Speckle contrast optical spectroscopy improves cuffless blood pressure estimation compared to photoplethysmography (Conference Presentation)

Speckle contrast optical spectroscopy (SCOS) allows for simultaneous monitoring of blood flow (BFi) and volume (PPG) changes within each cardiac pulse. SCOS measurements were collected from 30 subjects and the BFi and PPG pulse waveforms (PWFs) were extracted. We found that machine learning models trained on both BFi and PPG features predicted blood pressure (BP) with lower errors compared to models trained only with PPG features. In addition, 20 subjects were remeasured several weeks later. The models were trained on an individual subject’s first measurement and used to predict BP for the second measurement. With the addition of BFi information, BP estimation was significantly improved.