Deck 13: Clinical Assessment of Acid-Base and Oxygenation Status

Question 1

What is the most common clinical condition associated with respiratory acidosis?

A) Pneumonia
B) ARDS
C) Asthma
D) COPD

Answer 1

COPD

Question 2

When has full acid-base compensation occurred?

A) When PaCO₂ and HCO₃^- go in opposite directions
B) When PaCO₂ and HCO₃^- go in the same direction
C) When pH remains on the alkaline or acid side close to the normal range
D) When pH is restored to the normal range

Answer 2

When pH is restored to the normal range

Question 3

Which of the following is the most common cause of iatrogenic respiratory alkalosis?

A) Oxygen therapy
B) Pulmonary hygiene
C) Mechanical ventilation
D) Bronchodilation therapy

Answer 3

Mechanical ventilation

Question 4

What is the interpretation of a blood gas that shows a pH of 7.44, a PaCO₂ of 50 mm Hg, a PaCO₂ of 48 mm Hg, and an [HCO₃^-] of 33 mEq/L in a patient with advanced COPD?

A) Uncompensated respiratory acidosis
B) Partially compensated respiratory alkalosis
C) Compensated metabolic alkalosis
D) Acute hyperventilation superimposed on chronic respiratory acidosis

Question 5

Which of the following are effects of a rapidly rising PaCO₂?
I.Increased intracranial pressure
II.Myoclonus
III.Mental confusion
IV.Cerebral vasoconstriction

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

Question 6

Which acute level of PaCO₂ can lead to coma in patients without chronic hypercapnia?

A) >45 mm Hg
B) >55 mm Hg
C) >60 mm Hg
D) >70 mm Hg

Question 7

Which of the following is the primary disturbance associated with the following blood gas: pH is 7.36, PaCO₃ is 80 mm Hg, and HCO₃^- is 44 mEq/L?

A) Respiratory
B) Metabolic
C) Combined
D) No disturbance is present.

Question 8

What is the most common cause of hyperventilation in patients with pulmonary disease?

A) Acidosis
B) Hypercapnia
C) Hypoxemia-induced respiratory alkalosis
D) Hypercapnia not refractory to oxygen therapy

Question 9

What is the interpretation of the following blood gas reading: pH is 7.15, PaCO₂ is 80 mm Hg, and HCO₃^- is 26 mEq/L?

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

Question 10

Following a rise in PaCO₂, when is full renal compensation for respiratory acidosis expected to occur?

A) Immediately
B) In a few minutes
C) Over the next 12 hours
D) Several days

Question 11

Which of the following are causes of hypoxia-induced respiratory alkalosis?
I.High altitude
II.Asthma
III.Pneumonia
IV.Pulmonary edema

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

Question 12

When does renal compensation begin?

A) As soon as PaCO₂ rises
B) Within a few minutes after PaCO₂ rises
C) Over the next 12 hours after PaCO₂ rises
D) Several days after PaCO₂ rises

Question 13

When has partial acid-base compensation occurred?

A) When PaCO₂ and HCO₃^- go in opposite directions
B) When PaCO₂ and HCO₃- go in the same direction
C) When pH is within the normal range
D) When the noncausative component (either PaCO₂ or HCO₃^-) is also abnormal in a way that brings the pH back toward the normal range

Question 14

Which of the following are common causes of hypoventilation and respiratory acidosis?
I.Central nervous system depression
II.Extreme obesity
III.Neuromuscular disorders
IV.Pulmonary fibrosis

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

Question 15

Which of the following is an early sign of respiratory alkalosis?

A) Headache
B) Blurred vision
C) Nausea
D) Paresthesia

Question 16

Which of the following are associated with hypocapnic cerebral vasoconstriction?
I.Light-headedness
II.Dizziness
III.Tinnitus
IV.Syncope

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

Question 17

Which of the following laboratory values is typically ignored in the calculation of the anion gap?

A) Na+
B) K+
C) Cl-
D) HCO₃-

Question 18

What is the interpretation of a blood gas that shows a low PaCO₂, a low [HCO₃^-], and an alkaline pH?

A) Uncompensated respiratory acidosis
B) Partially compensated respiratory alkalosis
C) Uncompensated metabolic alkalosis
D) Partially compensated metabolic alkalosis

Question 19

What is the interpretation of the following blood gas information: pH is 7.36, PaCO₂ is 80 mm Hg, and HCO₃^- is 44 mEq/L?

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

Question 20

What is the interpretation of a blood gas that shows a high PaCO₂, a high [HCO₃^-], and an acid pH not quite in the normal range?

A) Uncompensated respiratory acidosis
B) Partially compensated respiratory acidosis
C) Uncompensated metabolic alkalosis
D) Partially compensated metabolic alkalosis

Question 21

What is the interpretation of a blood gas that shows a pH of 7.10, a PaCO₂ of 50 mm Hg, and an [HCO₃-] of 15 mEq/L?

A) Uncompensated respiratory acidosis
B) Partially compensated respiratory alkalosis
C) Compensated metabolic alkalosis
D) Combined respiratory and metabolic acidosis

Question 22

Which of the following acid-base disturbances is associated with the presence of vomiting or with continuous nasogastric suctioning?

A) Mixed metabolic and respiratory alkalosis
B) Mixed metabolic and respiratory acidosis
C) Metabolic acidosis
D) Metabolic alkalosis

Question 23

Which of the following are categories of tissue hypoxia?
I.Hypoxic
II.Anemic
III.Stagnant
IV.Histotoxic

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

Question 24

On average, how much does the PaCO₂ rise for every 1 mEq/L increase in the plasma [HCO₃-]?

A)0.2 mm Hg
B)0.5 mm Hg
C)0.7 mm Hg
D)1.0 mm Hg

Question 25

At which of the following pH levels are most serious cardiac arrhythmias less likely?

A) Below 7.3
B) Below 7.2
C) Below 7.1
D) Below 7.0

Question 26

How much should the PaO₂ rise for every 10% increase in FIO₂?

A) 40 mm Hg
B) 50 mm Hg
C) 60 mm Hg
D) 70 mm Hg

Question 27

Which of the following conditions is associated with Kussmaul's respiration?

A) Diabetic ketoacidosis
B) CO poisoning
C) Congestive heart failure
D) ARDS

Question 28

Which of the following laboratory values is used as an indicator of tissue hypoxia?

A) Glucose
B) pH
C) Tumor necrosis factor
D) Lactate

Question 29

Which of the following conditions may limit compensatory hypoventilation for metabolic alkalosis?
I.Anxiety
II.Pain
III.Infection
IV.Fever

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

Question 30

What is the tissues' resting oxygen consumption?

A) 10% of the oxygen delivered to them
B) 15% of the oxygen delivered to them
C) 20% of the oxygen delivered to them
D) 25% of the oxygen delivered to them

Question 31

Which of the following conditions makes metabolic alkalosis the most complicated acid-base imbalance to treat in acutely ill patients?

A) Hyperglycemia
B) Liver disease
C) Fluid and electrolyte imbalances
D) Hypoglycemia

Question 32

What is the normal range for the anion gap?

A) 4 to 8 mEq/L
B) 8 to 16 mEq/L
C) 16 to 24 mEq/L
D) 24 to 32 mEq/L

Question 33

If Hb and cardiac output are normal, PaO₂ must acutely decrease to which of the following levels before clinical manifestations appear?

A) 71 to 80 mm Hg
B) 61 to 70 mm Hg
C) 50 to 60 mm Hg
D) 40 to 49 mm Hg

Question 34

What will be the expected pH if the PaCO₂ is 50 mm Hg in the presence of a normal metabolic status?

A)7.0
B)7.24
C)7.30
D)7.34

Question 35

Which of the following should be the focus of evaluating oxygenation?

A) PaO₂ levels
B) PaCO₂ corresponding changes
C) Oxygen delivery to the tissues
D) FIO₂

Question 36

Which of the following therapies is considered the best treatment for carbon monoxide poisoning?

A) 100% inspired oxygen
B) 50% inspired oxygen
C) Hyperbaric oxygen
D) Positive pressure ventilation

Question 37

Which of the following therapies is considered a response to chronic hypoxemia?

A) Increased cardiac output
B) Increased perfusion
C) Tachycardia
D) Increased red blood cell production