1
|
Lee JH, Kang P, Park JB, Ji SH, Jang YE, Kim EH, Kim JT, Kim HS. Determination of optimal positive end-expiratory pressure using electrical impedance tomography in infants under general anesthesia: Comparison between supine and prone positions. Paediatr Anaesth 2024; 34:758-767. [PMID: 38693633 DOI: 10.1111/pan.14914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 04/04/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024]
Abstract
AIMS This study determined the optimal positive end-expiratory pressure levels in infants in supine and prone positions under general anesthesia using electrical impedance tomography (EIT). METHODS This prospective observational single-centre study included infants scheduled for surgery in the prone position. An electrical impedance tomography sensor was applied after inducing general anesthesia. The optimal positive end-expiratory pressure in the supine position was determined in a decremental trial based on EIT and compliance. Subsequently, the patient's position was changed to prone. Electrical impedance tomography parameters, including global inhomogeneity index, regional ventilation delay, opening pressure, the centre of ventilation, and pendelluft volume, were continuously obtained up to 1 h after prone positioning. The optimal positive end-expiratory pressure in the prone position was similarly determined. RESULTS Data from 30 infants were analyzed. The mean value of electrical impedance tomography-based optimal positive end-expiratory pressure in the prone position was significantly higher than that in the supine position [10.9 (1.6) cmH2O and 6.1 (0.9) cmH2O, respectively (p < .001)]. Significant differences were observed between electrical impedance tomography- and compliance-based optimal positive end-expiratory pressure. Peak and mean airway, plateau, and driving pressures increased 1 h after prone positioning compared with those in the supine position. In addition, the centre of ventilation for balance in ventilation between the ventral and dorsal regions improved. CONCLUSION The prone position required higher positive end-expiratory pressure than the supine position in mechanically ventilated infants under general anesthesia. EIT is a promising tool to find the optimal positive end-expiratory pressure, which needs to be individualized.
Collapse
Affiliation(s)
- Ji-Hyun Lee
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Pyoyoon Kang
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Jung-Bin Park
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Sang-Hwan Ji
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Young-Eun Jang
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Eun-Hee Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Jin-Tae Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Hee-Soo Kim
- Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| |
Collapse
|
2
|
García-Sanz V, Canfrán S, Gómez de Segura IA, Aguado D. Effect of end-inspiratory pause duration on respiratory system compliance calculation in mechanically ventilated dogs with healthy lungs. Vet Anaesth Analg 2024; 51:333-342. [PMID: 38772855 DOI: 10.1016/j.vaa.2024.03.009] [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: 02/21/2022] [Revised: 03/01/2024] [Accepted: 03/20/2024] [Indexed: 05/23/2024]
Abstract
OBJECTIVE To compare respiratory system compliance (CRS), expressed per kilogram of bodyweight (CRSBW), calculated without end-inspiratory pause (EIP) and after three EIP times (0.2, 0.5 and 1 seconds) with that after 3 second EIP (considered the reference EIP for static CRS) and to determine the EIP times that provided CRSBW values in acceptable agreement with static CRSBW during controlled mechanical ventilation (CMV) in anaesthetized dogs. STUDY DESIGN Prospective, randomized, nonblinded, crossover clinical study. ANIMALS A group of 24 client-owned dogs with healthy lungs undergoing surgery in lateral recumbency. METHODS During CMV in dogs undergoing general anaesthesia, five EIPs [0 (no EIP), 0.2, 0.5, 1 and 3 seconds] were consecutively applied in random order. Tidal volume (Vt) was set at 10 mL kg-1 and positive end-expiratory pressure (PEEP) was not applied. Respiratory rate and inspiratory time were established according to each EIP time, setting EIP between 0 and 50% of the inspiratory time. The CRSBW was calculated as [expired Vt/(plateau pressure - PEEP)]/bodyweight and recorded every 15 seconds for 2 minutes after a 5 minute equilibration period with each EIP. One-way anova for repeated measures and the Bland-Altman analysis were used to compare CRSBW and evaluate agreement between EIP times, respectively. RESULTS The CRSBW was significantly greater as the EIP time increased up to 1 second (p < 0.05). In the Bland-Altman analysis, none of the tested EIPs (0, 0.2, 0.5 and 1 seconds) provided 95% confidence intervals for limits of agreement within the maximum allowed difference considered for acceptable agreement with 3 second EIP. CONCLUSIONS and clinical relevance An EIP ≤ to 1 second does not provide a CRSBW value in acceptable agreement with static CRSBW in healthy dogs. Besides, the application of an EIP ≤ to 0.5 seconds underestimates the static CRSBW to an increasing extent as the EIP time decreases.
Collapse
Affiliation(s)
- Virginia García-Sanz
- Department of Animal Medicine and Surgery, Veterinary Teaching Hospital, Veterinary Faculty, Complutense University of Madrid, Madrid, Spain
| | - Susana Canfrán
- Department of Animal Medicine and Surgery, Veterinary Teaching Hospital, Veterinary Faculty, Complutense University of Madrid, Madrid, Spain.
| | - Ignacio A Gómez de Segura
- Department of Animal Medicine and Surgery, Veterinary Teaching Hospital, Veterinary Faculty, Complutense University of Madrid, Madrid, Spain
| | - Delia Aguado
- Department of Animal Medicine and Surgery, Veterinary Teaching Hospital, Veterinary Faculty, Complutense University of Madrid, Madrid, Spain
| |
Collapse
|
3
|
Arellano DH, Brito R, Morais CCA, Ruiz-Rudolph P, Gajardo AIJ, Guiñez DV, Lazo MT, Ramirez I, Rojas VA, Cerda MA, Medel JN, Illanes V, Estuardo NR, Bruhn AR, Brochard LJ, Amato MBP, Cornejo RA. Pendelluft in hypoxemic patients resuming spontaneous breathing: proportional modes versus pressure support ventilation. Ann Intensive Care 2023; 13:131. [PMID: 38117367 PMCID: PMC10733241 DOI: 10.1186/s13613-023-01230-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 12/10/2023] [Indexed: 12/21/2023] Open
Abstract
BACKGROUND Internal redistribution of gas, referred to as pendelluft, is a new potential mechanism of effort-dependent lung injury. Neurally-adjusted ventilatory assist (NAVA) and proportional assist ventilation (PAV +) follow the patient's respiratory effort and improve synchrony compared with pressure support ventilation (PSV). Whether these modes could prevent the development of pendelluft compared with PSV is unknown. We aimed to compare pendelluft magnitude during PAV + and NAVA versus PSV in patients with resolving acute respiratory distress syndrome (ARDS). METHODS Patients received either NAVA, PAV + , or PSV in a crossover trial for 20-min using comparable assistance levels after controlled ventilation (> 72 h). We assessed pendelluft (the percentage of lost volume from the non-dependent lung region displaced to the dependent region during inspiration), drive (as the delta esophageal swing of the first 100 ms [ΔPes 100 ms]) and inspiratory effort (as the esophageal pressure-time product per minute [PTPmin]). We performed repeated measures analysis with post-hoc tests and mixed-effects models. RESULTS Twenty patients mechanically ventilated for 9 [5-14] days were monitored. Despite matching for a similar tidal volume, respiratory drive and inspiratory effort were slightly higher with NAVA and PAV + compared with PSV (ΔPes 100 ms of -2.8 [-3.8--1.9] cm H2O, -3.6 [-3.9--2.4] cm H2O and -2.1 [-2.5--1.1] cm H2O, respectively, p < 0.001 for both comparisons; PTPmin of 155 [118-209] cm H2O s/min, 197 [145-269] cm H2O s/min, and 134 [93-169] cm H2O s/min, respectively, p < 0.001 for both comparisons). Pendelluft magnitude was higher in NAVA (12 ± 7%) and PAV + (13 ± 7%) compared with PSV (8 ± 6%), p < 0.001. Pendelluft magnitude was strongly associated with respiratory drive (β = -2.771, p-value < 0.001) and inspiratory effort (β = 0.026, p < 0.001), independent of the ventilatory mode. A higher magnitude of pendelluft in proportional modes compared with PSV existed after adjusting for PTPmin (β = 2.606, p = 0.010 for NAVA, and β = 3.360, p = 0.004 for PAV +), and only for PAV + when adjusted for respiratory drive (β = 2.643, p = 0.009 for PAV +). CONCLUSIONS Pendelluft magnitude is associated with respiratory drive and inspiratory effort. Proportional modes do not prevent its occurrence in resolving ARDS compared with PSV.
Collapse
Affiliation(s)
- Daniel H Arellano
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
- Departamento de Kinesiología, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Roberto Brito
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - Caio C A Morais
- Divisao de Pneumologia, Faculdade de Medicina, Instituto Do Coração, Hospital das Clinicas HCFMUSP, Universidade de São Paulo, São Paulo, Brazil
- Departamento de Fisioterapia, Universidade Federal de Pernambuco, Recife, Brazil
| | - Pablo Ruiz-Rudolph
- Programa de Epidemiología, Facultad de Medicina, Instituto de Salud Poblacional, Universidad de Chile, Santiago, Chile
| | - Abraham I J Gajardo
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
- Programa de Fisiopatología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Dannette V Guiñez
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - Marioli T Lazo
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - Ivan Ramirez
- Escuela de Kinesiología, Universidad Diego Portales, Santiago, Chile
| | - Verónica A Rojas
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - María A Cerda
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - Juan N Medel
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - Victor Illanes
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - Nivia R Estuardo
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile
| | - Alejandro R Bruhn
- Departamento de Medicina Intensiva, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center of Acute Respiratory Critical Illness (ARCI), Santiago, Chile
| | - Laurent J Brochard
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, Toronto, Canada
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| | - Marcelo B P Amato
- Divisao de Pneumologia, Faculdade de Medicina, Instituto Do Coração, Hospital das Clinicas HCFMUSP, Universidade de São Paulo, São Paulo, Brazil
| | - Rodrigo A Cornejo
- Departamento de Medicina, Unidad de Pacientes Críticos, Hospital Clínico Universidad de Chile, Dr. Carlos Lorca Tobar 999, 8380456, Santiago, Chile.
- Center of Acute Respiratory Critical Illness (ARCI), Santiago, Chile.
| |
Collapse
|
4
|
Farré R, Navajas D. Ventilation Mechanics. Semin Respir Crit Care Med 2023; 44:511-525. [PMID: 37467769 DOI: 10.1055/s-0043-1770340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
A fundamental task of the respiratory system is to operate as a mechanical gas pump ensuring that fresh air gets in close contact with the blood circulating through the lung capillaries to achieve O2 and CO2 exchange. To ventilate the lungs, the respiratory muscles provide the pressure required to overcome the viscoelastic mechanical load of the respiratory system. From a mechanical viewpoint, the most relevant respiratory system properties are the resistance of the airways (R aw), and the compliance of the lung tissue (C L) and chest wall (C CW). Both airflow and lung volume changes in spontaneous breathing and mechanical ventilation are determined by applying the fundamental mechanical laws to the relationships between the pressures inside the respiratory system (at the airway opening, alveolar, pleural, and muscular) and R aw, C L, and C CW. These relationships also are the basis of the different methods available to measure respiratory mechanics during spontaneous and artificial ventilation. Whereas a simple mechanical model (R aw, C L, and C CW) describes the basic understanding of ventilation mechanics, more complex concepts (nonlinearity, inhomogeneous ventilation, or viscoelasticity) should be employed to better describe and measure ventilation mechanics in patients.
Collapse
Affiliation(s)
- Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut Investigacions Biomediques August Pi Sunyer, Barcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut de Bioenginyeria de Catalunya (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain
| |
Collapse
|
5
|
Takahashi K, Toyama H, Ejima Y, Yang J, Kikuchi K, Ishikawa T, Yamauchi M. Endotracheal tube, by the venturi effect, reduces the efficacy of increasing inlet pressure in improving pendelluft. PLoS One 2023; 18:e0291319. [PMID: 37708106 PMCID: PMC10501657 DOI: 10.1371/journal.pone.0291319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 08/27/2023] [Indexed: 09/16/2023] Open
Abstract
In mechanically ventilated severe acute respiratory distress syndrome patients, spontaneous inspiratory effort generates more negative pressure in the dorsal lung than in the ventral lung. The airflow caused by this pressure difference is called pendelluft, which is a possible mechanisms of patient self-inflicted lung injury. This study aimed to use computer simulation to understand how the endotracheal tube and insufficient ventilatory support contribute to pendelluft. We established two models. In the invasive model, an endotracheal tube was connected to the tracheobronchial tree with 34 outlets grouped into six locations: the right and left upper, lower, and middle lobes. In the non-invasive model, the upper airway, including the glottis, was connected to the tracheobronchial tree. To recreate the inspiratory effort of acute respiratory distress syndrome patients, the lower lobe pressure was set at -13 cmH2O, while the upper and middle lobe pressure was set at -6.4 cmH2O. The inlet pressure was set from 10 to 30 cmH2O to recreate ventilatory support. Using the finite volume method, the total flow rates through each model and toward each lobe were calculated. The invasive model had half the total flow rate of the non-invasive model (1.92 L/s versus 3.73 L/s under 10 cmH2O, respectively). More pendelluft (gas flow into the model from the outlets) was observed in the invasive model than in the non-invasive model. The inlet pressure increase from 10 to 30 cmH2O decreased pendelluft by 11% and 29% in the invasive and non-invasive models, respectively. In the invasive model, a faster jet flowed from the tip of the endotracheal tube toward the lower lobes, consequently entraining gas from the upper and middle lobes. Increasing ventilatory support intensifies the jet from the endotracheal tube, causing a venturi effect at the bifurcation in the tracheobronchial tree. Clinically acceptable ventilatory support cannot completely prevent pendelluft.
Collapse
Affiliation(s)
- Kazuhiro Takahashi
- Anesthesiology and Perioperative Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroaki Toyama
- Anesthesiology and Perioperative Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yutaka Ejima
- Division of Surgical Center and Supply, Sterilization, Tohoku University Hospital, Sendai, Japan
| | - Jinyou Yang
- Department of Biophysics, School of Intelligent Medicine, China Medical University, Shenyang, China
| | - Kenji Kikuchi
- Department of Finemechanics, Graduate School of Engineering, Tohoku University, Sendai, Japan
| | - Takuji Ishikawa
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
| | - Masanori Yamauchi
- Anesthesiology and Perioperative Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| |
Collapse
|
6
|
Beloncle FM, Richard JC, Merdji H, Desprez C, Pavlovsky B, Yvin E, Piquilloud L, Olivier PY, Chean D, Studer A, Courtais A, Campfort M, Rahmani H, Lesimple A, Meziani F, Mercat A. Advanced respiratory mechanics assessment in mechanically ventilated obese and non-obese patients with or without acute respiratory distress syndrome. Crit Care 2023; 27:343. [PMID: 37667379 PMCID: PMC10476380 DOI: 10.1186/s13054-023-04623-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 08/22/2023] [Indexed: 09/06/2023] Open
Abstract
BACKGROUND Respiratory mechanics is a key element to monitor mechanically ventilated patients and guide ventilator settings. Besides the usual basic assessments, some more complex explorations may allow to better characterize patients' respiratory mechanics and individualize ventilation strategies. These advanced respiratory mechanics assessments including esophageal pressure measurements and complete airway closure detection may be particularly relevant in critically ill obese patients. This study aimed to comprehensively assess respiratory mechanics in obese and non-obese ICU patients with or without ARDS and evaluate the contribution of advanced respiratory mechanics assessments compared to basic assessments in these patients. METHODS All intubated patients admitted in two ICUs for any cause were prospectively included. Gas exchange and respiratory mechanics including esophageal pressure and end-expiratory lung volume (EELV) measurements and low-flow insufflation to detect complete airway closure were assessed in standardized conditions (tidal volume of 6 mL kg-1 predicted body weight (PBW), positive end-expiratory pressure (PEEP) of 5 cmH2O) within 24 h after intubation. RESULTS Among the 149 analyzed patients, 52 (34.9%) were obese and 90 (60.4%) had ARDS (65.4% and 57.8% of obese and non-obese patients, respectively, p = 0.385). A complete airway closure was found in 23.5% of the patients. It was more frequent in obese than in non-obese patients (40.4% vs 14.4%, p < 0.001) and in ARDS than in non-ARDS patients (30% vs. 13.6%, p = 0.029). Respiratory system and lung compliances and EELV/PBW were similarly decreased in obese patients without ARDS and obese or non-obese patients with ARDS. Chest wall compliance was not impacted by obesity or ARDS, but end-expiratory esophageal pressure was higher in obese than in non-obese patients. Chest wall contribution to respiratory system compliance differed widely between patients but was not predictable by their general characteristics. CONCLUSIONS Most respiratory mechanics features are similar in obese non-ARDS and non-obese ARDS patients, but end-expiratory esophageal pressure is higher in obese patients. A complete airway closure can be found in around 25% of critically ill patients ventilated with a PEEP of 5 cmH2O. Advanced explorations may allow to better characterize individual respiratory mechanics and adjust ventilation strategies in some patients. Trial registration NCT03420417 ClinicalTrials.gov (February 5, 2018).
Collapse
Affiliation(s)
- François M Beloncle
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France.
- CNRS, INSERM 1083, MITOVASC, University of Angers, Angers, France.
| | - Jean-Christophe Richard
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
- Med2Lab, ALMS, Antony, France
| | - Hamid Merdji
- Medical ICU, University Hospital of Strasbourg, University of Strasbourg, Strasbourg, France
- UMR 1260, Regenerative Nanomedicine (RNM), FMTS, INSERM (French National Institute of Health and Medical Research), Strasbourg, France
| | - Christophe Desprez
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| | - Bertrand Pavlovsky
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| | - Elise Yvin
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| | - Lise Piquilloud
- Adult Intensive Care Unit, University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Pierre-Yves Olivier
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| | - Dara Chean
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| | - Antoine Studer
- Medical ICU, University Hospital of Strasbourg, University of Strasbourg, Strasbourg, France
| | - Antonin Courtais
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| | - Maëva Campfort
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| | - Hassene Rahmani
- Medical ICU, University Hospital of Strasbourg, University of Strasbourg, Strasbourg, France
| | - Arnaud Lesimple
- CNRS, INSERM 1083, MITOVASC, University of Angers, Angers, France
- Med2Lab, ALMS, Antony, France
| | - Ferhat Meziani
- Medical ICU, University Hospital of Strasbourg, University of Strasbourg, Strasbourg, France
- UMR 1260, Regenerative Nanomedicine (RNM), FMTS, INSERM (French National Institute of Health and Medical Research), Strasbourg, France
| | - Alain Mercat
- Medical ICU, University Hospital of Angers, Vent'Lab, University of Angers, 4 Rue Larrey, 49933, Angers Cedex 9, France
| |
Collapse
|
7
|
Hernández Garcés H, Belenguer Muncharaz A, Zaragoza Crespo R. Inspiratory flow: The lost variable? Med Intensiva 2023; 47:554-555. [PMID: 37308359 DOI: 10.1016/j.medine.2023.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/11/2023] [Accepted: 05/13/2023] [Indexed: 06/14/2023]
|
8
|
Cruces P, Moreno D, Reveco S, Ramirez Y, Díaz F. Plateau Pressure and Driving Pressure in Volume- and Pressure-Controlled Ventilation: Comparison of Frictional and Viscoelastic Resistive Components in Pediatric Acute Respiratory Distress Syndrome. Pediatr Crit Care Med 2023; 24:750-759. [PMID: 37260322 DOI: 10.1097/pcc.0000000000003291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
OBJECTIVES To examine frictional, viscoelastic, and elastic resistive components, as well threshold pressures, during volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) in pediatric patients with acute respiratory distress syndrome (ARDS). DESIGN Prospective cohort study. SETTING Seven-bed PICU, Hospital El Carmen de Maipú, Chile. PATIENTS Eighteen mechanically ventilated patients less than or equal to 15 years old undergoing neuromuscular blockade as part of management for ARDS. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS All patients were in VCV mode during measurement of pulmonary mechanics, including: the first pressure drop (P1) upon reaching zero flow during the inspiratory hold, peak inspiratory pressure (PIP), plateau pressure (P PLAT ), and total positive end-expiratory pressure (tPEEP). We calculated the components of the working pressure, as defined by the following: frictional resistive = PIP-P1; viscoelastic resistive = P1-P PLAT ; purely elastic = driving pressure (ΔP) = P PLAT -tPEEP; and threshold = intrinsic PEEP. The procedures and calculations were repeated on PCV, keeping the same tidal volume and inspiratory time. Measurements in VCV were considered the gold standard. We performed Spearman correlation and Bland-Altman analysis. The median (interquartile range [IQR]) for patient age was 5 months (2-17 mo). Tidal volume was 5.7 mL/kg (5.3-6.1 mL/kg), PIP cm H 2 O 26 (23-27 cm H 2 O), P1 23 cm H 2 O (21-26 cm H 2 O), P PLAT 19 cm H 2 O (17-22 cm H 2 O), tPEEP 9 cm H 2 O (8-9 cm H 2 O), and ΔP 11 cm H 2 O (9-13 cm H 2 O) in VCV mode at baseline. There was a robust correlation (rho > 0.8) and agreement between frictional resistive, elastic, and threshold components of working pressure in both modes but not for the viscoelastic resistive component. The purely frictional resistive component was negligible. Median peak inspiratory flow with decelerating-flow was 21 (IQR, 15-26) and squared-shaped flow was 7 L/min (IQR, 6-10 L/min) ( p < 0.001). CONCLUSIONS P PLAT , ΔP, and tPEEP can guide clinical decisions independent of the ventilatory mode. The modest purely frictional resistive component emphasizes the relevance of maintaining the same safety limits, regardless of the selected ventilatory mode. Therefore, peak inspiratory flow should be studied as a mechanism of ventilator-induced lung injury in pediatric ARDS.
Collapse
Affiliation(s)
- Pablo Cruces
- Departamento de Pediatría, Unidad de Paciente Crítico Pediátrico, Hospital El Carmen de Maipú, Santiago, Chile
- Centro de Investigación de Medicina Veterinaria, Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Red Colaborativa Pediátrica de Latinoamérica (LARed Network), Montevideo, Uruguay
- Unidad de Investigación y Epidemiología Clínica, Escuela de Medicina, Universidad Finis Terrae, Santiago, Chile
| | - Diego Moreno
- Departamento de Pediatría, Unidad de Paciente Crítico Pediátrico, Hospital El Carmen de Maipú, Santiago, Chile
| | - Sonia Reveco
- Departamento de Pediatría, Unidad de Paciente Crítico Pediátrico, Hospital El Carmen de Maipú, Santiago, Chile
| | - Yenny Ramirez
- Departamento de Pediatría, Unidad de Paciente Crítico Pediátrico, Hospital El Carmen de Maipú, Santiago, Chile
| | - Franco Díaz
- Departamento de Pediatría, Unidad de Paciente Crítico Pediátrico, Hospital El Carmen de Maipú, Santiago, Chile
- Red Colaborativa Pediátrica de Latinoamérica (LARed Network), Montevideo, Uruguay
- Unidad de Investigación y Epidemiología Clínica, Escuela de Medicina, Universidad Finis Terrae, Santiago, Chile
| |
Collapse
|
9
|
Abram J, Martini J, Spraider P, Putzer G, Ranalter M, Wagner J, Glodny B, Hell T, Barnes T, Enk D. Individualised flow-controlled versus pressure-controlled ventilation in a porcine oleic acid-induced acute respiratory distress syndrome model. Eur J Anaesthesiol 2023; 40:511-520. [PMID: 36749046 PMCID: PMC10256303 DOI: 10.1097/eja.0000000000001807] [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: 02/08/2023]
Abstract
BACKGROUND A continuous gas flow provided by flow-controlled ventilation (FCV) facilitates accurate dynamic compliance measurement and allows the clinician to individually optimise positive end-expiratory and peak pressure settings accordingly. OBJECTIVE The aim of this study was to compare the efficiency of gas exchange and impact on haemodynamics between individualised FCV and pressure-controlled ventilation (PCV) in a porcine model of oleic acid-induced acute respiratory distress syndrome (ARDS). DESIGN Randomised controlled interventional trial conducted on 16 pigs. SETTING Animal operating facility at the Medical University Innsbruck. INTERVENTIONS ARDS was induced in lung healthy pigs by intravenous infusion of oleic acid until moderate-to-severe ARDS at a stable Horowitz quotient (PaO 2 FiO 2-1 ) of 80 to 120 over a period of 30 min was obtained. Ventilation was then either performed with individualised FCV ( n = 8) established by compliance-guided pressure titration or PCV ( n = 8) with compliance-guided titration of the positive end-expiratory pressure and peak pressure set to achieve a tidal volume of 6 ml kg -1 over a period of 2 h. MAIN OUTCOME MEASURES Gas exchange parameters were assessed by the PaO 2 FiO 2-1 quotient and CO 2 removal by the PaCO 2 value in relation to required respiratory minute volume. Required catecholamine support for haemodynamic stabilisation was measured. RESULTS The FCV group showed significantly improved oxygenation [149.2 vs. 110.4, median difference (MD) 38.7 (8.0 to 69.5) PaO 2 FiO 2-1 ; P = 0.027] and CO 2 removal [PaCO 2 7.25 vs. 9.05, MD -1.8 (-2.87 to -0.72) kPa; P = 0.006] at a significantly lower respiratory minute volume [8.4 vs. 11.9, MD -3.6 (-5.6 to -1.5) l min -1 ; P = 0.005] compared with PCV. In addition, in FCV-pigs, haemodynamic stabilisation occurred with a significant reduction of required catecholamine support [norepinephrine 0.26 vs. 0.86, MD -0.61 (-1.12 to -0.09) μg kg -1 min -1 ; P = 0.037] during 2 ventilation hours. CONCLUSION In this oleic acid-induced porcine ARDS model, individualised FCV significantly improved gas exchange and haemodynamic stability compared with PCV. TRIAL REGISTRATION Protocol no.: BMBWF-66.011/0105-V/3b/2019).
Collapse
Affiliation(s)
- Julia Abram
- From the Department of Anaesthesia and Intensive Care Medicine (JA, JM, PS, GP, MR, JW), Department of Radiology, Medical University of Innsbruck (BG), Department of Mathematics, Faculty of Mathematics, Computer Science and Physics, University of Innsbruck, Innsbruck, Austria (TH), University of Greenwich, London, UK (TB), Faculty of Medicine, University of Münster, Münster, Germany (DE)
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Grassetto A, Pettenuzzo T, Badii F, Carlon R, Sella N, Navalesi P. Flow-controlled ventilation may reduce mechanical power and increase ventilatory efficiency in severe coronavirus disease-19 acute respiratory distress syndrome. Pulmonology 2023; 29:154-156. [PMID: 35864057 PMCID: PMC9186429 DOI: 10.1016/j.pulmoe.2022.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 05/15/2022] [Accepted: 05/20/2022] [Indexed: 11/24/2022] Open
Affiliation(s)
- A Grassetto
- Anesthesia and Intensive Care, Vittorio Veneto Hospital, Via C. Forlanini 71, 31029 Vittorio Veneto, Italy.
| | - T Pettenuzzo
- Institute of Anesthesiology and Intensive Care, Padua University Hospital, Padua, Via V. Gallucci 13, 35121 Padua, Italy
| | - F Badii
- Anesthesia and Intensive Care, Vittorio Veneto Hospital, Via C. Forlanini 71, 31029 Vittorio Veneto, Italy
| | - R Carlon
- Anesthesia and Intensive Care, Vittorio Veneto Hospital, Via C. Forlanini 71, 31029 Vittorio Veneto, Italy
| | - N Sella
- Institute of Anesthesiology and Intensive Care, Padua University Hospital, Padua, Via V. Gallucci 13, 35121 Padua, Italy
| | - P Navalesi
- Institute of Anesthesiology and Intensive Care, Padua University Hospital, Padua, Via V. Gallucci 13, 35121 Padua, Italy; Department of Medicine, University of Padua, Via Giustiniani 2, 35128 Padua, Italy
| |
Collapse
|
11
|
Huang HB, Yao Y, Zhu YB, Du B. Awake prone positioning for patients with COVID-19 pneumonia in intensive care unit: A systematic review and meta-analysis. Front Med (Lausanne) 2022; 9:984446. [PMID: 36160173 PMCID: PMC9500207 DOI: 10.3389/fmed.2022.984446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundAwake prone positioning (APP) has been widely used in non-intubated COVID-19 patients during the pandemic. However, high-quality evidence to support its use in severe COVID-19 patients in an intensive care unit (ICU) is inadequate. Therefore, we aimed to assess the efficacy and safety of APP for intubation requirements and other important outcomes in this patient population.MethodsWe searched for potentially relevant articles in PubMed, Embase, and the Cochrane database from inception to May 25, 2022. Studies focusing on COVID-19 adults in ICU who received APP compared to controls were included. The primary outcome was the intubation requirement. Secondary outcomes were mortality, ICU stay, and adverse events. Study quality was independently assessed, and we also conducted subgroup analysis, sensitivity analysis, and publication bias to explore the potential influence factors.ResultsTen randomized controlled trials with 1,686 patients were eligible. The quality of the included studies was low to moderate. Overall, the intubation rate was 35.2% in the included patients. The mean daily APP duration ranged from <6 to 9 h, with poor adherence to APP protocols. When pooling, APP significantly reduced intubation requirement (risk ratio [RR] 0.84; 95%CI, 0.74–0.95; I2 = 0%, P = 0.007). Subgroup analyses confirmed the reduced intubation rates in patients who were older (≥60 years), obese, came from a high mortality risk population (>20%), received HFNC/NIV, had lower SpO2/FiO2 (<150 mmHg), or undergone longer duration of APP (≥8 h). However, APP showed no beneficial effect on mortality (RR 0.92 [95% CI 0.77–1.10; I2 = 0%, P = 0.37] and length of ICU stay (mean difference = −0.58 days; 95% CI, −2.49 to 1.32; I2 = 63%; P = 0.55).ConclusionAPP significantly reduced intubation requirements in ICU patients with COVID-19 pneumonia without affecting the outcomes of mortality and ICU stay. Further studies with better APP protocol adherence will be needed to define the subgroup of patients most likely to benefit from this strategy.
Collapse
Affiliation(s)
- Hui-Bin Huang
- Department of Critical Care Medicine, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Yan Yao
- Department of Critical Care Medicine, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Yi-Bing Zhu
- Department of Emergency, Guang'anmen Hospital, Beijing, China
| | - Bin Du
- Medical ICU, Peking Union Medical College Hospital, Beijing, China
- *Correspondence: Bin Du
| |
Collapse
|
12
|
Crescimanno G, Greco F, Bertini M, Marrone O. Cardiovascular autonomic control during application of different modes of noninvasive ventilation in patients affected by amyotrophic lateral sclerosis. Heart Lung 2022; 56:161-166. [PMID: 35930914 DOI: 10.1016/j.hrtlng.2022.07.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Cardiovascular events commonly cause death in amyotrophic lateral sclerosis (ALS) even in patients treated by noninvasive ventilation (NIV). OBJECTIVES to evaluate autonomic function with the assessment of heart rate variability (HRV) in ALS patients treated by assist pressure control ventilation (APCV) and assist control ventilation (ACV) during sleep. METHODS Consecutive ALS patients underwent one polysomnography during APCV and one during ACV. HRV was analyzed both in the total sleep period (from first stage N1 to last awakening) and in a 5-minute period of stable stage N2. Time domain, frequency domain and nonlinear indexes of HRV were measured. RESULTS Nineteen patients (age 62.0 ± 8.7, 9F/10 M) were studied. The analysis did not reveal differences in blood gasses between NIV modalities, but a longer expiratory time (3.01±0.6 vs 2.8 ± 0.6 s, respectively APCV vs ACV, p = 0.001) and a lower arousal index (17.5 ± 9.1 vs 23.1 ± 13.9, p = 0.02) during APCV. HRV was indicative of higher vagal activity during APCV, especially in the 5-minute periods. In the total sleep periods, the HRV time domain indexes reflecting parasympathetic activity were positively correlated with the expiratory time and negatively with the inspiratory/expiratory time ratio. Low frequencies were positively, and high frequencies negatively, correlated with inspiratory time. HRV and sleep structure parameters were not correlated, except very low frequencies that were correlated to the arousal index. CONCLUSIONS Respiratory influences on autonomic control can be preserved in ALS. The slower breathing pattern during APCV may help to maintain a higher vagal activity. Through this mechanism, in the long-term APCV could more beneficial to ALS patients than ACV.
Collapse
Affiliation(s)
- Grazia Crescimanno
- National Research Council, Institute of Biomedical research and Innovation (IRIB-CNR); Regional Centre for Respiratory Complications of Rare Neuromuscular Diseases, Villa Sofia-Cervello Hospital Palermo.
| | - Francesca Greco
- Italian Union against Muscular Dystrophy, section of Palermo, Italy
| | - Manuela Bertini
- Regional Centre for Respiratory Complications of Rare Neuromuscular Diseases, Villa Sofia-Cervello Hospital Palermo
| | - Oreste Marrone
- National Research Council, Institute of Biomedical research and Innovation (IRIB-CNR)
| |
Collapse
|
13
|
Rezoagli E, Laffey JG, Bellani G. Monitoring Lung Injury Severity and Ventilation Intensity during Mechanical Ventilation. Semin Respir Crit Care Med 2022; 43:346-368. [PMID: 35896391 DOI: 10.1055/s-0042-1748917] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Acute respiratory distress syndrome (ARDS) is a severe form of respiratory failure burden by high hospital mortality. No specific pharmacologic treatment is currently available and its ventilatory management is a key strategy to allow reparative and regenerative lung tissue processes. Unfortunately, a poor management of mechanical ventilation can induce ventilation induced lung injury (VILI) caused by physical and biological forces which are at play. Different parameters have been described over the years to assess lung injury severity and facilitate optimization of mechanical ventilation. Indices of lung injury severity include variables related to gas exchange abnormalities, ventilatory setting and respiratory mechanics, ventilation intensity, and the presence of lung hyperinflation versus derecruitment. Recently, specific indexes have been proposed to quantify the stress and the strain released over time using more comprehensive algorithms of calculation such as the mechanical power, and the interaction between driving pressure (DP) and respiratory rate (RR) in the novel DP multiplied by four plus RR [(4 × DP) + RR] index. These new parameters introduce the concept of ventilation intensity as contributing factor of VILI. Ventilation intensity should be taken into account to optimize protective mechanical ventilation strategies, with the aim to reduce intensity to the lowest level required to maintain gas exchange to reduce the potential for VILI. This is further gaining relevance in the current era of phenotyping and enrichment strategies in ARDS.
Collapse
Affiliation(s)
- Emanuele Rezoagli
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,Department of Emergency and Intensive Care, San Gerardo University Hospital, Monza, Italy
| | - John G Laffey
- School of Medicine, National University of Ireland, Galway, Ireland.,Department of Anaesthesia and Intensive Care Medicine, Galway University Hospitals, Saolta University Hospital Group, Galway, Ireland.,Lung Biology Group, Regenerative Medicine Institute (REMEDI) at CÚRAM Centre for Research in Medical Devices, National University of Ireland Galway, Galway, Ireland
| | - Giacomo Bellani
- School of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,Department of Emergency and Intensive Care, San Gerardo University Hospital, Monza, Italy
| |
Collapse
|
14
|
van Dijk J, Koopman AA, Blokpoel RG, Dijkstra S, Markhorst DG, Burgerhof JG, Kneyber MC. Global and Regional Tidal Volume Distribution in Spontaneously Breathing Mechanically Ventilated Children. Respir Care 2022; 67:383-393. [PMID: 34934009 PMCID: PMC9994001 DOI: 10.4187/respcare.09190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Allowing the ventilated adult patient to breathe spontaneously may improve tidal volume (VT) distribution toward the dependent lung regions, reduce shunt fraction, and decrease dead space. It has not been studied if these effects under various levels of ventilatory support also occur in children. We sought to explore the effect of level of ventilatory support on VT distribution and end-expiratory lung volume (EELV) in spontaneously breathing ventilated children in the recovery phase of their acute respiratory failure. METHODS This is a secondary analysis of data from a prospective clinical trial comparing 2 different ventilator modes during weaning in mechanically ventilated children < 5 y: CPAP + pressure support ventilation (PSV) and pressure control (PC)/intermittent mandatory ventilation (IMV) + PSV with the mandatory breath rate set at 25% of baseline. Using electrical impedance tomography (EIT), we assessed VT distribution by calculating the center of ventilation. Polynomial functions of the second degree were plotted to evaluate regional lung filling characteristics. Changes in end-expiratory impedance were calculated to assess changes in EELV. Baseline measurements were compared with measurements during CPAP/PSV, PC/IMV + PSV, and during a downward titration of the level of pressure support. RESULTS Thirty-five subjects with a median age 4.5 (2.1-12.9) months and a median ventilation time of 4.9 (3.3-6.9) d were studied. The overall median coefficient of variation was 50.1% and not different between CPAP/PSV or PC/synchronized IMV + PSV. Regional filling characteristics of the lung identified a homogeneous VT distribution under all study conditions. Downtapering of the level of PSV resulted in a significant shift of the coefficient of variation toward the dependent lung regions. CONCLUSIONS Our data showed that allowing ventilated children in the recovery phase of respiratory failure to breathe spontaneously in a continuous spontaneous ventilation mode did not negatively affect VT distribution or EELV.
Collapse
Affiliation(s)
- Jefta van Dijk
- Department of Paediatrics, Division of Paediatric Critical Care Medicine, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
| | - Alette A Koopman
- Department of Paediatrics, Division of Paediatric Critical Care Medicine, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Robert Gt Blokpoel
- Department of Paediatrics, Division of Paediatric Critical Care Medicine, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Sandra Dijkstra
- Department of Paediatrics, Division of Paediatric Critical Care Medicine, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Dick G Markhorst
- Department of Paediatrics, Division of Paediatric Critical Care Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Johannes Gm Burgerhof
- Department of Epidemiology, University Medical Center Groningen, The University of Groningen, Groningen, the Netherlands
| | - Martin Cj Kneyber
- Department of Paediatrics, Division of Paediatric Critical Care Medicine, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands and Critical Care, Anaesthesiology, Peri-operative and Emergency Medicine, University of Groningen, Groningen, the Netherlands
| |
Collapse
|
15
|
Ren Y, Zhu X, Yan H, Chen L, Mao Q. Cardiorespiratory impact of intrathoracic pressure overshoot during artificial carbon dioxide pneumothorax: a randomized controlled study. BMC Anesthesiol 2022; 22:76. [PMID: 35321653 PMCID: PMC8941761 DOI: 10.1186/s12871-022-01621-9] [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: 08/10/2021] [Accepted: 03/17/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The aim of this study is to evaluate cardiovascular and respiratory effects of intrathoracic pressure overshoot (higher than insufflation pressure) in patients who underwent thoracoscopic esophagectomy procedures with carbon dioxide (CO2) pneumothorax. METHODS This prospective research included 200 patients who were scheduled for esophagectomy from August 2016 to July 2020. The patients were randomly divided into the Stryker insufflator (STR) group and the Storz insufflator (STO) group. We recorded the changes of intrathoracic pressure, peak airway pressure, blood pressure, heart rate and central venous pressure (CVP) during artificial pneumothorax. The differences in blood gas analysis, the administration of vasopressors and the recovery time were compared between the two groups. RESULTS We found that during the artificial pneumothorax, intrathoracic pressure overshoot occurred in both the STR group (8.9 mmHg, 38 times per hour) and the STO group (9.8 mmHg, 32 times per hour). The recorded maximum intrathoracic pressures were up to 58 mmHg in the STR group and 51 mmHg in the STO group. The average duration of intrathoracic pressure overshoot was significantly longer in the STR group (5.3 ± 0.86 s) vs. the STO group (1.2 ± 0.31 s, P < 0.01). During intrathoracic pressure overshoot, a greater reduction in systolic blood pressure (SBP) (5.6 mmHg vs. 1.1 mmHg, P < 0.01), a higher elevation in airway peak pressure (4.8 ± 1.17 cmH2O vs. 0.9 ± 0.41 cmH2O, P < 0.01), and a larger increase in CVP (8.2 ± 2.86 cmH2O vs. 4.9 ± 2.35 cmH2O, P < 0.01) were observed in the STR group than in the STO group. Vasopressors were also applied more frequently in the STR group than in the STO group (68% vs. 43%, P < 0.01). The reduction of SBP caused by thoracic pressure overshoot was significantly correlated with the duration of overshoot (R = 0.76). No obvious correlation was found between the SBP reduction and the maximum pressure overshoot. CONCLUSIONS Intrathoracic pressure overshoot can occur during thoracoscopic surgery with artificial CO2 pneumothorax and may lead to cardiovascular adverse effects which highly depends on the duration of the pressure overshoot. TRIAL REGISTRATION Clinicaltrials.gov ( NCT02330536 ; December 24, 2014).
Collapse
Affiliation(s)
- Yunqin Ren
- Department of Anesthesiology, Daping Hospital, Army Medical University, 10 ChangjiangZhilu, Yuzhong District, 400042, Chongqing, China
| | - Xing Zhu
- Department of Anesthesiology, Daping Hospital, Army Medical University, 10 ChangjiangZhilu, Yuzhong District, 400042, Chongqing, China
| | - Hong Yan
- Department of Anesthesiology, Daping Hospital, Army Medical University, 10 ChangjiangZhilu, Yuzhong District, 400042, Chongqing, China
| | - Liyong Chen
- Department of Anesthesiology, Daping Hospital, Army Medical University, 10 ChangjiangZhilu, Yuzhong District, 400042, Chongqing, China
| | - Qingxiang Mao
- Department of Anesthesiology, Daping Hospital, Army Medical University, 10 ChangjiangZhilu, Yuzhong District, 400042, Chongqing, China.
| |
Collapse
|
16
|
Chi Y, Zhao Z, Frerichs I, Long Y, He H. Prevalence and prognosis of respiratory pendelluft phenomenon in mechanically ventilated ICU patients with acute respiratory failure: a retrospective cohort study. Ann Intensive Care 2022; 12:22. [PMID: 35246748 PMCID: PMC8897528 DOI: 10.1186/s13613-022-00995-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/11/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Respiratory pendelluft phenomenon, defined as intrapulmonary gas redistribution caused by asynchronous alveolar ventilation, could be potentially harmful by inducing lung injury. The aim of the present study was to investigate its prevalence and prognosis in intensive care unit (ICU) patients with acute respiratory failure (ARF). METHODS This was a retrospective observational study on 200 mechanically ventilated ARF patients treated in a tertiary ICU. The presence of pendelluft was determined using electrical impedance tomography (EIT) within 48 h after admission. Its amplitude was defined as the impedance difference between the sum of all regional tidal impedance variation and the global tidal impedance variation. A value above 2.5% (the 95th percentile from 30 healthy volunteers) was considered confirmative for its occurrence. RESULTS Pendelluft was found in 61 patients (39 in 94 patients with spontaneous breathing, 22 in 106 receiving controlled ventilation), with an overall prevalence of 31%. Existence of spontaneous breathing and higher global inhomogeneity index were associated with pendelluft. Patients with pendelluft had a longer ICU length of stay [10 (6, 14) vs. 7 (4, 11) days; median (lower, upper quartile); p = 0.022] and shorter 14-day ventilator-free days [8 (1, 10) vs. 10 (6, 12) days; p = 0.015]. Subgroup survival analysis suggested the association between pendelluft and longer ventilation duration, which was significant only in patients with PaO2/FiO2 ratio below 200 mmHg (log-rank p = 0.042). ICU mortality did not differ between the patients with and without pendelluft. CONCLUSIONS Respiratory pendelluft occurred often in our study group and it was associated with longer ventilation duration. Early recognition of this phenomenon should trigger interventions aimed at alleviating pendelluft.
Collapse
Affiliation(s)
- Yi Chi
- State Key Laboratory of Complex Severe and Rare Disease, Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, 1 shuaifuyuan, Dongcheng District, Beijing, China
| | - Zhanqi Zhao
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China.,Institute of Technical Medicine, Furtwangen University, VS-Schwenningen, Germany
| | - Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center of Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Yun Long
- State Key Laboratory of Complex Severe and Rare Disease, Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, 1 shuaifuyuan, Dongcheng District, Beijing, China.
| | - Huaiwu He
- State Key Laboratory of Complex Severe and Rare Disease, Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, 1 shuaifuyuan, Dongcheng District, Beijing, China.
| |
Collapse
|
17
|
Fazzini B, Page A, Pearse R, Puthucheary Z. Prone positioning for non-intubated spontaneously breathing patients with acute hypoxaemic respiratory failure: a systematic review and meta-analysis. Br J Anaesth 2022; 128:352-362. [PMID: 34774295 PMCID: PMC8514681 DOI: 10.1016/j.bja.2021.09.031] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/06/2021] [Accepted: 09/23/2021] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Prone positioning in non-intubated spontaneously breathing patients is becoming widely applied in practice alongside noninvasive respiratory support. This systematic review and meta-analysis evaluates the effect, timing, and populations that might benefit from awake proning regarding oxygenation, mortality, and tracheal intubation compared with supine position in hypoxaemic acute respiratory failure. METHODS We conducted a systematic literature search of PubMed/MEDLINE, Cochrane Library, Embase, CINAHL, and BMJ Best Practice until August 2021 (International Prospective Register of Systematic Reviews [PROSPERO] registration: CRD42021250322). Studies included comprise least-wise 20 adult patients with hypoxaemic respiratory failure secondary to acute respiratory distress syndrome or coronavirus disease (COVID-19). Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed, and study quality was assessed using the Newcastle-Ottawa Scale and the Cochrane risk-of-bias tool. RESULTS Fourteen studies fulfilled the selection criteria and 2352 patients were included; of those patients, 99% (n=2332/2352) had COVID-19. Amongst 1041 (44%) patients who were placed in the prone position, 1021 were SARS-CoV-2 positive. The meta-analysis revealed significant improvement in the PaO2/FiO2 ratio (mean difference -23.10; 95% confidence interval [CI]: -34.80 to 11.39; P=0.0001; I2=26%) after prone positioning. In patients with COVID-19, lower mortality was found in the group placed in the prone position (150/771 prone vs 391/1457 supine; odds ratio [OR] 0.51; 95% CI: 0.32-0.80; P=0.003; I2=48%), but the tracheal intubation rate was unchanged (284/824 prone vs 616/1271 supine; OR 0.72; 95% CI: 0.43-1.22; P=0.220; I2=75%). Overall proning was tolerated for a median of 4 h (inter-quartile range: 2-16). CONCLUSIONS Prone positioning can improve oxygenation amongst non-intubated patients with acute hypoxaemic respiratory failure when applied for at least 4 h over repeated daily episodes. Awake proning appears safe, but the effect on tracheal intubation rate and survival remains uncertain.
Collapse
Affiliation(s)
- Brigitta Fazzini
- Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, London, UK.
| | - Alexandria Page
- Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, London, UK
| | - Rupert Pearse
- Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, London, UK; William Harvey Research Institute, Queen Mary University of London, London, UK
| | - Zudin Puthucheary
- Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, London, UK; William Harvey Research Institute, Queen Mary University of London, London, UK
| |
Collapse
|
18
|
Postoperative pulmonale Komplikationen nach chirurgischen Eingriffen. ANÄSTHESIE NACHRICHTEN 2021. [PMCID: PMC8720644 DOI: 10.1007/s44179-021-0039-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
19
|
Chiumello D, Meli A, Pozzi T, Lucenteforte M, Simili P, Sterchele E, Coppola S. Different Inspiratory Flow Waveform during Volume-Controlled Ventilation in ARDS Patients. J Clin Med 2021; 10:jcm10204756. [PMID: 34682881 PMCID: PMC8540057 DOI: 10.3390/jcm10204756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/30/2021] [Accepted: 10/12/2021] [Indexed: 11/16/2022] Open
Abstract
The most used types of mechanical ventilation are volume- and pressure-controlled ventilation, respectively characterized by a square and a decelerating flow waveform. Nowadays, the clinical utility of different inspiratory flow waveforms remains unclear. The aim of this study was to assess the effects of four different inspiratory flow waveforms in ARDS patients. Twenty-eight ARDS patients (PaO2/FiO2 182 ± 40 and PEEP 11.3 ± 2.5 cmH2O) were ventilated in volume-controlled ventilation with four inspiratory flow waveforms: square (SQ), decelerating (DE), sinusoidal (SIN), and trunk descending (TDE). After 30 min in each condition, partitioned respiratory mechanics and gas exchange were collected. The inspiratory peak flow was higher in the DE waveform compared to the other three waveforms, and in SIN compared to the SQ and TDE waveforms, respectively. The mean inspiratory flow was higher in the DE and SIN waveforms compared with TDE and SQ. The inspiratory peak pressure was higher in the SIN and SQ compared to the TDE waveform. Partitioned elastance was similar in the four groups; mechanical power was lower in the TDE waveform, while PaCO2 in DE. No major effect on oxygenation was found. The explored flow waveforms did not provide relevant changes in oxygenation and respiratory mechanics.
Collapse
Affiliation(s)
- Davide Chiumello
- Department of Anesthesia and Intensive Care, ASST Santi Paolo e Carlo, San Paolo University Hospital, Via Di Rudini 9, 20142 Milan, Italy;
- Department of Health Sciences, University of Milan, 20142 Milan, Italy; (T.P.); (M.L.); (P.S.); (E.S.)
- Coordinated Research Center on Respiratory Failure, University of Milan, 20142 Milan, Italy
- Correspondence:
| | - Andrea Meli
- Department of Anesthesia, Intensive Care and Emergency, Fondazione IRCCS Ca’ Granda Hospital Maggiore Policlinico, Via F. Sforza 35, 20122 Milan, Italy;
| | - Tommaso Pozzi
- Department of Health Sciences, University of Milan, 20142 Milan, Italy; (T.P.); (M.L.); (P.S.); (E.S.)
| | - Manuela Lucenteforte
- Department of Health Sciences, University of Milan, 20142 Milan, Italy; (T.P.); (M.L.); (P.S.); (E.S.)
| | - Paolo Simili
- Department of Health Sciences, University of Milan, 20142 Milan, Italy; (T.P.); (M.L.); (P.S.); (E.S.)
| | - Elda Sterchele
- Department of Health Sciences, University of Milan, 20142 Milan, Italy; (T.P.); (M.L.); (P.S.); (E.S.)
| | - Silvia Coppola
- Department of Anesthesia and Intensive Care, ASST Santi Paolo e Carlo, San Paolo University Hospital, Via Di Rudini 9, 20142 Milan, Italy;
| |
Collapse
|
20
|
Marongiu I, Spinelli E, Scotti E, Mazzucco A, Wang YM, Manesso L, Colussi G, Biancolilli O, Battistin M, Langer T, Roma F, Lopez G, Lonati C, Vaira V, Rosso L, Ferrero S, Gatti S, Zanella A, Pesenti A, Mauri T. Addition of 5% CO 2 to Inspiratory Gas Prevents Lung Injury in an Experimental Model of Pulmonary Artery Ligation. Am J Respir Crit Care Med 2021; 204:933-942. [PMID: 34252009 PMCID: PMC8534619 DOI: 10.1164/rccm.202101-0122oc] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 07/12/2021] [Indexed: 11/19/2022] Open
Abstract
Rationale: Unilateral ligation of the pulmonary artery may induce lung injury through multiple mechanisms, which might be dampened by inhaled CO2. Objectives: This study aims to characterize bilateral lung injury owing to unilateral ligation of the pulmonary artery in healthy swine undergoing controlled mechanical ventilation and its prevention by 5% CO2 inhalation and to investigate relevant pathophysiological mechanisms. Methods: Sixteen healthy pigs were allocated to surgical ligation of the left pulmonary artery (ligation group), seven to surgical ligation of the left pulmonary artery and inhalation of 5% CO2 (ligation + FiCO2 5%), and six to no intervention (no ligation). Then, all animals received mechanical ventilation with Vt 10 ml/kg, positive end-expiratory pressure 5 cm H2O, respiratory rate 25 breaths/min, and FiO2 50% (±FiCO2 5%) for 48 hours or until development of severe lung injury. Measurements and Main Results: Histological, physiological, and quantitative computed tomography scan data were compared between groups to characterize lung injury. Electrical impedance tomography and immunohistochemistry analysis were performed in a subset of animals to explore mechanisms of injury. Animals from the ligation group developed bilateral lung injury as assessed by significantly higher histological score, larger increase in lung weight, poorer oxygenation, and worse respiratory mechanics compared with the ligation + FiCO2 5% group. In the ligation group, the right lung received a larger fraction of Vt and inflammation was more represented, whereas CO2 dampened both processes. Conclusions: Mechanical ventilation induces bilateral lung injury within 48 hours in healthy pigs undergoing left pulmonary artery ligation. Inhalation of 5% CO2 prevents injury, likely through decreased stress to the right lung and antiinflammatory effects.
Collapse
Affiliation(s)
| | | | | | | | - Yu-Mei Wang
- Department of Anesthesia, Critical Care and Emergency
- Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; and
| | | | | | | | | | - Thomas Langer
- School of Medicine and Surgery, University of Milan–Bicocca, Niguarda Ca’ Granda Hospital, Milan, Italy
| | | | - Gianluca Lopez
- Department of Biomedical Surgical and Dental Sciences, University of Milan, Milan, Italy
- Division of Pathology, and
| | - Caterina Lonati
- Center for Preclinical Research, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Valentina Vaira
- Department of Pathophysiology and Transplantation
- Division of Pathology, and
| | | | - Stefano Ferrero
- Department of Biomedical Surgical and Dental Sciences, University of Milan, Milan, Italy
- Division of Pathology, and
| | - Stefano Gatti
- Center for Preclinical Research, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alberto Zanella
- Department of Pathophysiology and Transplantation
- Department of Anesthesia, Critical Care and Emergency
| | - Antonio Pesenti
- Department of Pathophysiology and Transplantation
- Department of Anesthesia, Critical Care and Emergency
| | - Tommaso Mauri
- Department of Pathophysiology and Transplantation
- Department of Anesthesia, Critical Care and Emergency
| |
Collapse
|
21
|
Battaglini D, Robba C, Ball L, Silva PL, Cruz FF, Pelosi P, Rocco PRM. Noninvasive respiratory support and patient self-inflicted lung injury in COVID-19: a narrative review. Br J Anaesth 2021; 127:353-364. [PMID: 34217468 PMCID: PMC8173496 DOI: 10.1016/j.bja.2021.05.024] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 04/17/2021] [Accepted: 05/16/2021] [Indexed: 12/20/2022] Open
Abstract
COVID-19 pneumonia is associated with hypoxaemic respiratory failure, ranging from mild to severe. Because of the worldwide shortage of ICU beds, a relatively high number of patients with respiratory failure are receiving prolonged noninvasive respiratory support, even when their clinical status would have required invasive mechanical ventilation. There are few experimental and clinical data reporting that vigorous breathing effort during spontaneous ventilation can worsen lung injury and cause a phenomenon that has been termed patient self-inflicted lung injury (P-SILI). The aim of this narrative review is to provide an overview of P-SILI pathophysiology and the role of noninvasive respiratory support in COVID-19 pneumonia. Respiratory mechanics, vascular compromise, viscoelastic properties, lung inhomogeneity, work of breathing, and oesophageal pressure swings are discussed. The concept of P-SILI has been widely investigated in recent years, but controversies persist regarding its mechanisms. To minimise the risk of P-SILI, intensivists should better understand its underlying pathophysiology to optimise the type of noninvasive respiratory support provided to patients with COVID-19 pneumonia, and decide on the optimal timing of intubation for these patients.
Collapse
Affiliation(s)
- Denise Battaglini
- Anesthesia and Intensive Care, San Martino Policlinico Hospital, IRCCS for Oncology and Neuroscience, Genoa, Italy; Department of Medicine, University of Barcelona, Barcelona, Spain
| | - Chiara Robba
- Anesthesia and Intensive Care, San Martino Policlinico Hospital, IRCCS for Oncology and Neuroscience, Genoa, Italy; Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
| | - Lorenzo Ball
- Anesthesia and Intensive Care, San Martino Policlinico Hospital, IRCCS for Oncology and Neuroscience, Genoa, Italy; Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
| | - Pedro L Silva
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; COVID-19 Virus Network, Ministry of Science, Technology, and Innovation, Brasilia, Brazil
| | - Fernanda F Cruz
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; COVID-19 Virus Network, Ministry of Science, Technology, and Innovation, Brasilia, Brazil
| | - Paolo Pelosi
- Anesthesia and Intensive Care, San Martino Policlinico Hospital, IRCCS for Oncology and Neuroscience, Genoa, Italy; Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
| | - Patricia R M Rocco
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; COVID-19 Virus Network, Ministry of Science, Technology, and Innovation, Brasilia, Brazil.
| |
Collapse
|
22
|
Kaczka DW. Oscillatory ventilation redux: alternative perspectives on ventilator-induced lung injury in the acute respiratory distress syndrome. CURRENT OPINION IN PHYSIOLOGY 2021; 21:36-43. [PMID: 33898903 PMCID: PMC8056876 DOI: 10.1016/j.cophys.2021.03.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
For patients with the acute respiratory distress syndrome (ARDS), ventilation strategies that limit end-expiratory derecruitment and end-inspiratory overdistension are the only interventions to have significantly reduced the morbidity and mortality. For this reason, the use of high-frequency oscillatory ventilation (HFOV) was considered to be an ideal protective strategy, given its reliance on very low tidal volumes cycled at very high rates. However, results from clinical trials in adults with ARDS have demonstrated that HFOV does not improve clinical outcomes. Recent experimental and computational studies have shown that oscillation of a mechanically heterogeneous lung with multiple simultaneous frequencies can reduce parenchymal strain, improve gas exchange, and maintain lung recruitment at lower distending pressures compared to traditional ‘single-frequency’ HFOV. This review will discuss the theoretical rationale for the use of multiple oscillatory frequencies in ARDS, as well as the mechanisms by which it may reduce the risk for ventilator-induced lung injury.
Collapse
Affiliation(s)
- David W Kaczka
- Department of Anesthesia, University of Iowa, Iowa City, IA, USA.,Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA.,Department of Radiology, University of Iowa, Iowa City, IA, USA
| |
Collapse
|
23
|
Yang L, Dai M, Möller K, Frerichs I, Adler A, Fu F, Zhao Z. Lung regions identified with CT improve the value of global inhomogeneity index measured with electrical impedance tomography. Quant Imaging Med Surg 2021; 11:1209-1219. [PMID: 33816161 DOI: 10.21037/qims-20-682] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background The global inhomogeneity (GI) index is a functional electrical impedance tomography (EIT) parameter which is used clinically to assess ventilation distribution. However, GI may underestimate the actual heterogeneity when the size of lung regions is underestimated. We propose a novel method to use anatomical information to correct the GI index calculation. Methods EIT measurements were performed at the level of the fifth intercostal space in six patients with acute respiratory distress syndrome. The thorax and lungs were segmented automatically from serial individual CT scans. The anatomically derived lung regions were calculated in EIT images from simulating a homogeneous ventilation distribution in a finite element model. The conventional approach (GImeas,func ), analyzes images in functionally-defined lung regions, while our proposed measure (GImeas,anat ) is based on analysis in anatomically-defined regions. We additionally define a simulated comparison (GIsim,anat ) to determine the lower limit of the GI measure for a homogenous distribution of ventilation. Results As expected, the conventional GImeas,func [0.382 (0.088), median (interquartile range)] were significantly lower than the proposed GImeas,anat [0.823 (0.152), P<0.05], and were much closer to the lower limit GIsim,anat [0.343 (0.039)]. Both GImeas,anat and GImeas,func were strongly correlated with arterial oxygen partial pressure to fractional inspired oxygen ratio (R=-0.88, P<0.05), whereas GIsim,anat (R=0.23) was not. GImeas,anat had a linear-regression slope 3.2 times that of GImeas,func suggesting a higher sensitivity to the changes in lung condition. Conclusions The proposed GImeas,anat (or shortened as GIanat ) is an improved measure of ventilation inhomogeneity over GI, and better reflects portion of non-ventilated regions due to alveolar collapse or overdistension.
Collapse
Affiliation(s)
- Lin Yang
- Department of Aerospace Medicine, Fourth Military Medical University, Xi'an, China
| | - Meng Dai
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Knut Möller
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
| | - Inéz Frerichs
- Department of Anaesthesiology and Intensive Care Medicine, University Medical Centre of Schleswig-Holstein Campus Kiel, Germany
| | - Andy Adler
- Department of Systems and Computer Engineering, Carleton University, Ottawa, Canada
| | - Feng Fu
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Zhanqi Zhao
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China.,Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
| |
Collapse
|
24
|
Pellegrini M, Hedenstierna G, Larsson AS, Perchiazzi G. Inspiratory Efforts, Positive End-Expiratory Pressure, and External Resistances Influence Intraparenchymal Gas Redistribution in Mechanically Ventilated Injured Lungs. Front Physiol 2021; 11:618640. [PMID: 33633578 PMCID: PMC7900494 DOI: 10.3389/fphys.2020.618640] [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] [Received: 10/17/2020] [Accepted: 12/22/2020] [Indexed: 12/18/2022] Open
Abstract
Background Potentially harmful lung overstretch can follow intraparenchymal gas redistribution during mechanical ventilation. We hypothesized that inspiratory efforts characterizing spontaneous breathing, positive end-expiratory pressure (PEEP), and high inspiratory resistances influence inspiratory intraparenchymal gas redistribution. Methods This was an experimental study conducted on a swine model of mild acute respiratory distress syndrome. Dynamic computed tomography and respiratory mechanics were simultaneously acquired at different PEEP levels and external resistances, during both spontaneous breathing and controlled mechanical ventilation. Images were collected at two cranial-caudal levels. Delta-volume images (ΔVOLs) were obtained subtracting pairs of consecutive inspiratory images. The first three ΔVOLs, acquired for each analyzed breath, were used for the analysis of inspiratory pendelluft defined as intraparenchymal gas redistribution before the start of inspiratory flow at the airway opening. The following ΔVOLs were used for the analysis of gas redistribution during ongoing inspiratory flow at the airway opening. Results During the first flow-independent phase of inspiration, the pendelluft of gas was observed only during spontaneous breathing and along the cranial-to-caudal and nondependent-to-dependent directions. The pendelluft was reduced by high PEEP (p < 0.04 comparing PEEP 15 and PEEP 0 cm H2O) and low external resistances (p < 0.04 comparing high and low external resistance). During the flow-dependent phase of inspiration, two patterns were identified: (1) gas displacing characterized by large gas redistribution areas; (2) gas scattering characterized by small, numerous areas of gas redistribution. Gas displacing was observed at low PEEP, high external resistances, and it characterized controlled mechanical ventilation (p < 0.01, comparing high and low PEEP during controlled mechanical ventilation). Conclusions Low PEEP and high external resistances favored inspiratory pendelluft. During the flow-dependent phase of the inspiration, controlled mechanical ventilation and low PEEP and high external resistances favored larger phenomena of intraparenchymal gas redistribution (gas displacing) endangering lung stability.
Collapse
Affiliation(s)
- Mariangela Pellegrini
- Hedenstierna Laboratory, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.,Intensive Care Unit, Department of Anesthesia, Operation and Intensive Care, Uppsala University Hospital, Uppsala, Sweden
| | - Göran Hedenstierna
- Hedenstierna Laboratory, Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Anders Sune Larsson
- Hedenstierna Laboratory, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Gaetano Perchiazzi
- Hedenstierna Laboratory, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.,Intensive Care Unit, Department of Anesthesia, Operation and Intensive Care, Uppsala University Hospital, Uppsala, Sweden
| |
Collapse
|
25
|
Sang L, Zhao Z, Yun PJ, Frerichs I, Möller K, Fu F, Liu X, Zhong N, Li Y. Qualitative and quantitative assessment of pendelluft: a simple method based on electrical impedance tomography. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:1216. [PMID: 33178748 PMCID: PMC7607126 DOI: 10.21037/atm-20-4182] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Background Pendelluft, defined as asynchronous alveolar ventilation, is caused by different regional time constants or dynamic pleural pressure variations. The aim of the present study was to propose a simple method to evaluate pendelluft based on electrical impedance tomography (EIT). The efficacy of this method was demonstrated in well-known pendelluft scenarios in 6 patients. Methods Two patients with flail chest after accidents, two patients with acute respiratory distress syndrome (ARDS) and two patients with acutely exacerbated obstructive lung disease were prospectively included. EIT measurements were performed before and after surgery (in patients with flail chest, who had video-assisted thoracoscopic surgery with ribs fixation), or at two different levels of positive end-expiratory pressure (PEEP; ARDS patients), or two different time points (obstructive lung disease). Pendelluft was assessed by regional phase shift (defined as time difference between global and regional impedance-time curves) and amplitude differences (defined as the impedance difference between sum of all regional tidal variation and the global tidal variation). Results In patients with flail chest, pendelluft diminished several days after surgery (pendelluft amplitude normalized to tidal impedance variation reduced from 88% to 2% in one patient, 12% to 2% in the other). Increased PEEP reduced the amplitude of pendelluft (from 3% to 0% in one patient, 20% to 2% in the other) but not necessarily the phase shifts (average time differences were <0.1 second for both patients for both ins- and expiration) in ARDS patients. Pendelluft assessment in obstructive lung diseases reflected the change in airway resistance (from 5% to 1% in one patient after broncholytic medication administration, as airway resistance fell from 15 to 11 cmH2O/L/s; from 9% to 35% in the other patient with acute exacerbation, the corresponding airway resistance increased from 15 to 22 cmH2O/L/s). Conclusions The proposed EIT-based method can be used to evaluate the degree of pendelluft in dimension of phase shift and amplitude difference.
Collapse
Affiliation(s)
- Ling Sang
- Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Guangzhou, China
| | - Zhanqi Zhao
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China.,Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
| | - Po-Jen Yun
- Division of Thoracic Surgery, Department of Surgery, Tri-Service General Hospital, Taipei
| | - Inéz Frerichs
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center of Schleswig-Holstein Campus Kiel, Kiel, Germany
| | - Knut Möller
- Institute of Technical Medicine, Furtwangen University, Villingen-Schwenningen, Germany
| | - Feng Fu
- Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China
| | - Xiaoqing Liu
- Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Guangzhou, China
| | - Nanshan Zhong
- Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Guangzhou, China
| | - Yimin Li
- Department of Critical Care Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, State Key Lab of Respiratory Diseases, Guangzhou Institute of Respiratory Health, Guangzhou, China
| |
Collapse
|
26
|
Hurtado DE, Erranz B, Lillo F, Sarabia-Vallejos M, Iturrieta P, Morales F, Blaha K, Medina T, Diaz F, Cruces P. Progression of regional lung strain and heterogeneity in lung injury: assessing the evolution under spontaneous breathing and mechanical ventilation. Ann Intensive Care 2020; 10:107. [PMID: 32761387 PMCID: PMC7407426 DOI: 10.1186/s13613-020-00725-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 07/30/2020] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Protective mechanical ventilation (MV) aims at limiting global lung deformation and has been associated with better clinical outcomes in acute respiratory distress syndrome (ARDS) patients. In ARDS lungs without MV support, the mechanisms and evolution of lung tissue deformation remain understudied. In this work, we quantify the progression and heterogeneity of regional strain in injured lungs under spontaneous breathing and under MV. METHODS Lung injury was induced by lung lavage in murine subjects, followed by 3 h of spontaneous breathing (SB-group) or 3 h of low Vt mechanical ventilation (MV-group). Micro-CT images were acquired in all subjects at the beginning and at the end of the ventilation stage following induction of lung injury. Regional strain, strain progression and strain heterogeneity were computed from image-based biomechanical analysis. Three-dimensional regional strain maps were constructed, from which a region-of-interest (ROI) analysis was performed for the regional strain, the strain progression, and the strain heterogeneity. RESULTS After 3 h of ventilation, regional strain levels were significantly higher in 43.7% of the ROIs in the SB-group. Significant increase in regional strain was found in 1.2% of the ROIs in the MV-group. Progression of regional strain was found in 100% of the ROIs in the SB-group, whereas the MV-group displayed strain progression in 1.2% of the ROIs. Progression in regional strain heterogeneity was found in 23.4% of the ROIs in the SB-group, while the MV-group resulted in 4.7% of the ROIs showing significant changes. Deformation progression is concurrent with an increase of non-aerated compartment in SB-group (from 13.3% ± 1.6% to 37.5% ± 3.1%), being higher in ventral regions of the lung. CONCLUSIONS Spontaneous breathing in lung injury promotes regional strain and strain heterogeneity progression. In contrast, low Vt MV prevents regional strain and heterogeneity progression in injured lungs.
Collapse
Affiliation(s)
- Daniel E Hurtado
- Department of Structural and Geotechnical Engineering, School of Engineering Pontificia, Universidad Católica de Chile, Santiago, Chile.,Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Millennium Nucleus for Cardiovascular Magnetic Resonance, Santiago, Chile
| | - Benjamín Erranz
- Centro de Medicina Regenerativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Felipe Lillo
- Centro de Investigación de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Mauricio Sarabia-Vallejos
- Department of Structural and Geotechnical Engineering, School of Engineering Pontificia, Universidad Católica de Chile, Santiago, Chile
| | - Pablo Iturrieta
- Department of Structural and Geotechnical Engineering, School of Engineering Pontificia, Universidad Católica de Chile, Santiago, Chile
| | - Felipe Morales
- Centro de Investigación de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Katherine Blaha
- Pediatric Critical Care Unit, Clínica Alemana de Santiago, Santiago, Chile
| | - Tania Medina
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Franco Diaz
- Centro de Medicina Regenerativa, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Pediatric Critical Care Unit, Clínica Alemana de Santiago, Santiago, Chile
| | - Pablo Cruces
- Centro de Investigación de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile. .,Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile.
| |
Collapse
|