Bluetooth portable device for continuous ECG and patient motion monitoring during daily life

Continuous patient monitoring during daily life can provide valuable information to different medical specialties. Indeed, long recording of related cardiac signals such as ECG, respiration and also other information such as body motion can improve diagnosis and monitor the evolution of many widespread diseases. Key-issues for portable or even wearable biomedical devices are: power consumption, longterm sensors, comfortable wearing, easy and wireless connectivity. Within this scenario, is valuable to realize prototypes making use of novel electronic technologies and common available communication technologies to assess practical use of long-term personal monitoring and foster new ways to provide healthcare services. We realized a small, battery powered, portable monitor capable to record ECG and body three-axes acceleration and continuously wireless transmit to any Bluetooth device including PDA or cellular phone. The ECG front end offers ultra-high input impedance allowing use of dry, long-lasting electrodes such conductive rubbers or novel textile electrodes that can be embedded in clothes. A small size MEMS 3-axes accelerometer was also integrated. Patient monitor incorporate a microprocessor that controls 12-bit ADC of signals at programmable sampling frequencies (e.g. 100 Hz) and drives a Bluetooth module capable to reliable transmit real-time signals within 10 m range. All circuitry can be powered by a standard mobile phone like Ni-MH 3.6V battery that can sustain more than seven day continuous functioning utilizing the Bluetooth Sniff mode to reduce TX power. At the moment we are developing dedicated software to process data and to extract concise parameters valuable for medical studies.