Deck 7: Acid-Base Balance and Regulation

Question 1

Under normal conditions, what is the ratio between bicarbonate ions and H₂CO₃ in arterial blood?

A) 10:1
B) 1:10
C) 1:20
D) 1:20

Answer 1

D

Question 2

What is the body's most effective acid-base balance monitor and regulator?

A) respiratory system
B) pons
C) renal system
D) peripheral chemoreceptors

Answer 2

C

Question 3

What is defined as a proton acceptor?

A) protein
B) buffer
C) base
D) acid

Answer 3

C

Question 4

What equation mathematically illustrates how the pH of a solution is influenced by the base to acid ratio?

A) H-H equation
B) H-C equation
C) A-H equation
D) A-A equation

Question 5

Which of the following are considered to be weak bases?
I. Bicarbonate ion
II. Sodium Hydroxide
III. Magnesium Hydroxide

A) II and III only
B) I, II, and III
C) I and III only
D) I only

Question 6

How many minutes does it take for the respiratory system to offset acidosis or alkalosis?

A) 1-3 minutes
B) 2-4 minutes
C) 6-8 minutes
D) 3-5 minutes

Question 7

What is the normal pH range for venous blood?

A) 7.30-7.40
B) 7.25-7.35
C) 7.35-7.45
D) 7.40-7.50

Question 8

What directly relates to the acidity of a solution?

A) concentration of bound anions
B) concentration of free electrons
C) concentration of bound protons
D) concentration of free protons

Question 9

What is defined as the negative logarithm of the hydrogen ion concentration?

A) buffer
B) pH
C) acid
D) HCO₃-

Question 10

Which of the following is defined as a proton donor?

A) base
B) buffer
C) acid
D) protein

Question 11

How would the pH of pure water be expressed?

A) 0
B) 10 ^-7 mol/L
C) 10 ^-7 mol/L
D) 10 ^-7 mol/L

Question 12

What does an arterial pH of 7.30 indicate?

A) acidosis or acidemia
B) normal arterial value
C) insufficient information to assess
D) alkalosis or alkalemia

Question 13

Below what pH is a solution considered acidic?

A) 9
B) 3
C) 5
D) 7

Question 14

What does an arterial pH of 7.48 indicate?

A) normal pH
B) insufficient information to assess
C) alkalosis or aklalemia
D) acidosis or acidemia

Question 15

Which of the following are examples of weak acids?
I) Acetic acid
II) Hydrochloric acid
III) Carbonic acid

A) II only
B) I and III only
C) I and III only
D) I and III only

Question 16

What substances are released when carbonic acid dissociates?

A) bicarbonate ions and proteins
B) bicarbonate ions and OH-
C) bicarbonate ions and OH-
D) bicarbonate ions and water

Question 17

What is the term for substance that dissociates completely in water to liberate all of the H+?

A) strong base
B) weak acid
C) weak base
D) strong acid

Question 18

What is the normal range for pH of arterial blood?

A) 7.35-7.45
B) 7.20-7.30
C) 7.30-7.40
D) 7.45-7.55

Question 19

What is the term for the ability of an acid-base mixture to resist sudden changes in pH?

A) ionization coefficient
B) buffer action
C) ionization rate
D) dissociation coefficient

Question 20

What is the first line of defense in acid-base regulation?

A) respiratory system
B) hepatic system
C) chemical buffer system
D) renal system

Question 21

When acute ventilatory failure with complete partial renal compensation is present, which of the following would be true?

A) PCO2 above normal range, pH below normal range, HCO3- within normal range
B) PCO2 above normal range, pH within normal range, HCO3 above normal range
C) PCO2 above normal, pH within normal range, HCO3 below normal range
D) PCO2 above normal range, pH below normal range, HCO3-above normal range

Question 22

In relationship to acid-base balance, which molecules can be amphoteric?

A) hydoxyl molecules
B) protein molecules
C) phosphate molecules
D) bicarbonate molecules

Question 23

Compared to the carbonic acid-bicarbonate buffering system in extracellular fluid, how effective is the phosphate buffering system?

A) about twice as effective
B) about 6 times more effective
C) about one-sixth as effective
D) about half as effective

Question 24

Which of the following systems are capable of regulating alkaline substances in the blood and restoring chemical buffers used in managing the H+ levels in extracellular fluids?
I. Phosphate buffer system
II. Protein buffer system
III. Respiratory system
IV. Renal system

A) III and IV only
B) IV only
C) III only
D) I and II only

Question 25

What is another term for acute ventilatory failure with partial renal compensation?

A) partially compensated respiratory acidosis
B) acute alveolar hyperventilation
C) chronic alveolar hyperventilation
D) compensated respiratory acidosis

Question 26

What are the primary components of the phosphate buffer system?
I. sodium salts of dihydrogen phosphate
II. sodium salts of monohydrogen phosphate
III. sodium salts of trihydrogen phosphate

A) II and III only
B) I and II only
C) I, II, and III
D) I only

Question 27

How does the ability of carbonic acid in changing the blood pH compare to that of the bicarbonate ion?

A) six times more powerful
B) twenty times more powerful
C) one-twentieth as powerful
D) one-sixth as powerful

Question 28

What is the term for the situation that exists when the volume of CO₂ eliminated from the lungs is less than the volume of CO₂ produced at the tissue cells?

A) hypoventilation
B) hyperperfusion
C) hyperventilation
D) hypoperfusion

Question 29

Which of the following systems are capable of eliminating fixed acids?
I. Phosphate buffer system
II. Protein buffer system
III. Respiratory system
IV. Renal system

A) IV only
B) I, II, and IV only
C) III and IV only
D) I and II only

Question 30

When partially compensated respiratory acidosis is present, which of the following would be true?

A) PCO2 above normal, pH within normal range, HCO3 below normal range
B) PCO2 above normal range, pH below normal range, HCO3- within normal range
C) PCO2 above normal range, pH below normal range, HCO3-above normal range
D) PCO2 above normal range, pH within normal range, HCO3 within normal range

Question 31

If the bicarbonate to carbonic acid ratio is 30 and the log of 30 equals 1.48), what would the pH equal?

A) pH would be 7.58
B) pH would be 7.148
C) insufficient information to calculate
D) pH would be 7.48

Question 32

If the pH is 7.20 and the PaCO2 is 80 mmHg, what would the HCO3- equal if the "rule of thumb" is applied?

A) 20 mEq/L
B) 28 mEq/L
C) 24 mEq/L
D) 26 mEq/L

Question 33

What is the body's most abundant and influential buffering system?

A) hepatic buffering system
B) phosphate buffer system
C) carbonic acid-bicarbonate buffer system
D) protein buffer system

Question 34

When acute ventilatory failure is present, which of the following would be true?

A) PCO2 above normal range, pH below normal range, HCO3- within normal range
B) PCO2 above normal range, pH within normal range, HCO3 within normal range
C) PCO2 above normal, pH within normal range, HCO3 below normal range
D) PCO2 above normal range, pH below normal range, HCO3-above normal range

Question 35

Which of the following conditions are associated with chronic ventilatory failure?
I. COPD
II. Histoplasmosis
III. Kyphoscoliosis
IV. Chronic tuberculosis

A) I and IV only
B) I, II, and III only
C) I, II, III, and IV
D) I only

Question 36

If the bicarbonate to carbonic acid ratio is 15 and the log 15 equals 1.176), what would the pH equal?

A) pH would be 7.18
B) insufficient information to calculate
C) pH would be 7.28
D) pH would be 7.28

Question 37

Which system has up to two times the buffering power of all of the chemical buffering systems combined?

A) renal system
B) hepatic buffering system
C) respiratory system
D) gastric buffering system

Question 38

What percentage of the buffering power of body fluids is found in intercellular proteins?

A) 75%
B) 25%
C) 10%
D) 50%

Question 39

In the H-H equation, what value can be substituted for carbonic acid?

A) PCO2 x 0.003
B) PCO2 x 0.03
C) PCO2 x 0.03
D) PCO2 x 0.03

Question 40

When chronic ventilatory failure with complete renal compensation is present, which of the following will be within normal limits?
I. PaCO₂
II. pH
III. HCO₃-

A) II only
B) II and III only
C) I and II only
D) I , II, and III

Question 41

Which of the following are common causes of acute alveolar hyperventilation?
I. Hypoxia
II. Brain inflammation
III. Stimulant drugs
IV. Pain, anxiety, and fear

A) I, II and III only
B) II, III, and IV only
C) I , II, III, and IV
D) I, II, and III

Question 42

What of the following can be used to determine the underlying cause of metabolic acidosis?

A) ABG
B) liver enzyme panel
C) anion gap
D) urinalysis

Question 43

What is the alternate name of the acid base abnormality resulting from a decreased HCO3-?

A) hyperchloremic metabolic alkalosis
B) hyperchloremic metabolic acidosis
C) hypernatremic metabolic alkalosis
D) hypernatremic metabolic acidosis

Question 44

Which of the following would occur in partially compensated metabolic acidosis?

A) pH would be above normal limits and PaCO2 and HCO3- would be below normal range
B) pH, PaCO2, and HCO3- would be below normal limits
C) pH would be above normal limits, PaCO2 would be above normal range, and HCO3- would be below normal range
D) pH would be normal and PaCO2 and HCO3- would be below normal limits

Question 45

Why does a patient with CO poisoning have cherry red skin coloring instead of cyanosis?

A) CO poisons the hemoglobin and chemical alters the erythrocyte making it incapable of carrying oxygen. The red color is due to compensatory polycythemia which occurs immediately.
B) CO causes the hemoglobin molecule to break apart. The red coloration is from the hemoglobin fragments under the skin
C) Patients with CO poisoning hyperventilate so the red coloration is due to the increased WOB
D) CO rapidly fills sites on the hemoglobin where oxygen normally attaches. The high level of carboxyhemoglobin and saturated hemoglobin results in the red coloration

Question 46

How does the body correct for alveolar hyperventilation?

A) respiratory acidosis
B) metabolic acidosis
C) metabolic alkalosis
D) It can't without the administration of supplemental oxygen

Question 47

What is the most common cause of acute respiratory alkalosis?

A) hypoxemia
B) pneumothorax
C) fear and anxiety
D) pain

Question 48

What is the fourth leading cause of death in the United States?

A) diabetes
B) COPD
C) cardiovascular disease
D) cancer

Question 49

Which of the following can cause acute ventilatory failure?
I. Guillian-Barre syndrome
II. General anesthesia
III. Head trauma
IV. Myasthenia gravis

A) I, II, III, and IV
B) I, II, and IV only
C) II and III only
D) I and IV only

Question 50

Which acid base abnormality is suspected when a patient presents with Kussmaul's breathing and a fruity breath odor?

A) metabolic acidosis
B) metabolic alkalosis
C) respiratory alkalosis
D) respiratory acidosis

Question 51

When chronic alveolar hyperventilation is completely compensated, which of the following would occur?

A) PaCO2 will be lower than normal, pH will be higher than normal range, and HCO3- will be lower than normal
B) PaCO2 will be lower than normal, pH will be within normal range, and HCO3- will be lower than normal
C) PaCO2 and pH will be within normal limits and HCO3 will be below normal
D) PaCO2 will be lower than normal, pH will be lower than normal range, and HCO3- will be lower than normal

Question 52

What does an anion gap of 18 mEq/L indicate?

A) metabolic acidosis
B) lab error
C) respiratory acidosis
D) metabolic alkalosis

Question 53

What are the most commonly measured anions in the anion gap?

A) bicarbonate and potassium
B) sodium and chloride
C) chloride and bicarbonate
D) bicarbonate and sodium

Question 54

What is the most common cause of an elevated anion gap?

A) hypoventilation
B) hyperventilation
C) accumulation of fixed acids in the blood
D) depletion of fixed acids from the blood

Question 55

What is the normal range for the anion gap (in mEq/L)?

A) 15-18
B) 5-8
C) 18-21
D) 9-14

Question 56

What acid base abnormality would be expected in third trimester pregnancy?

A) chronic ventilatory failure
B) chronic alveolar hyperventilation
C) acute ventilatory failure
D) acute alveolar hyperventilation

Question 57

When acute alveolar hyperventilation is present, which of the following would occur?

A) PaCO2 is below normal limits, pH is above normal limits, and HCO3- is within normal limits
B) PaCO2 is below normal limits, pH is above normal, and HCO3- is above normal limits
C) PaCO2 is below normal limits and pH and HCO3- are within normal limits
D) PaCO2, pH and HCO3 are all below normal limits

Question 58

What is an alternate term for acute alveolar hyperventilation?

A) metabolic alkalosis
B) respiratory alkalosis
C) respiratory acidosis
D) metabolic acidosis

Question 59

Which of the following are causes of metabolic acidosis?
I. Diabetic ketoacidosis
II. Salicylate intoxication
III. Severe diarrhea
IV. Renal failure

A) I and III only
B) I, II, III, and IV
C) I, II and III only
D) II and III only

Question 60

What changes would you expect in acid base balance in acute metabolic acidosis?

A) pH would be below normal range and HCO3- would be normal
B) pH would be below normal and HCO3- would be above normal limits
C) pH and HCO3- would be above normal limits
D) pH and HCO3- below normal

Question 61

Which acid base abnormality is present if the base excess is calculated to be -9 mEq/L?

A) respiratory acidosis
B) respiratory alkalosis
C) metabolic acidosis
D) metabolic alkalosis

Question 62

Which acid base abnormality is present if the ABG revealed a pH of 7.63, PaCO₂ of 27 mmHg, and HCO₃- of 31 mEq/L?

A) combined metabolic and respiratory alkalosis
B) metabolic alkalosis
C) metabolic alkalosis.
D) respiratory alkalosis

Question 63

Which of the following are causes of metabolic alkalosis?
I. Hypochloremia
II. Excessive vomiting
III. Severe diarrhea
IV. Diuretic therapy

A) I, II, and III only
B) I, II, III, and IV
C) II and III only
D) I, II, and IV only

Question 64

Which acid base abnormality results from hypokalemia?

A) combined metabolic and respiratory acidosis
B) combined metabolic and respiratory alkalosis
C) metabolic alkalosis
D) metabolic acidosis

Question 65

Which acid base abnormality would likely occur in a patient with acute ventilatory failure who has a complete cardiac and respiratory arrest?

A) combined metabolic and respiratory alkalosis
B) respiratory acidosis
C) metabolic acidosis
D) combined metabolic and respiratory acidosis

Question 66

A semi-conscious patient with a severe asthma episode continues to deteriorate clinically in ER and does not respond to treatment. Which acid base abnormality would you expect to be present?

A) respiratory alkalosis
B) combined metabolic and respiratory acidosis
C) metabolic acidosis
D) respiratory acidosis

Question 67

Which acid-base abnormality would be present if the ABG revealed a pH of 7.52, PaCO2 42, and HCO3- of 30 mEq/L?

A) respiratory alkalosis
B) metabolic alkalosis
C) combined respiratory and metabolic alkalosis
D) metabolic acidosis

Question 68

What is the interpretation of the acid base status for the following ABG: pH 7.08. PaCO₂ 75 mmHg, HCO3- 20 mEq/L

A) combined metabolic and respiratory acidosis
B) acute metabolic acidosis
C) acute respiratory acidosis
D) combined metabolic and respiratory alkalosis