Oxygen

Oxygen is an essential element for living organisms. It is involved in cellular metabolism and catabolism and permits production of energy in the form of adenosine triphosphate (ATP). The variation of the partial pressure of oxygen in the blood affects the cardiovascular system, the respiratory system, cellular metabolism, and the central nervous system. Deprivation of oxygen, resulting in tissue hypoxia, results in a rapid deterioration of myocardial and central nervous activity. Intervention with oxygen therapy is essential for the resolution of adequate tissue oxygenatio

Oxygen administered by inhalation is absorbed by alveolar-capillary exchange. It is present in the plasma in the solution and is transported by erythrocytes in the form of oxyhaemoglobin. Oxygen released at tissue level by oxyhaemoglobin is then used in mitochondria for the synthesis of ATP. Following these catalytic reactions it reappears in the form of CO2 and H2O. Both metabolised and excess, unmetabolised oxygen are eliminated from the body during exhalation.