Electrical Impedance tomography for lung recruitment monitoring—technical aspects of clinical usage and interpretation

In clinical routine, computed tomography (CT) is considered as the gold standard for evaluation of lung recruitment and lung aeration inhomogeneity. Nevertheless, CT has disadvantages that should be taken into account, including a high dose of ionizing radiation, inaccessibility of CT bedside and impossibility of its continuous usage. Electrical impedance tomography (EIT) does not have these disadvantages; therefore, EIT might be a suitable alternative to CT for the lung monitoring. The term “tomography” in “EIT” evokes that it is primarily an imaging technique; however, due to the physical principle, EIT can never reach as high spatial resolution and tissue contrast as CT. Therefore, EIT data should be processed in an index-like manner rather than evaluated as an image. Due to the complex analysis, the data processing is sensitive to errors and misinterpretation. The aim of the study is to show how EIT can be used for lung recruitment evaluation and to show possible sources of errors during the EIT data processing.