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Plotnikow GA, Bianchini FJF, Moracci R, Santana Mackinlay JA, Melgarejo F, Loustau MP, Acevedo VS, Di Salvo E, Gutierrez FJ, Madorno M, Mariani J. Impact of high-flow oxygen therapy via high velocity nasal insufflation on diaphragmatic thickening fraction in healthy subjects. Med Intensiva 2024:S2173-5727(24)00198-X. [PMID: 39048473 DOI: 10.1016/j.medine.2024.05.017] [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: 03/19/2024] [Accepted: 05/22/2024] [Indexed: 07/27/2024]
Abstract
OBJECTIVE The primary objective of this study was to evaluate the impact of high-flow nasal cannula oxygen therapy [HFNC] on the diaphragm thickening fraction. DESIGN Prospective, descriptive, cohort study SETTING: The study was conducted in the Physiology and Respiratory Care Laboratory, Intensive Care Unit, Hospital Británico de Buenos Aires. PARTICIPANTS Thirteen healthy subjects >18 years old INTERVENTIONS: High-flow nasal cannula oxygen therapy MAIN VARIABLES OF INTEREST: Demographic data (age and gender), anthropometric data (weight, height, and body mass index), and clinical and respiratory variables (Diaphragm thickening fraction [DTf], esophageal pressure swing, respiratory rate [RR], esophageal pressure-time product per minute [PTPes/min]). RESULTS Median DTf decreased significantly as flow increased (p < 0.05). The baseline DTf measurement was 21.4 %, 18.3 % with 20 L/m, and 16.4 % with 40 L/m. We also observed a significant decrease in RR as flow increased in HFNC (p < 0.05). In the 8 subjects with recordings, the PTPes/min was 81.3 (±30.8) cmH2O/sec/min and 64.4 (±25.3) cmH2O/sec/min at baseline and 40 L/m respectively (p = 0.044). CONCLUSIONS The use of high-flow oxygen therapy through nasal cannula of HFNC in healthy subjects decreases the DTf and RR in association with increased flow. In addition, the use of 40 L/m flow may reduce the muscular work associated with respiration.
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Affiliation(s)
- Gustavo Adrián Plotnikow
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina; Universidad Abierta Interamericana, Facultad de Medicina y Ciencias de la Salud, Buenos Aires, Buenos Aires, Argentina.
| | - Facundo José Federico Bianchini
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Roque Moracci
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Jaime Andrés Santana Mackinlay
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Federico Melgarejo
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Malena Paula Loustau
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Valeria Silvina Acevedo
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Emanuel Di Salvo
- División de Fisioterapia y Cuidados Respiratorios, Servicio de Rehabilitación, Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Facundo Javier Gutierrez
- Unidad de Cuidados Intensivos, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Matias Madorno
- Instituto Tecnológico de Buenos Aires, MBMEd, Buenos Aires, Argentina
| | - Javier Mariani
- Departamento de Investigación Clínica No Rentada, Hospital Británico de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
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Cammarota G, Vaschetto R, Vetrugno L, Maggiore SM. Monitoring lung recruitment. Curr Opin Crit Care 2024; 30:268-274. [PMID: 38690956 DOI: 10.1097/mcc.0000000000001157] [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: 05/03/2024]
Abstract
PURPOSE OF REVIEW This review explores lung recruitment monitoring, covering techniques, challenges, and future perspectives. RECENT FINDINGS Various methodologies, including respiratory system mechanics evaluation, arterial bold gases (ABGs) analysis, lung imaging, and esophageal pressure (Pes) measurement are employed to assess lung recruitment. In support to ABGs analysis, the assessment of respiratory mechanics with hysteresis and recruitment-to-inflation ratio has the potential to evaluate lung recruitment and enhance mechanical ventilation setting. Lung imaging tools, such as computed tomography scanning, lung ultrasound, and electrical impedance tomography (EIT) confirm their utility in following lung recruitment with the advantage of radiation-free and repeatable application at the bedside for sonography and EIT. Pes enables the assessment of dorsal lung tendency to collapse through end-expiratory transpulmonary pressure. Despite their value, these methodologies may require an elevated expertise in their application and data interpretation. However, the information obtained by these methods may be conveyed to build machine learning and artificial intelligence algorithms aimed at improving the clinical decision-making process. SUMMARY Monitoring lung recruitment is a crucial component of managing patients with severe lung conditions, within the framework of a personalized ventilatory strategy. Although challenges persist, emerging technologies offer promise for a personalized approach to care in the future.
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Affiliation(s)
- Gianmaria Cammarota
- Department of Translational Medicine, Università del Piemonte Orientale, Novara
| | - Rosanna Vaschetto
- Department of Translational Medicine, Università del Piemonte Orientale, Novara
| | - Luigi Vetrugno
- Department of Medical, Oral and Biotechnological Sciences
| | - Salvatore M Maggiore
- Department of Anesthesiology and Intensive Care, Ospedale SS Annunziata & Department of Innovative Technologies in Medicine and Odonto-stomatology, Università Gabriele D'Annunzio di Chieti-Pescara, Chieti, Italy
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Abbate G, Colombo SM, Semenzin C, Sato N, Liu K, Ainola C, Milani A, Fior G, Obonyo N, White N, Chiumello D, Pauls J, Suen JY, Fraser JF, Li Bassi G. Comparative analysis of novel esophageal pressure monitoring catheters versus commercially available alternatives in a biomechanical model of the thoracic cavity. Sci Rep 2024; 14:9771. [PMID: 38684823 PMCID: PMC11059186 DOI: 10.1038/s41598-024-59790-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 04/15/2024] [Indexed: 05/02/2024] Open
Abstract
Transpulmonary pressure can be estimated using esophageal balloon (EB) catheters, which come in a variety of manufacturing configurations. We assessed the performance of novel polyurethane EB designs, Aspisafe NG and NG+, against existing alternatives. We created a biomechanical model of the chest cavity using a plastic chamber and an ex-vivo porcine esophagus. The chamber was pressurized (- 20 and + 20 cmH2O) to simulate pleural pressures. We conducted tests with various EB inflation volumes and measured transesophageal pressure (TEP). TEP measurement was defined as accurate when the difference between pressure within the EB and chamber was 0 ± 1 cmH2O. We computed the minimal (Vaccuracy-min) and maximal (Vaccuracy-max) EB inflation volumes of accuracy. Inflation volumes were further validated using a surrogate method derived by the clinically validated positive pressure occlusion test (PPOT). When the esophageal balloons were filled with inflation volumes within the range provided by the manufacturers, the accuracy of TEP measurements was marginal. Our tests found median Vaccuracy-min across EB of 0.00-0.50 mL (p = 0.130), whereas Vaccuracy-max ranged 0.50-2.25 mL (p = 0.002). Post PPOT validation, median TEP was - 0.4 cmH2O (- 1.5 to 0.3) (p < 0.001 among catheters). The Aspisafe NG and NG+ were accurate in 81.7% and 77.8% of the measurements, respectively. We characterized two new EBs, which demonstrated good benchtop accuracy in TEP measurements. However, accuracy was notably influenced by the precise selection of EB inflation volumes.
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Affiliation(s)
- Gabriella Abbate
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
- Department of Anesthesia Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Sebastiano Maria Colombo
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
- Department of Anesthesia Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Clayton Semenzin
- School of Engineering and Built Environment, Griffith University, Southport, Australia
| | - Noriko Sato
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
| | - Keibun Liu
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
| | - Carmen Ainola
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
| | - Angelo Milani
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Gabriele Fior
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
- Department of Anesthesia Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Nchafatso Obonyo
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
- Initiative to Develop African Research Leaders/KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Nicole White
- Australian Centre for Health Services Innovation and Centre for Healthcare Transformation, School of Public Health and Social Work, Queensland University of Technology, Brisbane, QLD, Australia
| | | | - Jo Pauls
- School of Engineering and Built Environment, Griffith University, Brisbane, QLD, Australia
| | - Jacky Y Suen
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
- School of Pharmacy and Medical Sciences, Griffith University, Southport, Australia
| | - John F Fraser
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
- Intensive Care Unit, St Andrew's War Memorial Hospital, Spring Hill, QLD, Australia
| | - Gianluigi Li Bassi
- Critical Care Research Group, The Prince Charles Hospital, Brisbane, Australia.
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia.
- Intensive Care Unit, St Andrew's War Memorial Hospital, Spring Hill, QLD, Australia.
- Intensive Care Unit, The Wesley Hospital, Auchenflower, QLD, Australia.
- Wesley Research Institute, Auchenflower, QLD, Australia.
- Critical Care Research Group, The Prince Charles Hospital, 627 Rode Rd, Chermside, QLD, 4032, Australia.
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Menga LS, Subirà C, Wong A, Sousa M, Brochard LJ. Setting positive end-expiratory pressure: does the 'best compliance' concept really work? Curr Opin Crit Care 2024; 30:20-27. [PMID: 38085857 DOI: 10.1097/mcc.0000000000001121] [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 Determining the optimal positive end-expiratory pressure (PEEP) setting remains a central yet debated issue in the management of acute respiratory distress syndrome (ARDS).The 'best compliance' strategy set the PEEP to coincide with the peak respiratory system compliance (or 2 cmH 2 O higher) during a decremental PEEP trial, but evidence is conflicting. RECENT FINDINGS The physiological rationale that best compliance is always representative of functional residual capacity and recruitment has raised serious concerns about its efficacy and safety, due to its association with increased 28-day all-cause mortality in a randomized clinical trial in ARDS patients.Moreover, compliance measurement was shown to underestimate the effects of overdistension, and neglect intra-tidal recruitment, airway closure, and the interaction between lung and chest wall mechanics, especially in obese patients. In response to these concerns, alternative approaches such as recruitment-to-inflation ratio, the nitrogen wash-in/wash-out technique, and electrical impedance tomography (EIT) are gaining attention to assess recruitment and overdistention more reliably and precisely. SUMMARY The traditional 'best compliance' strategy for determining optimal PEEP settings in ARDS carries risks and overlooks some key physiological aspects. The advent of new technologies and methods presents more reliable strategies to assess recruitment and overdistention, facilitating personalized approaches to PEEP optimization.
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Affiliation(s)
- Luca S Menga
- St Michael's Hospital, Li Ka Shing Knowledge Institute, Keenan Research Centre
- University of Toronto, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada
- Università Cattolica del Sacro Cuore, Facoltà di Medicina e Chirurgia, Anesthesiology and Intensive Care Medicine
- Fondazione Policlinico Universitario A. Gemelli IRCCS, Anesthesia, Emergency and Intensive Care Medicine, Roma, Italy
| | - Carles Subirà
- St Michael's Hospital, Li Ka Shing Knowledge Institute, Keenan Research Centre
- University of Toronto, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid
- Critical Care Department, Althaia Xarxa Assistencial Universitària de Manresa, IRIS Research Institute, Manresa, Spain
- Grup de Recerca de Malalt Crític (GMC). Institut de Recerca Biomèdica Catalunya Central IRIS-CC
| | - Alfred Wong
- St Michael's Hospital, Li Ka Shing Knowledge Institute, Keenan Research Centre
- University of Toronto, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada
| | - Mayson Sousa
- St Michael's Hospital, Li Ka Shing Knowledge Institute, Keenan Research Centre
- University of Toronto, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada
| | - Laurent J Brochard
- St Michael's Hospital, Li Ka Shing Knowledge Institute, Keenan Research Centre
- University of Toronto, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada
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Stamatopoulou V, Akoumianaki E, Vaporidi K, Stamatopoulos E, Kondili E, Georgopoulos D. Driving pressure of respiratory system and lung stress in mechanically ventilated patients with active breathing. Crit Care 2024; 28:19. [PMID: 38217038 PMCID: PMC10785492 DOI: 10.1186/s13054-024-04797-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 01/03/2024] [Indexed: 01/14/2024] Open
Abstract
BACKGROUND During control mechanical ventilation (CMV), the driving pressure of the respiratory system (ΔPrs) serves as a surrogate of transpulmonary driving pressure (ΔPlung). Expiratory muscle activity that decreases end-expiratory lung volume may impair the validity of ΔPrs to reflect ΔPlung. This prospective observational study in patients with acute respiratory distress syndrome (ARDS) ventilated with proportional assist ventilation (PAV+), aimed to investigate: (1) the prevalence of elevated ΔPlung, (2) the ΔPrs-ΔPlung relationship, and (3) whether dynamic transpulmonary pressure (Plungsw) and effort indices (transdiaphragmatic and respiratory muscle pressure swings) remain within safe limits. METHODS Thirty-one patients instrumented with esophageal and gastric catheters (n = 22) were switched from CMV to PAV+ and respiratory variables were recorded, over a maximum of 24 h. To decrease the contribution of random breaths with irregular characteristics, a 7-breath moving average technique was applied. In each patient, measurements were also analyzed per deciles of increasing lung elastance (Elung). Patients were divided into Group A, if end-inspiratory transpulmonary pressure (PLEI) increased as Elung increased, and Group B, which showed a decrease or no change in PLEI with Elung increase. RESULTS In 44,836 occluded breaths, ΔPlung ≥ 12 cmH2O was infrequently observed [0.0% (0.0-16.9%) of measurements]. End-expiratory lung volume decrease, due to active expiration, was associated with underestimation of ΔPlung by ΔPrs, as suggested by a negative linear relationship between transpulmonary pressure at end-expiration (PLEE) and ΔPlung/ΔPrs. Group A included 17 and Group B 14 patients. As Elung increased, ΔPlung increased mainly due to PLEI increase in Group A, and PLEE decrease in Group B. Although ΔPrs had an area receiver operating characteristic curve (AUC) of 0.87 (95% confidence intervals 0.82-0.92, P < 0.001) for ΔPlung ≥ 12 cmH2O, this was due exclusively to Group A [0.91 (0.86-0.95), P < 0.001]. In Group B, ΔPrs showed no predictive capacity for detecting ΔPlung ≥ 12 cmH2O [0.65 (0.52-0.78), P > 0.05]. Most of the time Plungsw and effort indices remained within safe range. CONCLUSION In patients with ARDS ventilated with PAV+, injurious tidal lung stress and effort were infrequent. In the presence of expiratory muscle activity, ΔPrs underestimated ΔPlung. This phenomenon limits the usefulness of ΔPrs as a surrogate of tidal lung stress, regardless of the mode of support.
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Affiliation(s)
- Vaia Stamatopoulou
- Intensive Care Medicine Department, University Hospital of Heraklion, Heraklion, Crete, Greece
| | - Evangelia Akoumianaki
- Intensive Care Medicine Department, University Hospital of Heraklion, Heraklion, Crete, Greece
- Medical School, University of Crete, Heraklion, Crete, Greece
| | - Katerina Vaporidi
- Intensive Care Medicine Department, University Hospital of Heraklion, Heraklion, Crete, Greece
- Medical School, University of Crete, Heraklion, Crete, Greece
| | - Efstathios Stamatopoulos
- Decision Support Systems, Laboratory, School of Electrical and Computer Engineering, National Technical University of Athens, Athens, Greece
| | - Eumorfia Kondili
- Intensive Care Medicine Department, University Hospital of Heraklion, Heraklion, Crete, Greece
- Medical School, University of Crete, Heraklion, Crete, Greece
| | - Dimitrios Georgopoulos
- Intensive Care Medicine Department, University Hospital of Heraklion, Heraklion, Crete, Greece.
- Medical School, University of Crete, Heraklion, Crete, Greece.
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Mireles-Cabodevila E, Fischer M, Wiles S, Chatburn RL. Esophageal Pressure Measurement: A Primer. Respir Care 2023; 68:1281-1294. [PMID: 37433629 PMCID: PMC10468172 DOI: 10.4187/respcare.11157] [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: 07/13/2023]
Abstract
Over the last decade, the literature exploring clinical applications for esophageal manometry in critically ill patients has increased. New mechanical ventilators and bedside monitors allow measurement of esophageal pressures easily at the bedside. The bedside clinician can now evaluate the magnitude and timing of esophageal pressure swings to evaluate respiratory muscle activity and transpulmonary pressures. The respiratory therapist has all the tools to perform these measurements to optimize mechanical ventilation delivery. However, as with any measurement, technique, fidelity, and accuracy are paramount. This primer highlights key knowledge necessary to perform measurements and highlights areas of both uncertainty and ongoing development.
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Affiliation(s)
| | | | - Samuel Wiles
- Respiratory Institute, Cleveland Clinic, Cleveland, Ohio
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Abstract
Advanced respiratory monitoring involves several mini- or noninvasive tools, applicable at bedside, focused on assessing lung aeration and morphology, lung recruitment and overdistention, ventilation-perfusion distribution, inspiratory effort, respiratory drive, respiratory muscle contraction, and patient-ventilator asynchrony, in dealing with acute respiratory failure. Compared to a conventional approach, advanced respiratory monitoring has the potential to provide more insights into the pathologic modifications of lung aeration induced by the underlying disease, follow the response to therapies, and support clinicians in setting up a respiratory support strategy aimed at protecting the lung and respiratory muscles. Thus, in the clinical management of the acute respiratory failure, advanced respiratory monitoring could play a key role when a therapeutic strategy, relying on individualization of the treatments, is adopted.
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Lundstrom JA, Khemani RG, Hotz J, Newth CJL, Achanta S, Gentile MA, Hedin DS. Development of a Pleural Pressure Catheter via Continuous Fiberoptic Esophageal Pressure Measurements. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2022; 2022:3269-3272. [PMID: 36086635 DOI: 10.1109/embc48229.2022.9871790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
There is growing research showing the importance of measuring esophageal pressure as a surrogate for pleural pressure for patients on mechanical ventilators. The most common measurement method uses a balloon catheter, whose accuracy can vary based on patient anatomy, balloon position, balloon inflation, and the presence of other tubes in the esophagus. The authors present the development and initial testing results of a new combination catheter, utilizing fiberoptic pressure sensing to provide more accurate esophageal pressure measurements and allowing for the incorporation of a feeding tube and temperature sensor.
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Thind GS, Mireles-Cabodevila E, Chatburn RL, Duggal A. Evaluation of Esophageal Pressures in Mechanically Ventilated Obese Patients. Respir Care 2022; 67:184-190. [PMID: 34848545 PMCID: PMC9993938 DOI: 10.4187/respcare.08978] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Patients who are obese are at risk for developing high pleural pressure, which leads to alveolar collapse. Esophageal pressure (Pes) can be used as a surrogate for pleural pressure and can be used to guide PEEP titration. Although recent clinical data on Pes-guided PEEP has shown no benefit, its utility in the subgroup of patients who are obese has not been studied. METHODS The Medical Information Mart for Intensive Care-III critical care database was queried to gather data on Pes in subjects on mechanical ventilation. Pes in obese and non-obese groups were compared, and a subgroup analysis was performed in subjects with class III obesity. Thereafter, empirical and Pes-guided PEEP protocols of a recently published trial were theoretically applied to the obese group and ventilator outcomes were compared. RESULTS A total of 105 subjects were included in the study. The average end-expiratory Pes in the obese group was 18.8 ± 5 cm H2O compared with 16.8 ± 4.8 cm H2O in the non-obese group (P < .05). If Pes-guided PEEP protocol was to be applied to those in the obese group, then the PEEP setting would be significantly higher than empirical PEEP setting. These findings were accentuated in the subgroup of subjects with class III obesity. CONCLUSIONS Individualization of PEEP with Pes guidance may have a role in patients who are obese.
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Affiliation(s)
- Guramrinder Singh Thind
- Department of Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, Ohio.
| | | | - Robert L Chatburn
- Department of Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, Ohio
| | - Abhijit Duggal
- Department of Critical Care Medicine, Respiratory Institute, Cleveland Clinic, Cleveland, Ohio
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Partition of respiratory mechanics in patients with acute respiratory distress syndrome and association with outcome: a multicentre clinical study. Intensive Care Med 2022; 48:888-898. [PMID: 35670818 PMCID: PMC9171739 DOI: 10.1007/s00134-022-06724-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 05/02/2022] [Indexed: 02/03/2023]
Abstract
PURPOSE In acute respiratory distress syndrome (ARDS), physiological parameters associated with outcome may help defining targets for mechanical ventilation. This study aimed to address whether transpulmonary pressures (PL), including transpulmonary driving pressure (DPL), elastance-derived plateau PL, and directly-measured end-expiratory PL, are better associated with 60-day outcome than airway driving pressure (DPaw). We also tested the combination of oxygenation and stretch index [PaO2/(FiO2*DPaw)]. METHODS Prospective, observational, multicentre registry of ARDS patients. Respiratory mechanics were measured early after intubation at 6 kg/ml tidal volume. We compared the predictive power of the parameters for mortality at day-60 through receiver operating characteristic (ROC) and assessed their association with 60-day mortality through unadjusted and adjusted Cox regressions. Finally, each parameter was dichotomized, and Kaplan-Meier survival curves were compared. RESULTS 385 patients were enrolled 2 [1-4] days from intubation (esophageal pressure and arterial blood gases in 302 and 318 patients). As continuous variables, DPaw, DPL, and oxygenation stretch index were associated with 60-day mortality after adjustment for age and Sequential Organ Failure Assessment, whereas elastance-derived plateau PL was not. DPaw and DPL performed equally in ROC analysis (P = 0.0835). DPaw had the best-fit Cox regression model. When dichotomizing the variables, DPaw ≥ 15, DPL ≥ 12, plateau PL ≥ 24, and oxygenation stretch index < 10 exhibited lower 60-day survival probability. Directly measured end-expiratory PL ≥ 0 was associated with better outcome in obese patients. CONCLUSION DPL was equivalent predictor of outcome than DPaw. Our study supports the soundness of limiting lung and airway driving pressure and maintaining positive end-expiratory PL in obese patients.
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Abstract
Today's management of the ventilated patient still relies on the measurement of old parameters such as airway pressures and flow. Graphical presentations reveal the intricacies of patient-ventilator interactions in times of supporting the patient on the ventilator instead of fully ventilating the heavily sedated patient. This opens a new pathway for several bedside technologies based on basic physiologic knowledge; however, it may increase the complexity of measurements. The spread of the COVID-19 infection has confronted the anesthesiologist and intensivist with one of the most severe pulmonary pathologies of the last decades. Optimizing the patient at the bedside is an old and newly required skill for all physicians in the intensive care unit, supported by mobile technologies such as lung ultrasound and electrical impedance tomography. This review summarizes old knowledge and presents a brief insight into extended monitoring options.
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Affiliation(s)
- Ralph Gertler
- Department of Anaesthesiology and Intensive Care, HELIOS Klinikum München West, Teaching Hospital of the Ludwig-Maximilians-Universität, Steinerweg 5, München 85241, Germany.
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Sarge T, Baedorf-Kassis E, Banner-Goodspeed V, Novack V, Loring SH, Gong MN, Cook D, Talmor D, Beitler JR. Effect of Esophageal Pressure-Guided Positive End-Expiratory Pressure on Survival from Acute Respiratory Distress Syndrome: A Risk-Based and Mechanistic Reanalysis of the EPVent-2 Trial. Am J Respir Crit Care Med 2021; 204:1153-1163. [PMID: 34464237 DOI: 10.1164/rccm.202009-3539oc] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE In acute respiratory distress syndrome (ARDS), the effect of positive end-expiratory pressure (PEEP) may depend on the extent to which multiorgan dysfunction contributes to risk of death, and the precision with which PEEP is titrated to attenuate atelectrauma without exacerbating overdistension. OBJECTIVE To evaluate whether multiorgan dysfunction and lung mechanics modified treatment effect in EPVent-2, a multicenter trial of esophageal pressure (PES)-guided PEEP versus empirical high PEEP in moderate-to-severe ARDS. METHODS This post-hoc reanalysis of EPVent-2 evaluated for heterogeneity of treatment effect on mortality by baseline multiorgan dysfunction, determined via Acute Physiology and Chronic Health Evaluation-II (APACHE-II). It also evaluated whether PEEP titrated to end-expiratory transpulmonary pressure near 0 cmH2O was associated with survival. MEASUREMENTS AND MAIN RESULTS All 200 trial participants were included. Treatment effect on 60-day mortality differed by multiorgan dysfunction severity (p=0.03 for interaction). PES-guided PEEP was associated with lower mortality among patients with lower APACHE-II (HR 0.43, 95% CI 0.20-0.92 for APACHE-II less than median) and may have had the opposite effect in patients with higher APACHE-II (HR 1.69; 95% CI 0.93-3.05). Independent of treatment group or multiorgan dysfunction severity, mortality was lowest when PEEP titration achieved end-expiratory transpulmonary pressure near 0 cmH2O. CONCLUSIONS The effect on survival of PES-guided PEEP, compared to empirical high PEEP, differed by multiorgan dysfunction severity. Independent of multiorgan dysfunction, PEEP titrated to end-expiratory transpulmonary pressure closer to 0 cmH2O was associated with greater survival than more positive or negative values. These findings warrant prospective testing in a future trial.
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Affiliation(s)
- Todd Sarge
- Beth Israel Deaconess Medical Center, 1859, Anesthesia, Critical Care, and Pain Medicine, Boston, Massachusetts, United States.,Harvard Medical School, 1811, Boston, Massachusetts, United States
| | - Elias Baedorf-Kassis
- Beth Israel Deaconess Medical Center, 1859, Pulmonary and Critical Care Medicine, Boston, Massachusetts, United States.,Harvard Medical School, 1811, Boston, Massachusetts, United States
| | - Valerie Banner-Goodspeed
- Beth Israel Deaconess Medical Center, 1859, Anesthesia, Critical Care, and Pain Medicine, Boston, Massachusetts, United States.,Harvard Medical School, 1811, Boston, Massachusetts, United States
| | - Victor Novack
- Soroka Medical Center, 26746, Clinical Research Center, Beer-Sheva, Israel
| | - Stephen H Loring
- Beth Israel Deaconess Medical Center, 1859, Anesthesia, Critical Care, and Pain Medicine, Boston, Massachusetts, United States.,Harvard Medical School, 1811, Boston, Massachusetts, United States
| | - Michelle N Gong
- Montefiore Medical Center, 2013, Division of Critical Care Medicine, Bronx, New York, United States.,Albert Einstein College of Medicine, 2006, Bronx, New York, United States
| | - Deborah Cook
- McMaster University, 3710, Department of Medicine, Pathology & Molecular Medicine, Hamilton, Ontario, Canada
| | - Daniel Talmor
- Beth Israel Deaconess Medical Center, 1859, Anesthesia, Critical Care, and Pain Medicine, Boston, Massachusetts, United States.,Harvard Medical School, 1811, Boston, Massachusetts, United States
| | - Jeremy R Beitler
- Columbia University College of Physicians and Surgeons, 12294, Center for Acute Respiratory Failure and Division of Pulmonary, Allergy, and Critical Care Medicine, New York, New York, United States.,NewYork-Presbyterian Hospital, 25065, New York, New York, United States;
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14
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Goligher EC, Costa ELV. Reply to: The Dethroning of 6 ml per kg as the "go-to" Setting in ARDS. Am J Respir Crit Care Med 2021; 204:869-870. [PMID: 34186007 PMCID: PMC8528519 DOI: 10.1164/rccm.202106-1388le] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Ewan C Goligher
- University Health Network, 7989, Department of Medicine, Division of Respirology, Critical Care Program, Toronto, Ontario, Canada.,University of Toronto, 7938, Interdepartmental Division of Critical Care Medicine, Toronto, Ontario, Canada;
| | - Eduardo L V Costa
- Hospital Sírio-Libanês, Research and Education Institute, São Paulo, Brazil
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15
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Abstract
The estimation of pleural pressure with esophageal manometry has been used for decades, and it has been a fertile area of physiology research in healthy subject as well as during mechanical ventilation in patients with lung injury. However, its scarce adoption in clinical practice takes its roots from the (false) ideas that it requires expertise with years of training, that the values obtained are not reliable due to technical challenges or discrepant methods of calculation, and that measurement of esophageal pressure has not proved to benefit patient outcomes. Despites these criticisms, esophageal manometry could contribute to better monitoring, optimization, and personalization of mechanical ventilation from the acute initial phase to the weaning period. This review aims to provide a comprehensive but comprehensible guide addressing the technical aspects of esophageal catheter use, its application in different clinical situations and conditions, and an update on the state of the art with recent studies on this topic and on remaining questions and ways for improvement.
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Affiliation(s)
- Tài Pham
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Ontario, Canada. .,Keenan Research Centre, Li Ka Shing Knowledge Institute, St.Michael's Hospital, Toronto, Ontario, Canada.,Service de médecine intensive-réanimation, Hôpitaux universitaires Paris-Saclay, Hôpital de Bicêtre, APHP, Le Kremlin-Bicêtre, France.,Faculté de Médecine Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Irene Telias
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Ontario, Canada.,Keenan Research Centre, Li Ka Shing Knowledge Institute, St.Michael's Hospital, Toronto, Ontario, Canada.,Department of Medicine, Division of Respirology, University Health Network and Sinai Health System, Toronto, Canada
| | - Jeremy R Beitler
- Center for Acute Respiratory Failure and Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians & Surgeons, New York, New York
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16
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Abstract
PURPOSE OF REVIEW Most clinical trials of lung-protective ventilation have tested one-size-fits-all strategies with mixed results. Data are lacking on how best to tailor mechanical ventilation to patient-specific risk of lung injury. RECENT FINDINGS Risk of ventilation-induced lung injury is determined by biological predisposition to biophysical lung injury and physical mechanical perturbations that concentrate stress and strain regionally within the lung. Recent investigations have identified molecular subphenotypes classified as hyperinflammatory and hypoinflammatory acute respiratory distress syndrome (ARDS), which may have dissimilar risk for ventilation-induced lung injury. Mechanically, gravity-dependent atelectasis has long been recognized to decrease total aerated lung volume available for tidal ventilation, a concept termed the 'ARDS baby lung'. Recent studies have demonstrated that the aerated baby lung also has nonuniform stress/strain distribution, with potentially injurious forces concentrated in zones of heterogeneity where aerated alveoli are adjacent to flooded or atelectatic alveoli. The preponderance of evidence also indicates that current standard-of-care tidal volume management is not universally protective in ARDS. When considering escalation of lung-protective interventions, potential benefits of the intervention should be weighed against tradeoffs of accompanying cointerventions required, for example, deeper sedation or neuromuscular blockade. A precision medicine approach to lung-protection would weigh. SUMMARY A precision medicine approach to lung-protective ventilation requires weighing four key factors in each patient: biological predisposition to biophysical lung injury, mechanical predisposition to biophysical injury accounting for spatial mechanical heterogeneity within the lung, anticipated benefits of escalating lung-protective interventions, and potential unintended adverse effects of mandatory cointerventions.
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17
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De Blasi RA, Fiorelli S. Measurement of esophageal pressure: possible limits to its clinical application. Minerva Anestesiol 2020; 86. [DOI: 10.23736/s0375-9393.20.15040-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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18
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Prospective Observational Study to Evaluate the Effect of Different Levels of Positive End-Expiratory Pressure on Lung Mechanics in Patients with and without Acute Respiratory Distress Syndrome. J Clin Med 2020; 9:jcm9082446. [PMID: 32751791 PMCID: PMC7463691 DOI: 10.3390/jcm9082446] [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: 06/30/2020] [Revised: 07/27/2020] [Accepted: 07/28/2020] [Indexed: 12/12/2022] Open
Abstract
Background: The optimal level of positive end-expiratory pressure is still under debate. There are scare data examining the association of PEEP with transpulmonary pressure (TPP), end-expiratory lung volume (EELV) and intraabdominal pressure in ventilated patients with and without ARDS. Methods: We analyzed lung mechanics in 3 patient groups: group A, patients with ARDS; group B, obese patients (body mass index (BMI) > 30 kg/m2) and group C, a control group. Three levels of PEEP (5, 10, 15 cm H2O) were used to investigate the consequences for lung mechanics. Results: Fifty patients were included, 22 in group A, 18 in group B (BMI 38 ± 2 kg/m2) and 10 in group C. At baseline, oxygenation showed no differences between the groups. Driving pressure (ΔP) and transpulmonary pressure (ΔPL) was higher in group B than in groups A and C at a PEEP of 5 cm H2O (ΔP A: 15 ± 1, B: 18 ± 1, C: 14 ± 1 cm H2O; ΔPL A: 10 ± 1, B: 13 ± 1, C: 9 ± 0 cm H2O). Peak inspiratory pressure (Pinsp) rose in all groups as PEEP increased, but the resulting driving pressure and transpulmonary pressure were reduced, whereas EELV increased. Conclusion: Measuring EELV or TPP allows a personalized approach to lung-protective ventilation.
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20
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Abstract
Respiratory function is fundamental in the practice of anesthesia. Knowledge of basic physiologic principles of respiration assists in the proper implementation of daily actions of induction and maintenance of general anesthesia, delivery of mechanical ventilation, discontinuation of mechanical and pharmacologic support, and return to the preoperative state. The current work provides a review of classic physiology and emphasizes features important to the anesthesiologist. The material is divided in two main sections, gas exchange and respiratory mechanics; each section presents the physiology as the basis of abnormal states. We review the path of oxygen from air to the artery and of carbon dioxide the opposite way, and we have the causes of hypoxemia and of hypercarbia based on these very footpaths. We present the actions of pressure, flow, and volume as the normal determinants of ventilation, and we review the resulting abnormalities in terms of changes of resistance and compliance.
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21
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Abstract
Ventilation-induced lung injury results from mechanical stress and strain that occur during tidal ventilation in the susceptible lung. Classical descriptions of ventilation-induced lung injury have focused on harm from positive pressure ventilation. However, injurious forces also can be generated by patient effort and patient–ventilator interactions. While the role of global mechanics has long been recognized, regional mechanical heterogeneity within the lungs also appears to be an important factor propagating clinically significant lung injury. The resulting clinical phenotype includes worsening lung injury and a systemic inflammatory response that drives extrapulmonary organ failures. Bedside recognition of ventilation-induced lung injury requires a high degree of clinical acuity given its indistinct presentation and lack of definitive diagnostics. Yet the clinical importance of ventilation-induced lung injury is clear. Preventing such biophysical injury remains the most effective management strategy to decrease morbidity and mortality in patients with acute respiratory distress syndrome and likely benefits others at risk.
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Affiliation(s)
- Purnema Madahar
- Center for Acute Respiratory Failure, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Department of Medicine, New York-Presbyterian Hospital, New York City, NY, USA
| | - Jeremy R Beitler
- Center for Acute Respiratory Failure, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, New York City, NY, USA.,Department of Medicine, New York-Presbyterian Hospital, New York City, NY, USA
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22
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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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23
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Cammarota G, Verdina F, Santangelo E, Lauro G, Boniolo E, Tarquini R, Spinelli E, Zanoni M, Garofalo E, Bruni A, Pesenti A, Della Corte F, Navalesi P, Vaschetto R, Mauri T. Oesophageal balloon calibration during pressure support ventilation: a proof of concept study. J Clin Monit Comput 2019; 34:1223-1231. [PMID: 31792760 DOI: 10.1007/s10877-019-00436-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 11/28/2019] [Indexed: 01/20/2023]
Abstract
Oesophageal balloon calibration improves the oesophageal pressure (Pes) assessment during invasive controlled mechanical ventilation. The primary aim of the present investigation was to ascertain the feasibility of oesophageal balloon calibration during pressure support ventilation (PSV). Secondarily, the calibrated Pes (Pescal) was compared to uncalibrated one acquired at 4 ml-filling volume (PesV4), as per manufacturer recommendation. After a naso-gastric tube equipped with oesophageal balloon was correctly positioned in 21 adult patients undergoing invasive volume-controlled ventilation (VCV) for acute hypoxemic respiratory failure, the balloon was progressively inflated, applying a series of end-inspiratory and end-expiratory holds at each filling volume during VCV and PSV. Upon optimal balloon filling volume (Vbest) was identified, Pescal was computed by correcting the Pes measured at Vbest for the oesophageal wall pressure elicited at same filling volume. Finally, end-expiratory and end-inspiratory PesV4 were recorded too. A total of 42 calibrations, 21 per ventilatory mode, were performed. Vbest was 1.9 ± 1.6 ml in VCV and 1.7 ± 1.6 ml in PSV (p = 0.5217). PesV4 was overestimated compared to Pescal at end-expiration and end-inspiration (p <0.0001 for all comparisons) in both VCV (13.4 ± 3.4 cmH2O and 15.4 ± 3 cmH2O vs. 8.5 ± 2.9 cmH2O and 11.4 ± 3 cmH2O) and PSV (14.7 ± 4.2 cmH2O and 17 ± 3.9 cmH2O vs. 8.9 ± 3.4 cmH2O and 12.4 ± 3.9 cmH2O). In PSV, oesophageal balloon calibration is feasible and allows to obtain a reliable Pes assessment compared to uncalibrated approach.
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Affiliation(s)
- Gianmaria Cammarota
- Anaesthesia and General Intensive Care, "Maggiore della Carità" University Hospital, Corso Mazzini18, 28100, Novara, Italy.
| | - Federico Verdina
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Erminio Santangelo
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Gianluigi Lauro
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Ester Boniolo
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Riccardo Tarquini
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Elena Spinelli
- Department of Anaesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Marta Zanoni
- Anaesthesia and General Intensive Care, "Maggiore della Carità" University Hospital, Corso Mazzini18, 28100, Novara, Italy
| | - Eugenio Garofalo
- Department of Medical and Surgical Science, Università Magna Greacia, Catanzaro, Italy
| | - Andrea Bruni
- Department of Medical and Surgical Science, Università Magna Greacia, Catanzaro, Italy
| | - Antonio Pesenti
- Department of Anaesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Francesco Della Corte
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Paolo Navalesi
- Department of Medical and Surgical Science, Università Magna Greacia, Catanzaro, Italy
| | - Rosanna Vaschetto
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Tommaso Mauri
- Department of Anaesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
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24
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Cruces P, Erranz B, Lillo F, Sarabia-Vallejos MA, Iturrieta P, Morales F, Blaha K, Medina T, Diaz F, Hurtado DE. Mapping regional strain in anesthetised healthy subjects during spontaneous ventilation. BMJ Open Respir Res 2019; 6:e000423. [PMID: 31749967 PMCID: PMC6830454 DOI: 10.1136/bmjresp-2019-000423] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 09/17/2019] [Accepted: 10/09/2019] [Indexed: 01/03/2023] Open
Abstract
Introduction Breathing produces a phenomenon of cyclic deformation throughout life. Biomechanically, deformation of the lung is measured as strain. Regional strain recently started to be recognised as a tool in the study of lung pathophysiology, but regional lung strain has not been studied in healthy subjects breathing spontaneously without voluntary or pharmacological control of ventilation. Our aim is to generate three-dimensional (3D) regional strain and heterogeneity maps of healthy rat lungs and describe their changes over time. Methods Micro-CT and image-based biomechanical analysis by finite element approach were carried out in six anaesthetised rats under spontaneous breathing in two different states, at the beginning of the experiment and after 3 hours of observation. 3D regional strain maps were constructed and divided into 10 isovolumetric region-of-interest (ROI) in three directions (apex to base, dorsal to ventral and costal to mediastinal), allowing to regionally analyse the volumetric strain, the strain progression and the strain heterogeneity. To describe in depth these parameters, and systematise their report, we defined regional strain heterogeneity index [1+strain SD ROI(x)]/[1+strain mean ROI(x)] and regional strain progression index [ROI(x)-mean of final strain/ROI(x)-mean of initial strain]. Results We were able to generate 3D regional strain maps of the lung in subjects without respiratory support, showing significant differences among the three analysed axes. We observed a significantly lower regional volumetric strain in the apex sector compared with the base, with no significant anatomical systematic differences in the other directions. This heterogeneity could not be identified with physiological or standard CT methods. There was no progression of the analysed regional volumetric strain when the two time-points were compared. Discussion It is possible to map the regional volumetric strain in the lung for healthy subjects during spontaneous breathing. Regional strain heterogeneity and changes over time can be measured using a CT image-based numerical analysis applying a finite element approach. These results support that healthy lung might have significant regional strain and its spatial distribution is highly heterogeneous. This protocol for CT image acquisition and analysis could be a useful tool for helping to understand the mechanobiology of the lung in many diseases.
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Affiliation(s)
- Pablo Cruces
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile.,Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Benjamin Erranz
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Felipe Lillo
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | | | - Pablo Iturrieta
- Pediatric Intensive Care Unit, Hospital Padre Hurtado, Santiago, Chile
| | - Felipe Morales
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Katherine Blaha
- Pediatric Intensive Care Unit, Hospital Clínico La Florida Dra. Eloisa Diaz Insunza, Santiago, Chile
| | - Tania Medina
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Franco Diaz
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile.,Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Millennium Nucleus for Cardiovascular Magnetic Resonance, Santiago, Chile
| | - Daniel E Hurtado
- Pediatric Intensive Care Unit, Hospital Padre Hurtado, Santiago, Chile.,Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Structural and Geotechnical Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
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25
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Suarez-Sipmann F, Ferrando C, Villar J. PEEP titration guided by transpulmonary pressure: lessons from a negative trial. J Thorac Dis 2019; 11:S1957-S1962. [PMID: 31632797 DOI: 10.21037/jtd.2019.08.03] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Fernando Suarez-Sipmann
- Department of Critical Care Medicine, Hospital Universitario de La Princesa, Madrid, Spain.,CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain.,Department of Surgical Sciences, Hedenstierna Laboratory, Uppsala University, Uppsala, Sweden
| | - Carlos Ferrando
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain.,Department of Anesthesiology and Critical Care, Hospital Clínic, Institut D'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Jesús Villar
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain.,Multidisciplinary Organ Dysfunction Evaluation Research Network (MODERN), Research Unit, Hospital Universitario Dr. Negrín, Las Palmas de Gran Canaria, Spain.,Keenan Research Center for Biomedical Science at the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Canada
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26
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Yoshida T, Amato MBP, Grieco DL, Chen L, Lima CAS, Roldan R, Morais CCA, Gomes S, Costa ELV, Cardoso PFG, Charbonney E, Richard JCM, Brochard L, Kavanagh BP. Esophageal Manometry and Regional Transpulmonary Pressure in Lung Injury. Am J Respir Crit Care Med 2019; 197:1018-1026. [PMID: 29323931 DOI: 10.1164/rccm.201709-1806oc] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Esophageal manometry is the clinically available method to estimate pleural pressure, thus enabling calculation of transpulmonary pressure (Pl). However, many concerns make it uncertain in which lung region esophageal manometry reflects local Pl. OBJECTIVES To determine the accuracy of esophageal pressure (Pes) and in which regions esophageal manometry reflects pleural pressure (Ppl) and Pl; to assess whether lung stress in nondependent regions can be estimated at end-inspiration from Pl. METHODS In lung-injured pigs (n = 6) and human cadavers (n = 3), Pes was measured across a range of positive end-expiratory pressure, together with directly measured Ppl in nondependent and dependent pleural regions. All measurements were obtained with minimal nonstressed volumes in the pleural sensors and esophageal balloons. Expiratory and inspiratory Pl was calculated by subtracting local Ppl or Pes from airway pressure; inspiratory Pl was also estimated by subtracting Ppl (calculated from chest wall and respiratory system elastance) from the airway plateau pressure. MEASUREMENTS AND MAIN RESULTS In pigs and human cadavers, expiratory and inspiratory Pl using Pes closely reflected values in dependent to middle lung (adjacent to the esophagus). Inspiratory Pl estimated from elastance ratio reflected the directly measured nondependent values. CONCLUSIONS These data support the use of esophageal manometry in acute respiratory distress syndrome. Assuming correct calibration, expiratory Pl derived from Pes reflects Pl in dependent to middle lung, where atelectasis usually predominates; inspiratory Pl estimated from elastance ratio may indicate the highest level of lung stress in nondependent "baby" lung, where it is vulnerable to ventilator-induced lung injury.
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Affiliation(s)
- Takeshi Yoshida
- 1 Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,2 Translational Medicine, Departments of Critical Care Medicine and Anesthesia, Hospital for Sick Children, and.,3 Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada
| | | | - Domenico Luca Grieco
- 1 Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,2 Translational Medicine, Departments of Critical Care Medicine and Anesthesia, Hospital for Sick Children, and.,5 Department of Anesthesiology and Intensive Care Medicine, Catholic University of The Sacred Heart, Fondazione "Policlinico universitario A. Gemelli," Rome, Italy.,6 Cardiac Arrest and Ventilation International Association for Research, Laboratoire d'anatomie, Université du Québec à Trois-Rivières et Centre Intégré Universitaire de Santé et de Services Sociaux de la Mauricie-et-du-Centre-du-Québec, Trois-Rivières, Canada
| | - Lu Chen
- 1 Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,2 Translational Medicine, Departments of Critical Care Medicine and Anesthesia, Hospital for Sick Children, and
| | | | - Rollin Roldan
- 4 Divisao de Pneumologia and.,7 Unidad de Cuidados Intensivos, Hospital Rebagliati, Lima, Perú
| | | | | | | | - Paulo F G Cardoso
- 8 Disciplina de Cirurgia Torácica, Instituto do Coração, Hospital das Clinicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Emmanuel Charbonney
- 6 Cardiac Arrest and Ventilation International Association for Research, Laboratoire d'anatomie, Université du Québec à Trois-Rivières et Centre Intégré Universitaire de Santé et de Services Sociaux de la Mauricie-et-du-Centre-du-Québec, Trois-Rivières, Canada.,9 Centre de Recherche de l'Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada; and
| | - Jean-Christophe M Richard
- 6 Cardiac Arrest and Ventilation International Association for Research, Laboratoire d'anatomie, Université du Québec à Trois-Rivières et Centre Intégré Universitaire de Santé et de Services Sociaux de la Mauricie-et-du-Centre-du-Québec, Trois-Rivières, Canada.,10 Department of Pre-Hospital and Emergency Medicine, General Hospital of Annecy, Annecy, France
| | - Laurent Brochard
- 1 Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada.,3 Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada.,6 Cardiac Arrest and Ventilation International Association for Research, Laboratoire d'anatomie, Université du Québec à Trois-Rivières et Centre Intégré Universitaire de Santé et de Services Sociaux de la Mauricie-et-du-Centre-du-Québec, Trois-Rivières, Canada
| | - Brian P Kavanagh
- 2 Translational Medicine, Departments of Critical Care Medicine and Anesthesia, Hospital for Sick Children, and.,3 Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada
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27
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Affiliation(s)
- Stefan Lundin
- Department of Anesthesiology and Intensive Care, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Per Persson
- Department of Anesthesiology and Intensive Care, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Anders Larsson
- Hedenstierna Laboratory, Uppsala University, Uppsala, Sweden
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28
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Bergez M, Fritsch N, Tran-Van D, Saghi T, Bounkim T, Gentile A, Labadie P, Fontaine B, Ouattara A, Rozé H. PEEP titration in moderate to severe ARDS: plateau versus transpulmonary pressure. Ann Intensive Care 2019; 9:81. [PMID: 31312921 PMCID: PMC6635540 DOI: 10.1186/s13613-019-0554-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/24/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Although lung protection with low tidal volume and limited plateau pressure (Pplat) improves survival in acute respiratory distress syndrome patients (ARDS), the best way to set positive end-expiratory pressure (PEEP) is still debated. METHODS This study aimed to compare two strategies using individual PEEP based on a maximum Pplat (28-30 cmH2O, the Express group) or on keeping end-expiratory transpulmonary pressure positive (0-5 cmH2O, PLexpi group). We estimated alveolar recruitment (Vrec), end-expiratory lung volume and alveolar distension based on elastance-related end-inspiratory transpulmonary pressure (PL,EL). RESULTS Nineteen patients with moderate to severe ARDS (PaO2/FiO2 < 150 mmHg) were included with a baseline PEEP of 7.0 ± 1.8 cmH2O and a PaO2/FiO2 of 91.2 ± 31.2 mmHg. PEEP and oxygenation increased significantly from baseline with both protocols; PEEP Express group was 14.2 ± 3.6 cmH2O versus 16.7 ± 5.9 cmH2O in PLexpi group. No patient had the same PEEP with the two protocols. Vrec was higher with the latter protocol (299 [0 to 875] vs. 222 [47 to 483] ml, p = 0.049) and correlated with improved oxygenation (R2 = 0.45, p = 0.002). Two and seven patients in the Express and PL,expi groups, respectively, had PL,EL > 25 cmH2O. CONCLUSIONS There is a great heterogeneity of PLexpi when Pplat is used to titrate PEEP but with limited risk of over-distension. A PEEP titration for a moderate positive level of PLexpi might slightly improve alveolar recruitment and oxygenation but increases the risk of over-distension in one-third of patients.
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Affiliation(s)
- Marie Bergez
- Anaesthesia and Intensive Care Unit, Robert Picque Military Teaching Hospital, Villenave d'Ornon, France
| | - Nicolas Fritsch
- Anaesthesia and Intensive Care Unit, Robert Picque Military Teaching Hospital, Villenave d'Ornon, France
| | - David Tran-Van
- Anaesthesia and Intensive Care Unit, Robert Picque Military Teaching Hospital, Villenave d'Ornon, France
| | - Tahar Saghi
- Intensive Care Unit, North Bordeaux Aquitaine Clinic, Bordeaux, France
| | - Tan Bounkim
- Medical and Surgical Intensive Care, Saint Joseph Saint Luc Teaching Hospital, Lyon, France
| | - Ariane Gentile
- Anaesthesia and Intensive Care Unit, Robert Picque Military Teaching Hospital, Villenave d'Ornon, France
| | - Philippe Labadie
- Anaesthesia and Intensive Care Unit, Robert Picque Military Teaching Hospital, Villenave d'Ornon, France
| | - Bruno Fontaine
- Anaesthesia and Intensive Care Unit, Robert Picque Military Teaching Hospital, Villenave d'Ornon, France
| | - Alexandre Ouattara
- Magellan Medico-Surgical Center, South Department of Anaesthesia and Critical Care, CHU Bordeaux, 33000, Bordeaux, France.,Biology of Cardiovascular Diseases, INSERM, UMR 1034, Univ. Bordeaux, 33600, Pessac, France
| | - Hadrien Rozé
- Magellan Medico-Surgical Center, South Department of Anaesthesia and Critical Care, CHU Bordeaux, 33000, Bordeaux, France.
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Gattinoni L, Giosa L, Bonifazi M, Pasticci I, Busana M, Macri M, Romitti F, Vassalli F, Quintel M. Targeting transpulmonary pressure to prevent ventilator-induced lung injury. Expert Rev Respir Med 2019; 13:737-746. [PMID: 31274034 DOI: 10.1080/17476348.2019.1638767] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Introduction: Transpulmonary pressure (PL) is the pressure distending the lung. This pressure equals the stress which develops into the parenchyma at each insufflation and it depends, for a given airway pressure, on the relationship between the lung and the chest wall elastance: a given stress is associated to a given strain, therefor PL is strictly related to ventilator-induced lung injury (VILI). Insufficient knowledge and increased workload account for its limited use in the clinical setting: indeed, the current recommendations for protective ventilation still rely only on the pressures applied to the respiratory system in total (Plateau pressure), without a direct measurement of the real lung stress. Areas covered: We reviewed the significance, the assessment, the application and the limits of transpulmonary pressure in the clinical setting. Expert opinion: Transpulmonary pressure represents a physiologically sound safety limit for mechanical ventilation that should be measured and targeted at least in the most severe ARDS patients. Targeting transpulmonary pressure means 'personalizing' the ventilatory settings.
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Affiliation(s)
- Luciano Gattinoni
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Lorenzo Giosa
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Matteo Bonifazi
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Iacopo Pasticci
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Mattia Busana
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Matteo Macri
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Federica Romitti
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Francesco Vassalli
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
| | - Michael Quintel
- a Department of Anaesthesiology, Emergency and Intensive Care Medicine, University of Göttingen , Göttingen , Germany
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30
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Williams EC, Motta-Ribeiro GC, Vidal Melo MF. Driving Pressure and Transpulmonary Pressure: How Do We Guide Safe Mechanical Ventilation? Anesthesiology 2019; 131:155-163. [PMID: 31094753 PMCID: PMC6639048 DOI: 10.1097/aln.0000000000002731] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The physiological concept, pathophysiological implications and clinical relevance and application of driving pressure and transpulmonary pressure to prevent ventilator-induced lung injury are discussed.
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Affiliation(s)
- Elizabeth C Williams
- From the Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts. Current Affiliation: Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, Maryland (E.C.W.)
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31
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32
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Clinical Deployment of the Esophageal Balloon Catheter-Making the Case. Crit Care Med 2019; 45:1419-1421. [PMID: 28708686 DOI: 10.1097/ccm.0000000000002490] [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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33
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Beitler JR, Sarge T, Banner-Goodspeed VM, Gong MN, Cook D, Novack V, Loring SH, Talmor D. Effect of Titrating Positive End-Expiratory Pressure (PEEP) With an Esophageal Pressure-Guided Strategy vs an Empirical High PEEP-Fio2 Strategy on Death and Days Free From Mechanical Ventilation Among Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial. JAMA 2019; 321:846-857. [PMID: 30776290 PMCID: PMC6439595 DOI: 10.1001/jama.2019.0555] [Citation(s) in RCA: 243] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
IMPORTANCE Adjusting positive end-expiratory pressure (PEEP) to offset pleural pressure might attenuate lung injury and improve patient outcomes in acute respiratory distress syndrome (ARDS). OBJECTIVE To determine whether PEEP titration guided by esophageal pressure (PES), an estimate of pleural pressure, was more effective than empirical high PEEP-fraction of inspired oxygen (Fio2) in moderate to severe ARDS. DESIGN, SETTING, AND PARTICIPANTS Phase 2 randomized clinical trial conducted at 14 hospitals in North America. Two hundred mechanically ventilated patients aged 16 years and older with moderate to severe ARDS (Pao2:Fio2 ≤200 mm Hg) were enrolled between October 31, 2012, and September 14, 2017; long-term follow-up was completed July 30, 2018. INTERVENTIONS Participants were randomized to PES-guided PEEP (n = 102) or empirical high PEEP-Fio2 (n = 98). All participants received low tidal volumes. MAIN OUTCOMES AND MEASURES The primary outcome was a ranked composite score incorporating death and days free from mechanical ventilation among survivors through day 28. Prespecified secondary outcomes included 28-day mortality, days free from mechanical ventilation among survivors, and need for rescue therapy. RESULTS Two hundred patients were enrolled (mean [SD] age, 56 [16] years; 46% female) and completed 28-day follow-up. The primary composite end point was not significantly different between treatment groups (probability of more favorable outcome with PES-guided PEEP: 49.6% [95% CI, 41.7% to 57.5%]; P = .92). At 28 days, 33 of 102 patients (32.4%) assigned to PES-guided PEEP and 30 of 98 patients (30.6%) assigned to empirical PEEP-Fio2 died (risk difference, 1.7% [95% CI, -11.1% to 14.6%]; P = .88). Days free from mechanical ventilation among survivors was not significantly different (median [interquartile range]: 22 [15-24] vs 21 [16.5-24] days; median difference, 0 [95% CI, -1 to 2] days; P = .85). Patients assigned to PES-guided PEEP were significantly less likely to receive rescue therapy (4/102 [3.9%] vs 12/98 [12.2%]; risk difference, -8.3% [95% CI, -15.8% to -0.8%]; P = .04). None of the 7 other prespecified secondary clinical end points were significantly different. Adverse events included gross barotrauma, which occurred in 6 patients with PES-guided PEEP and 5 patients with empirical PEEP-Fio2. CONCLUSIONS AND RELEVANCE Among patients with moderate to severe ARDS, PES-guided PEEP, compared with empirical high PEEP-Fio2, resulted in no significant difference in death and days free from mechanical ventilation. These findings do not support PES-guided PEEP titration in ARDS. TRIAL REGISTRATION ClinicalTrials.gov Identifier NCT01681225.
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Affiliation(s)
- Jeremy R. Beitler
- Center for Acute Respiratory Failure and Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians & Surgeons, New York, New York
| | - Todd Sarge
- Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Valerie M. Banner-Goodspeed
- Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Michelle N. Gong
- Division of Critical Care Medicine, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York
| | - Deborah Cook
- Department of Medicine, St Joseph’s Hospital and McMaster University, Hamilton, Ontario, Canada
| | - Victor Novack
- Soroka Clinical Research Center, Soroka University Medical Center, Beer-Sheva, Israel
| | - Stephen H. Loring
- Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Daniel Talmor
- Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
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Bates AJ, Higano NS, Hysinger EB, Fleck RJ, Hahn AD, Fain SB, Kingma PS, Woods JC. Quantitative Assessment of Regional Dynamic Airway Collapse in Neonates via Retrospectively Respiratory-Gated 1 H Ultrashort Echo Time MRI. J Magn Reson Imaging 2019; 49:659-667. [PMID: 30252988 PMCID: PMC6375762 DOI: 10.1002/jmri.26296] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/27/2018] [Accepted: 07/27/2018] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Neonatal dynamic tracheal collapse (tracheomalacia, TM) is a common and serious comorbidity in infants, particularly those with chronic lung disease of prematurity (bronchopulmonary dysplasia, BPD) or congenital airway or lung-related conditions such as congenital diaphragmatic hernia (CDH), but the underlying pathology, impact on clinical outcomes, and response to therapy are not well understood. There is a pressing clinical need for an accurate, objective, and safe assessment of neonatal TM. PURPOSE To use retrospectively respiratory-gated ultrashort echo-time (UTE) MRI to noninvasively analyze moving tracheal anatomy for regional, quantitative evaluation of dynamic airway collapse in quiet-breathing, nonsedated neonates. STUDY TYPE Prospective. POPULATION/SUBJECTS Twenty-seven neonatal subjects with varying respiratory morbidities (control, BPD, CDH, abnormal polysomnogram). FIELD STRENGTH/SEQUENCE High-resolution 3D radial UTE MRI (0.7 mm isotropic) on 1.5T scanner sited in the neonatal intensive care unit. ASSESSMENT Images were retrospectively respiratory-gated using the motion-modulated time-course of the k-space center. Tracheal surfaces were generated from segmentations of end-expiration/inspiration images and analyzed geometrically along the tracheal length to calculate percent-change in luminal cross-sectional area (A % ) and ratio of minor-to-major diameters at end-expiration (r D,exp ). Geometric results were compared to clinically available bronchoscopic findings (n = 14). STATISTICAL TESTS Two-sample t-test. RESULTS Maximum A % significantly identified subjects with/without a bronchoscopic TM diagnosis (with: 46.9 ± 10.0%; without: 27.0 ± 5.8%; P < 0.001), as did minimum r D,exp (with: 0.346 ± 0.146; without: 0.671 ± 0.218; P = 0.008). Subjects with severe BPD exhibited a far larger range of minimum r D,exp than subjects with mild/moderate BPD or controls (0.631 ± 0.222, 0.782 ± 0.075, and 0.776 ± 0.030, respectively), while minimum r D,exp was reduced in CDH subjects (0.331 ± 0.171) compared with controls (P < 0.001). DATA CONCLUSION Respiratory-gated UTE MRI can quantitatively and safely evaluate neonatal dynamic tracheal collapse, as validated with the clinical standard of bronchoscopy, without requiring invasive procedures, anesthesia, or ionizing radiation. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:659-667.
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Affiliation(s)
- Alister J Bates
- Upper Airway Center, Division of Pulmonary Medicine, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
| | - Nara S Higano
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
| | - Erik B Hysinger
- Upper Airway Center, Division of Pulmonary Medicine, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
| | - Robert J Fleck
- Upper Airway Center, Division of Pulmonary Medicine, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
- Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
| | - Andrew D Hahn
- Department of Medical Physics, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Sean B Fain
- Department of Medical Physics, University of Wisconsin - Madison, Madison, Wisconsin, USA
- Department of Radiology, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Paul S Kingma
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
- Department of Neonatology and Pulmonary Biology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
| | - Jason C Woods
- Upper Airway Center, Division of Pulmonary Medicine, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati, Cincinnati, Ohio, USA
- Department of Radiology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA
- Departments of Radiology and Physics, University of Cincinnati, Cincinnati, Ohio, USA
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Baedorf Kassis E, Loring SH, Talmor D. Should we titrate peep based on end-expiratory transpulmonary pressure?-yes. ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:390. [PMID: 30460264 DOI: 10.21037/atm.2018.06.35] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ventilator management of patients with acute respiratory distress syndrome (ARDS) has been characterized by implementation of basic physiology principles by minimizing harmful distending pressures and preventing lung derecruitment. Such strategies have led to significant improvements in outcomes. Positive end expiratory pressure (PEEP) is an important part of a lung protective strategy but there is no standardized method to set PEEP level. With widely varying types of lung injury, body habitus and pulmonary mechanics, the use of esophageal manometry has become important for personalization and optimization of mechanical ventilation in patients with ARDS. Esophageal manometry estimates pleural pressures, and can be used to differentiate the chest wall and lung (transpulmonary) contributions to the total respiratory system mechanics. Elevated pleural pressures may result in negative transpulmonary pressures at end expiration, leading to lung collapse. Measuring the esophageal pressures and adjusting PEEP to make transpulmonary pressures positive can decrease atelectasis, derecruitment of lung, and cyclical opening and closing of airways and alveoli, thus optimizing lung mechanics and oxygenation. Although there is some spatial and positional artifact, esophageal pressures in numerous animal and human studies in healthy, obese and critically ill patients appear to be a good estimate for the "effective" pleural pressure. Multiple studies have illustrated the benefit of using esophageal pressures to titrate PEEP in patients with obesity and with ARDS. Esophageal pressure monitoring provides a window into the unique physiology of a patient and helps improve clinical decision making at the bedside.
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Affiliation(s)
- Elias Baedorf Kassis
- Division of Pulmonary and Critical Care, Beth Israel Deaconess Medical Center and Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Stephen H Loring
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Daniel Talmor
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
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Umbrello M, Chiumello D. Interpretation of the transpulmonary pressure in the critically ill patient. ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:383. [PMID: 30460257 DOI: 10.21037/atm.2018.05.31] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mechanical ventilation is a life-saving procedure, which takes over the function of the respiratory muscles while buying time for healing to take place. However, it can also promote or worsen lung injury, so that careful monitoring of respiratory mechanics is suggested to titrate the level of support and avoid injurious pressures and volumes to develop. Standard monitoring includes flow, volume and airway pressure (Paw). However, Paw represents the pressure acting on the respiratory system as a whole, and does not allow to differentiate the part of pressure that is spent di distend the chest wall. Moreover, if spontaneous breathing efforts are allowed, the Paw is the sum of that applied by the ventilator and that generated by the patient. As a consequence, monitoring of Paw has significant shortcomings. Assessment of esophageal pressure (Pes), as a surrogate for pleural pressure (Ppl), may allow the clinicians to discriminate between the elastic behaviour of the lung and the chest wall, and to calculate the degree of spontaneous respiratory effort. In the present review, the characteristics and limitations of airway and transpulmonary pressure monitoring will be presented; we will highlight the different assumptions underlying the various methods for measuring transpulmonary pressure (i.e., the elastance-derived and the release-derived method, and the direct measurement), as well as the potential application of transpulmonary pressure assessment during both controlled and spontaneous/assisted mechanical ventilation in critically ill patients.
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Affiliation(s)
- Michele Umbrello
- UOC Anestesia e Rianimazione, Ospedale San Paolo - ASST Santi Paolo e Carlo, Milano, Italy
| | - Davide Chiumello
- UOC Anestesia e Rianimazione, Ospedale San Paolo - ASST Santi Paolo e Carlo, Milano, Italy.,Dipartimento di Scienze della Salute, Università degli Studi di Milano, Milano, Italy
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37
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Stenqvist O, Persson P, Lundin S. Can we estimate transpulmonary pressure without an esophageal balloon?-yes. ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:392. [PMID: 30460266 DOI: 10.21037/atm.2018.06.05] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A protective ventilation strategy is based on separation of lung and chest wall mechanics and determination of transpulmonary pressure. So far, this has required esophageal pressure measurement, which is cumbersome, rarely used clinically and associated with lack of consensus on the interpretation of measurements. We have developed an alternative method based on a positive end expiratory pressure (PEEP) step procedure where the PEEP-induced change in end-expiratory lung volume is determined by the ventilator pneumotachograph. In pigs, lung healthy patients and acute lung injury (ALI) patients, it has been verified that the determinants of the change in end-expiratory lung volume following a PEEP change are the size of the PEEP step and the elastic properties of the lung, ∆PEEP × Clung. As a consequence, lung compliance can be calculated as the change in end-expiratory lung volume divided by the change in PEEP and esophageal pressure measurements are not needed. When lung compliance is determined in this way, transpulmonary driving pressure can be calculated on a breath-by-breath basis. As the end-expiratory transpulmonary pressure increases as much as PEEP is increased, it is also possible to determine the end-inspiratory transpulmonary pressure at any PEEP level. Thus, the most crucial factors of ventilator induced lung injury can be determined by a simple PEEP step procedure. The measurement procedure can be repeated with short intervals, which makes it possible to follow the course of the lung disease closely. By the PEEP step procedure we may also obtain information (decision support) on the mechanical consequences of changes in PEEP and tidal volume performed to improve oxygenation and/or carbon dioxide removal.
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Affiliation(s)
- Ola Stenqvist
- Department of Anesthesiology and Intensive Care Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Per Persson
- Department of Anesthesiology and Intensive Care Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Stefan Lundin
- Department of Anesthesiology and Intensive Care Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
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Marini JJ. Should we titrate positive end-expiratory pressure based on an end-expiratory transpulmonary pressure? ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:391. [PMID: 30460265 DOI: 10.21037/atm.2018.08.22] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Arguments continue to swirl regarding the need for and best method of positive end-expiratory pressure (PEEP) titration. An appropriately conducted decremental method that uses modest peak pressures for the recruiting maneuver (RM), a lung protective tidal excursion, relatively small PEEP increments and appropriate timing intervals is currently the most logical and attractive option, particularly when the esophageal balloon pressure (Pes) is used to calculate transpulmonary driving pressures relevant to the lung. The setting of PEEP by the Pes-guided end-expiratory pressure at the 'polarity transition' point of the transmural end-expiratory pressure is quite relevant to the locale of the esophageal balloon catheter. Its desirability, however, is limited by its tendency to encourage PEEP levels that are higher than most other PEEP titration methods. These Pes-set PEEP values promote higher mean airway pressures and are likely to be unnecessary when small tidal driving pressures are in use. Because high airway pressures increase global lung stress and risk hemodynamic compromise, the Pes-determined PEEP would seem associated with a relatively high hazard to benefit ratio for many patients.
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Affiliation(s)
- John J Marini
- Department of Pulmonary and Critical Care Medicine, University of Minnesota, Minneapolis, MN, USA
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Obi ON, Mazer M, Bangley C, Kassabo Z, Saadah K, Trainor W, Stephens K, Rice PL, Shaw R. Obesity and Weaning from Mechanical Ventilation-An Exploratory Study. CLINICAL MEDICINE INSIGHTS-CIRCULATORY RESPIRATORY AND PULMONARY MEDICINE 2018; 12:1179548418801004. [PMID: 30245572 PMCID: PMC6144576 DOI: 10.1177/1179548418801004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 08/22/2018] [Indexed: 12/25/2022]
Abstract
Introduction Obesity is associated with increased risk of hypercapnic respiratory failure, prolonged duration on mechanical ventilation, and extended weaning periods. Objective Pilot study to determine whether morbidly obese adult tracheotomized subjects (body mass index [BMI] ⩾ 40) can be more efficiently weaned from the ventilator by optimizing their positive end-expiratory pressure (PEEP) using either an esophageal balloon or the best achieved static effective compliance. Methods We randomly assigned 25 morbidly obese adult tracheotomized subjects (median [interquartile range] BMI 53.4 [26.4]; range 40.4-113.8) to 1 of 2 methods of setting PEEP; using either titration guided by esophageal balloon to overcome negative transpulmonary pressure (Ptp) (goal Ptp 0-5 cmH2O) (ESO group) or titration to maximize static effective lung compliance (Cstat group). Our outcomes of interest were number of subjects weaned by day 30 and time to wean. Results At day 30, there was no significant difference in percentage of subjects weaned. 8/13 subjects (62%) in the ESO Group were weaned vs. 9/12(75%) in the Cstat Group (P = 0.67). Among the 17 subjects who weaned, median time to ventilator liberation was significantly shorter in the ESO group: 3.5 days vs Cstat group 14 days (P = .01). Optimal PEEP in the ESO and Cstat groups was similar (ESO mean ± SD = 26.5 ± 5.7 cmH2O and Cstat 24.2 ± 7 cmH2O (P = .38). Conclusions Optimization of PEEP using esophageal balloon to achieve positive transpulmonary pressure did not change the proportion of patients weaned. Among patients who weaned, use of the esophageal balloon resulted in faster liberation from mechanical ventilation. There were no adverse consequences of the high PEEP (mean 25.4; range 13-37 cmH2O) used in our study. The study was approved by the Institutional Review Board at our institution (UMCIRB#10-0343) and registered with clinicaltrials.gov (NCT02323009).
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Affiliation(s)
- Ogugua Ndili Obi
- Division of Pulmonary, Critical Care, and Sleep Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Mark Mazer
- Division of Pulmonary, Critical Care, and Sleep Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Charles Bangley
- Department of Respiratory Care, Vidant Medical Center, Greenville, NC, USA
| | - Zuheir Kassabo
- Division of Pulmonary, Critical Care, and Sleep Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Khalid Saadah
- Division of Pulmonary, Critical Care, and Sleep Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Wayne Trainor
- Department of Respiratory Care, Vidant Medical Center, Greenville, NC, USA
| | - Kenneth Stephens
- Department of Respiratory Care, Vidant Medical Center, Greenville, NC, USA
| | - Patricia L Rice
- Division of Pulmonary, Critical Care, and Sleep Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Robert Shaw
- Division of Pulmonary, Critical Care, and Sleep Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
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Dorado JH, Accoce M, Plotnikow G. Chest wall effect on the monitoring of respiratory mechanics in acute respiratory distress syndrome. Rev Bras Ter Intensiva 2018; 30:208-218. [PMID: 29995087 PMCID: PMC6031425 DOI: 10.5935/0103-507x.20180038] [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: 07/16/2017] [Accepted: 11/14/2017] [Indexed: 11/23/2022] Open
Abstract
The respiratory system mechanics depend on the characteristics of the lung and
chest wall and their interaction. In patients with acute respiratory distress
syndrome under mechanical ventilation, the monitoring of airway plateau pressure
is fundamental given its prognostic value and its capacity to assess pulmonary
stress. However, its validity can be affected by changes in mechanical
characteristics of the chest wall, and it provides no data to correctly titrate
positive end-expiratory pressure by restoring lung volume. The chest wall effect
on respiratory mechanics in acute respiratory distress syndrome has not been
completely described, and it has likely been overestimated, which may lead to
erroneous decision making. The load imposed by the chest wall is negligible when
the respiratory system is insufflated with positive end-expiratory pressure.
Under dynamic conditions, moving this structure demands a pressure change whose
magnitude is related to its mechanical characteristics, and this load remains
constant regardless of the volume from which it is insufflated. Thus, changes in
airway pressure reflect changes in the lung mechanical conditions. Advanced
monitoring could be reserved for patients with increased intra-abdominal
pressure in whom a protective mechanical ventilation strategy cannot be
implemented. The estimates of alveolar recruitment based on respiratory system
mechanics could reflect differences in chest wall response to insufflation and
not actual alveolar recruitment.
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Affiliation(s)
- Javier Hernán Dorado
- Capítulo de Kinesiología Intensivista, Sociedad Argentina de Terapia Intensiva - Buenos Aires, Argentina.,Sanatorio Anchorena - Buenos Aires, Argentina.,Hospital General de Agudos Carlos G. Durand - Buenos Aires, Argentina
| | - Matías Accoce
- Capítulo de Kinesiología Intensivista, Sociedad Argentina de Terapia Intensiva - Buenos Aires, Argentina.,Hospital de Quemados - Buenos Aires, Argentina.,Sanatorio Anchorena San Martín - Buenos Aires, Argentina
| | - Gustavo Plotnikow
- Capítulo de Kinesiología Intensivista, Sociedad Argentina de Terapia Intensiva - Buenos Aires, Argentina.,Sanatorio Anchorena - Buenos Aires, Argentina
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Sun XM, Chen GQ, Huang HW, He X, Yang YL, Shi ZH, Xu M, Zhou JX. Use of esophageal balloon pressure-volume curve analysis to determine esophageal wall elastance and calibrate raw esophageal pressure: a bench experiment and clinical study. BMC Anesthesiol 2018; 18:21. [PMID: 29444644 PMCID: PMC5813414 DOI: 10.1186/s12871-018-0488-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 02/08/2018] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Accurate measurement of esophageal pressure (Pes) depends on proper filling of the balloon. Esophageal wall elastance (Ees) may also influence the measurement. We examined the estimation of balloon-surrounding elastance in a bench model and investigated a simplified calibrating procedure of Pes in a balloon with relatively small volume. METHODS The Cooper balloon catheter (geometric volume of 2.8 ml) was used in the present study. The balloon was progressively inflated in different gas-tight glass chambers with different inner volumes. Chamber elastance was measured by the fitting of chamber pressure and balloon volume. Balloon pressure-volume (P-V) curves were obtained, and the slope of the intermediate linear section was defined as the estimated chamber elastance. Balloon volume tests were also performed in 40 patients under controlled ventilation. The slope of the intermediate linear section on the end-expiratory esophageal P-V curve was calculated as the Ees. The balloon volume with the largest Pes tidal swing was defined as the best volume. Pressure generated by the esophageal wall during balloon inflation (Pew) was estimated as the product of Ees and best volume. Because the clinical intermediate linear section enclosed filling volume of 0.6 to 1.4 ml in each of the patient, we simplified the estimation of Ees by only using parameters at these two filling volumes. RESULTS In the bench experiment, bias (lower and upper limits of agreement) was 0.5 (0.2 to 0.8) cmH2O/ml between the estimated and measured chamber elastance. The intermediate linear section on the clinical and bench P-V curves resembled each other. Median (interquartile range) Ees was 3.3 (2.5-4.1) cmH2O/ml. Clinical best volume was 1.0 (0.8-1.2) ml and ranged from 0.6 to 1.4 ml. Estimated Pew at the best volume was 2.8 (2.5-3.5) cmH2O with a maximum value of 5.2 cmH2O. Compared with the conventional method, bias (lower and upper limits of agreement) of Ees estimated by the simple method was - 0.1 (- 0.7 to 0.6) cmH2O/ml. CONCLUSIONS The slope of the intermediate linear section on the balloon P-V curve correlated with the balloon-surrounding elastance. The estimation of Ees and calibration of Pes were feasible for a small-volume-balloon. TRIAL REGISTRATION Identifier NCT02976844 . Retrospectively registered on 29 November 2016.
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Affiliation(s)
- Xiu-Mei Sun
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China
| | - Guang-Qiang Chen
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China
| | - Hua-Wei Huang
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China
| | - Xuan He
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China
| | - Yan-Lin Yang
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China
| | - Zhong-Hua Shi
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China
| | - Ming Xu
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China
| | - Jian-Xin Zhou
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Address: No 6, Tiantan Xili, Dongcheng district, Beijing, 100050, China.
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42
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Gudmundsson M, Perchiazzi G, Pellegrini M, Vena A, Hedenstierna G, Rylander C. Atelectasis is inversely proportional to transpulmonary pressure during weaning from ventilator support in a large animal model. Acta Anaesthesiol Scand 2018; 62:94-104. [PMID: 29058315 DOI: 10.1111/aas.13015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 09/22/2017] [Accepted: 09/30/2017] [Indexed: 01/27/2023]
Abstract
BACKGROUND In mechanically ventilated, lung injured, patients without spontaneous breathing effort, atelectasis with shunt and desaturation may appear suddenly when ventilator pressures are decreased. It is not known how such a formation of atelectasis is related to transpulmonary pressure (PL ) during weaning from mechanical ventilation when the spontaneous breathing effort is increased. If the relation between PL and atelectasis were known, monitoring of PL might help to avoid formation of atelectasis and cyclic collapse during weaning. The main purpose of this study was to determine the relation between PL and atelectasis in an experimental model representing weaning from mechanical ventilation. METHODS Dynamic transverse computed tomography scans were acquired in ten anaesthetized, surfactant-depleted pigs with preserved spontaneous breathing, as ventilator support was lowered by sequentially reducing inspiratory pressure and positive end expiratory pressure in steps. The volumes of gas and atelectasis in the lungs were correlated with PL obtained using oesophageal pressure recordings. Work of breathing (WOB) was assessed from Campbell diagrams. RESULTS Gradual decrease in PL in both end-expiration and end-inspiration caused a proportional increase in atelectasis and decrease in the gas content (linear mixed model with an autoregressive correlation matrix; P < 0.001) as the WOB increased. However, cyclic alveolar collapse during tidal ventilation did not increase significantly. CONCLUSION We found a proportional correlation between atelectasis and PL during the 'weaning process' in experimental mild lung injury. If confirmed in the clinical setting, a gradual tapering of ventilator support can be recommended for weaning without risk of sudden formation of atelectasis.
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Affiliation(s)
- M. Gudmundsson
- Department of Anaesthesiology and Intensive Care Medicine; Institute of Clinical Sciences; Sahlgrenska Academy; University of Gothenburg; Gothenburg Sweden
| | - G. Perchiazzi
- Hedenstierna Laboratory; Institute of Medical Sciences; Uppsala University; Uppsala Sweden
| | - M. Pellegrini
- Hedenstierna Laboratory; Institute of Medical Sciences; Uppsala University; Uppsala Sweden
| | - A. Vena
- Department of Emergency and Organ Transplant; Bari University; Bari Italy
| | - G. Hedenstierna
- Hedenstierna Laboratory; Institute of Medical Sciences; Uppsala University; Uppsala Sweden
| | - C. Rylander
- Department of Anaesthesiology and Intensive Care Medicine; Institute of Clinical Sciences; Sahlgrenska Academy; University of Gothenburg; Gothenburg Sweden
- Hedenstierna Laboratory; Institute of Medical Sciences; Uppsala University; Uppsala Sweden
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43
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Esophageal pressure: research or clinical tool? Med Klin Intensivmed Notfmed 2017; 113:13-20. [PMID: 29134245 DOI: 10.1007/s00063-017-0372-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 10/09/2017] [Indexed: 10/18/2022]
Abstract
Esophageal manometry has traditionally been utilized for respiratory physiology research, but clinicians have recently found numerous applications within the intensive care unit. Esophageal pressure (PEs) is a surrogate for pleural pressures (PPl), and the difference between airway pressure (PAO) and PEs provides a good estimate for the pressure across the lung also known as the transpulmonary pressure (PL). Differentiating the effects of mechanical ventilation and spontaneous breathing on the respiratory system, chest wall, and across the lung allows for improved personalization in clinical decision making. Measuring PL in acute respiratory distress syndrome (ARDS) may help set positive end expiratory pressure (PEEP) to prevent derecruitment and atelectrauma, while assuring peak pressures do not cause over distension during tidal breathing and recruitment maneuvers. Monitoring PEs allows improved insight into patient-ventilator interactions and may help in decisions to adjust sedation and paralytics to correct dyssynchrony. Intrinsic PEEP (auto-PEEP) may be monitored using esophageal manometry, which may also improve patient comfort and synchrony with the ventilator. Finally, during weaning, PEs may be used to better predict weaning success and allow for rapid intervention during failure. Improved consistency in definition and terminology and further outcomes research is needed to encourage more widespread adoption; however, with clear clinical benefit and increased ease of use, it appears time to reintroduce basic physiology into personalized ventilator management in the intensive care unit.
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44
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Herrmann J, Tawhai MH, Kaczka DW. Parenchymal strain heterogeneity during oscillatory ventilation: why two frequencies are better than one. J Appl Physiol (1985) 2017; 124:653-663. [PMID: 29051332 DOI: 10.1152/japplphysiol.00615.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
High-frequency oscillatory ventilation (HFOV) relies on low tidal volumes cycled at supraphysiological rates, producing fundamentally different mechanisms for gas transport and exchange compared with conventional mechanical ventilation. Despite the appeal of using low tidal volumes to mitigate the risks of ventilator-induced lung injury, HFOV has not improved mortality for most clinical indications. This may be due to nonuniform and frequency-dependent distribution of flow throughout the lung. The goal of this study was to compare parenchymal strain heterogeneity during eucapnic HFOV when using oscillatory waveforms that consisted of either a single discrete frequency or two simultaneous frequencies. We utilized a three-dimensional, anatomically structured canine lung model for simulating frequency-dependent ventilation distribution. Gas transport was simulated via direct alveolar ventilation, advective mixing at bifurcations, turbulent and oscillatory dispersion, and molecular diffusion. Volume amplitudes at each oscillatory frequency were iteratively optimized to attain eucapnia. Ventilation using single-frequency HFOV demonstrated increasing heterogeneity of acinar flow and CO2 elimination with frequency for frequencies greater than the resonant frequency. For certain pairs of frequencies, a linear combination of the two corresponding ventilation distributions yielded reduced acinar strain heterogeneity compared with either frequency alone. Our model demonstrates that superposition of two simultaneous oscillatory frequencies can achieve more uniform ventilation distribution, and therefore lessen the potential for ventilator-induced lung injury, compared with traditional single-frequency HFOV. NEW & NOTEWORTHY In this study, we simulated oscillatory ventilation with multiple simultaneous frequencies using a computational lung model that includes distributed flow and gas transport. A mechanism of benefit was identified by which ventilation with two simultaneous frequencies results in reduced acinar strain heterogeneity compared with either frequency alone. This finding suggests the possibility of tuning the spectral content of ventilator waveforms according to patient-specific mechanical heterogeneity.
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Affiliation(s)
- Jacob Herrmann
- Department of Anesthesia, University of Iowa , Iowa City, Iowa.,Department of Biomedical Engineering, University of Iowa , Iowa City, Iowa
| | - Merryn H Tawhai
- Auckland Bioengineering Institute, University of Auckland , Auckland , New Zealand
| | - David W Kaczka
- Department of Anesthesia, University of Iowa , Iowa City, Iowa.,Department of Biomedical Engineering, University of Iowa , Iowa City, Iowa.,Department of Radiology, University of Iowa , Iowa City, Iowa
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45
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Henderson WR, Chen L, Amato MBP, Brochard LJ. Fifty Years of Research in ARDS. Respiratory Mechanics in Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med 2017; 196:822-833. [PMID: 28306327 DOI: 10.1164/rccm.201612-2495ci] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Acute respiratory distress syndrome is a multifactorial lung injury that continues to be associated with high levels of morbidity and mortality. Mechanical ventilation, although lifesaving, is associated with new iatrogenic injury. Current best practice involves the use of small Vt, low plateau and driving pressures, and high levels of positive end-expiratory pressure. Collectively, these interventions are termed "lung-protective ventilation." Recent investigations suggest that individualized measurements of pulmonary mechanical variables rather than population-based ventilation prescriptions may be used to set the ventilator with the potential to improve outcomes beyond those achieved with standard lung protective ventilation. This review outlines the measurement and application of clinically applicable pulmonary mechanical concepts, such as plateau pressures, driving pressure, transpulmonary pressures, stress index, and measurement of strain. In addition, the concept of the "baby lung" and the utility of dynamic in addition to static measures of pulmonary mechanical variables are discussed.
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Affiliation(s)
- William R Henderson
- 1 Division of Critical Care Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Lu Chen
- 2 Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada.,3 Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada; and
| | - Marcelo B P Amato
- 4 Cardio-Pulmonary Department, Pulmonary Division, Heart Institute (Incor), University of São Paulo, São Paulo, Brazil
| | - Laurent J Brochard
- 2 Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada.,3 Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada; and
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46
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Abstract
The main goals of assessing respiratory system mechanical function are to evaluate the lung function through a variety of methods and to detect early signs of abnormalities that could affect the patient's outcomes. In ventilated patients, it has become increasingly important to recognize whether respiratory function has improved or deteriorated, whether the ventilator settings match the patient's demand, and whether the selection of ventilator parameters follows a lung-protective strategy. Ventilator graphics, esophageal pressure, intra-abdominal pressure, and electric impedance tomography are some of the best-known monitoring tools to obtain measurements and adequately evaluate the respiratory system mechanical function.
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47
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Loring SH, Topulos GP, Hubmayr RD. Transpulmonary Pressure: The Importance of Precise Definitions and Limiting Assumptions. Am J Respir Crit Care Med 2017; 194:1452-1457. [PMID: 27606837 DOI: 10.1164/rccm.201512-2448cp] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Recent studies applying the principles of respiratory mechanics to respiratory disease have used inconsistent and mutually exclusive definitions of the term "transpulmonary pressure." By the traditional definition, transpulmonary pressure is the pressure across the whole lung, including the intrapulmonary airways, (i.e., the pressure difference between the opening to the pulmonary airway and the pleural surface). However, more recently transpulmonary pressure has also been defined as the pressure across only the lung tissue (i.e., the pressure difference between the alveolar space and the pleural surface), traditionally known as the "elastic recoil pressure of the lung." Multiple definitions of the same term, and failure to recognize their underlying assumptions, have led to different interpretations of lung physiology and conclusions about appropriate therapy for patients. It is our view that many current controversies in the physiological interpretation of disease are caused by the lack of consistency in the definitions of these common physiological terms. In this article, we discuss the historical uses of these terms and recent misconceptions that may have resulted when these terms were confused. These misconceptions include assertions that normal pleural pressure must be negative (subatmospheric) and that a pressure in the pleural space may not be substantially positive when a subject is relaxed with an open airway. We urge specificity and uniformity when using physiological terms to define the physical state of the lungs, the chest wall, and the integrated respiratory system.
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Affiliation(s)
- Stephen H Loring
- 1 Department of Anesthesia, Critical Care, and Pain Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts
| | - George P Topulos
- 2 Department of Anesthesia, Perioperative and Pain Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts; and
| | - Rolf D Hubmayr
- 3 Division of Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester, Minnesota
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48
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Grieco DL, Chen L, Brochard L. Transpulmonary pressure: importance and limits. ANNALS OF TRANSLATIONAL MEDICINE 2017; 5:285. [PMID: 28828360 DOI: 10.21037/atm.2017.07.22] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Transpulmonary pressure (PL) is computed as the difference between airway pressure and pleural pressure and separates the pressure delivered to the lung from the one acting on chest wall and abdomen. Pleural pressure is measured as esophageal pressure (PES) through dedicated catheters provided with esophageal balloons. We discuss the role of PL in assessing the effects of mechanical ventilation in patients with acute respiratory distress syndrome (ARDS). In the supine position, directly measured PL represents the pressure acting on the alveoli and airways. Because there is a pressure gradient in the pleural space from the non-dependent to the dependent zones, the pressure in the esophagus probably represents the pressure at a mid-level between sternal and vertebral regions. For this reason, it has been proposed to set the end-expiratory pressure in order to get a positive value of PL. This improves oxygenation and compliance. PL can also be estimated from airway pressure plateau and the ratio of lung to respiratory elastance (elastance-derived method). Some data suggest that this latter calculation may better estimate PL in the nondependent lung zones, at risk for hyperinflation. Elastance-derived PL at end-inspiration (PLend-insp) may be a good surrogate of end-inspiratory lung stress for the "baby lung", at least in non-obese patients. Limiting end-inspiratory PL to 20-25 cmH2O appears physiologically sound to mitigate ventilator-induced lung injury (VILI). Last, lung driving pressure (∆PL) reflects the tidal distending pressure. Changes in PL may also be assessed during assisted breathing to take into account the additive effects of spontaneous breathing and mechanical breaths on lung distension. In summary, despite limitations, assessment of PL allows a deeper understanding of the risk of VILI and may potentially help tailor ventilator settings.
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Affiliation(s)
- Domenico Luca Grieco
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada.,Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St Michael's Hospital, Toronto, Canada.,Department of Anesthesiology and Intensive Care Medicine, Catholic University of the Sacred Heart, "A. Gemelli" University Hospital, Rome, Italy
| | - Lu Chen
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada.,Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St Michael's Hospital, Toronto, Canada
| | - Laurent Brochard
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada.,Keenan Research Centre and Li Ka Shing Institute, Department of Critical Care, St Michael's Hospital, Toronto, Canada
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49
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Bime C, Fiero M, Lu Z, Oren E, Berry CE, Parthasarathy S, Garcia JGN. High Positive End-Expiratory Pressure Is Associated with Improved Survival in Obese Patients with Acute Respiratory Distress Syndrome. Am J Med 2017; 130:207-213. [PMID: 27984004 PMCID: PMC5839112 DOI: 10.1016/j.amjmed.2016.09.029] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 08/24/2016] [Accepted: 09/28/2016] [Indexed: 11/17/2022]
Abstract
BACKGROUND In acute respiratory distress syndrome, minimizing lung injury from repeated collapse and reopening of alveoli by applying a high positive end-expiratory pressure improves oxygenation without influencing mortality. Obesity causes alveolar atelectasis, thus suggesting that a higher positive end-expiratory pressure might be more protective among the obese. We hypothesized that the effect of applying a high positive end-expiratory pressure on mortality from acute respiratory distress syndrome would differ by obesity status. METHODS This was a retrospective analysis of 505 patients from the Assessment of Low tidal Volume and elevated End-expiratory volume to Obviate Lung Injury Trial, a multicenter randomized trial that compared a higher vs a lower positive end-expiratory pressure ventilatory strategy in acute respiratory distress syndrome. We examined the relationship between positive end-expiratory pressure strategy and 60-day mortality stratified by obesity status. RESULTS Among obese patients with acute respiratory distress syndrome, those assigned to a high positive end-expiratory pressure strategy experienced lower mortality compared with those assigned to a low strategy (18% vs 32%; P = .04). Among the nonobese, those assigned to high positive end-expiratory pressure strategy experienced similar mortality with those assigned to low strategy (34% vs 23%; P = .13). Multivariate analysis demonstrated an interaction between obesity status and the effect of positive end-expiratory pressure strategy on mortality (P <.01). CONCLUSIONS Ventilation with higher levels of positive end-expiratory pressure was associated with improved survival among the subgroup of patients with acute respiratory distress syndrome who are obese.
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Affiliation(s)
- Christian Bime
- Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Department of Medicine, University of Arizona College of Medicine, Tucson; University of Arizona Health Sciences, Tucson.
| | - Mallorie Fiero
- Department of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson
| | - Zhenqiang Lu
- University of Arizona Health Sciences, Tucson; BiO5 Institute - The University of Arizona, Tucson
| | - Eyal Oren
- Department of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson
| | - Cristine E Berry
- Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Department of Medicine, University of Arizona College of Medicine, Tucson; University of Arizona Health Sciences, Tucson
| | - Sairam Parthasarathy
- Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Department of Medicine, University of Arizona College of Medicine, Tucson; University of Arizona Health Sciences, Tucson
| | - Joe G N Garcia
- Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Department of Medicine, University of Arizona College of Medicine, Tucson; University of Arizona Health Sciences, Tucson
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50
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Chen H, Yang YL, Xu M, Shi ZH, He X, Sun XM, Luo XY, Chen GQ, Zhou JX. Use of the injection test to indicate the oesophageal balloon position in patients without spontaneous breathing: a clinical feasibility study. J Int Med Res 2017; 45:320-331. [PMID: 28222644 PMCID: PMC5536601 DOI: 10.1177/0300060516679776] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Objective To investigate the clinical feasibility of the injection test for balloon placement during oesophageal pressure measurement in patients without spontaneous breathing. Methods The injection test was performed in 12 mechanically ventilated patients under deep sedation and paralysis. During withdrawal of the balloon from the stomach and air injection into the gastric lumen of the catheter, the presence of the injection test wave in the balloon pressure tracing indicated that the whole balloon was positioned above the lower oesophageal sphincter (LES). The positive pressure occlusion test was performed at different balloon positions. Results In each patient, the injection test wave appeared at a distinct balloon depth, with a mean ± standard deviation of 41.9 ± 3.3 cm and range from 37 cm to 47 cm. The optimal ratio of changes in the balloon and airway pressure (0.8–1.2) during the positive pressure occlusion test was obtained when the balloon was located 5 cm and 10 cm above the LES in nine (75%) and three (25%) patients, respectively. Conclusions The injection test is feasible for identification of the whole balloon position above the LES during passive ventilation. The middle third of the oesophagus might be the optimal balloon position.
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Affiliation(s)
- Han Chen
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,2 Fujian Provincial Clinical College Hospital, Fujian Medical University, Fuzhou, Fujian, China
| | - Yan-Lin Yang
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,3 Beijing Electric Power Hospital, Capital Medical University, Beijing, China
| | - Ming Xu
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Zhong-Hua Shi
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Xuan He
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Xiu-Mei Sun
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Xu-Ying Luo
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Guang-Qiang Chen
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Jian-Xin Zhou
- 1 Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
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