Effect of electrode gel application between patient’s skin and electrode belt on electrical impedance tomography of the thorax

Abstract

Electrical impedance tomography (EIT) is a non-invasive, radiation-free imaging method that can be used for bed-side monitoring of the distribution of ventilation in lungs. However, using EIT for lung monitoring in research and clinical practice is still limited by many methodical issues. In this case study, we analyzed the possible effect the application of electrode gel between the subject’s skin and the electrode belt can have on the EIT lung image. If the gel is wrongly applied, it can create a conductive connection between neighboring electrodes and distort the EIT signal. Our pilot study first minimized several unpredicted factors causing changes in EIT image and then confirmed that the conductive connection of the electrodes can lead to significant changes in the evaluated distribution of ventilation. Based on our preliminary findings, a greater study will follow with the aim of providing an official recommendation of how the gel should be applied to avoid possible errors that could lead to inaccurate conclusions about patients’ health status.