Optical sensor system for non-invasive blood diagnosis

In the perioperative area, the period before and after surgery, it is essential to measure diagnostic parameters such as oxygen saturation, hemoglobin (Hb) concentration and pulse. The Hb concentration in human blood is an important parameter to evaluate the physiological condition. By determining the Hb concentration it is possible to observe imminent postoperative bleeding and autologous retransfusions. Currently, invasive methods are used to measure the Hb concentration. For this purpose blood is taken and analyzed. The disadvantage of this method is the delay between the blood collection and its analysis, which doesn´t permit a real-time patient monitoring in critical situations. A non-invasive method allows pain free online patient monitoring with minimum risk of infection and facilitates real time data monitoring allowing immediate clinical reaction to the measured data.