Respiratory acidosis is primarily caused by retention of which gas?

Respiratory acidosis is primarily caused by retention of which gas?

• A. Oxygen
• B. Carbon dioxide
• C. Nitrogen
• D. Hydrogen

Answer: (B)

Respiratory acidosis happens when ventilation isn’t enough to remove the carbon dioxide the body continually makes. CO2 builds up in the blood, and CO2 reacts with water to form carbonic acid, which dissociates into hydrogen ions and bicarbonate. The extra hydrogen ions lower the blood’s pH, causing acidosis. Oxygen retention and nitrogen don’t drive this acid–base change, and hydrogen as a gas isn’t the factor here—the key cause is CO2 retention. The body can compensate over time by increasing bicarbonate, but the trigger remains elevated CO2.

Respiratory acidosis happens when ventilation isn’t enough to remove the carbon dioxide the body continually makes. CO2 builds up in the blood, and CO2 reacts with water to form carbonic acid, which dissociates into hydrogen ions and bicarbonate. The extra hydrogen ions lower the blood’s pH, causing acidosis. Oxygen retention and nitrogen don’t drive this acid–base change, and hydrogen as a gas isn’t the factor here—the key cause is CO2 retention. The body can compensate over time by increasing bicarbonate, but the trigger remains elevated CO2.