Changes in the ∆EELI/∆EELV
At all ventilation mode transitions a reduction in the end-expiratory volume was measured. With increasing spontaneous breathing the dorsal regions showed an increase, while the ventral regions decrease. Changing the mode of ventilation showed a very small EELV reduction, while the onset of spontaneous breathing showed a more pronounced reduction. Stopping mechanical ventilation with the onset of spontaneous breathing resulted in a significant reduction in EELV compared with the change in mode of ventilation (PCV to PSV: -37 ml [Range: -163—33 ml] vs. PSV to SB: -142 ml [Range: -384—-19 ml]; Difference: 105 ml; 95% CI 75–135; The distribution of ∆EELV in the different lung areas is shown in Fig. Exemplary representation of the EELV reduction at the different ventilation mode transitions. Orange: reduction in EELV; blue: increase in EELV; black: no change. Changing the mode of ventilation from PCV to PSV (left) shows only a small reduction of EELV which is mostly distributed in the ventral lung areas. After termination of mechanical ventilation (PSV to SB, right), the reduction is much more pronounced and distributed more evenly in both lung regions. The ventral portion decreases in favor of the dorsal by 9.9 percentage points