Many factors can influence the amount of oxygen that moves through the alveoli, into the blood, and then to the tissue.
Common factors include the following:
- destruction of alveoli (e.g., emphysema)
- pulmonary edema
- airway blockage (e.g., asthma)
- inadequate blood supply (e.g., anemia)
- diffusion of CO2 and O2
We evaluate oxygen status by measuring pO2, pH, and pCO2 in a blood gas analysis. Oxygen is measured as the partial pressure of oxygen (pO2), or the amount of oxygen dissolved in the blood. Carbon dioxide is measured as the partial pressure of carbon dioxide (pCO2), or the amount of carbon dioxide dissolved in the blood.
