause metabolic acidosis. **Question 8** The nurse is assessing a patient with respiratory acidosis. Which findings are expected? (Select all that apply.) A. Shallow, slow respirations\ B. Hyperkalemia\ C. Increased CO2 retention\ D. Tetany\ E. Confusion **Answers: A, B, C, E**\ **Rationale:** Respiratory acidosis results from CO2 retention, leading to hyperkalemia and neurological symptoms like confusion. Tetany is associated with alkalosis, not acidosis. **Question 9** Which laboratory values are consistent with metabolic alkalosis? (Select all that apply.) A. pH 7.48\ B. HCO3 30 mEq/L\ C. PaCO2 32 mmHg\ D. pH 7.31\ E. PaCO2 48 mmHg **Answers: A, B, E**\ **Rationale:** Metabolic alkalosis presents with an elevated pH and increased bicarbonate. The PaCO2 may be elevated as the lungs compensate. **Question 10** A nurse is teaching a patient about acid-base balance. Which statements are true? (Select all that apply.) A. The kidneys help regulate bicarbonate levels\ B. The lungs help regulate CO2 levels\ C. Compensation by the lungs occurs immediately\ D. Compensation by the kidneys is faster than the lungs\ E. Metabolic alkalosis is often caused by prolonged vomiting **Answers: A, B, C, E**\ **Rationale:** The lungs regulate CO2, and the kidneys regulate bicarbonate. The lungs compensate quickly, while the kidneys take longer. **Section 3: Multiple Choice Questions (MCQs)** **Question 11** A patient presents with an arterial blood gas (ABG) result of pH 7.32, PaCO₂ 50 mmHg, HCO₃ 25 mEq/L. What is the most likely cause of this imbalance? A. Diabetic ketoacidosis\ B. Pneumonia with hypoventilation\ C. Prolonged vomiting\ D. Loop diuretic overuse **Answer: B**\ **Rationale:** A low pH and elevated PaCO₂ indicate respiratory acidosis, which can be caused by hypoventilation due to pneumonia, COPD, or drug overdose. **Question 12** Which patient is at the highest risk for developing metabolic acidosis? A. A patient with severe diarrhea for three days\ B. A patient experiencing an anxiety attack\ C. A patient with chronic obstructive pulmonary disease (COPD)\ D. A patient with prolonged nasogastric suction **Answer: A**\ **Rationale:** Severe diarrhea results in excessive loss of bicarbonate, leading to metabolic acidosis. Prolonged nasogastric suction leads to metabolic alkalosis. **Question 13** A nurse reviews a patient's ABG values: pH 7.50, PaCO₂ 30 mmHg, HCO₃ 24 mEq/L. What condition is present? A. Uncompensated respiratory alkalosis\ B. Uncompensated metabolic alkalosis\ C. Fully compensated metabolic acidosis\ D. Partially compensated metabolic alkalosis **Answer: A**\ **Rationale:** The high pH and low PaCO₂ indicate respiratory alkalosis. The bicarbonate is within the normal range, meaning no metabolic compensation has occurred. **Question 14** A patient is experiencing metabolic alkalosis. Which of the following interventions is appropriate? A. Encourage deep, rapid breathing\ B. Administer sodium bicarbonate\ C. Discontinue nasogastric suctioning if applicable\ D. Restrict potassium intake **Answer: C**\ **Rationale:** Nasogastric suctioning can cause excessive loss of acid, contributing to metabolic alkalosis. Discontinuing it can help correct the imbalance. **Question 15** A nurse is teaching a patient with chronic kidney disease about metabolic acidosis. Which statement by the patient indicates understanding? A. \"My kidneys are holding onto too much bicarbonate.\"\ B. \"I need to breathe slower to help compensate for my condition.\"\ C. \"This condition is caused by my kidneys not removing enough acid.\"\ D. \"I need to increase my CO₂ levels to correct this problem.\" **Answer: C**\ **Rationale:** In chronic kidney disease, the kidneys fail to excrete hydrogen ions, leading to metabolic acidosis. **Question 16** Which ABG result is indicative of fully compensated respiratory acidosis? A. pH 7.37, PaCO₂ 48 mmHg, HCO₃ 30 mEq/L\ B. pH 7.50, PaCO₂ 28 mmHg, HCO₃ 22 mEq/L\ C. pH 7.43, PaCO₂ 30 mmHg, HCO₃ 20 mEq/L\ D. pH 7.48, PaCO₂ 50 mmHg, HCO₃ 30 mEq/L **Answer: A**\ **Rationale:** Fully compensated respiratory acidosis means the pH is within normal range (7.35-7.45), but the PaCO₂ is high and HCO₃ is elevated to compensate. **Question 17** A patient is admitted with respiratory alkalosis. What should the nurse do first? A. Instruct the patient to breathe into a paper bag\ B. Administer sodium bicarbonate\ C. Prepare the patient for intubation\ D. Encourage deep, rapid breathing **Answer: A**\ **Rationale:** Breathing into a paper bag helps retain CO₂, which can help correct respiratory alkalosis caused by hyperventilation. **Question 18** Which electrolyte imbalance is most commonly associated with metabolic alkalosis? A. Hyperkalemia\ B. Hypokalemia\ C. Hypernatremia\ D. Hypercalcemia **Answer: B**\ **Rationale:** Metabolic alkalosis often leads to hypokalemia due to potassium shifting into cells in exchange for hydrogen ions. **Question 19** Which of the following is a primary cause of respiratory acidosis? A. Hyperventilation\ B. Pulmonary embolism\ C. Airway obstruction\ D. Diarrhea **Answer: C**\ **Rationale:** Airway obstruction leads to CO₂ retention, causing respiratory acidosis. **Question 20** A nurse notes an ABG result of pH 7.48, PaCO₂ 38 mmHg, HCO₃ 30 mEq/L. What is the likely cause? A. Diarrhea\ B. Kidney failure\ C. Vomiting\ D. COPD **Answer: C**\ **Rationale:** Vomiting leads to loss of gastric acid, resulting in metabolic alkalosis. **Section 4: Select All That Apply (SATA)** **Question 21** Which patients are at risk for metabolic acidosis? (Select all that apply.) A. A patient with kidney failure\ B. A patient with prolonged vomiting\ C. A patient with salicylate overdose\ D. A patient with severe diarrhea\ E. A patient experiencing hyperventilation **Answers: A, C, D**\ **Rationale:** Kidney failure leads to acid retention, salicylate overdose causes acidosis, and severe diarrhea leads to bicarbonate loss. Vomiting and hyperventilation contribute to alkalosis. **Question 22** A nurse is assessing a patient with respiratory alkalosis. Which symptoms may be present? (Select all that apply.) A. Hyperventilation\ B. Lightheadedness\ C. Muscle cramps\ D. Bradycardia\ E. Numbness and tingling in extremities **Answers: A, B, C, E**\ **Rationale:** Hyperventilation leads to CO₂ loss, causing symptoms like lightheadedness, muscle cramps, and paresthesias. Bradycardia is not typical. **Question 23** A nurse is caring for a patient in metabolic acidosis. Which interventions are appropriate? (Select all that apply.) A. Monitor ABG levels\ B. Administer IV bicarbonate as ordered\ C. Encourage slow, deep breathing\ D. Administer insulin for diabetic ketoacidosis\ E. Monitor serum potassium levels **Answers: A, B, D, E**\ **Rationale:** Monitoring ABGs and potassium is essential. IV bicarbonate is used in severe cases, and insulin treats DKA-induced acidosis. **Question 24** A patient with metabolic alkalosis may experience which clinical manifestations? (Select all that apply.) A. Irritability\ B. Tetany\ C. Slow, shallow respirations\ D. Hyperkalemia\ E. Hypertension **Answers: A, B, C**\ **Rationale:** Metabolic alkalosis leads to neuromuscular excitability (tetany, irritability) and hypoventilation as compensation. **Question 25** A nurse is analyzing ABG results. Which findings indicate respiratory acidosis? (Select all that apply.) A. pH 7.31\ B. PaCO₂ 50 mmHg\ C. HCO₃ 18 mEq/L\ D. pH 7.48\ E. pH 7.38 with PaCO₂ 47 mmHg **Answers: A, B**\ **Rationale:** Respiratory acidosis presents with low pH and high PaCO₂. HCO₃ of 18 indicates metabolic acidosis.