Portable impedance cardiography system for real-time noninvasive cardiac output measurement

A portable impedance cardiography (ICG) system has been developed. It is battery powered, small size, and in-expensive. Only one 9.6 V Ni/Cd battery is needed to operate the system for one and half hours, continuously. In addition, a digital signal processing (DSP) chip (TMS320C50, National Instrumentation Co.) is used for real-time signal processing, event detection, and stroke volume (SV) calculation. Information such as SV, cardiac output (CO), heart rate (HR) and left ventricular ejection time (LVET) are displayed on a 128*64 dot matrix LCD and updated after each heart beat. This system is also capable of storing the above information in the internal SRAM that can be transmitted to the personal computer through an RS232 interface for further analysis, after monitoring.