Biophotonics for tissue oxygenation analysis

Generally, tissue oxygenation refers to oxygen saturation that is a relative measure of the percentage of dissolved oxygen in tissue. Tissue oxygenation occurs when oxygen molecules enter the tissues of humans, such as occurs when blood is oxygenated in the lungs via oxygen molecules traveling from the air and into the blood. Blood, the body fluid responsible for transport materials and waste products, is composed of cells and plasma. More than 99% of the cells in blood are erythrocytes, which carry oxygen from and carbon dioxide to the lungs. The cardiovascular system is responsible for proper blood circulation throughout the body, and the ability of oxygen delivery plays an important role for vital sign monitoring, especially for cardiovascular insufficiency assessment for critical patients with heart failure, septic shock, and cerebral ischemia.