SpO2 probe works-Function and principle

Pulse oximetry SpO2 refers to the percentage value of blood oxygen content and blood oxygen capacity. SpO2 has been recognized as a non-invasive, fast response, safe, and reliable continuous monitoring index.

It is currently widely used in anesthesia, surgery, and PACU and ICU. According to the spectral characteristics of oxyhemoglobin (HbO2) and reduced hemoglobin (Hb) in the red and infrared light regions, it can be seen that the absorption of HbO2 and Hb is very different in the red light region (600-700nm), and the light absorption degree and light scattering of blood The degree depends greatly on the blood oxygen saturation; in the infrared spectrum (800-1000nm), the absorption difference is large. The light absorption and light scattering of blood are mainly related to the hemoglobin content. Therefore, the content of HbO2 and Hb is different. The spectra are also different, so whether the blood in the blood oxygen saturation meter blood duct is arterial blood or venous blood saturation meter can accurately reflect the bleeding oxygen saturation according to the content of HbO2 and Hb.