Logo image
Back
Dynamic lung aeration and strain with positive end-expiratory pressure individualized to maximal compliance versus ARDSNet low-stretch strategy: a study in a surfactant depletion model of lung injury
Journal article   Open access   Peer reviewed

Dynamic lung aeration and strain with positive end-expiratory pressure individualized to maximal compliance versus ARDSNet low-stretch strategy: a study in a surfactant depletion model of lung injury

Congli Zeng, Min Zhu, Gabriel Motta-Ribeiro, David Lagier, Takuga Hinoshita, Mingyang Zang, Kira Grogg, Tilo Winkler and Marcos F. Vidal Melo
Critical care (London, England), Vol.27(1), pp.307-17
08/03/2023
DOI: 10.1186/s13054-023-04591-7
PMCID: PMC10401825
PMID: 37537654
url
https://doi.org/10.1186/s13054-023-04591-7View
Published (Version of record) Open Access

Abstract

Background Positive end-expiratory pressure (PEEP) individualized to a maximal respiratory system compliance directly implies minimal driving pressures with potential outcome benefits, yet, raises concerns on static and dynamic overinflation, strain and cyclic recruitment. Detailed accurate assessment and understanding of these has been hampered by methodological limitations. We aimed to investigate the effects of a maximal compliance- guided PEEP strategy on dynamic lung aeration, strain and tidal recruitment using current four-dimensional computed tomography (CT) techniques and analytical methods of tissue deformation in a surfactant depletion experimental model of acute respiratory distress syndrome (ARDS). Methods ARDS was induced by saline lung lavage in anesthetized and mechanically ventilated healthy sheep (n = 6). Animals were ventilated in a random sequence with: (1) ARDSNet low-stretch protocol; (2) maximal compliance PEEP strategy. Lung aeration, strain and tidal recruitment were acquired with whole-lung respiratory-gated high-resolution CT and quantified using registration-based techniques. Results Relative to the ARDSNet low-stretch protocol, the maximal compliance PEEP strategy resulted in: (1) improved dynamic whole-lung aeration at end-expiration (0.456 +/- 0.064 vs. 0.377 +/- 0.101, P = 0.019) and end-inspiration (0.514 +/- 0.079 vs. 0.446 +/- 0.083, P = 0.012) with reduced non-aerated and increased normally-aerated lung mass without associated hyperinflation; (2) decreased aeration heterogeneity at end-expiration (coefficient of variation: 0.498 +/- 0.078 vs. 0.711 +/- 0.207, P = 0.025) and end-inspiration (0.419 +/- 0.135 vs. 0.580 +/- 0.108, P = 0.014) with higher aeration in dorsal regions; (3) tidal aeration with larger inspiratory increases in normally-aerated and decreases in poorly-aerated areas, and negligible in hyperinflated lung (Aeration x Strategy: P = 0.026); (4) reduced tidal strains in lung regions with normal-aeration (Aeration x Strategy: P = 0.047) and improved regional distributions with lower tidal strains in middle and ventral lung (Region-of-interest [ROI] x Strategy: P < 0.001); and (5) less tidal recruitment in middle and dorsal lung (ROI x Strategy: P = 0.044) directly related to whole-lung tidal strain (r = 0.751, P = 0.007). Conclusions In well-recruitable ARDS models, a maximal compliance PEEP strategy improved end-expiratory/inspiratory whole-lung aeration and its homogeneity without overinflation. It further reduced dynamic strain in middleventral regions and tidal recruitment in middle-dorsal areas. These findings suggest the maximal compliance strategy minimizing whole-lung dynamically quantified mechanisms of ventilator-induced lung injury with less cyclic recruitment and no additional overinflation in large heterogeneously expanded and recruitable lungs.
 Critical Care Medicine General & Internal Medicine Life Sciences & Biomedicine Science & Technology

Details

Metrics

5 Record Views
Logo image