Deck 5: Oxygenation Assessments

Question 1

An increased cardiac output causes the:
1) C(a-v)O₂ to decrease.
2) SvO₂ to increase.
3) total O₂ delivery to decrease.
4) O₂ ER to increase.

A) 1
B) 2, 3
C) 3, 4
D) 1, 2

Answer 1

1, 2

Question 2

The respiratory therapist is reviewing a patient's electronic medical record to try to verify if the patient has tissue hypoxia. Which of the following laboratory values is MOST likely to correlate with tissue hypoxia?

A) Metabolic acidosis
B) Thrombocytopenia
C) Hypokalemia
D) Bilirubinemia

Answer 2

Metabolic acidosis

Question 3

A patient has a chronic respiratory disorder and vasoconstriction of her pulmonary vascular system. What is the chief control over this vasoconstriction?

A) Low PAO₂
B) Low PaO₂
C) High PaCO₂
D) High pH

Answer 3

Low PAO₂

Question 4

A patient has been exposed to carbon monoxide during a house fire. An ABG result shows a normal PaO₂. How should the patient's PaO₂ value be interpreted?

A) The PaO₂ is being falsely elevated by the carbon monoxide.
B) The PaO₂ is being falsely decreased by the carbon monoxide.
C) The PaO₂ is accurate.
D) The PaO₂ is a false measurement because the presence of carbon monoxide makes the analyzer unable to determine the PaO₂.

Question 5

Oxygen consumption:
1) increases with exercise.
2) is the amount of oxygen used by the body.
3) is inversely related to carbon dioxide production.
4) is about 250 mL/min in the resting adult.

A) 1, 2
B) 3, 4
C) 2, 4
D) 1, 2, 4

Question 6

A person's C(a-v)O₂ increases in all of the following situations EXCEPT:

A) seizures.
B) peripheral shunting.
C) hyperthermia.
D) exercise.

Question 7

A patient is mildly hypoxemic. Which of the following signs would the respiratory therapist expect to find in this patient?

A) An increase in the patient's breathing rate and heart rate
B) A decrease in systemic blood pressure
C) Cardiac dysrhythmias on an EKG
D) Anemia

Question 8

A condition that will cause anemic hypoxia is:

A) cyanide poisoning.
B) decreased cardiac output or heart failure.
C) polycythemia.
D) carbon monoxide poisoning.

Question 9

A sample of blood has been taken from a patient's pulmonary artery. What mixed venous oxygen saturation value (SvO₂) would indicate that the patient is normal?

A) 40 mm Hg
B) 95 mm Hg
C) 75%
D) 97%

Question 10

When a sample of arterial blood is analyzed for the pressure of oxygen (PaO?), the value comes from the:

A) blood plasma.
B) leukocytes.
C) hemoglobin.
D) erythrocytes.

Question 11

A condition that will cause hypoxic hypoxia is:

A) cyanosis.
B) decreased cardiac output or heart failure.
C) hypoventilation from an overdose of a sedative medication.
D) carbon monoxide poisoning.

Question 12

Polycythemia is:
1) a condition of too many red blood cells.
2) a condition of too few red blood cells.
3) caused by lack of iron in the diet.
4) the body's response to chronic hypoxemia.

A) 1, 2
B) 2, 3
C) 1, 4
D) 2, 4

Question 13

The respiratory therapist is evaluating a patient in the intensive care unit who shows signs of tissue hypoxia. Laboratory results reveal the following: HgB 14.8 grams, CaO₂ 19.6 vol. %, PaO₂ 102 mm Hg, a-v difference 9.8 vol. %, PvO₂ 24 mm Hg. Based on these results, which of the following types of hypoxia does this patient have?

A) Hypoxic hypoxia
B) Anemic hypoxia
C) Circulatory hypoxia
D) Histotoxic hypoxia