Which of the following statement(s) is/are true concerning carbon dioxide kinetics?

a. The amount of carbon dioxide produced is equivalent to the amount of oxygen consumed

c. Normally the amount of carbon dioxide excreted through the lung is exactly equal to the amount of carbon dioxide produced in peripheral tissues

d. The amount of carbon dioxide excreted is a function of ventilation of perfused alveoli

The total amount of carbon dioxide produced by systemic metabolism is roughly equivalent to the amount of oxygen consumed (100–120 cc/m2/min, 200 cc/min in a typical adult). CO2 production is increased or decreased by each of the factors that causes an increase or decrease in oxygen consumption. Most of the carbon dioxide in blood is present as bicarbonate ion which cannot be changed quickly. However, the metabolically produced CO2 is mostly present as dissolved carbon dioxide, added to the blood in the peripheral tissues and excreted in the lung. In a steady state, the amount of carbon dioxide excreted through the lung is exactly equal to the amount of carbon dioxide produced in peripheral tissues. The amount of carbon dioxide excreted is a function of ventilation of perfused alveoli (i.e. the alveolar ventilation/min).