ACID-BASE BALANCE PRACTICE EXAM 2026 – 300+ Questions with Verified
Answers and Detailed Rationales Covering Metabolic and Respiratory Acidosis and
Alkalosis
About this resource:
Arterial blood gas (ABG) interpretation is one of the most critical, high-stakes skills in healthcare.
Whether you are a nursing student preparing for the NCLEX, a medical student tackling USMLE Step 1, a
respiratory therapy student, or a critical care nurse managing ventilated patients, mastering acid-base
balance is non-negotiable. It is the difference between recognizing life-threatening metabolic
derangements and missing a patient in crisis.
1) The nurse is analyzing the client's arterial blood gas report, which reveals a pH of 6.58. The client has
just suffered a cardiac arrest. Which of the following consequences does the nurse consider for this
client?
A) Decreased cardiac output
B) Increase magnesium levels
C) Decreased free calcium in the ECT
D) Increased myocardial contractility - answer-Answer: A
Explanation: A) The nurse knows that severe acidosis (pH of 7.0 or less) depresses myocardial
contractility, which leads to decreased cardiac output. Acid-base imbalances also affect electrolyte
balance. In acidosis, potassium is retained as the kidney excretes excess hydrogen ion. Excess hydrogen
ions also enter the cells, displacing potassium from the intracellular space to maintain the balance of
cations and anions within the cells. The effect of both processes is to increase serum potassium levels.
Also in acidosis, calcium is released from its bonds with plasma proteins, increasing the amount of
ionized (free) calcium in the blood. Magnesium levels may fall in acidosis.
2) The mother of a 1-month-old infant calls the nurse who works in the health clinic. The mother is
concerned because the infant has had vomiting and diarrhea for 2 days. The nurse knows that this infant
is at risk for metabolic acidosis. Which of the following is the priority nursing action? A) Instruct the
mother to provide the infant with 50 mL of glucose water.
B) Instruct the mother to measure the infant's urine output for 24 hours.
C) Instruct the mother to give the infant at least 2 ounces of juice every 2 hours.
D) Instruct the mother to bring the infant to the clinic for evaluation. - answer-Answer: D
Explanation: D) Parents and caregivers need to be taught the seriousness of vomiting or diarrhea in
infants due to rapid fluid loss that can occur in this age group. They should also be taught the
,importance of bringing an infant in this situation to healthcare providers for evaluation. Encouraging
fluids for an infant who is actively vomiting will not improve fluid balance status, and neither juice nor
glucose water is the best choice of fluid. Simply monitoring the loss over the next 24 hours would
increase the potential for the infant to become dehydrated.
3) The nurse is assessing an African-American client whose cultural background is different from the
cultural background of the nurse. The client has symptoms of metabolic acidosis. Which of the following
situations would illustrate stereotypical behavior on the nurse's part?
Select all that apply.
A) Understanding that all culture members will have the same beliefs
B) Bringing previous negative information and experiences into this situation
C) Making an assumption that all members of each culture are alike
D) Taking general knowledge from literature and applying it to the situation
E) Discussing the client's health status with family members - answer-Answer: A, B, C, D
Explanation: A,B,C,D) Options 1, 2, 3, and 4 describe stereotypical behavior, which is assuming that all
members of a culture or ethnic group are alike. Option 2 describes prejudice. Prejudice is a negative
belief or preference that is generalized about a group, which leads to "prejudgment." Prejudice occurs
when the person making the judgment generalizes an experience of one individual from a culture to all
members of that group. Discussing the client's health status with family members is not stereotypical
behavior and would be considered a violation of the privacy laws if the client did not provide permission
for disclosure of personal health information.
4) The nurse is caring for a client who has been admitted with persistent diarrhea lasting 3 days. Which
of the following are appropriate nursing diagnoses for this client during the acute phase of the illness?
Select all that apply.
A) Decreased Cardiac Output
B) Ineffective Airway Clearance
C) Deficient Fluid Volume
D) Knowledge Deficit
E) Risk for Injury - answer-Answer: A, E
Explanation: Metabolic acidosis affects cardiac output by decreasing contractility, slowing the heart rate,
and increasing the risk for dysrhythmias. Appropriate nursing diagnoses during the acute phase of illness
are Risk for Injury and Decreased Cardiac Output. The client may have a knowledge deficit but this is not
,an appropriate nursing diagnosis during the acute phase of the illness. The client with metabolic acidosis
will be at risk for developing an Excessive Fluid Volume, not a Deficient Fluid Volume. The client with
metabolic acidosis is not at risk for Ineffective Airway Clearance.
5) The nurse is caring for a client with metabolic acidosis. Which of the following are appropriate goals
for this client?
Select all that apply.
A) The client will maintain a respiratory rate of 30 or more.
B) The client will describe preventative measure for the underlying chronic illness.
C) The client will maintain baseline cardiac rhythm.
D) pH will range from 7.25 to 7.35.
E) The client will take potassium supplements to increase potassium levels. - answer-Answer: B, C
Explanation: Planning for the client with metabolic acidosis involves identification and treatment of the
underlying cause and restoration and maintenance of acid-base balance. The client should be able to
describe preventative measures for the underlying chronic illness that caused the metabolic acidosis to
occur and maintain the baseline cardiac rhythm. The pH should be maintained between 7.35 and 7.45.
The client's respiratory rate should be within normal range for age and condition. Taking a potassium
supplement may cause hyperkalemia, which decreases cardiac output and worsens metabolic acidosis.
6) The nurse is caring for a client admitted with renal failure and metabolic acidosis. Which of the
following signs would indicate to the nurse that planned interventions to relieve the metabolic acidosis
have been effective?
A) Decreased respiratory depth
B) Palpitations
C) Increased deep tendon reflexes
D) Respiratory rate of 38 - answer-Answer: A
Explanation: The client with metabolic acidosis will have an increased respiratory rate and depth. Signs
that care has been effective would include a decrease in the rate and depth of respirations. An increased
respiratory rate, as indicated by a respiratory rate of 38, would indicate continued metabolic acidosis.
Increased deep tendon reflexes and palpitations are not associated with metabolic acidosis.
7) The nurse is caring for the client experiencing hypovolemic shock and metabolic acidosis. Which of
the following therapies would the nurse question if planned for this client?
Select all that apply.
, A) Monitor weight on admission and discharge.
B) Monitor ECG for conduction problems.
C) Limit the intake of fluids.
D) Administer sodium bicarbonate.
E) Keep the bed in the locked and low position. - answer-Answer: A, C
Explanation: The treatment for hypovolemic shock would include the administration of fluids, not
limiting fluids. Patients being treated for hypovolemia will require daily weights, not a weight on
admission and then discharge. Administering sodium bicarbonate and monitoring ECGs are appropriate
for the client with shock. The client recovering from hypovolemic shock is at risk for injury, so the bed
should be kept in the locked and low position.
8) A client with metabolic acidosis has been admitted to the unit from the Emergency Department. The
client is experiencing confusion and weakness. Which of the following does the nurse implement as a
priority of care for this client?
A) Place the client in a high-Fowler's position.
B) Protect the client from injury.
C) Administer sodium bicarbonate.
D) Give the client skin care. - answer-Answer: B
Explanation: The client with metabolic acidosis may have symptoms of drowsiness, lethargy, confusion,
and weakness. A priority of care would be preventing injury to the client. Medication administration is a
physician order. Skin care would not be a priority on admission. The high-Fowler's position would not be
the safest position for the confused client.
9) The nurse is preparing to instruct a client with type 1 diabetes mellitus on the mechanism behind the
development of ketoacidosis. List the order in which the nurse should provide this information.
1. Production of lactate and hydrogen ions
2. Development of lactic acidosis
3. Breakdown of fatty tissue
4. Reduction in intracellular glucose
5. Fatty acids converted to ketones - answer-Answer: 2, 1, 4, 3, 5
Explanation:
1. Lactic acidosis develops due to tissue hypoxia and a shift to anaerobic metabolism by the cells. Lactate
and hydrogen ions are produced, forming lactic acid. Starvation or lack of insulin leads to intracellular
Answers and Detailed Rationales Covering Metabolic and Respiratory Acidosis and
Alkalosis
About this resource:
Arterial blood gas (ABG) interpretation is one of the most critical, high-stakes skills in healthcare.
Whether you are a nursing student preparing for the NCLEX, a medical student tackling USMLE Step 1, a
respiratory therapy student, or a critical care nurse managing ventilated patients, mastering acid-base
balance is non-negotiable. It is the difference between recognizing life-threatening metabolic
derangements and missing a patient in crisis.
1) The nurse is analyzing the client's arterial blood gas report, which reveals a pH of 6.58. The client has
just suffered a cardiac arrest. Which of the following consequences does the nurse consider for this
client?
A) Decreased cardiac output
B) Increase magnesium levels
C) Decreased free calcium in the ECT
D) Increased myocardial contractility - answer-Answer: A
Explanation: A) The nurse knows that severe acidosis (pH of 7.0 or less) depresses myocardial
contractility, which leads to decreased cardiac output. Acid-base imbalances also affect electrolyte
balance. In acidosis, potassium is retained as the kidney excretes excess hydrogen ion. Excess hydrogen
ions also enter the cells, displacing potassium from the intracellular space to maintain the balance of
cations and anions within the cells. The effect of both processes is to increase serum potassium levels.
Also in acidosis, calcium is released from its bonds with plasma proteins, increasing the amount of
ionized (free) calcium in the blood. Magnesium levels may fall in acidosis.
2) The mother of a 1-month-old infant calls the nurse who works in the health clinic. The mother is
concerned because the infant has had vomiting and diarrhea for 2 days. The nurse knows that this infant
is at risk for metabolic acidosis. Which of the following is the priority nursing action? A) Instruct the
mother to provide the infant with 50 mL of glucose water.
B) Instruct the mother to measure the infant's urine output for 24 hours.
C) Instruct the mother to give the infant at least 2 ounces of juice every 2 hours.
D) Instruct the mother to bring the infant to the clinic for evaluation. - answer-Answer: D
Explanation: D) Parents and caregivers need to be taught the seriousness of vomiting or diarrhea in
infants due to rapid fluid loss that can occur in this age group. They should also be taught the
,importance of bringing an infant in this situation to healthcare providers for evaluation. Encouraging
fluids for an infant who is actively vomiting will not improve fluid balance status, and neither juice nor
glucose water is the best choice of fluid. Simply monitoring the loss over the next 24 hours would
increase the potential for the infant to become dehydrated.
3) The nurse is assessing an African-American client whose cultural background is different from the
cultural background of the nurse. The client has symptoms of metabolic acidosis. Which of the following
situations would illustrate stereotypical behavior on the nurse's part?
Select all that apply.
A) Understanding that all culture members will have the same beliefs
B) Bringing previous negative information and experiences into this situation
C) Making an assumption that all members of each culture are alike
D) Taking general knowledge from literature and applying it to the situation
E) Discussing the client's health status with family members - answer-Answer: A, B, C, D
Explanation: A,B,C,D) Options 1, 2, 3, and 4 describe stereotypical behavior, which is assuming that all
members of a culture or ethnic group are alike. Option 2 describes prejudice. Prejudice is a negative
belief or preference that is generalized about a group, which leads to "prejudgment." Prejudice occurs
when the person making the judgment generalizes an experience of one individual from a culture to all
members of that group. Discussing the client's health status with family members is not stereotypical
behavior and would be considered a violation of the privacy laws if the client did not provide permission
for disclosure of personal health information.
4) The nurse is caring for a client who has been admitted with persistent diarrhea lasting 3 days. Which
of the following are appropriate nursing diagnoses for this client during the acute phase of the illness?
Select all that apply.
A) Decreased Cardiac Output
B) Ineffective Airway Clearance
C) Deficient Fluid Volume
D) Knowledge Deficit
E) Risk for Injury - answer-Answer: A, E
Explanation: Metabolic acidosis affects cardiac output by decreasing contractility, slowing the heart rate,
and increasing the risk for dysrhythmias. Appropriate nursing diagnoses during the acute phase of illness
are Risk for Injury and Decreased Cardiac Output. The client may have a knowledge deficit but this is not
,an appropriate nursing diagnosis during the acute phase of the illness. The client with metabolic acidosis
will be at risk for developing an Excessive Fluid Volume, not a Deficient Fluid Volume. The client with
metabolic acidosis is not at risk for Ineffective Airway Clearance.
5) The nurse is caring for a client with metabolic acidosis. Which of the following are appropriate goals
for this client?
Select all that apply.
A) The client will maintain a respiratory rate of 30 or more.
B) The client will describe preventative measure for the underlying chronic illness.
C) The client will maintain baseline cardiac rhythm.
D) pH will range from 7.25 to 7.35.
E) The client will take potassium supplements to increase potassium levels. - answer-Answer: B, C
Explanation: Planning for the client with metabolic acidosis involves identification and treatment of the
underlying cause and restoration and maintenance of acid-base balance. The client should be able to
describe preventative measures for the underlying chronic illness that caused the metabolic acidosis to
occur and maintain the baseline cardiac rhythm. The pH should be maintained between 7.35 and 7.45.
The client's respiratory rate should be within normal range for age and condition. Taking a potassium
supplement may cause hyperkalemia, which decreases cardiac output and worsens metabolic acidosis.
6) The nurse is caring for a client admitted with renal failure and metabolic acidosis. Which of the
following signs would indicate to the nurse that planned interventions to relieve the metabolic acidosis
have been effective?
A) Decreased respiratory depth
B) Palpitations
C) Increased deep tendon reflexes
D) Respiratory rate of 38 - answer-Answer: A
Explanation: The client with metabolic acidosis will have an increased respiratory rate and depth. Signs
that care has been effective would include a decrease in the rate and depth of respirations. An increased
respiratory rate, as indicated by a respiratory rate of 38, would indicate continued metabolic acidosis.
Increased deep tendon reflexes and palpitations are not associated with metabolic acidosis.
7) The nurse is caring for the client experiencing hypovolemic shock and metabolic acidosis. Which of
the following therapies would the nurse question if planned for this client?
Select all that apply.
, A) Monitor weight on admission and discharge.
B) Monitor ECG for conduction problems.
C) Limit the intake of fluids.
D) Administer sodium bicarbonate.
E) Keep the bed in the locked and low position. - answer-Answer: A, C
Explanation: The treatment for hypovolemic shock would include the administration of fluids, not
limiting fluids. Patients being treated for hypovolemia will require daily weights, not a weight on
admission and then discharge. Administering sodium bicarbonate and monitoring ECGs are appropriate
for the client with shock. The client recovering from hypovolemic shock is at risk for injury, so the bed
should be kept in the locked and low position.
8) A client with metabolic acidosis has been admitted to the unit from the Emergency Department. The
client is experiencing confusion and weakness. Which of the following does the nurse implement as a
priority of care for this client?
A) Place the client in a high-Fowler's position.
B) Protect the client from injury.
C) Administer sodium bicarbonate.
D) Give the client skin care. - answer-Answer: B
Explanation: The client with metabolic acidosis may have symptoms of drowsiness, lethargy, confusion,
and weakness. A priority of care would be preventing injury to the client. Medication administration is a
physician order. Skin care would not be a priority on admission. The high-Fowler's position would not be
the safest position for the confused client.
9) The nurse is preparing to instruct a client with type 1 diabetes mellitus on the mechanism behind the
development of ketoacidosis. List the order in which the nurse should provide this information.
1. Production of lactate and hydrogen ions
2. Development of lactic acidosis
3. Breakdown of fatty tissue
4. Reduction in intracellular glucose
5. Fatty acids converted to ketones - answer-Answer: 2, 1, 4, 3, 5
Explanation:
1. Lactic acidosis develops due to tissue hypoxia and a shift to anaerobic metabolism by the cells. Lactate
and hydrogen ions are produced, forming lactic acid. Starvation or lack of insulin leads to intracellular
