Progressive Care Nursing Certification (PCCN) Practice Exam

What factors determine the amount of oxygen delivered to the tissues?

1. cardiac output

2. hemoglobin levels

3. oxygen saturation

4. all of the above

The correct answer is: all of the above

The amount of oxygen delivered to the tissues is a result of multiple interconnected factors, making the choice of all the responses pertinent. Cardiac output is crucial because it represents the volume of blood the heart pumps per minute. Higher cardiac output means more blood, and consequently more oxygen, is delivered to the tissues. Hemoglobin levels play a vital role as well, since hemoglobin is responsible for transporting oxygen from the lungs to the rest of the body. Adequate hemoglobin levels are necessary to bind and carry sufficient amounts of oxygen. Oxygen saturation, which indicates the percentage of hemoglobin that is saturated with oxygen, is another important determinant. If the saturation is low, even if there is adequate hemoglobin and cardiac output, the tissues may still not receive enough oxygen. Thus, these three factors—cardiac output, hemoglobin levels, and oxygen saturation—work together to regulate oxygen delivery to the tissues, highlighting why all of these components are significant in measuring and understanding oxygen transport in the body.