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Songsangvorn N, Xu Y, Lu C, Rotstein O, Brochard L, Slutsky AS, Burns KEA, Zhang H. Electrical impedance tomography-guided positive end-expiratory pressure titration in ARDS: a systematic review and meta-analysis. Intensive Care Med 2024; 50:617-631. [PMID: 38512400 PMCID: PMC11078723 DOI: 10.1007/s00134-024-07362-2] [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: 12/16/2023] [Accepted: 02/14/2024] [Indexed: 03/23/2024]
Abstract
PURPOSE Assessing efficacy of electrical impedance tomography (EIT) in optimizing positive end-expiratory pressure (PEEP) for acute respiratory distress syndrome (ARDS) patients to enhance respiratory system mechanics and prevent ventilator-induced lung injury (VILI), compared to traditional methods. METHODS We carried out a systematic review and meta-analysis, spanning literature from January 2012 to May 2023, sourced from Scopus, PubMed, MEDLINE (Ovid), Cochrane, and LILACS, evaluated EIT-guided PEEP strategies in ARDS versus conventional methods. Thirteen studies (3 randomized, 10 non-randomized) involving 623 ARDS patients were analyzed using random-effects models for primary outcomes (respiratory mechanics and mechanical power) and secondary outcomes (PaO2/FiO2 ratio, mortality, stays in intensive care unit (ICU), ventilator-free days). RESULTS EIT-guided PEEP significantly improved lung compliance (n = 941 cases, mean difference (MD) = 4.33, 95% confidence interval (CI) [2.94, 5.71]), reduced mechanical power (n = 148, MD = - 1.99, 95% CI [- 3.51, - 0.47]), and lowered driving pressure (n = 903, MD = - 1.20, 95% CI [- 2.33, - 0.07]) compared to traditional methods. Sensitivity analysis showed consistent positive effect of EIT-guided PEEP on lung compliance in randomized clinical trials vs. non-randomized studies pooled (MD) = 2.43 (95% CI - 0.39 to 5.26), indicating a trend towards improvement. A reduction in mortality rate (259 patients, relative risk (RR) = 0.64, 95% CI [0.45, 0.91]) was associated with modest improvements in compliance and driving pressure in three studies. CONCLUSIONS EIT facilitates real-time, individualized PEEP adjustments, improving respiratory system mechanics. Integration of EIT as a guiding tool in mechanical ventilation holds potential benefits in preventing ventilator-induced lung injury. Larger-scale studies are essential to validate and optimize EIT's clinical utility in ARDS management.
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Affiliation(s)
- Nickjaree Songsangvorn
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Department of Critical Care Medicine, Bhumibol Adulyadej Hospital, Bangkok, Thailand
| | - Yonghao Xu
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada.
- The State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
| | - Cong Lu
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
| | - Ori Rotstein
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Laurent Brochard
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| | - Arthur S Slutsky
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| | - Karen E A Burns
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| | - Haibo Zhang
- Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, ON, Canada.
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
- Department of Physiology, University of Toronto, Toronto, ON, Canada.
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, ON, Canada.
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2
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Simonte R, Cammarota G, Vetrugno L, De Robertis E, Longhini F, Spadaro S. Advanced Respiratory Monitoring during Extracorporeal Membrane Oxygenation. J Clin Med 2024; 13:2541. [PMID: 38731069 PMCID: PMC11084162 DOI: 10.3390/jcm13092541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 04/16/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024] Open
Abstract
Advanced respiratory monitoring encompasses a diverse range of mini- or noninvasive tools used to evaluate various aspects of respiratory function in patients experiencing acute respiratory failure, including those requiring extracorporeal membrane oxygenation (ECMO) support. Among these techniques, key modalities include esophageal pressure measurement (including derived pressures), lung and respiratory muscle ultrasounds, electrical impedance tomography, the monitoring of diaphragm electrical activity, and assessment of flow index. These tools play a critical role in assessing essential parameters such as lung recruitment and overdistention, lung aeration and morphology, ventilation/perfusion distribution, inspiratory effort, respiratory drive, respiratory muscle contraction, and patient-ventilator synchrony. In contrast to conventional methods, advanced respiratory monitoring offers a deeper understanding of pathological changes in lung aeration caused by underlying diseases. Moreover, it allows for meticulous tracking of responses to therapeutic interventions, aiding in the development of personalized respiratory support strategies aimed at preserving lung function and respiratory muscle integrity. The integration of advanced respiratory monitoring represents a significant advancement in the clinical management of acute respiratory failure. It serves as a cornerstone in scenarios where treatment strategies rely on tailored approaches, empowering clinicians to make informed decisions about intervention selection and adjustment. By enabling real-time assessment and modification of respiratory support, advanced monitoring not only optimizes care for patients with acute respiratory distress syndrome but also contributes to improved outcomes and enhanced patient safety.
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Affiliation(s)
- Rachele Simonte
- Department of Medicine and Surgery, Università degli Studi di Perugia, 06100 Perugia, Italy; (R.S.); (E.D.R.)
| | - Gianmaria Cammarota
- Department of Translational Medicine, Università del Piemonte Orientale, 28100 Novara, Italy;
| | - Luigi Vetrugno
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, 66100 Chieti, Italy;
| | - Edoardo De Robertis
- Department of Medicine and Surgery, Università degli Studi di Perugia, 06100 Perugia, Italy; (R.S.); (E.D.R.)
| | - Federico Longhini
- Department of Medical and Surgical Sciences, Università della Magna Graecia, 88100 Catanzaro, Italy
- Anesthesia and Intensive Care Unit, “R. Dulbecco” University Hospital, 88100 Catanzaro, Italy
| | - Savino Spadaro
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, 44100 Ferrara, Italy;
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3
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Franchineau G, Jonkman AH, Piquilloud L, Yoshida T, Costa E, Rozé H, Camporota L, Piraino T, Spinelli E, Combes A, Alcala GC, Amato M, Mauri T, Frerichs I, Brochard LJ, Schmidt M. Electrical Impedance Tomography to Monitor Hypoxemic Respiratory Failure. Am J Respir Crit Care Med 2024; 209:670-682. [PMID: 38127779 DOI: 10.1164/rccm.202306-1118ci] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Accepted: 12/20/2023] [Indexed: 12/23/2023] Open
Abstract
Hypoxemic respiratory failure is one of the leading causes of mortality in intensive care. Frequent assessment of individual physiological characteristics and delivery of personalized mechanical ventilation (MV) settings is a constant challenge for clinicians caring for these patients. Electrical impedance tomography (EIT) is a radiation-free bedside monitoring device that is able to assess regional lung ventilation and changes in aeration. With real-time tomographic functional images of the lungs obtained through a thoracic belt, clinicians can visualize and estimate the distribution of ventilation at different ventilation settings or following procedures such as prone positioning. Several studies have evaluated the performance of EIT to monitor the effects of different MV settings in patients with acute respiratory distress syndrome, allowing more personalized MV. For instance, EIT could help clinicians find the positive end-expiratory pressure that represents a compromise between recruitment and overdistension and assess the effect of prone positioning on ventilation distribution. The clinical impact of the personalization of MV remains to be explored. Despite inherent limitations such as limited spatial resolution, EIT also offers a unique noninvasive bedside assessment of regional ventilation changes in the ICU. This technology offers the possibility of a continuous, operator-free diagnosis and real-time detection of common problems during MV. This review provides an overview of the functioning of EIT, its main indices, and its performance in monitoring patients with acute respiratory failure. Future perspectives for use in intensive care are also addressed.
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Affiliation(s)
- Guillaume Franchineau
- Service de Medecine Intensive Reanimation, Centre Hospitalier Intercommunal de Poissy-Saint-Germain-en-Laye, Poissy, France
| | - Annemijn H Jonkman
- Department of Intensive Care Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Lise Piquilloud
- Adult Intensive Care Unit, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Takeshi Yoshida
- Department of Anesthesiology and Intensive Care Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Eduardo Costa
- Pulmonary Division, Cardiopulmonary Department, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - Hadrien Rozé
- Department of Thoraco-Abdominal Anesthesiology and Intensive Care, Bordeaux University Hospital, University of Bordeaux, Bordeaux, France
- Réanimation Polyvalente, Centre Hospitalier Côte Basque, Bayonne, France
| | - Luigi Camporota
- Health Centre for Human and Applied Physiological Sciences, Department of Adult Critical Care, Guy's and St Thomas' National Health Service Foundation Trust, London, United Kingdom
| | - Thomas Piraino
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, Unity Health Toronto, Toronto, Ontario, Canada
- Division of Critical Care, Department of Anesthesia, McMaster University, Hamilton, Ontario, Canada
| | - Elena Spinelli
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alain Combes
- Sorbonne Université, Groupe de Recherche Clinique 30, Réanimation et Soins Intensifs du Patient en Insuffisance Respiratoire Aigüe, UMRS_1166-ICAN, Institute of Cardiometabolism and Nutrition, Service de Médecine Intensive - Réanimation, Assistance Publique-Hôpitaux de Paris (APHP) Hôpital Pitié-Salpêtrière, Paris, France
| | - Glasiele C Alcala
- Pulmonary Division, Cardiopulmonary Department, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - Marcelo Amato
- Pulmonary Division, Cardiopulmonary Department, Heart Institute, University of São Paulo, São Paulo, Brazil
| | - Tommaso Mauri
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplants, University of Milan, Milan, Italy
| | - Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Centre of Schleswig-Holstein Campus Kiel, Kiel, Germany; and
| | - Laurent J Brochard
- Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, Unity Health Toronto, Toronto, Ontario, Canada
- Interdepartmental Division of Critical Care, University of Toronto, Toronto, Ontario, Canada
| | - Matthieu Schmidt
- Sorbonne Université, Groupe de Recherche Clinique 30, Réanimation et Soins Intensifs du Patient en Insuffisance Respiratoire Aigüe, UMRS_1166-ICAN, Institute of Cardiometabolism and Nutrition, Service de Médecine Intensive - Réanimation, Assistance Publique-Hôpitaux de Paris (APHP) Hôpital Pitié-Salpêtrière, Paris, France
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4
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Plens GM, Droghi MT, Alcala GC, Pereira SM, Wawrzeniak IC, Victorino JA, Crivellari C, Grassi A, Rezoagli E, Foti G, Costa ELV, Amato MBP, Bellani G. Expiratory Muscle Activity Counteracts Positive End-Expiratory Pressure and Is Associated with Fentanyl Dose in Patients with Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med 2024; 209:563-572. [PMID: 38190718 DOI: 10.1164/rccm.202308-1376oc] [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: 08/07/2023] [Accepted: 01/02/2024] [Indexed: 01/10/2024] Open
Abstract
Rationale: Hypoxemia during mechanical ventilation might be worsened by expiratory muscle activity, which reduces end-expiratory lung volume through lung collapse. A proposed mechanism of benefit of neuromuscular blockade in acute respiratory distress syndrome (ARDS) is the abolition of expiratory efforts. This may contribute to the restoration of lung volumes. The prevalence of this phenomenon, however, is unknown. Objectives: To investigate the incidence and amount of end-expiratory lung impedance (EELI) increase after the administration of neuromuscular blocking agents (NMBAs), clinical factors associated with this phenomenon, its impact on regional lung ventilation, and any association with changes in pleural pressure. Methods: We included mechanically ventilated patients with ARDS monitored with electrical impedance tomography (EIT) who received NMBAs in one of two centers. We measured changes in EELI, a surrogate for end-expiratory lung volume, before and after NMBA administration. In an additional 10 patients, we investigated the characteristic signatures of expiratory muscle activity depicted by EIT and esophageal catheters simultaneously. Clinical factors associated with EELI changes were assessed. Measurements and Main Results: We included 46 patients, half of whom showed an increase in EELI of >10% of the corresponding Vt (46.2%; IQR, 23.9-60.9%). The degree of EELI increase correlated positively with fentanyl dosage and negatively with changes in end-expiratory pleural pressures. This suggests that expiratory muscle activity might exert strong counter-effects against positive end-expiratory pressure that are possibly aggravated by fentanyl. Conclusions: Administration of NMBAs during EIT monitoring revealed activity of expiratory muscles in half of patients with ARDS. The resultant increase in EELI had a dose-response relationship with fentanyl dosage. This suggests a potential side effect of fentanyl during protective ventilation.
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Affiliation(s)
- Glauco M Plens
- Laboratório de Pneumologia LIM-09, Disciplina de Pneumologia, Heart Institute (Incor), Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo, São Paulo, Brazil
| | - Maddalena T Droghi
- Department of Emergency and Intensive Care, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico San Gerardo dei Tintori, Monza, Italy
| | - Glasiele C Alcala
- Laboratório de Pneumologia LIM-09, Disciplina de Pneumologia, Heart Institute (Incor), Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo, São Paulo, Brazil
| | - Sérgio M Pereira
- Department of Anesthesia, St Michael's Hospital, Toronto, Ontario, Canada
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Iuri C Wawrzeniak
- Programa de Pós-Graduação em Ciências Médicas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Intensive Care Unit, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Josué A Victorino
- Intensive Care Unit, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
- Internal Medicine Department, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
| | - Chiara Crivellari
- School of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | - Alice Grassi
- School of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | - Emanuele Rezoagli
- Department of Emergency and Intensive Care, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico San Gerardo dei Tintori, Monza, Italy
- School of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | - Giuseppe Foti
- Department of Emergency and Intensive Care, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico San Gerardo dei Tintori, Monza, Italy
- School of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | - Eduardo L V Costa
- Laboratório de Pneumologia LIM-09, Disciplina de Pneumologia, Heart Institute (Incor), Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo, São Paulo, Brazil
- Research and Education Institute, Hospital Sírio-Libanes, Sao Paulo, Brazil
| | - Marcelo B P Amato
- Laboratório de Pneumologia LIM-09, Disciplina de Pneumologia, Heart Institute (Incor), Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo, São Paulo, Brazil
| | - Giacomo Bellani
- Centre for Medical Sciences-CISMed, University of Trento, Trento, Italy; and
- Department of Anesthesia and Intensive Care, Santa Chiara Regional Hospital, Azienda Provinciale per i Servizi Sanitari Trento, Trento, Italy
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5
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Frerichs I, Schädler D, Becher T. Setting positive end-expiratory pressure by using electrical impedance tomography. Curr Opin Crit Care 2024; 30:43-52. [PMID: 38085866 DOI: 10.1097/mcc.0000000000001117] [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 This review presents the principles and possibilities of setting positive end-expiratory pressure (PEEP) using electrical impedance tomography (EIT). It summarizes the major findings of recent studies where EIT was applied to monitor the effects of PEEP on regional lung function and to guide the selection of individualized PEEP setting. RECENT FINDINGS The most frequent approach of utilizing EIT for the assessment of PEEP effects and the PEEP setting during the time period from January 2022 till June 2023 was based on the analysis of pixel tidal impedance variation, typically acquired during stepwise incremental and/or decremental PEEP variation. The most common EIT parameters were the fraction of ventilation in various regions of interest, global inhomogeneity index, center of ventilation, silent spaces, and regional compliance of the respiratory system. The studies focused mainly on the spatial and less on the temporal distribution of ventilation. Contrast-enhanced EIT was applied in a few studies for the estimation of ventilation/perfusion matching. SUMMARY The availability of commercial EIT devices resulted in an increase in clinical studies using this bedside imaging technology in neonatal, pediatric and adult critically ill patients. The clinical interest in EIT became evident but the potential of this method in clinical decision-making still needs to be fully exploited.
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Affiliation(s)
- Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
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6
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Esposito T, Fregonese M, Morettini G, Carboni P, Tardioli C, Messina A, Vaschetto R, Della Corte F, Vetrugno L, Navalesi P, De Robertis E, Azzolina D, Piriyapatsom A, Tucci MR, Wrigge H, Simon P, Bignami E, Maggiore SM, Simonte R, Cammarota G. Intraoperative individualization of positive-end-expiratory pressure through electrical impedance tomography or esophageal pressure assessment: a systematic review and meta-analysis of randomized controlled trials. J Clin Monit Comput 2024; 38:89-100. [PMID: 37863862 DOI: 10.1007/s10877-023-01094-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 10/09/2023] [Indexed: 10/22/2023]
Abstract
PURPOSE This systematic review of randomized-controlled trials (RCTs) with meta-analyses aimed to compare the effects on intraoperative arterial oxygen tension to inspired oxygen fraction ratio (PaO2/FiO2), exerted by positive end-expiratory pressure (PEEP) individualized trough electrical impedance tomography (EIT) or esophageal pressure (Pes) assessment (intervention) vs. PEEP not tailored on EIT or Pes (control), in patients undergoing abdominal or pelvic surgery with an open or laparoscopic/robotic approach. METHODS PUBMED®, EMBASE®, and Cochrane Controlled Clinical trials register were searched for observational studies and RCTs from inception to the end of August 2022. Inclusion criteria were: RCTs comparing PEEP titrated on EIT/Pes assessment vs. PEEP not individualized on EIT/Pes and reporting intraoperative PaO2/FiO2. Two authors independently extracted data from the enrolled investigations. Data are reported as mean difference and 95% confidence interval (CI). RESULTS Six RCTs were included for a total of 240 patients undergoing general anesthesia for surgery, of whom 117 subjects in the intervention group and 123 subjects in the control group. The intraoperative mean PaO2/FiO2 was 69.6 (95%CI 32.-106.4 ) mmHg higher in the intervention group as compared with the control group with 81.4% between-study heterogeneity (p < 0.01). However, at meta-regression, the between-study heterogeneity diminished to 44.96% when data were moderated for body mass index (estimate 3.45, 95%CI 0.78-6.11, p = 0.011). CONCLUSIONS In patients undergoing abdominal or pelvic surgery with an open or laparoscopic/robotic approach, PEEP personalized by EIT or Pes allowed the achievement of a better intraoperative oxygenation compared to PEEP not individualized through EIT or Pes. PROSPERO REGISTRATION NUMBER CRD 42021218306, 30/01/2023.
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Affiliation(s)
- Teresa Esposito
- Department of Anesthesiology and Intensive Care, 'Maggiore della Carità' Hospital, Novara, Italy
| | - Martina Fregonese
- Department of Medicine and Surgery, Università degli Studi di Perugia, Perugia, Italy
| | - Giulio Morettini
- Department of Medicine and Surgery, Università degli Studi di Perugia, Perugia, Italy
| | - Paloma Carboni
- Department of Medicine and Surgery, Università degli Studi di Perugia, Perugia, Italy
| | - Cecilia Tardioli
- Department of Medicine and Surgery, Università degli Studi di Perugia, Perugia, Italy
| | - Antonio Messina
- Humanitas Clinical and Research Center-IRCCS, Rozzano, Italy
| | - Rosanna Vaschetto
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Francesco Della Corte
- Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy
| | - Luigi Vetrugno
- Department of Medical, Oral and Biotechnological Sciences, Università Gabriele D'Annunzio di Chieti-Pescara, Chieti, Italy
| | - Paolo Navalesi
- Department of Medicine, Università degli Studi Di Padova, Padova, Italy
| | - Edoardo De Robertis
- Department of Medicine and Surgery, Università degli Studi di Perugia, Perugia, Italy
| | - Danila Azzolina
- Department of Ambiental Science and Prevention, Università degli Studi di Ferrara, Ferrara, Italy
| | - Annop Piriyapatsom
- Department of Anesthesiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Mauro R Tucci
- Service of Pneumology, Instituto do Coracao, Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Hermann Wrigge
- Integrated Research and Treatment Centre Adiposity Diseases, University of Leipzig, Leipzig, Germany
- Department of Anesthesiology, Intensive Care and Emergency Medicine, Pain Therapy, Bergmannstrost Hospital, Halle, Germany
- Medical Faculty, Martin-Luther University Halle-Wittenberg, Halle, Germany
| | - Philipp Simon
- Integrated Research and Treatment Centre Adiposity Diseases, University of Leipzig, Leipzig, Germany
- Anesthesiology and Operative Intensive Care, Faculty of Medicine, University of Augsburg, Augsburg, Germany
| | - Elena Bignami
- Anesthesiology, Critical Care and Pain Medicine Division, Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - 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
| | - Rachele Simonte
- Department of Anesthesiology and Intensive Care, 'Maggiore della Carità' Hospital, Novara, Italy
| | - Gianmaria Cammarota
- Department of Medicine and Surgery, Università degli Studi di Perugia, Perugia, Italy.
- Dipartimento di Medicina Traslazionale, Università degli Studi del Piemonte Orientale, Novara, Italy.
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Jacquier M, Labruyère M, Ecarnot F, Roudaut JB, Andreu P, Voizeux P, Save Q, Pedri R, Rigaud JP, Quenot JP. Ventilatory Management of Patients with Acute Respiratory Distress Syndrome Due to SARS-CoV-2. J Clin Med 2023; 12:7509. [PMID: 38137578 PMCID: PMC10743400 DOI: 10.3390/jcm12247509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 11/20/2023] [Accepted: 11/29/2023] [Indexed: 12/24/2023] Open
Abstract
The emergence of the new SARS-CoV-2 in December 2019 caused a worldwide pandemic of the resultant disease, COVID-19. There was a massive surge in admissions to intensive care units (ICU), notably of patients with hypoxaemic acute respiratory failure. In these patients, optimal oxygen therapy was crucial. In this article, we discuss tracheal intubation to provide mechanical ventilation in patients with hypoxaemic acute respiratory failure due to SARS-CoV-2. We first describe the pathophysiology of respiratory anomalies leading to acute respiratory distress syndrome (ARDS) due to infection with SARS-CoV-2, and then briefly review management, focusing particularly on the ventilation strategy. Overall, the ventilatory management of ARDS due to SARS-CoV-2 infection is largely the same as that applied in ARDS from other causes, and lung-protective ventilation is recommended. The difference lies in the initial clinical presentation, with profound hypoxaemia often observed concomitantly with near-normal pulmonary compliance.
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Affiliation(s)
- Marine Jacquier
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
- Lipness Team, INSERM Research Centre LNC-UMR1231 and LabEx LipSTIC, University of Burgundy, 21000 Dijon, France
| | - Marie Labruyère
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
- INSERM CIC 1432, Clinical Epidemiology, University of Burgundy, 21000 Dijon, France
| | - Fiona Ecarnot
- Department of Cardiology, University Hospital Besancon, 25030 Besançon, France;
- EA3920, University of Franche-Comté, 25000 Besançon, France
| | - Jean-Baptiste Roudaut
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
| | - Pascal Andreu
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
| | - Pierre Voizeux
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
| | - Quentin Save
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
| | - Romain Pedri
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
| | - Jean-Philippe Rigaud
- Department of Intensive Care, Centre Hospitalier de Dieppe, 76202 Dieppe, France;
- Espace de Réflexion Éthique de Normandie, University Hospital Caen, 14000 Caen, France
| | - Jean-Pierre Quenot
- Department of Intensive Care, François Mitterrand, University Hospital, 21000 Dijon, France; (M.J.); (M.L.); (J.-B.R.); (P.A.); (P.V.); (Q.S.); (R.P.)
- Lipness Team, INSERM Research Centre LNC-UMR1231 and LabEx LipSTIC, University of Burgundy, 21000 Dijon, France
- INSERM CIC 1432, Clinical Epidemiology, University of Burgundy, 21000 Dijon, France
- DRCI, USMR, CHU Dijon Bourgogne, 21000 Dijon, France
- Espace de Réflexion Éthique Bourgogne Franche-Comté (EREBFC), University of Burgundy, 21000 Dijon, France
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8
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Heines SJH, Becher TH, van der Horst ICC, Bergmans DCJJ. Clinical Applicability of Electrical Impedance Tomography in Patient-Tailored Ventilation: A Narrative Review. Tomography 2023; 9:1903-1932. [PMID: 37888742 PMCID: PMC10611090 DOI: 10.3390/tomography9050150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 10/05/2023] [Accepted: 10/16/2023] [Indexed: 10/28/2023] Open
Abstract
Electrical Impedance Tomography (EIT) is a non-invasive bedside imaging technique that provides real-time lung ventilation information on critically ill patients. EIT can potentially become a valuable tool for optimising mechanical ventilation, especially in patients with acute respiratory distress syndrome (ARDS). In addition, EIT has been shown to improve the understanding of ventilation distribution and lung aeration, which can help tailor ventilatory strategies according to patient needs. Evidence from critically ill patients shows that EIT can reduce the duration of mechanical ventilation and prevent lung injury due to overdistension or collapse. EIT can also identify the presence of lung collapse or recruitment during a recruitment manoeuvre, which may guide further therapy. Despite its potential benefits, EIT has not yet been widely used in clinical practice. This may, in part, be due to the challenges associated with its implementation, including the need for specialised equipment and trained personnel and further validation of its usefulness in clinical settings. Nevertheless, ongoing research focuses on improving mechanical ventilation and clinical outcomes in critically ill patients.
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Affiliation(s)
- Serge J. H. Heines
- Department of Intensive Care Medicine, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands; (I.C.C.v.d.H.); (D.C.J.J.B.)
| | - Tobias H. Becher
- Department of Anesthesiology and Intensive Care Medicine, Campus Kiel, University Medical Centre Schleswig-Holstein, 24118 Kiel, Germany;
| | - Iwan C. C. van der Horst
- Department of Intensive Care Medicine, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands; (I.C.C.v.d.H.); (D.C.J.J.B.)
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 HX Maastricht, The Netherlands
| | - Dennis C. J. J. Bergmans
- Department of Intensive Care Medicine, Maastricht University Medical Centre+, 6229 HX Maastricht, The Netherlands; (I.C.C.v.d.H.); (D.C.J.J.B.)
- School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, 6229 ER Maastricht, The Netherlands
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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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Brunelle T, Prud'homme E, Alphonsine JE, Baumstarck K, Sanz C, Salmi S, Peres N, Forel JM, Papazian L, Hraiech S, Roch A, Guervilly C. Awake prone position in COVID-19 acute respiratory failure: a randomized crossover study using electrical impedance tomography. ERJ Open Res 2023; 9:00509-2022. [PMID: 36994452 PMCID: PMC9922472 DOI: 10.1183/23120541.00509-2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 12/08/2022] [Indexed: 02/05/2023] Open
Abstract
BackgroundThe goal of this study was to determine whether an awake prone position (aPP) reduces the global inhomogeneity (GI) index of ventilation measured by electrical impedance tomography (EIT) in COVID-19 patients with acute respiratory failure (ARF).MethodsThis prospective crossover study included COVID-19 patients with COVID-19 and ARF defined by PaO2:FiO2of 100–300 mmHg. After baseline evaluation and 30 min EIT recording in the supine position (SP), patients were randomized into one of two sequences: SP-aPP or aPP-SP. At the end of each 2 h step, oxygenation, respiratory rate, Borg scale, and 30 min EIT were recorded.ResultsTen patients were randomized in each group. The GI index did not change in the SP-aPP group (baseline 74±20%, end of SP 78±23% and end of aPP 72±20%, p=0.85) or in the aPP-SP group (baseline 59±14%, end of aPP 59±15% and end of SP 54±13%, p=0.67). In the whole cohort, PaO2:FiO2increased from 133±44 mmHg at baseline to 183±66 mmHg in aPP (p=0.003) and decreased to 129±49 mmHg in SP (p=0.03).ConclusionIn spontaneously breathing non-intubated COVID-19 patients with acute respiratory failure, aPP was not associated with a decrease of lung ventilation inhomogeneity assessed by EIT, despite an improvement in oxygenation.
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11
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Liu W, Yu K, Xiao L, Gao D, Liu X, Cao Y, Lin X, Liu L, Miao H, Li T. Effects of Electrical Impedance Tomography-Guided Positive End-Expiratory Pressure on Postoperative Cardiopulmonary Exercise Capacity in Elderly Patients: Study Protocol for a Randomized Controlled Trial. Med Sci Monit 2023; 29:e938333. [PMID: 36617749 PMCID: PMC9838052 DOI: 10.12659/msm.938333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Mechanical ventilation can lead to cardiopulmonary complications in elderly patients undergoing abdominal surgery plus general anesthesia. The cardiopulmonary exercise test (CPET) is a dynamic and noninvasive evaluation method for assessing the cardiopulmonary system function under rest and stress. Positive end-expiratory pressure (PEEP) titration guided by electrical impedance tomography (EIT) can individualize lung protection strategies and may be beneficial in postoperative cardiopulmonary exercise capacity for these patients. MATERIAL AND METHODS This study is a prospective, single-center, randomized, and controlled trail that will include 80 elderly patients scheduled for major abdominal surgery. The patients will be divided into 2 groups: (1) intervention group: using individualized PEEP ventilation; and (2) control group: using fixed PEEP ventilation (3-5 cmH₂O). RESULTS The primary outcome is the change of postoperative cardiopulmonary exercise capacity. CONCLUSIONS In this study, we will evaluate if EIT-guided PEEP titration can improve postoperative cardiopulmonary exercise capacity and reduce postoperative complications in elderly patients undergoing open abdominal surgery plus general anesthesia. If the result is in accordance with the hypothesis, it would provide evidence to aid the perioperative management for these patients.
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Affiliation(s)
- Wentao Liu
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Kang Yu
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Li Xiao
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Danyang Gao
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Xiao Liu
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Ying Cao
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Xiaowan Lin
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Lei Liu
- Department of Science and Technology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Huihui Miao
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
| | - Tianzuo Li
- Department of Anesthesiology, Beijing Shijitan Hospital, Capital Medical University, Beijing, PR China
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12
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Bajon F, Gauthier V. Management of refractory hypoxemia using recruitment maneuvers and rescue therapies: A comprehensive review. Front Vet Sci 2023; 10:1157026. [PMID: 37065238 PMCID: PMC10098094 DOI: 10.3389/fvets.2023.1157026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/14/2023] [Indexed: 04/18/2023] Open
Abstract
Refractory hypoxemia in patients with acute respiratory distress syndrome treated with mechanical ventilation is one of the most challenging conditions in human and veterinary intensive care units. When a conventional lung protective approach fails to restore adequate oxygenation to the patient, the use of recruitment maneuvers and positive end-expiratory pressure to maximize alveolar recruitment, improve gas exchange and respiratory mechanics, while reducing the risk of ventilator-induced lung injury has been suggested in people as the open lung approach. Although the proposed physiological rationale of opening and keeping open previously collapsed or obstructed airways is sound, the technique for doing so, as well as the potential benefits regarding patient outcome are highly controversial in light of recent randomized controlled trials. Moreover, a variety of alternative therapies that provide even less robust evidence have been investigated, including prone positioning, neuromuscular blockade, inhaled pulmonary vasodilators, extracorporeal membrane oxygenation, and unconventional ventilatory modes such as airway pressure release ventilation. With the exception of prone positioning, these modalities are limited by their own balance of risks and benefits, which can be significantly influenced by the practitioner's experience. This review explores the rationale, evidence, advantages and disadvantages of each of these therapies as well as available methods to identify suitable candidates for recruitment maneuvers, with a summary on their application in veterinary medicine. Undoubtedly, the heterogeneous and evolving nature of acute respiratory distress syndrome and individual lung phenotypes call for a personalized approach using new non-invasive bedside assessment tools, such as electrical impedance tomography, lung ultrasound, and the recruitment-to-inflation ratio to assess lung recruitability. Data available in human medicine provide valuable insights that could, and should, be used to improve the management of veterinary patients with severe respiratory failure with respect to their intrinsic anatomy and physiology.
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13
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Zhang T, Tian X, Liu X, Ye J, Fu F, Shi X, Liu R, Xu C. Advances of deep learning in electrical impedance tomography image reconstruction. Front Bioeng Biotechnol 2022; 10:1019531. [PMID: 36588934 PMCID: PMC9794741 DOI: 10.3389/fbioe.2022.1019531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 12/02/2022] [Indexed: 12/15/2022] Open
Abstract
Electrical impedance tomography (EIT) has been widely used in biomedical research because of its advantages of real-time imaging and nature of being non-invasive and radiation-free. Additionally, it can reconstruct the distribution or changes in electrical properties in the sensing area. Recently, with the significant advancements in the use of deep learning in intelligent medical imaging, EIT image reconstruction based on deep learning has received considerable attention. This study introduces the basic principles of EIT and summarizes the application progress of deep learning in EIT image reconstruction with regards to three aspects: a single network reconstruction, deep learning combined with traditional algorithm reconstruction, and multiple network hybrid reconstruction. In future, optimizing the datasets may be the main challenge in applying deep learning for EIT image reconstruction. Adopting a better network structure, focusing on the joint reconstruction of EIT and traditional algorithms, and using multimodal deep learning-based EIT may be the solution to existing problems. In general, deep learning offers a fresh approach for improving the performance of EIT image reconstruction and could be the foundation for building an intelligent integrated EIT diagnostic system in the future.
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Affiliation(s)
- Tao Zhang
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China,Drug and Instrument Supervision and Inspection Station, Xining Joint Logistics Support Center, Lanzhou, China
| | - Xiang Tian
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China
| | - XueChao Liu
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China
| | - JianAn Ye
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China
| | - Feng Fu
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China
| | - XueTao Shi
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China
| | - RuiGang Liu
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China
| | - CanHua Xu
- Department of Biomedical Engineering, The Fourth Military Medical University, Xi’an, China,Shaanxi Key Laboratory for Bioelectromagnetic Detection and Intelligent Perception, Xi’an, China,*Correspondence: CanHua Xu,
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14
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Nakayama R, Bunya N, Katayama S, Goto Y, Iwamoto Y, Wada K, Ogura K, Yama N, Takatsuka S, Kishimoto M, Takahashi K, Kakizaki R, Sawamoto K, Uemura S, Harada K, Narimatsu E. Correlation between the hysteresis of the pressure–volume curve and the recruitment-to-inflation ratio in patients with coronavirus disease 2019. Ann Intensive Care 2022; 12:106. [PMID: 36370227 PMCID: PMC9652597 DOI: 10.1186/s13613-022-01081-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 11/02/2022] [Indexed: 11/15/2022] Open
Abstract
Background Since the response to lung recruitment varies greatly among patients receiving mechanical ventilation, lung recruitability should be assessed before recruitment maneuvers. The pressure–volume curve (PV curve) and recruitment-to-inflation ratio (R/I ratio) can be used bedside for evaluating lung recruitability and individualing positive end-expiratory pressure (PEEP). Lung tissue recruitment on computed tomography has been correlated with normalized maximal distance (NMD) of the quasi-static PV curve. NMD is the maximal distance between the inspiratory and expiratory limb of the PV curve normalized to the maximal volume. However, the relationship between the different parameters of hysteresis of the quasi-static PV curve and R/I ratio for recruitability is unknown. Methods We analyzed the data of 33 patients with severe coronavirus disease 2019 (COVID-19) who received invasive mechanical ventilation. Respiratory waveform data were collected from the ventilator using proprietary acquisition software. We examined the relationship of the R/I ratio, quasi-static PV curve items such as NMD, and respiratory system compliance (Crs). Results The median R/I ratio was 0.90 [interquartile range (IQR), 0.70–1.15] and median NMD was 41.0 [IQR, 37.1–44.1]. The NMD correlated significantly with the R/I ratio (rho = 0.74, P < 0.001). Sub-analysis showed that the NMD and R/I ratio did not correlate with Crs at lower PEEP (− 0.057, P = 0.75; and rho = 0.15, P = 0.41, respectively). On the contrary, the ratio of Crs at higher PEEP to Crs at lower PEEP (Crs ratio (higher/lower)) moderately correlated with NMD and R/I ratio (rho = 0.64, P < 0.001; and rho = 0.67, P < 0.001, respectively). Conclusions NMD of the quasi-static PV curve and R/I ratio for recruitability assessment are highly correlated. In addition, NMD and R/I ratio correlated with the Crs ratio (higher/lower). Therefore, NMD and R/I ratio could be potential indicators of recruitability that can be performed at the bedside. Supplementary Information The online version contains supplementary material available at 10.1186/s13613-022-01081-x.
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15
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Liu X, Liu X, Meng J, Liu D, Huang Y, Sang L, Xu Y, Xu Z, He W, Chen S, Zhang R, Liu X, Li Y. Electrical impedance tomography for titration of positive end-expiratory pressure in acute respiratory distress syndrome patients with chronic obstructive pulmonary disease. Crit Care 2022; 26:339. [PMCID: PMC9635124 DOI: 10.1186/s13054-022-04201-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
Background Chronic obstructive pulmonary disease (COPD) is one of most common comorbidities in acute respiratory distress syndrome (ARDS). There are few specific studies on the appropriate ventilation strategy for patients with ARDS comorbid with COPD, especially regarding on positive end-expiratory pressure (PEEP) titration. Methods To compare the respiratory mechanics in mechanical ventilated ARDS patients with or without COPD and to determine whether titration of PEEP based on electrical impedance tomography (EIT) is superior to the ARDSnet protocol. This is a single center, perspective, repeated measure study. ARDS patients requiring mechanical ventilation who were admitted to the intensive care unit between August 2017 and December 2020 were included. ARDS patients were divided according to whether they had COPD into a COPD group and a non-COPD group. Respiratory mechanics, gas exchange, and hemodynamics during ventilation were compared between the groups according to whether the PEEP level was titrated by EIT or the ARDSnet protocol. Results A total of twenty-seven ARDS patients including 14 comorbid with and 13 without COPD who met the study eligibility criteria were recruited. The PEEP levels titrated by EIT and the ARDSnet protocol were lower in the COPD group than in the non-COPD group (6.93 ± 1.69 cm H2O vs. 12.15 ± 2.40 cm H2O, P < 0.001 and 10.43 ± 1.20 cm H2O vs. 14.0 ± 3.0 cm H2O, P < 0.001, respectively). In the COPD group, the PEEP level titrated by EIT was lower than that titrated by the ARDSnet protocol (6.93 ± 1.69 cm H2O vs. 10.43 ± 1.20 cm H2O, P < 0.001), as was the global inhomogeneity (GI) index (0.397 ± 0.040 vs. 0.446 ± 0.052, P = 0.001), plateau airway pressure (16.50 ± 4.35 cm H2O vs. 20.93 ± 5.37 cm H2O, P = 0.001), dead space ventilation ratio (48.29 ± 6.78% vs. 55.14 ± 8.85%, P < 0.001), ventilation ratio (1.63 ± 0.33 vs. 1.87 ± 0.33, P < 0.001), and mechanical power (13.92 ± 2.18 J/min vs. 15.87 ± 2.53 J/min, P < 0.001). The cardiac index was higher when PEEP was treated by EIT than when it was titrated by the ARDSnet protocol (3.41 ± 0.50 L/min/m2 vs. 3.02 ± 0.43 L/min/m2, P < 0.001), as was oxygen delivery (466.40 ± 71.08 mL/min/m2 vs. 411.10 ± 69.71 mL/min/m2, P = 0.001). Conclusion Titrated PEEP levels were lower in patients with ARDS with COPD than in ARDS patients without COPD. In ARDS patient comorbid with COPD, application of PEEP titrated by EIT was lower than those titrated by the ARDSnet protocol, which contributed to improvements in the ventilation ratio, mechanical energy, cardiac index, and oxygen delivery with less of an adverse impact on hemodynamics. Supplementary Information The online version contains supplementary material available at 10.1186/s13054-022-04201-y.
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Affiliation(s)
- Xuesong Liu
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Xiao Liu
- Department of Critical Care Medicine, Huadu District People’s Hospital, Guangzhou, 510800 China
| | - Jue Meng
- grid.79703.3a0000 0004 1764 3838Department of Respiratory Medicine, Nanhai District People’s Hospital and Sixth Affiliated Hospital of South China University of Technology, Foshan, 528200 Guangdong China
| | - Dongdong Liu
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Yongbo Huang
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Ling Sang
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Yonghao Xu
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Zhiheng Xu
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Weiqun He
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Sibei Chen
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Rong Zhang
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Xiaoqing Liu
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
| | - Yimin Li
- grid.470124.4State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Street West, Guangzhou, 510120 Guangdong China
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Jiang H, Han Y, Zheng X, Fang Q. Roles of electrical impedance tomography in lung transplantation. Front Physiol 2022; 13:986422. [PMID: 36407002 PMCID: PMC9669435 DOI: 10.3389/fphys.2022.986422] [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: 07/05/2022] [Accepted: 10/25/2022] [Indexed: 11/06/2022] Open
Abstract
Lung transplantation is the preferred treatment method for patients with end-stage pulmonary disease. However, several factors hinder the progress of lung transplantation, including donor shortages, candidate selection, and various postoperative complications. Electrical impedance tomography (EIT) is a functional imaging tool that can be used to evaluate pulmonary ventilation and perfusion at the bedside. Among patients after lung transplantation, monitoring the graft’s pulmonary function is one of the most concerning issues. The feasible application of EIT in lung transplantation has been reported over the past few years, and this technique has gained increasing interest from multidisciplinary researchers. Nevertheless, physicians still lack knowledge concerning the potential applications of EIT in lung transplantation. We present an updated review of EIT in lung transplantation donors and recipients over the past few years, and discuss the potential use of ventilation- and perfusion-monitoring-based EIT in lung transplantation.
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Affiliation(s)
| | | | - Xia Zheng
- *Correspondence: Xia Zheng, ; Qiang Fang,
| | - Qiang Fang
- *Correspondence: Xia Zheng, ; Qiang Fang,
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17
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Wu XZ, Xia HM, Zhang P, Li L, Hu QH, Guo SP, Li TY. Effects of ultrasound-guided alveolar recruitment manoeuvres compared with sustained inflation or no recruitment manoeuvres on atelectasis in laparoscopic gynaecological surgery as assessed by ultrasonography: a randomized clinical trial. BMC Anesthesiol 2022; 22:261. [PMID: 35974310 PMCID: PMC9380300 DOI: 10.1186/s12871-022-01798-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/03/2022] [Indexed: 12/16/2022] Open
Abstract
Background The majority of patients may experience atelectasis under general anesthesia, and the Trendelenburg position and pneumoperitoneum can aggravate atelectasis during laparoscopic surgery, which promotes postoperative pulmonary complications. Lung recruitment manoeuvres have been proven to reduce perioperative atelectasis, but it remains controversial which method is optimal. Ultrasonic imaging can be conducive to confirming the effect of lung recruitment manoeuvres. The purpose of our study was to assess the effects of ultrasound-guided alveolar recruitment manoeuvres by ultrasonography on reducing perioperative atelectasis and to check whether the effects of recruitment manoeuvres under ultrasound guidance (visual and semiquantitative) on atelectasis are superior to sustained inflation recruitment manoeuvres (classical and widely used) in laparoscopic gynaecological surgery. Methods In this randomized, controlled, double-blinded study, women undergoing laparoscopic gynecological surgery were enrolled. Patients were randomly assigned to receive either lung ultrasound-guided alveolar recruitment manoeuvres (UD group), sustained inflation alveolar recruitment manoeuvres (SI group), or no RMs (C group) using a computer-generated table of random numbers. Lung ultrasonography was performed at four predefined time points. The primary outcome was the difference in lung ultrasound score (LUS) among groups at the end of surgery. Results Lung ultrasound scores in the UD group were significantly lower than those in both the SI group and the C group immediately after the end of surgery (7.67 ± 1.15 versus 9.70 ± 102, difference, -2.03 [95% confidence interval, -2.77 to -1.29], P < 0.001; 7.67 ± 1.15 versus 11.73 ± 1.96, difference, -4.07 [95% confidence interval, -4.81 to -3.33], P < 0.001;, respectively). The intergroup differences were sustained until 30 min after tracheal extubation (9.33 ± 0.96 versus 11.13 ± 0.97, difference, -1.80 [95% confidence interval, -2.42 to -1.18], P < 0.001; 9.33 ± 0.96 versus 10.77 ± 1.57, difference, -1.43 [95% confidence interval, -2.05 to -0.82], P < 0.001;, respectively). The SI group had a significantly lower LUS than the C group at the end of surgery (9.70 ± 1.02 versus 11.73 ± 1.96, difference, -2.03 [95% confidence interval, -2.77 to -1.29] P < 0.001), but the benefit did not persist 30 min after tracheal extubation. Conclusions During general anesthesia, ultrasound-guided recruitment manoeuvres can reduce perioperative aeration loss and improve oxygenation. Furthermore, these effects of ultrasound-guided recruitment manoeuvres on atelectasis are superior to sustained inflation recruitment manoeuvres. Trial registration Chictr.org.cn, ChiCTR2100042731, Registered 27 January 2021, www.chictr.org.cn.
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Affiliation(s)
- Xiong-Zhi Wu
- Department of Anesthesiology, First Affiliated Hospital of Nanchang University, NO. 17, Yongwaizheng Street, Nanchang, Jiangxi, 330006, China.,Department of Anesthesiology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), NO.568, North Zhongxing Road, Shaoxing, Zhejiang, China
| | - Hai-Mei Xia
- Department of Anesthesiology, First Affiliated Hospital of Nanchang University, NO. 17, Yongwaizheng Street, Nanchang, Jiangxi, 330006, China
| | - Ping Zhang
- Department of Anesthesiology, Jiangxi Provincial People's Hospital, NO.152 Aiguo Road, Nanchang, Jiangxi, 330006, China
| | - Lei Li
- Department of Anesthesiology, First Affiliated Hospital of Nanchang University, NO. 17, Yongwaizheng Street, Nanchang, Jiangxi, 330006, China
| | - Qiao-Hao Hu
- Department of Anesthesiology, First Affiliated Hospital of Nanchang University, NO. 17, Yongwaizheng Street, Nanchang, Jiangxi, 330006, China
| | - Su-Ping Guo
- Department of Ultrasound Medicine, First Affiliated Hospital of Nanchang University, NO. 17, Yongwaizheng Street, Nanchang, Jiangxi, 330006, China
| | - Tian-Yuan Li
- Department of Anesthesiology, First Affiliated Hospital of Nanchang University, NO. 17, Yongwaizheng Street, Nanchang, Jiangxi, 330006, China.
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Santos TBR, Nakanishi RM, de Camargo EDLB, Amato MBP, Kaipio JP, Lima RG, Mueller JL. Improved resolution of D-bar images of ventilation using a Schur complement property and an anatomical atlas. Med Phys 2022; 49:4653-4670. [PMID: 35411573 PMCID: PMC9544658 DOI: 10.1002/mp.15669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 03/31/2022] [Accepted: 03/31/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Electrical impedance tomography (EIT) is a nonionizing imaging technique for real-time imaging of ventilation of patients with respiratory distress. Cross-sectional dynamic images are formed by reconstructing the conductivity distribution from measured voltage data arising from applied alternating currents on electrodes placed circumferentially around the chest. Since the conductivity of lung tissue depends on air content, blood flow, and the presence of pathology, the dynamic images provide regional information about ventilation, pulsatile perfusion, and abnormalities. However, due to the ill-posedness of the inverse conductivity problem, EIT images have a coarse spatial resolution. One method of improving the resolution is to include prior information in the reconstruction. PURPOSE In this work, we propose a technique in which a statistical prior built from an anatomical atlas is used to postprocess EIT reconstructions of human chest data. The effectiveness of the method is demonstrated on data from two patients with cystic fibrosis. METHODS A direct reconstruction algorithm known as the D-bar method was used to compute a two-dimensional reconstruction of the conductivity distribution in the plane of the electrodes. Reconstructions using one step in an iterative (regularized) Newton's method were also computed for comparison. An anatomical atlas consisting of 1589 synthetic EIT images computed from X-ray computed tomography (CT) scans of 74 adult male subjects was computed for use as a statistical prior. The resolution of the D-bar images was then improved by maximizing the conditional probability density function of an image that is consistent with the a priori information and the statistical model. A new method to evaluate the accuracy of the EIT images using CT scans of the imaged patient as ground truth is presented. The novel approach is tested on data from two patients with cystic fibrosis. RESULTS AND CONCLUSIONS The D-bar images resulted in better structural similarity index measures (SSIM) and multiscale (MS) SSIM measures for both subjects using the mask or amplitude evaluation approach than the one-step (regularized) Newton's method. Further improvement was achieved using the Schur complement (SC) approach, with MS-SSIM values of 0.718 and 0.682 using SC evaluated with the mask and amplitude approach, respectively, for Patient 1, and MS-SSIM values of 0.726 and 0.692 using SC evaluated with the mask and amplitude approach, respectively, for Patient 2. The results from applying an anatomical atlas and statistical prior to EIT data from two patients with cystic fibrosis suggest that the spatial resolution of the EIT image can be improved to reveal pathology that may be difficult to discern in the original EIT image. The novel metric of evaluation is consistent with the appearance of improved spatial resolution and provides a new way to evaluate the accuracy of EIT reconstructions when a CT scan is available.
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Affiliation(s)
| | - Rafael Mikio Nakanishi
- Mechanical Engineering DepartmentPolytechnic School of the University of São PauloSão PauloSPBrazil
| | | | | | - Jari P. Kaipio
- Department of MathematicsUniversity of AucklandNew Zealand
- Department of Applied PhysicsUniversity of Eastern FinlandKuopioFinland
| | - Raul Gonzalez Lima
- Mechanical Engineering DepartmentPolytechnic School of the University of São PauloSão PauloSPBrazil
| | - Jennifer L. Mueller
- Department of Mathematics and School of Biomedical Engineering and the Department of Electrical and Computer EngineeringColorado State UniversityColoradoUSA
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19
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Rauseo M, Spinelli E, Sella N, Slobod D, Spadaro S, Longhini F, Giarratano A, Gilda C, Mauri T, Navalesi P. Expert opinion document: "Electrical impedance tomography: applications from the intensive care unit and beyond". JOURNAL OF ANESTHESIA, ANALGESIA AND CRITICAL CARE (ONLINE) 2022; 2:28. [PMID: 37386674 DOI: 10.1186/s44158-022-00055-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 06/01/2022] [Indexed: 07/01/2023]
Abstract
Mechanical ventilation is a life-saving technology, but it can also inadvertently induce lung injury and increase morbidity and mortality. Currently, there is no easy method of assessing the impact that ventilator settings have on the degree of lung inssflation. Computed tomography (CT), the gold standard for visually monitoring lung function, can provide detailed regional information of the lung. Unfortunately, it necessitates moving critically ill patients to a special diagnostic room and involves exposure to radiation. A technique introduced in the 1980s, electrical impedance tomography (EIT) can non-invasively provide similar monitoring of lung function. However, while CT provides information on the air content, EIT monitors ventilation-related changes of lung volume and changes of end expiratory lung volume (EELV). Over the past several decades, EIT has moved from the research lab to commercially available devices that are used at the bedside. Being complementary to well-established radiological techniques and conventional pulmonary monitoring, EIT can be used to continuously visualize the lung function at the bedside and to instantly assess the effects of therapeutic maneuvers on regional ventilation distribution. EIT provides a means of visualizing the regional distribution of ventilation and changes of lung volume. This ability is particularly useful when therapy changes are intended to achieve a more homogenous gas distribution in mechanically ventilated patients. Besides the unique information provided by EIT, its convenience and safety contribute to the increasing perception expressed by various authors that EIT has the potential to be used as a valuable tool for optimizing PEEP and other ventilator settings, either in the operative room and in the intensive care unit. The effects of various therapeutic interventions and applications on ventilation distribution have already been assessed with the help of EIT, and this document gives an overview of the literature that has been published in this context.
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Affiliation(s)
- Michela Rauseo
- Department of Anesthesia and Intensive Care Medicine, University of Foggia, Policlinico Riuniti di Foggia, Foggia, Italy.
| | - Elena Spinelli
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico Milan, Milano, Italy
| | - Nicolò Sella
- Instiute of Anesthesia and Intensive Care, Padua University Hospital, Padova, Italy
| | - Douglas Slobod
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico Milan, Milano, Italy
- Department of Critical Care Medicine, McGill University, Montreal, Quebec, Canada
| | - Savino Spadaro
- Anesthesia and Intensive Care Unit, Department of Translational Medicine, University of Ferrara, Ferrara, Italy
| | - Federico Longhini
- Anesthesia and Intensive Care Unit, Department of Medical and Surgical Sciences, "Magna Graecia" University, "Mater Domini" University Hospital, Catanzaro, Italy
| | - Antonino Giarratano
- Department of Surgical, Oncological and Oral Science (Di.Chir.On.S.), Section of Anaesthesia, Analgesia, Intensive Care and Emergency, Policlinico Paolo Giaccone, University of Palermo, Palermo, Italy
| | - Cinnella Gilda
- Department of Anesthesia and Intensive Care Medicine, University of Foggia, Policlinico Riuniti di Foggia, Foggia, Italy
| | - Tommaso Mauri
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico Milan, Milano, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Paolo Navalesi
- Instiute of Anesthesia and Intensive Care, Padua University Hospital, Padova, Italy
- Department of Medicine - DIMED, University of Padua, Padova, Italy
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20
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Bito K, Shono A, Kimura S, Maruta K, Omoto T, Aoki A, Oe K, Kotani T. Clinical Implications of Determining Individualized Positive End-Expiratory Pressure Using Electrical Impedance Tomography in Post-Cardiac Surgery Patients: A Prospective, Non-Randomized Interventional Study. J Clin Med 2022; 11:jcm11113022. [PMID: 35683410 PMCID: PMC9181720 DOI: 10.3390/jcm11113022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 05/14/2022] [Accepted: 05/24/2022] [Indexed: 02/04/2023] Open
Abstract
Optimal positive end-expiratory pressure (PEEP) can induce sustained lung function improvement. This prospective, non-randomized interventional study aimed to investigate the effect of individualized PEEP determined using electrical impedance tomography (EIT) in post-cardiac surgery patients (n = 35). Decremental PEEP trials were performed from 20 to 4 cmH2O in steps of 2 cmH2O, guided by EIT. PEEP levels preventing ventilation loss in dependent lung regions (PEEPONLINE) were set. Ventilation distributions and oxygenation before the PEEP trial, and 5 min and 1 h after the PEEPONLINE setting were examined. Furthermore, we analyzed the saved impedance data offline to determine the PEEP levels that provided the best compromise between overdistended and collapsed lung (PEEPODCL). Ventilation distributions of dependent regions increased at 5 min after the PEEPONLINE setting compared with those before the PEEP trial (mean ± standard deviation, 41.3 ± 8.5% vs. 49.1 ± 9.3%; p < 0.001), and were maintained at 1 h thereafter (48.7 ± 9.4%, p < 0.001). Oxygenation also showed sustained improvement. Rescue oxygen therapy (high-flow nasal cannula, noninvasive ventilation) after extubation was less frequent in patients with PEEPONLINE ≥ PEEPODCL than in those with PEEPONLINE < PEEPODCL (1/19 vs. 6/16; p = 0.018). EIT-guided individualized PEEP stabilized the improvement in ventilation distribution and oxygenation. Individual PEEP varies with EIT measures, and may differentially affect oxygenation after cardiac surgery.
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Affiliation(s)
- Kiyoko Bito
- Department of Anesthesiology, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (S.K.); (K.O.)
- Correspondence: ; Tel.: +81-3-3784-8575
| | - Atsuko Shono
- Department of Intensive Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (A.S.); (T.K.)
| | - Shinya Kimura
- Department of Anesthesiology, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (S.K.); (K.O.)
| | - Kazuto Maruta
- Department of Cardiovascular Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (K.M.); (T.O.); (A.A.)
| | - Tadashi Omoto
- Department of Cardiovascular Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (K.M.); (T.O.); (A.A.)
| | - Atsushi Aoki
- Department of Cardiovascular Surgery, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (K.M.); (T.O.); (A.A.)
| | - Katsunori Oe
- Department of Anesthesiology, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (S.K.); (K.O.)
| | - Toru Kotani
- Department of Intensive Care Medicine, School of Medicine, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan; (A.S.); (T.K.)
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Abstract
OBJECTIVE To describe, through a narrative review, the physiologic principles underlying electrical impedance tomography, and its potential applications in managing acute respiratory distress syndrome (ARDS). To address the current evidence supporting its use in different clinical scenarios along the ARDS management continuum. DATA SOURCES We performed an online search in Pubmed to review articles. We searched MEDLINE, Cochrane Central Register, and clinicaltrials.gov for controlled trials databases. STUDY SELECTION Selected publications included case series, pilot-physiologic studies, observational cohorts, and randomized controlled trials. To describe the rationale underlying physiologic principles, we included experimental studies. DATA EXTRACTION Data from relevant publications were reviewed, analyzed, and its content summarized. DATA SYNTHESIS Electrical impedance tomography is an imaging technique that has aided in understanding the mechanisms underlying multiple interventions used in ARDS management. It has the potential to monitor and predict the response to prone positioning, aid in the dosage of flow rate in high-flow nasal cannula, and guide the titration of positive-end expiratory pressure during invasive mechanical ventilation. The latter has been demonstrated to improve physiologic and mechanical parameters correlating with lung recruitment. Similarly, its use in detecting pneumothorax and harmful patient-ventilator interactions such as pendelluft has been proven effective. Nonetheless, its impact on clinically meaningful outcomes remains to be determined. CONCLUSIONS Electrical impedance tomography is a potential tool for the individualized management of ARDS throughout its different stages. Clinical trials should aim to determine whether a specific approach can improve clinical outcomes in ARDS management.
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22
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Gu M, Deng N, Xia W, Deng L, Liang G. Study protocol for a single-centre randomised controlled trial to investigate the effect of lung recruitment in paediatric patients after cardiac surgery. BMJ Open 2022; 12:e063278. [PMID: 35580972 PMCID: PMC9115041 DOI: 10.1136/bmjopen-2022-063278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
INTRODUCTION A number of published studies have revealed that lung recruitment can improve oxygenation, shorten the duration of mechanical ventilation (MV) and decrease mortality in adults with acute hypoxaemic respiratory failure, especially patients with acute respiratory distress syndrome. However, few articles have assessed lung recruitment in paediatric patients, especially after cardiac surgery. This clinical trial aimed to determine whether lung recruitment can reduce the duration of MV in paediatric patients with hypoxaemic respiratory failure after cardiac surgery. METHOD AND ANALYSIS In this trial, we will randomly assign 234 paediatric patients (aged 28 days to 14 years) within 72 hours after cardiac surgery with an arterial oxygen tension (PaO2) to fraction of inspired oxygen (FiO2) ratio (PaO2/FiO2) of <300 to either a lung recruitment group or a conventional group. The primary endpoint will be the duration of MV. The secondary endpoints will be ventilator-free days, PaO2/FiO2, respiratory system compliance, duration of non-invasive ventilation, reintubation rate, length of intensive care unit stay, length of hospital stay, occurrence of serious adverse events (barotrauma, persistent hypotension and arrhythmia), postoperative pulmonary complications. ETHICS AND DISSEMINATION The ethics committee of West China Hospital of Sichuan University granted ethics approval for this study (20 August 2019). The results will be published in peer-reviewed journals and presented at conferences. TRIAL REGISTRATION NUMBER ChiCTR1900025990.
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Affiliation(s)
- Miaomiao Gu
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, China
| | - Ni Deng
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, China
| | - Wenxi Xia
- Department of Respiratory and Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, China
| | - Lijing Deng
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, China
| | - Guopeng Liang
- Department of Critical Care Medicine, West China Hospital of Sichuan University, Chengdu, China
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23
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Lung Recruitability and Positive End-Expiratory Pressure Setting in ARDS Caused by COVID-19. Chest 2022; 161:869-871. [PMID: 35396041 PMCID: PMC8980520 DOI: 10.1016/j.chest.2021.12.651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 12/29/2021] [Indexed: 12/16/2022] Open
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24
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Bedside Selection of Positive End Expiratory Pressure by Electrical Impedance Tomography in Patients Undergoing Veno-Venous Extracorporeal Membrane Oxygenation Support: A Comparison between COVID-19 ARDS and ARDS from Other Etiologies. J Clin Med 2022; 11:jcm11061639. [PMID: 35329965 PMCID: PMC8955184 DOI: 10.3390/jcm11061639] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/09/2022] [Accepted: 03/14/2022] [Indexed: 12/14/2022] Open
Abstract
Background: The interest in protective ventilation strategies and individualized approaches for patients with severe illness on veno venous extracorporeal support has increased in recent years. Wide heterogeneity exists among patients with COVID-19 related acute respiratory distress syndrome (C-ARDS) and ARDS from other etiologies (NC-ARDS). EIT is a useful tool for the accurate analysis of regional lung volume distribution and allows for a tailored ventilatory setting. The aim of this work is to retrospectively describe the results of EIT assessments performed in patients C-ARDS and NC-ARDS undergoing V-V ECMO support. Methods: A clinical EIT-guided decremental PEEP trail was conducted for all patients included in the study and mechanically ventilated. Results: 12 patients with C-ARDS and 12 patients with NC-ARDS were included in the study for a total of 13 and 18 EIT evaluations, respectively. No significant differences in arterial blood gas, respiratory parameters, and regional ventilation before and after the EIT exam were recorded. The subset of patients with NC-ARDS whose EIT exam led to PEEP modification was characterized by a lower baseline compliance compared with the C-ARDS group: 18 (16–28) vs. 27 (24–30) (p = 0.04). Overdistension significantly increased at higher steps only for the NC-ARDS group. A higher percentage of overdistension was described in patients with NC-ARDS when compared with patients with C-ARDS. Conclusions: EIT is feasible in patients with COVID-19-associated ARDS on veno-venous extracorporeal support and may help in tailoring the PEEP setting. Overall, severe COVID-19-related ARDS presents respiratory characteristics similar to severe “classical” NC-ARDS. However, C-ARDS is associated with a lower risk of overdistension at a higher PEEP level compared with NC-ARDS.
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25
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Electrical impedance tomography in the adult intensive care unit. Curr Opin Crit Care 2022; 28:292-301. [DOI: 10.1097/mcc.0000000000000936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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26
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High-Flow Nasal Cannula Reduces Effort of Breathing But Not Consistently via Positive End-Expiratory Pressure. Chest 2022; 162:861-871. [DOI: 10.1016/j.chest.2022.03.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 03/05/2022] [Accepted: 03/07/2022] [Indexed: 11/23/2022] Open
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27
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Influence of the end inspiratory pause on respiratory mechanics and tidal gas distribution of surgical patients ventilated under a tailored open lung approach strategy: A randomised, crossover trial. Anaesth Crit Care Pain Med 2022; 41:101038. [DOI: 10.1016/j.accpm.2022.101038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 12/09/2021] [Accepted: 12/12/2021] [Indexed: 11/21/2022]
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28
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Artaud-Macari E, Bubenheim M, Le Bouar G, Carpentier D, Grangé S, Boyer D, Béduneau G, Misset B, Cuvelier A, Tamion F, Girault C. High-flow oxygen therapy versus noninvasive ventilation: a randomised physiological crossover study of alveolar recruitment in acute respiratory failure. ERJ Open Res 2021; 7:00373-2021. [PMID: 34912882 PMCID: PMC8666576 DOI: 10.1183/23120541.00373-2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/10/2021] [Indexed: 11/05/2022] Open
Abstract
High-flow nasal cannula (HFNC) oxygen therapy has recently shown clinical benefits in hypoxaemic acute respiratory failure (ARF) patients, while the value of noninvasive ventilation (NIV) remains debated. The primary end-point was to compare alveolar recruitment using global end-expiratory electrical lung impedance (EELI) between HFNC and NIV. Secondary end-points compared regional EELI, lung volumes (global and regional tidal volume variation (VT)), respiratory parameters, haemodynamic tolerance, dyspnoea and patient comfort between HFNC and NIV, relative to face mask (FM). A prospective randomised crossover physiological study was conducted in patients with hypoxaemic ARF due to pneumonia. They received alternately HFNC, NIV and FM. 16 patients were included. Global EELI was 4083 with NIV and 2921 with HFNC (p=0.4). Compared to FM, NIV and HFNC significantly increased global EELI by 1810.5 (95% CI 857–2646) and 826 (95% CI 399.5–2361), respectively. Global and regional VT increased significantly with NIV compared to HFNC or FM, but not between HFNC and FM. NIV yielded a significantly higher pulse oxygen saturation/inspired oxygen fraction ratio compared to HFNC (p=0.03). No significant difference was observed between HFNC, NIV and FM for dyspnoea. Patient comfort score with FM was not significantly different than with HFNC (p=0.1), but was lower with NIV (p=0.001). This study suggests a potential benefit of HFNC and NIV on alveolar recruitment in patients with hypoxaemic ARF. In contrast with HFNC, NIV increased lung volumes, which may contribute to overdistension and its potentially deleterious effect in these patients. This study found a potential benefit of HFNC and NIV on alveolar recruitment in patients with hypoxaemic ARF, but NIV also increases lung volumes, which may give rise to overdistension, reinforcing the concept of patient self-inflicted lung injuryhttps://bit.ly/3iRcZDJ
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Affiliation(s)
- Elise Artaud-Macari
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France.,Rouen University Hospital, Pulmonary, Thoracic Oncology and Respiratory Intensive Care Unit, F-76000, Rouen, France.,Normandie Université, UNIROUEN, EA3830, Rouen University Hospital, F-76000, Rouen, France
| | - Michael Bubenheim
- Rouen University Hospital, Dept of Clinical Research and Innovation, F-76000, Rouen, France
| | - Gurvan Le Bouar
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France.,Rouen University Hospital, Pulmonary, Thoracic Oncology and Respiratory Intensive Care Unit, F-76000, Rouen, France
| | - Dorothée Carpentier
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France
| | - Steven Grangé
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France
| | - Déborah Boyer
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France
| | - Gaëtan Béduneau
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France.,Normandie Université, UNIROUEN, EA3830, Rouen University Hospital, F-76000, Rouen, France
| | - Benoit Misset
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France.,Dept of Intensive Care, Liège University Hospital, Liège, Belgium
| | - Antoine Cuvelier
- Rouen University Hospital, Pulmonary, Thoracic Oncology and Respiratory Intensive Care Unit, F-76000, Rouen, France.,Normandie Université, UNIROUEN, EA3830, Rouen University Hospital, F-76000, Rouen, France
| | - Fabienne Tamion
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France.,Normandie Université, UNIROUEN, IRIB, Inserm U 1096, Rouen University Hospital, F-76000, Rouen, France
| | - Christophe Girault
- Rouen University Hospital, Medical Intensive Care Unit, F-76000, Rouen, France.,Normandie Université, UNIROUEN, EA3830, Rouen University Hospital, F-76000, Rouen, France
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29
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Electrical impedance tomography: A compass for the safe route to optimal PEEP. Respir Med 2021; 187:106555. [PMID: 34352563 DOI: 10.1016/j.rmed.2021.106555] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 11/20/2022]
Abstract
Setting the proper level of positive end-expiratory pressure (PEEP) is a cornerstone of lung protective ventilation. PEEP keeps the alveoli open at the end of expiration, thus reducing atelectrauma and shunt. However, excessive PEEP may contribute to alveolar overdistension. Electrical impedance tomography (EIT) is a non-invasive bedside tool that monitors in real-time ventilation distribution. Aim of this narrative review is summarizing the techniques for EIT-guided PEEP titration, while providing useful insights to enhance comprehension on advantages and limits of EIT for current and future users. EIT detects thoracic impedance to alternating electrical currents between pairs of electrodes and, through the analysis of its temporal and spatial variation, reconstructs a two-dimensional slice image of the lung depicting regional variation of ventilation and perfusion. Several EIT-based methods have been proposed for PEEP titration. The first described technique estimates the variations of regional lung compliance during a decremental PEEP trial, after lung recruitment. The optimal PEEP value is represented by the best compromise between lung collapse and overdistension. Later on, a second technique assessing alveolar recruitment by variation of the end-expiratory lung impedance was validated. Finally, the global inhomogeneity index and the regional ventilation delay, two EIT-derived parameters, showed promising results selecting the optimal PEEP value as the one that presents the lowest global inhomogeneity index or the lowest regional ventilation delay. In conclusion EIT represents a promising technique to individualize PEEP in mechanically ventilated patients. Whether EIT is the best technique for this purpose and the overall influence of personalizing PEEP on clinical outcome remains to be determined.
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Bronco A, Grassi A, Meroni V, Giovannoni C, Rabboni F, Rezoagli E, Teggia-Droghi M, Foti G, Bellani G. Clinical value of electrical impedance tomography (EIT) in the management of patients with acute respiratory failure: a single centre experience. Physiol Meas 2021; 42. [PMID: 34167097 DOI: 10.1088/1361-6579/ac0e85] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/24/2021] [Indexed: 12/22/2022]
Abstract
Objective.We will describe our clinical experience using electrical impedance tomography (EIT) in the management of mechanical ventilation in patients with acute respiratory failure and to determine to which extent EIT-guided positive end-expiratory pressure (PEEP) setting differed from clinically set values.Approach.We conducted a retrospective, observational cohort study performed in a hub centre for the treatment of acute respiratory failure and veno-venous extracorporeal membrane oxygenation (ECMO).Main results.Between January 2017 and December 2019, EIT was performed 54 times in 41 patients, not feasible only in one case because of signal instability. More than 50% was on veno-venous ECMO support. In 16 cases (30%), EIT was used for monitoring mechanical ventilation, i.e. to evaluate recruitability or sigh setting. In 37 cases (70%), EIT was used to set PEEP both with incremental (11 cases in nine patients) and decremental (26 cases, 18 patients) PEEP trial. Clinical PEEP before the decremental PEEP trial (PEEPPRE) was 14.1 ± 3.4 cmH2O and clinical PEEP set by clinicians after the PEEP trial (PEEPPOST) was 13.6 ± 3.1 (p = ns). EIT analyses demonstrated that more hypoxic patients were higher derecruited when compared to less hypoxic patients that were, on the contrary, more overdistended (p < 0.05). No acute effects of PEEP adjustment based on EIT on respiratory mechanics or regional EIT parameters modification were observed.Significance.The variability of EIT findings in our population confirmed the need to provide ventilation settings individually tailored and EIT was confirmed to be an optimal useful clinical bedside noninvasive tool to provide real-time monitoring of the PEEP effect and ventilation distribution.
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Affiliation(s)
- Alfio Bronco
- Department of Emergency and Intensive Care, ASST Monza, Monza, Italy
| | - Alice Grassi
- Department of Anesthesiology and Pain Medicine, University of Toronto, Toronto (ON), Canada
| | - Valeria Meroni
- Department of Emergency and Intensive Care, ASST Monza, Monza, Italy
| | | | - Francesca Rabboni
- Department of Emergency and Intensive Care, ASST Monza, Monza, Italy
| | - Emanuele Rezoagli
- Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | | | - Giuseppe Foti
- Department of Emergency and Intensive Care, ASST Monza, Monza, Italy.,Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | - Giacomo Bellani
- Department of Emergency and Intensive Care, ASST Monza, Monza, Italy.,Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
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Personalized Positive End-Expiratory Pressure and Tidal Volume in Acute Respiratory Distress Syndrome: Bedside Physiology-Based Approach. Crit Care Explor 2021; 3:e0486. [PMID: 34278316 PMCID: PMC8280087 DOI: 10.1097/cce.0000000000000486] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVES: Positive end-expiratory pressure and tidal volume may have a key role for the outcome of patients with acute respiratory distress syndrome. The variety of acute respiratory distress syndrome phenotypes implies personalization of those settings. To guide personalized positive end-expiratory pressure and tidal volume, physicians need to have an in-depth understanding of the physiologic effects and bedside methods to measure the extent of these effects. In the present article, a step-by-step physiologic approach to select personalized positive end-expiratory pressure and tidal volume at the bedside is described. DATA SOURCES: The present review is a critical reanalysis of the traditional and latest literature on the topic. STUDY SELECTION: Relevant clinical and physiologic studies on positive end-expiratory pressure and tidal volume setting were reviewed. DATA EXTRACTION: Reappraisal of the available physiologic and clinical data. DATA SYNTHESIS: Positive end-expiratory pressure is aimed at stabilizing alveolar recruitment, thus reducing the risk of volutrauma and atelectrauma. Bedside assessment of the potential for lung recruitment is a preliminary step to recognize patients who benefit from higher positive end-expiratory pressure level. In patients with higher potential for lung recruitment, positive end-expiratory pressure could be selected by physiology-based methods balancing recruitment and overdistension. In patients with lower potential for lung recruitment or in shock, positive end-expiratory pressure could be maintained in the 5–8 cm H2O range. Tidal volume induces alveolar recruitment and improves gas exchange. After setting personalized positive end-expiratory pressure, tidal volume could be based on lung inflation (collapsed lung size) respecting safety thresholds of static and dynamic lung stress. Positive end-expiratory pressure and tidal volume could be kept stable for some hours in order to allow early recognition of changes in the clinical course of acute respiratory distress syndrome but also frequently reassessed to avoid crossing of safety thresholds. CONCLUSIONS: The setting of personalized positive end-expiratory pressure and tidal volume based on sound physiologic bedside measures may represent an effective strategy for treating acute respiratory distress syndrome patients.
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Diehl JL, Placais M, Rolland M. Transpulmonary Pressure-Guided Invasive Ventilation in Morbidly Obese Patients: Another Brick in the Wall of Personalized Medicine. Respir Care 2021; 66:1224-1225. [PMID: 34210745 DOI: 10.4187/respcare.09356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jean-Luc Diehl
- Department of Intensive CareBiosurgical Research Lab (Carpentier Foundation)Georges Pompidou European HospitalParis, FranceDepartment of Innovative Therapies in HemostasisINSERM UMR_S 1140 Université de ParisParis, France
| | - Marion Placais
- Department of Intensive CareBiosurgical Research Lab (Carpentier Foundation)Georges Pompidou European HospitalParis, FranceDepartment of Innovative Therapies in HemostasisINSERM UMR_S 1140 Université de ParisParis, France
| | - Marine Rolland
- Department of Intensive CareBiosurgical Research Lab (Carpentier Foundation)Georges Pompidou European HospitalParis, FranceDepartment of Innovative Therapies in HemostasisINSERM UMR_S 1140 Université de ParisParis, France
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Pierrakos C, Smit MR, Hagens LA, Heijnen NFL, Hollmann MW, Schultz MJ, Paulus F, Bos LDJ. Assessment of the Effect of Recruitment Maneuver on Lung Aeration Through Imaging Analysis in Invasively Ventilated Patients: A Systematic Review. Front Physiol 2021; 12:666941. [PMID: 34149448 PMCID: PMC8212037 DOI: 10.3389/fphys.2021.666941] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/20/2021] [Indexed: 12/16/2022] Open
Abstract
Background: Recruitment maneuvers (RMs) have heterogeneous effects on lung aeration and have adverse side effects. We aimed to identify morphological, anatomical, and functional imaging characteristics that might be used to predict the RMs on lung aeration in invasively ventilated patients. Methods: We performed a systemic review. Studies included invasively ventilated patients who received an RM and in whom re-aeration was examined with chest computed tomography (CT), electrical impedance tomography (EIT), and lung ultrasound (LUS) were included. Results: Twenty studies were identified. Different types of RMs were applied. The amount of re-aerated lung tissue after an RM was highly variable between patients in all studies, irrespective of the used imaging technique and the type of patients (ARDS or non-ARDS). Imaging findings suggesting a non-focal morphology (i.e., radiologic findings consistent with attenuations with diffuse or patchy loss of aeration) were associated with higher likelihood of recruitment and lower chance of overdistention than a focal morphology (i.e., radiological findings suggestive of lobar or segmental loss of aeration). This was independent of the used imaging technique but only observed in patients with ARDS. In patients without ARDS, the results were inconclusive. Conclusions: ARDS patients with imaging findings suggestive of non-focal morphology show most re-aeration of previously consolidated lung tissue after RMs. The role of imaging techniques in predicting the effect of RMs on re-aeration in patients without ARDS remains uncertain.
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Affiliation(s)
- Charalampos Pierrakos
- Department of Intensive Care, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Department of Intensive Care, Brugmann University Hospital, Université Libre de Bruxelles, Brussels, Belgium
| | - Marry R Smit
- Department of Intensive Care, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Laura A Hagens
- Department of Intensive Care, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Nanon F L Heijnen
- Department of Intensive Care, Maastricht UMC+, Maastricht, Netherlands
| | - Markus W Hollmann
- Laboratory of Experimental Intensive Care and Anesthesiology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Department of Anesthesiology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Marcus J Schultz
- Department of Intensive Care, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Laboratory of Experimental Intensive Care and Anesthesiology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Mahidol University, Bangkok, Thailand.,Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Frederique Paulus
- Department of Intensive Care, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Lieuwe D J Bos
- Department of Intensive Care, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Laboratory of Experimental Intensive Care and Anesthesiology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Department of Respiratory Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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Becher T, Buchholz V, Hassel D, Meinel T, Schädler D, Frerichs I, Weiler N. Individualization of PEEP and tidal volume in ARDS patients with electrical impedance tomography: a pilot feasibility study. Ann Intensive Care 2021; 11:89. [PMID: 34080074 PMCID: PMC8171998 DOI: 10.1186/s13613-021-00877-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 05/17/2021] [Indexed: 01/20/2023] Open
Abstract
Background In mechanically ventilated patients with acute respiratory distress syndrome (ARDS), electrical impedance tomography (EIT) provides information on alveolar cycling and overdistension as well as assessment of recruitability at the bedside. We developed a protocol for individualization of positive end-expiratory pressure (PEEP) and tidal volume (VT) utilizing EIT-derived information on recruitability, overdistension and alveolar cycling. The aim of this study was to assess whether the EIT-based protocol allows individualization of ventilator settings without causing lung overdistension, and to evaluate its effects on respiratory system compliance, oxygenation and alveolar cycling. Methods 20 patients with ARDS were included. Initially, patients were ventilated according to the recommendations of the ARDS Network with a VT of 6 ml per kg predicted body weight and PEEP adjusted according to the lower PEEP/FiO2 table. Subsequently, ventilator settings were adjusted according to the EIT-based protocol once every 30 min for a duration of 4 h. To assess global overdistension, we determined whether lung stress and strain remained below 27 mbar and 2.0, respectively. Results Prospective optimization of mechanical ventilation with EIT led to higher PEEP levels (16.5 [14–18] mbar vs. 10 [8–10] mbar before optimization; p = 0.0001) and similar VT (5.7 ± 0.92 ml/kg vs. 5.8 ± 0.47 ml/kg before optimization; p = 0.96). Global lung stress remained below 27 mbar in all patients and global strain below 2.0 in 19 out of 20 patients. Compliance remained similar, while oxygenation was significantly improved and alveolar cycling was reduced after EIT-based optimization. Conclusions Adjustment of PEEP and VT using the EIT-based protocol led to individualization of ventilator settings with improved oxygenation and reduced alveolar cycling without promoting global overdistension. Trial registrationThis study was registered at clinicaltrials.gov (NCT02703012) on March 9, 2016 before including the first patient. Supplementary Information The online version contains supplementary material available at 10.1186/s13613-021-00877-7.
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Affiliation(s)
- Tobias Becher
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany.
| | - Valerie Buchholz
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Daniel Hassel
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Timo Meinel
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Dirk Schädler
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
| | - Norbert Weiler
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany
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Extracorporeal Gas Exchange for Acute Respiratory Distress Syndrome: Open Questions, Controversies and Future Directions. MEMBRANES 2021; 11:membranes11030172. [PMID: 33670987 PMCID: PMC7997339 DOI: 10.3390/membranes11030172] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 02/06/2023]
Abstract
Veno-venous extracorporeal membrane oxygenation (V-V ECMO) in acute respiratory distress syndrome (ARDS) improves gas exchange and allows lung rest, thus minimizing ventilation-induced lung injury. In the last forty years, a major technological and clinical improvement allowed to dramatically improve the outcome of patients treated with V-V ECMO. However, many aspects of the care of patients on V-V ECMO remain debated. In this review, we will focus on main issues and controversies on caring of ARDS patients on V-V ECMO support. Particularly, the indications to V-V ECMO and the feasibility of a less invasive extracorporeal carbon dioxide removal will be discussed. Moreover, the controversies on management of mechanical ventilation, prone position and sedation will be explored. In conclusion, we will discuss evidences on transfusions and management of anticoagulation, also focusing on patients who undergo simultaneous treatment with ECMO and renal replacement therapy. This review aims to discuss all these clinical aspects with an eye on future directions and perspectives.
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Hsu HJ, Chang HT, Zhao Z, Wang PH, Zhang JH, Chen YS, Frerichs I, Möller K, Fu F, Hsu HS, Chuang SP, Hsia HY, Yen DHT. Positive end-expiratory pressure titration with electrical impedance tomography and pressure-volume curve: a randomized trial in moderate to severe ARDS. Physiol Meas 2021; 42:014002. [PMID: 33361553 DOI: 10.1088/1361-6579/abd679] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE The aim of the study was to compare titration of positive end-expiratory pressure (PEEP) with electrical impedance tomography (EIT) and with ventilator-embedded pressure-volume (PV) loop in moderate to severe acute respiratory distress syndrome (ARDS). APPROACH Eighty-seven moderate to severe ARDS patients (arterial oxygen partial pressure to fractional inspired oxygen ratio, PaO2/FiO2 ≤ 200 mmHg) were randomized to either EIT group (n = 42) or PV group (n = 45). All patients received identical medical care using the same general support guidelines and protective mechanical ventilation. In the EIT group, the selected PEEP equaled the airway pressure at the intercept between cumulated collapse and overdistension percentages curves and in the PV group, at the pressure where maximal hysteresis was reached. MAIN RESULTS Baseline characteristics and settings were comparable between the groups. After optimization, PEEP was significantly higher in the PV group (17.4 ± 1.7 versus 16.2 ± 2.6 cmH2O, PV versus EIT groups, p = 0.02). After 48 h, driving pressure was significantly higher in the PV group (12.4 ± 3.6 versus 10.9 ± 2.5 cmH2O, p = 0.04). Lung mechanics and oxygenation were better in the EIT group but did not statistically differ between the groups. The survival rate was lower in the PV group (44.4% versus 69.0%, p = 0.02; hazard ratio 2.1, confidence interval 1·1-3.9). None of the other pre-specified exploratory clinical endpoints were significantly different. SIGNIFICANCE In moderate to severe ARDS, PEEP titration guided with EIT, compared with PV curve, might be associated with improved driving pressure and survival rate. TRIAL REGISTRATION NCT03112512, 13 April, 2017.
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Affiliation(s)
- Hui-Ju Hsu
- Institute of Emergency and Critical Care Medicine, National Yang-Ming University, Taipei, Taiwan. Department of Internal Medicine, Far Eastern Memorial Hospital, Taipei, Taiwan
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Assessment of electrical impedance tomography to set optimal positive end-expiratory pressure for veno-venous ECMO-treated severe ARDS patients. J Crit Care 2020; 60:38-44. [DOI: 10.1016/j.jcrc.2020.06.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/07/2020] [Accepted: 06/28/2020] [Indexed: 11/22/2022]
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Hahn G, Niewenhuys J, Just A, Tonetti T, Behnemann T, Rapetti F, Collino F, Vasques F, Maiolo G, Romitti F, Gattinoni L, Quintel M, Moerer O. Monitoring lung impedance changes during long-term ventilator-induced lung injury ventilation using electrical impedance tomography. Physiol Meas 2020; 41:095011. [PMID: 33035199 DOI: 10.1088/1361-6579/abb1fb] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE The target of this methodological evaluation was the feasibility of long-term monitoring of changes in lung conditions by time-difference electrical impedance tomography (tdEIT). In contrast to ventilation monitoring by tdEIT, the monitoring of end-expiratory (EELIC) or end-inspiratory (EILIC) lung impedance change always requires a reference measurement. APPROACH To determine the stability of the used Pulmovista 500® EIT system, as a prerequisite it was initially secured on a resistive phantom for 50 h. By comparing the slopes of EELIC for the whole lung area up to 48 h from 36 pigs ventilated at six positive end-expiratory pressure (PEEP) levels from 0 to 18 cmH2O we found a good agreement (range of r 2 = 0.93-1.0) between absolute EIT (aEIT) and tdEIT values. This justified the usage of tdEIT with its superior local resolution compared to aEIT for long-term determination of EELIC. MAIN RESULTS The EELIC was between -0.07 Ωm day-1 at PEEP 4 and -1.04 Ωm day-1 at PEEP 18 cmH2O. The complex local time pattern for EELIC was roughly quantified by the new parameter, centre of end-expiratory change (CoEEC), in equivalence to the established centre of ventilation (CoV). The ventrally located mean of the CoV was fairly constant in the range of 42%-46% of thorax diameter; however, on the contrary, the CoEEC shifted from about 40% to about 75% in the dorsal direction for PEEP levels of 14 and 18 cmH2O. SIGNIFICANCE The observed shifts started earlier for higher PEEP levels. Changes of EELI could be precisely monitored over a period of 48 h by tdEIT on pigs.
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Affiliation(s)
- G Hahn
- Department of Anaesthesiology, University Medical Center Göttingen (UMG), Robert-Koch-Str. 40, D-37075, Göttingen, Germany
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Dalla Corte F, Mauri T, Spinelli E, Lazzeri M, Turrini C, Albanese M, Abbruzzese C, Lissoni A, Galazzi A, Eronia N, Bronco A, Maffezzini E, Pesenti A, Foti G, Bellani G, Grasselli G. Dynamic bedside assessment of the physiologic effects of prone position in acute respiratory distress syndrome patients by electrical impedance tomography. Minerva Anestesiol 2020; 86:1057-1064. [DOI: 10.23736/s0375-9393.20.14130-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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40
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Grieco DL, Bongiovanni F, Chen L, Menga LS, Cutuli SL, Pintaudi G, Carelli S, Michi T, Torrini F, Lombardi G, Anzellotti GM, De Pascale G, Urbani A, Bocci MG, Tanzarella ES, Bello G, Dell’Anna AM, Maggiore SM, Brochard L, Antonelli M. Respiratory physiology of COVID-19-induced respiratory failure compared to ARDS of other etiologies. Crit Care 2020; 24:529. [PMID: 32859264 PMCID: PMC7453378 DOI: 10.1186/s13054-020-03253-2] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/17/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Whether respiratory physiology of COVID-19-induced respiratory failure is different from acute respiratory distress syndrome (ARDS) of other etiologies is unclear. We conducted a single-center study to describe respiratory mechanics and response to positive end-expiratory pressure (PEEP) in COVID-19 ARDS and to compare COVID-19 patients to matched-control subjects with ARDS from other causes. METHODS Thirty consecutive COVID-19 patients admitted to an intensive care unit in Rome, Italy, and fulfilling moderate-to-severe ARDS criteria were enrolled within 24 h from endotracheal intubation. Gas exchange, respiratory mechanics, and ventilatory ratio were measured at PEEP of 15 and 5 cmH2O. A single-breath derecruitment maneuver was performed to assess recruitability. After 1:1 matching based on PaO2/FiO2, FiO2, PEEP, and tidal volume, COVID-19 patients were compared to subjects affected by ARDS of other etiologies who underwent the same procedures in a previous study. RESULTS Thirty COVID-19 patients were successfully matched with 30 ARDS from other etiologies. At low PEEP, median [25th-75th percentiles] PaO2/FiO2 in the two groups was 119 mmHg [101-142] and 116 mmHg [87-154]. Average compliance (41 ml/cmH2O [32-52] vs. 36 ml/cmH2O [27-42], p = 0.045) and ventilatory ratio (2.1 [1.7-2.3] vs. 1.6 [1.4-2.1], p = 0.032) were slightly higher in COVID-19 patients. Inter-individual variability (ratio of standard deviation to mean) of compliance was 36% in COVID-19 patients and 31% in other ARDS. In COVID-19 patients, PaO2/FiO2 was linearly correlated with respiratory system compliance (r = 0.52 p = 0.003). High PEEP improved PaO2/FiO2 in both cohorts, but more remarkably in COVID-19 patients (p = 0.005). Recruitability was not different between cohorts (p = 0.39) and was highly inter-individually variable (72% in COVID-19 patients and 64% in ARDS from other causes). In COVID-19 patients, recruitability was independent from oxygenation and respiratory mechanics changes due to PEEP. CONCLUSIONS Early after establishment of mechanical ventilation, COVID-19 patients follow ARDS physiology, with compliance reduction related to the degree of hypoxemia, and inter-individually variable respiratory mechanics and recruitability. Physiological differences between ARDS from COVID-19 and other causes appear small.
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Affiliation(s)
- Domenico Luca Grieco
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Filippo Bongiovanni
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Lu Chen
- Keenan Centre for Biomedical Research, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Canada
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada
| | - Luca S. Menga
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Salvatore Lucio Cutuli
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Gabriele Pintaudi
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Simone Carelli
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Teresa Michi
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Flava Torrini
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Gianmarco Lombardi
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Gian Marco Anzellotti
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Gennaro De Pascale
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Andrea Urbani
- Department of Basic Biotechnological Science, Università Cattolica del Sacro Cuore, Rome, Italy
- Department of Laboratory and Infectious Diseases, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Maria Grazia Bocci
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Eloisa S. Tanzarella
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Giuseppe Bello
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Antonio M. Dell’Anna
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Salvatore M. Maggiore
- Department of Medical, Oral and Biotechnological Sciences, School of Medicine and Health Sciences, Section of Anesthesia, Analgesia, Perioperative and Intensive Care, SS. Annunziata Hospital, Gabriele d’Annunzio University of Chieti-Pescara, Chieti, Italy
| | - Laurent Brochard
- Keenan Centre for Biomedical Research, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, Canada
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada
| | - Massimo Antonelli
- Department of Emergency, Intensive Care Medicine and Anesthesia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Anestesiologia e Rianimazione, Università Cattolica del Sacro Cuore, Rome, Italy
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Individualized PEEP ventilation between tumor resection and dural suture in craniotomy. Clin Neurol Neurosurg 2020; 196:106027. [PMID: 32673939 DOI: 10.1016/j.clineuro.2020.106027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/03/2020] [Accepted: 06/14/2020] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Atelectasis, which affects oxygenation, is always occurred after craniotomy under general anesthesia. The commonly used protective ventilation strategy, which includes recruitment maneuver and higher level of positive end-expiratory pressure (PEEP), can effectively reduce atelectasis after heart and abdominal surgery, but increase intracranial pressure and reduce cerebral perfusion in patients undergoing craniotomy. We hypothesized individualized PEEP ventilation between tumor resection and dural suture in craniotomy could effectively reduce postoperative atelectasis, improve PaO2/FiO2 ratio, and without reducing the regional cerebral oxygen saturation (rScO2). PATIENTS AND METHODS 96 patients underwent tumor craniotomy in supine position were randomized into the control group (C group) and individualized PEEP group (P group). In the C group, the tidal volume (VT) was set at 8 mL/kg of predicted body weight, but PEEP were not used. In the P group, VT was set at 6 mL/kg of predicted body weight combined with individualized PEEP between tumor resection and dural suture, while in other periods of general anesthesia, VT was set at 8 mL/kg of predicted body weight. PaO2/FiO2 ratio, lung ultrasound score (LUS) and rScO2 were measured before induction, 1 h and 24 h after extubation. RESULTS Individual PEEP in the P group was 7.0 (4.0-9.0). The PaO2/FiO2 ratio and rScO2 in the P group were significantly higher than that of the C group (395 ± 62 vs. 344 ± 40, 67 ± 5 vs. 61 ± 4, respectively, p < 0.05) and the LUS of the experimental group was significantly lower than that of the C group [7.5 (5.3-8.3) vs. 10.0 (9.0-12.0), p < 0.05] 1 h after extubation. CONCLUSION Mechanical ventilation with individualized PEEP between tumor resection and dural suture in craniotomy can reduce atelectasis, improve PaO2/FiO2 ratio and rScO2 1 h after extubation.
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Individualized Positive End-expiratory Pressure and Regional Gas Exchange in Porcine Lung Injury. Anesthesiology 2020; 132:808-824. [DOI: 10.1097/aln.0000000000003151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Abstract
Background
In acute respiratory failure elevated intraabdominal pressure aggravates lung collapse, tidal recruitment, and ventilation inhomogeneity. Low positive end-expiratory pressure (PEEP) may promote lung collapse and intrapulmonary shunting, whereas high PEEP may increase dead space by inspiratory overdistension. The authors hypothesized that an electrical impedance tomography–guided PEEP approach minimizing tidal recruitment improves regional ventilation and perfusion matching when compared to a table-based low PEEP/no recruitment and an oxygenation-guided high PEEP/full recruitment strategy in a hybrid model of lung injury and elevated intraabdominal pressure.
Methods
In 15 pigs with oleic acid–induced lung injury intraabdominal pressure was increased by intraabdominal saline infusion. PEEP was set in randomized order: (1) guided by a PEEP/inspired oxygen fraction table, without recruitment maneuver; (2) minimizing tidal recruitment guided by electrical impedance tomography after a recruitment maneuver; and (3) maximizing oxygenation after a recruitment maneuver. Single photon emission computed tomography was used to analyze regional ventilation, perfusion, and aeration. Primary outcome measures were differences in PEEP levels and regional ventilation/perfusion matching.
Results
Resulting PEEP levels were different (mean ± SD) with (1) table PEEP: 11 ± 3 cm H2O; (2) minimal tidal recruitment PEEP: 22 ± 3 cm H2O; and (3) maximal oxygenation PEEP: 25 ± 4 cm H2O; P < 0.001. Table PEEP without recruitment maneuver caused highest lung collapse (28 ± 11% vs. 5 ± 5% vs. 4 ± 4%; P < 0.001), shunt perfusion (3.2 ± 0.8 l/min vs. 1.0 ± 0.8 l/min vs. 0.7 ± 0.6 l/min; P < 0.001) and dead space ventilation (2.9 ± 1.0 l/min vs. 1.5 ± 0.7 l/min vs. 1.7 ± 0.8 l/min; P < 0.001). Although resulting in different PEEP levels, minimal tidal recruitment and maximal oxygenation PEEP, both following a recruitment maneuver, had similar effects on regional ventilation/perfusion matching.
Conclusions
When compared to table PEEP without a recruitment maneuver, both minimal tidal recruitment PEEP and maximal oxygenation PEEP following a recruitment maneuver decreased shunting and dead space ventilation, and the effects of minimal tidal recruitment PEEP and maximal oxygenation PEEP were comparable.
Editor’s Perspective
What We Already Know about This Topic
What This Article Tells Us That Is New
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Becher T, Wendler A, Eimer C, Weiler N, Frerichs I. Changes in Electrical Impedance Tomography Findings of ICU Patients during Rapid Infusion of a Fluid Bolus: A Prospective Observational Study. Am J Respir Crit Care Med 2020; 199:1572-1575. [PMID: 30875244 DOI: 10.1164/rccm.201812-2252le] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Tobias Becher
- 1 University Medical Center Schleswig-Holstein Kiel, Germany
| | - Anna Wendler
- 1 University Medical Center Schleswig-Holstein Kiel, Germany
| | - Christine Eimer
- 1 University Medical Center Schleswig-Holstein Kiel, Germany
| | - Norbert Weiler
- 1 University Medical Center Schleswig-Holstein Kiel, Germany
| | - Inéz Frerichs
- 1 University Medical Center Schleswig-Holstein Kiel, Germany
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Rezoagli E, Bellani G. How I set up positive end-expiratory pressure: evidence- and physiology-based! Crit Care 2019; 23:412. [PMID: 31842915 PMCID: PMC6916086 DOI: 10.1186/s13054-019-2695-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 12/06/2019] [Indexed: 12/16/2022] Open
Affiliation(s)
- Emanuele Rezoagli
- Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy
| | - Giacomo Bellani
- Department of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy. .,Department of Emergency and Intensive Care, San Gerardo Hospital, Monza, Italy.
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Zhao Z, Lee LC, Chang MY, Frerichs I, Chang HT, Gow CH, Hsu YL, Möller K. The incidence and interpretation of large differences in EIT-based measures for PEEP titration in ARDS patients. J Clin Monit Comput 2019; 34:1005-1013. [PMID: 31587120 DOI: 10.1007/s10877-019-00396-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 09/26/2019] [Indexed: 12/18/2022]
Abstract
Positive end-expiratory pressure (PEEP) can be titrated by electrical impedance tomography (EIT). The aim of the present study was to examine the performance of different EIT measures during PEEP trials with the aim of identifying "optimum" PEEP and to provide possible interpretations of largely diverging results. After recruitment (maximum plateau pressure 35 cmH2O), decremental PEEP trial with steps of 2 cmH2O and duration of 2 min per step was performed. Ventilation gain and loss, the global inhomogeneity (GI) index, trend of end-expiratory lung impedance (EELI) and regional compliance (Creg) for estimation of overdistension and collapse were calculated. Largely diverging results of PEEP selection among the measures were defined as differences ≥ 4 PEEP steps (i.e. ≥ 8 cmH2O). In 30 ARDS patients we examined so far, 3 patients showed significant differences in PEEP selections. Overdistension and collapse estimation based on Creg tended to select lower PEEP while the GI index and EELI trend suggested higher PEEP settings. Regional inspiration times were heterogeneous indicating that the assumption of a uniform driving pressure in the calculation of Creg may not be valid. Judging by the predominant ventilation distribution in the most dependent regions, these patients were non-recruitable with the applied recruitment method or pressure levels. The existence of differences in the recommended PEEP among the analyzed EIT measures might be an indicator of non-recruitable lungs and heterogeneous airway resistances. In these extreme cases, the largely diverging results may prompt the attending clinician to develop individual ventilation strategies.Clinical Trial Registration Registration number NCT03112512, https://clinicaltrials.gov/ Registered 13 April 2017.
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Affiliation(s)
- Zhanqi Zhao
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China.,Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
| | - Li-Chung Lee
- Department of Internal Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, Taiwan
| | - Mei-Yun Chang
- Department of Internal Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, Taiwan
| | - Inez Frerichs
- Department of Anaesthesiology and Intensive Care Medicine, University Medical Centre of Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Hou-Tai Chang
- Department of Internal Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, Taiwan.
| | - Chien-Hung Gow
- Department of Internal Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, Taiwan
| | - Yeong-Long Hsu
- Department of Internal Medicine, Far Eastern Memorial Hospital, No. 21, Sec. 2, Nanya S. Rd., Banciao Dist., New Taipei City, Taiwan. .,Department of Healthcare Management, College of Medical Technology and Nursing, Yuanpei University of Medical Technology, No. 306 Yuanpei Street, Hsinchu, Taiwan.
| | - Knut Möller
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
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Thürk F, Elenkov M, Waldmann AD, Böhme S, Braun C, Adler A, Kaniusas E. Influence of reconstruction settings in electrical impedance tomography on figures of merit and physiological parameters. Physiol Meas 2019; 40:094003. [DOI: 10.1088/1361-6579/ab248e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Rodriguez M, Thille AW, Boissier F, Veinstein A, Chatellier D, Robert R, Le Pape S, Frat JP, Coudroy R. Predictors of successful separation from high-flow nasal oxygen therapy in patients with acute respiratory failure: a retrospective monocenter study. Ann Intensive Care 2019; 9:101. [PMID: 31511996 PMCID: PMC6738360 DOI: 10.1186/s13613-019-0578-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 09/05/2019] [Indexed: 01/04/2023] Open
Abstract
Background High-flow nasal oxygen therapy (HFOT) is a promising first-line therapy for acute respiratory failure. However, its weaning has never been investigated and could lead to unnecessary prolonged intensive-care unit (ICU) stay. The aim of this study is to assess predictors of successful separation from HFOT in critically ill patients. We performed a retrospective monocenter observational study over a 2-year period including all patients treated with HFOT for acute respiratory failure in the ICU. Those who died or were intubated without prior HFOT separation attempt, who were treated with non-invasive ventilation at the time of HFOT separation, or who received HFOT as a preventive treatment during the post-extubation period were excluded. Results From the 190 patients analyzed, 168 (88%) were successfully separated from HFOT at the first attempt. Patients who failed separation from HFOT at the first attempt had longer ICU length of stay than those who succeeded: 10 days (7–12) vs. 5 (4–8), p < 0.0001. Fraction of inspired oxygen (FiO2) ≤ 40% and a respiratory rate-oxygenation (ROX) index (calculated as the ratio of SpO2/FiO2 to the respiratory rate) ≥ 9.2 predicted successful separation from HFOT with sensitivity of 85% and 84%, respectively. Conclusions FiO2 ≤ 40% and ROX index ≥ 9.2 were two predictors of successful separation from HFOT at the bedside. Prospective multicenter studies are needed to confirm these results.
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Affiliation(s)
- Maeva Rodriguez
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France
| | - Arnaud W Thille
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France.,INSERM CIC 1402, ALIVE Group, Université de Poitiers, Poitiers, France
| | - Florence Boissier
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France.,INSERM CIC 1402, ALIVE Group, Université de Poitiers, Poitiers, France
| | - Anne Veinstein
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France
| | - Delphine Chatellier
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France
| | - René Robert
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France.,INSERM CIC 1402, ALIVE Group, Université de Poitiers, Poitiers, France
| | - Sylvain Le Pape
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France.,INSERM CIC 1402, ALIVE Group, Université de Poitiers, Poitiers, France
| | - Jean-Pierre Frat
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France.,INSERM CIC 1402, ALIVE Group, Université de Poitiers, Poitiers, France
| | - Remi Coudroy
- Médecine Intensive et Réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86000, Poitiers, France. .,INSERM CIC 1402, ALIVE Group, Université de Poitiers, Poitiers, France.
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Spinelli E, Mauri T, Fogagnolo A, Scaramuzzo G, Rundo A, Grieco DL, Grasselli G, Volta CA, Spadaro S. Electrical impedance tomography in perioperative medicine: careful respiratory monitoring for tailored interventions. BMC Anesthesiol 2019; 19:140. [PMID: 31390977 PMCID: PMC6686519 DOI: 10.1186/s12871-019-0814-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 07/29/2019] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Electrical impedance tomography (EIT) is a non-invasive radiation-free monitoring technique that provides images based on tissue electrical conductivity of the chest. Several investigations applied EIT in the context of perioperative medicine, which is not confined to the intraoperative period but begins with the preoperative assessment and extends to postoperative follow-up. MAIN BODY EIT could provide careful respiratory monitoring in the preoperative assessment to improve preparation for surgery, during anaesthesia to guide optimal ventilation strategies and to monitor the hemodynamic status and in the postoperative period for early detection of respiratory complications. Moreover, EIT could further enhance care of patients undergoing perioperative diagnostic procedures. This narrative review summarizes the latest evidence on the application of this technique to the surgical patient, focusing also on possible future perspectives. CONCLUSIONS EIT is a promising technique for the perioperative assessment of surgical patients, providing tailored adaptive respiratory and haemodynamic monitoring. Further studies are needed to address the current technological limitations, confirm the findings and evaluate which patients can benefit more from this technology.
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Affiliation(s)
- Elena Spinelli
- Dipartimento di Anestesia, Rianimazione ed Emergenza-Urgenza, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli studi di Milano, Milan, Italy
| | - Tommaso Mauri
- Dipartimento di Anestesia, Rianimazione ed Emergenza-Urgenza, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli studi di Milano, Milan, Italy
| | - Alberto Fogagnolo
- Department Morphology, Surgery and Experimental medicine, Anesthesia and Intensive care section, University of Ferrara, Azienda Ospedaliera- Universitaria Sant'Anna, 8, Aldo Moro, Ferrara, Italy
| | - Gaetano Scaramuzzo
- Department Morphology, Surgery and Experimental medicine, Anesthesia and Intensive care section, University of Ferrara, Azienda Ospedaliera- Universitaria Sant'Anna, 8, Aldo Moro, Ferrara, Italy
| | - Annalisa Rundo
- UOC Anestesia e Rianimazione, Polo ospedaliero Belcolle ASL, Viterbo, Italy
| | - Domenico Luca Grieco
- Department of Anesthesiology and Intensive Care Medicine, Catholic University of the Sacred Heart, Fondazione "Policlinico Universitario A. Gemelli", Rome, Italy
| | - Giacomo Grasselli
- Dipartimento di Anestesia, Rianimazione ed Emergenza-Urgenza, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Università degli studi di Milano, Milan, Italy
| | - Carlo Alberto Volta
- Department Morphology, Surgery and Experimental medicine, Anesthesia and Intensive care section, University of Ferrara, Azienda Ospedaliera- Universitaria Sant'Anna, 8, Aldo Moro, Ferrara, Italy
| | - Savino Spadaro
- Department Morphology, Surgery and Experimental medicine, Anesthesia and Intensive care section, University of Ferrara, Azienda Ospedaliera- Universitaria Sant'Anna, 8, Aldo Moro, Ferrara, Italy.
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Bauer M, Opitz A, Filser J, Jansen H, Meffert RH, Germer CT, Roewer N, Muellenbach RM, Kredel M. Perioperative redistribution of regional ventilation and pulmonary function: a prospective observational study in two cohorts of patients at risk for postoperative pulmonary complications. BMC Anesthesiol 2019; 19:132. [PMID: 31351452 PMCID: PMC6661098 DOI: 10.1186/s12871-019-0805-8] [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: 11/17/2018] [Accepted: 07/18/2019] [Indexed: 11/30/2022] Open
Abstract
Background Postoperative pulmonary complications (PPCs) increase morbidity and mortality of surgical patients, duration of hospital stay and costs. Postoperative atelectasis of dorsal lung regions as a common PPC has been described before, but its clinical relevance is insufficiently examined. Pulmonary electrical impedance tomography (EIT) enables the bedside visualization of regional ventilation in real-time within a transversal section of the lung. Dorsal atelectasis or effusions might cause a ventral redistribution of ventilation. We hypothesized the existence of ventral redistribution in spontaneously breathing patients during their recovery from abdominal and peripheral surgery and that vital capacity is reduced if regional ventilation shifts to ventral lung regions. Methods This prospective observational study included 69 adult patients undergoing elective surgery with an expected intermediate or high risk for PPCs. Patients undergoing abdominal and peripheral surgery were recruited to obtain groups of equal size. Patients received general anesthesia with and without additional regional anesthesia. On the preoperative, the first and the third postoperative day, EIT was performed at rest and during spirometry (forced breathing). The center of ventilation in dorso-ventral direction (COVy) was calculated. Results Both groups received intraoperative low tidal volume ventilation. Postoperative ventral redistribution of ventilation (forced breathing COVy; preoperative: 16.5 (16.0–17.3); first day: 17.8 (16.9–18.2), p < 0.004; third day: 17.4 (16.2–18.2), p = 0.020) and decreased forced vital capacity in percentage of predicted values (FVC%predicted) (median: 93, 58, 64%, respectively) persisted after abdominal surgery. In addition, dorsal to ventral shift was associated with a decrease of the FVC%predicted on the third postoperative day (r = − 0.66; p < 0.001). A redistribution of pulmonary ventilation was not observed after peripheral surgery. FVC%predicted was only decreased on the first postoperative day (median FVC%predicted on the preoperative, first and third day: 85, 81 and 88%, respectively). In ten patients occurred pulmonary complications after abdominal surgery also in two patients after peripheral surgery. Conclusions After abdominal surgery ventral redistribution of ventilation persisted up to the third postoperative day and was associated with decreased vital capacity. The peripheral surgery group showed only minor changes in vital capacity, suggesting a role of the location of surgery for postoperative redistribution of pulmonary ventilation. Trial registration This prospective observational single centre study was submitted to registration prior to patient enrollment at ClinicalTrials.gov (NCT02419196, Date of registration: December 1, 2014). Registration was finalized at April 17, 2015. Electronic supplementary material The online version of this article (10.1186/s12871-019-0805-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maria Bauer
- Department of Anaesthesia and Critical Care, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Anne Opitz
- Department of Anaesthesia and Critical Care, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Jörg Filser
- Department of General, Visceral, Transplantation, Vascular and Paediatric Surgery, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Hendrik Jansen
- Department of Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Rainer H Meffert
- Department of Trauma, Hand, Plastic and Reconstructive Surgery, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Christoph T Germer
- Department of General, Visceral, Transplantation, Vascular and Paediatric Surgery, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Norbert Roewer
- Department of Anaesthesia and Critical Care, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Ralf M Muellenbach
- Department of Anaesthesia and Critical Care, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany
| | - Markus Kredel
- Department of Anaesthesia and Critical Care, University Hospital of Würzburg, University of Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany.
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Event-triggered averaging of electrical impedance tomography (EIT) respiratory waveforms as compared to low-pass filtering for removal of cardiac related impedance changes. J Clin Monit Comput 2019; 34:553-558. [PMID: 31278546 PMCID: PMC7223993 DOI: 10.1007/s10877-019-00348-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Accepted: 07/01/2019] [Indexed: 11/08/2022]
Abstract
Electrical impedance tomography (EIT) is used for bedside ventilation monitoring; cardiac related impedance changes represent a source of noise superimposed on the ventilation signal, commonly removed by low-pass filtering (LPF). We investigated if an alternative approach, based on an event-triggered averaging (ETA) process, is more effective at preserving the actual ventilation waveform. Ten paralyzed patients undergoing volume-controlled ventilation were studied; 30 breaths for each patient were identified to compare LPF and ETA. For ETA the identified breaths were temporally aligned on the beginning of inspiration; the values of the thirty curves at each time point were averaged. The analysis was conducted on the global EIT signal and on four ventral-to-dorsal regions of interest. Global tidal variations by ETA resulted higher than LPF (average difference 139 ± 88 arbitrary units, p = 0.004). Both for global and regional waveforms, minimum and maximum EIT slopes were steeper by ETA as compared to LPF (average difference respectively − 57 ± 60 mL/s and 144 ± 96 mL/s for global signal, p < 0.05); ventilator inspiratory peak airflow correlated with maximum slope measured by ETA (r = 0.902, p < 0.001), but not LPF (p = 0.319). Beginning of inspiration identified on the ventilator waveform and on the global EIT signal by ETA occurred simultaneously, (+ 0.04 ± 0.07 s, p = 0.081), while occurred earlier by LPF (− 0.26 ± 0.1 s, p < 0.001). Removal of cardiac related impedance changes by ETA results in a ventilation signal more similar to the waveforms recorded by the ventilator, particularly regarding the slope of impedance changes and time at the minimum values as compared to LPF.
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