Journal article
Atelectrauma can be avoided if expiration is sufficiently brief: evidence from inverse modeling and oscillometry during airway pressure release ventilation
Critical care (London, England), Vol.28(1), 329
10/08/2024
DOI: 10.1186/s13054-024-05112-w
PMCID: PMC11462759
PMID: 39380082
Abstract
Background
Airway pressure release ventilation (APRV) has been shown to be protective against atelectrauma if expirations are brief. We hypothesize that this is protective because epithelial surfaces are not given enough time to come together and adhere during expiration, thereby avoiding their highly damaging forced separation during inspiration.
Methods
We investigated this hypothesis in a porcine model of ARDS induced by Tween lavage. Animals were ventilated with APRV in 4 groups based on whether inspiratory pressure was 28 or 40 cmH2O, and whether expiration was terminated when end-expiratory flow reached either 75% (a shorter expiration) or 25% (a longer expiration) of its initial peak value. A mathematical model of respiratory system mechanics that included a volume-dependent elastance term characterized by the parameter
was fit to airway pressure-flow data obtained each hour for 6 h post-Tween injury during both expiration and inspiration. We also measured respiratory system impedance between 5 and 19 Hz continuously through inspiration at the same time points from which we derived a time-course for respiratory system resistance (
).
Results
during both expiration and inspiration was significantly different between the two longer expiration versus the two shorter expiration groups (ANOVA, p < 0.001). We found that was most depressed during inspiration in the higher-pressure group receiving the longer expiration, suggesting that reflects a balance between strain stiffening of the lung parenchyma and ongoing recruitment as lung volume increases. We also found in this group that
increased progressively during the first 0.5 s of inspiration and then began to decrease again as inspiration continued, which we interpret as corresponding to the point when continuing derecruitment was reversed by progressive lung inflation.
Conclusions
These findings support the hypothesis that sufficiently short expiratory durations protect against atelectrauma because they do not give derecruitment enough time to manifest. This suggests a means for the personalized adjustment of mechanical ventilation.
Details
- Title: Subtitle
- Atelectrauma can be avoided if expiration is sufficiently brief: evidence from inverse modeling and oscillometry during airway pressure release ventilation
- Creators
- Jason H. T. Bates - University of VermontDavid W. Kaczka - University of IowaMichaela Kollisch-Singule - SUNY Upstate Medical UniversityGary F. Nieman - SUNY Upstate Medical UniversityDonald P. Gaver - Tulane University
- Resource Type
- Journal article
- Publication Details
- Critical care (London, England), Vol.28(1), 329
- DOI
- 10.1186/s13054-024-05112-w
- PMID
- 39380082
- PMCID
- PMC11462759
- NLM abbreviation
- Crit Care
- ISSN
- 1364-8535
- eISSN
- 1466-609X
- Publisher
- BioMed Central
- Grant note
The authors acknowledge the help of Nirav Daphtary, M.Sc., who constructed the oscillometry device used to make the impedance measurements reported herein.
- Language
- English
- Date published
- 10/08/2024
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Radiology; Anesthesia
- Record Identifier
- 9984722943102771
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