In Vitro and In Vivo Studies for a Bio-Impedance Vital-Sign Monitor

摘要

Bio-impedance can be used for peripheral pulse detection as a non- invasive method for continuous vital sign monitoring. The objective of this study was to evaluate the commercially available electrode materials that might be useful as wearable electrodes for the measurement of bio-impedance puse wave, to measure pulse variability, and test pulse detection sensitivity. Electrode down-selection was performed based on in vivo studies. A total of 13 conductive materials and 13 subjects were measured. Arm cuff inflation was used to measure pulse sensitivity. Two PCs were used for data collection. Reproducibility and sensitivity of the bio-impedance measurement were comparable to the sensitivities of the pulse oximeter, laser Doppler, and Doppler ultrasound. There was no statistical difference between the bio-impedance measurement and the other techniques. Results demonstrated that bio-impedance offers potential for use as a multifunctional, continuous, non-invasive life sign monitor for both military and civilian purposes.