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Murgolo F, Grieco DL, Spadaro S, Bartolomeo N, di Mussi R, Pisani L, Fiorentino M, Crovace AM, Lacitignola L, Staffieri F, Grasso S. Recruitment-to-inflation ratio reflects the impact of peep on dynamic lung strain in a highly recruitable model of ARDS. Ann Intensive Care 2024; 14:106. [PMID: 38963617 PMCID: PMC11224186 DOI: 10.1186/s13613-024-01343-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 06/21/2024] [Indexed: 07/05/2024] Open
Abstract
BACKGROUND The recruitment-to-inflation ratio (R/I) has been recently proposed to bedside assess response to PEEP. The impact of PEEP on ventilator-induced lung injury depends on the extent of dynamic strain reduction. We hypothesized that R/I may reflect the potential for lung recruitment (i.e. recruitability) and, consequently, estimate the impact of PEEP on dynamic lung strain, both assessed through computed tomography scan. METHODS Fourteen lung-damaged pigs (lipopolysaccharide infusion) underwent ventilation at low (5 cmH2O) and high PEEP (i.e., PEEP generating a plateau pressure of 28-30 cmH2O). R/I was measured through a one-breath derecruitment maneuver from high to low PEEP. PEEP-induced changes in dynamic lung strain, difference in nonaerated lung tissue weight (tissue recruitment) and amount of gas entering previously nonaerated lung units (gas recruitment) were assessed through computed tomography scan. Tissue and gas recruitment were normalized to the weight and gas volume of previously ventilated lung areas at low PEEP (normalized-tissue recruitment and normalized-gas recruitment, respectively). RESULTS Between high (median [interquartile range] 20 cmH2O [18-21]) and low PEEP, median R/I was 1.08 [0.88-1.82], indicating high lung recruitability. Compared to low PEEP, tissue and gas recruitment at high PEEP were 246 g [182-288] and 385 ml [318-668], respectively. R/I was linearly related to normalized-gas recruitment (r = 0.90; [95% CI 0.71 to 0.97) and normalized-tissue recruitment (r = 0.69; [95% CI 0.25 to 0.89]). Dynamic lung strain was 0.37 [0.29-0.44] at high PEEP and 0.59 [0.46-0.80] at low PEEP (p < 0.001). R/I was significantly related to PEEP-induced reduction in dynamic (r = - 0.93; [95% CI - 0.78 to - 0.98]) and global lung strain (r = - 0.57; [95% CI - 0.05 to - 0.84]). No correlation was found between R/I and and PEEP-induced changes in static lung strain (r = 0.34; [95% CI - 0.23 to 0.74]). CONCLUSIONS In a highly recruitable ARDS model, R/I reflects the potential for lung recruitment and well estimates the extent of PEEP-induced reduction in dynamic lung strain.
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Affiliation(s)
- Francesco Murgolo
- Department of Precision-Regenerative Medicine and Jonic Area (DiMePRe-J), Section of Anesthesiology and Intensive Care Medicine, University of Bari "Aldo Moro", Bari, Italy.
- Dipartimento di Medicina di Precisione e Rigenerativa e Area Jonica (DiMePRe-J), Sezione di Anestesiologia e Rianimazione, Ospedale Policlinico, Università Degli Studi "Aldo Moro", Piazza Giulio Cesare 11, Bari, Italy.
| | - Domenico L Grieco
- Department of Anesthesia, Intensive Care and Emergency, Fondazione Policlinico A. Gemelli IRCCS, Rome, Italy
- Department of Anesthesiology and Intensive Care Medicine, Catholic University of the Sacred Heart, Rome, Italy
| | - Savino Spadaro
- Department of Translational Medicine, Section of Anesthesiology and Intensive Care Medicine, University of Ferrara, Ferrara, Italy
| | - Nicola Bartolomeo
- Interdisciplinary Department of Medicine, University of Bari "Aldo Moro", Bari, Italy
| | - Rossella di Mussi
- Department of Precision-Regenerative Medicine and Jonic Area (DiMePRe-J), Section of Anesthesiology and Intensive Care Medicine, University of Bari "Aldo Moro", Bari, Italy
| | - Luigi Pisani
- Department of Precision-Regenerative Medicine and Jonic Area (DiMePRe-J), Section of Anesthesiology and Intensive Care Medicine, University of Bari "Aldo Moro", Bari, Italy
| | - Marco Fiorentino
- Nephrology, Dialysis and Transplantation Unit, Department of Precision and Regenerative Medicine and Ionian Area (DiMePRe-J), University of Bari, Bari, Italy
| | | | - Luca Lacitignola
- Department of Precision-Regenerative Medicine and Jonic Area (DiMePRe-J), Section of Veterinary Medicine, University of Bari "Aldo Moro", Bari, Italy
| | - Francesco Staffieri
- Department of Precision-Regenerative Medicine and Jonic Area (DiMePRe-J), Section of Veterinary Medicine, University of Bari "Aldo Moro", Bari, Italy
| | - Salvatore Grasso
- Department of Precision-Regenerative Medicine and Jonic Area (DiMePRe-J), Section of Anesthesiology and Intensive Care Medicine, University of Bari "Aldo Moro", Bari, Italy
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Nunnally ME. Invited Commentary: The Stress Index. J Cardiothorac Vasc Anesth 2024:S1053-0770(24)00376-8. [PMID: 38918096 DOI: 10.1053/j.jvca.2024.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Accepted: 06/03/2024] [Indexed: 06/27/2024]
Affiliation(s)
- Mark E Nunnally
- Departments of Anesthesia, Perioperative Care and Pain Medicine, Neurology, Surgery, and Medicine, NYU School of Medicine, New York, NY
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3
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Schwartz EA, Chow B, Bronshteyn YS, Young CC. Ventilator Stress Index: An Intensive Care Unit Tool That Anesthesiologists Should Know. J Cardiothorac Vasc Anesth 2024:S1053-0770(24)00348-3. [PMID: 38918098 DOI: 10.1053/j.jvca.2024.05.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 05/16/2024] [Indexed: 06/27/2024]
Affiliation(s)
- Evan A Schwartz
- Division of Pulmonary, Allergy, and Critical Care, Duke University Medical Center, Durham, NC; Department of Internal Medicine, Duke University Medical Center, Durham, NC.
| | - Bryan Chow
- Department of Internal Medicine, Duke University Medical Center, Durham, NC; Division of Adult Cardiothoracic Anesthesiology, Duke University Medical Center, Durham, NC; Department of Anesthesiology, Duke University Medical Center, Durham, NC
| | - Yuriy S Bronshteyn
- Department of Internal Medicine, Duke University Medical Center, Durham, NC; Department of Anesthesiology, Duke University Medical Center, Durham, NC; Duke University School of Medicine, Durham, NC; Durham VA Health Care System, Durham, NC
| | - Christopher C Young
- Department of Internal Medicine, Duke University Medical Center, Durham, NC; Department of Anesthesiology, Duke University Medical Center, Durham, NC; Division of Adult Critical Care Anesthesia, Duke University Medical Center, Durham, NC
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4
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Agrawal DK, Smith BJ, Sottile PD, Hripcsak G, Albers DJ. Quantifiable identification of flow-limited ventilator dyssynchrony with the deformed lung ventilator model. Comput Biol Med 2024; 173:108349. [PMID: 38547660 DOI: 10.1016/j.compbiomed.2024.108349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 03/13/2024] [Accepted: 03/17/2024] [Indexed: 04/17/2024]
Abstract
BACKGROUND Ventilator dyssynchrony (VD) can worsen lung injury and is challenging to detect and quantify due to the complex variability in the dyssynchronous breaths. While machine learning (ML) approaches are useful for automating VD detection from the ventilator waveform data, scalable severity quantification and its association with pathogenesis and ventilator mechanics remain challenging. OBJECTIVE We develop a systematic framework to quantify pathophysiological features observed in ventilator waveform signals such that they can be used to create feature-based severity stratification of VD breaths. METHODS A mathematical model was developed to represent the pressure and volume waveforms of individual breaths in a feature-based parametric form. Model estimates of respiratory effort strength were used to assess the severity of flow-limited (FL)-VD breaths compared to normal breaths. A total of 93,007 breath waveforms from 13 patients were analyzed. RESULTS A novel model-defined continuous severity marker was developed and used to estimate breath phenotypes of FL-VD breaths. The phenotypes had a predictive accuracy of over 97% with respect to the previously developed ML-VD identification algorithm. To understand the incidence of FL-VD breaths and their association with the patient state, these phenotypes were further successfully correlated with ventilator-measured parameters and electronic health records. CONCLUSION This work provides a computational pipeline to identify and quantify the severity of FL-VD breaths and paves the way for a large-scale study of VD causes and effects. This approach has direct application to clinical practice and in meaningful knowledge extraction from the ventilator waveform data.
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Affiliation(s)
- Deepak K Agrawal
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, 400076, India; Department of Bioengineering, University of Colorado Denver | Anschutz Medical Campus, Aurora, CO, 80045, USA.
| | - Bradford J Smith
- Department of Bioengineering, University of Colorado Denver | Anschutz Medical Campus, Aurora, CO, 80045, USA; Section of Pulmonary and Sleep Medicine, Department of Pediatrics, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Peter D Sottile
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - George Hripcsak
- Department of Biomedical Informatics, Columbia University, New York, NY, 10027, USA
| | - David J Albers
- Department of Bioengineering, University of Colorado Denver | Anschutz Medical Campus, Aurora, CO, 80045, USA; Department of Biomedical Informatics, Columbia University, New York, NY, 10027, USA; Department of Biomedical Informatics, Univerisity of Colorado Anschutz Medical Campus, Aurora, CO 80045.
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5
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Santos A, Monge-García MI, Borges JB, Retamal J, Tusman G, Larsson A, Suarez-Sipmann F. Impact of respiratory cycle during mechanical ventilation on beat-to-beat right ventricle stroke volume estimation by pulmonary artery pulse wave analysis. Intensive Care Med Exp 2024; 12:34. [PMID: 38592650 PMCID: PMC11004097 DOI: 10.1186/s40635-024-00618-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 03/28/2024] [Indexed: 04/10/2024] Open
Abstract
BACKGROUND The same principle behind pulse wave analysis can be applied on the pulmonary artery (PA) pressure waveform to estimate right ventricle stroke volume (RVSV). However, the PA pressure waveform might be influenced by the direct transmission of the intrathoracic pressure changes throughout the respiratory cycle caused by mechanical ventilation (MV), potentially impacting the reliability of PA pulse wave analysis (PAPWA). We assessed a new method that minimizes the direct effect of the MV on continuous PA pressure measurements and enhances the reliability of PAPWA in tracking beat-to-beat RVSV. METHODS Continuous PA pressure and flow were simultaneously measured for 2-3 min in 5 pigs using a high-fidelity micro-tip catheter and a transonic flow sensor around the PA trunk, both pre and post an experimental ARDS model. RVSV was estimated by PAPWA indexes such as pulse pressure (SVPP), systolic area (SVSystAUC) and standard deviation (SVSD) beat-to-beat from both corrected and non-corrected PA signals. The reference RVSV was derived from the PA flow signal (SVref). RESULTS The reliability of PAPWA in tracking RVSV on a beat-to-beat basis was enhanced after accounting for the direct impact of intrathoracic pressure changes induced by MV throughout the respiratory cycle. This was evidenced by an increase in the correlation between SVref and RVSV estimated by PAPWA under healthy conditions: rho between SVref and non-corrected SVSD - 0.111 (0.342), corrected SVSD 0.876 (0.130), non-corrected SVSystAUC 0.543 (0.141) and corrected SVSystAUC 0.923 (0.050). Following ARDS, correlations were SVref and non-corrected SVSD - 0.033 (0.262), corrected SVSD 0.839 (0.077), non-corrected SVSystAUC 0.483 (0.114) and corrected SVSystAUC 0.928 (0.026). Correction also led to reduced limits of agreement between SVref and SVSD and SVSystAUC in the two evaluated conditions. CONCLUSIONS In our experimental model, we confirmed that correcting for mechanical ventilation induced changes during the respiratory cycle improves the performance of PAPWA for beat-to-beat estimation of RVSV compared to uncorrected measurements. This was demonstrated by a better correlation and agreement between the actual SV and the obtained from PAPWA.
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Affiliation(s)
- Arnoldo Santos
- Intensive Care Medicine Department. Hospital, Universitario Fundación Jiménez Díaz. IIS-FJD, Madrid, Spain.
- CIBER de Enfermedades Respiratorias CIBERES ISCIII, Madrid, Spain.
- Universidad Alfonso X El Sabio, Madrid, Spain.
| | - M Ignacio Monge-García
- Unidad de Cuidados Críticos, Hospital Universitario SAS de Jerez, Jerez de La Frontera, Spain
| | - João Batista Borges
- First Faculty of Medicine, Institute of Physiology, Charles University, Prague, Czechia
| | - Jaime Retamal
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gerardo Tusman
- Department of Anesthesia, Hospital Privado de Comunidad, Mar del Plata, Argentina
| | - Anders Larsson
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Fernando Suarez-Sipmann
- CIBER de Enfermedades Respiratorias CIBERES ISCIII, Madrid, Spain
- Department of Critical Care, Hospital Universitario de la Princesa, Madrid, Spain
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Kummer RL, Marini JJ. The Respiratory Mechanics of COVID-19 Acute Respiratory Distress Syndrome-Lessons Learned? J Clin Med 2024; 13:1833. [PMID: 38610598 PMCID: PMC11012401 DOI: 10.3390/jcm13071833] [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: 01/31/2024] [Revised: 03/13/2024] [Accepted: 03/18/2024] [Indexed: 04/14/2024] Open
Abstract
Acute respiratory distress syndrome (ARDS) is a well-defined clinical entity characterized by the acute onset of diffuse pulmonary injury and hypoxemia not explained by fluid overload. The COVID-19 pandemic brought about an unprecedented volume of patients with ARDS and challenged our understanding and clinical approach to treatment of this clinical syndrome. Unique to COVID-19 ARDS is the disruption and dysregulation of the pulmonary vascular compartment caused by the SARS-CoV-2 virus, which is a significant cause of hypoxemia in these patients. As a result, gas exchange does not necessarily correlate with respiratory system compliance and mechanics in COVID-19 ARDS as it does with other etiologies. The purpose of this review is to relate the mechanics of COVID-19 ARDS to its underlying pathophysiologic mechanisms and outline the lessons we have learned in the management of this clinic syndrome.
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Affiliation(s)
- Rebecca L. Kummer
- Department of Pulmonary and Critical Care Medicine, University of Minnesota School of Medicine, Minneapolis, MN 55455, USA
| | - John J. Marini
- Department of Pulmonary and Critical Care Medicine, Regions Hospital, St. Paul, MN 55101, USA
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7
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Mammel MC. Evolution of mechanical ventilation of the newborn infant. Semin Perinatol 2024; 48:151884. [PMID: 38555220 DOI: 10.1016/j.semperi.2024.151884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
Artificial ventilation of the newborn infant is the foundation of neonatology. Early practitioners included pediatricians, anesthesiologists, cardiologists, respiratory therapists, and engineers. The discovery of surfactant, followed by the death of Patrick Kennedy, jump-started the new area, with investment and research rapidly expanding. The ever more complex design of mechanical ventilators necessitated a more thorough understanding of newborn pulmonary physiology in order to provide support with minimal associated injury. This piece briefly reviews and highlights this history.
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Affiliation(s)
- Mark C Mammel
- Professor of Pediatrics, University of Minnesota, Minneapolis, MN 55455, United States.
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8
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Mojoli F, Pozzi M, Arisi E. Setting positive end-expiratory pressure: using the pressure-volume curve. Curr Opin Crit Care 2024; 30:35-42. [PMID: 38085871 DOI: 10.1097/mcc.0000000000001127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
PURPOSE OF REVIEW To discuss the role of pressure-volume curve (PV curve) in exploring elastic properties of the respiratory system and setting mechanical ventilator to reduce ventilator-induced lung injury. RECENT FINDINGS Nowadays, quasi-static PV curves and loops can be easily obtained and analyzed at the bedside without disconnection of the patient from the ventilator. It is shown that this tool can provide useful information to optimize ventilator setting. For example, PV curves can assess for patient's individual potential for lung recruitability and also evaluate the risk for lung injury of the ongoing mechanical ventilation setting. SUMMARY In conclusion, PV curve is an easily available bedside tool: its correct interpretation can be extremely valuable to enlighten potential for lung recruitability and select a high or low positive end-expiratory pressure (PEEP) strategy. Furthermore, recent studies have shown that PV curve can play a significant role in PEEP and driving pressure fine tuning: clinical studies are needed to prove whether this technique will improve outcome.
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Affiliation(s)
- Francesco Mojoli
- Department of Clinical-Surgical, Diagnostic and Pediatric Sciences, Unit of Anesthesia and Intensive Care, University of Pavia, Pavia, Italy
- Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Marco Pozzi
- Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Eric Arisi
- Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
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9
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Collins PD, Giosa L, Camporota L, Barrett NA. State of the art: Monitoring of the respiratory system during veno-venous extracorporeal membrane oxygenation. Perfusion 2024; 39:7-30. [PMID: 38131204 DOI: 10.1177/02676591231210461] [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] [Indexed: 12/23/2023]
Abstract
Monitoring the patient receiving veno-venous extracorporeal membrane oxygenation (VV ECMO) is challenging due to the complex physiological interplay between native and membrane lung. Understanding these interactions is essential to understand the utility and limitations of different approaches to respiratory monitoring during ECMO. We present a summary of the underlying physiology of native and membrane lung gas exchange and describe different tools for titrating and monitoring gas exchange during ECMO. However, the most important role of VV ECMO in severe respiratory failure is as a means of avoiding further ergotrauma. Although optimal respiratory management during ECMO has not been defined, over the last decade there have been advances in multimodal respiratory assessment which have the potential to guide care. We describe a combination of imaging, ventilator-derived or invasive lung mechanic assessments as a means to individualise management during ECMO.
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Affiliation(s)
- Patrick Duncan Collins
- Department of Critical Care Medicine, Guy's and St Thomas' National Health Service Foundation Trust, London, UK
- Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, King's College London, London, UK
| | - Lorenzo Giosa
- Department of Critical Care Medicine, Guy's and St Thomas' National Health Service Foundation Trust, London, UK
| | - Luigi Camporota
- Department of Critical Care Medicine, Guy's and St Thomas' National Health Service Foundation Trust, London, UK
- Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, King's College London, London, UK
| | - Nicholas A Barrett
- Department of Critical Care Medicine, Guy's and St Thomas' National Health Service Foundation Trust, London, UK
- Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, King's College London, London, UK
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Pearce AK, McGuire WC, Elliott AR, Goligher EC, Prisk GK, Butler JP, Malhotra A. Impact of Supine Versus Semirecumbent Body Posture on the Distribution of Ventilation in Acute Respiratory Distress Syndrome. Crit Care Explor 2023; 5:e1014. [PMID: 38053751 PMCID: PMC10695482 DOI: 10.1097/cce.0000000000001014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023] Open
Abstract
In some patients with acute respiratory distress syndrome (ARDS), a paradoxical improvement in respiratory system compliance (CRS) has been observed when assuming a supine (head of bed [HOB] 0°) compared with semirecumbent (HOB 35-40°) posture. We sought to test the hypothesis that mechanically ventilated patients with ARDS would have improved CRS, due to changes in ventilation distribution, when moving from the semirecumbent to supine position. We conducted a prospective, observational ICU study including 14 mechanically ventilated patients with ARDS. For each patient, ventilation distribution (assessed by electrical impedance tomography) and pulmonary mechanics were compared in supine versus semirecumbent postures. Compared with semirecumbent, in the supine posture CRS increased (33 ± 21 vs. 26 ± 14 mL/cm H2O, p = 0.005), driving pressure was reduced (14 ± 6 vs. 17 ± 7 cm H2O, p < 0.001), and dorsal fraction of ventilation was decreased (48.5 ± 14.1% vs. 54.5 ± 12.0%, p = 0.003). Posture change from semirecumbent to supine resulted in a favorable physiologic response in terms of improved CRS and reduced driving pressure-with a corresponding increase in ventral ventilation, possibly related to reduced ventral overdistension.
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Affiliation(s)
- Alex K Pearce
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, University of California San Diego, La Jolla, CA
| | - W Cameron McGuire
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, University of California San Diego, La Jolla, CA
| | - Ann R Elliott
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, University of California San Diego, La Jolla, CA
| | - Ewan C Goligher
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
- Department of Medicine, Division of Respirology, University Health Network, Toronto, ON, Canada
| | - G Kim Prisk
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, University of California San Diego, La Jolla, CA
| | - James P Butler
- Department of Environmental Health TH Chan School of Public Health, Boston, MA
| | - Atul Malhotra
- Division of Pulmonary, Critical Care, Sleep Medicine, and Physiology, University of California San Diego, La Jolla, CA
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11
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Zersen KM. Setting the optimal positive end-expiratory pressure: a narrative review. Front Vet Sci 2023; 10:1083290. [PMID: 37538169 PMCID: PMC10395088 DOI: 10.3389/fvets.2023.1083290] [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: 10/28/2022] [Accepted: 06/27/2023] [Indexed: 08/05/2023] Open
Abstract
The primary goals of positive end-expiratory pressure (PEEP) are to restore functional residual capacity through recruitment and prevention of alveolar collapse. Through these mechanisms, PEEP improves arterial oxygenation and may reduce the risk of ventilator-induced lung injury (VILI). Because of the many potential negative effects associated with the use of PEEP, much research has concentrated on determining the optimal PEEP setting. Arterial oxygenation targets and pressure-volume loops have been utilized to set the optimal PEEP for decades. Several other techniques have been suggested, including the use of PEEP tables, compliance, driving pressure (DP), stress index (SI), transpulmonary pressures, imaging, and electrical impedance tomography. Each of these techniques has its own benefits and limitations and there is currently not one technique that is recommended above all others.
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12
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Braithwaite SA, van Hooijdonk E, van der Kaaij NP. Ventilation during ex vivo lung perfusion, a review. Transplant Rev (Orlando) 2023; 37:100762. [PMID: 37099887 DOI: 10.1016/j.trre.2023.100762] [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: 11/21/2022] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 04/28/2023]
Abstract
Evidence suggests that ventilation during ex vivo lung perfusion (EVLP) with a 'one-size-fits-all' strategy has the potential to cause lung injury which may only become clinically relevant in marginal lung allografts. EVLP induced- or accelerated lung injury is a dynamic and cumulative process reflecting the interplay of a number of factors. Stress and strain in lung tissue caused by positive pressure ventilation may be exacerbated by the altered properties of lung tissue in an EVLP setting. Any pre-existing injury may alter the ability of lung allografts to accommodate set ventilation and perfusion techniques on EVLP leading to further injury. This review will examine the effects of ventilation on donor lungs in the setting of EVLP. A framework for developing a protective ventilation technique will be proposed.
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Affiliation(s)
- Sue A Braithwaite
- Department of Anesthesiology, University Medical Center Utrecht, Q04.2.317, Postbus 85500, Utrecht 3508, GA, the Netherlands.
| | - Elise van Hooijdonk
- Department of Cardiothoracic Surgery, University Medical Center Utrecht, Room E03.511, Heidelberglaan 100, Utrecht 3584, CX, the Netherlands
| | - Niels P van der Kaaij
- Department of Cardiothoracic Surgery, University Medical Center Utrecht, Room E03.511, Heidelberglaan 100, Utrecht 3584, CX, the Netherlands
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13
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Costamagna A, Steinberg I, Pivetta E, Arina P, Veglia S, Brazzi L, Fanelli V. Clinical performance of lung ultrasound in predicting time-dependent changes in lung aeration in ARDS patients. J Clin Monit Comput 2023; 37:473-480. [PMID: 35939164 PMCID: PMC9358118 DOI: 10.1007/s10877-022-00902-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 07/25/2022] [Indexed: 11/17/2022]
Abstract
To evaluate whether lung ultrasound is reliable bedside tool to monitor changes of lung aeration at the early and late stages of ARDS. LUS was performed in ARDS patients that underwent at least two consecutive CT scan at ICU admission and at least 1 week after admission. Twelve fields were evaluated and graded from 0 (normal) to 3 (consolidation). Changes of LUS score in twelve fields (ΔLUStot) and in four ventral (ΔLUSV), intermediate (ΔLUSI) and dorsal (ΔLUSD) zones were calculated at each time points. Three categories were described: Improve (ΔLUS < 0), Equal (ΔLUS = 0) or Worse (ΔLUS > 0). LUS scores were correlated with total changes in lung CT aeration (ΔCTair) and with normally, poorly and not aerated regions (ΔCTnorm, ΔCTpoor and ΔCTnot, respectively). Eleven patients were enrolled. ΔLUStot had significant correlation with ΔCTair (r = - 0.74, p < 0.01). ΔLUSV, ΔLUSI and ΔLUSD showed significant correlations with ΔCTair (r = - 0.66, r = - 0.69, r = - 0.63, respectively; p < 0.05). Compared to Equal, Improve and Worse categories had significantly higher (p < 0.01) and lower (p < 0.05) ΔCTair values, respectively. Compared to Equal, Improve and Worse categories had lower (p < 0.01) and higher (p < 0.01) ΔCTnot values, respectively. LUS score had a good correlation with lung CT in detecting changes of lung aeration.
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Affiliation(s)
- Andrea Costamagna
- Department of Anaesthesia and Critical Care, AOU Città Della Salute E Della Scienza Di Torino, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy
- Department of Surgical Sciences, University of Turin, Turin, Italy
| | - Irene Steinberg
- Department of Surgical Sciences, University of Turin, Turin, Italy
| | - Emanuele Pivetta
- Division of Emergency Medicine and High Dependency Unit, Department of Medical Sciences, AOU Città Della Salute E Della Scienza Di Torino, Turin, Italy
| | - Pietro Arina
- Division of Medicine, UCL, Bloomsbury Institute for Intensive Care Medicine, Gower street, London, UK
| | - Simona Veglia
- Department of Diagnostic Imaging and Radiotherapy, AOU Città Della Salute E Della Scienza Di Torino, University of Turin, Turin, Italy
| | - Luca Brazzi
- Department of Anaesthesia and Critical Care, AOU Città Della Salute E Della Scienza Di Torino, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy
- Department of Surgical Sciences, University of Turin, Turin, Italy
| | - Vito Fanelli
- Department of Anaesthesia and Critical Care, AOU Città Della Salute E Della Scienza Di Torino, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy.
- Department of Surgical Sciences, University of Turin, Turin, Italy.
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14
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Hennessey E, Bittner E, White P, Kovar A, Meuchel L. Intraoperative Ventilator Management of the Critically Ill Patient. Anesthesiol Clin 2023; 41:121-140. [PMID: 36871995 PMCID: PMC9985493 DOI: 10.1016/j.anclin.2022.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
Strategies for the intraoperative ventilator management of the critically ill patient focus on parameters used for lung protective ventilation with acute respiratory distress syndrome, preventing or limiting the deleterious effects of mechanical ventilation, and optimizing anesthetic and surgical conditions to limit postoperative pulmonary complications for patients at risk. Patient conditions such as obesity, sepsis, the need for laparoscopic surgery, or one-lung ventilation may benefit from intraoperative lung protective ventilation strategies. Anesthesiologists can use risk evaluation and prediction tools, monitor advanced physiologic targets, and incorporate new innovative monitoring techniques to develop an individualized approach for patients.
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Affiliation(s)
- Erin Hennessey
- Stanford University - School of Medicine Department of Anesthesiology, Perioperative and Pain Medicine, 300 Pasteur Drive, Room H3580, Stanford, CA 94305, USA.
| | - Edward Bittner
- Department of Anesthesia, Critical Care and Pain Medicine, Harvard Medical School, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Peggy White
- University of Florida College of Medicine, Department of Anesthesiology, 1500 SW Archer Road, PO Box 100254, Gainesville, FL 32610, USA
| | - Alan Kovar
- Oregon Health and Science University, 3161 SW Pavilion Loop, Portland, OR 97239, USA
| | - Lucas Meuchel
- Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
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15
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16
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Selickman J, Tawfik P, Crooke PS, Dries DJ, Shelver J, Gattinoni L, Marini JJ. Paradoxical response to chest wall loading predicts a favorable mechanical response to reduction in tidal volume or PEEP. Crit Care 2022; 26:201. [PMID: 35791021 PMCID: PMC9255488 DOI: 10.1186/s13054-022-04073-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 06/24/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Chest wall loading has been shown to paradoxically improve respiratory system compliance (CRS) in patients with moderate to severe acute respiratory distress syndrome (ARDS). The most likely, albeit unconfirmed, mechanism is relief of end-tidal overdistension in ‘baby lungs’ of low-capacity. The purpose of this study was to define how small changes of tidal volume (VT) and positive end-expiratory pressure (PEEP) affect CRS (and its associated airway pressures) in patients with ARDS who demonstrate a paradoxical response to chest wall loading. We hypothesized that small reductions of VT or PEEP would alleviate overdistension and favorably affect CRS and conversely, that small increases of VT or PEEP would worsen CRS.
Methods
Prospective, multi-center physiologic study of seventeen patients with moderate to severe ARDS who demonstrated paradoxical responses to chest wall loading. All patients received mechanical ventilation in volume control mode and were passively ventilated. Airway pressures were measured before and after decreasing/increasing VT by 1 ml/kg predicted body weight and decreasing/increasing PEEP by 2.5 cmH2O.
Results
Decreasing either VT or PEEP improved CRS in all patients. Driving pressure (DP) decreased by a mean of 4.9 cmH2O (supine) and by 4.3 cmH2O (prone) after decreasing VT, and by a mean of 2.9 cmH2O (supine) and 2.2 cmH2O (prone) after decreasing PEEP. CRS increased by a mean of 3.1 ml/cmH2O (supine) and by 2.5 ml/cmH2O (prone) after decreasing VT. CRS increased by a mean of 5.2 ml/cmH2O (supine) and 3.6 ml/cmH2O (prone) after decreasing PEEP (P < 0.01 for all). Small increments of either VT or PEEP worsened CRS in the majority of patients.
Conclusion
Patients with a paradoxical response to chest wall loading demonstrate uniform improvement in both DP and CRS following a reduction in either VT or PEEP, findings in keeping with prior evidence suggesting its presence is a sign of end-tidal overdistension. The presence of ‘paradox’ should prompt re-evaluation of modifiable determinants of end-tidal overdistension, including VT, PEEP, and body position.
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17
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Selickman J, Marini JJ. Chest wall loading in the ICU: pushes, weights, and positions. Ann Intensive Care 2022; 12:103. [PMID: 36346532 PMCID: PMC9640797 DOI: 10.1186/s13613-022-01076-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 10/20/2022] [Indexed: 11/11/2022] Open
Abstract
Clinicians monitor mechanical ventilatory support using airway pressures—primarily the plateau and driving pressure, which are considered by many to determine the safety of the applied tidal volume. These airway pressures are influenced not only by the ventilator prescription, but also by the mechanical properties of the respiratory system, which consists of the series-coupled lung and chest wall. Actively limiting chest wall expansion through external compression of the rib cage or abdomen is seldom performed in the ICU. Recent literature describing the respiratory mechanics of patients with late-stage, unresolving, ARDS, however, has raised awareness of the potential diagnostic (and perhaps therapeutic) value of this unfamiliar and somewhat counterintuitive practice. In these patients, interventions that reduce resting lung volume, such as loading the chest wall through application of external weights or manual pressure, or placing the torso in a more horizontal position, have unexpectedly improved tidal compliance of the lung and integrated respiratory system by reducing previously undetected end-tidal hyperinflation. In this interpretive review, we first describe underappreciated lung and chest wall interactions that are clinically relevant to both normal individuals and to the acutely ill who receive ventilatory support. We then apply these physiologic principles, in addition to published clinical observation, to illustrate the utility of chest wall modification for the purposes of detecting end-tidal hyperinflation in everyday practice.
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Affiliation(s)
- John Selickman
- grid.17635.360000000419368657Department of Pulmonary and Critical Care Medicine, University of Minnesota, Minneapolis, MN USA ,grid.415858.50000 0001 0087 6510Department of Critical Care Medicine, Regions Hospital, MS 11203B, 640 Jackson St., St. Paul, MN 55101-2595 USA
| | - John J. Marini
- grid.17635.360000000419368657Department of Pulmonary and Critical Care Medicine, University of Minnesota, Minneapolis, MN USA ,grid.415858.50000 0001 0087 6510Department of Critical Care Medicine, Regions Hospital, MS 11203B, 640 Jackson St., St. Paul, MN 55101-2595 USA
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18
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Bedside Detection of End-Tidal Hyperinflation in Acute Respiratory Distress Syndrome. Ann Am Thorac Soc 2022; 19:1791-1795. [PMID: 35849421 DOI: 10.1513/annalsats.202205-460ps] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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19
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Non-invasive over-distension measurements: data driven vs model-based. J Clin Monit Comput 2022; 37:389-398. [PMID: 35920951 DOI: 10.1007/s10877-022-00900-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 07/22/2022] [Indexed: 10/16/2022]
Abstract
Clinical measurements offer bedside monitoring aiming to minimise unintended over-distension, but have limitations and cannot be predicted for changes in mechanical ventilation (MV) settings and are only available in certain MV modes. This study introduces a non-invasive, real-time over-distension measurement, which is robust, predictable, and more intuitive than current methods. The proposed over-distension measurement, denoted as OD, is compared with the clinically proven stress index (SI). Correlation is analysed via R2 and Spearman rs. The OD safe range corresponding to the unit-less SI safe range (0.95-1.05) is calibrated by sensitivity and specificity test. Validation is fulfilled with 19 acute respiratory distress syndrome (ARDS) patients data (196 cases), including assessment across ARDS severity. Overall correlation between OD and SI yielded R2 = 0.76 and Spearman rs = 0.89. Correlation is higher considering only moderate and severe ARDS patients. Calibration of OD to SI yields a safe range defined: 0 ≤ OD ≤ 0.8 cmH2O. The proposed OD offers an efficient, general, real-time measurement of patient-specific lung mechanics, which is more intuitive and robust than SI. OD eliminates the limitations of SI in MV mode and its less intuitive lung status value. Finally, OD can be accurately predicted for new ventilator settings via its foundation in a validated predictive personalized lung mechanics model. Therefore, OD offers potential clinical value over current clinical methods.
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20
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Selickman J, Tawfik P, Crooke PS, Dries DJ, Shelver J, Gattinoni L, Marini JJ. Paradoxical response to chest wall loading predicts a favorable mechanical response to reduction in tidal volume or PEEP. Crit Care 2022. [PMID: 35791021 DOI: 10.1186/s13054-022-04073-] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
BACKGROUND Chest wall loading has been shown to paradoxically improve respiratory system compliance (CRS) in patients with moderate to severe acute respiratory distress syndrome (ARDS). The most likely, albeit unconfirmed, mechanism is relief of end-tidal overdistension in 'baby lungs' of low-capacity. The purpose of this study was to define how small changes of tidal volume (VT) and positive end-expiratory pressure (PEEP) affect CRS (and its associated airway pressures) in patients with ARDS who demonstrate a paradoxical response to chest wall loading. We hypothesized that small reductions of VT or PEEP would alleviate overdistension and favorably affect CRS and conversely, that small increases of VT or PEEP would worsen CRS. METHODS Prospective, multi-center physiologic study of seventeen patients with moderate to severe ARDS who demonstrated paradoxical responses to chest wall loading. All patients received mechanical ventilation in volume control mode and were passively ventilated. Airway pressures were measured before and after decreasing/increasing VT by 1 ml/kg predicted body weight and decreasing/increasing PEEP by 2.5 cmH2O. RESULTS Decreasing either VT or PEEP improved CRS in all patients. Driving pressure (DP) decreased by a mean of 4.9 cmH2O (supine) and by 4.3 cmH2O (prone) after decreasing VT, and by a mean of 2.9 cmH2O (supine) and 2.2 cmH2O (prone) after decreasing PEEP. CRS increased by a mean of 3.1 ml/cmH2O (supine) and by 2.5 ml/cmH2O (prone) after decreasing VT. CRS increased by a mean of 5.2 ml/cmH2O (supine) and 3.6 ml/cmH2O (prone) after decreasing PEEP (P < 0.01 for all). Small increments of either VT or PEEP worsened CRS in the majority of patients. CONCLUSION Patients with a paradoxical response to chest wall loading demonstrate uniform improvement in both DP and CRS following a reduction in either VT or PEEP, findings in keeping with prior evidence suggesting its presence is a sign of end-tidal overdistension. The presence of 'paradox' should prompt re-evaluation of modifiable determinants of end-tidal overdistension, including VT, PEEP, and body position.
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Affiliation(s)
- John Selickman
- Department of Pulmonary and Critical Care Medicine, University of Minnesota School of Medicine, 640 Jackson Street, Mail Stop 11203B, MinneapolisSt. Paul, MN, 55101, USA.
| | - Pierre Tawfik
- Department of Pulmonary and Critical Care Medicine, University of Minnesota School of Medicine, 640 Jackson Street, Mail Stop 11203B, MinneapolisSt. Paul, MN, 55101, USA
| | - Philip S Crooke
- Department of Mathematics, Vanderbilt University, Nashville, TN, USA
| | - David J Dries
- Department of Surgery, Regions Hospital, St Paul, MN, USA
- Department of Surgery, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Jonathan Shelver
- Department of Pulmonary and Critical Care Medicine, Methodist Hospital, St. Louis Park, MN, USA
| | - Luciano Gattinoni
- Department of Anesthesiology, Medical University of Göttingen, University Medical Center Göttingen, Göttingen, Germany
| | - John J Marini
- Department of Pulmonary and Critical Care Medicine, University of Minnesota School of Medicine, 640 Jackson Street, Mail Stop 11203B, MinneapolisSt. Paul, MN, 55101, USA
- Department of Critical Care Medicine, Regions Hospital, St. Paul, MN, USA
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21
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Rezoagli E, Laffey JG, Bellani G. Monitoring Lung Injury Severity and Ventilation Intensity during Mechanical Ventilation. Semin Respir Crit Care Med 2022; 43:346-368. [PMID: 35896391 DOI: 10.1055/s-0042-1748917] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Acute respiratory distress syndrome (ARDS) is a severe form of respiratory failure burden by high hospital mortality. No specific pharmacologic treatment is currently available and its ventilatory management is a key strategy to allow reparative and regenerative lung tissue processes. Unfortunately, a poor management of mechanical ventilation can induce ventilation induced lung injury (VILI) caused by physical and biological forces which are at play. Different parameters have been described over the years to assess lung injury severity and facilitate optimization of mechanical ventilation. Indices of lung injury severity include variables related to gas exchange abnormalities, ventilatory setting and respiratory mechanics, ventilation intensity, and the presence of lung hyperinflation versus derecruitment. Recently, specific indexes have been proposed to quantify the stress and the strain released over time using more comprehensive algorithms of calculation such as the mechanical power, and the interaction between driving pressure (DP) and respiratory rate (RR) in the novel DP multiplied by four plus RR [(4 × DP) + RR] index. These new parameters introduce the concept of ventilation intensity as contributing factor of VILI. Ventilation intensity should be taken into account to optimize protective mechanical ventilation strategies, with the aim to reduce intensity to the lowest level required to maintain gas exchange to reduce the potential for VILI. This is further gaining relevance in the current era of phenotyping and enrichment strategies in ARDS.
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Affiliation(s)
- Emanuele Rezoagli
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,Department of Emergency and Intensive Care, San Gerardo University Hospital, Monza, Italy
| | - John G Laffey
- School of Medicine, National University of Ireland, Galway, Ireland.,Department of Anaesthesia and Intensive Care Medicine, Galway University Hospitals, Saolta University Hospital Group, Galway, Ireland.,Lung Biology Group, Regenerative Medicine Institute (REMEDI) at CÚRAM Centre for Research in Medical Devices, National University of Ireland Galway, Galway, Ireland
| | - Giacomo Bellani
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,Department of Emergency and Intensive Care, San Gerardo University Hospital, Monza, Italy
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22
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Stepwise Ventilator Waveform Assessment to Diagnose Pulmonary Pathophysiology. Anesthesiology 2022; 137:85-92. [PMID: 35511174 DOI: 10.1097/aln.0000000000004220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Clinicians can use mechanical waveform analysis as a diagnostic tool to identify pulmonary pathophysiology. This review offers an approach to develop a hypothesis of a patient’s lung pathophysiology.
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23
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Effects of Prone Position on Lung Recruitment and Ventilation-Perfusion Matching in Patients With COVID-19 Acute Respiratory Distress Syndrome. Crit Care Med 2022; 50:723-732. [PMID: 35200194 PMCID: PMC9005091 DOI: 10.1097/ccm.0000000000005450] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Prone positioning allows to improve oxygenation and decrease mortality rate in COVID-19–associated acute respiratory distress syndrome (C-ARDS). However, the mechanisms leading to these effects are not fully understood. The aim of this study is to assess the physiologic effects of pronation by the means of CT scan and electrical impedance tomography (EIT).
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24
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Zivec K, Arnez T, Lovšin K, Kramaric A, Gradisek P, Mirkovic T. Successful outcome of inhalation injury, active SARS-CoV-2 infection and concomitant pneumonia in a patient with 27% full thickness burn: a case report. J Burn Care Res 2022; 43:749-752. [PMID: 35084502 PMCID: PMC8807314 DOI: 10.1093/jbcr/irac010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Burn injuries are a major cause of morbidity and mortality. Next to the inhalation injury, total body surface area and age are strong predictors of mortality in burn victims. The novel coronavirus disease (COVID-19) pandemic is associated with a fatality rate of around 3,5%. We present a case of burn victim with full thickness burn to face, scalp, both upper extremities (27% of total body surface area), inhalation injury and active SARS-CoV-2 infection with concomitant pneumonia. The inhalation injury in COVID-19 positive patient was severe. A bronchoscopy revealed a diffuse erythema of the trachea and both main bronchi, the whole bronchial tree up to the distal segments was covered with carbonaceous material which could not be removed. We decided to treat the inhalation injury according to the guidelines for burns and acute respiratory distress syndrome. Accordingly, the patient did not receive any antiviral drugs or corticosteroids. The reconstruction of a full-thickness scalp defect after burn presents a challenge in large size defects and in patients with comorbidities. Double layer Integra Dermal Regeneration Template (Integra LifeSciences, Plainsboro, New Jersey) was the reconstruction method of choice. The take of dermal template and split thickness skin graft was 100% and good scalp contour was achieved. To our knowledge this is the first case report presenting a successful treatment outcome in a burn victim with inhalation injury, active SARS-CoV-2 infection and concomitant pneumonia with full thickness burn of 27% of total body surface area.
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Affiliation(s)
- Katarina Zivec
- Department of Plastic, Reconstructive and Aesthetic Surgery and Burns, University Medical Center Ljubljana, Zaloska, Ljubljana, Slovenia
| | - Tine Arnez
- Department of Plastic, Reconstructive and Aesthetic Surgery and Burns, University Medical Center Ljubljana, Zaloska, Ljubljana, Slovenia
| | - Klemen Lovšin
- Department of Plastic, Reconstructive and Aesthetic Surgery and Burns, University Medical Center Ljubljana, Zaloska, Ljubljana, Slovenia
| | - Anja Kramaric
- Department of Anesthesiology and Surgical Intensive Care Therapy, University Medical Center Ljubljana, Zaloska, Ljubljana, Slovenia
| | - Primoz Gradisek
- Department of Anesthesiology and Surgical Intensive Care Therapy, University Medical Center Ljubljana, Zaloska, Ljubljana, Slovenia
| | - Tomislav Mirkovic
- Department of Anesthesiology and Surgical Intensive Care Therapy, University Medical Center Ljubljana, Zaloska, Ljubljana, Slovenia
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25
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Individualized positive end-expiratory pressure guided by end-expiratory lung volume in early acute respiratory distress syndrome: study protocol for the multicenter, randomized IPERPEEP trial. Trials 2022; 23:63. [PMID: 35057852 PMCID: PMC8772175 DOI: 10.1186/s13063-021-05993-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 12/30/2021] [Indexed: 12/16/2022] Open
Abstract
Background In acute respiratory distress syndrome (ARDS), response to positive end-expiratory pressure (PEEP) is variable according to different degrees of lung recruitability. The search for a tool to individualize PEEP based on patients’ individual response is warranted. End-expiratory lung volume (EELV) assessment by nitrogen washing-washout aids bedside estimation of PEEP-induced alveolar recruitment and may therefore help titrate PEEP on patient’s individual recruitability. We designed a randomized trial to test whether an individualized PEEP setting protocol driven by EELV measurement may improve a composite clinical outcome in patients with moderate-to-severe ARDS (IPERPEEP trial). Methods IPERPEEP is an open-label, multicenter, randomized trial that will be conducted in 10 intensive care units in Italy and will enroll 132 ARDS patients showing PaO2/FiO2 ratio ≤ 150 mmHg within 24 h from endotracheal intubation while on mechanical ventilation with PEEP 5 cmH2O. To standardize lung volumes at study initiation, all patients will undergo mechanical ventilation with tidal volume of 6 ml/kg of predicted body weight and PEEP set to obtain a plateau pressure within 28 and 30 cmH2O for 30 min (EXPRESS PEEP). Afterwards, a 5-step decremental PEEP trial will be conducted (EXPRESS PEEP to PEEP 5 cmH2O), and EELV will be measured at each step. Recruitment-to-inflation ratio will be calculated for each PEEP range from EELV difference. Patients will be then randomized to receive mechanical ventilation with PEEP set according to the optimal recruitment observed in the PEEP trial (IPERPEEP arm) trial or to achieve a plateau pressure of 28–30 cmH2O (control arm, EXPRESS strategy). In both groups, tidal volume size, use of prone positioning and neuromuscular blocking agents, and weaning from PEEP and from mechanical ventilation will be standardized. The primary endpoint of the study is a composite clinical outcome incorporating in-ICU mortality, 60-day ventilator-free days, and serum interleukin-6 concentration over the course of the initial 72 h of treatment. Discussion The IPERPEEP study is a randomized trial powered to elucidate whether an individualized PEEP setting protocol based on bedside assessment of lung recruitability can improve a composite clinical outcome during moderate-to-severe ARDS. Trial registration ClinicalTrials.govNCT04012073. Registered 9 July 2019. Supplementary Information The online version contains supplementary material available at 10.1186/s13063-021-05993-0.
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26
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Rollas K, Hanci P, Topeli A. Effects of end-expiratory lung volume versus PaO 2 guided PEEP determination on respiratory mechanics and oxygenation in moderate to severe ARDS. Exp Lung Res 2021; 48:12-22. [PMID: 34957895 DOI: 10.1080/01902148.2021.2021326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
There is no ideal method for determination of positive end-expiratory pressure (PEEP) in acute respiratory distress syndrome (ARDS) patients. We compared the effects of end-expiratory lung volume (EELV)-guided versus PaO2-guided PEEP determination on respiratory mechanics and oxygenation during the first 48 hours in moderate to severe ARDS. Twenty-two patients with moderate to severe ARDS admitted to an academic medical ICU were assigned to PaO2-guided (n = 11) or to EELV-guided PEEP determination (n = 11) group. First, an incremental PEEP trial was performed by increasing PEEP by 3 cmH2O steps from 8 to 20 cmH2O and in each step EELV and lung mechanics were measured in both groups. Then, oxygenation and respiratory mechanics were measured under the determined PEEP at 4, 12, 24, and 48th hours. After the incremental PEEP trial, over the 48 hours of the study period, in the EELV-guided group PaO2 and PaO2/FiO2 increased (p = 0.04 and p = 0.02; respectively), whereas they did not change in PaO2-guided group (p = 0.09 and p = 0.27; respectively). In all patients, the median value of EELV change (ΔEELV) during incremental PEEP trial was 25%. In patients with ΔEELV > 25% (n = 11) PaO2, PaO2/FiO2 and Cs increased over time in 48 hours (p = 0.03, p < 0.01, and p = 0.04; respectively), whereas they did not change in those with ΔEELV ≤ 25% (n = 11) (p = 0.73, p = 0.51, and p = 0.73; respectively). Compared to PaO2-guided PEEP determination, EELV-guided PEEP determination resulted in greater improvement in oxygenation over time. Patients who had > 25% improvement in EELV during a PEEP trial had greater improvement in oxygenation and compliance over 48 hours. Supplemental data for this article is available online at.
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Affiliation(s)
- Kazim Rollas
- Division of Intensive Care Medicine, Department of Anaesthesiology, Tepecik Training and Research Hospital, Izmir, Turkey
| | - Pervin Hanci
- Division of Intensive Care Medicine, Department of Pulmonology, Trakya University Faculty of Medicine, Edirne, Turkey
| | - Arzu Topeli
- Division of Intensive Care Medicine, Department of Internal Medicine, Faculty of Medicine, Hacettepe University, Ankara, Turkey
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Flow Index accurately identifies breaths with low or high inspiratory effort during pressure support ventilation. Crit Care 2021; 25:427. [PMID: 34911541 PMCID: PMC8672539 DOI: 10.1186/s13054-021-03855-4] [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: 08/04/2021] [Accepted: 12/03/2021] [Indexed: 01/19/2023] Open
Abstract
Background Flow Index, a numerical expression of the shape of the inspiratory flow-time waveform recorded during pressure support ventilation, is associated with patient inspiratory effort. The aim of this study was to assess the accuracy of Flow Index in detecting high or low inspiratory effort during pressure support ventilation and to establish cutoff values for the Flow index to identify these conditions. The secondary aim was to compare the performance of Flow index,of breathing pattern parameters and of airway occlusion pressure (P0.1) in detecting high or low inspiratory effort during pressure support ventilation. Methods Data from 24 subjects was included in the analysis, accounting for a total of 702 breaths. Breaths with high inspiratory effort were defined by a pressure developed by inspiratory muscles (Pmusc) greater than 10 cmH2O while breaths with low inspiratory effort were defined by a Pmusc lower than 5 cmH2O. The areas under the receiver operating characteristic curves of Flow Index and respiratory rate, tidal volume,respiratory rate over tidal volume and P0.1 were analyzed and compared to identify breaths with low or high inspiratory effort. Results Pmusc, P0.1, Pressure Time Product and Flow Index differed between breaths with high, low and intermediate inspiratory effort, while RR, RR/VT and VT/kg of IBW did not differ in a statistically significant way. A Flow index higher than 4.5 identified breaths with high inspiratory effort [AUC 0.89 (CI 95% 0.85–0.93)], a Flow Index lower than 2.6 identified breaths with low inspiratory effort [AUC 0.80 (CI 95% 0.76–0.83)]. Conclusions Flow Index is accurate in detecting high and low spontaneous inspiratory effort during pressure support ventilation. Supplementary Information The online version contains supplementary material available at 10.1186/s13054-021-03855-4.
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28
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Su PL, Lin WC, Ko YF, Cheng KS, Chen CW. Electrical Impedance Tomography Analysis Between Two Similar Respiratory System Compliance During Decremetal PEEP Titration in ARDS Patients. J Med Biol Eng 2021; 41:888-894. [PMID: 34803552 PMCID: PMC8593398 DOI: 10.1007/s40846-021-00668-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 10/21/2021] [Indexed: 12/16/2022]
Abstract
Purpose The positive end-expiratory pressure (PEEP) level with best respiratory system compliance (Crs) is frequently used for PEEP selection in acute respiratory distress syndrome (ARDS) patients. On occasion, two similar best Crs (where the difference between the Crs of two PEEP levels is < 1 ml/cm H2O) may be identified during decremental PEEP titration. Selecting PEEP under such conditions is challenging. The aim of this study was to provide supplementary rationale for PEEP selection by assessing the global and regional ventilation distributions between two PEEP levels in this situation. Methods Eight ARDS cases with similar best Crs at two different PEEP levels were analyzed using examination-specific electrical impedance tomography (EIT) measures and airway stress index (SIaw). Five Crs were measured at PEEP values of 25 cm H2O (PEEP25), 20 cm H2O (PEEP20), 15 cm H2O (PEEPH), 11 cm H2O (PEEPI), and 7 cm H2O (PEEPL). The higher PEEP value of the two PEEPs with similar best Crs was designated as PEEPupper, while the lower designated as PEEPlower. Results PEEPH and PEEPI shared the best Crs in two cases, while similar Crs was found at PEEPI and PEEPL in the remaining six cases. SIaw was higher with PEEPupper as compared to PEEPlower (1.06 ± 0.10 versus 0.99 ± 0.09, p = 0.05). Proportion of lung hyperdistension was significantly higher with PEEPupper than PEEPlower (7.0 ± 5.1% versus 0.3 ± 0.5%, p = 0.0002). In contrast, proportion of recruitable lung collapse was higher with PEEPlower than PEEPupper (18.6 ± 4.4% versus 5.9 ± 3.7%, p < 0.0001). Cyclic alveolar collapse and reopening during tidal breathing was higher at PEEPlower than PEEPupper (34.4 ± 19.3% versus 16.0 ± 9.1%, p = 0.046). The intratidal gas distribution (ITV) index was also significantly higher at PEEPlower than PEEPupper (2.6 ± 1.3 versus 1.8 ± 0.7, p = 0.042). Conclusions PEEPupper is a rational selection in ARDS cases with two similar best Crs. EIT provides additional information for the selection of PEEP in such circumstances. Supplementary Information The online version contains supplementary material available at 10.1007/s40846-021-00668-2.
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Affiliation(s)
- Po-Lan Su
- Institute of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan.,Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng-Kung University, Tainan, 70403 Taiwan
| | - Wei-Chieh Lin
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng-Kung University, Tainan, 70403 Taiwan
| | - Yen-Fen Ko
- Institute of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Kuo-Sung Cheng
- Institute of Biomedical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Chang-Wen Chen
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng-Kung University, Tainan, 70403 Taiwan.,Medical Device Innovation Center, National Cheng Kung University, Tainan, Taiwan
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Over-distension prediction via hysteresis loop analysis and patient-specific basis functions in a virtual patient model. Comput Biol Med 2021; 141:105022. [PMID: 34801244 DOI: 10.1016/j.compbiomed.2021.105022] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 11/02/2021] [Accepted: 11/04/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND OBJECTIVE Recruitment maneuvers (RMs) with subsequent positive-end-expiratory-pressure (PEEP) have proven effective in recruiting lung volume and preventing alveolar collapse. However, a suboptimal PEEP could induce undesired injury in lungs by insufficient or excessive breath support. Thus, a predictive model for patient response under PEEP changes could improve clinical care and lower risks. METHODS This research adds novel elements to a virtual patient model to identify and predict patient-specific lung distension to optimise and personalise care. Model validity and accuracy are validated using data from 18 volume-controlled ventilation (VCV) patients at 7 different baseline PEEP levels (0-12cmH2O), yielding 623 prediction cases. Predictions were made up to ΔPEEP = 12cmH2O ahead covering 6x2cmH2O PEEP steps. RESULTS Using the proposed lung distension model, 90% of absolute peak inspiratory pressure (PIP) prediction errors compared to clinical measurement are within 3.95cmH2O, compared with 4.76cmH2O without this distension term. Comparing model-predicted and clinically measured distension had high correlation increasing to R2 = 0.93-0.95 if maximum ΔPEEP ≤ 6cmH2O. Predicted dynamic functional residual capacity (Vfrc) changes as PEEP rises yield 0.013L median prediction error for both prediction groups and overall R2 of 0.84. CONCLUSIONS Overall results demonstrate nonlinear distension mechanics are accurately captured in virtual lung mechanics patients for mechanical ventilation, for the first time. This result can minimise the risk of lung injury by predicting its potential occurrence of distension before changing ventilator settings. The overall outcomes significantly extend and more fully validate this virtual mechanical ventilation patient model.
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Stavi D, Goffi A, Al Shalabi M, Piraino T, Chen L, Jackson R, Brochard L. The Pressure Paradox: Abdominal Compression to Detect Lung Hyper-Inflation in COVID-19 ARDS. Am J Respir Crit Care Med 2021; 205:245-247. [PMID: 34748470 PMCID: PMC8787257 DOI: 10.1164/rccm.202104-1062im] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Dekel Stavi
- University of Toronto, 7938, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada.,University Health Network, 7989, Critical Care Medicine, Toronto, Ontario, Canada.,St. Michael's Hospital, Critical Care Medicine, Toronto, Ontario, Canada
| | - Alberto Goffi
- University of Toronto, 7938, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada.,St. Michael's Hospital, Critical Care Medicine, Toronto, Ontario, Canada.,St Michael's Hospital Li Ka Shing Knowledge Institute, 518773, Keenan Research Centre, Toronto, Ontario, Canada.,University of Toronto, 7938, Department of Medicine, Toronto, Ontario, Canada;
| | - Mufid Al Shalabi
- St Michael's Hospital, 10071, Toronto, Ontario, Canada.,Nottingham University Hospitals NHS Trust, 9820, Nottingham, Nottingham, United Kingdom of Great Britain and Northern Ireland
| | - Thomas Piraino
- University of Toronto, 7938, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada.,St. Michael's Hospital, Adult Critical Care Medicine, Toronto, Ontario, Canada.,Kingston Health Sciences Centre, 71459, Kingston, Ontario, Canada
| | - Lu Chen
- St Michael's Hospital, 10071, Toronto, Ontario, Canada
| | - Robert Jackson
- University of Toronto, 7938, Department of Medicine, Toronto, Ontario, Canada
| | - Laurent Brochard
- St Michael's Hospital in Toronto, Li Ka Shing Knowledge Institute, Keenan Research Centre, Toronto, Ontario, Canada.,University of Toronto, 7938, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada
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Regli A, Ahmadi-Noorbakhsh S, Musk GC, Reese DJ, Herrmann P, Firth MJ, Pillow JJ. Computed tomographic assessment of lung aeration at different positive end-expiratory pressures in a porcine model of intra-abdominal hypertension and lung injury. Intensive Care Med Exp 2021; 9:52. [PMID: 34608559 PMCID: PMC8489364 DOI: 10.1186/s40635-021-00416-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 09/21/2021] [Indexed: 11/18/2022] Open
Abstract
Background Intra-abdominal hypertension (IAH) is common in critically ill patients and is associated with increased morbidity and mortality. High positive end-expiratory pressures (PEEP) can reverse lung volume and oxygenation decline caused by IAH, but its impact on alveolar overdistension is less clear. We aimed to find a PEEP range that would be high enough to reduce atelectasis, while low enough to minimize alveolar overdistention in the presence of IAH and lung injury. Methods Five anesthetized pigs received standardized anesthesia and mechanical ventilation. Peritoneal insufflation of air was used to generate intra-abdominal pressure of 27 cmH2O. Lung injury was created by intravenous oleic acid. PEEP levels of 5, 12, 17, 22, and 27 cmH2O were applied. We performed computed tomography and measured arterial oxygen levels, respiratory mechanics, and cardiac output 5 min after each new PEEP level. The proportion of overdistended, normally aerated, poorly aerated, and non-aerated atelectatic lung tissue was calculated based on Hounsfield units. Results PEEP decreased the proportion of poorly aerated and atelectatic lung, while increasing normally aerated lung. Overdistension increased with each incremental increase in applied PEEP. “Best PEEP” (respiratory mechanics or oxygenation) was higher than the “optimal CT inflation PEEP range” (difference between lower inflection points of atelectatic and overdistended lung) in healthy and injured lungs. Conclusions Our findings in a large animal model suggest that titrating a PEEP to respiratory mechanics or oxygenation in the presence of IAH is associated with increased alveolar overdistension. Supplementary Information The online version contains supplementary material available at 10.1186/s40635-021-00416-5.
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Affiliation(s)
- Adrian Regli
- Department of Intensive Care, Fiona Stanley Hospital, Murdoch Drive, Murdoch, WA, 6150, Australia. .,Medical School, Division of Emergency Medicine, The University of Western Australia, 35 Stirling Highway, Crawley, 6009, Australia. .,Medical School, The University of Notre Dame Australia, 19 Mouat Street, Fremantle, 6959, Australia. .,School of Human Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, 6009, Australia.
| | - Siavash Ahmadi-Noorbakhsh
- School of Human Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, 6009, Australia
| | - Gabrielle Christine Musk
- Animal Care Services, The University of Western Australia, 35 Stirling Highway, Crawley, 6009, Australia.,School of Veterinary and Life Sciences, Murdoch University, Nyarrie Drive, Murdoch, 6150, Australia
| | - David Joseph Reese
- VetCT Consultants in Telemedicine PTY LTD, 185-187 High Street, Fremantle, 6160, Australia
| | - Peter Herrmann
- Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen, Robert-Koch-Str. 40, 37075, Göttingen, Germany
| | - Martin Joseph Firth
- Centre for Applied Statistics, Department of Mathematics and Statistics, The University of Western Australia, 35 Stirling Highway, Crawley, 6009, Australia
| | - J Jane Pillow
- School of Human Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, 6009, Australia
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Agrawal DK, Smith BJ, Sottile PD, Albers DJ. A Damaged-Informed Lung Ventilator Model for Ventilator Waveforms. Front Physiol 2021; 12:724046. [PMID: 34658911 PMCID: PMC8517122 DOI: 10.3389/fphys.2021.724046] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/01/2021] [Indexed: 12/31/2022] Open
Abstract
Motivated by a desire to understand pulmonary physiology, scientists have developed physiological lung models of varying complexity. However, pathophysiology and interactions between human lungs and ventilators, e.g., ventilator-induced lung injury (VILI), present challenges for modeling efforts. This is because the real-world pressure and volume signals may be too complex for simple models to capture, and while complex models tend not to be estimable with clinical data, limiting clinical utility. To address this gap, in this manuscript we developed a new damaged-informed lung ventilator (DILV) model. This approach relies on mathematizing ventilator pressure and volume waveforms, including lung physiology, mechanical ventilation, and their interaction. The model begins with nominal waveforms and adds limited, clinically relevant, hypothesis-driven features to the waveform corresponding to pulmonary pathophysiology, patient-ventilator interaction, and ventilator settings. The DILV model parameters uniquely and reliably recapitulate these features while having enough flexibility to reproduce commonly observed variability in clinical (human) and laboratory (mouse) waveform data. We evaluate the proof-in-principle capabilities of our modeling approach by estimating 399 breaths collected for differently damaged lungs for tightly controlled measurements in mice and uncontrolled human intensive care unit data in the absence and presence of ventilator dyssynchrony. The cumulative value of mean squares error for the DILV model is, on average, ≈12 times less than the single compartment lung model for all the waveforms considered. Moreover, changes in the estimated parameters correctly correlate with known measures of lung physiology, including lung compliance as a baseline evaluation. Our long-term goal is to use the DILV model for clinical monitoring and research studies by providing high fidelity estimates of lung state and sources of VILI with an end goal of improving management of VILI and acute respiratory distress syndrome.
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Affiliation(s)
- Deepak K. Agrawal
- Department of Bioengineering, University of Colorado Denver|Anschutz Medical Campus, Aurora, CO, United States
- Section of Informatics and Data Science, Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Bradford J. Smith
- Department of Bioengineering, University of Colorado Denver|Anschutz Medical Campus, Aurora, CO, United States
- Section of Pulmonary and Sleep Medicine, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Peter D. Sottile
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
| | - David J. Albers
- Department of Bioengineering, University of Colorado Denver|Anschutz Medical Campus, Aurora, CO, United States
- Section of Informatics and Data Science, Department of Pediatrics, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Biomedical Informatics, Columbia University, New York, NY, United States
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Personalized Positive End-Expiratory Pressure and Tidal Volume in Acute Respiratory Distress Syndrome: Bedside Physiology-Based Approach. Crit Care Explor 2021; 3:e0486. [PMID: 34278316 PMCID: PMC8280087 DOI: 10.1097/cce.0000000000000486] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVES: Positive end-expiratory pressure and tidal volume may have a key role for the outcome of patients with acute respiratory distress syndrome. The variety of acute respiratory distress syndrome phenotypes implies personalization of those settings. To guide personalized positive end-expiratory pressure and tidal volume, physicians need to have an in-depth understanding of the physiologic effects and bedside methods to measure the extent of these effects. In the present article, a step-by-step physiologic approach to select personalized positive end-expiratory pressure and tidal volume at the bedside is described. DATA SOURCES: The present review is a critical reanalysis of the traditional and latest literature on the topic. STUDY SELECTION: Relevant clinical and physiologic studies on positive end-expiratory pressure and tidal volume setting were reviewed. DATA EXTRACTION: Reappraisal of the available physiologic and clinical data. DATA SYNTHESIS: Positive end-expiratory pressure is aimed at stabilizing alveolar recruitment, thus reducing the risk of volutrauma and atelectrauma. Bedside assessment of the potential for lung recruitment is a preliminary step to recognize patients who benefit from higher positive end-expiratory pressure level. In patients with higher potential for lung recruitment, positive end-expiratory pressure could be selected by physiology-based methods balancing recruitment and overdistension. In patients with lower potential for lung recruitment or in shock, positive end-expiratory pressure could be maintained in the 5–8 cm H2O range. Tidal volume induces alveolar recruitment and improves gas exchange. After setting personalized positive end-expiratory pressure, tidal volume could be based on lung inflation (collapsed lung size) respecting safety thresholds of static and dynamic lung stress. Positive end-expiratory pressure and tidal volume could be kept stable for some hours in order to allow early recognition of changes in the clinical course of acute respiratory distress syndrome but also frequently reassessed to avoid crossing of safety thresholds. CONCLUSIONS: The setting of personalized positive end-expiratory pressure and tidal volume based on sound physiologic bedside measures may represent an effective strategy for treating acute respiratory distress syndrome patients.
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Albani F, Pisani L, Ciabatti G, Fusina F, Buizza B, Granato A, Lippolis V, Aniballi E, Murgolo F, Rosano A, Latronico N, Antonelli M, Grasso S, Natalini G. Flow Index: a novel, non-invasive, continuous, quantitative method to evaluate patient inspiratory effort during pressure support ventilation. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2021; 25:196. [PMID: 34099028 PMCID: PMC8182360 DOI: 10.1186/s13054-021-03624-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 05/31/2021] [Indexed: 02/08/2023]
Abstract
Background The evaluation of patient effort is pivotal during pressure support ventilation, but a non-invasive, continuous, quantitative method to assess patient inspiratory effort is still lacking. We hypothesized that the concavity of the inspiratory flow-time waveform could be useful to estimate patient’s inspiratory effort. The purpose of this study was to assess whether the shape of the inspiratory flow, as quantified by a numeric indicator, could be associated with inspiratory effort during pressure support ventilation. Methods Twenty-four patients in pressure support ventilation were enrolled. A mathematical relationship describing the decay pattern of the inspiratory flow profile was developed. The parameter hypothesized to estimate effort was named Flow Index. Esophageal pressure, airway pressure, airflow, and volume waveforms were recorded at three support levels (maximum, minimum and baseline). The association between Flow Index and reference measures of patient effort (pressure time product and pressure generated by respiratory muscles) was evaluated using linear mixed effects models adjusted for tidal volume, respiratory rate and respiratory rate/tidal volume. Results Flow Index was different at the three pressure support levels and all group comparisons were statistically significant. In all tested models, Flow Index was independently associated with patient effort (p < 0.001). Flow Index prediction of inspiratory effort agreed with esophageal pressure-based methods. Conclusions Flow Index is associated with patient inspiratory effort during pressure support ventilation, and may provide potentially useful information for setting inspiratory support and monitoring patient-ventilator interactions. Supplementary Information The online version contains supplementary material available at 10.1186/s13054-021-03624-3.
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Affiliation(s)
- Filippo Albani
- Department of Anesthesia and Intensive Care, Fondazione Poliambulanza, Brescia, Italy
| | - Luigi Pisani
- Department of Anesthesia and Intensive Care, Miulli Regional Hospital, Acquaviva Delle Fonti, Bari, Italy.,Mahidol Oxford Clinical Research Unit (MORU), Bangkok, Thailand
| | - Gianni Ciabatti
- Department of Anesthesiology, Neurointensive Care Unit, Azienda Ospedaliera Universitaria Careggi, Firenze, Italy
| | - Federica Fusina
- Department of Anesthesia and Intensive Care, Fondazione Poliambulanza, Brescia, Italy.
| | - Barbara Buizza
- Department of Anesthesia and Intensive Care, Spedali Civili, Brescia, Italy
| | - Anna Granato
- Department of Anesthesia and Intensive Care, Fondazione Poliambulanza, Brescia, Italy
| | - Valeria Lippolis
- Department of Anesthesia and Intensive Care, Mater Dei Hospital, Bari, Italy
| | - Eros Aniballi
- Department of Anesthesia, I.R.C.C.S. MultiMedica, Sesto San Giovanni, Milano, Italy
| | - Francesco Murgolo
- Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
| | - Antonio Rosano
- Department of Anesthesia and Intensive Care, Fondazione Poliambulanza, Brescia, Italy
| | - Nicola Latronico
- Department of Anesthesia and Intensive Care, Spedali Civili, Brescia, Italy.,Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Brescia, Italy
| | - Massimo Antonelli
- Department of Intensive Care and Anesthesiology, Fondazione Policlinico, Universitario A. Gemelli, Roma, Italy
| | - Salvatore Grasso
- Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy
| | - Giuseppe Natalini
- Department of Anesthesia and Intensive Care, Fondazione Poliambulanza, Brescia, Italy
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Carteaux G, Tuffet S, Mekontso Dessap A. Potential protective effects of continuous anterior chest compression in the acute respiratory distress syndrome: physiology of an illustrative case. Crit Care 2021; 25:187. [PMID: 34074334 PMCID: PMC8169405 DOI: 10.1186/s13054-021-03619-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 05/26/2021] [Indexed: 12/02/2022] Open
Affiliation(s)
- Guillaume Carteaux
- Assistance Publique- Hôpitaux de Paris, Service de Réanimation Médicale, CHU Henri Mondor-Albert Chenevier, 51, Avenue du Maréchal de Lattre de Tassigny, 94010, Créteil Cedex, France. .,Groupe de Recherche Clinique CARMAS, Université Paris Est-Créteil, 94010, Créteil, France. .,Institut Mondor de Recherche Biomédicale INSERM 955, 94010, Créteil, France.
| | - Samuel Tuffet
- Assistance Publique- Hôpitaux de Paris, Service de Réanimation Médicale, CHU Henri Mondor-Albert Chenevier, 51, Avenue du Maréchal de Lattre de Tassigny, 94010, Créteil Cedex, France.,Groupe de Recherche Clinique CARMAS, Université Paris Est-Créteil, 94010, Créteil, France.,Institut Mondor de Recherche Biomédicale INSERM 955, 94010, Créteil, France
| | - Armand Mekontso Dessap
- Assistance Publique- Hôpitaux de Paris, Service de Réanimation Médicale, CHU Henri Mondor-Albert Chenevier, 51, Avenue du Maréchal de Lattre de Tassigny, 94010, Créteil Cedex, France.,Groupe de Recherche Clinique CARMAS, Université Paris Est-Créteil, 94010, Créteil, France
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Lee PH, Kuo CT, Hsu CY, Lin SP, Fu PK. Prognostic Factors to Predict ICU Mortality in Patients with Severe ARDS Who Received Early and Prolonged Prone Positioning Therapy. J Clin Med 2021; 10:jcm10112323. [PMID: 34073532 PMCID: PMC8198972 DOI: 10.3390/jcm10112323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 05/22/2021] [Accepted: 05/24/2021] [Indexed: 12/29/2022] Open
Abstract
Early and prolonged prone positioning (PP) therapy improve survival in advanced ARDS; however, the predictors of mortality remain unclear. The study aims to identify predictive factors correlated with mortality and build-up the prognostic score in patients with severe ARDS who received early and prolonged PP therapy. A total of 116 patients were enrolled in this retrospective cohort study. Univariate and multivariate regression models were used to estimate the odds ratio (OR) of mortality. Factors associated with mortality were assessed by Cox regression analysis and presented as the hazard ratio (HR) and 95% CI. In the multivariate regression model, renal replacement therapy (RRT; OR: 4.05, 1.54–10.67), malignant comorbidity (OR: 8.86, 2.22–35.41), and non-influenza-related ARDS (OR: 5.17, 1.16–23.16) were significantly associated with ICU mortality. Age, RRT, non-influenza-related ARDS, malignant comorbidity, and APACHE II score were included in a composite prone score, which demonstrated an area under the curve of 0.816 for predicting mortality risk. In multivariable Cox proportional hazard model, prone score more than 3 points was significantly associated with ICU mortality (HR: 2.13, 1.12–4.07, p = 0.021). We suggest prone score ≥3 points could be a good predictor for mortality in severe ARDS received PP therapy.
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Affiliation(s)
- Po-Hsin Lee
- Division of Chest, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung 407219, Taiwan;
| | - Chen-Tsung Kuo
- Computer & Communications Center, Taipei Veterans General Hospital, Taipei 11217, Taiwan;
| | - Chiann-Yi Hsu
- Biostatistics Task Force of Taichung Veterans General Hospital, Taichung 407219, Taiwan;
| | - Shih-Pin Lin
- Department of Critical Care Medicine, Taichung Veterans General Hospital, Taichung 407219, Taiwan;
| | - Pin-Kuei Fu
- Department of Critical Care Medicine, Taichung Veterans General Hospital, Taichung 407219, Taiwan;
- Ph.D. Program in Translational Medicine, National Chung Hsing University, Taichung 402010, Taiwan
- College of Human Science and Social Innovation, Hungkuang University, Taichung 433304, Taiwan
- Department of Computer Science, Tunghai University, Taichung 407224, Taiwan
- Correspondence: ; Tel.: +886-937-701-592
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Affiliation(s)
- Neil MacIntyre
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Craig Rackley
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC
| | - Felix Khusid
- Department of Respiratory Therapy, NewYork-Presbyterian Brooklyn Methodist Hospital, Brooklyn, NY
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38
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Nguyen TK, Nguyen VL, Nguyen TG, Mai DH, Nguyen NQ, Vu TA, Le AN, Nguyen QH, Nguyen CT, Nguyen DT. Lung-protective mechanical ventilation for patients undergoing abdominal laparoscopic surgeries: a randomized controlled trial. BMC Anesthesiol 2021; 21:95. [PMID: 33784987 PMCID: PMC8008676 DOI: 10.1186/s12871-021-01318-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 03/17/2021] [Indexed: 11/10/2022] Open
Abstract
Background Pneumoperitoneum and Trendelenburg position in laparoscopic surgeries could contribute to postoperative pulmonary dysfunction. In recent years, intraoperative lung-protective mechanical ventilation (LPV) has been reportedly able to attenuate ventilator-induced lung injuries (VILI). Our objectives were to test the hypothesis that LPV could improve intraoperative oxygenation function, pulmonary mechanics and early postoperative atelectasis in laparoscopic surgeries. Methods In this randomized controlled clinical trial, 62 patients indicated for elective abdominal laparoscopic surgeries with an expected duration of greater than 2 h were randomly assigned to receive either lung-protective ventilation (LPV) with a tidal volume (Vt) of 7 ml kg− 1 ideal body weight (IBW), 10 cmH2O positive end-expiratory pressure (PEEP) combined with regular recruitment maneuvers (RMs) or conventional ventilation (CV) with a Vt of 10 ml kg− 1 IBW, 0 cmH2O in PEEP and no RMs. The primary endpoints were the changes in the ratio of PaO2 to FiO2 (P/F). The secondary endpoints were the differences between the two groups in PaO2, alveolar-arterial oxygen gradient (A-aO2), intraoperative pulmonary mechanics and the incidence of atelectasis detected on chest x-ray on the first postoperative day. Results In comparison to CV group, the intraoperative P/F and PaO2 in LPV group were significantly higher while the intraoperative A-aO2 was clearly lower. Cdyn and Cstat at all the intraoperative time points in LPV group were significantly higher compared to CV group (p < 0.05). There were no differences in the incidence of atelectasis on day one after surgery between the two groups. Conclusions Lung protective mechanical ventilation significantly improved intraoperative pulmonary oxygenation function and pulmonary compliance in patients experiencing various abdominal laparoscopic surgeries, but it could not ameliorate early postoperative atelectasis and oxygenation function on the first day after surgery. Trial registration https://www.clinicaltrials.gov/identifier: NCT04546932 (09/05/2020).
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Affiliation(s)
- Trung Kien Nguyen
- Center of Emergency, Critical Care Medicine and Clinical Toxicology, 103 Military Hospital, Vietnam Military Medical University, 261 Phung Hung road, Ha Dong District, Hanoi City, Vietnam
| | - Viet Luong Nguyen
- Critical Care Unit, National Burn Hospital, Vietnam Military Medical University, Hanoi, Vietnam
| | - Truong Giang Nguyen
- Department of Cardiothoracic surgery, 103 Military Hospital, Vietnam Military Medical University, Hanoi, Vietnam
| | - Duc Hanh Mai
- Department of Anesthesia and Pain Medicine, 103 Military Hospital, Vietnam Military Medical University, Hanoi, Vietnam
| | - Ngoc Quynh Nguyen
- Department of Anesthesia and Pain Medicine, Vietnam National Cancer Hospital, Hanoi, Vietnam
| | - The Anh Vu
- Department of Anesthesia and Pain Medicine, 103 Military Hospital, Vietnam Military Medical University, Hanoi, Vietnam.
| | - Anh Nguyet Le
- Department of Urology, 103 Military Hospital, Vietnam Military Medical University, Hanoi, Vietnam
| | - Quang Huy Nguyen
- Center of Emergency, Critical Care Medicine and Clinical Toxicology, 103 Military Hospital, Vietnam Military Medical University, 261 Phung Hung road, Ha Dong District, Hanoi City, Vietnam
| | - Chi Tue Nguyen
- Center of Emergency, Critical Care Medicine and Clinical Toxicology, 103 Military Hospital, Vietnam Military Medical University, 261 Phung Hung road, Ha Dong District, Hanoi City, Vietnam
| | - Dang Thu Nguyen
- Department of Anesthesia and Pain Medicine, 103 Military Hospital, Vietnam Military Medical University, Hanoi, Vietnam
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Costamagna A, Pivetta E, Goffi A, Steinberg I, Arina P, Mazzeo AT, Del Sorbo L, Veglia S, Davini O, Brazzi L, Ranieri VM, Fanelli V. Clinical performance of lung ultrasound in predicting ARDS morphology. Ann Intensive Care 2021; 11:51. [PMID: 33779834 PMCID: PMC8006629 DOI: 10.1186/s13613-021-00837-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 03/09/2021] [Indexed: 12/28/2022] Open
Abstract
Background To assess diagnostic performance of lung ultrasound (LUS) in identifying ARDS morphology (focal vs non-focal), compared with the gold standard computed tomography. Methods Mechanically ventilated ARDS patients undergoing lung computed tomography and ultrasound were enrolled. Twelve fields, were evaluated. LUS score was graded from 0 (normal) to 3 (consolidation) according to B-lines extent. Total and regional LUS score as the sum of the four ventral (LUSV), intermediate (LUSI) or dorsal (LUSD) fields, were calculated. Based on lung CT, ARDS morphology was defined as (1) focal (loss of aeration with lobar distribution); (2) non-focal (widespread loss of aeration or segmental loss of aeration distribution associated with uneven lung attenuation areas), and diagnostic accuracy of LUS in discriminating ARDS morphology was determined by AU-ROC in training and validation set of patients. Results Forty-seven patients with ARDS (25 training set and 22 validation set) were enrolled. LUSTOT, LUSV and LUSI but not LUSD score were significantly lower in focal than in non-focal ARDS morphologies (p < .01). The AU-ROC curve of LUSTOT, LUSV, LUSI and LUSD for identification of non-focal ARDS morphology were 0.890, 0.958, 0.884 and 0.421, respectively. LUSV value ≥ 3 had the best predictive value (sensitivity = 0.95, specificity = 1.00) in identifying non-focal ARDS morphology. In the validation set, an LUSV score ≥ 3 confirmed to be highly predictive of non-focal ARDS morphology, with a sensitivity and a specificity of 94% and 100%. Conclusions LUS had a valuable performance in distinguishing ARDS morphology. Supplementary Information The online version contains supplementary material available at 10.1186/s13613-021-00837-1.
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Affiliation(s)
- Andrea Costamagna
- Department of Anaesthesia and Critical Care, AOU Città della Salute e della Scienza di Torino, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy
| | - Emanuele Pivetta
- Department of General and Specialized Medicine, Division of Emergency Medicine and High Dependency Unit, Cancer Epidemiology Unit - AOU Città Della Salute e Della Scienza di Torino, Turin, Italy
| | - Alberto Goffi
- Interdepartmental Division of Critical Care Medicine and Department of Medicine, University of Toronto, Toronto, ON, Canada.,Department of Medicine, Division of Critical Care Medicine, St. Michael's Hospital, Toronto, ON, Canada
| | - Irene Steinberg
- Department of Surgical Sciences, University of Turin, Turin, Italy
| | - Pietro Arina
- Department of Surgical Sciences, University of Turin, Turin, Italy
| | - Anna Teresa Mazzeo
- Department of Surgical Sciences, University of Turin, Turin, Italy.,Dipartimento di Patologia Umana Dell'adulto e Dell'età Evolutiva, Anestesia e Rianimazione, Univesity of Messina, Messina, Italy
| | - Lorenzo Del Sorbo
- Interdepartmental Division of Critical Care Medicine and Department of Medicine, University of Toronto, Toronto, ON, Canada.,Department of Medicine, Division of Respirology (Critical Care), University Health Network, Toronto, ON, Canada
| | - Simona Veglia
- Department of Diagnostic Imaging and Radiotherapy, AOU Città della Salute e della Scienza di Torino-University of Turin, Turin, Italy
| | - Ottavio Davini
- Department of Diagnostic Imaging and Radiotherapy, AOU Città della Salute e della Scienza di Torino-University of Turin, Turin, Italy
| | - Luca Brazzi
- Department of Anaesthesia and Critical Care, AOU Città della Salute e della Scienza di Torino, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy.,Department of Surgical Sciences, University of Turin, Turin, Italy
| | - V Marco Ranieri
- Alma Mater Studiorum, Dipartimento di Scienze Mediche e Chirurgiche, Anesthesia and Intensive Care Medicine, Policlinico di Sant'Orsola, Università di Bologna, Bologna, Italy
| | - Vito Fanelli
- Department of Anaesthesia and Critical Care, AOU Città della Salute e della Scienza di Torino, University of Turin, Corso Dogliotti 14, 10126, Turin, Italy. .,Department of Surgical Sciences, University of Turin, Turin, Italy.
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Protective mechanical ventilation in the obese patient. Int Anesthesiol Clin 2021; 58:53-57. [PMID: 32404605 DOI: 10.1097/aia.0000000000000284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Effects of Positive End-Expiratory Pressure in "High Compliance" Severe Acute Respiratory Syndrome Coronavirus 2 Acute Respiratory Distress Syndrome. Crit Care Med 2020; 48:e1332-e1336. [PMID: 32932346 DOI: 10.1097/ccm.0000000000004640] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Clinical observation suggests that early acute respiratory distress syndrome induced by the severe acute respiratory syndrome coronavirus 2 may be "atypical" due to a discrepancy between a relatively unaffected static respiratory system compliance and a significant hypoxemia. This would imply an "atypical" response to the positive end-expiratory pressure. DESIGN Single-center, unblinded, crossover study. SETTING ICU of Bari Policlinico Academic Hospital (Italy), dedicated to care patients with confirmed diagnosis of novel coronavirus disease 2019. PATIENTS Eight patients with early severe acute respiratory syndrome coronavirus 2 acute respiratory distress syndrome and static respiratory compliance higher than or equal to 50 mL/cm H2O. INTERVENTIONS We compared a "lower" and a "higher" positive end-expiratory pressure approach, respectively, according to the intervention arms of the acute respiratory distress syndrome network and the positive end-expiratory pressure setting in adults with acute respiratory distress syndrome studies. MEASUREMENTS AND MAIN RESULTS Patients were ventilated with the acute respiratory distress syndrome network and, subsequently, with the ExPress protocol. After 1 hour of ventilation, for each protocol, we recorded arterial blood gas, respiratory mechanics, alveolar recruitment, and hemodynamic variables. Comparisons were performed with analysis of variance for repeated measures or Friedman test as appropriate. Positive end-expiratory pressure was increased from 9 ± 3.5 to 17.7 ± 1.7 cm H2O (p < 0.01). Alveolar recruitment was 450 ± 111 mL. Static respiratory system compliance decreased from 58.3 ± 7.6 mL/cm H2O to 47.4 ± 14.5 mL/cm H2O (p = 0.018) and the "stress index" increased from 0.97 ± 0.03 to 1.22 ± 0.07 (p < 0.001). The PaO2/FIO2 ratio increased from 131 ± 22 to 207 ± 41 (p < 0.001), and the PaCO2 increased from 45.9 ± 12.7 to 49.8 ± 13.2 mm Hg (p < 0.001). The cardiac index went from 3.6 ± 0.4 to 2.9 ± 0.6 L/min/m (p = 0.01). CONCLUSIONS Our data suggest that the "higher" positive end-expiratory pressure approach in patients with severe acute respiratory syndrome coronavirus 2 acute respiratory distress syndrome and high compliance improves oxygenation and lung aeration but may result in alveolar hyperinflation and hemodynamic alterations.
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Battaglini D, Ball L, Wittenstein J, Cohen E, Gama DE Abreu M, Pelosi P. PEEP in thoracic anesthesia: pros and cons. Minerva Anestesiol 2020; 87:223-229. [PMID: 33300325 DOI: 10.23736/s0375-9393.20.14797-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Protective ventilation includes a strategy with low tidal volume, Plateau pressure, driving pressure, positive end-expiratory pressure (PEEP), and recruitment maneuvers on the ventilated lung. The rationale for the application of PEEP during one-lung ventilation (OLV) is that PEEP may contribute to minimize atelectrauma, preventing airway closure and alveolar collapse and improving the ventilation/perfusion to the ventilated lung. However, in case of high partial pressure of oxygen the application of PEEP may cause increased pulmonary vascular resistance, thus diverting blood flow to the non-ventilated lung, and worsening ventilation/perfusion. Further, PEEP may be associated with higher risk of hemodynamic impairment, increased need for fluids and vasoactive drugs. Positive effects on outcome have been reported by titrating PEEP according to driving pressure, targeted to obtain the optimum respiratory as well as pulmonary system compliance. This may vary according to the method employed for titration and should be performed individually for each patient. In summary, the potential for harm combined with the lack of evidence for improved outcome suggest that PEEP must be judiciously used during OLV even when titrated to a safe target, and only as much as necessary to maintain an appropriate gas exchange under low protective tidal volumes and driving pressures.
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Affiliation(s)
- Denise Battaglini
- Department of Anesthesiology and Intensive Care, San Martino Policlinico Hospital, IRCCS Oncology and Neuroscience, Genoa, Italy
| | - Lorenzo Ball
- Department of Anesthesiology and Intensive Care, San Martino Policlinico Hospital, IRCCS Oncology and Neuroscience, Genoa, Italy.,Department of Surgical Science and Integrated Diagnostics (DISC), University of Genoa, Genoa, Italy
| | - Jakob Wittenstein
- Department of Anesthesiology and Intensive Care Therapy, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Edmond Cohen
- Department of Anesthesiology and Thoracic Surgery, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Marcelo Gama DE Abreu
- Department of Anesthesiology and Intensive Care Therapy, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,Outcomes Research Consortium, Cleveland, OH, USA
| | - Paolo Pelosi
- Department of Anesthesiology and Intensive Care, San Martino Policlinico Hospital, IRCCS Oncology and Neuroscience, Genoa, Italy - .,Department of Surgical Science and Integrated Diagnostics (DISC), University of Genoa, Genoa, Italy
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Bedside respiratory physiology to detect risk of lung injury in acute respiratory distress syndrome. Curr Opin Crit Care 2020; 25:3-11. [PMID: 30531534 DOI: 10.1097/mcc.0000000000000579] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE OF REVIEW The most effective strategies for treating the patient with acute respiratory distress syndrome center on minimizing ventilation-induced lung injury (VILI). Yet, current standard-of-care does little to modify mechanical ventilation to patient-specific risk. This review focuses on evaluation of bedside respiratory mechanics, which when interpreted in patient-specific context, affords opportunity to individualize lung-protective ventilation in patients with acute respiratory distress syndrome. RECENT FINDINGS Four biophysical mechanisms of VILI are widely accepted: volutrauma, barotrauma, atelectrauma, and stress concentration. Resulting biotrauma, that is, local and systemic inflammation and endothelial activation, may be thought of as the final common pathway that propagates VILI-mediated multiorgan failure. Conventional, widely utilized techniques to assess VILI risk rely on airway pressure, flow, and volume changes, and remain essential tools for determining overdistension of aerated lung regions, particularly when interpreted cognizant of their limitations. Emerging bedside tools identify regional differences in mechanics, but further study is required to identify how they might best be incorporated into clinical practice. SUMMARY Quantifying patient-specific risk of VILI requires understanding each patient's pulmonary mechanics in context of biological predisposition. Tailoring support at bedside according to these factors affords the greatest opportunity to date for mitigating VILI and alleviating associated morbidity.
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Sahetya SK. Searching for the optimal positive end-expiratory pressure for lung protective ventilation. Curr Opin Crit Care 2020; 26:53-58. [DOI: 10.1097/mcc.0000000000000685] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Brandão JC, Lessa MA, Motta-Ribeiro G, Hashimoto S, Paula LF, Torsani V, Le L, Bao X, Eikermann M, Dahl DM, Deng H, Tabatabaei S, Amato MBP, Vidal Melo MF. Global and Regional Respiratory Mechanics During Robotic-Assisted Laparoscopic Surgery: A Randomized Study. Anesth Analg 2019; 129:1564-1573. [PMID: 31743177 DOI: 10.1213/ane.0000000000004289] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Pneumoperitoneum and nonphysiological positioning required for robotic surgery increase cardiopulmonary risk because of the use of larger airway pressures (Paws) to maintain tidal volume (VT). However, the quantitative partitioning of respiratory mechanics and transpulmonary pressure (PL) during robotic surgery is not well described. We tested the following hypothesis: (1) the components of driving pressure (transpulmonary and chest wall components) increase in a parallel fashion at robotic surgical stages (Trendelenburg and robot docking); and (2) deep, when compared to routine (moderate), neuromuscular blockade modifies those changes in PLs as well as in regional respiratory mechanics. METHODS We studied 35 American Society of Anesthesiologists (ASA) I-II patients undergoing elective robotic surgery. Airway and esophageal balloon pressures and respiratory flows were measured to calculate respiratory mechanics. Regional lung aeration and ventilation was assessed with electrical impedance tomography and level of neuromuscular blockade with acceleromyography. During robotic surgical stages, 2 crossover randomized groups (conditions) of neuromuscular relaxation were studied: Moderate (1 twitch in the train-of-four stimulation) and Deep (1-2 twitches in the posttetanic count). RESULTS Pneumoperitoneum was associated with increases in driving pressure, tidal changes in PL, and esophageal pressure (Pes). Steep Trendelenburg position during robot docking was associated with further worsening of the respiratory mechanics. The fraction of driving pressures that partitioned to the lungs decreased from baseline (63% ± 15%) to Trendelenburg position (49% ± 14%, P < .001), due to a larger increase in chest wall elastance (Ecw; 12.7 ± 7.6 cm H2O·L) than in lung elastance (EL; 4.3 ± 5.0 cm H2O·L, P < .001). Consequently, from baseline to Trendelenburg, the component of Paw affecting the chest wall increased by 6.6 ± 3.1 cm H2O, while PLs increased by only 3.4 ± 3.1 cm H2O (P < .001). PL and driving pressures were larger at surgery end than at baseline and were accompanied by dorsal aeration loss. Deep neuromuscular blockade did not change respiratory mechanics, regional aeration and ventilation, and hemodynamics. CONCLUSIONS In robotic surgery with pneumoperitoneum, changes in ventilatory driving pressures during Trendelenburg and robot docking are distributed less to the lungs than to the chest wall as compared to routine mechanical ventilation for supine patients. This effect of robotic surgery derives from substantially larger increases in Ecw than ELs and reduces the risk of excessive PLs. Deep neuromuscular blockade does not meaningfully change global or regional lung mechanics.
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Affiliation(s)
- Julio C Brandão
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
- Department of Anesthesia, Critical Care and Pain Medicine, UNIFESP, São Paulo, Brazil
| | - Marcos A Lessa
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
- Laboratory of Cardiovascular Investigation, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Gabriel Motta-Ribeiro
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Soshi Hashimoto
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Luis Felipe Paula
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Vinicius Torsani
- Cardio-Pulmonary Department, Pulmonary Division, Heart Institute (Incor), University of São Paulo, Sao Paulo, Brazil
| | - Linh Le
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Xiaodong Bao
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Matthias Eikermann
- Department of Urology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Douglas M Dahl
- Department of Urology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Hao Deng
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Shahin Tabatabaei
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Marcelo B P Amato
- Cardio-Pulmonary Department, Pulmonary Division, Heart Institute (Incor), University of São Paulo, Sao Paulo, Brazil
| | - Marcos F Vidal Melo
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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Grasso S, Spadaro S. Electrical impedance tomography: just another tool or a real advance towards precision-medicine in mechanical ventilation? Minerva Anestesiol 2019; 85:1157-1158. [DOI: 10.23736/s0375-9393.19.13955-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Sklar MC, Patel BK, Beitler JR, Piraino T, Goligher EC. Optimal Ventilator Strategies in Acute Respiratory Distress Syndrome. Semin Respir Crit Care Med 2019; 40:81-93. [PMID: 31060090 PMCID: PMC7117088 DOI: 10.1055/s-0039-1683896] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mechanical ventilation practices in patients with acute respiratory distress syndrome (ARDS) have progressed with a growing understanding of the disease pathophysiology. Paramount to the care of affected patients is the delivery of lung-protective mechanical ventilation which prioritizes tidal volume and plateau pressure limitation. Lung protection can probably be further enhanced by scaling target tidal volumes to the specific respiratory mechanics of individual patients. The best procedure for selecting optimal positive end-expiratory pressure (PEEP) in ARDS remains uncertain; several relevant issues must be considered when selecting PEEP, particularly lung recruitability. Noninvasive ventilation must be used with caution in ARDS as excessively high respiratory drive can further exacerbate lung injury; newer modes of delivery offer promising approaches in hypoxemic respiratory failure. Airway pressure release ventilation offers an alternative approach to maximize lung recruitment and oxygenation, but clinical trials have not demonstrated a survival benefit of this mode over conventional ventilation strategies. Rescue therapy with high-frequency oscillatory ventilation is an important option in refractory hypoxemia. Despite a disappointing lack of benefit (and possible harm) in patients with moderate or severe ARDS, possibly due to lung hyperdistention and right ventricular dysfunction, high-frequency oscillation may improve outcome in patients with very severe hypoxemia.
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Affiliation(s)
- Michael C Sklar
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Bhakti K Patel
- Section of Pulmonary and Critical Care, Department of Medicine, University of Chicago, Chicago, Illinois
| | - Jeremy R Beitler
- Center for Acute Respiratory Failure and Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University, New York, New York
| | - Thomas Piraino
- Keenan Centre for Biomedical Research, St. Michael's Hospital, Toronto, Ontario, Canada.,Division of Critical Care, Department of Anesthesia, McMaster University, Hamilton, Ontario, Canada.,Department of Respiratory Therapy, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Ewan C Goligher
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada.,Toronto General Hospital Research Institute, Toronto, Ontario, Canada.,Department of Medicine, Division of Respirology, University Health Network, Toronto, Ontario, Canada
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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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Russotto V, Bellani G, Foti G. Respiratory mechanics in patients with acute respiratory distress syndrome. ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:382. [PMID: 30460256 DOI: 10.21037/atm.2018.08.32] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Despite the recognition of its iatrogenic potential, mechanical ventilation remains the mainstay of respiratory support for patients with acute respiratory distress syndrome (ARDS). The low volume ventilation has been recognized as the only method to reduce mortality of ARDS patients and plateau pressure as the lighthouse for delivering safe ventilation. Recent investigations suggest that a ventilation based on lung mechanics (tidal ventilation tailored to the available lung volume able to receive it, i.e., driving pressure) is a successful approach to improve outcome. However, currently available bedside mechanical variables do not consider regional mechanical properties of ARDS affected lungs, which include the role of local stress risers at the boundaries of areas with different aeration. A unifying approach considers lung-related causes and ventilation-related causes of lung injury. These last may be incorporated in the mechanical power (i.e., amount of mechanical energy transferred per unit of time). Ventilation-induced lung injury (which includes the self-inflicted lung injury of a spontaneously breathing patient) can therefore be prevented by the adoption of measures promoting an increase of ventilable lung and its homogeneity and by delivering lower levels of mechanical power. Prone position promotes lung homogeneity without increasing the delivered mechanical power. This review describes the recent developments on respiratory mechanics in ARDS patients, providing both bedside and research insights from the most updated evidence.
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Affiliation(s)
- Vincenzo Russotto
- Department of Emergency and Intensive Care, University Hospital San Gerardo, Monza, Italy
| | - Giacomo Bellani
- Department of Emergency and Intensive Care, University Hospital San Gerardo, Monza, Italy.,University of Milano Bicocca, Milano, Italy
| | - Giuseppe Foti
- Department of Emergency and Intensive Care, University Hospital San Gerardo, Monza, Italy.,University of Milano Bicocca, Milano, Italy
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Satalin J, Habashi NM, Nieman GF. Never give the lung the opportunity to collapse. TRENDS IN ANAESTHESIA AND CRITICAL CARE 2018. [DOI: 10.1016/j.tacc.2018.05.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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