Breath holding does not lead to carbon dioxide retention, but an increase in carbon dioxide concentration can occur. Breath-holding is a short-term action that does not result in inhalation. The amount of oxygen in the body gradually decreases, and due to metabolism, the amount of carbon dioxide accumulates in the body gradually increases, but it is not carbon dioxide retention, and it is only a temporary increase. Carbon dioxide retention indicates that carbon dioxide will remain in the body for a long period of time, and is mainly seen in patients with chronic obstructive pulmonary disease (COPD). Chronic disease will lead to structural changes in the lungs of the patient, resulting in persistent ventilation dysfunction, which will lead to carbon dioxide retention. The increase in carbon dioxide caused by breath-holding will be gradually eliminated from the body with respiratory movements and gradually return to normal, which will not lead to carbon dioxide retention.