Signal waveform agreement between spirometer and impedance pneumography of six chest band electrode configurations

Abstract

There is currently no approved clinical method for monitoring of pulmonary flow and volume without highly obtrusive instrumentation like a mask. Impedance pneumography (IP) seems to be the most promising method to establish accurate Holter type breathing measurement. We measured IP and spirometer volume signal from 14 subjects in static conditions from six different tetrapolar electrode configurations using a chest band with textile silver electrodes. We compared the continuous waveforms from spirometer and IP with Pearson linear correlation coefficients ρ and found clear differences between the six configurations. For the best configuration the difference between the impedance and spirometer signals at ρ> 0.98 was almost insignificant for all subjects. In these static conditions the IP method was found to be both comfortable and accurate for continuous lung volume measurement.