Electrical impedance tomography: potentials and pitfalls

Purpose of reviewElectrical impedance tomography (EIT) is a useful noninvasive tool for monitoring ventilation finding its way into the clinical setting. The focus of this review is to discuss the balance between the potential for EIT as a clinical monitor accepting a level of uncertainty and the scientific demand for absolute perfection. Recent findingsThe controversy concerning whether EIT impedance changes can be safely used to monitor lung volume changes now appears to be solved after recent elegant studies. It is now high time to display lung volume changes measured by EIT in clinical units, that is in millilitres following calibration versus tidal volume. A growing number of indices for regional ventilation distribution are emerging some of which should be further evaluated and developed for clinical decision support. SummaryAlready now EIT is a useful clinical monitor. Still more work is needed to develop and interpret indices which are simple enough to be used in the clinical setting to guide the clinician towards effective and safe ventilator management.

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