Certified Transport Registered Nurse Certification Practice Exam

What percentage of CO2 is transported in plasma?

1. 20%

2. 10%

3. 30%

4. 50%

The correct answer is: 10%

The correct percentage of carbon dioxide (CO2) transported in plasma is approximately 7-10%. This includes CO2 that exists as dissolved gas in the plasma, which is a small but important component of total CO2 transport in the body. The primary modes of CO2 transport include its conversion to bicarbonate ions in red blood cells, a process that accounts for about 70% of CO2 transport. The remaining CO2 is carried bound to hemoglobin. Thus, recognizing that only a small percentage of CO2 is dissolved in the plasma helps to appreciate the overall physiology of gas exchange and transport in the bloodstream. This knowledge is critical for understanding respiratory function, as well as for monitoring patients who may have conditions affecting their CO2 levels, such as respiratory acidosis or alkalosis. Familiarity with the distribution of CO2 transport in the body is also essential in a transport nursing context, where assessments and interventions can be tailored to manage a patient's respiratory status effectively.