Non-Invasive Bioimpedance Spectroscopy Device Performing Periodic Measurements of Chest Hydration - Model Development

Bioimpedance measurement of body tissues is a non-invasive method that makes it possible to obtain a lot of information about the health of a patient with cardiac problems. A particular body part is measured by injecting a constant current signal to the object and studying the frequency response of the electrical impedance of biological tissues, which depends on the tissue composition and frequency of the applied alternating current signal. The CardioBIS device was created as part of the internal project CardioBIS - Multiparameter cardiac telemonitoring system. The CardioBIS device is a non-invasive mobile device for performing periodic measurements of chest hydration by using bioimpedance spectroscopy in the range of 5 kHz to 250 kHz, impedance cardiography and electrocardiography, with electrodes attached to the patient's body. The analog input circuits of the device ensure the registration of bioimpedance leads using eight electrodes in the form of four pairs connected in parallel. Preliminary tests have been conducted to compare bioimpedance measurements of the human body with a resistor value approximately corresponding to the human impedance at low frequencies. The observed signal waveforms confirm the adopted electronic model. The device requires further work and development.