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Lagier D, Zeng C, Kaczka DW, Zhu M, Grogg K, Gerard SE, Reinhardt JM, Ribeiro GCM, Rashid A, Winkler T, Vidal Melo MF. Mechanical ventilation guided by driving pressure optimizes local pulmonary biomechanics in an ovine model. Sci Transl Med 2024; 16:eado1097. [PMID: 39141699 DOI: 10.1126/scitranslmed.ado1097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 05/13/2024] [Accepted: 07/24/2024] [Indexed: 08/16/2024]
Abstract
Mechanical ventilation exposes the lung to injurious stresses and strains that can negatively affect clinical outcomes in acute respiratory distress syndrome or cause pulmonary complications after general anesthesia. Excess global lung strain, estimated as increased respiratory system driving pressure, is associated with mortality related to mechanical ventilation. The role of small-dimension biomechanical factors underlying this association and their spatial heterogeneity within the lung are currently unknown. Using four-dimensional computed tomography with a voxel resolution of 2.4 cubic millimeters and a multiresolution convolutional neural network for whole-lung image segmentation, we dynamically measured voxel-wise lung inflation and tidal parenchymal strains. Healthy or injured ovine lungs were evaluated as the mechanical ventilation positive end-expiratory pressure (PEEP) was titrated from 20 to 2 centimeters of water. The PEEP of minimal driving pressure (PEEPDP) optimized local lung biomechanics. We observed a greater rate of change in nonaerated lung mass with respect to PEEP below PEEPDP compared with PEEP values above this threshold. PEEPDP similarly characterized a breaking point in the relationships between PEEP and SD of local tidal parenchymal strain, the 95th percentile of local strains, and the magnitude of tidal overdistension. These findings advance the understanding of lung collapse, tidal overdistension, and strain heterogeneity as local triggers of ventilator-induced lung injury in large-animal lungs similar to those of humans and could inform the clinical management of mechanical ventilation to improve local lung biomechanics.
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Affiliation(s)
- David Lagier
- Experimental Interventional Imaging Laboratory (LIIE), European Center for Research in Medical Imaging (CERIMED), Aix Marseille University, Marseille 13005, France
- Department of Anesthesia and Critical Care, University Hospital La Timone, APHM, Marseille 13005, France
| | - Congli Zeng
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York City, NY 10032, USA
| | - David W Kaczka
- Departments of Anesthesia and Radiology, University of Iowa, Iowa City, IA 52242, USA
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA 52242, USA
| | - Min Zhu
- Guizhou University South Campus, Guiyang City 550025, China
| | - Kira Grogg
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT 06520, USA
| | - Sarah E Gerard
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA 52242, USA
| | - Joseph M Reinhardt
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA 52242, USA
| | - Gabriel C Motta Ribeiro
- Biomedical Engineering Program, Alberto Luiz Coimbra Institute for Graduate Studies and Research in Engineering, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-594, Brazil
| | - Azman Rashid
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Tilo Winkler
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Marcos F Vidal Melo
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York City, NY 10032, USA
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2
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Fazla B, Erken O, Izbassarov D, Romanò F, Grotberg JB, Muradoglu M. Effects of Kinematic Hardening of Mucus Polymers in an Airway Closure Model. JOURNAL OF NON-NEWTONIAN FLUID MECHANICS 2024; 330:105281. [PMID: 39036645 PMCID: PMC11258864 DOI: 10.1016/j.jnnfm.2024.105281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
The formation of a liquid plug inside a human airway, known as airway closure, is computationally studied by considering the elastoviscoplastic (EVP) properties of the pulmonary mucus covering the airway walls for a range of liquid film thicknesses and Laplace numbers. The airway is modeled as a rigid tube lined with a single layer of an EVP liquid. The Saramito-Herschel-Bulkley (Saramito-HB) model is coupled with an Isotropic Kinematic Hardening model (Saramito-HB-IKH) to allow energy dissipation at low strain rates. The rheological model is fitted to the experimental data under healthy and cystic fibrosis (CF) conditions. Yielded/unyielded regions and stresses on the airway wall are examined throughout the closure process. Yielding is found to begin near the closure in the Saramito-HB model, whereas it occurs noticeably earlier in the Saramito-HB-IKH model. The kinematic hardening is seen to have a notable effect on the closure time, especially for the CF case, with the effect being more pronounced at low Laplace numbers and initial film thicknesses. Finally, standalone effects of rheological properties on wall stresses are examined considering their physiological values as baseline.
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Affiliation(s)
- Bartu Fazla
- Department of Mechanical Engineering, Koc University, Istanbul, 34450, Turkey
| | - Oguzhan Erken
- School of Engineering, Institute for Infrastructure and Environment, The University of Edinburgh, Edinburgh, United Kingdom
| | - Daulet Izbassarov
- Finnish Meteorological Institute, Erik Palmenin aukio 1, Helsinki, 00560, Finland
| | - Francesco Romanò
- Univ. Lille, CNRS, ONERA, Arts et Métiers Institute of Technology, Lille, France
| | - James B. Grotberg
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, 48109, MI, USA
| | - Metin Muradoglu
- Department of Mechanical Engineering, Koc University, Istanbul, 34450, Turkey
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3
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Dayeen FR, Brandner BA, Bu W, Hall SB, Gidalevitz D. Structural determinants of collapse by a monomolecular mimic of pulmonary surfactant at the physiological temperature. SOFT MATTER 2024; 20:5745-5753. [PMID: 38982765 DOI: 10.1039/d4sm00481g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
Pulmonary surfactant forms a thin film on the liquid that lines the alveolar air-sacks. When compressed by the decreasing alveolar surface area during exhalation, the films avoid collapse from the air/water interface and reduce surface tension to exceptionally low levels. To define better the structure of compressed films that determines their susceptibility to collapse, we measured how cholesterol affects the structure and collapse of dipalmitoyl phosphatidylcholine (DPPC) monolayers at physiological temperatures. Grazing incidence X-ray diffraction (GIXD) and grazing incidence X-ray off-specular scattering (GIXOS) established the lateral and transverse structures of films on a Langmuir trough at a surface pressure of 45 mN m-1, just below the equilibrium spreading pressure at which collapse begins. Experiments with captive bubbles at a surface pressure of 51 mN m-1 measured how the steroid affects isobaric collapse. Mol fractions of the steroid (Xchol) at 0.05 removed the tilt by the acyl chains of DPPC, shifted the unit cell from centered rectangular to hexagonal, and dramatically decreased the long-range order. Higher Xchol produced no further change in diffraction, suggesting that cholesterol partitions into a coexisting disordered phase. Cholesterol had minimal effect on rates of collapse until Xchol reached 0.20. Our results demonstrate that the decreased coherence length, indicating conversion of positional order to short-range, is insufficient to make a condensed monolayer susceptible to collapse. Our findings suggest a two-step process by which cholesterol induces disorder. The steroid would first convert the film with crystalline chains to a hexatic phase before generating a fully disordered structure that is susceptible to collapse. These results lead to far-reaching consequences for formulation of animal-derived therapeutic surfactants. Our results suggest that removal of cholesterol from these preparations should be unnecessary below Xchol = 0.20.
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Affiliation(s)
- Fazle R Dayeen
- Department of Physics, Center for Molecular Study of Condensed Soft Matter (μCoSM), Illinois Institute of Technology, Chicago, IL 60616, USA.
| | - Bret A Brandner
- Pulmonary & Critical Care Medicine, Oregon Health & Science University (OHSU), Portland, OR 97239-3098, USA.
| | - Wei Bu
- NSF's ChemMatCARS, Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
| | - Stephen B Hall
- Pulmonary & Critical Care Medicine, Oregon Health & Science University (OHSU), Portland, OR 97239-3098, USA.
| | - David Gidalevitz
- Department of Physics, Center for Molecular Study of Condensed Soft Matter (μCoSM), Illinois Institute of Technology, Chicago, IL 60616, USA.
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4
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Gao W, Kanagarajah KR, Graham E, Soon K, Veres T, Moraes TJ, Bear CE, Veldhuizen RA, Wong AP, Günther A. Collagen Tubular Airway-on-Chip for Extended Epithelial Culture and Investigation of Ventilation Dynamics. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2309270. [PMID: 38431940 DOI: 10.1002/smll.202309270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 02/07/2024] [Indexed: 03/05/2024]
Abstract
The lower respiratory tract is a hierarchical network of compliant tubular structures that are made from extracellular matrix proteins with a wall lined by an epithelium. While microfluidic airway-on-a-chip models incorporate the effects of shear and stretch on the epithelium, week-long air-liquid-interface culture at physiological shear stresses, the circular cross-section, and compliance of native airway walls have yet to be recapitulated. To overcome these limitations, a collagen tube-based airway model is presented. The lumen is lined with a confluent epithelium during two-week continuous perfusion with warm, humid air while presenting culture medium from the outside and compensating for evaporation. The model recapitulates human small airways in extracellular matrix composition and mechanical microenvironment, allowing for the first time dynamic studies of elastocapillary phenomena associated with regular breathing and mechanical ventilation, as well as their impacts on the epithelium. A case study reveales increasing damage to the epithelium during repetitive collapse and reopening cycles as opposed to overdistension, suggesting expiratory flow resistance to reduce atelectasis. The model is expected to promote systematic comparisons between different clinically used ventilation strategies and, more broadly, to enhance human organ-on-a-chip platforms for a variety of tubular tissues.
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Affiliation(s)
- Wuyang Gao
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada
| | - Kayshani R Kanagarajah
- Program in Developmental & Stem Cell Biology, The Hospital for Sick Children, 686 Bay Street, PGCRL Research Tower, Toronto, Ontario, M5G 0A4, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Emma Graham
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond St, London, Ontario, N6A 3K7, Canada
- Lawson Health Research Institute, London Health Sciences Centre, 750 Base Line Rd E, London, Ontario, N6C 2R5, Canada
| | - Kayla Soon
- National Research Council Canada, 75 Bd de Mortagne, Boucherville, Quebec, J4B 6Y4, Canada
| | - Teodor Veres
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada
- National Research Council Canada, 75 Bd de Mortagne, Boucherville, Quebec, J4B 6Y4, Canada
| | - Theo J Moraes
- Department of Paediatrics, University of Toronto, 555 University Avenue, Toronto, Ontario, M5G 1×8, Canada
| | - Christine E Bear
- Program in Molecular Medicine, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1 × 8, Canada
- Department of Physiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
- Department of Biochemistry, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Ruud A Veldhuizen
- Department of Physiology and Pharmacology, University of Western Ontario, 1151 Richmond St, London, Ontario, N6A 3K7, Canada
- Lawson Health Research Institute, London Health Sciences Centre, 750 Base Line Rd E, London, Ontario, N6C 2R5, Canada
- Department of Medicine, University of Western Ontario, 1151 Richmond Street, London, Ontario, N6A 5C1, Canada
| | - Amy P Wong
- Program in Developmental & Stem Cell Biology, The Hospital for Sick Children, 686 Bay Street, PGCRL Research Tower, Toronto, Ontario, M5G 0A4, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Axel Günther
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada
- Institute of Biomedical Engineering, University of Toronto, 164 College Street, Toronto, Ontario, M5S 3G9, Canada
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5
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Zimmermann R, Roeder F, Ruppert C, Smith BJ, Knudsen L. Low-volume ventilation of preinjured lungs degrades lung function via stress concentration and progressive alveolar collapse. Am J Physiol Lung Cell Mol Physiol 2024; 327:L19-L39. [PMID: 38712429 DOI: 10.1152/ajplung.00323.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 03/27/2024] [Accepted: 04/22/2024] [Indexed: 05/08/2024] Open
Abstract
Mechanical ventilation can cause ventilation-induced lung injury (VILI). The concept of stress concentrations suggests that surfactant dysfunction-induced microatelectases might impose injurious stresses on adjacent, open alveoli and function as germinal centers for injury propagation. The aim of the present study was to quantify the histopathological pattern of VILI progression and to test the hypothesis that injury progresses at the interface between microatelectases and ventilated lung parenchyma during low-positive end-expiratory pressure (PEEP) ventilation. Bleomycin was used to induce lung injury with microatelectases in rats. Lungs were then mechanically ventilated for up to 6 h at PEEP = 1 cmH2O and compared with bleomycin-treated group ventilated protectively with PEEP = 5 cmH2O to minimize microatelectases. Lung mechanics were measured during ventilation. Afterward, lungs were fixed at end-inspiration or end-expiration for design-based stereology. Before VILI, bleomycin challenge reduced the number of open alveoli [N(alvair,par)] by 29%. No differences between end-inspiration and end-expiration were observed. Collapsed alveoli clustered in areas with a radius of up to 56 µm. After PEEP = 5 cmH2O ventilation for 6 h, N(alvair,par) remained stable while PEEP = 1 cmH2O ventilation led to an additional loss of aerated alveoli by 26%, mainly due to collapse, with a small fraction partly edema filled. Alveolar loss strongly correlated to worsening of tissue elastance, quasistatic compliance, and inspiratory capacity. The radius of areas of collapsed alveoli increased to 94 µm, suggesting growth of the microatelectases. These data provide evidence that alveoli become unstable in neighborhood of microatelectases, which most likely occurs due to stress concentration-induced local vascular leak and surfactant dysfunction.NEW & NOTEWORTHY Low-volume mechanical ventilation in the presence of high surface tension-induced microatelectases leads to the degradation of lung mechanical function via the progressive loss of alveoli. Microatelectases grow at the interfaces of collapsed and open alveoli. Here, stress concentrations might cause injury and alveolar instability. Accumulation of small amounts of alveolar edema can be found in a fraction of partly collapsed alveoli but, in this model, alveolar flooding is not a major driver for degradation of lung mechanics.
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Affiliation(s)
- Richard Zimmermann
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Franziska Roeder
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Clemens Ruppert
- Department of Internal Medicine, Justus-Liebig-University Giessen, Giessen, Germany
- University of Giessen and Marburg Lung Center (UGMLC), member of the German Center for Lung Research (DZL), Giessen, Germany
| | - Bradford J Smith
- Department of Bioengineering, College of Engineering, Design & Computing, University of Colorado Denver | Anschutz Medical Campus, Aurora, Colorado, United States
- Section of Pulmonary and Sleep Medicine, Department of Pediatrics, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado, United States
| | - Lars Knudsen
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover Medical School, Hannover, Germany
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6
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Hall SB, Zuo YY. The biophysical function of pulmonary surfactant. Biophys J 2024; 123:1519-1530. [PMID: 38664968 PMCID: PMC11213971 DOI: 10.1016/j.bpj.2024.04.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 04/08/2024] [Accepted: 04/22/2024] [Indexed: 05/12/2024] Open
Abstract
The type II pneumocytes of the lungs secrete a mixture of lipids and proteins that together acts as a surfactant. The material forms a thin film on the surface of the liquid layer that lines the alveolar air sacks. When compressed by the decreasing alveolar surface area during exhalation, the films reduce surface tension to exceptionally low levels. Pulmonary surfactant is essential for preserving the integrity of the barrier between alveolar air and capillary blood during normal breathing. This review focuses on the major biophysical processes by which endogenous pulmonary surfactant achieves its function and the mechanisms involved in those processes. Vesicles of pulmonary surfactant adsorb rapidly from the alveolar liquid to form the interfacial film. Interfacial insertion, which requires the hydrophobic surfactant protein SP-B, proceeds by a process analogous to the fusion of two vesicles. When compressed, the adsorbed film desorbs slowly. Constituents remain at the surface at high interfacial concentrations that reduce surface tensions well below equilibrium levels. We review the models proposed to explain how pulmonary surfactant achieves both the rapid adsorption and slow desorption characteristic of a functional film.
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Affiliation(s)
- Stephen B Hall
- Pulmonary and Critical Care Medicine, Oregon Health & Science University, Portland, Oregon.
| | - Yi Y Zuo
- Department of Mechanical Engineering, University of Hawaii at Manoa, Honolulu, Hawaii
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7
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Bates JHT, Kaczka DW, Kollisch-Singule M, Nieman GF, Gaver DP. Mechanical Power and Ventilator-induced Lung Injury: What Does Physics Have to Say? Am J Respir Crit Care Med 2024; 209:787-788. [PMID: 37729623 PMCID: PMC10995572 DOI: 10.1164/rccm.202307-1292vp] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/20/2023] [Indexed: 09/22/2023] Open
Affiliation(s)
| | - David W. Kaczka
- Department of Anesthesia, Department of Radiology, and Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa
| | | | - Gary F. Nieman
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York; and
| | - Donald P. Gaver
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
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8
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Geitner CM, Köglmeier LJ, Frerichs I, Langguth P, Lindner M, Schädler D, Weiler N, Becher T, Wall WA. Pressure- and time-dependent alveolar recruitment/derecruitment in a spatially resolved patient-specific computational model for injured human lungs. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2024; 40:e3787. [PMID: 38037251 DOI: 10.1002/cnm.3787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 08/28/2023] [Accepted: 10/16/2023] [Indexed: 12/02/2023]
Abstract
We present a novel computational model for the dynamics of alveolar recruitment/derecruitment (RD), which reproduces the underlying characteristics typically observed in injured lungs. The basic idea is a pressure- and time-dependent variation of the stress-free reference volume in reduced dimensional viscoelastic elements representing the acinar tissue. We choose a variable reference volume triggered by critical opening and closing pressures in a time-dependent manner from a straightforward mechanical point of view. In the case of (partially and progressively) collapsing alveolar structures, the volume available for expansion during breathing reduces and vice versa, eventually enabling consideration of alveolar collapse and reopening in our model. We further introduce a method for patient-specific determination of the underlying critical parameters of the new alveolar RD dynamics when integrated into the tissue elements, referred to as terminal units, of a spatially resolved physics-based lung model that simulates the human respiratory system in an anatomically correct manner. Relevant patient-specific parameters of the terminal units are herein determined based on medical image data and the macromechanical behavior of the lung during artificial ventilation. We test the whole modeling approach for a real-life scenario by applying it to the clinical data of a mechanically ventilated patient. The generated lung model is capable of reproducing clinical measurements such as tidal volume and pleural pressure during various ventilation maneuvers. We conclude that this new model is an important step toward personalized treatment of ARDS patients by considering potentially harmful mechanisms-such as cyclic RD and overdistension-and might help in the development of relevant protective ventilation strategies to reduce ventilator-induced lung injury (VILI).
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Affiliation(s)
- Carolin M Geitner
- Institute for Computational Mechanics, Department of Engineering Physics & Computation, TUM School of Engineering and Design, Technical University of Munich, Garching b. Muenchen, Germany
| | - Lea J Köglmeier
- Institute for Computational Mechanics, Department of Engineering Physics & Computation, TUM School of Engineering and Design, Technical University of Munich, Garching b. Muenchen, Germany
| | - Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Patrick Langguth
- Department of Radiology and Neuroradiology, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Matthias Lindner
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Dirk Schädler
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Norbert Weiler
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Tobias Becher
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Wolfgang A Wall
- Institute for Computational Mechanics, Department of Engineering Physics & Computation, TUM School of Engineering and Design, Technical University of Munich, Garching b. Muenchen, Germany
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9
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Ma H, Fujioka H, Halpern D, Bates JHT, Gaver DP. Full-lung simulations of mechanically ventilated lungs incorporating recruitment/derecruitment dynamics. FRONTIERS IN NETWORK PHYSIOLOGY 2023; 3:1257710. [PMID: 38020240 PMCID: PMC10654632 DOI: 10.3389/fnetp.2023.1257710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023]
Abstract
This study developed and investigated a comprehensive multiscale computational model of a mechanically ventilated ARDS lung to elucidate the underlying mechanisms contributing to the development or prevention of VILI. This model is built upon a healthy lung model that incorporates realistic airway and alveolar geometry, tissue distensibility, and surfactant dynamics. Key features of the ARDS model include recruitment and derecruitment (RD) dynamics, alveolar tissue viscoelasticity, and surfactant deficiency. This model successfully reproduces realistic pressure-volume (PV) behavior, dynamic surface tension, and time-dependent descriptions of RD events as a function of the ventilation scenario. Simulations of Time-Controlled Adaptive Ventilation (TCAV) modes, with short and long durations of exhalation (T Low - and T Low +, respectively), reveal a higher incidence of RD for T Low + despite reduced surface tensions due to interfacial compression. This finding aligns with experimental evidence emphasizing the critical role of timing in protective ventilation strategies. Quantitative analysis of energy dissipation indicates that while alveolar recruitment contributes only a small fraction of total energy dissipation, its spatial concentration and brief duration may significantly contribute to VILI progression due to its focal nature and higher intensity. Leveraging the computational framework, the model may be extended to facilitate the development of personalized protective ventilation strategies to enhance patient outcomes. As such, this computational modeling approach offers valuable insights into the complex dynamics of VILI that may guide the optimization of ventilation strategies in ARDS management.
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Affiliation(s)
- Haoran Ma
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, United States
| | - Hideki Fujioka
- Center for Computational Science, Tulane University, New Orleans, LA, United States
| | - David Halpern
- Department of Mathematics, University of Alabama, Tuscaloosa, AL, United States
| | - Jason H. T. Bates
- Larner College of Medicine, University of Vermont, Burlington, VT, United States
| | - Donald P. Gaver
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, United States
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10
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Tonelli R, Grasso S, Cortegiani A, Ball L, Castaniere I, Tabbì L, Fantini R, Andrisani D, Gozzi F, Moretti A, Bruzzi G, Manicardi L, Cerri S, Samarelli AV, Raineri G, Murgolo F, Carzoli A, Di Mussi R, Busani S, Rizzoni R, Grasselli G, Clini E, Marchioni A. Physiological effects of lung-protective ventilation in patients with lung fibrosis and usual interstitial pneumonia pattern versus primary ARDS: a matched-control study. Crit Care 2023; 27:398. [PMID: 37853480 PMCID: PMC10585808 DOI: 10.1186/s13054-023-04682-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 10/07/2023] [Indexed: 10/20/2023] Open
Abstract
BACKGROUND Although patients with interstitial pneumonia pattern (ILD-UIP) and acute exacerbation (AE) leading to severe acute respiratory failure may require invasive mechanical ventilation (MV), physiological data on lung mechanics during MV are lacking. We aimed at describing the physiological effect of lung-protective ventilation in patients with AE-ILD-UIP compared with primary ARDS. METHODS Partitioned lung and chest wall mechanics were assessed in a series of AE-ILD-UIP patients matched 1:1 with primary ARDS as controls (based on BMI and PaO2/FiO2 ratio). Three PEEP levels (zero = ZEEP, 4-8 cmH2O = PEEPLOW, and titrated to achieve positive end-expiratory transpulmonary pressure PL,EE = PEEPTITRATED) were used for measurements. RESULTS Ten AE-ILD-UIP patients and 10 matched ARDS were included. In AE-ILD-UIP median PL,EE at ZEEP was - 4.3 [- 7.6- - 2.3] cmH2O and lung elastance (EL) 44 [40-51] cmH2O/L. At PEEPLOW, PL,EE remained negative and EL did not change (p = 0.995) versus ZEEP. At PEEPTITRATED, PL,EE increased to 0.8 [0.3-1.5] cmH2O and EL to 49 [43-59] (p = 0.004 and p < 0.001 compared to ZEEP and PEEPLOW, respectively). ΔPL decreased at PEEPLOW (p = 0.018) and increased at PEEPTITRATED (p = 0.003). In matched ARDS control PEEP titration to obtain a positive PL,EE did not result in significant changes in EL and ΔPL. CONCLUSIONS In mechanically ventilated AE-ILD-UIP patients, differently than in patients with primary ARDS, PEEP titrated to obtain a positive PL,EE significantly worsened lung mechanics.
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Affiliation(s)
- Roberto Tonelli
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Clinical and Experimental Medicine PhD Program, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Salvatore Grasso
- Dipartimento di Medicina di Precisione e Rigenerativa e Area Ionica (DiMePre-J) Sezione di Anestesiologia e Rianimazione, Università degli Studi di Bari "Aldo Moro", Ospedale Policlinico, Bari, Italy
| | - Andrea Cortegiani
- Department of Surgical, Oncological and Oral Science (Di.Chir.On.S.), University of Palermo, Palermo, Italy
- Department of Anesthesia, Intensive Care and Emergency, Policlinico Paolo Giaccone, Palermo, Italy
| | - Lorenzo Ball
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
- Anesthesia and Critical Care, San Martino Policlinico Hospital, IRCCS for Oncology and Neurosciences, Genoa, Italy
| | - Ivana Castaniere
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Luca Tabbì
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
| | - Riccardo Fantini
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
| | - Dario Andrisani
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Clinical and Experimental Medicine PhD Program, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Filippo Gozzi
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Clinical and Experimental Medicine PhD Program, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Antonio Moretti
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Giulia Bruzzi
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Linda Manicardi
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Stefania Cerri
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Anna Valeria Samarelli
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Giulia Raineri
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
| | - Francesco Murgolo
- Dipartimento di Medicina di Precisione e Rigenerativa e Area Ionica (DiMePre-J) Sezione di Anestesiologia e Rianimazione, Università degli Studi di Bari "Aldo Moro", Ospedale Policlinico, Bari, Italy
| | - Andrea Carzoli
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
| | - Rossella Di Mussi
- Dipartimento di Medicina di Precisione e Rigenerativa e Area Ionica (DiMePre-J) Sezione di Anestesiologia e Rianimazione, Università degli Studi di Bari "Aldo Moro", Ospedale Policlinico, Bari, Italy
| | | | - Raffaella Rizzoni
- Department of Engineering, University of Ferrara, Via Saragat 1, Ferrara, Italy
| | - Giacomo Grasselli
- Dipartimento di Anestesia, Rianimazione e Emergenza-Urgenza, Fondazione IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico) Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Enrico Clini
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy.
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy.
- Laboratory of Experimental Pneumology, University Hospital of Modena, Policlinico, UNIMORE, Università degli Studi di Modena e Reggio Emilia, Modena, Italy.
| | - Alessandro Marchioni
- Respiratory Diseases Unit, Department of Medical and Surgical Sciences, University Hospital of Modena, University of Modena Reggio Emilia, Modena, Italy
- Laboratory of Cell Therapies and Respiratory Medicine, Department of Medical and Surgical Sciences for Children and Adults, University Hospital of Modena, Modena, Italy
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11
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Geitner CM, Becher T, Frerichs I, Weiler N, Bates JHT, Wall WA. An approach to study recruitment/derecruitment dynamics in a patient-specific computational model of an injured human lung. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2023; 39:e3745. [PMID: 37403527 DOI: 10.1002/cnm.3745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 05/04/2023] [Accepted: 06/04/2023] [Indexed: 07/06/2023]
Abstract
We present a new approach for physics-based computational modeling of diseased human lungs. Our main object is the development of a model that takes the novel step of incorporating the dynamics of airway recruitment/derecruitment into an anatomically accurate, spatially resolved model of respiratory system mechanics, and the relation of these dynamics to airway dimensions and the biophysical properties of the lining fluid. The importance of our approach is that it potentially allows for more accurate predictions of where mechanical stress foci arise in the lungs, since it is at these locations that injury is thought to arise and propagate from. We match the model to data from a patient with acute respiratory distress syndrome (ARDS) to demonstrate the potential of the model for revealing the underlying derangements in ARDS in a patient-specific manner. To achieve this, the specific geometry of the lung and its heterogeneous pattern of injury are extracted from medical CT images. The mechanical behavior of the model is tailored to the patient's respiratory mechanics using measured ventilation data. In retrospective simulations of various clinically performed, pressure-driven ventilation profiles, the model adequately reproduces clinical quantities measured in the patient such as tidal volume and change in pleural pressure. The model also exhibits physiologically reasonable lung recruitment dynamics and has the spatial resolution to allow the study of local mechanical quantities such as alveolar strains. This modeling approach advances our ability to perform patient-specific studies in silico, opening the way to personalized therapies that will optimize patient outcomes.
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Affiliation(s)
- Carolin M Geitner
- Institute for Computational Mechanics, Department of Engineering Physics & Computation, TUM School of Engineering and Design, Technical University of Munich, Garching b. Muenchen, Germany
| | - Tobias Becher
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Norbert Weiler
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Jason H T Bates
- Department of Medicine, University of Vermont College of Medicine, Burlington, Vermont, USA
| | - Wolfgang A Wall
- Institute for Computational Mechanics, Department of Engineering Physics & Computation, TUM School of Engineering and Design, Technical University of Munich, Garching b. Muenchen, Germany
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12
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Bates JHT, Nieman GF, Kollisch-Singule M, Gaver DP. Ventilator-Induced Lung Injury as a Dynamic Balance Between Epithelial Cell Damage and Recovery. Ann Biomed Eng 2023; 51:1052-1062. [PMID: 37000319 DOI: 10.1007/s10439-023-03186-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 03/15/2023] [Indexed: 04/01/2023]
Abstract
Acute respiratory distress syndrome (ARDS) has a high mortality rate that is due in part to ventilator-induced lung injury (VILI). Nevertheless, the majority of patients eventually recover, which means that their innate reparative capacities eventually prevail. Since there are currently no medical therapies for ARDS, minimizing its mortality thus amounts to achieving an optimal balance between spontaneous tissue repair versus the generation of VILI. In order to understand this balance better, we developed a mathematical model of the onset and recovery of VILI that incorporates two hypotheses: (1) a novel multi-hit hypothesis of epithelial barrier failure, and (2) a previously articulated rich-get-richer hypothesis of the interaction between atelectrauma and volutrauma. Together, these concepts explain why VILI appears in a normal lung only after an initial latent period of injurious mechanical ventilation. In addition, they provide a mechanistic explanation for the observed synergy between atelectrauma and volutrauma. The model recapitulates the key features of previously published in vitro measurements of barrier function in an epithelial monolayer and in vivo measurements of lung function in mice subjected to injurious mechanical ventilation. This provides a framework for understanding the dynamic balance between factors responsible for the generation of and recovery from VILI.
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Affiliation(s)
- Jason H T Bates
- Department of Medicine, University of Vermont, Burlington, VT, 05405, USA.
- Department of Medicine, Larner College of Medicine, 149 Beaumont Avenue, Burlington, 05405-0075, USA.
| | - Gary F Nieman
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, USA
| | | | - Donald P Gaver
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, USA
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13
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Knudsen L, Hummel B, Wrede C, Zimmermann R, Perlman CE, Smith BJ. Acinar micromechanics in health and lung injury: what we have learned from quantitative morphology. Front Physiol 2023; 14:1142221. [PMID: 37025383 PMCID: PMC10070844 DOI: 10.3389/fphys.2023.1142221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 03/09/2023] [Indexed: 04/08/2023] Open
Abstract
Within the pulmonary acini ventilation and blood perfusion are brought together on a huge surface area separated by a very thin blood-gas barrier of tissue components to allow efficient gas exchange. During ventilation pulmonary acini are cyclically subjected to deformations which become manifest in changes of the dimensions of both alveolar and ductal airspaces as well as the interalveolar septa, composed of a dense capillary network and the delicate tissue layer forming the blood-gas barrier. These ventilation-related changes are referred to as micromechanics. In lung diseases, abnormalities in acinar micromechanics can be linked with injurious stresses and strains acting on the blood-gas barrier. The mechanisms by which interalveolar septa and the blood-gas barrier adapt to an increase in alveolar volume have been suggested to include unfolding, stretching, or changes in shape other than stretching and unfolding. Folding results in the formation of pleats in which alveolar epithelium is not exposed to air and parts of the blood-gas barrier are folded on each other. The opening of a collapsed alveolus (recruitment) can be considered as an extreme variant of septal wall unfolding. Alveolar recruitment can be detected with imaging techniques which achieve light microscopic resolution. Unfolding of pleats and stretching of the blood-gas barrier, however, require electron microscopic resolution to identify the basement membrane. While stretching results in an increase of the area of the basement membrane, unfolding of pleats and shape changes do not. Real time visualization of these processes, however, is currently not possible. In this review we provide an overview of septal wall micromechanics with focus on unfolding/folding as well as stretching. At the same time we provide a state-of-the-art design-based stereology methodology to quantify microarchitecture of alveoli and interalveolar septa based on different imaging techniques and design-based stereology.
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Affiliation(s)
- Lars Knudsen
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Centre for Lung Research (DZL), Hannover, Germany
| | - Benjamin Hummel
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Christoph Wrede
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
- Research Core Unit Electron Microscopy, Hannover Medical School, Hannover, Germany
| | - Richard Zimmermann
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Carrie E Perlman
- Department of Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ, United States
| | - Bradford J Smith
- Department of Bioengineering, College of Engineering Design and Computing, University of Colorado Denver | Anschutz Medical Campus, Aurora, CO, United States
- Department of Pediatric Pulmonary and Sleep Medicine, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
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14
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Kjellberg M, Sanchez-Crespo A, Jonsson B. First week of life respiratory management and pulmonary ventilation/perfusion matching in infants with bronchopulmonary dysplasia: a retrospective observational study. J Perinatol 2023; 43:317-323. [PMID: 36456603 PMCID: PMC9991908 DOI: 10.1038/s41372-022-01569-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 11/11/2022] [Accepted: 11/18/2022] [Indexed: 12/05/2022]
Abstract
OBJECTIVE To investigate the association between early neonatal respiratory management in infants with bronchopulmonary dysplasia (BPD) and the degree of pulmonary ventilation perfusion-matching (V/Q) at term. METHODS 30 preterm infants with a diagnosis of BPD who were initially treated with either controlled mechanical ventilation/continuous positive airway pressure (CMV/CPAP) (n = 14) or high-frequency oscillatory ventilation (HFOV) using a high lung-volume strategy (n = 16) were retrospectively included in this study. All infants underwent pulmonary V/Q single photon emission computed tomography at a median postmenstrual age of 37 weeks. RESULTS Infants treated with HFOV had significantly larger proportion of the lung with matched V/Q as compared to infants treated with CMV/CPAP, median (interquartile range) 60.4% (55.5-66.0%) and 45.8% (37.8-53.1%) respectively (p = 0.01). CONCLUSIONS In infants who needed mechanical ventilation the first week of life and later developed BPD an association was observed between treatment with a HFOV and better pulmonary V/Q matching at near-term age.
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Affiliation(s)
- Malin Kjellberg
- Department of Woman and Child Health, Department of Neonatology, Karolinska Institute, Stockholm, Sweden
| | - Alejandro Sanchez-Crespo
- Department of Oncology-Pathology, Karolinska Institute, Stockholm, Sweden. .,Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden.
| | - Baldvin Jonsson
- Department of Woman and Child Health, Department of Neonatology, Karolinska Institute, Stockholm, Sweden
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15
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Khoa ND, Phuong NL, Tani K, Inthavong K, Ito K. In-silico decongested trial effects on the impaired breathing function of a bulldog suffering from severe brachycephalic obstructive airway syndrome. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2023; 228:107243. [PMID: 36403552 DOI: 10.1016/j.cmpb.2022.107243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 11/10/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND AND OBJECTIVE Brachycephalic obstructive airway syndrome (BOAS) susceptible dogs (e.g., French bulldog), suffer health complications related to deficient breathing primarily due to anatomical airway geometry. Surgical interventions are known to provide acceptable functional and cosmetic results; however, the long-term post-surgery outcome is not well known. In silico analysis provides an objective measure to quantify the respiratory function in postoperative dogs which is critical for successful long-term outcomes. A virtual surgery to open the airway can explore the ability for improved breathing in an obstructed airway of a patient dog, thus supporting surgeons in pre-surgery planning using computational fluid dynamics. METHODS In this study five surgical interventions were generated with a gradual increment of decongested levels in a bulldog based on computed tomography images. The effects of the decongested airways on the breathing function of a patient bulldog, i.e., airflow characteristics, pressure drop, wall shear stress, and air-conditioning capacity, were quantified by benchmarking against a clinically healthy bulldog using computational fluid dynamics (CFD) method. RESULTS Our findings demonstrated a promising decrease in excessive airstream velocity, pressure drop, and wall shear stress in virtual surgical scenarios, while constantly preserving adequate air-conditioning efficiency. A linear fit curve was proposed to correlate the reduction in the pressure drop and decongested level. CONCLUSIONS The in silico analysis is a viable tool providing visual and quantitative insight into new unexplored surgical techniques.
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Affiliation(s)
- Nguyen Dang Khoa
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1, Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan.
| | - Nguyen Lu Phuong
- Faculty of Environment, University of Natural Resources and Environment, Ho Chi Minh, Viet Nam
| | - Kenji Tani
- Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi, Yamaguchi, Japan
| | - Kiao Inthavong
- School of Engineering, Mechanical & Automotive, RMIT University, Melbourne, Australia
| | - Kazuhide Ito
- Faculty of Engineering Sciences, Kyushu University, Kasuga, Fukuoka, Japan
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16
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Sullivan KM, Ko E, Kim EM, Ballance WC, Ito JD, Chalifoux M, Kim YJ, Bashir R, Kong H. Extracellular Microenvironmental Control for Organoid Assembly. TISSUE ENGINEERING. PART B, REVIEWS 2022; 28:1209-1222. [PMID: 35451330 PMCID: PMC9836674 DOI: 10.1089/ten.teb.2021.0186] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 03/04/2022] [Indexed: 01/22/2023]
Abstract
Organoids, which are multicellular clusters with similar physiological functions to living organs, have gained increasing attention in bioengineering. As organoids become more advanced, methods to form complex structures continue to develop. There is evidence that the extracellular microenvironment can regulate organoid quality. The extracellular microenvironment consists of soluble bioactive molecules, extracellular matrix, and biofluid flow. However, few efforts have been made to discuss the microenvironment optimal to engineer specific organoids. Therefore, this review article examines the extent to which engineered extracellular microenvironments regulate organoid quality. First, we summarize the natural tissue and organ's unique chemical and mechanical properties, guiding researchers to design an extracellular microenvironment used for organoid engineering. Then, we summarize how the microenvironments contribute to the formation and growth of the brain, lung, intestine, liver, retinal, and kidney organoids. The approaches to forming and evaluating the resulting organoids are also discussed in detail. Impact statement Organoids, which are multicellular clusters with similar physiological function to living organs, have been gaining increasing attention in bioengineering. As organoids become more advanced, methods to form complex structures continue to develop. This review article focuses on recent efforts to engineer the extracellular microenvironment in organoid research. We summarized the natural organ's microenvironment, which informs researchers of key factors that can influence organoid formation. Then, we summarize how these microenvironmental controls significantly contribute to the formation and growth of the corresponding brain, lung, intestine, liver, retinal, and kidney organoids. The approaches to forming and evaluating the resulting organoids are discussed in detail, including extracellular matrix choice and properties, culture methods, and the evaluation of the morphology and functionality through imaging and biochemical analysis.
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Affiliation(s)
- Kathryn M. Sullivan
- Department of Bioengineering, and University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
| | - Eunkyung Ko
- Department of Bioengineering, and University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
| | - Eun Mi Kim
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
| | - William C. Ballance
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
| | - John D. Ito
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
| | - Madeleine Chalifoux
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
| | - Young Jun Kim
- Environmental Safety Group, Korea Institute of Science and Technology (KIST–Europe), Saarbrucken, Germany
| | - Rashid Bashir
- Department of Bioengineering, and University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
| | - Hyunjoon Kong
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois, USA
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17
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Ramcharran H, Bates JHT, Satalin J, Blair S, Andrews PL, Gaver DP, Gatto LA, Wang G, Ghosh AJ, Robedee B, Vossler J, Habashi NM, Daphtary N, Kollisch-Singule M, Nieman GF. Protective ventilation in a pig model of acute lung injury: timing is as important as pressure. J Appl Physiol (1985) 2022; 133:1093-1105. [PMID: 36135956 PMCID: PMC9621707 DOI: 10.1152/japplphysiol.00312.2022] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/26/2022] [Accepted: 09/19/2022] [Indexed: 11/22/2022] Open
Abstract
Ventilator-induced lung injury (VILI) is a significant risk for patients with acute respiratory distress syndrome (ARDS). Management of the patient with ARDS is currently dominated by the use of low tidal volume mechanical ventilation, the presumption being that this mitigates overdistension (OD) injury to the remaining normal lung tissue. Evidence exists, however, that it may be more important to avoid cyclic recruitment and derecruitment (RD) of lung units, although the relative roles of OD and RD in VILI remain unclear. Forty pigs had a heterogeneous lung injury induced by Tween instillation and were randomized into four groups (n = 10 each) with higher (↑) or lower (↓) levels of OD and/or RD imposed using airway pressure release ventilation (APRV). OD was increased by setting inspiratory airway pressure to 40 cmH2O and lessened with 28 cmH2O. RD was attenuated using a short duration of expiration (∼0.45 s) and increased with a longer duration (∼1.0 s). All groups developed mild ARDS following injury. RD ↑ OD↑ caused the greatest degree of lung injury as determined by [Formula: see text]/[Formula: see text] ratio (226.1 ± 41.4 mmHg). RD ↑ OD↓ ([Formula: see text]/[Formula: see text]= 333.9 ± 33.1 mmHg) and RD ↓ OD↑ ([Formula: see text]/[Formula: see text] = 377.4 ± 43.2 mmHg) were both moderately injurious, whereas RD ↓ OD↓ ([Formula: see text]/[Formula: see text] = 472.3 ± 22.2 mmHg; P < 0.05) was least injurious. Both tidal volume and driving pressure were essentially identical in the RD ↑ OD↓ and RD ↓ OD↑ groups. We, therefore, conclude that considerations of expiratory time may be at least as important as pressure for safely ventilating the injured lung.NEW & NOTEWORTHY In a large animal model of ARDS, recruitment/derecruitment caused greater VILI than overdistension, whereas both mechanisms together caused severe lung damage. These findings suggest that eliminating cyclic recruitment and derecruitment during mechanical ventilation should be a preeminent management goal for the patient with ARDS. The airway pressure release ventilation (APRV) mode of mechanical ventilation can achieve this if delivered with an expiratory duration (TLow) that is brief enough to prevent derecruitment at end expiration.
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Affiliation(s)
| | | | | | - Sarah Blair
- SUNY Upstate Medical University, Syracuse, New York
| | | | | | | | - Guirong Wang
- SUNY Upstate Medical University, Syracuse, New York
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18
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Chirico RN, de Matos NA, Castro TDF, Cândido LDS, Miranda AG, Costa GDP, Talvani A, Cangussú SD, Brochard L, Bezerra FS. The exogenous surfactant pre-treatment attenuates ventilator-induced lung injury in adult rats. Respir Physiol Neurobiol 2022; 302:103911. [PMID: 35430285 DOI: 10.1016/j.resp.2022.103911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 03/10/2022] [Accepted: 04/10/2022] [Indexed: 10/18/2022]
Abstract
Mechanical ventilation is an essential supportive therapy in the treatment of critical patients, and it aims to maintain adequate gas exchange; however, it can also contribute to inflammation and oxidative stress, thus leading to lung injury. We tested the hypothesis that exogenous surfactant administration will be protective against ventilator-induced lung injury in adult healthy Wistar rats both because of its anti-inflammatory properties as well as its role in preventing alveolar collapse at end-expiration. Thus, the effect of intranasal instillation of a bovine exogenous surfactant was tested in Wistar rats submitted to mechanical ventilation. The animals were divided into four groups: (1) CONTROL; (2) SURFACTANT; (3) Mechanical ventilation (MV); (4) MV with pre-treatment with surfactant (MVSURFACTANT). The MV and MVSURFACTANT were submitted to MV with high tidal volume (12 mL/kg) for 1 h. After the experimental protocol, all animals were euthanized and the arterial blood, bronchoalveolar lavage fluid and lungs were collected for biochemical, immunoenzymatic assay, arterial blood gases, and morphometric analyzes. The Wistar rats that received exogenous surfactant (Survanta®) by intranasal instillation before MV demonstrated reduced levels of leukocytes, inflammatory biomarkers such as CCL2, IL-1, IL-6 and TNF-α. Furthermore, it prevented oxidative damage by reducing lipid peroxidation and protein carbonylation as well as histological pattern changes of pulmonary parenchyma. Our data indicate that exogenous surfactant attenuated lung inflammation and redox imbalance induced by mechanical ventilation in healthy adult rats suggesting a preventive effect on ventilator-induced lung injury.
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Affiliation(s)
- Rafael Neto Chirico
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - Natália Alves de Matos
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - Thalles de Freitas Castro
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - Leandro da Silva Cândido
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - Amanda Gonçalves Miranda
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - Guilherme de Paula Costa
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - André Talvani
- Laboratory of Immunobiology of Inflammation (LABIIN), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - Sílvia Dantas Cangussú
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil
| | - Laurent Brochard
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto 416-360-4000, Ontario, Canada; Keenan Research Centre, Li KaShing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Frank Silva Bezerra
- Laboratory of Experimental Pathophysiology (LAFEx), Department of Biological Sciences, Center of Research in Biological Sciences, Federal University of Ouro Preto, 35400-000 Minas Gerais, Brazil; Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto 416-360-4000, Ontario, Canada; Keenan Research Centre, Li KaShing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.
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19
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Yamaguchi E, Yao J, Aymond A, Chrisey DB, Nieman GF, Bates JHT, Gaver DP. Electric Cell-Substrate Impedance Sensing (ECIS) as a Platform for Evaluating Barrier-Function Susceptibility and Damage from Pulmonary Atelectrauma. BIOSENSORS 2022; 12:390. [PMID: 35735538 PMCID: PMC9221382 DOI: 10.3390/bios12060390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 05/27/2022] [Accepted: 06/02/2022] [Indexed: 11/16/2022]
Abstract
Biophysical insults that either reduce barrier function (COVID-19, smoke inhalation, aspiration, and inflammation) or increase mechanical stress (surfactant dysfunction) make the lung more susceptible to atelectrauma. We investigate the susceptibility and time-dependent disruption of barrier function associated with pulmonary atelectrauma of epithelial cells that occurs in acute respiratory distress syndrome (ARDS) and ventilator-induced lung injury (VILI). This in vitro study was performed using Electric Cell-substrate Impedance Sensing (ECIS) as a noninvasive evaluating technique for repetitive stress stimulus/response on monolayers of the human lung epithelial cell line NCI-H441. Atelectrauma was mimicked through recruitment/derecruitment (RD) of a semi-infinite air bubble to the fluid-occluded micro-channel. We show that a confluent monolayer with a high level of barrier function is nearly impervious to atelectrauma for hundreds of RD events. Nevertheless, barrier function is eventually diminished, and after a critical number of RD insults, the monolayer disintegrates exponentially. Confluent layers with lower initial barrier function are less resilient. These results indicate that the first line of defense from atelectrauma resides with intercellular binding. After disruption, the epithelial layer community protection is diminished and atelectrauma ensues. ECIS may provide a platform for identifying damaging stimuli, ventilation scenarios, or pharmaceuticals that can reduce susceptibility or enhance barrier-function recovery.
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Affiliation(s)
- Eiichiro Yamaguchi
- Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118, USA; (J.Y.); (A.A.)
| | - Joshua Yao
- Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118, USA; (J.Y.); (A.A.)
| | - Allison Aymond
- Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118, USA; (J.Y.); (A.A.)
| | - Douglas B. Chrisey
- Department of Physics and Engineering Physics, Tulane University, New Orleans, LA 70118, USA;
| | - Gary F. Nieman
- Department of Surgery, Upstate Medical University, Syracuse, NY 13210, USA;
| | - Jason H. T. Bates
- Department of Medicine, University of Vermont, Burlington, VT 05405, USA;
| | - Donald P. Gaver
- Department of Biomedical Engineering, Tulane University, New Orleans, LA 70118, USA; (J.Y.); (A.A.)
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20
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Neelakantan S, Xin Y, Gaver DP, Cereda M, Rizi R, Smith BJ, Avazmohammadi R. Computational lung modelling in respiratory medicine. J R Soc Interface 2022; 19:20220062. [PMID: 35673857 PMCID: PMC9174712 DOI: 10.1098/rsif.2022.0062] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/03/2022] [Indexed: 11/12/2022] Open
Abstract
Computational modelling of the lungs is an active field of study that integrates computational advances with lung biophysics, biomechanics, physiology and medical imaging to promote individualized diagnosis, prognosis and therapy evaluation in lung diseases. The complex and hierarchical architecture of the lung offers a rich, but also challenging, research area demanding a cross-scale understanding of lung mechanics and advanced computational tools to effectively model lung biomechanics in both health and disease. Various approaches have been proposed to study different aspects of respiration, ranging from compartmental to discrete micromechanical and continuum representations of the lungs. This article reviews several developments in computational lung modelling and how they are integrated with preclinical and clinical data. We begin with a description of lung anatomy and how different tissue components across multiple length scales affect lung mechanics at the organ level. We then review common physiological and imaging data acquisition methods used to inform modelling efforts. Building on these reviews, we next present a selection of model-based paradigms that integrate data acquisitions with modelling to understand, simulate and predict lung dynamics in health and disease. Finally, we highlight possible future directions where computational modelling can improve our understanding of the structure-function relationship in the lung.
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Affiliation(s)
- Sunder Neelakantan
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
| | - Yi Xin
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Donald P. Gaver
- Department of Biomedical Engineering, Tulane University, New Orleans, LA, USA
| | - Maurizio Cereda
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rahim Rizi
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Bradford J. Smith
- Department of Bioengineering, University of Colorado Denver | Anschutz Medical Campus, Aurora, CO, USA
- Department of Pediatric Pulmonary and Sleep Medicine, School of Medicine, University of Colorado, Aurora, CO, USA
| | - Reza Avazmohammadi
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
- J. Mike Walker '66 Department of Mechanical Engineering, Texas A&M University, College Station, TX, USA
- Department of Cardiovascular Sciences, Houston Methodist Academic Institute, Houston, TX, USA
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21
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Abstract
Pulmonary atelectasis is common in the perioperative period. Physiologically, it is produced when collapsing forces derived from positive pleural pressure and surface tension overcome expanding forces from alveolar pressure and parenchymal tethering. Atelectasis impairs blood oxygenation and reduces lung compliance. It is increasingly recognized that it can also induce local tissue biologic responses, such as inflammation, local immune dysfunction, and damage of the alveolar-capillary barrier, with potential loss of lung fluid clearance, increased lung protein permeability, and susceptibility to infection, factors that can initiate or exaggerate lung injury. Mechanical ventilation of a heterogeneously aerated lung (e.g., in the presence of atelectatic lung tissue) involves biomechanical processes that may precipitate further lung damage: concentration of mechanical forces, propagation of gas-liquid interfaces, and remote overdistension. Knowledge of such pathophysiologic mechanisms of atelectasis and their consequences in the healthy and diseased lung should guide optimal clinical management.
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22
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Nof E, Artzy‐Schnirman A, Bhardwaj S, Sabatan H, Waisman D, Hochwald O, Gruber M, Borenstein‐Levin L, Sznitman J. Ventilation‐induced epithelial injury drives biological onset of lung trauma in vitro and is mitigated with prophylactic anti‐inflammatory therapeutics. Bioeng Transl Med 2021; 7:e10271. [PMID: 35600654 PMCID: PMC9115701 DOI: 10.1002/btm2.10271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/27/2021] [Accepted: 11/08/2021] [Indexed: 01/25/2023] Open
Abstract
Mortality rates among patients suffering from acute respiratory failure remain perplexingly high despite the maintenance of blood oxygen homeostasis during ventilatory support. The biotrauma hypothesis advocates that mechanical forces from invasive ventilation trigger immunological mediators that spread systemically. Yet, how these forces elicit an immune response remains unclear. Here, a biomimetic in vitro three‐dimensional (3D) upper airways model allows to recapitulate lung injury and immune responses induced during invasive mechanical ventilation in neonates. Under such ventilatory support, flow‐induced stresses injure the bronchial epithelium of the intubated airways model and directly modulate epithelial cell inflammatory cytokine secretion associated with pulmonary injury. Fluorescence microscopy and biochemical analyses reveal site‐specific susceptibility to epithelial erosion in airways from jet‐flow impaction and are linked to increases in cell apoptosis and modulated secretions of cytokines IL‐6, ‐8, and ‐10. In an effort to mitigate the onset of biotrauma, prophylactic pharmacological treatment with Montelukast, a leukotriene receptor antagonist, reduces apoptosis and pro‐inflammatory signaling during invasive ventilation of the in vitro model. This 3D airway platform points to a previously overlooked origin of lung injury and showcases translational opportunities in preclinical pulmonary research toward protective therapies and improved protocols for patient care.
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Affiliation(s)
- Eliram Nof
- Faculty of Biomedical Engineering Technion ‐ Israel Institute of Technology Haifa Israel
| | - Arbel Artzy‐Schnirman
- Faculty of Biomedical Engineering Technion ‐ Israel Institute of Technology Haifa Israel
| | - Saurabh Bhardwaj
- Faculty of Biomedical Engineering Technion ‐ Israel Institute of Technology Haifa Israel
| | - Hadas Sabatan
- Faculty of Biomedical Engineering Technion ‐ Israel Institute of Technology Haifa Israel
| | - Dan Waisman
- Faculty of Medicine Technion ‐ Israel Institute of Technology Haifa Israel
- Department of Neonatology Carmel Medical Center Haifa Israel
| | - Ori Hochwald
- Faculty of Medicine Technion ‐ Israel Institute of Technology Haifa Israel
- Department of Neonatology Ruth Rappaport Children's Hospital, Rambam Healthcare Haifa Israel
| | - Maayan Gruber
- Azrieli Faculty of Medicine Bar‐Ilan University Safed Israel
- Department of Otolaryngology‐Head and Neck Surgery Galilee Medical Center Nahariya Israel
| | - Liron Borenstein‐Levin
- Faculty of Medicine Technion ‐ Israel Institute of Technology Haifa Israel
- Department of Neonatology Ruth Rappaport Children's Hospital, Rambam Healthcare Haifa Israel
| | - Josué Sznitman
- Faculty of Biomedical Engineering Technion ‐ Israel Institute of Technology Haifa Israel
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23
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Novak C, Ballinger MN, Ghadiali S. Mechanobiology of Pulmonary Diseases: A Review of Engineering Tools to Understand Lung Mechanotransduction. J Biomech Eng 2021; 143:110801. [PMID: 33973005 PMCID: PMC8299813 DOI: 10.1115/1.4051118] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 05/01/2021] [Indexed: 12/17/2022]
Abstract
Cells within the lung micro-environment are continuously subjected to dynamic mechanical stimuli which are converted into biochemical signaling events in a process known as mechanotransduction. In pulmonary diseases, the abrogated mechanical conditions modify the homeostatic signaling which influences cellular phenotype and disease progression. The use of in vitro models has significantly expanded our understanding of lung mechanotransduction mechanisms. However, our ability to match complex facets of the lung including three-dimensionality, multicellular interactions, and multiple simultaneous forces is limited and it has proven difficult to replicate and control these factors in vitro. The goal of this review is to (a) outline the anatomy of the pulmonary system and the mechanical stimuli that reside therein, (b) describe how disease impacts the mechanical micro-environment of the lung, and (c) summarize how existing in vitro models have contributed to our current understanding of pulmonary mechanotransduction. We also highlight critical needs in the pulmonary mechanotransduction field with an emphasis on next-generation devices that can simulate the complex mechanical and cellular environment of the lung. This review provides a comprehensive basis for understanding the current state of knowledge in pulmonary mechanotransduction and identifying the areas for future research.
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Affiliation(s)
- Caymen Novak
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Davis Heart and Lung Research Institute, The Ohio State University, Wexner Medical Center, 473 West 12th Avenue, Columbus, OH 43210
| | - Megan N. Ballinger
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Davis Heart and Lung Research Institute, The Ohio State University, Wexner Medical Center, 473 West 12th Avenue, Columbus, OH 43210
| | - Samir Ghadiali
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, The Davis Heart and Lung Research Institute, The Ohio State University, Wexner Medical Center, 473 West 12th Avenue, Columbus, OH 43210; Department of Biomedical Engineering, The Ohio State University, 2124N Fontana Labs, 140 West 19th Avenue, Columbus, OH 43210
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24
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Wang D, Cong Y, Deng Q, Han X, Zhang S, Zhao L, Luo Y, Zhang X. Physiological and Disease Models of Respiratory System Based on Organ-on-a-Chip Technology. MICROMACHINES 2021; 12:mi12091106. [PMID: 34577749 PMCID: PMC8467891 DOI: 10.3390/mi12091106] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/09/2021] [Accepted: 06/18/2021] [Indexed: 12/11/2022]
Abstract
The pathogenesis of respiratory diseases is complex, and its occurrence and development also involve a series of pathological processes. The present research methods are have difficulty simulating the natural developing state of the disease in the body, and the results cannot reflect the real growth state and function in vivo. The development of microfluidic chip technology provides a technical platform for better research on respiratory diseases. The size of its microchannel can be similar to the space for cell growth in vivo. In addition, organ-on-a-chip can achieve long-term co-cultivation of multiple cells and produce precisely controllable fluid shear force, periodically changing mechanical force, and perfusate with varying solute concentration gradient. To sum up, the chip can be used to analyze the specific pathophysiological changes of organs meticulously, and it is widely used in scientific research on respiratory diseases. The focus of this review is to describe and discuss current studies of artificial respiratory systems based on organ-on-a-chip technology and to summarize their applications in the real world.
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Affiliation(s)
- Di Wang
- College of Pharmaceutical Science, Soochow University, Suzhou 215123, China; (D.W.); (Q.D.); (X.H.)
- Department of Pulmonary and Critical Care Medicine, Second Medical School, China Medical University, Shenyang 110004, China
| | - Ye Cong
- State Key Laboratory of Fine Chemicals, Department of Pharmaceutical Sciences, School of Chemical Engineering, Dalian University of Technology, Dalian 116023, China; (Y.C.); (S.Z.)
| | - Quanfeng Deng
- College of Pharmaceutical Science, Soochow University, Suzhou 215123, China; (D.W.); (Q.D.); (X.H.)
| | - Xiahe Han
- College of Pharmaceutical Science, Soochow University, Suzhou 215123, China; (D.W.); (Q.D.); (X.H.)
| | - Suonan Zhang
- State Key Laboratory of Fine Chemicals, Department of Pharmaceutical Sciences, School of Chemical Engineering, Dalian University of Technology, Dalian 116023, China; (Y.C.); (S.Z.)
| | - Li Zhao
- Department of Pulmonary and Critical Care Medicine, Second Medical School, China Medical University, Shenyang 110004, China
- Correspondence: (L.Z.); (Y.L.); (X.Z.); Tel.: +86-138-4116-9035 (X.Z.)
| | - Yong Luo
- State Key Laboratory of Fine Chemicals, Department of Pharmaceutical Sciences, School of Chemical Engineering, Dalian University of Technology, Dalian 116023, China; (Y.C.); (S.Z.)
- Correspondence: (L.Z.); (Y.L.); (X.Z.); Tel.: +86-138-4116-9035 (X.Z.)
| | - Xiuli Zhang
- College of Pharmaceutical Science, Soochow University, Suzhou 215123, China; (D.W.); (Q.D.); (X.H.)
- Correspondence: (L.Z.); (Y.L.); (X.Z.); Tel.: +86-138-4116-9035 (X.Z.)
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25
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Kolb P, Schundner A, Frick M, Gottschalk KE. In Vitro Measurements of Cellular Forces and their Importance in the Lung-From the Sub- to the Multicellular Scale. Life (Basel) 2021; 11:691. [PMID: 34357063 PMCID: PMC8307149 DOI: 10.3390/life11070691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/09/2021] [Accepted: 07/09/2021] [Indexed: 02/07/2023] Open
Abstract
Throughout life, the body is subjected to various mechanical forces on the organ, tissue, and cellular level. Mechanical stimuli are essential for organ development and function. One organ whose function depends on the tightly connected interplay between mechanical cell properties, biochemical signaling, and external forces is the lung. However, altered mechanical properties or excessive mechanical forces can also drive the onset and progression of severe pulmonary diseases. Characterizing the mechanical properties and forces that affect cell and tissue function is therefore necessary for understanding physiological and pathophysiological mechanisms. In recent years, multiple methods have been developed for cellular force measurements at multiple length scales, from subcellular forces to measuring the collective behavior of heterogeneous cellular networks. In this short review, we give a brief overview of the mechanical forces at play on the cellular level in the lung. We then focus on the technological aspects of measuring cellular forces at many length scales. We describe tools with a subcellular resolution and elaborate measurement techniques for collective multicellular units. Many of the technologies described are by no means restricted to lung research and have already been applied successfully to cells from various other tissues. However, integrating the knowledge gained from these multi-scale measurements in a unifying framework is still a major future challenge.
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Affiliation(s)
- Peter Kolb
- Institute of Experimental Physics, Ulm University, 89069 Ulm, Germany;
| | - Annika Schundner
- Institute of General Physiology, Ulm University, 89069 Ulm, Germany;
| | - Manfred Frick
- Institute of General Physiology, Ulm University, 89069 Ulm, Germany;
| | - Kay-E. Gottschalk
- Institute of Experimental Physics, Ulm University, 89069 Ulm, Germany;
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26
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Chen Z, Hu Z, Zhong M, Deng L, Tao J, Song Y. Potential effect of pulmonary fluid viscosity on positive end-expiratory pressure and regional distribution of lung ventilation in acute respiratory distress syndrome. Clin Biomech (Bristol, Avon) 2021; 87:105407. [PMID: 34214731 PMCID: PMC9756214 DOI: 10.1016/j.clinbiomech.2021.105407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 02/03/2021] [Accepted: 06/03/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Computational fluid dynamic simulations have showed that the elevated viscosity of pulmonary fluids may increase the likelihood of airway closure, thus exacerbating inhomogeneity of regional lung ventilation. Unfortunately, there have been few studies directed toward measurements of viscosity of pulmonary fluids and its effect on airway opening pressure and regional distribution of lung ventilation in acute respiratory distress syndrome. METHODS In this study, pulmonary fluids from 8 ARDS patients were measured using a cone and plate rheometer on days 1, 3, 7 and 14 in the treatment of the disorder. Ventilator settings were simultaneously recorded, including tidal volume, positive end-expiratory pressure, fraction of inspired oxygen (FiO2), and so on. The regional distribution of lung ventilation was monitored by a bedside electrical impedance tomography system. FINDINGS The results showed that rheological properties of pulmonary fluids behaved as either Newtonian or non-Newtonian across all patients studied. Significant intersubject and intrasubject variations in measured viscosities were observed, spanning ranges from approximately 1 cP to 7 × 104 cP at shear rates between 0.075-750 s-1. The product of the positive end-expiratory airway pressure and fraction of inspired oxygen was well correlated with fluid viscosity in patients with high viscosity pulmonary fluids. Furthermore, lung ventilation in these patients was highly inhomogeneous and influenced by rheology of pulmonary fluids. INTERPRETATION The current findings provided the direct clinical data for theoretical models of airway reopening and may have important clinical implications in explaining inhomogeneity of lung ventilation and selecting initial levels of positive end-expiratory pressure in mechanically ventilated patients.
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Affiliation(s)
- Zhenglong Chen
- School of Medical Instrumentation, Shanghai University of Medicine & Health Sciences, Shanghai, China,NMPA Key Laboratory for Respiratory and Anaesthetic Equipment, Shanghai, China
| | - Zhaoyan Hu
- School of Medical Instrumentation, Shanghai University of Medicine & Health Sciences, Shanghai, China,NMPA Key Laboratory for Respiratory and Anaesthetic Equipment, Shanghai, China
| | - Ming Zhong
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, China,Corresponding author at: Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Xuhui District 200032, Shanghai, China
| | - Linhong Deng
- Institute of Biomedical Engineering and Health Sciences, Changzhou University, Changzhou, China
| | - Jiale Tao
- Department of Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yuanlin Song
- Department of Pulmonary Medicine, Zhongshan Hospital, Fudan University, Shanghai, China,Corresponding author
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27
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Da Silva E, Vogel U, Hougaard KS, Pérez-Gil J, Zuo YY, Sørli JB. An adverse outcome pathway for lung surfactant function inhibition leading to decreased lung function. Curr Res Toxicol 2021; 2:225-236. [PMID: 34345865 PMCID: PMC8320609 DOI: 10.1016/j.crtox.2021.05.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/19/2021] [Accepted: 05/25/2021] [Indexed: 12/27/2022] Open
Abstract
Inhaled substances, such as consumer products, chemicals at the workplace, and nanoparticles, can affect the lung function in several ways. In this paper, we explore the adverse outcome pathway (AOP) that starts when inhaled substances that reach the alveoli inhibit the function of the lung surfactant, and leads to decreased lung function. Lung surfactant covers the inner surface of the alveoli, and regulates the surface tension at the air-liquid interface during breathing. The inhibition of the lung surfactant function leads to alveolar collapse because of the resulting high surface tension at the end of expiration. The collapsed alveoli can be re-opened by inspiration, but this re-opening causes shear stress on cells covering the alveoli. This can damage the alveolar-capillary membrane integrity, allowing blood components to enter the alveolar airspace. Blood components, such as albumin, can interact with the lung surfactant and further inhibit its function. The collapse of the alveoli is responsible for a decrease in the surface area available for blood oxygenation, and it reduces the volume of air that can be inhaled and exhaled. These different key events lead to decreased lung function, characterized by clinical signs of respiratory toxicity and reduced blood oxygenation. Here we present the weight of evidence that supports the AOP, and we give an overview of the methods available in vitro and in vivo to measure each key event of the pathway, and how this AOP can potentially be used in screening for inhalation toxicity.
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Key Words
- AO, adverse outcome
- AOP, adverse outcome pathway
- ARDS, acute respiratory distress syndrome
- Adverse outcome pathway
- Alternative method
- EAGMST, Extended Advisory Group on Molecular Screening and Toxicogenomics
- GHS, Globally Harmonized System of Classification and Labelling of Chemicals
- Inhalation
- KE, key event
- Lung surfactant
- MIE, molecular initiating event
- Nanomaterials
- New approach methodology
- OECD, Organisation for Economic Cooperation and Development
- OI, oxygenation index
- PaO2, dissolved oxygen in the plasma
- SaO2, percentage of hemoglobin saturated with oxygen
- Spray products
- TEER, trans epithelial electrical resistance
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Affiliation(s)
- Emilie Da Silva
- National Research Centre for the Working Environment, Copenhagen, Denmark
- DTU Environment, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Ulla Vogel
- National Research Centre for the Working Environment, Copenhagen, Denmark
- DTU Health Tech, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Karin S. Hougaard
- National Research Centre for the Working Environment, Copenhagen, Denmark
- Department of Public Health, University of Copenhagen, Denmark
| | - Jesus Pérez-Gil
- Faculty of Biology and Research Institute “12 de Octubre (imas12)”, Complutense University, Madrid, Spain
| | - Yi Y. Zuo
- Department of Mechanical Engineering, University of Hawaii at Manoa, Honolulu, HI, United States
| | - Jorid B. Sørli
- National Research Centre for the Working Environment, Copenhagen, Denmark
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28
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Munir B, Xu Y. The steady motion of microbubbles in bifurcating airways: Role of shear-thinning and surface tension. Respir Physiol Neurobiol 2021; 290:103675. [PMID: 33915302 DOI: 10.1016/j.resp.2021.103675] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 04/21/2021] [Indexed: 12/11/2022]
Abstract
Mucous fluid is non-Newtonian secretions in the lower lung airways that accumulates when the alveolar-capillary membrane ruptures during acute respiratory distress syndrome. The mucus fluid has, therefore, different types of non-Newtonian properties like shear-thinning, viscoelasticity, and non-zero yield stress. In this paper, we numerically solved the steady Stokes equations along with arbitrary Eulerian-Lagrangian moving mesh techniques to study the microbubble propagation in a two-dimensional asymmetric bifurcating airway filled with non-Newtonian fluid where the fluid has shear-thinning behavior described by the power-law model. Numerical results show that both shear-thinning and surface tension characterized by the behavior index (n) and Capillary number (Ca), respectively, had a significant impact on microbubble flow patterns and the magnitude of the pressure gradient. At low values of both n and Ca, the microbubble leaves a thin film-thickness with the airway wall while a large and sharp peak of the pressure gradient near the thin bubble tip. Interestingly, increasing both n and Ca, leads to an increase in film thickness and a decrease in the pressure gradient magnitude in both the daughter airway walls. It is observed the magnitude of the pressure gradient is more sensitive to Ca compared to n. We concluded that shear-thinning and surface tension not only significantly impact the patterns of microbubble propagation but also the hydrodynamic stress magnitudes at the airway wall.
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Affiliation(s)
- Bacha Munir
- School of Natural and Applied Sciences, Department of Applied Mathematics, Northwestern Polytechnical University, Xi'an, Shaanxi, 710029, People's Republic of China.
| | - Yong Xu
- School of Natural and Applied Sciences, Department of Applied Mathematics, Northwestern Polytechnical University, Xi'an, Shaanxi, 710029, People's Republic of China
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29
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Romanò F, Muradoglu M, Fujioka H, Grotberg JB. The effect of viscoelasticity in an airway closure model. JOURNAL OF FLUID MECHANICS 2021; 913:A31. [PMID: 33776140 PMCID: PMC7996000 DOI: 10.1017/jfm.2020.1162] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The closure of a human lung airway is modeled as a pipe coated internally with a liquid that takes into account the viscoelastic properties of mucus. For a thick enough coating, the Plateau-Rayleigh instability blocks the airway by the creation of a liquid plug, and the pre-closure phase is dominated by the Newtonian behavior of the liquid. Our previous study with a Newtonian-liquid model demonstrated that the bifrontal plug growth consequent to airway closure induces a high level of stress and stress gradients on the airway wall, which is large enough to damage the epithelial cells, causing sub-lethal or lethal responses. In this study, we explore the effect of the viscoelastic properties of mucus by means of the Oldroyd-B and FENE-CR model. Viscoelasticity is shown to be very relevant in the post-coalescence process, introducing a second peak of the wall shear stresses. This second peak is related to an elastic instability due to the presence of the polymeric extra stresses. For high-enough Weissenberg and Laplace numbers, this second shear stress peak is as severe as the first one. Consequently, a second lethal or sub-lethal response of the epithelial cells is induced.
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Affiliation(s)
- F. Romanò
- Univ. Lille, CNRS, ONERA, Arts et Métiers Institute of Technology, Centrale Lille, UMR 9014 - LMFL - Laboratoire de Mécanique des Fluides de Lille - Kampé de Fériet, F-59000, Lille, France
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - M. Muradoglu
- Department of Mechanical Engineering, Koc University, Istanbul, Turkey
| | - H. Fujioka
- Center for Computational Science, Tulane University, New Orleans, LA, 70118, USA
| | - J. B. Grotberg
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
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30
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Khoa ND, Phuong NL, Tani K, Inthavong K, Ito K. Computational fluid dynamics comparison of impaired breathing function in French bulldogs with nostril stenosis and an examination of the efficacy of rhinoplasty. Comput Biol Med 2021; 134:104398. [PMID: 33905990 DOI: 10.1016/j.compbiomed.2021.104398] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/12/2021] [Accepted: 04/12/2021] [Indexed: 11/26/2022]
Abstract
BACKGROUND Brachycephalic obstructive airway syndrome (BOAS) in dogs indicates a particular set of upper airway abnormalities found in brachycephalic dogs (e.g., French bulldogs). Stenotic nares is one of the primary BOAS-related abnormalities restricting the functional breathing of affected dogs. For severe stenosis, rhinoplasty is required to increase the accessibility of the external nostril to air; however, the specific improvement from surgery in terms of respiratory physiology and uptake of inhaled air has not been fully elucidated METHOD: This study employed Computational Fluid Dynamics (CFD) simulations to evaluate the effects of different stenotic intensities on airflow patterns in a total of eight French bulldog upper airways. A bulldog with severe stenosis after surgery was included to examine the efficacy of the surgical intervention. RESULTS The results showed homogeneous airflow distributions in healthy and mild stenosis cases and significantly accelerated airstreams at the constricted positions in moderate and severe stenosis bulldogs. The airflow resistance was over 20-fold greater in severe stenosis cases than the healthy cases. After surgery, a decrease in airflow velocity was observed in the surgical region, and the percentage of reduced airflow resistance was approximately 4%. CONCLUSIONS This study suggests impaired breathing function in brachycephalic dogs with moderate and severe stenosis. The results also serve as a reference for veterinarians in surgical planning and monitoring bulldogs' recuperation after surgery.
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Affiliation(s)
- Nguyen Dang Khoa
- Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka, 816-8580, Japan.
| | - Nguyen Lu Phuong
- Faculty of Environment, Ho Chi Minh City University of Natural Resources and Environment, 236 Le Van Sy, Ward 1, Tan Binh district, Ho Chi Minh City, Viet Nam
| | - Kenji Tani
- Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yda, Yamaguchi Cityoshi, Yamaguchi, 753-8511, Japan
| | - Kiao Inthavong
- School of Engineering, Mechanical & Automotive, RMIT University, GPO Box 2476, Melbourne, VIC, 3001, Australia
| | - Kazuhide Ito
- Faculty of Engineering Sciences, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka, 816-8580, Japan
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Pertile J, Smith B, Mellenthin M, Wagner J, DeBoer EM, Fink DS. Jet flow rate and needle position govern distal airway pressures during low-frequency jet ventilation. Laryngoscope Investig Otolaryngol 2021; 6:244-251. [PMID: 33869756 PMCID: PMC8035948 DOI: 10.1002/lio2.536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 12/02/2020] [Accepted: 01/27/2021] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVES Although jet ventilation is frequently used during surgery for airway stenosis, little is known about distal airway pressures during jet ventilation. The objective of the study is to determine how jet pressure, flow rate, and position of the ventilation needle relate to distal airway pressure magnitude and homogeneity. METHODS Two 3D models of the first five generations of the human airway tree were created. One is a duplicate of a human airway from a 15-year-old healthy male's computed tomography scan, and the other is an idealized symmetric model of human lung morphometry. Pressure transducers measured fifth-generation distal airway pressures in both models. A computer-controlled jet needle positioning system was used to ventilate the lung casts. The effects of jet needle position, jet pressure, and jet flow rate on distal airway pressure and homogeneity were measured. RESULTS Total entrained jet flow rate was the most reliable predictor of distal airway pressure. Pressure supplied to the jet ventilation needle had a positive linear relationship with distal airway pressure; however, this relationship was dependent on the jet needle flow resistance. As the ventilation needle moved closer to the tracheal wall, ventilation homogeneity decreased. Depth into the trachea was positively correlated with sensitivity of the needle to the tracheal wall. CONCLUSION In this model, total entrained jet flow rate is a more robust predictor of distal airway pressure than jet inlet pressure. More homogeneous ventilation was observed in our model with the ventilation needle centered in the proximal region of the trachea.
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Affiliation(s)
- Joshua Pertile
- Department of BioengineeringUniversity of Colorado DenverAnschutz Medical CampusAuroraColoradoUSA
| | - Bradford Smith
- Department of BioengineeringUniversity of Colorado DenverAnschutz Medical CampusAuroraColoradoUSA
- Department of Pediatrics, School of MedicineUniversity of ColoradoAuroraColoradoUSA
| | - Michelle Mellenthin
- Department of BioengineeringUniversity of Colorado DenverAnschutz Medical CampusAuroraColoradoUSA
- Department of Computer Science and EngineeringColorado Mesa UniversityGrand JunctionColoradoUSA
| | - Jennifer Wagner
- Department of BioengineeringUniversity of Colorado DenverAnschutz Medical CampusAuroraColoradoUSA
| | - Emily M. DeBoer
- Department of Pediatrics, School of MedicineUniversity of ColoradoAuroraColoradoUSA
| | - Daniel S. Fink
- Department of Otolaryngology, School of MedicineUniversity of ColoradoAuroraColoradoUSA
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Hsieh PC, Kuo CY, Wu CP, Yue CT, Peng CK, Huang KL, Lan CC. Nonionic surfactant attenuates acute lung injury by restoring epithelial integrity and alveolar fluid clearance. Int J Med Sci 2021; 18:1363-1374. [PMID: 33628092 PMCID: PMC7893557 DOI: 10.7150/ijms.51905] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 01/06/2021] [Indexed: 01/09/2023] Open
Abstract
Introduction: Acute lung injury (ALI) has a great impact and a high mortality rate in intensive care units (ICUs). Excessive air may enter the lungs, causing pulmonary air embolism (AE)-induced ALI. Some invasive iatrogenic procedures cause pulmonary AE-induced ALI, with the presentation of severe inflammatory reactions, hypoxia, and pulmonary hypertension. Pulmonary surfactants are vital in the lungs to reduce the surface tension and inflammation. Nonionic surfactants (NIS) are a kind of surfactants without electric charge on their hydrophilic parts. Studies on NIS in AE-induced ALI are limited. We aimed to study the protective effects and mechanisms of NIS in AE-induced ALI. Materials and methods: Five different groups (n = 6 in each group) were created: sham, AE, AE + NIS pretreatment (0.5 mg/kg), AE + NIS pretreatment (1 mg/kg), and AE + post-AE NIS (1 mg/kg). AE-induced ALI was introduced by the infusion of air via the pulmonary artery. Aerosolized NIS were administered via tracheostomy. Results: Pulmonary AE-induced ALI showed destruction of the alveolar cell integrity with increased pulmonary microvascular permeability, pulmonary vascular resistance, pulmonary edema, and lung inflammation. The activation of nuclear factor-κB (NF-κB) increased the expression of pro-inflammatory cytokines, and sodium-potassium-chloride co-transporter isoform 1 (NKCC1). The pretreatment with NIS (1 mg/kg) prominently maintained the integrity of the epithelial lining and suppressed the expression of NF-κB, pro-inflammatory cytokines, and NKCC1, subsequently reducing AE-induced ALI. Conclusions: NIS maintained the integrity of the epithelial lining and suppressed the expression of NF-κB, pro-inflammatory cytokines, and NKCC1, thereby reducing hyperpermeability, pulmonary edema, and inflammation in ALI.
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Affiliation(s)
- Po-Chun Hsieh
- Department of Chinese Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Chan-Yen Kuo
- Department of Research, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan
| | - Chin-Pyng Wu
- Department of Critical Care Medicine, Landseed International Hospital, Tao-Yuan City, Taiwan
| | - Chung-Tai Yue
- Department of Anatomic Pathology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei City, Taiwan; Department of Pathology, Buddhist Tzu Chi University, Hualien, Taiwan
| | - Chung-Kan Peng
- Division of Pulmonary Medicine, Tri-Service General Hospital, Taipei, Taiwan; Institute of Undersea and Hyperbaric Medicine, National Defense Medical Center, Taipei, Taiwan
| | - Kun-Lun Huang
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
- Division of Pulmonary Medicine, Tri-Service General Hospital, Taipei, Taiwan; Institute of Undersea and Hyperbaric Medicine, National Defense Medical Center, Taipei, Taiwan
| | - Chou-Chin Lan
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
- Division of Pulmonary Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation; School of Medicine, Tzu-Chi University, Hualien, Taiwan
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Abstract
Bronchopulmonary dysplasia (BPD) is among the most severe complications of very premature birth. Clinical and laboratory studies indicate that lung immaturity, inflammatory lung injury, and disordered lung repair are the primary mechanisms responsible for the development of BPD. Caffeine, initiated within the first 10 days after birth, is one of few drug therapies shown to significantly decrease the risk of BPD in very low birth weight infants. This benefit is likely derived, at least in part, from reduced exposure to positive airway pressure and supplemental oxygen with caffeine therapy. Additional cardiorespiratory benefits of caffeine that may contribute to the lower risk of BPD include less frequent treatment for a PDA, improved pulmonary mechanics, and direct effects on pulmonary inflammation, alveolarization, and angiogenesis. Routine administration of caffeine is indicated in the vast majority of very low birth weight infants. However, current preventative strategies including widespread use of caffeine do not avert BPD in all cases. As such, there is continued need for novel methods to further reduce the risk of BPD in very low birth weight infants.
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Affiliation(s)
- Erik A Jensen
- Division of Neonatology and Department of Pediatrics, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA, United States.
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Abstract
PURPOSE OF REVIEW Most clinical trials of lung-protective ventilation have tested one-size-fits-all strategies with mixed results. Data are lacking on how best to tailor mechanical ventilation to patient-specific risk of lung injury. RECENT FINDINGS Risk of ventilation-induced lung injury is determined by biological predisposition to biophysical lung injury and physical mechanical perturbations that concentrate stress and strain regionally within the lung. Recent investigations have identified molecular subphenotypes classified as hyperinflammatory and hypoinflammatory acute respiratory distress syndrome (ARDS), which may have dissimilar risk for ventilation-induced lung injury. Mechanically, gravity-dependent atelectasis has long been recognized to decrease total aerated lung volume available for tidal ventilation, a concept termed the 'ARDS baby lung'. Recent studies have demonstrated that the aerated baby lung also has nonuniform stress/strain distribution, with potentially injurious forces concentrated in zones of heterogeneity where aerated alveoli are adjacent to flooded or atelectatic alveoli. The preponderance of evidence also indicates that current standard-of-care tidal volume management is not universally protective in ARDS. When considering escalation of lung-protective interventions, potential benefits of the intervention should be weighed against tradeoffs of accompanying cointerventions required, for example, deeper sedation or neuromuscular blockade. A precision medicine approach to lung-protection would weigh. SUMMARY A precision medicine approach to lung-protective ventilation requires weighing four key factors in each patient: biological predisposition to biophysical lung injury, mechanical predisposition to biophysical injury accounting for spatial mechanical heterogeneity within the lung, anticipated benefits of escalating lung-protective interventions, and potential unintended adverse effects of mandatory cointerventions.
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Wu Y, Nguyen TL, Perlman CE. Intravenous sulforhodamine B reduces alveolar surface tension, improves oxygenation, and reduces ventilation injury in a respiratory distress model. J Appl Physiol (1985) 2020; 130:1305-1316. [PMID: 33211596 DOI: 10.1152/japplphysiol.00421.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In the neonatal respiratory distress syndrome (NRDS) and acute respiratory distress syndrome (ARDS), mechanical ventilation supports gas exchange but can cause ventilation-induced lung injury (VILI) that contributes to high mortality. Further, surface tension, T, should be elevated and VILI is proportional to T. Surfactant therapy is effective in NRDS but not ARDS. Sulforhodamine B (SRB) is a potential alternative T-lowering therapeutic. In anesthetized male rats, we injure the lungs with 15 min of 42 mL/kg tidal volume, VT, and zero end-expiratory pressure ventilation. Then, over 4 h, we support the rats with protective ventilation-VT of 6 mL/kg with positive end-expiratory pressure. At the start of the support period, we administer intravenous non-T-altering fluorescein (targeting 27 µM in plasma) without or with therapeutic SRB (10 nM). Throughout the support period, we increase inspired oxygen fraction, as necessary, to maintain >90% arterial oxygen saturation. At the end of the support period, we euthanize the rat; sample systemic venous blood for injury marker ELISAs; excise the lungs; combine confocal microscopy and servo-nulling pressure measurement to determine T in situ in the lungs; image fluorescein in alveolar liquid to assess local permeability; and determine lavage protein content and wet-to-dry ratio (W/D) to assess global permeability. Lungs exhibit focal injury. Surface tension is elevated 72% throughout control lungs and in uninjured regions of SRB-treated lungs, but normal in injured regions of treated lungs. SRB administration improves oxygenation, reduces W/D, and reduces plasma injury markers. Intravenous SRB holds promise as a therapy for respiratory distress.NEW & NOTEWORTHY Sulforhodmaine B lowers T in alveolar edema liquid. Given the problematic intratracheal delivery of surfactant therapy for ARDS, intravenous SRB might constitute an alternative therapeutic. In a lung injury model, we find that intravenously administered SRB crosses the injured alveolar-capillary barrier thus reduces T specifically in injured lung regions; improves oxygenation; and reduces the degree of further lung injury. Intravenous SRB administration might help respiratory distress patients, including those with the novel coronavirus, avoid mechanical ventilation or, once ventilated, survive.
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Affiliation(s)
- You Wu
- Department of Biomedical Engineering, Stevens Institute of Technology, Hoboken, New Jersey
| | - Tam L Nguyen
- Department of Biomedical Engineering, Stevens Institute of Technology, Hoboken, New Jersey
| | - Carrie E Perlman
- Department of Biomedical Engineering, Stevens Institute of Technology, Hoboken, New Jersey
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36
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Gaver DP, Nieman GF, Gatto LA, Cereda M, Habashi NM, Bates JHT. The POOR Get POORer: A Hypothesis for the Pathogenesis of Ventilator-induced Lung Injury. Am J Respir Crit Care Med 2020; 202:1081-1087. [PMID: 33054329 DOI: 10.1164/rccm.202002-0453cp] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Protective ventilation strategies for the injured lung currently revolve around the use of low Vt, ostensibly to avoid volutrauma, together with positive end-expiratory pressure to increase the fraction of open lung and reduce atelectrauma. Protective ventilation is currently applied in a one-size-fits-all manner, and although this practical approach has reduced acute respiratory distress syndrome deaths, mortality is still high and improvements are at a standstill. Furthermore, how to minimize ventilator-induced lung injury (VILI) for any given lung remains controversial and poorly understood. Here we present a hypothesis of VILI pathogenesis that potentially serves as a basis upon which minimally injurious ventilation strategies might be developed. This hypothesis is based on evidence demonstrating that VILI begins in isolated lung regions manifesting a Permeability-Originated Obstruction Response (POOR) in which alveolar leak leads to surfactant dysfunction and increases local tissue stresses. VILI progresses topographically outward from these regions in a POOR-get-POORer fashion unless steps are taken to interrupt it. We propose that interrupting the POOR-get-POORer progression of lung injury relies on two principles: 1) open the lung to minimize the presence of heterogeneity-induced stress concentrators that are focused around the regions of atelectasis, and 2) ventilate in a patient-dependent manner that minimizes the number of lung units that close during each expiration so that they are not forced to rerecruit during the subsequent inspiration. These principles appear to be borne out in both patient and animal studies in which expiration is terminated before derecruitment of lung units has enough time to occur.
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Affiliation(s)
- Donald P Gaver
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
| | - Gary F Nieman
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York
| | - Louis A Gatto
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York
| | - Maurizio Cereda
- Department of Anesthesiology and Critical Care and.,Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Nader M Habashi
- R Adams Cowley Shock Trauma Center, University of Maryland, Baltimore, Maryland; and
| | - Jason H T Bates
- Department of Medicine, University of Vermont, Burlington, Vermont
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37
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Pertile J, Mellenthin M, Wagner J, DeBoer EM, Fink D, Smith B. The Effects of Laryngoscope Shape and Needle Position on Distal Airway Pressure in Jet Ventilation. Laryngoscope 2020; 131:E354-E357. [PMID: 32717125 DOI: 10.1002/lary.28923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/29/2020] [Accepted: 06/18/2020] [Indexed: 11/08/2022]
Abstract
OBJECTIVES Laryngoscopes and subglottiscopes of multiple shapes and lengths are used in airway surgery to maintain an open airway; protect the trachea; and provide a place to mount the light, evacuator, and ventilation needle. Despite differences in scopes and ventilation needle mounting positions, the same jet pressures are typically used. We hypothesized that different scopes and scope configurations would affect distal airway pressure magnitude and homogeneity. STUDY DESIGN A laboratory investigation of distal airway pressures in a lung modelduring low frequency jet ventilation. METHODS A three-dimensional airway model based on the computed tomography scan of a 15-year old healthy male was fabricated with pressure transducers at the fifth airway generation. A laryngoscope and a subglottiscope were each mounted in the model coaxial with the trachea. Parameters including scope depth and needle mounting position were adjusted, and the effects on distal airway pressure were recorded. RESULTS Changing the scope depth from 1 to 3 cm past the laryngeal inlet had a limited effect on distal airway pressure. Needle mounting angle in the laryngoscope strongly influenced distal airway pressure, with a 7° angle change yielding a 67.5% increase. Compared to a loose needle centered in the trachea 1 cm past the laryngeal inlet, the subglottiscope and laryngoscope showed up to 16% and 150% increases in distal airway pressure, respectively. CONCLUSION Different scopes or changes in the configuration, such as the needle angle, strongly influence distal airway pressure. Our findings indicate that different jet pressures are required for different scopes and that a stable needle mount is a critical design consideration to prevent changes in minute ventilation due to needle movement. LEVEL OF EVIDENCE NA (Basic Research) Laryngoscope, 131:E354-E357, 2021.
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Affiliation(s)
- Joshua Pertile
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado, U.S.A.,Department of Computer Science and Engineering, Colorado Mesa University, Grand Junction, Colorado, U.S.A
| | - Michelle Mellenthin
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado, U.S.A.,Department of Computer Science and Engineering, Colorado Mesa University, Grand Junction, Colorado, U.S.A
| | - Jennifer Wagner
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado, U.S.A
| | - Emily M DeBoer
- Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, U.S.A
| | - Daniel Fink
- Department of Otolaryngology, School of Medicine, University of Colorado, Aurora, Colorado, U.S.A
| | - Bradford Smith
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado, U.S.A.,Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, U.S.A
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38
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Munir B, Xu Y. Effects of gravity and surface tension on steady microbubble propagation in asymmetric bifurcating airways. PHYSICS OF FLUIDS (WOODBURY, N.Y. : 1994) 2020; 32:072105. [PMID: 35002196 PMCID: PMC8722330 DOI: 10.1063/5.0012796] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 07/03/2020] [Indexed: 05/21/2023]
Abstract
Mechanical ventilation is nowadays a well-developed, safe, and necessary strategy for acute respiratory distress syndrome patients to survive. However, the propagation of microbubbles in airway bifurcations during mechanical ventilation makes the existing lung injury more severe. In this paper, finite element and direct interface tracking techniques were utilized to simulate steady microbubble propagation in a two-dimensional asymmetric bifurcating airway filled with a viscous fluid. Inertial effects were neglected, and the numerical solution of Stokes's equations was used to investigate how gravity and surface tension defined by a Bond (Bo) number and capillary (Ca) number influence the magnitudes of pressure gradients, shear stresses, and shear stress gradients on the bifurcating daughter airway wall. It is found that increasing Bo significantly influenced both the bubble shape and hydrodynamic stresses, where Bo ≥ 0.25 results in a significant increase in bubble elevation and pressure gradient in the upper daughter wall. Although for both Bo and Ca, the magnitude of the pressure gradient is always much larger in the upper daughter airway wall, Ca has a great role in amplifying the magnitude of the pressure gradient. In conclusion, both gravity and surface tension play a key role in the steady microbubble propagation and hydrodynamic stresses in the bifurcating airways.
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Affiliation(s)
- Bacha Munir
- Author to whom correspondence should be addressed:
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39
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Radiom M, He Y, Peng-Wang J, Baeza-Squiban A, Berret JF, Chen Y. Alveolar mimics with periodic strain and its effect on the cell layer formation. Biotechnol Bioeng 2020; 117:2827-2841. [PMID: 32542664 DOI: 10.1002/bit.27458] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/09/2020] [Accepted: 06/13/2020] [Indexed: 12/16/2022]
Abstract
We report on the development of a new model of alveolar air-tissue interface on a chip. The model consists of an array of suspended hexagonal monolayers of gelatin nanofibers supported by microframes and a microfluidic device for the patch integration. The suspended monolayers are deformed to a central displacement of 40-80 µm at the air-liquid interface by application of air pressure in the range of 200-1,000 Pa. With respect to the diameter of the monolayers, that is, 500 µm, this displacement corresponds to a linear strain of 2-10% in agreement with the physiological strain range in the lung alveoli. The culture of A549 cells on the monolayers for an incubation time of 1-3 days showed viability in the model. We exerted a periodic strain of 5% at a frequency of 0.2 Hz for 1 hr to the cells. We found that the cells were strongly coupled to the nanofibers, but the strain reduced the coupling and induced remodeling of the actin cytoskeleton, which led to a better tissue formation. Our model can serve as a versatile tool in lung investigations such as in inhalation toxicology and therapy.
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Affiliation(s)
- Milad Radiom
- Laboratoire Matière et Systèmes Complexes, CNRS UMR 7057, Université Paris Diderot Paris-VII, Paris, France
| | - Yong He
- Département de Chimie, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640, Pasteur, École Normale Supérieure-PSL Research University, Paris, France
| | - Juan Peng-Wang
- Département de Chimie, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640, Pasteur, École Normale Supérieure-PSL Research University, Paris, France
| | - Armelle Baeza-Squiban
- Unité de Biologie Fonctionnelle et Adaptative, CNRS UMR 8251, Université Paris Diderot Paris-VII, Paris, France
| | - Jean-François Berret
- Laboratoire Matière et Systèmes Complexes, CNRS UMR 7057, Université Paris Diderot Paris-VII, Paris, France
| | - Yong Chen
- Département de Chimie, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640, Pasteur, École Normale Supérieure-PSL Research University, Paris, France
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40
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Perlman CE. The Contribution of Surface Tension-Dependent Alveolar Septal Stress Concentrations to Ventilation-Induced Lung Injury in the Acute Respiratory Distress Syndrome. Front Physiol 2020; 11:388. [PMID: 32670073 PMCID: PMC7332732 DOI: 10.3389/fphys.2020.00388] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/01/2020] [Indexed: 01/22/2023] Open
Abstract
In the acute respiratory distress syndrome (ARDS), surface tension, T, is likely elevated. And mechanical ventilation of ARDS patients causes ventilation-induced lung injury (VILI), which is believed to be proportional to T. However, the mechanisms through which elevated T may contribute to VILI have been under-studied. This conceptual analysis considers experimental and theoretical evidence for static and dynamic mechanical mechanisms, at the alveolar scale, through which elevated T exacerbates VILI; potential causes of elevated T in ARDS; and T-dependent means of reducing VILI. In the last section, possible means of reducing T and improving the efficacy of recruitment maneuvers during mechanical ventilation of ARDS patients are discussed.
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Affiliation(s)
- Carrie E Perlman
- Department of Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ, United States
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41
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Hu Y, Romanò F, Grotberg JB. Effects of Surface Tension and Yield Stress on Mucus Plug Rupture: A Numerical Study. J Biomech Eng 2020; 142:061007. [PMID: 31802106 PMCID: PMC7104762 DOI: 10.1115/1.4045596] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/01/2019] [Indexed: 12/12/2022]
Abstract
We study the effects of surface tension and yield stress on mucus plug rupture. A three-dimensional simplified configuration is employed to simulate mucus plug rupture in a collapsed lung airway of the tenth generation. The Herschel-Bulkley model is used to take into account the non-Newtonian viscoplastic fluid properties of mucus. Results show that the maximum wall shear stress greatly changes right prior to the rupture of the mucus plug. The surface tension influences mainly the late stage of the rupture process when the plug deforms greatly and the curvature of the mucus-air interface becomes significant. High surface tension increases the wall shear stress and the time needed to rupture since it produces a resistance to the rupture, as well as strong stress and velocity gradients across the mucus-air interface. The yield stress effects are pronounced mainly at the beginning. High yield stress makes the plug take a long time to yield and slows down the whole rupture process. When the effects induced by the surface tension and yield forces are comparable, dynamical quantities strongly depend on the ratio of the two forces. The pressure difference (the only driving in the study) contributes to wall shear stress much more than yield stress and surface tension per unit length. Wall shear stress is less sensitive to the variation in yield stress than that in surface tension. In general, wall shear stress can be effectively reduced by the smaller pressure difference and surface tension.
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Affiliation(s)
- Yingying Hu
- School of Electrical and Power Engineering, China University
of Mining and Technology, Xuzhou, Jiangsu
221116, China
e-mail:
| | - Francesco Romanò
- Department of Biomedical Engineering, University of
Michigan, 2123 Carl A. Gerstacker
Building,2200 Bonisteel Boulevard, Ann Arbor, MI
48109-2099; FRE 2017-LMFL-Laboratoire de Mécanique
des Fluides de Lille-Kampé de Fériet, Centrale Lille, Arts
et Metiers ParisTech, ONERA, CNRS, University
Lille, Lille F-59000,
France
| | - James B. Grotberg
- Department of Biomedical Engineering, University of
Michigan, 2123 Carl A. Gerstacker Building,
2200 Bonisteel Boulevard, Ann Arbor, MI
48109-2099
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42
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Sehlmeyer K, Ruwisch J, Roldan N, Lopez-Rodriguez E. Alveolar Dynamics and Beyond - The Importance of Surfactant Protein C and Cholesterol in Lung Homeostasis and Fibrosis. Front Physiol 2020; 11:386. [PMID: 32431623 PMCID: PMC7213507 DOI: 10.3389/fphys.2020.00386] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 03/30/2020] [Indexed: 12/13/2022] Open
Abstract
Surfactant protein C (SP-C) is an important player in enhancing the interfacial adsorption of lung surfactant lipid films to the alveolar air-liquid interface. Doing so, surface tension drops down enough to stabilize alveoli and the lung, reducing the work of breathing. In addition, it has been shown that SP-C counteracts the deleterious effect of high amounts of cholesterol in the surfactant lipid films. On its side, cholesterol is a well-known modulator of the biophysical properties of biological membranes and it has been proven that it activates the inflammasome pathways in the lung. Even though the molecular mechanism is not known, there are evidences suggesting that these two molecules may interplay with each other in order to keep the proper function of the lung. This review focuses in the role of SP-C and cholesterol in the development of lung fibrosis and the potential pathways in which impairment of both molecules leads to aberrant lung repair, and therefore impaired alveolar dynamics. From molecular to cellular mechanisms to evidences in animal models and human diseases. The evidences revised here highlight a potential SP-C/cholesterol axis as target for the treatment of lung fibrosis.
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Affiliation(s)
- Kirsten Sehlmeyer
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Centre for Lung Research, Hanover, Germany
| | - Jannik Ruwisch
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Centre for Lung Research, Hanover, Germany
| | - Nuria Roldan
- Alveolix AG and ARTORG Center, University of Bern, Bern, Switzerland
| | - Elena Lopez-Rodriguez
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Centre for Lung Research, Hanover, Germany
- Institute of Functional Anatomy, Charité – Universitätsmedizin Berlin, Berlin, Germany
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43
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Matuszak J, Tabuchi A, Kuebler WM. Ventilation and Perfusion at the Alveolar Level: Insights From Lung Intravital Microscopy. Front Physiol 2020; 11:291. [PMID: 32308629 PMCID: PMC7145899 DOI: 10.3389/fphys.2020.00291] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 03/16/2020] [Indexed: 01/13/2023] Open
Abstract
Intravital microscopy (IVM) offers unique possibilities for the observation of biological processes and disease related mechanisms in vivo. Especially for anatomically complex and dynamic organs such as the lung and its main functional unit, the alveolus, IVM provides exclusive advantages in terms of spatial and temporal resolution. By the use of lung windows, which have advanced and improved over time, direct access to the lung surface is provided. In this review we will discuss two main topics, namely alveolar dynamics and perfusion from the perspective of IVM-based studies. Of special interest are unanswered questions regarding alveolar dynamics such as: What are physiologic alveolar dynamics? How do these dynamics change under pathologic conditions and how do those changes contribute to ventilator-induced lung injury? How can alveolar dynamics be targeted in a beneficial way? With respect to alveolar perfusion IVM has propelled our understanding of the pulmonary microcirculation and its perfusion, as well as pulmonary vasoreactivity, permeability and immunological aspects. Whereas the general mechanism behind these processes are understood, we still lack a proper understanding of the complex, multidimensional interplay between alveolar ventilation and microvascular perfusion, capillary recruitment, or vascular immune responses under physiologic and pathologic conditions. These are only part of the unanswered questions and problems, which we still have to overcome. IVM as the tool of choice might allow us to answer part of these questions within the next years or decades. As every method, IVM has advantages as well as limitations, which have to be taken into account for data analysis and interpretation, which will be addressed in this review.
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Affiliation(s)
- Jasmin Matuszak
- Institute of Physiology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Arata Tabuchi
- The Keenan Research Centre for Biomedical Science at St. Michael’s, Toronto, ON, Canada
| | - Wolfgang M. Kuebler
- Institute of Physiology, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
- Departments of Surgery and Physiology, University of Toronto, Toronto, ON, Canada
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44
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Abstract
Ventilation-induced lung injury results from mechanical stress and strain that occur during tidal ventilation in the susceptible lung. Classical descriptions of ventilation-induced lung injury have focused on harm from positive pressure ventilation. However, injurious forces also can be generated by patient effort and patient–ventilator interactions. While the role of global mechanics has long been recognized, regional mechanical heterogeneity within the lungs also appears to be an important factor propagating clinically significant lung injury. The resulting clinical phenotype includes worsening lung injury and a systemic inflammatory response that drives extrapulmonary organ failures. Bedside recognition of ventilation-induced lung injury requires a high degree of clinical acuity given its indistinct presentation and lack of definitive diagnostics. Yet the clinical importance of ventilation-induced lung injury is clear. Preventing such biophysical injury remains the most effective management strategy to decrease morbidity and mortality in patients with acute respiratory distress syndrome and likely benefits others at risk.
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Affiliation(s)
- Purnema Madahar
- Center for Acute Respiratory Failure, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Department of Medicine, New York-Presbyterian Hospital, New York City, NY, USA
| | - Jeremy R Beitler
- Center for Acute Respiratory Failure, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Department of Medicine, New York-Presbyterian Hospital, New York City, NY, USA
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45
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Nieman GF, Al-Khalisy H, Kollisch-Singule M, Satalin J, Blair S, Trikha G, Andrews P, Madden M, Gatto LA, Habashi NM. A Physiologically Informed Strategy to Effectively Open, Stabilize, and Protect the Acutely Injured Lung. Front Physiol 2020; 11:227. [PMID: 32265734 PMCID: PMC7096584 DOI: 10.3389/fphys.2020.00227] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/27/2020] [Indexed: 12/16/2022] Open
Abstract
Acute respiratory distress syndrome (ARDS) causes a heterogeneous lung injury and remains a serious medical problem, with one of the only treatments being supportive care in the form of mechanical ventilation. It is very difficult, however, to mechanically ventilate the heterogeneously damaged lung without causing secondary ventilator-induced lung injury (VILI). The acutely injured lung becomes time and pressure dependent, meaning that it takes more time and pressure to open the lung, and it recollapses more quickly and at higher pressure. Current protective ventilation strategies, ARDSnet low tidal volume (LVt) and the open lung approach (OLA), have been unsuccessful at further reducing ARDS mortality. We postulate that this is because the LVt strategy is constrained to ventilating a lung with a heterogeneous mix of normal and focalized injured tissue, and the OLA, although designed to fully open and stabilize the lung, is often unsuccessful at doing so. In this review we analyzed the pathophysiology of ARDS that renders the lung susceptible to VILI. We also analyzed the alterations in alveolar and alveolar duct mechanics that occur in the acutely injured lung and discussed how these alterations are a key mechanism driving VILI. Our analysis suggests that the time component of each mechanical breath, at both inspiration and expiration, is critical to normalize alveolar mechanics and protect the lung from VILI. Animal studies and a meta-analysis have suggested that the time-controlled adaptive ventilation (TCAV) method, using the airway pressure release ventilation mode, eliminates the constraints of ventilating a lung with heterogeneous injury, since it is highly effective at opening and stabilizing the time- and pressure-dependent lung. In animal studies it has been shown that by “casting open” the acutely injured lung with TCAV we can (1) reestablish normal expiratory lung volume as assessed by direct observation of subpleural alveoli; (2) return normal parenchymal microanatomical structural support, known as alveolar interdependence and parenchymal tethering, as assessed by morphometric analysis of lung histology; (3) facilitate regeneration of normal surfactant function measured as increases in surfactant proteins A and B; and (4) significantly increase lung compliance, which reduces the pathologic impact of driving pressure and mechanical power at any given tidal volume.
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Affiliation(s)
- Gary F Nieman
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Hassan Al-Khalisy
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, United States.,Department of Medicine, SUNY Upstate Medical University, Syracuse, NY, United States
| | | | - Joshua Satalin
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Sarah Blair
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Girish Trikha
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, United States.,Department of Medicine, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Penny Andrews
- Department of Trauma Critical Care Medicine, R Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Maria Madden
- Department of Trauma Critical Care Medicine, R Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Louis A Gatto
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, United States.,Department of Biological Sciences, SUNY Cortland, Cortland, NY, United States
| | - Nader M Habashi
- Department of Trauma Critical Care Medicine, R Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, MD, United States
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46
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Dai C, Zhang Z, Lu Y, Shan G, Wang X, Zhao Q, Ru C, Sun Y. Robotic Manipulation of Deformable Cells for Orientation Control. IEEE T ROBOT 2020. [DOI: 10.1109/tro.2019.2946746] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Yen S, Preissner M, Bennett E, Dubsky S, Carnibella R, Murrie R, Fouras A, Dargaville PA, Zosky GR. Interaction between regional lung volumes and ventilator-induced lung injury in the normal and endotoxemic lung. Am J Physiol Lung Cell Mol Physiol 2020; 318:L494-L499. [PMID: 31940217 DOI: 10.1152/ajplung.00492.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Both overdistension and atelectasis contribute to lung injury and mortality during mechanical ventilation. It has been proposed that combinations of tidal volume and end-expiratory lung volume exist that minimize lung injury linked to mechanical ventilation. The aim of this study was to examine this at the regional level in the healthy and endotoxemic lung. Adult female BALB/c mice were injected intraperitoneally with 10 mg/kg lipopolysaccharide (LPS) in saline or with saline alone. Four hours later, mice were mechanically ventilated for 2 h. Regional specific end-expiratory volume (sEEV) and tidal volume (sVt) were measured at baseline and after 2 h of ventilation using dynamic high-resolution four-dimensional computed tomography images. The regional expression of inflammatory genes was quantified by quantitative PCR. There was a heterogenous response in regional sEEV whereby endotoxemia increased gas trapping at end-expiration in some lung regions. Within the healthy group, there was a relationship between sEEV, sVt, and the expression of Tnfa, where high Vt in combination with high EEV or very low EEV was associated with an increase in gene expression. In endotoxemia there was an association between low sEEV, particularly when this was combined with moderate sVt, and high expression of IL6. Our data suggest that preexisting systemic inflammation modifies the relationship between regional lung volumes and inflammation and that although optimum EEV-Vt combinations to minimize injury exist, further studies are required to identify the critical inflammatory mediators to assess and the effect of different injury types on the response.
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Affiliation(s)
- Seiha Yen
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Melissa Preissner
- Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, Victoria, Australia
| | - Ellen Bennett
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Stephen Dubsky
- Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, Victoria, Australia
| | | | - Rhiannon Murrie
- Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, Victoria, Australia
| | | | - Peter A Dargaville
- Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Graeme R Zosky
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia.,Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
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48
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Nieman GF, Gatto LA, Andrews P, Satalin J, Camporota L, Daxon B, Blair SJ, Al-Khalisy H, Madden M, Kollisch-Singule M, Aiash H, Habashi NM. Prevention and treatment of acute lung injury with time-controlled adaptive ventilation: physiologically informed modification of airway pressure release ventilation. Ann Intensive Care 2020; 10:3. [PMID: 31907704 PMCID: PMC6944723 DOI: 10.1186/s13613-019-0619-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 12/23/2019] [Indexed: 12/16/2022] Open
Abstract
Mortality in acute respiratory distress syndrome (ARDS) remains unacceptably high at approximately 39%. One of the only treatments is supportive: mechanical ventilation. However, improperly set mechanical ventilation can further increase the risk of death in patients with ARDS. Recent studies suggest that ventilation-induced lung injury (VILI) is caused by exaggerated regional lung strain, particularly in areas of alveolar instability subject to tidal recruitment/derecruitment and stress-multiplication. Thus, it is reasonable to expect that if a ventilation strategy can maintain stable lung inflation and homogeneity, regional dynamic strain would be reduced and VILI attenuated. A time-controlled adaptive ventilation (TCAV) method was developed to minimize dynamic alveolar strain by adjusting the delivered breath according to the mechanical characteristics of the lung. The goal of this review is to describe how the TCAV method impacts pathophysiology and protects lungs with, or at high risk of, acute lung injury. We present work from our group and others that identifies novel mechanisms of VILI in the alveolar microenvironment and demonstrates that the TCAV method can reduce VILI in translational animal ARDS models and mortality in surgical/trauma patients. Our TCAV method utilizes the airway pressure release ventilation (APRV) mode and is based on opening and collapsing time constants, which reflect the viscoelastic properties of the terminal airspaces. Time-controlled adaptive ventilation uses inspiratory and expiratory time to (1) gradually “nudge” alveoli and alveolar ducts open with an extended inspiratory duration and (2) prevent alveolar collapse using a brief (sub-second) expiratory duration that does not allow time for alveolar collapse. The new paradigm in TCAV is configuring each breath guided by the previous one, which achieves real-time titration of ventilator settings and minimizes instability induced tissue damage. This novel methodology changes the current approach to mechanical ventilation, from arbitrary to personalized and adaptive. The outcome of this approach is an open and stable lung with reduced regional strain and greater lung protection.
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Affiliation(s)
- Gary F Nieman
- Dept of Surgery, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA
| | - Louis A Gatto
- Dept of Surgery, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA
| | - Penny Andrews
- Multi-trauma Critical Care, R Adams Cowley Shock Trauma Center, University of Maryland Medical Center, 22 South Greene Street, Baltimore, MD, USA
| | - Joshua Satalin
- Dept of Surgery, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA.
| | - Luigi Camporota
- Department of Critical Care, Guy's and St, Thomas' NHS Foundation Trust, Westminster Bridge Rd, London, SE1 7EH, UK
| | - Benjamin Daxon
- Dept of Anesthesiology and Perioperative Medicine, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905, USA
| | - Sarah J Blair
- Dept of Surgery, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA
| | - Hassan Al-Khalisy
- Dept of Surgery, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA
| | - Maria Madden
- Multi-trauma Critical Care, R Adams Cowley Shock Trauma Center, University of Maryland Medical Center, 22 South Greene Street, Baltimore, MD, USA
| | | | - Hani Aiash
- Dept of Surgery, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA.,Department of Clinical Perfusion, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA
| | - Nader M Habashi
- Multi-trauma Critical Care, R Adams Cowley Shock Trauma Center, University of Maryland Medical Center, 22 South Greene Street, Baltimore, MD, USA
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49
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Szabari MV, Takahashi K, Feng Y, Locascio JJ, Chao W, Carter EA, Vidal Melo MF, Musch G. Relation between Respiratory Mechanics, Inflammation, and Survival in Experimental Mechanical Ventilation. Am J Respir Cell Mol Biol 2019; 60:179-188. [PMID: 30199644 DOI: 10.1165/rcmb.2018-0100oc] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Low-tidal volume (Vt) ventilation might protect healthy lungs from volutrauma but lead to inflammation resulting from other mechanisms, namely alveolar derecruitment and the ensuing alveolar collapse and tidal reexpansion. We hypothesized that the different mechanisms of low- and high-volume injury would be reflected in different mechanical properties being associated with development of pulmonary inflammation and mortality: an increase of hysteresis, reflecting progressive alveolar derecruitment, at low Vt; an increase of elastance, as a result of overdistension, at higher Vt. Mice were allocated to "protective" (6 ml/kg) or "injurious" (15-20 ml/kg) Vt groups and ventilated for 16 hours or until death. We measured elastance and hysteresis; pulmonary IL-6, IL-1β, and MIP-2 (macrophage inflammatory protein 2); wet-to-dry ratio; and blood gases. Survival was greater in the protective group (60%) than in the injurious group (25%). Nonsurvivors showed increased pulmonary cytokines, particularly in the injurious group, with the increase of elastance reflecting IL-6 concentration. Survivors instead showed only modest increases of cytokines, independent of Vt and unrelated to the increase of elastance. No single lung strain threshold could discriminate survivors from nonsurvivors. Hysteresis increased faster in the protective group, but, contrary to our hypothesis, its change was inversely related to the concentration of cytokines. In this model, significant mortality associated with pulmonary inflammation occurred even for strain values as low as about 0.8. Low Vt improved survival. The accompanying increase of hysteresis was not associated with greater inflammation.
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Affiliation(s)
- Margit V Szabari
- 1 Department of Anesthesia, Critical Care and Pain Medicine.,2 Department of Medicine
| | | | - Yan Feng
- 1 Department of Anesthesia, Critical Care and Pain Medicine.,4 Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| | | | - Wei Chao
- 1 Department of Anesthesia, Critical Care and Pain Medicine.,4 Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland; and
| | - Edward A Carter
- 6 Department of Pediatrics, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | | | - Guido Musch
- 1 Department of Anesthesia, Critical Care and Pain Medicine.,7 Department of Anesthesiology, Washington University in St. Louis, St. Louis, Missouri
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50
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Maia LDA, Fernandes MVS, Santos RS, Agra LC, Carvalho AC, Rocha NDN, Oliveira MV, Santos CL, Morales MM, Capelozzi VL, Souza SAL, Gutfilen B, Schultz MJ, Gama de Abreu M, Pelosi P, Silva PL, Rocco PRM. Effects of Protective Mechanical Ventilation With Different PEEP Levels on Alveolar Damage and Inflammation in a Model of Open Abdominal Surgery: A Randomized Study in Obese Versus Non-obese Rats. Front Physiol 2019; 10:1513. [PMID: 31920717 PMCID: PMC6930834 DOI: 10.3389/fphys.2019.01513] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Accepted: 12/02/2019] [Indexed: 11/22/2022] Open
Abstract
Intraoperative positive end-expiratory pressure (PEEP) has been proposed to restore lung volumes and improve respiratory function in obesity. However, the biological impact of different PEEP levels on the lungs in obesity remains unknown. We aimed to compare the effects of PEEP = 2 cmH2O versus PEEP = 6 cmH2O during ventilation with low tidal volumes on lung function, histology, and biological markers in obese and non-obese rats undergoing open abdominal surgery. Forty-two Wistar rats (21 obese, 21 non-obese) were anesthetized and tracheotomized, and laparotomy was performed with standardized bowel manipulation. Rats were randomly ventilated with protective tidal volume (7 ml/kg) at PEEP = 2 cmH2O or PEEP = 6 cmH2O for 4 h, after which they were euthanized. Lung mechanics and histology, alveolar epithelial cell integrity, and biological markers associated with pulmonary inflammation, alveolar stretch, extracellular matrix, and epithelial and endothelial cell damage were analyzed. In obese rats, PEEP = 6 cmH2O compared with PEEP = 2 cmH2O was associated with less alveolar collapse (p = 0.02). E-cadherin expression was not different between the two PEEP groups. Gene expressions of interleukin (IL)-6 (p = 0.01) and type III procollagen (p = 0.004), as well as protein levels of tumor necrosis factor-alpha (p = 0.016), were lower at PEEP = 6 cmH2O than at PEEP = 2 cmH2O. In non-obese animals, PEEP = 6 cmH2O compared with PEEP = 2 cmH2O led to increased hyperinflation, reduced e-cadherin (p = 0.04), and increased gene expression of IL-6 (p = 0.004) and protein levels of tumor necrosis factor-alpha (p-0.029), but no changes in fibrogenesis. In conclusion, PEEP = 6 cmH2O reduced lung damage and inflammation in an experimental model of mechanical ventilation for open abdominal surgery, but only in obese animals.
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Affiliation(s)
- Lígia de A Maia
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcos V S Fernandes
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Raquel S Santos
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Laís C Agra
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Anna Carolinna Carvalho
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nazareth de N Rocha
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Department of Physiology and Pharmacology, Biomedical Institute, Fluminense Federal University, Niterói, Brazil
| | - Milena V Oliveira
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Cíntia L Santos
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcelo M Morales
- Laboratory of Cellular and Molecular Physiology, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vera L Capelozzi
- Department of Pathology, School of Medicine, University of São Paulo, São Paulo, Brazil
| | - Sergio A L Souza
- Nuclear Medicine Service, Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Bianca Gutfilen
- Nuclear Medicine Service, Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcus J Schultz
- Department of Intensive Care, Laboratory of Experimental Intensive Care and Anesthesiology (L.E.I.C.A.), Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Marcelo Gama de Abreu
- Department of Anesthesiology and Intensive Care Therapy, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Dresden University of Technology, Dresden, Germany
| | - Paolo Pelosi
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy.,San Martino Policlinico Hospital, IRCCS for Oncology and Neurosciences, Genoa, Italy
| | - Pedro L Silva
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Patricia R M Rocco
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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