A real-time monitoring system for the cardiac and respiratory parameters using bioimpedance technique

We have implemented a bioimpedance system based on a digital signal processor (DSP) chip (ADSP-2101, from Analog Device Corp.) and a personal computer (PC) with digital and modular design approaches for monitoring respiratory and cardiac parameters. The overall system contains a digital EPROM (eraseable programmable read-only-memory) oscillator, eight independent current generators, a voltmeter with digital demodulation, an amplifier, an I/O interface, and a friendly man-machine interface through the PC. Information such as respiratory flow, respiratory rate, tidal volume, heart rate, cardiac output, stroke volume and electrocardiograph (ECG) are presented in real time on the PC's monitor.