An Adjusted Method of Photoplethysmography Detection in Poor Perfusion

Photoplethysmography (PPG) is an effective technique that can be used to detect blood volume changes in the microvascular bed of tissue. However, when the patients are in poor perfusion, the signal of PPG will be too weak to detect. So a dynamic variable amount of light detection method is designed to solve the problem. The method adjusts the hardware and software of original method. By using this method, the detector can detect the waveform of PPG more effectively, and greatly improve the accuracy of measurement. It has been used in clinical studies of surgical anesthesia, and achieved very good results.