HeMo: Towards an inexpensive wearable peripheral blood flow monitoring device

In a previous embodiment, HeMo used a combination of electro-resistive bands and electrical impedance tomography to visualize peripheral blood flow. In this paper we present a new embodiment, which operates without the need of electrical impedance measurement. This modification simplifies the device, making it electrode-less and further reduces the power requirements. The simplified HeMo front end is assembled on a 14mm×28mm printed circuit board, requires only 1100 μA (when powered at 4.5 V) and has proven capable of measuring limb blood volume changes and arterial blood flow directly in ml during the most common peripheral vascular disease diagnostic tests. While we are still in the process of evaluating the use of HeMo in a clinical setting, we present the simplified circuit together with a set of preliminary measurements performed on a healthy volunteer to assess peripheral vascular function.