As many as 900,000 people in the United States are affected by Deep Vein Thrombosis and Pulmonary Embolisms (DVT/PE) each year, killing 100,000 Americans annualy. DVT occurs when a blood clot forms in a deep vein as a result of blood that moves too slowly through the veins.

Current methods of identifying and treating DVT are reactive, acting in response to symptoms rather than preventing them. For this reason, we decided to develop a proactive approach in preventing DVT/PE in high risk individuals, particularly in situations where they are immobile for an extended period of time where circulation tends to slow down. By tracking a patient’s blood flow in these high risk situations, we can identify if a blood clot is imminent and alert the user to take the necessary precautionary actions.

We are using photoplethysmography, a non-invasive technique that measures the fluctuations of blood volume in a given region. It achieves this by sending light pulses into the scanned region (upper calf) and measuring the attenuation of the reflected pulse. We can then process this received signal and infer how blood is flowing. We will focus on developing the necessary hardware and software to reproduce and validate this technique in order to build a robust blood measuring device.