Nursing: A Concept-Based Approach to Learning Vol. 1 & 2, 4e (Pearson)
Module 1 Acid-Base Balance
The Concept of Acid-Base Balance
1) A client who has been fasting and has ketones in the urine is brought to the emergency
department (ED) unconscious. Which acid-base imbalance would the nurse expect to assess in
this client?
A) Metabolic acidosis
B) Respiratory alkalosis
C) Metabolic alkalosis
D) Respiratory acidosis
Answer: A
Explanation: A) A client who is fasting is at risk for development of metabolic acidosis. The
body recognizes fasting as starvation and begins to metabolize its own fatty acids into ketones,
which are metabolic acids.
B) A client who is fasting is at risk for development of metabolic acidosis. The body recognizes
fasting as starvation and begins to metabolize its own fatty acids into ketones, which are
metabolic acids. Starvation would not result in respiratory alkalosis.
C) A client who is fasting is at risk for development of metabolic acidosis. The body recognizes
fasting as starvation and begins to metabolize its own fatty acids into ketones, which are
metabolic acids. Starvation would not result in metabolic alkalosis.
D) A client who is fasting is at risk for development of metabolic acidosis. The body recognizes
fasting as starvation and begins to metabolize its own fatty acids into ketones, which are
metabolic acids. Starvation would not result in respiratory acidosis.
Page Ref: 5
Cognitive Level: Analyzing
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Competencies: 2.4 Diagnose actual or potential health
problems and needs. | NLN Competencies: Knowledge and Science: Relationships between
knowledge/science and quality and safe patient care. | Nursing Process: Assessment
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
1
Copyright © 2023 Pearson Education, Inc.
,2) The nurse is caring for a client in the emergency department. Which factors will the nurse
identify that increase the client's risk for metabolic acidosis? Select all that apply.
A) Abdominal fistulas
B) Chronic obstructive pulmonary disease
C) Pneumonia
D) Chronic renal failure
E) Hypovolemic shock
Answer: A, D, E
Explanation: A) Metabolic acidosis is rarely a primary disorder. It usually develops during the
course of another condition such as an abdominal fistula which can cause the loss of bicarbonate
from the intestine.
B) Chronic obstructive pulmonary disease places the client at risk for respiratory acidosis with
the increased retention of carbon dioxide in the blood.
C) Pneumonia places the client at risk for respiratory acidosis with the increased retention of
carbon dioxide in the blood.
D) Metabolic acidosis is rarely a primary disorder. It usually develops during the course of
another condition such as chronic renal failure. In this health problem, the kidneys are unable to
excrete a normal amount of hydrogen ions in the urine. This results in an excessive amount of
hydrogen ions in the blood, which produces metabolic acidosis.
E) Metabolic acidosis is rarely a primary disorder. It usually develops during the course of
another condition such as hypovolemic shock. With a severe blood loss, there is a lack of blood
flow throughout the body and a lack of oxygen in every cell. Adenosine triphosphate (ATP) must
produce energy anaerobically without the presence of oxygen; lactic acid is a by-product. This
produces systemic lactic acidosis, a type of metabolic acidosis.
Page Ref: 5-6
Cognitive Level: Applying
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Competencies: 2.4 Diagnose actual or potential health
problems and needs. | NLN Competencies: Knowledge and Science: Relationships between
knowledge/science and quality and safe patient care. | Nursing Process: Assessment
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
2
Copyright © 2023 Pearson Education, Inc.
,3) A client with acute asthma has a PaCO2 of 48 mmHg, a pH of 7.31, and a normal HCO3
arterial blood gas value. Which condition will the nurse associate with these values?
A) Metabolic acidosis
B) Respiratory alkalosis
C) Respiratory acidosis
D) Metabolic alkalosis
Answer: C
Explanation: A) Uncompensated metabolic acidosis has a decreased pH, normal PaCO2, and
decreased HCO3.
B) Uncompensated respiratory alkalosis has an increased pH, decreased PaCO2, and normal
HCO3.
C) If the pH is decreased and the PaCO2 is increased with a normal HCO3, it is uncompensated
respiratory acidosis.
D) Uncompensated metabolic alkalosis has an increased pH, normal PaCO2, and increased
HCO3.
Page Ref: 7
Cognitive Level: Analyzing
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Essential Competencies: 2.4 Diagnose actual or potential
health problems and needs. | NLN Competencies: Knowledge and Science: Relationships
between knowledge/science and quality and safe patient care. | Nursing Process: Assessment
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
3
Copyright © 2023 Pearson Education, Inc.
, 4) The nurse is reviewing the latest arterial blood gas results for a client with metabolic alkalosis.
Which result indicates that the metabolic alkalosis is compensated?
A) pH 7.32
B) PaCO2 18 mmHg
C) HCO3 8 mEq/L
D) PaCO2 48 mmHg
Answer: D
Explanation: A) A normal pH level is 7.35-7.45. A pH of less than 7.35 is acidosis.
B) A PaCO2 level of 18 mmHg is low and is seen in respiratory alkalosis.
C) A HCO3 level of 8 mEq/L is low and is most likely associated with metabolic acidosis.
D) In metabolic alkalosis, there is an excess of bicarbonate. To compensate for this imbalance,
the rate and depth of respirations decrease, leading to retention of carbon dioxide. The PaCO2
will be elevated.
Page Ref: 8
Cognitive Level: Analyzing
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Essential Competencies: 2.4 Diagnose actual or potential
health problems and needs. | NLN Competencies: Knowledge and Science: Relationships
between knowledge/science and quality and safe patient care. | Nursing Process: Evaluation
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
4
Copyright © 2023 Pearson Education, Inc.
Module 1 Acid-Base Balance
The Concept of Acid-Base Balance
1) A client who has been fasting and has ketones in the urine is brought to the emergency
department (ED) unconscious. Which acid-base imbalance would the nurse expect to assess in
this client?
A) Metabolic acidosis
B) Respiratory alkalosis
C) Metabolic alkalosis
D) Respiratory acidosis
Answer: A
Explanation: A) A client who is fasting is at risk for development of metabolic acidosis. The
body recognizes fasting as starvation and begins to metabolize its own fatty acids into ketones,
which are metabolic acids.
B) A client who is fasting is at risk for development of metabolic acidosis. The body recognizes
fasting as starvation and begins to metabolize its own fatty acids into ketones, which are
metabolic acids. Starvation would not result in respiratory alkalosis.
C) A client who is fasting is at risk for development of metabolic acidosis. The body recognizes
fasting as starvation and begins to metabolize its own fatty acids into ketones, which are
metabolic acids. Starvation would not result in metabolic alkalosis.
D) A client who is fasting is at risk for development of metabolic acidosis. The body recognizes
fasting as starvation and begins to metabolize its own fatty acids into ketones, which are
metabolic acids. Starvation would not result in respiratory acidosis.
Page Ref: 5
Cognitive Level: Analyzing
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Competencies: 2.4 Diagnose actual or potential health
problems and needs. | NLN Competencies: Knowledge and Science: Relationships between
knowledge/science and quality and safe patient care. | Nursing Process: Assessment
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
1
Copyright © 2023 Pearson Education, Inc.
,2) The nurse is caring for a client in the emergency department. Which factors will the nurse
identify that increase the client's risk for metabolic acidosis? Select all that apply.
A) Abdominal fistulas
B) Chronic obstructive pulmonary disease
C) Pneumonia
D) Chronic renal failure
E) Hypovolemic shock
Answer: A, D, E
Explanation: A) Metabolic acidosis is rarely a primary disorder. It usually develops during the
course of another condition such as an abdominal fistula which can cause the loss of bicarbonate
from the intestine.
B) Chronic obstructive pulmonary disease places the client at risk for respiratory acidosis with
the increased retention of carbon dioxide in the blood.
C) Pneumonia places the client at risk for respiratory acidosis with the increased retention of
carbon dioxide in the blood.
D) Metabolic acidosis is rarely a primary disorder. It usually develops during the course of
another condition such as chronic renal failure. In this health problem, the kidneys are unable to
excrete a normal amount of hydrogen ions in the urine. This results in an excessive amount of
hydrogen ions in the blood, which produces metabolic acidosis.
E) Metabolic acidosis is rarely a primary disorder. It usually develops during the course of
another condition such as hypovolemic shock. With a severe blood loss, there is a lack of blood
flow throughout the body and a lack of oxygen in every cell. Adenosine triphosphate (ATP) must
produce energy anaerobically without the presence of oxygen; lactic acid is a by-product. This
produces systemic lactic acidosis, a type of metabolic acidosis.
Page Ref: 5-6
Cognitive Level: Applying
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Competencies: 2.4 Diagnose actual or potential health
problems and needs. | NLN Competencies: Knowledge and Science: Relationships between
knowledge/science and quality and safe patient care. | Nursing Process: Assessment
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
2
Copyright © 2023 Pearson Education, Inc.
,3) A client with acute asthma has a PaCO2 of 48 mmHg, a pH of 7.31, and a normal HCO3
arterial blood gas value. Which condition will the nurse associate with these values?
A) Metabolic acidosis
B) Respiratory alkalosis
C) Respiratory acidosis
D) Metabolic alkalosis
Answer: C
Explanation: A) Uncompensated metabolic acidosis has a decreased pH, normal PaCO2, and
decreased HCO3.
B) Uncompensated respiratory alkalosis has an increased pH, decreased PaCO2, and normal
HCO3.
C) If the pH is decreased and the PaCO2 is increased with a normal HCO3, it is uncompensated
respiratory acidosis.
D) Uncompensated metabolic alkalosis has an increased pH, normal PaCO2, and increased
HCO3.
Page Ref: 7
Cognitive Level: Analyzing
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Essential Competencies: 2.4 Diagnose actual or potential
health problems and needs. | NLN Competencies: Knowledge and Science: Relationships
between knowledge/science and quality and safe patient care. | Nursing Process: Assessment
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
3
Copyright © 2023 Pearson Education, Inc.
, 4) The nurse is reviewing the latest arterial blood gas results for a client with metabolic alkalosis.
Which result indicates that the metabolic alkalosis is compensated?
A) pH 7.32
B) PaCO2 18 mmHg
C) HCO3 8 mEq/L
D) PaCO2 48 mmHg
Answer: D
Explanation: A) A normal pH level is 7.35-7.45. A pH of less than 7.35 is acidosis.
B) A PaCO2 level of 18 mmHg is low and is seen in respiratory alkalosis.
C) A HCO3 level of 8 mEq/L is low and is most likely associated with metabolic acidosis.
D) In metabolic alkalosis, there is an excess of bicarbonate. To compensate for this imbalance,
the rate and depth of respirations decrease, leading to retention of carbon dioxide. The PaCO2
will be elevated.
Page Ref: 8
Cognitive Level: Analyzing
Client Need/Sub: Physiological Integrity: Physiological Adaptation
Standards: QSEN Competencies: III.A.1. Demonstrate knowledge of basic scientific methods
and processes. | AACN Domains and Essential Competencies: 2.4 Diagnose actual or potential
health problems and needs. | NLN Competencies: Knowledge and Science: Relationships
between knowledge/science and quality and safe patient care. | Nursing Process: Evaluation
Learning Outcome: 1.2. Differentiate alterations in acid-base balance.
MNL LO: Analyze the concept of acid-base balance and its application to nursing care.
4
Copyright © 2023 Pearson Education, Inc.
