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Updated: Jun 22, 2026

Monitoring Lung Function with Electrical Impedance Tomography in the Intensive Care Unit
Published on: September 6, 2024
Is proportional-assist ventilation with load-adjustable gain factors a user-friendly mode?
Nectaria Xirouchaki1, Eumorfia Kondili, Maria Klimathianaki
1Department of Intensive Care Medicine, University Hospital of Heraklion, Medical School, University of Crete, Heraklion, Crete, Greece.
Objectives:
The aim of this study was to compare the number of interventions (ventilator settings and sedatives, analgesics and vasoactive medication dose manipulations) between critically ill patients on proportional-assist ventilation with load-adjustable gain factors (PAV+) and those on pressure support (PS).
Design:
Retrospective analysis of data from a previous randomized clinical trial.
Methods:
A total of 208 patients who were mechanically ventilated on controlled modes and met criteria for assisted breathing were randomized to receive either PS (n = 100) or PAV+ (n = 108). Changes in ventilator settings and in the dose of sedatives, analgesics, and vasoactive medications were identified during the period in which the patients were ventilated either with PS (30.4 +/- 17.4 h) or PAV+ (30.0 +/- 18.1 h) and classified as changes to facilitate weaning (CFW) or changes to respond to deterioration (CD).
Results:
The mean number of changes in ventilator settings was significantly higher with PS than that with PAV+ (10.7 +/- 5.7 vs. 8.9 +/- 4.6). With PS the proportion of these changes classified as CFW was significantly lower than that with PAV+ (59.8% vs. 69.2%). Dyssynchrony as a cause of CD was more likely to occur with PS than with PAV+ (42 vs. 3%). The mean number of changes in the dose of sedatives, analgesics, and vasoactive medications was higher with PS than with PAV+, the difference being significant only for sedatives (4.06 +/- 3.8 vs. 2.82 +/- 3.4).
Conclusions:
Compared to PS, PAV+ is associated with fewer intervention in terms of ventilator settings and sedative dose changes.
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