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Wachtendorf LJ, Ahrens E, Suleiman A, von Wedel D, Tartler TM, Rudolph MI, Redaelli S, Santer P, Munoz-Acuna R, Santarisi A, Calderon HN, Kiyatkin ME, Novack L, Talmor D, Eikermann M, Schaefer MS. The association between intraoperative low driving pressure ventilation and perioperative healthcare-associated costs: A retrospective multicenter cohort study. J Clin Anesth 2024; 98:111567. [PMID: 39191081 DOI: 10.1016/j.jclinane.2024.111567] [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: 02/09/2024] [Revised: 07/24/2024] [Accepted: 07/28/2024] [Indexed: 08/29/2024]
Abstract
STUDY OBJECTIVE A low dynamic driving pressure during mechanical ventilation for general anesthesia has been associated with a lower risk of postoperative respiratory complications (PRC), a key driver of healthcare costs. It is, however, unclear whether maintaining low driving pressure is clinically relevant to measure and contain costs. We hypothesized that a lower dynamic driving pressure is associated with lower costs. DESIGN Multicenter retrospective cohort study. SETTING Two academic healthcare networks in New York and Massachusetts, USA. PATIENTS 46,715 adult surgical patients undergoing general anesthesia for non-ambulatory (inpatient and same-day admission) surgery between 2016 and 2021. INTERVENTIONS The primary exposure was the median intraoperative dynamic driving pressure. MEASUREMENTS The primary outcome was direct perioperative healthcare-associated costs, which were matched with data from the Healthcare Cost and Utilization Project-National Inpatient Sample (HCUP-NIS) to report absolute differences in total costs in United States Dollars (US$). We assessed effect modification by patients' baseline risk of PRC (score for prediction of postoperative respiratory complications [SPORC] ≥ 7) and effect mediation by rates of PRC (including post-extubation saturation < 90%, re-intubation or non-invasive ventilation within 7 days) and other major complications. MAIN RESULTS The median intraoperative dynamic driving pressure was 17.2cmH2O (IQR 14.0-21.3cmH2O). In adjusted analyses, every 5cmH2O reduction in dynamic driving pressure was associated with a decrease of -0.7% in direct perioperative healthcare-associated costs (95%CI -1.3 to -0.1%; p = 0.020). When a dynamic driving pressure below 15cmH2O was maintained, -US$340 lower total perioperative healthcare-associated costs were observed (95%CI -US$546 to -US$132; p = 0.001). This association was limited to patients at high baseline risk of PRC (n = 4059; -US$1755;97.5%CI -US$2495 to -US$986; p < 0.001), where lower risks of PRC and other major complications mediated 10.7% and 7.2% of this association (p < 0.001 and p = 0.015, respectively). CONCLUSIONS Intraoperative mechanical ventilation targeting low dynamic driving pressures could be a relevant measure to reduce perioperative healthcare-associated costs in high-risk patients.
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Affiliation(s)
- Luca J Wachtendorf
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America.
| | - Elena Ahrens
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America.
| | - Aiman Suleiman
- Department of Anesthesia, Intensive Care and Pain Management, Faculty of Medicine, University of Jordan, Queen Rania St, Amman, 11942, Jordan; Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, 111 East 210(th) Street, Bronx, New York 10467, United States of America.
| | - Dario von Wedel
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America.
| | - Tim M Tartler
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America
| | - Maíra I Rudolph
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, 111 East 210(th) Street, Bronx, New York 10467, United States of America; Department of Anesthesiology and Intensive Care Medicine, University Hospital of Cologne, Kerpener Strasse 62, Cologne 50937, Germany.
| | - Simone Redaelli
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America; School of Medicine and Surgery, University of Milano-Bicocca, Piazza dell'Ateneo Nuovo, 1, 20126 Milan, Italy.
| | - Peter Santer
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America.
| | - Ricardo Munoz-Acuna
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America.
| | - Abeer Santarisi
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, 111 East 210(th) Street, Bronx, New York 10467, United States of America; Department of Accident and Emergency Medicine, Jordan University Hospital, Queen Rania St, Amman 11942, Jordan.
| | - Harold N Calderon
- Department of Finance, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215, United States of America.
| | - Michael E Kiyatkin
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, 111 East 210(th) Street, Bronx, New York 10467, United States of America.
| | - Lena Novack
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America.
| | - Daniel Talmor
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America.
| | - Matthias Eikermann
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, 111 East 210(th) Street, Bronx, New York 10467, United States of America; Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen, Hufelandstraße 55, Essen 45147, Germany.
| | - Maximilian S Schaefer
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, United States of America; Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, 375 Longwood Avenue, Boston, MA 02215, United States of America; Department of Anesthesiology, Duesseldorf University Hospital, Moorenstraße 5, Duesseldorf 40225, Germany.
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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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3
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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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4
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Deniel G, Dhelft F, Lancelot S, Orkisz M, Roux E, Mouton W, Benzerdjeb N, Richard JC, Bitker L. Pulmonary inflammation decreases with ultra-protective ventilation in experimental ARDS under VV-ECMO: a positron emission tomography study. Front Med (Lausanne) 2024; 11:1338602. [PMID: 38444415 PMCID: PMC10912585 DOI: 10.3389/fmed.2024.1338602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/24/2024] [Indexed: 03/07/2024] Open
Abstract
Background Experimentally, ultra-protective ventilation (UPV, tidal volumes [VT] < 4 mL.kg-1) strategies in conjunction with veno-venous extracorporeal membrane oxygenation (VV-ECMO) are associated with lesser ventilator-induced lung injuries (VILI) during acute respiratory distress syndrome (ARDS). However, whether these strategies reduce lung inflammation more effectively than protective ventilation (PV) remains unclear. We aimed to demonstrate that a UPV strategy decreases acute lung inflammation in comparison with PV in an experimental swine model of ARDS. Methods ARDS was induced by tracheal instillation of chlorhydric acid in sedated and paralyzed animals under mechanical ventilation. Animals were randomized to receive either UPV (VT 1 mL.kg-1, positive end-expiration pressure [PEEP] set to obtain plateau pressure between 20 and 25 cmH2O and respiratory rate [RR] at 5 min-1 under VV-ECMO) or PV (VT 6 mL.kg-1, PEEP set to obtain plateau pressure between 28 and 30 cmH2O and RR at 25 min-1) during 4 h. After 4 h, a positron emission tomography with [11C](R)-PK11195 (ligand to TSPO-bearing macrophages) injection was realized, coupled with quantitative computerized tomography (CT). Pharmacokinetic multicompartment models were used to quantify regional [11C](R)-PK11195 lung uptake. [11C](R)-PK11195 lung uptake and CT-derived respiratory variables were studied regionally across eight lung regions distributed along the antero-posterior axis. Results Five pigs were randomized to each study group. Arterial O2 partial pressure to inspired O2 fraction were not significantly different between study groups after experimental ARDS induction (75 [68-80] mmHg in a PV group vs. 87 [69-133] mmHg in a UPV group, p = 0.20). Compared to PV animals, UPV animals exhibited a significant decrease in the regional non-aerated compartment in the posterior lung levels, in mechanical power, and in regional dynamic strain and no statistical difference in tidal hyperinflation after 4 h. UPV animals had a significantly lower [11C](R)-PK11195 uptake, compared to PV animals (non-displaceable binding potential 0.35 [IQR, 0.20-0.59] in UPV animals and 1.01 [IQR, 0.75-1.59] in PV animals, p = 0.01). Regional [11C](R)-PK11195 uptake was independently associated with the interaction of regional tidal hyperinflation and regional lung compliance. Conclusion In an experimental model of ARDS, 4 h of UPV strategy significantly decreased lung inflammation, in relation to the control of VT-derived determinants of VILI.
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Affiliation(s)
- Guillaume Deniel
- Service de Médecine Intensive-Réanimation, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, Inserm, CREATIS UMR, Villeurbanne, France
| | - François Dhelft
- Service de Médecine Intensive-Réanimation, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
- Université de Lyon, Université LYON 1, Lyon, France
| | - Sophie Lancelot
- Université de Lyon, Université LYON 1, Lyon, France
- CERMEP – Imagerie du Vivant, Lyon, France
- Hospices Civils de Lyon, Lyon, France
| | - Maciej Orkisz
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, Inserm, CREATIS UMR, Villeurbanne, France
| | - Emmanuel Roux
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, Inserm, CREATIS UMR, Villeurbanne, France
| | - William Mouton
- Laboratoire Commun de Recherche Hospices Civils de Lyon/bioMérieux, Centre Hospitalier Lyon Sud, Hospices Civils de Lyon, Lyon, France
| | - Nazim Benzerdjeb
- Université de Lyon, Université LYON 1, Lyon, France
- Centre d’Anatomie et Cytologie Pathologique, Centre Hospitalier Lyon Sud, Hospices Civils de Lyon, Lyon, France
| | - Jean-Christophe Richard
- Service de Médecine Intensive-Réanimation, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, Inserm, CREATIS UMR, Villeurbanne, France
- Université de Lyon, Université LYON 1, Lyon, France
| | - Laurent Bitker
- Service de Médecine Intensive-Réanimation, Hôpital de la Croix-Rousse, Hospices Civils de Lyon, Lyon, France
- Univ Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, CNRS, Inserm, CREATIS UMR, Villeurbanne, France
- Université de Lyon, Université LYON 1, Lyon, France
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Tartler TM, Ahrens E, Munoz-Acuna R, Azizi BA, Chen G, Suleiman A, Wachtendorf LJ, Costa ELV, Talmor DS, Amato MBP, Baedorf-Kassis EN, Schaefer MS. High Mechanical Power and Driving Pressures are Associated With Postoperative Respiratory Failure Independent From Patients' Respiratory System Mechanics. Crit Care Med 2024; 52:68-79. [PMID: 37695139 DOI: 10.1097/ccm.0000000000006038] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
OBJECTIVES High mechanical power and driving pressure (ΔP) have been associated with postoperative respiratory failure (PRF) and may be important parameters guiding mechanical ventilation. However, it remains unclear whether high mechanical power and ΔP merely reflect patients with poor respiratory system mechanics at risk of PRF. We investigated the effect of mechanical power and ΔP on PRF in cohorts after exact matching by patients' baseline respiratory system compliance. DESIGN Hospital registry study. SETTING Academic hospital in New England. PATIENTS Adult patients undergoing general anesthesia between 2008 and 2020. INTERVENTION None. MEASUREMENTS AND MAIN RESULTS The primary exposure was high (≥ 6.7 J/min, cohort median) versus low mechanical power and the key-secondary exposure was high (≥ 15.0 cm H 2 O) versus low ΔP. The primary endpoint was PRF (reintubation or unplanned noninvasive ventilation within seven days). Among 97,555 included patients, 4,030 (4.1%) developed PRF. In adjusted analyses, high intraoperative mechanical power and ΔP were associated with higher odds of PRF (adjusted odds ratio [aOR] 1.37 [95% CI, 1.25-1.50]; p < 0.001 and aOR 1.45 [95% CI, 1.31-1.60]; p < 0.001, respectively). There was large variability in applied ventilatory parameters, dependent on the anesthesia provider. This facilitated matching of 63,612 (mechanical power cohort) and 53,260 (ΔP cohort) patients, yielding identical baseline standardized respiratory system compliance (standardized difference [SDiff] = 0.00) with distinctly different mechanical power (9.4 [2.4] vs 4.9 [1.3] J/min; SDiff = -2.33) and ΔP (19.3 [4.1] vs 11.9 [2.1] cm H 2 O; SDiff = -2.27). After matching, high mechanical power and ΔP remained associated with higher risk of PRF (aOR 1.30 [95% CI, 1.17-1.45]; p < 0.001 and aOR 1.28 [95% CI, 1.12-1.46]; p < 0.001, respectively). CONCLUSIONS High mechanical power and ΔP are associated with PRF independent of patient's baseline respiratory system compliance. Our findings support utilization of these parameters for titrating mechanical ventilation in the operating room and ICU.
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Affiliation(s)
- Tim M Tartler
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Elena Ahrens
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Ricardo Munoz-Acuna
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Basit A Azizi
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Guanqing Chen
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Aiman Suleiman
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesia, Intensive Care and Pain Management, Faculty of Medicine, University of Jordan, Amman, Jordan
| | - Luca J Wachtendorf
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Eduardo L V Costa
- Divisão de Pneumologia, Cardiopulmonary Department, Heart Institute (INCOR), São Paulo, SP, Brazil
| | - Daniel S Talmor
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Marcelo B P Amato
- Divisão de Pneumologia, Cardiopulmonary Department, Heart Institute (INCOR), São Paulo, SP, Brazil
| | - Elias N Baedorf-Kassis
- Department of Anesthesia, Critical Care and Pain Medicine, Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Division of Pulmonary and Critical Care, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Maximilian S Schaefer
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesia, Critical Care and Pain Medicine, Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Department of Anesthesiology, Düsseldorf University Hospital, Düsseldorf, Germany
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Mattson CL, Smith BJ. Modeling Ventilator-Induced Lung Injury and Neutrophil Infiltration to Infer Injury Interdependence. Ann Biomed Eng 2023; 51:2837-2852. [PMID: 37592044 PMCID: PMC10842244 DOI: 10.1007/s10439-023-03346-3] [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: 03/13/2023] [Accepted: 08/07/2023] [Indexed: 08/19/2023]
Abstract
Acute respiratory distress syndrome (ARDS) and ventilator-induced lung injury (VILI) are heterogeneous conditions. The spatiotemporal evolution of these heterogeneities is complex, and it is difficult to elucidate the mechanisms driving its progression. Through previous quantitative analyses, we explored the distributions of cellular injury and neutrophil infiltration in experimental VILI and discovered that VILI progression is characterized by both the formation of new injury in quasi-random locations and the expansion of existing injury clusters. Distributions of neutrophil infiltration do not correlate with cell injury progression and suggest a systemic response. To further examine the dynamics of VILI, we have developed a novel computational model that simulates damage (cellular injury progression and neutrophil infiltration) using a stochastic approach. Optimization of the model parameters to fit experimental data reveals that the range and strength of interdependence between existing and new damaged regions both increase as mechanical ventilation patterns become more injurious. The interdependence of cellular injury can be attributed to mechanical tethering forces, while the interdependence of neutrophils is likely due to longer-range cell signaling pathways.
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Affiliation(s)
- Courtney L Mattson
- Department of Bioengineering, University of Colorado Denver | Anschutz Medical Campus, 12705 E. Montview Blvd., Suite 100, Aurora, CO, 80045, USA
| | - Bradford J Smith
- Department of Bioengineering, University of Colorado Denver | Anschutz Medical Campus, 12705 E. Montview Blvd., Suite 100, Aurora, CO, 80045, USA.
- Pulmonary and Sleep Medicine, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, CO, USA.
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7
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Wang Y, Nardo L, Spencer BA, Abdelhafez YG, Li EJ, Omidvari N, Chaudhari AJ, Badawi RD, Jones T, Cherry SR, Wang G. Total-Body Multiparametric PET Quantification of 18F-FDG Delivery and Metabolism in the Study of Coronavirus Disease 2019 Recovery. J Nucl Med 2023; 64:1821-1830. [PMID: 37591539 PMCID: PMC10626370 DOI: 10.2967/jnumed.123.265723] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/05/2023] [Indexed: 08/19/2023] Open
Abstract
Conventional whole-body static 18F-FDG PET imaging provides a semiquantitative evaluation of overall glucose metabolism without insight into the specific transport and metabolic steps. Here we demonstrate the ability of total-body multiparametric 18F-FDG PET to quantitatively evaluate glucose metabolism using macroparametric quantification and assess specific glucose delivery and phosphorylation processes using microparametric quantification for studying recovery from coronavirus disease 2019 (COVID-19). Methods: The study included 13 healthy subjects and 12 recovering COVID-19 subjects within 8 wk of confirmed diagnosis. Each subject had a 1-h dynamic 18F-FDG scan on the uEXPLORER total-body PET/CT system. Semiquantitative SUV and the SUV ratio relative to blood (SUVR) were calculated for different organs to measure glucose utilization. Tracer kinetic modeling was performed to quantify the microparametric blood-to-tissue 18F-FDG delivery rate [Formula: see text] and the phosphorylation rate k 3, as well as the macroparametric 18F-FDG net influx rate ([Formula: see text]). Statistical tests were performed to examine differences between healthy subjects and recovering COVID-19 subjects. The effect of COVID-19 vaccination was also investigated. Results: We detected no significant difference in lung SUV but significantly higher lung SUVR and [Formula: see text] in COVID-19 recovery, indicating improved sensitivity of kinetic quantification for detecting the difference in glucose metabolism. A significant difference was also observed in the lungs with the phosphorylation rate k 3 but not with [Formula: see text], which suggests that glucose phosphorylation, rather than glucose delivery, drives the observed difference of glucose metabolism. Meanwhile, there was no or little difference in bone marrow 18F-FDG metabolism measured with SUV, SUVR, and [Formula: see text] but a significantly higher bone marrow [Formula: see text] in the COVID-19 group, suggesting a difference in glucose delivery. Vaccinated COVID-19 subjects had a lower lung [Formula: see text] and a higher spleen [Formula: see text] than unvaccinated COVID-19 subjects. Conclusion: Higher lung glucose metabolism and bone marrow glucose delivery were observed with total-body multiparametric 18F-FDG PET in recovering COVID-19 subjects than in healthy subjects, implying continued inflammation during recovery. Vaccination demonstrated potential protection effects. Total-body multiparametric PET of 18F-FDG can provide a more sensitive tool and more insights than conventional whole-body static 18F-FDG imaging to evaluate metabolic changes in systemic diseases such as COVID-19.
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Affiliation(s)
- Yiran Wang
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California;
- Department of Biomedical Engineering, University of California, Davis, Davis, California; and
| | - Lorenzo Nardo
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
| | - Benjamin A Spencer
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
- Department of Biomedical Engineering, University of California, Davis, Davis, California; and
| | - Yasser G Abdelhafez
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
- Nuclear Medicine Unit, South Egypt Cancer Institute, Assiut University, Assiut, Egypt
| | - Elizabeth J Li
- Department of Biomedical Engineering, University of California, Davis, Davis, California; and
| | - Negar Omidvari
- Department of Biomedical Engineering, University of California, Davis, Davis, California; and
| | - Abhijit J Chaudhari
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
| | - Ramsey D Badawi
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
- Department of Biomedical Engineering, University of California, Davis, Davis, California; and
| | - Terry Jones
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
| | - Simon R Cherry
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
- Department of Biomedical Engineering, University of California, Davis, Davis, California; and
| | - Guobao Wang
- Department of Radiology, Davis Medical Center, University of California, Sacramento, California
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8
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Zeng C, Zhu M, Motta-Ribeiro G, Lagier D, Hinoshita T, Zang M, Grogg K, Winkler T, Vidal Melo MF. Dynamic lung aeration and strain with positive end-expiratory pressure individualized to maximal compliance versus ARDSNet low-stretch strategy: a study in a surfactant depletion model of lung injury. Crit Care 2023; 27:307. [PMID: 37537654 PMCID: PMC10401825 DOI: 10.1186/s13054-023-04591-7] [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: 03/20/2023] [Accepted: 07/26/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND Positive end-expiratory pressure (PEEP) individualized to a maximal respiratory system compliance directly implies minimal driving pressures with potential outcome benefits, yet, raises concerns on static and dynamic overinflation, strain and cyclic recruitment. Detailed accurate assessment and understanding of these has been hampered by methodological limitations. We aimed to investigate the effects of a maximal compliance-guided PEEP strategy on dynamic lung aeration, strain and tidal recruitment using current four-dimensional computed tomography (CT) techniques and analytical methods of tissue deformation in a surfactant depletion experimental model of acute respiratory distress syndrome (ARDS). METHODS ARDS was induced by saline lung lavage in anesthetized and mechanically ventilated healthy sheep (n = 6). Animals were ventilated in a random sequence with: (1) ARDSNet low-stretch protocol; (2) maximal compliance PEEP strategy. Lung aeration, strain and tidal recruitment were acquired with whole-lung respiratory-gated high-resolution CT and quantified using registration-based techniques. RESULTS Relative to the ARDSNet low-stretch protocol, the maximal compliance PEEP strategy resulted in: (1) improved dynamic whole-lung aeration at end-expiration (0.456 ± 0.064 vs. 0.377 ± 0.101, P = 0.019) and end-inspiration (0.514 ± 0.079 vs. 0.446 ± 0.083, P = 0.012) with reduced non-aerated and increased normally-aerated lung mass without associated hyperinflation; (2) decreased aeration heterogeneity at end-expiration (coefficient of variation: 0.498 ± 0.078 vs. 0.711 ± 0.207, P = 0.025) and end-inspiration (0.419 ± 0.135 vs. 0.580 ± 0.108, P = 0.014) with higher aeration in dorsal regions; (3) tidal aeration with larger inspiratory increases in normally-aerated and decreases in poorly-aerated areas, and negligible in hyperinflated lung (Aeration × Strategy: P = 0.026); (4) reduced tidal strains in lung regions with normal-aeration (Aeration × Strategy: P = 0.047) and improved regional distributions with lower tidal strains in middle and ventral lung (Region-of-interest [ROI] × Strategy: P < 0.001); and (5) less tidal recruitment in middle and dorsal lung (ROI × Strategy: P = 0.044) directly related to whole-lung tidal strain (r = 0.751, P = 0.007). CONCLUSIONS In well-recruitable ARDS models, a maximal compliance PEEP strategy improved end-expiratory/inspiratory whole-lung aeration and its homogeneity without overinflation. It further reduced dynamic strain in middle-ventral regions and tidal recruitment in middle-dorsal areas. These findings suggest the maximal compliance strategy minimizing whole-lung dynamically quantified mechanisms of ventilator-induced lung injury with less cyclic recruitment and no additional overinflation in large heterogeneously expanded and recruitable lungs.
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Affiliation(s)
- Congli Zeng
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA.
| | - Min Zhu
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Gabriel 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, Brazil
| | - David Lagier
- Department of Cardiovascular Anesthesiology and Critical Care Medicine, University Hospital Timone, Marseille, France
| | | | - Mingyang Zang
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Kira Grogg
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Tilo Winkler
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Marcos F Vidal Melo
- Department of Anesthesiology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
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9
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Motta-Ribeiro GC, Winkler T, Costa ELV, de Prost N, Tucci MR, Vidal Melo MF. Worsening of lung perfusion to tissue density distributions during early acute lung injury. J Appl Physiol (1985) 2023; 135:239-250. [PMID: 37289955 PMCID: PMC10393328 DOI: 10.1152/japplphysiol.00028.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 05/12/2023] [Accepted: 06/05/2023] [Indexed: 06/10/2023] Open
Abstract
Lung perfusion magnitude and distribution are essential for oxygenation and, potentially, lung inflammation and protection during acute respiratory distress syndrome (ARDS). Yet, perfusion patterns and their relationship to inflammation are unknown pre-ARDS. We aimed to assess perfusion/density ratios and spatial perfusion-density distributions and associate these to lung inflammation, during early lung injury in large animals at different physiological conditions caused by different systemic inflammation and positive end-expiratory pressure (PEEP) levels. Sheep were protectively ventilated (16-24 h) and imaged for lung density, pulmonary capillary perfusion (13Nitrogen-saline), and inflammation (18F-fluorodeoxyglucose) using positron emission and computed tomography. We studied four conditions: permissive atelectasis (PEEP = 0 cmH2O); and ARDSNet low-stretch PEEP-setting strategy with supine moderate or mild endotoxemia, and prone mild endotoxemia. Perfusion/density heterogeneity increased pre-ARDS in all groups. Perfusion redistribution to density depended on ventilation strategy and endotoxemia level, producing more atelectasis in mild than moderate endotoxemia (P = 0.010) with the oxygenation-based PEEP-setting strategy. The spatial distribution of 18F-fluorodeoxyglucose uptake was related to local Q/D (P < 0.001 for Q/D group interaction). Moderate endotoxemia yielded markedly low/zero perfusion in normal-low density lung, with 13Nitrogen-saline perfusion indicating nondependent capillary obliteration. Prone animals' perfusion was remarkably homogeneously distributed with density. Lung perfusion redistributes heterogeneously to density during pre-ARDS protective ventilation in animals. This is associated with increased inflammation, nondependent capillary obliteration, and lung derecruitment susceptibility depending on endotoxemia level and ventilation strategy.NEW & NOTEWORTHY Perfusion redistribution does not follow lung density redistribution in the first 16-24 h of systemic endotoxemia and protective tidal volume mechanical ventilation. The same oxygenation-based positive end-expiratory pressure (PEEP)-setting strategy can lead at different endotoxemia levels to different perfusion redistributions, PEEP values, and lung aerations, worsening lung biomechanical conditions. During early acute lung injury, regional perfusion-to-tissue density ratio is associated with increased neutrophilic inflammation, and susceptibility to nondependent capillary occlusion and lung derecruitment, potentially marking and/or driving lung injury.
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Affiliation(s)
- Gabriel C Motta-Ribeiro
- Biomedical Engineering Program, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tilo Winkler
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States
| | - Eduardo L V Costa
- Divisão de Pneumologia, Faculdade de Medicina, Instituto do Coração (Incor), Hospital das Clínicas, Universidade de São Paulo, São Paulo, Brazil
- Instituto de Ensino e Pesquisa do Hospital Sírio Libanês, São Paulo, Brazil
| | - Nicolas de Prost
- Hôpitaux Universitaires Henri Mondor and Université Paris Est Créteil and INSERM - Unité U955, Créteil, France
| | - Mauro R Tucci
- Divisão de Pneumologia, Faculdade de Medicina, Instituto do Coração (Incor), Hospital das Clínicas, Universidade de São Paulo, São Paulo, Brazil
| | - Marcos F Vidal Melo
- Department of Anesthesiology, Columbia University Irving Medical Center, New York, New York, United States
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10
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Musch G. Molecular imaging of inflammation with PET in acute and ventilator-induced lung injury. Front Physiol 2023; 14:1177717. [PMID: 37457026 PMCID: PMC10338917 DOI: 10.3389/fphys.2023.1177717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/30/2023] [Indexed: 07/18/2023] Open
Abstract
This review focuses on methods to image acute lung inflammation with Positron Emission Tomography (PET). Four approaches are discussed that differ for biologic function of the PET reporter probe, radiotracer employed, and the specific aspect of the inflammatory response that is targeted. 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) is an enzyme substrate whose uptake is used to measure the metabolic activation of inflammatory cells during acute lung injury in the noncancerous lung. H2 15O and radiolabeled plasma proteins are inert molecules with the same physical characteristics as their nonradioactive counterparts and are used to measure edema and vascular permeability. Tagged enzyme or receptor inhibitors are used to probe expression of these targets induced by inflammatory stimuli. Lastly, cell-specific tracers are being developed to differentiate the cell types that contribute to the inflammatory response. Taken together, these methods cast PET imaging as a versatile and quantitative tool to measure inflammation in vivo noninvasively during acute and ventilator-induced lung injury.
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11
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Wang Y, Nardo L, Spencer BA, Abdelhafez YG, Li EJ, Omidvari N, Chaudhari AJ, Badawi RD, Jones T, Cherry SR, Wang G. Total-Body Multiparametric PET Quantification of 18 F-FDG Delivery and Metabolism in the Study of COVID-19 Recovery. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.03.26.23287673. [PMID: 37034643 PMCID: PMC10081414 DOI: 10.1101/2023.03.26.23287673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 04/23/2023]
Abstract
Conventional whole-body 18 F-FDG PET imaging provides a semi-quantitative evaluation of overall glucose metabolism without gaining insight into the specific transport and metabolic steps. Here we demonstrate the ability of total-body multiparametric 18 F-FDG PET to quantitatively evaluate glucose metabolism using macroparametric quantification and assess specific glucose delivery and phosphorylation processes using microparametric quantification for studying recovery from coronavirus disease 2019 (COVID-19). Methods The study included thirteen healthy subjects and twelve recovering COVID-19 subjects within eight weeks of confirmed diagnosis. Each subject had a dynamic 18 F-FDG scan on the uEXPLORER total-body PET/CT system for one hour. Semiquantitative standardized uptake value (SUV) and SUV ratio relative to blood (SUVR) were calculated for regions of interest (ROIs) in different organs to measure glucose utilization. Tracer kinetic modeling was performed to quantify microparametric rate constants K 1 and k 3 that characterize 18 F-FDG blood-to-tissue delivery and intracellular phosphorylation, respectively, and a macroparameter K i that represents 18 F-FDG net influx rate. Statistical tests were performed to examine differences between the healthy controls and recovering COVID-19 subjects. Impact of COVID-19 vaccination was investigated. We further generated parametric images to confirm the ROI-based analysis. Results We detected no significant difference in lung SUV but significantly higher lung SUVR and K i in the recovering COVID-19 subjects, indicating an improved sensitivity of kinetic quantification for detecting the difference in glucose metabolism. A significant difference was also observed in the lungs with the phosphorylation rate k 3 , but not with the delivery rate K 1 , which suggests it is glucose phosphorylation, not glucose delivery, that drives the observed difference of glucose metabolism in the lungs. Meanwhile, there was no or little difference in bone marrow metabolism measured with SUV, SUVR and K i , but a significant increase in bone-marrow 18 F-FDG delivery rate K 1 in the COVID-19 group ( p < 0.05), revealing a difference of glucose delivery in this immune-related organ. The observed differences were lower or similar in vaccinated COVID-19 subjects as compared to unvaccinated ones. The organ ROI-based findings were further supported by parametric images. Conclusions Higher lung glucose metabolism and bone-marrow glucose delivery were observed with total-body multiparametric 18 F-FDG PET in recovering COVID-19 subjects as compared to healthy subjects, which suggests continued inflammation due to COVID-19 during the early stages of recovery. Total-body multiparametric PET of 18 F-FDG delivery and metabolism can provide a more sensitive tool and more insights than conventional static whole-body 18 F-FDG imaging to evaluate metabolic changes in systemic diseases such as COVID-19.
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Affiliation(s)
- Yiran Wang
- Department of Radiology, University of California Davis Medical Center
- Department of Biomedical Engineering, University of California, Davis
| | - Lorenzo Nardo
- Department of Radiology, University of California Davis Medical Center
| | - Benjamin A. Spencer
- Department of Radiology, University of California Davis Medical Center
- Department of Biomedical Engineering, University of California, Davis
| | - Yasser G. Abdelhafez
- Department of Radiology, University of California Davis Medical Center
- Nuclear Medicine Unit, South Egypt Cancer Institute, Assiut University, Egypt
| | - Elizabeth J. Li
- Department of Biomedical Engineering, University of California, Davis
| | - Negar Omidvari
- Department of Biomedical Engineering, University of California, Davis
| | | | - Ramsey D. Badawi
- Department of Radiology, University of California Davis Medical Center
- Department of Biomedical Engineering, University of California, Davis
| | - Terry Jones
- Department of Radiology, University of California Davis Medical Center
| | - Simon R. Cherry
- Department of Radiology, University of California Davis Medical Center
- Department of Biomedical Engineering, University of California, Davis
| | - Guobao Wang
- Department of Radiology, University of California Davis Medical Center
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12
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Tartler TM, Wachtendorf LJ, Suleiman A, Blank M, Ahrens E, Linhardt FC, Althoff FC, Chen G, Santer P, Nagrebetsky A, Eikermann M, Schaefer MS. The association of intraoperative low driving pressure ventilation and nonhome discharge: a historical cohort study. Can J Anaesth 2023; 70:359-373. [PMID: 36697936 DOI: 10.1007/s12630-022-02378-y] [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: 04/12/2022] [Revised: 08/07/2022] [Accepted: 09/21/2022] [Indexed: 01/26/2023] Open
Abstract
PURPOSE To evaluate whether intraoperative ventilation using lower driving pressure decreases the risk of nonhome discharge. METHODS We conducted a historical cohort study of patients aged ≥ 60 yr who were living at home before undergoing elective, noncardiothoracic surgery at two tertiary healthcare networks in Massachusetts between 2007 and 2018. We assessed the association of the median driving pressure during intraoperative mechanical ventilation with nonhome discharge using multivariable logistic regression analysis, adjusted for patient and procedural factors. Contingent on the primary association, we assessed effect modification by patients' baseline risk and mediation by postoperative respiratory failure. RESULTS Of 87,407 included patients, 12,584 (14.4%) experienced nonhome discharge. In adjusted analyses, a lower driving pressure was associated with a lower risk of nonhome discharge (adjusted odds ratio [aOR], 0.88; 95% confidence interval [CI], 0.83 to 0.93, per 10 cm H2O decrease; P < 0.001). This association was magnified in patients with a high baseline risk (aOR, 0.77; 95% CI, 0.73 to 0.81, per 10 cm H2O decrease, P-for-interaction < 0.001). The findings were confirmed in 19,518 patients matched for their baseline respiratory system compliance (aOR, 0.90; 95% CI, 0.81 to 1.00; P = 0.04 for low [< 15 cm H2O] vs high [≥ 15 cm H2O] driving pressures). A lower risk of respiratory failure mediated the association of a low driving pressure with nonhome discharge (20.8%; 95% CI, 15.0 to 56.8; P < 0.001). CONCLUSIONS Intraoperative ventilation maintaining lower driving pressure was associated with a lower risk of nonhome discharge, which can be partially explained by lowered rates of postoperative respiratory failure. Future randomized controlled trials should target driving pressure as a potential intervention to decrease nonhome discharge.
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Affiliation(s)
- Tim M Tartler
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Luca J Wachtendorf
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Aiman Suleiman
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Department of Anesthesia and Intensive Care, Faculty of Medicine, The University of Jordan, Amman, Jordan
| | - Michael Blank
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Elena Ahrens
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Felix C Linhardt
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Friederike C Althoff
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Guanqing Chen
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Peter Santer
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Alexander Nagrebetsky
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Matthias Eikermann
- Department of Anesthesiology, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY, USA
- Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen, Essen, Germany
| | - Maximilian S Schaefer
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA, 02215, USA.
- Center for Anesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
- Klinik für Anästhesiologie, Universitätsklinikum Düsseldorf, Düsseldorf, Germany.
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13
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Girard M, Roy Cardinal MH, Chassé M, Garneau S, Cavayas YA, Cloutier G, Denault AY. Regional pleural strain measurements during mechanical ventilation using ultrasound elastography: A randomized, crossover, proof of concept physiologic study. Front Med (Lausanne) 2022; 9:935482. [PMID: 36186794 PMCID: PMC9520064 DOI: 10.3389/fmed.2022.935482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Background Mechanical ventilation is a common therapy in operating rooms and intensive care units. When ill-adapted, it can lead to ventilator-induced lung injury (VILI), which is associated with poor outcomes. Excessive regional pulmonary strain is thought to be a major mechanism responsible for VILI. Scarce bedside methods exist to measure regional pulmonary strain. We propose a novel way to measure regional pleural strain using ultrasound elastography. The objective of this study was to assess the feasibility and reliability of pleural strain measurement by ultrasound elastography and to determine if elastography parameters would correlate with varying tidal volumes. Methods A single-blind randomized crossover proof of concept study was conducted July to October 2017 at a tertiary care referral center. Ten patients requiring general anesthesia for elective surgery were recruited. After induction, patients received tidal volumes of 6, 8, 10, and 12 mL.kg–1 in random order, while pleural ultrasound cineloops were acquired at 4 standardized locations. Ultrasound radiofrequency speckle tracking allowed computing various pleural translation, strain and shear components. We screened 6 elastography parameters (lateral translation, lateral absolute translation, lateral strain, lateral absolute strain, lateral absolute shear and Von Mises Strain) to identify those with the best dose-response with tidal volumes using linear mixed effect models. Goodness-of-fit was assessed by the coefficient of determination. Intraobserver, interobserver and test-retest reliability were calculated using intraclass correlation coefficients. Results Analysis was possible in 90.7% of ultrasound cineloops. Lateral absolute shear, lateral absolute strain and Von Mises strain varied significantly with tidal volume and offered the best dose-responses and data modeling fits. Point estimates for intraobserver reliability measures were excellent for all 3 parameters (0.94, 0.94, and 0.93, respectively). Point estimates for interobserver (0.84, 0.83, and 0.77, respectively) and test-retest (0.85, 0.82, and 0.76, respectively) reliability measures were good. Conclusion Strain imaging is feasible and reproducible. Future studies will have to investigate the clinical relevance of this novel imaging modality. Clinical trial registration www.Clinicaltrials.gov, identifier NCT03092557.
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Affiliation(s)
- Martin Girard
- Department of Anesthesiology, University of Montreal Hospital, Montréal, QC, Canada
- Division of Critical Care, Department of Medicine, University of Montreal Hospital, Montréal, QC, Canada
- University of Montreal Hospital Research Center, Montréal, QC, Canada
- *Correspondence: Martin Girard,
| | - Marie-Hélène Roy Cardinal
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center, Montréal, QC, Canada
| | - Michaël Chassé
- Division of Critical Care, Department of Medicine, University of Montreal Hospital, Montréal, QC, Canada
- Department of Medicine, University of Montreal, Montréal, QC, Canada
| | - Sébastien Garneau
- Department of Anesthesiology, University of Montreal Hospital, Montréal, QC, Canada
| | | | - Guy Cloutier
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center, Montréal, QC, Canada
- Department of Radiology, Radio-Oncology and Nuclear Medicine, Institute of Biomedical Engineering, University of Montreal, Montréal, QC, Canada
| | - André Y. Denault
- Department of Anesthesiology, Montreal Heart Institute, Montréal, QC, Canada
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14
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Mattson CL, Okamura K, Hume PS, Smith BJ. Spatiotemporal distribution of cellular injury and leukocytes during the progression of ventilator-induced lung injury. Am J Physiol Lung Cell Mol Physiol 2022; 323:L281-L296. [PMID: 35700201 PMCID: PMC9423727 DOI: 10.1152/ajplung.00207.2021] [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: 05/12/2021] [Revised: 05/26/2022] [Accepted: 06/12/2022] [Indexed: 11/22/2022] Open
Abstract
Supportive mechanical ventilation is a necessary lifesaving treatment for acute respiratory distress syndrome (ARDS). This intervention often leads to injury exacerbation by ventilator-induced lung injury (VILI). Patterns of injury in ARDS and VILI are recognized to be heterogeneous; however, quantification of these injury distributions remains incomplete. Developing a more detailed understanding of injury heterogeneity, particularly how it varies in space and time, can help elucidate the mechanisms of VILI pathogenesis. Ultimately, this knowledge can be used to develop protective ventilation strategies that slow disease progression. To expand existing knowledge of VILI heterogeneity, we document the spatial evolution of cellular injury distribution and leukocyte infiltration, on the micro- and macroscales, during protective and injurious mechanical ventilation. We ventilated naïve mice using either high inspiratory pressure and zero positive end-expiratory pressure ventilation or low tidal volume with positive end-expiratory pressure. Distributions of cellular injury, identified with propidium iodide staining, were microscopically analyzed at three levels of injury severity. Cellular injury initiated in diffuse, quasi-random patterns, and progressed through expansion of high-density regions of injured cells termed "injury clusters." The density profile of the expanding injury regions suggests that stress shielding occurs, protecting the already injured regions from further damage. Spatial distribution of leukocytes did not correlate with that of cellular injury or ventilation-induced changes in lung function. These results suggest that protective ventilation protocols should protect the interface between healthy and injured regions to stymie injury propagation.
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Affiliation(s)
- Courtney L Mattson
- Department of Bioengineering, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Kayo Okamura
- Department of Bioengineering, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
| | - Patrick S Hume
- Department of Pulmonary, Critical Care, and Sleep Medicine, National Jewish Health, Denver, Colorado
- Department of Pediatrics, Pulmonary and Sleep Medicine, School of Medicine, University of Colorado, Aurora, Colorado
| | - Bradford J Smith
- Department of Bioengineering, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado
- Department of Pediatrics, Pulmonary and Sleep Medicine, School of Medicine, University of Colorado, Aurora, Colorado
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15
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Suleiman A, Costa E, Santer P, Tartler TM, Wachtendorf LJ, Teja B, Chen G, Baedorf-Kassis E, Nagrebetsky A, Vidal Melo MF, Eikermann M, Schaefer MS. Association between intraoperative tidal volume and postoperative respiratory complications is dependent on respiratory elastance: a retrospective, multicentre cohort study. Br J Anaesth 2022; 129:263-272. [PMID: 35690489 PMCID: PMC9837741 DOI: 10.1016/j.bja.2022.05.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 02/18/2022] [Accepted: 05/05/2022] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The impact of high vs low intraoperative tidal volumes on postoperative respiratory complications remains unclear. We hypothesised that the effect of intraoperative tidal volume on postoperative respiratory complications is dependent on respiratory system elastance. METHODS We retrospectively recorded tidal volume (Vt; ml kg-1 ideal body weight [IBW]) in patients undergoing elective, non-cardiothoracic surgery from hospital registry data. The primary outcome was respiratory failure (requiring reintubation within 7 days of surgery, desaturation after extubation, or both). The primary exposure was defined as the interaction between Vt and standardised respiratory system elastance (driving pressure divided by Vt; cm H2O/[ml kg-1]). Multivariable logistic regression models, with and without interaction terms (which categorised Vt as low [Vt ≤8 ml kg-1] or high [Vt >8 ml kg-1]), were adjusted for potential confounders. Additional analyses included path mediation analysis and fractional polynomial modelling. RESULTS Overall, 10 821/197 474 (5.5%) patients sustained postoperative respiratory complications. Higher Vt was associated with greater risk of postoperative respiratory complications (adjusted odds ratio=1.42 per ml kg-1; 95% confidence interval [CI], 1.35-1.50]; P<0.001). This association was modified by respiratory system elastance (P<0.001); in patients with low compliance (<42.4 ml cm H2O-1), higher Vt was associated with greater risk of postoperative respiratory complications (adjusted risk difference=0.3% [95% CI, 0.0-0.5] at 41.2 ml cm H2O-1 compliance, compared with 5.8% [95% CI, 3.8-7.8] at 14 ml cm H2O-1 compliance). This association was absent when compliance exceeded 41.2 ml cm H2O-1. Adverse effects associated with high Vt were entirely mediated by driving pressures (P<0.001). CONCLUSIONS The association of harm with higher tidal volumes during intraoperative mechanical ventilation is modified by respiratory system elastance. These data suggest that respiratory elastance should inform the design of perioperative trials testing intraoperative ventilatory strategies.
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Affiliation(s)
- Aiman Suleiman
- Department of Anaesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Centre, Boston, MA, USA,Center for Anaesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Centre, Boston, MA, USA,Department of Anaesthesia and Intensive Care, Faculty of Medicine, University of Jordan, Amman, Jordan
| | - Eduardo Costa
- Laboratório de Pneumologia LIM-09, Disciplina de Pneumologia, Heart Institute (Incor), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Sao Paulo, Brazil,Research and Education Institute, Hospital Sírio-Libanes, Sao Paulo, Brazil
| | - Peter Santer
- Department of Anaesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Centre, Boston, MA, USA
| | - Tim M. Tartler
- Department of Anaesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Centre, Boston, MA, USA,Center for Anaesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Centre, Boston, MA, USA
| | - Luca J. Wachtendorf
- Department of Anaesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Centre, Boston, MA, USA,Center for Anaesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Centre, Boston, MA, USA,Department of Anaesthesiology, Montefiore Medical Centre and Albert Einstein College of Medicine, Bronx, NY, USA
| | - Bijan Teja
- Department of Anaesthesiology and Pain Medicine and Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| | - Guanqing Chen
- Center for Anaesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Centre, Boston, MA, USA
| | - Elias Baedorf-Kassis
- Department of Pulmonary, Critical Care & Sleep Medicine, Beth Israel Deaconess Medical Centre, Boston, MA, USA
| | - Alexander Nagrebetsky
- Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Marcos F. Vidal Melo
- Department of Anesthesiology, Columbia University Irving Medical Center, New York, NY, USA,Corresponding authors.
| | - Matthias Eikermann
- Department of Anaesthesiology, Montefiore Medical Centre and Albert Einstein College of Medicine, Bronx, NY, USA,Klinik für Anästhesiologie und Intensivmedizin, Universität Duisburg-Essen, Essen, Germany
| | - Maximilian S. Schaefer
- Department of Anaesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Centre, Boston, MA, USA,Center for Anaesthesia Research Excellence (CARE), Beth Israel Deaconess Medical Centre, Boston, MA, USA,Department of Anaesthesiology, Düsseldorf University Hospital, Dusseldorf, Germany,Corresponding authors.
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16
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Araos J, Cruces P, Martin-Flores M, Donati P, Gleed RD, Boullhesen-Williams T, Perez A, Staffieri F, Retamal J, Vidal Melo MF, Hurtado DE. Distribution and Magnitude of Regional Volumetric Lung Strain and Its Modification by PEEP in Healthy Anesthetized and Mechanically Ventilated Dogs. Front Vet Sci 2022; 9:839406. [PMID: 35359684 PMCID: PMC8964072 DOI: 10.3389/fvets.2022.839406] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 01/27/2022] [Indexed: 11/24/2022] Open
Abstract
The present study describes the magnitude and spatial distribution of lung strain in healthy anesthetized, mechanically ventilated dogs with and without positive end-expiratory pressure (PEEP). Total lung strain (LSTOTAL) has a dynamic (LSDYNAMIC) and a static (LSSTATIC) component. Due to lung heterogeneity, global lung strain may not accurately represent regional total tissue lung strain (TSTOTAL), which may also be described by a regional dynamic (TSDYNAMIC) and static (TSSTATIC) component. Six healthy anesthetized beagles (12.4 ± 1.4 kg body weight) were placed in dorsal recumbency and ventilated with a tidal volume of 15 ml/kg, respiratory rate of 15 bpm, and zero end-expiratory pressure (ZEEP). Respiratory system mechanics and full thoracic end-expiratory and end-inspiratory CT scan images were obtained at ZEEP. Thereafter, a PEEP of 5 cmH2O was set and respiratory system mechanics measurements and end-expiratory and end-inspiratory images were repeated. Computed lung volumes from CT scans were used to evaluate the global LSTOTAL, LSDYNAMIC, and LSSTATIC during PEEP. During ZEEP, LSSTATIC was assumed zero; therefore, LSTOTAL was the same as LSDYNAMIC. Image segmentation was applied to CT images to obtain maps of regional TSTOTAL, TSDYNAMIC, and TSSTATIC during PEEP, and TSDYNAMIC during ZEEP. Compliance increased (p = 0.013) and driving pressure decreased (p = 0.043) during PEEP. PEEP increased the end-expiratory lung volume (p < 0.001) and significantly reduced global LSDYNAMIC (33.4 ± 6.4% during ZEEP, 24.0 ± 4.6% during PEEP, p = 0.032). LSSTATIC by PEEP was larger than the reduction in LSDYNAMIC; therefore, LSTOTAL at PEEP was larger than LSDYNAMIC at ZEEP (p = 0.005). There was marked topographic heterogeneity of regional strains. PEEP induced a significant reduction in TSDYNAMIC in all lung regions (p < 0.05). Similar to global findings, PEEP-induced TSSTATIC was larger than the reduction in TSDYNAMIC; therefore, PEEP-induced TSTOTAL was larger than TSDYNAMIC at ZEEP. In conclusion, PEEP reduced both global and regional estimates of dynamic strain, but induced a large static strain. Given that lung injury has been mostly associated with tidal deformation, limiting dynamic strain may be an important clinical target in healthy and diseased lungs, but this requires further study.
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Affiliation(s)
- Joaquin Araos
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
- *Correspondence: Joaquin Araos
| | - Pablo Cruces
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipu, Santiago, Chile
| | - Manuel Martin-Flores
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Pablo Donati
- Department of Anesthesiology and Pain Management, Faculty of Veterinary Sciences, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Robin D. Gleed
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Tomas Boullhesen-Williams
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Agustin Perez
- Department of Structural and Geotechnical Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Francesco Staffieri
- Department of Emergency and Organ Transplantation, Section of Veterinary Clinics and Animal Production, University of Bari, Bari, Italy
| | - Jaime Retamal
- Department of Intensive Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcos F. Vidal Melo
- Division of Cardiothoracic Anesthesiology, Department of Anesthesiology, Columbia University Irving Medical Center, New York, NY, United States
| | - Daniel E. Hurtado
- Department of Structural and Geotechnical Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
- Daniel E. Hurtado
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17
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Nakahashi S, Imai H, Shimojo N, Magata Y, Einama T, Hayakawa M, Wada T, Morimoto Y, Gando S. Effects of the Prone Position on Regional Neutrophilic Lung Inflammation According to 18F-FDG Pet in an Experimental Ventilator-Induced Lung Injury Model. Shock 2022; 57:298-308. [PMID: 34107528 DOI: 10.1097/shk.0000000000001818] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
ABSTRACT Ventilator-induced lung injury (VILI) can be life-threatening and it is important to prevent the development of VILI. It remains unclear whether the prone position affects neutrophilic inflammation in the lung regions in vivo, which plays a crucial role in the pathogenesis of VILI. This study aimed to assess the relationship between the use of the prone position and the development of VILI-associated regional neutrophilic lung inflammation. Regional neutrophilic lung inflammation and lung aeration during low tidal volume mechanical ventilation were assessed using in vivo 2-deoxy-2-[(18)F] fluoro-D-glucose (18F-FDG) positron emission tomography and computed tomography in acutely experimentally injured rabbit lungs (lung injury induced by lung lavage and excessive ventilation). Direct comparisons were made among three groups: control, supine, and prone positions. After approximately 7 h, tissue-normalized 18F-FDG uptake differed significantly between the supine and prone positions (SUP: 0.038 ± 0.014 vs. PP: 0.029 ± 0.008, P = 0.038), especially in the ventral region (SUP: 0.052 ± 0.013 vs. PP: 0.026 ± 0.007, P = 0.003). The use of the prone position reduced lung inhomogeneities, which was demonstrated by the correction of the disproportionate rate of voxel gas over the given lung region. The progression of neutrophilic inflammation was affected by the interaction between the total strain (for aeration) and the inhomogeneity. The prone position is effective in slowing down the progression of VILI-associated neutrophilic inflammation. Under low-tidal-volume ventilation, the main drivers of its effect may be homogenization of lung tissue and that of mechanical forces.
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Affiliation(s)
- Susumu Nakahashi
- Department of Emergency and Critical Care Center, Mie University Hospital, Tsu, Japan
| | - Hiroshi Imai
- Department of Emergency and Critical Care Center, Mie University Hospital, Tsu, Japan
| | - Nobutake Shimojo
- Department of Emergency and Critical Care Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Yasuhiro Magata
- Department of Molecular Imaging, Institute for Medical Photonics Research, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Takahiro Einama
- Department of Surgery, National Defense Medical College, Tokorozawa, Japan
| | - Mineji Hayakawa
- Division of Acute and Critical Care Medicine, Department of Anesthesiology and Critical Care Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Takeshi Wada
- Division of Acute and Critical Care Medicine, Department of Anesthesiology and Critical Care Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Yuji Morimoto
- Division of Anesthesia and Perioperative Medicine, Department of Anesthesiology and Critical Care Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Satoshi Gando
- Division of Acute and Critical Care Medicine, Department of Anesthesiology and Critical Care Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan
- Department of Acute and Critical Care Medicine, Sapporo Higashi Tokushukai Hospital, Sapporo, Japan
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18
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Liu W, Tao G, Zhang Y, Xiao W, Zhang J, Liu Y, Lu Z, Hua T, Yang M. A Simple Weaning Model Based on Interpretable Machine Learning Algorithm for Patients With Sepsis: A Research of MIMIC-IV and eICU Databases. Front Med (Lausanne) 2022; 8:814566. [PMID: 35118099 PMCID: PMC8804204 DOI: 10.3389/fmed.2021.814566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 12/13/2021] [Indexed: 11/13/2022] Open
Abstract
BackgroundInvasive mechanical ventilation plays an important role in the prognosis of patients with sepsis. However, there are, currently, no tools specifically designed to assess weaning from invasive mechanical ventilation in patients with sepsis. The aim of our study was to develop a practical model to predict weaning in patients with sepsis.MethodsWe extracted patient information from the Medical Information Mart for Intensive Care Database-IV (MIMIC-IV) and the eICU Collaborative Research Database (eICU-CRD). Kaplan–Meier curves were plotted to compare the 28-day mortality between patients who successfully weaned and those who failed to wean. Subsequently, MIMIC-IV was divided into a training set and an internal verification set, and the eICU-CRD was designated as the external verification set. We selected the best model to simplify the internal and external validation sets based on the performance of the model.ResultsA total of 5020 and 7081 sepsis patients with invasive mechanical ventilation in MIMIC-IV and eICU-CRD were included, respectively. After matching, weaning was independently associated with 28-day mortality and length of ICU stay (p < 0.001 and p = 0.002, respectively). After comparison, 35 clinical variables were extracted to build weaning models. XGBoost performed the best discrimination among the models in the internal and external validation sets (AUROC: 0.80 and 0.86, respectively). Finally, a simplified model was developed based on XGBoost, which included only four variables. The simplified model also had good predictive performance (AUROC:0.75 and 0.78 in internal and external validation sets, respectively) and was developed into a web-based tool for further review.ConclusionsWeaning success is independently related to short-term mortality in patients with sepsis. The simplified model based on the XGBoost algorithm provides good predictive performance and great clinical applicablity for weaning, and a web-based tool was developed for better clinical application.
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Affiliation(s)
- Wanjun Liu
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- The Laboratory of Cardiopulmonary Resuscitation and Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Gan Tao
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yijun Zhang
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- The Laboratory of Cardiopulmonary Resuscitation and Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Wenyan Xiao
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- The Laboratory of Cardiopulmonary Resuscitation and Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jin Zhang
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- The Laboratory of Cardiopulmonary Resuscitation and Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yu Liu
- Key Laboratory of Intelligent Computing and Signal Processing, Ministry of Education, Anhui University, Hefei, China
| | - Zongqing Lu
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- The Laboratory of Cardiopulmonary Resuscitation and Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Tianfeng Hua
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- The Laboratory of Cardiopulmonary Resuscitation and Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Min Yang
- The 2nd Department of Intensive Care Unit, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- The Laboratory of Cardiopulmonary Resuscitation and Critical Care Medicine, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
- *Correspondence: Min Yang
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19
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Lagier D, Zeng C, Fernandez-Bustamante A, Melo MFV. Perioperative Pulmonary Atelectasis: Part II. Clinical Implications. Anesthesiology 2022; 136:206-236. [PMID: 34710217 PMCID: PMC9885487 DOI: 10.1097/aln.0000000000004009] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The development of pulmonary atelectasis is common in the surgical patient. Pulmonary atelectasis can cause various degrees of gas exchange and respiratory mechanics impairment during and after surgery. In its most serious presentations, lung collapse could contribute to postoperative respiratory insufficiency, pneumonia, and worse overall clinical outcomes. A specific risk assessment is critical to allow clinicians to optimally choose the anesthetic technique, prepare appropriate monitoring, adapt the perioperative plan, and ensure the patient's safety. Bedside diagnosis and management have benefited from recent imaging advancements such as lung ultrasound and electrical impedance tomography, and monitoring such as esophageal manometry. Therapeutic management includes a broad range of interventions aimed at promoting lung recruitment. During general anesthesia, these strategies have consistently demonstrated their effectiveness in improving intraoperative oxygenation and respiratory compliance. Yet these same intraoperative strategies may fail to affect additional postoperative pulmonary outcomes. Specific attention to the postoperative period may be key for such outcome impact of lung expansion. Interventions such as noninvasive positive pressure ventilatory support may be beneficial in specific patients at high risk for pulmonary atelectasis (e.g., obese) or those with clinical presentations consistent with lung collapse (e.g., postoperative hypoxemia after abdominal and cardiothoracic surgeries). Preoperative interventions may open new opportunities to minimize perioperative lung collapse and prevent pulmonary complications. Knowledge of pathophysiologic mechanisms of atelectasis and their consequences in the healthy and diseased lung should provide the basis for current practice and help to stratify and match the intensity of selected interventions to clinical conditions.
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Affiliation(s)
- David Lagier
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Congli Zeng
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Marcos F. Vidal Melo
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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20
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Musch G. New Frontiers in Functional and Molecular Imaging of the Acutely Injured Lung: Pathophysiological Insights and Research Applications. Front Physiol 2021; 12:762688. [PMID: 34955883 PMCID: PMC8696200 DOI: 10.3389/fphys.2021.762688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 11/17/2021] [Indexed: 11/13/2022] Open
Abstract
This review focuses on the advances in the understanding of the pathophysiology of ventilator-induced and acute lung injury that have been afforded by technological development of imaging methods over the last decades. Examples of such advances include the establishment of regional lung mechanical strain as a determinant of ventilator-induced lung injury, the relationship between alveolar recruitment and overdistension, the regional vs. diffuse nature of pulmonary involvement in acute respiratory distress syndrome (ARDS), the identification of the physiological determinants of the response to recruitment interventions, and the pathophysiological significance of metabolic alterations in the acutely injured lung. Taken together, these advances portray multimodality imaging as the next frontier to both advance knowledge of the pathophysiology of these conditions and to tailor treatment to the individual patient's condition.
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Affiliation(s)
- Guido Musch
- Department of Anesthesiology and Perioperative Medicine, University of Massachusetts Medical School, Worcester, MA, United States
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21
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Araos J, Lacitignola L, de Monte V, Stabile M, Porter I, Hurtado DE, Perez A, Crovace A, Grasso S, Martin-Flores M, Staffieri F. Evaluation of Lung Aeration and Respiratory System Mechanics in Obese Dogs Ventilated With Tidal Volumes Based on Ideal vs. Current Body Weight. Front Vet Sci 2021; 8:704863. [PMID: 34660755 PMCID: PMC8517180 DOI: 10.3389/fvets.2021.704863] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 09/06/2021] [Indexed: 11/23/2022] Open
Abstract
We describe the respiratory mechanics and lung aeration in anesthetized obese dogs ventilated with tidal volumes (VT) based on ideal (VTi) vs. current (VTc) body weight. Six dogs with body condition scores ≥ 8/9 were included. End-expiratory respiratory mechanics and end-expiratory CT-scan were obtained at baseline for each dog. Thereafter, dogs were ventilated with VT 15 ml kg−1 based on VTi and VTc, applied randomly. Respiratory mechanics and CT-scan were repeated at end-inspiration during VTi and VTc. Data analyzed with linear mixed models and reported as mean ± SD or median [range]. Statistical significance p < 0.05. The elastance of the lung, chest wall and respiratory system indexed by ideal body weight (IBW) were positively correlated with body fat percentage, whereas the functional residual capacity indexed by IBW was negatively correlated with body fat percentage. At end-expiration, aeration (%) was: hyperaeration 0.03 [0.00–3.35], normoaeration 69.7 [44.6–82.2], hypoaeration 29.3 [13.6–49.4] and nonaeration (1.06% [0.37–6.02]). Next to the diaphragm, normoaeration dropped to 12 ± 11% and hypoaeration increased to 90 ± 8%. No differences in aeration between groups were found at end-inspiration. Airway driving pressure (cm H2O) was higher (p = 0.002) during VTc (9.8 ± 0.7) compared with VTi (7.6 ± 0.4). Lung strain was higher (p = 0.014) during VTc (55 ± 21%) than VTi (38 ± 10%). The stress index was higher (p = 0.012) during VTc (SI = 1.07 [0.14]) compared with VTi (SI = 0.93 [0.18]). This study indicates that body fat percentage influences the magnitude of lung, chest wall, and total respiratory system elastance and resistance, as well as functional residual capacity. Further, these results indicate that obese dogs have extensive areas of hypoaerated lungs, especially in caudodorsal regions. Finally, lung strain and airway driving pressure, surrogates of lung deformation, are higher during VTc than during VTi, suggesting that in obese anesthetized dogs, ventilation protocols based on IBW may be advantageous.
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Affiliation(s)
- Joaquin Araos
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Luca Lacitignola
- Section of Veterinary Clinics and Animal Production, Department of Emergency and Organ Transplantation D.E.O.T., "Aldo Moro" University of Bari, Bari, Italy
| | - Valentina de Monte
- Section of Veterinary Clinics and Animal Production, Department of Emergency and Organ Transplantation D.E.O.T., "Aldo Moro" University of Bari, Bari, Italy
| | - Marzia Stabile
- Section of Veterinary Clinics and Animal Production, Department of Emergency and Organ Transplantation D.E.O.T., "Aldo Moro" University of Bari, Bari, Italy
| | - Ian Porter
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Daniel E Hurtado
- Department of Structural and Geotechnical Engineering, School of Engineering, Pontificia Universidad Catolica de Chile, Santiago, Chile.,Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Catolica de Chile, Santiago, Chile.,Millennium Nucleus for Cardiovascular Magnetic Resonance, Santiago, Chile
| | - Agustín Perez
- Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Catolica de Chile, Santiago, Chile
| | - Antonio Crovace
- Section of Veterinary Clinics and Animal Production, Department of Emergency and Organ Transplantation D.E.O.T., "Aldo Moro" University of Bari, Bari, Italy
| | - Salvatore Grasso
- Section of Anesthesia and Intensive Care, Department of Emergency and Organ Transplantation D.E.O.T., "Aldo Moro" University of Bari, Bari, Italy
| | - Manuel Martin-Flores
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
| | - Francesco Staffieri
- Section of Veterinary Clinics and Animal Production, Department of Emergency and Organ Transplantation D.E.O.T., "Aldo Moro" University of Bari, Bari, Italy
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22
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Cornejo R, Iturrieta P, Olegário TMM, Kajiyama C, Arellano D, Guiñez D, Cerda MA, Brito R, Gajardo AIJ, Lazo M, López L, Morais CCA, González S, Zavala M, Rojas V, Medel JN, Hurtado DE, Bruhn A, Ramos C, Estuardo N. Estimation of changes in cyclic lung strain by electrical impedance tomography: Proof-of-concept study. Acta Anaesthesiol Scand 2021; 65:228-235. [PMID: 33037607 DOI: 10.1111/aas.13723] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 09/15/2020] [Accepted: 10/01/2020] [Indexed: 02/06/2023]
Abstract
RATIONALE Cyclic strain may be a determinant of ventilator-induced lung injury. The standard for strain assessment is the computed tomography (CT), which does not allow continuous monitoring and exposes to radiation. Electrical impedance tomography (EIT) is able to monitor changes in regional lung ventilation. In addition, there is a correlation between mechanical deformation of materials and detectable changes in its electrical impedance, making EIT a potential surrogate for cyclic lung strain measured by CT (StrainCT ). OBJECTIVES To compare the global StrainCT with the change in electrical impedance (ΔZ). METHODS Acute respiratory distress syndrome patients under mechanical ventilation (VT 6 mL/kg ideal body weight with positive end-expiratory pressure 5 [PEEP 5] and best PEEP according to EIT) underwent whole-lung CT at end-inspiration and end-expiration. Biomechanical analysis was used to construct 3D maps and determine StrainCT at different levels of PEEP. CT and EIT acquisitions were performed simultaneously. Multilevel analysis was employed to determine the causal association between StrainCT and ΔZ. Linear regression models were used to predict the change in lung StrainCT between different PEEP levels based on the change in ΔZ. MAIN RESULTS StrainCT was positively and independently associated with ΔZ at global level (P < .01). Furthermore, the change in StrainCT (between PEEP 5 and Best PEEP) was accurately predicted by the change in ΔZ (R2 0.855, P < .001 at global level) with a high agreement between predicted and measured StrainCT . CONCLUSIONS The change in electrical impedance may provide a noninvasive assessment of global cyclic strain, without radiation at bedside.
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Affiliation(s)
- Rodrigo Cornejo
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
- Center of Acute Respiratory Critical Illness (ARCI) Santiago Chile
| | - Pablo Iturrieta
- Department of Structural and Geotechnical Engineering School of Engineering Pontificia Universidad Católica de Chile Santiago Chile
| | | | | | - Daniel Arellano
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
- Departamento de kinesiología Facultad de Medicina Universidad de Chile Santiago Chile
| | - Dannette Guiñez
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - María A. Cerda
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Roberto Brito
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Abraham I. J. Gajardo
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Marioli Lazo
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Lorena López
- Departamento de Radiología Hospital Clínico Universidad de Chile Santiago Chile
| | - Caio C. A. Morais
- Divisao de Pneumologia Faculdade de Medicina Instituto do Coracao Hospital das Clinicas HCFMUSP Universidade de Sao Paulo Sao Paulo Brazil
| | - Sedric González
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Miguel Zavala
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Verónica Rojas
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Juan N. Medel
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
| | - Daniel E. Hurtado
- Department of Structural and Geotechnical Engineering School of Engineering Pontificia Universidad Católica de Chile Santiago Chile
- Institute for Biological and Medical Engineering School of Engineering Pontificia Universidad Católica de Chile Santiago Chile
| | - Alejandro Bruhn
- Center of Acute Respiratory Critical Illness (ARCI) Santiago Chile
- Departamento de Medicina Intensiva Facultad de Medicina Pontificia Universidad Católica de Chile Santiago Chile
| | - Cristobal Ramos
- Departamento de Radiología Hospital Clínico Universidad de Chile Santiago Chile
| | - Nivia Estuardo
- Unidad de Pacientes Críticos Departamento de Medicina Hospital Clínico Universidad de Chile Santiago Chile
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23
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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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24
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Pourfathi M, Xin Y, Rosalino M, Cereda M, Kadlecek S, Duncan I, Profka H, Hamedani H, Siddiqui S, Ruppert K, Chatterjee S, Rizi RR. Pulmonary pyruvate metabolism as an index of inflammation and injury in a rat model of acute respiratory distress syndrome. NMR IN BIOMEDICINE 2020; 33:e4380. [PMID: 32681670 DOI: 10.1002/nbm.4380] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 06/15/2020] [Accepted: 06/29/2020] [Indexed: 06/11/2023]
Abstract
Increased pulmonary lactate production is correlated with severity of lung injury and outcome in acute respiratory distress syndrome (ARDS) patients. This study was conducted to investigate the relative contributions of inflammation and hypoxia to the lung's metabolic shift to glycolysis in an experimental animal model of ARDS using hyperpolarized (HP) 13 C MRI. Fifty-three intubated and mechanically ventilated male rats were imaged using HP 13 C MRI before, and 1, 2.5 and 4 hours after saline (sham) or hydrochloric acid (HCl; 0.5 ml/kg) instillation in the trachea, followed by protective and nonprotective mechanical ventilation (HCl-PEEP and HCl-ZEEP) or the start of moderate or severe hypoxia (Hyp90 and Hyp75 groups). Pulmonary and cardiac HP lactate-to-pyruvate ratios were compared among groups for different time points. Postmortem histology and immunofluorescence were used to assess lung injury severity and quantify the expression of innate inflammatory markers and local tissue hypoxia. HP pulmonary lactate-to-pyruvate ratio progressively increased in rats with lung injury and moderate hypoxia (HCl-ZEEP), with no significant change in pulmonary lactate-to-pyruvate ratio in noninjured but moderately hypoxic rats (Hyp90). Pulmonary lactate-to-pyruvate ratio was elevated in otherwise healthy lung tissue only in severe systemic hypoxia (Hyp75 group). ex vivo histological and immunopathological assessment further confirmed the link between elevated glycolysis and the recruitment into and presence of activated neutrophils in injured lungs. HP lactate-to-pyruvate ratio is elevated in injured lungs predominantly as a result of increased glycolysis in activated inflammatory cells, but can also increase due to severe inflammation-induced hypoxia.
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Affiliation(s)
- Mehrdad Pourfathi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yi Xin
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Michael Rosalino
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Maurizio Cereda
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stephen Kadlecek
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ian Duncan
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Harrilla Profka
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Hooman Hamedani
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Sarmad Siddiqui
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kai Ruppert
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Shampa Chatterjee
- Department of Physiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Rahim R Rizi
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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25
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Yen S, Song Y, Preissner M, Bennett E, Wilson R, Pavez M, Dubsky S, Dargaville PA, Fouras A, Zosky GR. The proteomic response is linked to regional lung volumes in ventilator-induced lung injury. J Appl Physiol (1985) 2020; 129:837-845. [PMID: 32758039 DOI: 10.1152/japplphysiol.00097.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
It is unclear how acid-induced lung injury alters the regional lung volume response to mechanical ventilation (MV) and how this impacts protein expression. Using a mouse model, we investigated the separate and combined effects of acid aspiration and MV on regional lung volumes and how these were associated with the proteome. Adult BALB/c mice were divided into four groups: intratracheal saline, intratracheal acid, saline/MV, or acid/MV. Specific tidal volume (sVt) and specific end-expiratory volume (sEEV) were measured at baseline and after 2 h of ventilation using dynamic high-resolution four-dimensional computed tomography (4DCT) images. Lung tissue was dissected into 10 regions corresponding to the image segmentation for label-free quantitative proteomic analysis. Our data showed that acid aspiration significantly reduced sVt and caused further reductions in sVt and sEEV after 2 h of ventilation. Proteomic analysis revealed 42 dysregulated proteins in both Saline/MV and Acid/MV groups, and 37 differentially expressed proteins in the Acid/MV group. Mapping of the overlapping proteins showed significant enrichment of complement/coagulation cascades (CCC). Analysis of 37 unique proteins in the Acid/MV group identified six additional CCC proteins and seven downregulated proteins involved in the mitochondrial respiratory chain (MRC). Regional MRC protein levels were positively correlated with sEEV, while the CCC protein levels were negatively associated with sVt. Therefore, this study showed that tidal volume was associated with the expression of CCC proteins, while low end-expiratory lung volumes were associated with MRC protein expression, suggesting that tidal stretch and lung collapse activate different injury pathways.NEW & NOTEWORTHY This study provides novel insights into the regional response to mechanical ventilation in the setting of acid-induced lung injury and highlights the complex interaction between tidal stretch and low-end-expiratory lung volumes; both of which caused altered regulation of different injury pathways.
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Affiliation(s)
- Seiha Yen
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Yong Song
- Menzies Institute for Medical Research, 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
| | - Richard Wilson
- Central Science Laboratory, University of Tasmania, Hobart, Tasmania, Australia
| | - Macarena Pavez
- Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Stephen Dubsky
- 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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26
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Albert K, Krischer JM, Pfaffenroth A, Wilde S, Lopez-Rodriguez E, Braun A, Smith BJ, Knudsen L. Hidden Microatelectases Increase Vulnerability to Ventilation-Induced Lung Injury. Front Physiol 2020; 11:530485. [PMID: 33071807 PMCID: PMC7530907 DOI: 10.3389/fphys.2020.530485] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 08/28/2020] [Indexed: 11/13/2022] Open
Abstract
Mechanical ventilation of lungs suffering from microatelectases may trigger the development of acute lung injury (ALI). Direct lung injury by bleomycin results in surfactant dysfunction and microatelectases at day 1 while tissue elastance and oxygenation remain normal. Computational simulations of alveolar micromechanics 1-day post-bleomycin predict persisting microatelectases throughout the respiratory cycle and increased alveolar strain during low positive end-expiratory pressure (PEEP) ventilation. As such, we hypothesize that mechanical ventilation in presence of microatelectases, which occur at low but not at higher PEEP, aggravates and unmasks ALI in the bleomycin injury model. Rats were randomized and challenged with bleomycin (B) or not (H = healthy). One day after bleomycin instillation the animals were ventilated for 3 h with PEEP 1 (PEEP1) or 5 cmH2O (PEEP5) and a tidal volume of 10 ml/kg bodyweight. Tissue elastance was repetitively measured after a recruitment maneuver to investigate the degree of distal airspace instability. The right lung was subjected to bronchoalveolar lavage (BAL), the left lung was fixed for design-based stereology at light- and electron microscopic level. Prior to mechanical ventilation, lung tissue elastance did not differ. During mechanical ventilation tissue elastance increased in bleomycin-injured lungs ventilated with PEEP = 1 cmH2O but remained stable in all other groups. Measurements at the conclusion of ventilation showed the largest time-dependent increase in tissue elastance after recruitment in B/PEEP1, indicating increased instability of distal airspaces. These lung mechanical findings correlated with BAL measurements including elevated BAL neutrophilic granulocytes as well as BAL protein and albumin in B/PEEP1. Moreover, the increased septal wall thickness and volume of peri-bronchiolar-vascular connective tissue in B/PEEP1 suggested aggravation of interstitial edema by ventilation in presence of microatelectases. At the electron microscopic level, the largest surface area of injured alveolar epithelial was observed in bleomycin-challenged lungs after PEEP = 1 cmH2O ventilation. After bleomycin treatment cellular markers of endoplasmic reticulum stress (p-Perk and p-EIF-2α) were positive within the septal wall and ventilation with PEEP = 1 cmH2O ventilation increased the surface area stained positively for p-EIF-2α. In conclusion, hidden microatelectases are linked with an increased pulmonary vulnerability for mechanical ventilation characterized by an aggravation of epithelial injury.
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Affiliation(s)
- Karolin Albert
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany
| | - Jeanne-Marie Krischer
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany
| | - Alexander Pfaffenroth
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany
| | - Sabrina Wilde
- Fraunhofer Institute for Toxicology and Experimental Medicine, Hanover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hanover, Germany
| | - Elena Lopez-Rodriguez
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hanover, Germany.,Institute for Functional Anatomy, Charité, Berlin, Germany
| | - Armin Braun
- Fraunhofer Institute for Toxicology and Experimental Medicine, Hanover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hanover, Germany
| | - Bradford J Smith
- Department of Bioengineering, College of Engineering, Design and Computing, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, United States
| | - Lars Knudsen
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hanover, Germany.,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hanover, Germany
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27
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Tucci MR, Pereira SM, Costa ELV, Vieira JE. Mechanical ventilation during thoracic surgery: towards individualized medicine. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:842. [PMID: 32793686 DOI: 10.21037/atm-20-2005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mauro Roberto Tucci
- Divisao de Pneumologia, Instituto do Coracao, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, São Paulo, Brazil
| | - Sérgio Martins Pereira
- Divisao de Pneumologia, Instituto do Coracao, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, São Paulo, Brazil
| | - Eduardo Leite Vieira Costa
- Divisao de Pneumologia, Instituto do Coracao, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, São Paulo, Brazil.,Instituto de Ensino e Pesquisa, Hospital Sírio Libanes, São Paulo, Brazil
| | - Joaquim Edson Vieira
- Disciplina de Anestesiologia, Departamento de Cirurgia, Faculdade de Medicina, Universidade de Sao Paulo, São Paulo, Brazil
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28
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Hurtado DE, Erranz B, Lillo F, Sarabia-Vallejos M, Iturrieta P, Morales F, Blaha K, Medina T, Diaz F, Cruces P. Progression of regional lung strain and heterogeneity in lung injury: assessing the evolution under spontaneous breathing and mechanical ventilation. Ann Intensive Care 2020; 10:107. [PMID: 32761387 PMCID: PMC7407426 DOI: 10.1186/s13613-020-00725-0] [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: 01/02/2020] [Accepted: 07/30/2020] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Protective mechanical ventilation (MV) aims at limiting global lung deformation and has been associated with better clinical outcomes in acute respiratory distress syndrome (ARDS) patients. In ARDS lungs without MV support, the mechanisms and evolution of lung tissue deformation remain understudied. In this work, we quantify the progression and heterogeneity of regional strain in injured lungs under spontaneous breathing and under MV. METHODS Lung injury was induced by lung lavage in murine subjects, followed by 3 h of spontaneous breathing (SB-group) or 3 h of low Vt mechanical ventilation (MV-group). Micro-CT images were acquired in all subjects at the beginning and at the end of the ventilation stage following induction of lung injury. Regional strain, strain progression and strain heterogeneity were computed from image-based biomechanical analysis. Three-dimensional regional strain maps were constructed, from which a region-of-interest (ROI) analysis was performed for the regional strain, the strain progression, and the strain heterogeneity. RESULTS After 3 h of ventilation, regional strain levels were significantly higher in 43.7% of the ROIs in the SB-group. Significant increase in regional strain was found in 1.2% of the ROIs in the MV-group. Progression of regional strain was found in 100% of the ROIs in the SB-group, whereas the MV-group displayed strain progression in 1.2% of the ROIs. Progression in regional strain heterogeneity was found in 23.4% of the ROIs in the SB-group, while the MV-group resulted in 4.7% of the ROIs showing significant changes. Deformation progression is concurrent with an increase of non-aerated compartment in SB-group (from 13.3% ± 1.6% to 37.5% ± 3.1%), being higher in ventral regions of the lung. CONCLUSIONS Spontaneous breathing in lung injury promotes regional strain and strain heterogeneity progression. In contrast, low Vt MV prevents regional strain and heterogeneity progression in injured lungs.
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Affiliation(s)
- Daniel E Hurtado
- Department of Structural and Geotechnical Engineering, School of Engineering Pontificia, Universidad Católica de Chile, Santiago, Chile.,Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Millennium Nucleus for Cardiovascular Magnetic Resonance, Santiago, Chile
| | - Benjamín Erranz
- Centro de Medicina Regenerativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Felipe Lillo
- Centro de Investigación de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Mauricio Sarabia-Vallejos
- Department of Structural and Geotechnical Engineering, School of Engineering Pontificia, Universidad Católica de Chile, Santiago, Chile
| | - Pablo Iturrieta
- Department of Structural and Geotechnical Engineering, School of Engineering Pontificia, Universidad Católica de Chile, Santiago, Chile
| | - Felipe Morales
- Centro de Investigación de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Katherine Blaha
- Pediatric Critical Care Unit, Clínica Alemana de Santiago, Santiago, Chile
| | - Tania Medina
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Franco Diaz
- Centro de Medicina Regenerativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Pediatric Critical Care Unit, Clínica Alemana de Santiago, Santiago, Chile
| | - Pablo Cruces
- Centro de Investigación de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile. .,Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile.
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29
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Argalious MY, Mao G, Davison RK, Chow C, Bhavani S. Association of Intraoperative Tidal Volumes and Acute Kidney Injury After Noncardiac Surgery. Anesth Analg 2020; 130:925-932. [DOI: 10.1213/ane.0000000000004254] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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30
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Individualized Positive End-expiratory Pressure and Regional Gas Exchange in Porcine Lung Injury. Anesthesiology 2020; 132:808-824. [DOI: 10.1097/aln.0000000000003151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Abstract
Background
In acute respiratory failure elevated intraabdominal pressure aggravates lung collapse, tidal recruitment, and ventilation inhomogeneity. Low positive end-expiratory pressure (PEEP) may promote lung collapse and intrapulmonary shunting, whereas high PEEP may increase dead space by inspiratory overdistension. The authors hypothesized that an electrical impedance tomography–guided PEEP approach minimizing tidal recruitment improves regional ventilation and perfusion matching when compared to a table-based low PEEP/no recruitment and an oxygenation-guided high PEEP/full recruitment strategy in a hybrid model of lung injury and elevated intraabdominal pressure.
Methods
In 15 pigs with oleic acid–induced lung injury intraabdominal pressure was increased by intraabdominal saline infusion. PEEP was set in randomized order: (1) guided by a PEEP/inspired oxygen fraction table, without recruitment maneuver; (2) minimizing tidal recruitment guided by electrical impedance tomography after a recruitment maneuver; and (3) maximizing oxygenation after a recruitment maneuver. Single photon emission computed tomography was used to analyze regional ventilation, perfusion, and aeration. Primary outcome measures were differences in PEEP levels and regional ventilation/perfusion matching.
Results
Resulting PEEP levels were different (mean ± SD) with (1) table PEEP: 11 ± 3 cm H2O; (2) minimal tidal recruitment PEEP: 22 ± 3 cm H2O; and (3) maximal oxygenation PEEP: 25 ± 4 cm H2O; P < 0.001. Table PEEP without recruitment maneuver caused highest lung collapse (28 ± 11% vs. 5 ± 5% vs. 4 ± 4%; P < 0.001), shunt perfusion (3.2 ± 0.8 l/min vs. 1.0 ± 0.8 l/min vs. 0.7 ± 0.6 l/min; P < 0.001) and dead space ventilation (2.9 ± 1.0 l/min vs. 1.5 ± 0.7 l/min vs. 1.7 ± 0.8 l/min; P < 0.001). Although resulting in different PEEP levels, minimal tidal recruitment and maximal oxygenation PEEP, both following a recruitment maneuver, had similar effects on regional ventilation/perfusion matching.
Conclusions
When compared to table PEEP without a recruitment maneuver, both minimal tidal recruitment PEEP and maximal oxygenation PEEP following a recruitment maneuver decreased shunting and dead space ventilation, and the effects of minimal tidal recruitment PEEP and maximal oxygenation PEEP were comparable.
Editor’s Perspective
What We Already Know about This Topic
What This Article Tells Us That Is New
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31
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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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32
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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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Herrmann J, Gerard SE, Shao W, Hawley ML, Reinhardt JM, Christensen GE, Hoffman EA, Kaczka DW. Quantifying Regional Lung Deformation Using Four-Dimensional Computed Tomography: A Comparison of Conventional and Oscillatory Ventilation. Front Physiol 2020; 11:14. [PMID: 32153417 PMCID: PMC7044245 DOI: 10.3389/fphys.2020.00014] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 01/13/2020] [Indexed: 01/14/2023] Open
Abstract
Mechanical ventilation strategies that reduce the heterogeneity of regional lung stress and strain may reduce the risk of ventilator-induced lung injury (VILI). In this study, we used registration of four-dimensional computed tomographic (4DCT) images to assess regional lung aeration and deformation in 10 pigs under baseline conditions and following acute lung injury induced with oleic acid. CT images were obtained via dynamic axial imaging (Siemens SOMATOM Force) during conventional pressure-controlled mechanical ventilation (CMV), as well as high-frequency and multi-frequency oscillatory ventilation modalities (HFOV and MFOV, respectively). Our results demonstrate that oscillatory modalities reduce intratidal strain throughout the lung in comparison to conventional ventilation, as well as the spatial gradients of dynamic strain along the dorsal-ventral axis. Harmonic distortion of parenchymal deformation was observed during HFOV with a single discrete sinusoid delivered at the airway opening, suggesting inherent mechanical nonlinearity of the lung tissues. MFOV may therefore provide improved lung-protective ventilation by reducing strain magnitudes and spatial gradients of strain compared to either CMV or HFOV.
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Affiliation(s)
- Jacob Herrmann
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA, United States.,Department of Anesthesia, University of Iowa, Iowa City, IA, United States.,OscillaVent, Inc., Iowa City, IA, United States
| | - Sarah E Gerard
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA, United States
| | - Wei Shao
- Department of Electrical and Computer Engineering, University of Iowa, Iowa City, IA, United States
| | | | - Joseph M Reinhardt
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA, United States.,Department of Radiology, University of Iowa, Iowa City, IA, United States
| | - Gary E Christensen
- Department of Electrical and Computer Engineering, University of Iowa, Iowa City, IA, United States.,Department of Radiation Oncology, University of Iowa, Iowa City, IA, United States
| | - Eric A Hoffman
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA, United States.,Department of Radiology, University of Iowa, Iowa City, IA, United States.,Department of Internal Medicine, University of Iowa, Iowa City, IA, United States
| | - David W Kaczka
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA, United States.,Department of Anesthesia, University of Iowa, Iowa City, IA, United States.,OscillaVent, Inc., Iowa City, IA, United States.,Department of Radiology, University of Iowa, Iowa City, IA, United States
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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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35
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Yen S, Preissner M, Bennett E, Dubsky S, Carnibella R, O'Toole R, Roddam L, Jones H, Dargaville PA, Fouras A, Zosky GR. The Link between Regional Tidal Stretch and Lung Injury during Mechanical Ventilation. Am J Respir Cell Mol Biol 2019; 60:569-577. [PMID: 30428271 DOI: 10.1165/rcmb.2018-0143oc] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The aim of this study was to assess the association between regional tidal volume (Vt), regional functional residual capacity (FRC), and the expression of genes linked with ventilator-induced lung injury. Two groups of BALB/c mice (n = 8 per group) were ventilated for 2 hours using a protective or injurious ventilation strategy, with free-breathing mice used as control animals. Regional Vt and FRC of the ventilated mice was determined by analysis of high-resolution four-dimensional computed tomographic images taken at baseline and after 2 hours of ventilation and corrected for the volume of the region (i.e., specific [s]Vt and specific [s]FRC). RNA concentrations of 21 genes in 10 different lung regions were quantified using a quantitative PCR array. sFRC at baseline varied regionally, independent of ventilation strategy, whereas sVt varied regionally depending on ventilation strategy. The expression of IL-6 (P = 0.04), Ccl2 (P < 0.01), and Ang-2 (P < 0.05) was associated with sVt but not sFRC. The expression of seven other genes varied regionally (IL-1β and RAGE [receptor for advanced glycation end products]) or depended on ventilation strategy (Nfe2l2 [nuclear factor erythroid-derived 2 factor 2], c-fos, and Wnt1) or both (TNF-α and Cxcl2), but it was not associated with regional sFRC or sVt. These observations suggest that regional inflammatory responses to mechanical ventilation are driven primarily by tidal stretch.
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Affiliation(s)
| | - Melissa Preissner
- 2 Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, Victoria, Australia
| | | | - Stephen Dubsky
- 2 Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, Victoria, Australia
| | | | | | | | - Heather Jones
- 4 Biomedical Imaging Research Institute.,5 Department of Medicine, and.,6 Women's Guild Lung Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - Peter A Dargaville
- 7 Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | | | - Graeme R Zosky
- 1 School of Medicine and.,7 Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
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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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Cruces P, Erranz B, Lillo F, Sarabia-Vallejos MA, Iturrieta P, Morales F, Blaha K, Medina T, Diaz F, Hurtado DE. Mapping regional strain in anesthetised healthy subjects during spontaneous ventilation. BMJ Open Respir Res 2019; 6:e000423. [PMID: 31749967 PMCID: PMC6830454 DOI: 10.1136/bmjresp-2019-000423] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 09/17/2019] [Accepted: 10/09/2019] [Indexed: 01/03/2023] Open
Abstract
Introduction Breathing produces a phenomenon of cyclic deformation throughout life. Biomechanically, deformation of the lung is measured as strain. Regional strain recently started to be recognised as a tool in the study of lung pathophysiology, but regional lung strain has not been studied in healthy subjects breathing spontaneously without voluntary or pharmacological control of ventilation. Our aim is to generate three-dimensional (3D) regional strain and heterogeneity maps of healthy rat lungs and describe their changes over time. Methods Micro-CT and image-based biomechanical analysis by finite element approach were carried out in six anaesthetised rats under spontaneous breathing in two different states, at the beginning of the experiment and after 3 hours of observation. 3D regional strain maps were constructed and divided into 10 isovolumetric region-of-interest (ROI) in three directions (apex to base, dorsal to ventral and costal to mediastinal), allowing to regionally analyse the volumetric strain, the strain progression and the strain heterogeneity. To describe in depth these parameters, and systematise their report, we defined regional strain heterogeneity index [1+strain SD ROI(x)]/[1+strain mean ROI(x)] and regional strain progression index [ROI(x)-mean of final strain/ROI(x)-mean of initial strain]. Results We were able to generate 3D regional strain maps of the lung in subjects without respiratory support, showing significant differences among the three analysed axes. We observed a significantly lower regional volumetric strain in the apex sector compared with the base, with no significant anatomical systematic differences in the other directions. This heterogeneity could not be identified with physiological or standard CT methods. There was no progression of the analysed regional volumetric strain when the two time-points were compared. Discussion It is possible to map the regional volumetric strain in the lung for healthy subjects during spontaneous breathing. Regional strain heterogeneity and changes over time can be measured using a CT image-based numerical analysis applying a finite element approach. These results support that healthy lung might have significant regional strain and its spatial distribution is highly heterogeneous. This protocol for CT image acquisition and analysis could be a useful tool for helping to understand the mechanobiology of the lung in many diseases.
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Affiliation(s)
- Pablo Cruces
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile.,Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Benjamin Erranz
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Felipe Lillo
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | | | - Pablo Iturrieta
- Pediatric Intensive Care Unit, Hospital Padre Hurtado, Santiago, Chile
| | - Felipe Morales
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Katherine Blaha
- Pediatric Intensive Care Unit, Hospital Clínico La Florida Dra. Eloisa Diaz Insunza, Santiago, Chile
| | - Tania Medina
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Franco Diaz
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile.,Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Millennium Nucleus for Cardiovascular Magnetic Resonance, Santiago, Chile
| | - Daniel E Hurtado
- Pediatric Intensive Care Unit, Hospital Padre Hurtado, Santiago, Chile.,Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Structural and Geotechnical Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
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Does Regional Lung Strain Correlate With Regional Inflammation in Acute Respiratory Distress Syndrome During Nonprotective Ventilation? An Experimental Porcine Study. Crit Care Med 2019. [PMID: 29528946 DOI: 10.1097/ccm.0000000000003072] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
OBJECTIVE It is known that ventilator-induced lung injury causes increased pulmonary inflammation. It has been suggested that one of the underlying mechanisms may be strain. The aim of this study was to investigate whether lung regional strain correlates with regional inflammation in a porcine model of acute respiratory distress syndrome. DESIGN Retrospective analysis of CT images and positron emission tomography images using [F]fluoro-2-deoxy-D-glucose. SETTING University animal research laboratory. SUBJECTS Seven piglets subjected to experimental acute respiratory distress syndrome and five ventilated controls. INTERVENTIONS Acute respiratory distress syndrome was induced by repeated lung lavages, followed by 210 minutes of injurious mechanical ventilation using low positive end-expiratory pressures (mean, 4 cm H2O) and high inspiratory pressures (mean plateau pressure, 45 cm H2O). All animals were subsequently studied with CT scans acquired at end-expiration and end-inspiration, to obtain maps of volumetric strain (inspiratory volume - expiratory volume)/expiratory volume, and dynamic positron emission tomography imaging. Strain maps and positron emission tomography images were divided into 10 isogravitational horizontal regions-of-interest, from which spatial correlation was calculated for each animal. MEASUREMENTS AND MAIN RESULTS The acute respiratory distress syndrome model resulted in a decrease in respiratory system compliance (20.3 ± 3.4 to 14.0 ± 4.9 mL/cm H2O; p < 0.05) and oxygenation (PaO2/FIO2, 489 ± 80 to 92 ± 59; p < 0.05), whereas the control animals did not exhibit changes. In the acute respiratory distress syndrome group, strain maps showed a heterogeneous distribution with a greater concentration in the intermediate gravitational regions, which was similar to the distribution of [F]fluoro-2-deoxy-D-glucose uptake observed in the positron emission tomography images, resulting in a positive spatial correlation between both variables (median R = 0.71 [0.02-0.84]; p < 0.05 in five of seven animals), which was not observed in the control animals. CONCLUSION In this porcine acute respiratory distress syndrome model, regional lung strain was spatially correlated with regional inflammation, supporting that strain is a relevant and prominent determinant of ventilator-induced lung injury.
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Follow the Voxel-A New Method for the Analysis of Regional Strain in Lung Injury. Crit Care Med 2019; 46:1033-1035. [PMID: 29762413 DOI: 10.1097/ccm.0000000000003109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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40
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Motta-Ribeiro GC, Hashimoto S, Winkler T, Baron RM, Grogg K, Paula LFSC, Santos A, Zeng C, Hibbert K, Harris RS, Bajwa E, Vidal Melo MF. Deterioration of Regional Lung Strain and Inflammation during Early Lung Injury. Am J Respir Crit Care Med 2019; 198:891-902. [PMID: 29787304 DOI: 10.1164/rccm.201710-2038oc] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
RATIONALE The contribution of aeration heterogeneity to lung injury during early mechanical ventilation of uninjured lungs is unknown. OBJECTIVES To test the hypotheses that a strategy consistent with clinical practice does not protect from worsening in lung strains during the first 24 hours of ventilation of initially normal lungs exposed to mild systemic endotoxemia in supine versus prone position, and that local neutrophilic inflammation is associated with local strain and blood volume at global strains below a proposed injurious threshold. METHODS Voxel-level aeration and tidal strain were assessed by computed tomography in sheep ventilated with low Vt and positive end-expiratory pressure while receiving intravenous endotoxin. Regional inflammation and blood volume were estimated from 2-deoxy-2-[(18)F]fluoro-d-glucose (18F-FDG) positron emission tomography. MEASUREMENTS AND MAIN RESULTS Spatial heterogeneity of aeration and strain increased only in supine lungs (P < 0.001), with higher strains and atelectasis than prone at 24 hours. Absolute strains were lower than those considered globally injurious. Strains redistributed to higher aeration areas as lung injury progressed in supine lungs. At 24 hours, tissue-normalized 18F-FDG uptake increased more in atelectatic and moderately high-aeration regions (>70%) than in normally aerated regions (P < 0.01), with differential mechanistically relevant regional gene expression. 18F-FDG phosphorylation rate was associated with strain and blood volume. Imaging findings were confirmed in ventilated patients with sepsis. CONCLUSIONS Mechanical ventilation consistent with clinical practice did not generate excessive regional strain in heterogeneously aerated supine lungs. However, it allowed worsening of spatial strain distribution in these lungs, associated with increased inflammation. Our results support the implementation of early aeration homogenization in normal lungs.
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Affiliation(s)
- Gabriel C Motta-Ribeiro
- 1 Department of Anesthesia, Critical Care and Pain Medicine.,2 Biomedical Engineering Program, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Soshi Hashimoto
- 1 Department of Anesthesia, Critical Care and Pain Medicine.,3 Department of Anesthesiology and Intensive Care, Kyoto Prefectural University of Medicine, Kyoto, Japan; and
| | - Tilo Winkler
- 1 Department of Anesthesia, Critical Care and Pain Medicine
| | - Rebecca M Baron
- 4 Department of Medicine (Pulmonary and Critical Care), Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | | | | | - Arnoldo Santos
- 1 Department of Anesthesia, Critical Care and Pain Medicine.,6 CIBER de Enfermedades Respiratorias, Madrid, Spain
| | - Congli Zeng
- 1 Department of Anesthesia, Critical Care and Pain Medicine
| | - Kathryn Hibbert
- 7 Department of Medicine (Pulmonary and Critical Care), Massachusetts General Hospital, and
| | - Robert S Harris
- 7 Department of Medicine (Pulmonary and Critical Care), Massachusetts General Hospital, and
| | - Ednan Bajwa
- 7 Department of Medicine (Pulmonary and Critical Care), Massachusetts General Hospital, and
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A Window on the Lung: Molecular Imaging as a Tool to Dissect Pathophysiologic Mechanisms of Acute Lung Disease. CONTRAST MEDIA & MOLECULAR IMAGING 2019; 2019:1510507. [PMID: 31531003 PMCID: PMC6732639 DOI: 10.1155/2019/1510507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/08/2019] [Indexed: 11/21/2022]
Abstract
In recent years, imaging has given a fundamental contribution to our understanding of the pathophysiology of acute lung diseases. Several methods have been developed based on computed tomography (CT), positron emission tomography (PET), and magnetic resonance (MR) imaging that allow regional, in vivo measurement of variables such as lung strain, alveolar size, metabolic activity of inflammatory cells, ventilation, and perfusion. Because several of these methods are noninvasive, they can be successfully translated from animal models to patients. The aim of this paper is to review the advances in knowledge that have been accrued with these imaging modalities on the pathophysiology of acute respiratory distress syndrome (ARDS), ventilator-induced lung injury (VILI), asthma and chronic obstructive pulmonary disease (COPD).
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42
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Herrmann J, Tawhai MH, Kaczka DW. Computational Modeling of Primary Blast Lung Injury: Implications for Ventilator Management. Mil Med 2019; 184:273-281. [PMID: 30901433 DOI: 10.1093/milmed/usy305] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 09/27/2018] [Accepted: 10/18/2018] [Indexed: 01/02/2023] Open
Abstract
Primary blast lung injury (PBLI) caused by exposure to high-intensity pressure waves is associated with parenchymal tissue injury and severe ventilation-perfusion mismatch. Although supportive ventilation is often required in patients with PBLI, maldistribution of gas flow in mechanically heterogeneous lungs may lead to further injury due to increased parenchymal strain and strain rate, which are difficult to predict in vivo. In this study, we developed a computational lung model with mechanical properties consistent with healthy and PBLI conditions. PBLI conditions were simulated with bilateral derecruitment and increased perihilar tissue stiffness. As a result of these tissue abnormalities, airway flow was heterogeneously distributed in the model under PBLI conditions, during both conventional mechanical ventilation (CMV) and high-frequency oscillatory ventilation. PBLI conditions resulted in over three-fold higher parenchymal strains compared to the healthy condition during CMV, with flow distributed according to regional tissue stiffness. During high-frequency oscillatory ventilation, flow distribution became increasingly heterogeneous and frequency-dependent. We conclude that the distribution and rate of parenchymal distension during mechanical ventilation depend on PBLI severity as well as ventilatory modality. These simulations may allow realistic assessment of the risks associated with ventilator-induced lung injury following PBLI, and facilitate the development of alternative lung-protective ventilation modalities.
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Affiliation(s)
- Jacob Herrmann
- Department of Anesthesia, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, Iowa City, IA.,Department of Biomedical Engineering, University of Iowa, 5601 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA
| | - Merryn H Tawhai
- Auckland Bioengineering Institute, University of Auckland, 6/70 Symonds St, Grafton, Auckland 1010, New Zealand
| | - David W Kaczka
- Department of Anesthesia, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, Iowa City, IA.,Department of Biomedical Engineering, University of Iowa, 5601 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA.,Department of Radiology, University of Iowa Hospitals and Clinics, 3970 John Pappajohn Pavilion, 200 Hawkins Dr, Iowa City, IA
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43
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Williams EC, Motta-Ribeiro GC, Vidal Melo MF. Driving Pressure and Transpulmonary Pressure: How Do We Guide Safe Mechanical Ventilation? Anesthesiology 2019; 131:155-163. [PMID: 31094753 PMCID: PMC6639048 DOI: 10.1097/aln.0000000000002731] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The physiological concept, pathophysiological implications and clinical relevance and application of driving pressure and transpulmonary pressure to prevent ventilator-induced lung injury are discussed.
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Affiliation(s)
- Elizabeth C Williams
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts. Current Affiliation: Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland (E.C.W.)
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Wang L, Cao Y, Gorshkov B, Zhou Y, Yang Q, Xu J, Ma Q, Zhang X, Wang J, Mao X, Zeng X, Su Y, Verin AD, Hong M, Liu Z, Huo Y. Ablation of endothelial Pfkfb3 protects mice from acute lung injury in LPS-induced endotoxemia. Pharmacol Res 2019; 146:104292. [PMID: 31167111 DOI: 10.1016/j.phrs.2019.104292] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/15/2019] [Accepted: 05/30/2019] [Indexed: 12/29/2022]
Abstract
Acute lung injury (ALI) is one of the leading causes of death in sepsis. Endothelial inflammation and dysfunction play a prominent role in development of ALI. Glycolysis is the predominant bioenergetic pathway for endothelial cells (ECs). However, the role of EC glycolysis in ALI of sepsis remains unclear. Here we show that both the expression and activity of PFKFB3, a key glycolytic activator, were markedly increased in lipopolysaccharide (LPS)-treated human pulmonary arterial ECs (HPAECs) in vitro and in lung ECs of mice challenged with LPS in vivo. PFKFB3 knockdown significantly reduced LPS-enhanced glycolysis in HPAECs. Compared with LPS-challenged wild-type mice, endothelial-specific Pfkfb3 knockout (Pfkfb3ΔVEC) mice exhibited reduced endothelium permeability, lower pulmonary edema, and higher survival rate. This was accompanied by decreased expression of intracellular adhesion molecule-1 (Icam-1) and vascular cell adhesion molecule 1 (Vcam-1), as well as decreased neutrophil and macrophage infiltration to the lung. Consistently, PFKFB3 silencing or PFKFB3 inhibition in HPAECs and human pulmonary microvascular ECs (HPMVECs) significantly downregulated LPS-induced expression of ICAM-1 and VCAM-1, and monocyte adhesion to human pulmonary ECs. In contrast, adenovirus-mediated PFKFB3 overexpression upregulated ICAM-1 and VCAM-1 expression in HPAECs. Mechanistically, PFKFB3 silencing suppressed LPS-induced nuclear translocation of nuclear factor κB (NF-κB)-p65, and NF-κB inhibitors abrogated PFKFB3-induced expression of ICAM-1 and VCAM-1. Finally, administration of the PFKFB3 inhibitor 3PO also reduced the inflammatory response of vascular endothelium and protected mice from LPS-induced ALI. Overall, these findings suggest that targeting PFKFB3-mediated EC glycolysis is an efficient therapeutic strategy for ALI in sepsis.
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Affiliation(s)
- Lina Wang
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Yapeng Cao
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - B Gorshkov
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Yaqi Zhou
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Qiuhua Yang
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Jiean Xu
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Qian Ma
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Xiaoyu Zhang
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Jingjing Wang
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xiaoxiao Mao
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Xianqiu Zeng
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yunchao Su
- Department of Pharmacology & Toxicology, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - A D Verin
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Mei Hong
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Zhiping Liu
- Drug Discovery Center, State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.
| | - Yuqing Huo
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.
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Varghese J, Hammel JM, Ibrahimiye AN, Siecke R, Bisselou Moukagna KS, Kutty S. Outcomes related to immediate extubation after stage 1 Norwood palliation for hypoplastic left heart syndrome. J Thorac Cardiovasc Surg 2019; 157:1591-1598. [DOI: 10.1016/j.jtcvs.2018.10.153] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 10/22/2018] [Accepted: 10/24/2018] [Indexed: 10/27/2022]
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Motta-Ribeiro G, Winkler T, Hashimoto S, Vidal Melo MF. Spatial Heterogeneity of Lung Strain and Aeration and Regional Inflammation During Early Lung Injury Assessed with PET/CT. Acad Radiol 2019; 26:313-325. [PMID: 30057194 PMCID: PMC6612262 DOI: 10.1016/j.acra.2018.02.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/20/2018] [Accepted: 02/27/2018] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Spatial heterogeneity of lung aeration and strain (change volume/resting volume) occurs at microscopic levels and contributes to lung injury. Yet, it is mostly assessed with histograms or large regions-of-interest. Spatial heterogeneity could also influence regional gene expression. We used positron emission tomography (PET)/computed tomography (CT) to assess the contribution of different length-scales to mechanical heterogeneity and to direct lung injury biological pathway identification. MATERIALS AND METHODS Sheep exposed to mild (n = 5, supine and n = 3, prone) and moderate (n = 6, supine) systemic endotoxemia were protectively ventilated. At baseline, 6 hours and 20 hours length-scale analysis was applied to aeration in CT (mild groups) and PET transmission (moderate group) scans; and voxel-level strain derived from image registration of end-inspiratory and end-expiratory CTs (mild). 2-deoxy-2-[(18)F]fluoro-d-glucose (18F-FDG)-PET kinetics parameters in ventral and dorsal regions were correlated with tissue microarray gene expression (moderate). RESULTS While aeration and strain heterogeneity were highest at 5-10 mm length-scales, larger length-scales contained a higher fraction of strain than aeration heterogeneity. Contributions of length-scales >5-10 mm to aeration and strain heterogeneity increased as lung injury progressed (p < 0.001) and were higher in supine than prone animals. Genes expressed with regional correlation to 18F-FDG-PET kinetics (|r| = 0.81 [0.78-0.85]) yielded pathways associated with immune system activation and fluid clearance. CONCLUSION Normal spatial heterogeneity of aeration and strain suggest larger anatomical and functional determinants of lung strain than aeration heterogeneity. Lung injury and supine position increase the contribution of larger length-scales. 18F-FDG-PET-based categorization of gene expression results in known and novel biological pathways relevant to lung injury.
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Affiliation(s)
- Gabriel Motta-Ribeiro
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114.
| | - Tilo Winkler
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114.
| | - Soshi Hashimoto
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114.
| | - Marcos F Vidal Melo
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, 55 Fruit St, Boston, MA 02114.
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Increased 90-Day Mortality in Spontaneously Breathing Patients With Paraquat Poisoning. Crit Care Med 2019; 47:219-228. [DOI: 10.1097/ccm.0000000000003518] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Knudsen L, Lopez-Rodriguez E, Berndt L, Steffen L, Ruppert C, Bates JHT, Ochs M, Smith BJ. Alveolar Micromechanics in Bleomycin-induced Lung Injury. Am J Respir Cell Mol Biol 2018; 59:757-769. [PMID: 30095988 PMCID: PMC6293074 DOI: 10.1165/rcmb.2018-0044oc] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 06/29/2018] [Indexed: 12/22/2022] Open
Abstract
Lung injury results in intratidal alveolar recruitment and derecruitment and alveolar collapse, creating stress concentrators that increase strain and aggravate injury. In this work, we sought to describe alveolar micromechanics during mechanical ventilation in bleomycin-induced lung injury and surfactant replacement therapy. Structure and function were assessed in rats 1 day and 3 days after intratracheal bleomycin instillation and after surfactant replacement therapy. Pulmonary system mechanics were measured during ventilation with positive end-expiratory pressures (PEEPs) between 1 and 10 cm H2O, followed by perfusion fixation at end-expiratory pressure at airway opening (Pao) values of 1, 5, 10, and 20 cm H2O for quantitative analyses of lung structure. Lung structure and function were used to parameterize a physiologically based, multicompartment computational model of alveolar micromechanics. In healthy controls, the numbers of open alveoli remained stable in a range of Pao = 1-20 cm H2O, whereas bleomycin-challenged lungs demonstrated progressive alveolar derecruitment with Pao < 10 cm H2O. At Day 3, ∼40% of the alveoli remained closed at high Pao, and alveolar size heterogeneity increased. Simulations of injured lungs predicted that alveolar recruitment pressures were much greater than the derecruitment pressures, so that minimal intratidal recruitment and derecruitment occurred during mechanical ventilation with a tidal volume of 10 ml/kg body weight over a range of PEEPs. However, the simulations also predicted a dramatic increase in alveolar strain with injury that we attribute to alveolar interdependence. These findings suggest that in progressive lung injury, alveolar collapse with increased distension of patent (open) alveoli dominates alveolar micromechanics. PEEP and surfactant substitution reduce alveolar collapse and dynamic strain but increase static strain.
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Affiliation(s)
- Lars Knudsen
- Institute of Functional and Applied Anatomy, and
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research (DZL) Hannover Medical School, Hannover, Germany
- REBIRTH, Cluster of Excellence, Hannover, Germany
| | - Elena Lopez-Rodriguez
- Institute of Functional and Applied Anatomy, and
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research (DZL) Hannover Medical School, Hannover, Germany
- REBIRTH, Cluster of Excellence, Hannover, Germany
| | | | | | - Clemens Ruppert
- Department of Internal Medicine, and
- Universities of Giessen and Marburg Lung Center, Member of the German Center for Lung Research (DZL), Justus Liebig University Giessen, Giessen, Germany
| | | | - Matthias Ochs
- Institute of Functional and Applied Anatomy, and
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover, Member of the German Center for Lung Research (DZL) Hannover Medical School, Hannover, Germany
- REBIRTH, Cluster of Excellence, Hannover, Germany
| | - Bradford J. Smith
- Department of Bioengineering, University of Colorado Denver, Denver, Colorado
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Bates JHT, Smith BJ. Ventilator-induced lung injury and lung mechanics. ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:378. [PMID: 30460252 PMCID: PMC6212358 DOI: 10.21037/atm.2018.06.29] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/11/2018] [Indexed: 02/03/2023]
Abstract
Mechanical ventilation applies physical stresses to the tissues of the lung and thus may give rise to ventilator-induced lung injury (VILI), particular in patients with acute respiratory distress syndrome (ARDS). The most dire consequences of VILI result from injury to the blood-gas barrier. This allows plasma-derived fluid and proteins to leak into the airspaces where they flood some alveolar regions, while interfering with the functioning of pulmonary surfactant in those regions that remain open. These effects are reflected in commensurately increased values of dynamic lung elastance (EL ), a quantity that in principle is readily measured at the bedside. Recent mathematical/computational modeling studies have shown that the way in which EL varies as a function of both time and positive end-expiratory pressure (PEEP) reflects the nature and degree of lung injury, and can even be used to infer the separate contributions of volutrauma and atelectrauma to VILI. Interrogating such models for minimally injurious regimens of mechanical ventilation that apply to a particular lung may thus lead to personalized approaches to the ventilatory management of ARDS.
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Affiliation(s)
- Jason H. T. Bates
- Department of Medicine, University of Vermont Larner College of Medicine, Burlington, VT, USA
| | - Bradford J. Smith
- Department of Bioengineering, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
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Fernandez-Bustamante A, Vidal Melo MF. Bedside assessment of lung aeration and stretch. Br J Anaesth 2018; 121:1001-1004. [PMID: 30336843 PMCID: PMC8604375 DOI: 10.1016/j.bja.2018.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 08/06/2018] [Accepted: 08/09/2018] [Indexed: 11/18/2022] Open
Affiliation(s)
- A Fernandez-Bustamante
- Department of Anesthesiology, University of Colorado School of Medicine, Aurora, CO, USA; Webb Waring Center, University of Colorado School of Medicine, Aurora, CO, USA
| | - M F Vidal Melo
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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