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Updated: Jan 7, 2026
Monitoring Lung Function with Electrical Impedance Tomography in the Intensive Care Unit
Published on: September 6, 2024
Effects of Five Body Positions on the Regional Ventilation Distribution Assessed Using Electrical Impedance
Natalia Morales Mestre1,2,3, Guillaume Maerckx1,2, Xavier Wittebole2
1Dr. Morales Mestre, Dr. Reychler, and Mr. Maerckx are affiliated with Secteur de Kinésithérapie et Ergothérapie, Cliniques universitaires Saint-Luc, Brussels, Belgium.
Background:
Electrical impedance tomography (EIT) is a noninvasive method for visualization and quantification of regional ventilation. The objective of this study was to assess regional variations in ventilation across different positions in healthy subjects.
Methods:
Regional differences in ventilation were compared between the right and left lateral decubitus positions, as well as between the supine, semi-sitting, and prone positions. EIT was performed using a PulmoVista 500 (Dräger Medical, Lübeck, Germany).
Results:
During lateral decubitus, ventilation significantly increased in the dependent lung. In the right lung, ventilation was 42.5 ± 11.4% in the left lateral decubitus compared with 65.2 ± 12.8% in the right lateral decubitus (P < .001). In the left lung, ventilation was 56.6 ± 11.6% in left lateral decubitus versus 34.4 ± 13.0% in right lateral decubitus (P < .001). These changes were mainly observed in the ventral dependent quadrants. In the supine, semi-sitting, and prone positions, no global differences in ventilation distribution were observed. However, ventilation slightly increased in the left ventral quadrant (supine < prone, P = .03) and decreased in the right dorsal quadrant (supine > prone, P = .03). These subtle variations likely reflect the physiological characteristics of healthy individuals.
Conclusions:
EIT demonstrated a clear redistribution of ventilation toward the dependent lung in lateral decubitus positions. In contrast, only minimal regional ventilation changes were observed among supine, semi-sitting, and prone positions in healthy subjects. These findings support the utility of EIT in assessing position-related ventilation shifts and underscore the need for further research in patients with impaired pulmonary function.
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