Dysfunction of the respiratory system, which supplies the body with the oxygen needed for metabolic activities in the cells and removes carbon dioxide, a product of cellular metabolism. For this purpose the right ventricle of the heart pumps venous blood, containing carbon dioxide, through the pulmonary arteries into the lung capillaries, where gaseous exchanges between the blood and air occur. The arterial or oxygenated blood is then drained through the pulmonary veins into the left atrium.