Distribution of pulmonary ventilation in the lateral decubitus position of healthy adults under Non-Invasive Mechanical Ventilation: a pilot study

Objective: In the lateral decubitus position, the largest percentage of pulmonary ventilation in non-sedated subjects is distributed mainly in the dependent lung. Methods: We aimed to investigate, via impedance tomography, the distribution of pulmonary ventilation in the lateral position under the effect of different Continuous Positive Airway Pressure (CPAP) levels (0, 5, 10 cm H2O) in healthy subjects. The volunteers were noninvasively ventilated in both lateral positions and supine positions at the beginning and end of the process. Results: A statistically significant difference between the percentage distribution of lung ventilation in different CPAP levels in the right and left lateral decubitus body positions was observed. Conclusion: We concluded that in the lateral position, as positive pressure increases, ventilation of the dependent lung increases, while, conversely, pulmonary ventilation of the non-dependent lung decreases.