1
|
Leali M, Marongiu I, Spinelli E, Chiavieri V, Perez J, Panigada M, Grasselli G, Mauri T. Absolute values of regional ventilation-perfusion mismatch in patients with ARDS monitored by electrical impedance tomography and the role of dead space and shunt compensation. Crit Care 2024; 28:241. [PMID: 39010228 PMCID: PMC11251389 DOI: 10.1186/s13054-024-05033-8] [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: 04/15/2024] [Accepted: 07/11/2024] [Indexed: 07/17/2024] Open
Abstract
BACKGROUND Assessment of regional ventilation/perfusion (V'/Q) mismatch using electrical impedance tomography (EIT) represents a promising advancement for personalized management of the acute respiratory distress syndrome (ARDS). However, accuracy is still hindered by the need for invasive monitoring to calibrate ventilation and perfusion. Here, we propose a non-invasive correction that uses only EIT data and characterized patients with more pronounced compensation of V'/Q mismatch. METHODS We enrolled twenty-one ARDS patients on controlled mechanical ventilation. Cardiac output was measured invasively, and ventilation and perfusion were assessed by EIT. Relative V'/Q maps by EIT were calibrated to absolute values using the minute ventilation to invasive cardiac output (MV/CO) ratio (V'/Q-ABS), left unadjusted (V'/Q-REL), or corrected by MV/CO ratio derived from EIT data (V'/Q-CORR). The ratio between ventilation to dependent regions and perfusion reaching shunted units ( V D ' /QSHUNT) was calculated as an index of more effective hypoxic pulmonary vasoconstriction. The ratio between perfusion to non-dependent regions and ventilation to dead space units (QND/ V DS ' ) was calculated as an index of hypocapnic pneumoconstriction. RESULTS Our calibration factor correlated with invasive MV/CO (r = 0.65, p < 0.001), showed good accuracy and no apparent bias. Compared to V'/Q-ABS, V'/Q-REL maps overestimated ventilation (p = 0.013) and perfusion (p = 0.002) to low V'/Q units and underestimated ventilation (p = 0.011) and perfusion (p = 0.008) to high V'/Q units. The heterogeneity of ventilation and perfusion reaching different V'/Q compartments was underestimated. V'/Q-CORR maps eliminated all these differences with V'/Q-ABS (p > 0.05). HigherV D ' / Q SHUNT correlated with higher PaO2/FiO2 (r = 0.49, p = 0.025) and lower shunt fraction (ρ = - 0.59, p = 0.005). HigherQ ND / V DS ' correlated with lower PEEP (ρ = - 0.62, p = 0.003) and plateau pressure (ρ = - 0.59, p = 0.005). Lower values of both indexes were associated with less ventilator-free days (p = 0.05 and p = 0.03, respectively). CONCLUSIONS Regional V'/Q maps calibrated with a non-invasive EIT-only method closely approximate the ones obtained with invasive monitoring. Higher efficiency of shunt compensation improves oxygenation while compensation of dead space is less needed at lower airway pressure. Patients with more effective compensation mechanisms could have better outcomes.
Collapse
Affiliation(s)
- Marco Leali
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Ines Marongiu
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Elena Spinelli
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Valentina Chiavieri
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Joaquin Perez
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Mauro Panigada
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Giacomo Grasselli
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Tommaso Mauri
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
| |
Collapse
|
2
|
Spinelli E, Damia A, Damarco F, Gregori B, Occhipinti F, Busani Z, Leali M, Battistin M, Lonati C, Zhao Z, Storaci AM, Lopez G, Vaira V, Ferrero S, Rosso L, Gatti S, Mauri T. Pathophysiological profile of non-ventilated lung injury in healthy female pigs undergoing mechanical ventilation. COMMUNICATIONS MEDICINE 2024; 4:18. [PMID: 38361130 PMCID: PMC10869686 DOI: 10.1038/s43856-024-00449-3] [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: 08/23/2023] [Accepted: 02/01/2024] [Indexed: 02/17/2024] Open
Abstract
BACKGROUND Lung regions excluded from mechanical insufflation are traditionally assumed to be spared from ventilation-associated lung injury. However, preliminary data showed activation of potential mechanisms of injury within these non-ventilated regions (e.g., hypoperfusion, inflammation). METHODS In the present study, we hypothesized that non-ventilated lung injury (NVLI) may develop within 24 h of unilateral mechanical ventilation in previously healthy pigs, and we performed extended pathophysiological measures to profile NVLI. We included two experimental groups undergoing exclusion of the left lung from the ventilation with two different tidal volumes (15 vs 7.5 ml/kg) and a control group on bilateral ventilation. Pathophysiological alteration including lung collapse, changes in lung perfusion, lung stress and inflammation were measured. Lung injury was quantified by histological score. RESULTS Histological injury score of the non-ventilated lung is significantly higher than normally expanded lung from control animals. The histological score showed lower intermediate values (but still higher than controls) when the tidal volume distending the ventilated lung was reduced by 50%. Main pathophysiological alterations associated with NVLI were: extensive lung collapse; very low pulmonary perfusion; high inspiratory airways pressure; and higher concentrations of acute-phase inflammatory cytokines IL-6, IL-1β and TNF-α and of Angiopoietin-2 (a marker of endothelial activation) in the broncho-alveolar lavage. Only the last two alterations were mitigated by reducing tidal volume, potentially explaining partial protection. CONCLUSIONS Non-ventilated lung injury develops within 24 h of controlled mechanical ventilation due to multiple pathophysiological alterations, which are only partially prevented by low tidal volume.
Collapse
Grants
- This study was supported, in part, by Current Research from the Italian Ministry of Health, Rome, Italy; by EuroELSO Research grant 2021; by the “Hub Life Science-Diagnostica Avanzata (HLS-DA), PNC-E3-2022-23683266-CUP: C43C22001630001/MI-0117” Project from the Italian Ministry of Health (Piano Nazionale Complementare Ecosistema Innovativo della Salute), Rome, Italy; by the “Dipartimenti di Eccellenza Program 2023–2027” to the Dept. of Pathophysiology and Transplantation, University of Milan, from The Italian Ministry of Education and Research (MUR), Rome, Italy.
Collapse
Affiliation(s)
- Elena Spinelli
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Anna Damia
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Francesco Damarco
- Division of Thoracic Surgery and Lung Transplantation, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Beatrice Gregori
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Federica Occhipinti
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Zara Busani
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Marco Leali
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Michele Battistin
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Caterina Lonati
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Zhanqi Zhao
- Furtwangen University, Institute of Technical Medicine, Villingen-Schwenningen, Germany
| | - Alessandra Maria Storaci
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Gianluca Lopez
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Valentina Vaira
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefano Ferrero
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Biomedical Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Lorenzo Rosso
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Division of Thoracic Surgery and Lung Transplantation, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefano Gatti
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Tommaso Mauri
- Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.
| |
Collapse
|
3
|
Pérez J. Patient Self-Inflicted and Ventilator-induced Lung Injury: Two Sides of the Same Coin? Am J Respir Crit Care Med 2023; 207:1406-1407. [PMID: 36952680 PMCID: PMC10595450 DOI: 10.1164/rccm.202302-0257le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Affiliation(s)
- Joaquin Pérez
- Intensive Care Unit, Sanatorio Anchorena San Martín, Buenos Aires, Argentina and
- Emergency Department, Hospital Carlos G. Durand, Autonomous City of Buenos Aires, Argentina
| |
Collapse
|
4
|
Maamar A, Delamaire F, Reizine F, Lesouhaitier M, Painvin B, Quelven Q, Coirier V, Guillot P, Tulzo YL, Tadié JM, Gacouin A. Impact of Arterial CO 2 Retention in Patients With Moderate or Severe ARDS. Respir Care 2023; 68:582-591. [PMID: 36977590 PMCID: PMC10171350 DOI: 10.4187/respcare.10507] [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: 03/30/2023]
Abstract
BACKGROUND Lung-protective ventilation (reduced tidal volume and limited plateau pressure) may lead to CO2 retention. Data about the impact of hypercapnia in patients with ARDS are scarce and conflicting. METHODS We performed a non-interventional cohort study with subjects with ARDS admitted from 2006 to 2021 and with PaO2 /FIO2 ≤ 150 mm Hg. We examined the association between severe hypercapnia (PaCO2 ≥ 50 mm Hg) on the first 5 days after the diagnosis of ARDS and death in ICU for 930 subjects. All the subjects received lung-protective ventilation. RESULTS Severe hypercapnia was noted in 552 subjects (59%) on the first day of ARDS (day 1); 323/930 (34.7%) died in the ICU. Severe hypercapnia on day 1 was associated with mortality in the unadjusted (odds ratio 1.54, 95% CI 1.16-1.63; P = .003) and adjusted (odds ratio 1.47, 95% CI 1.08-2.43; P = .004) models. In the Bayesian analysis, the posterior probability that severe hypercapnia was associated with ICU death was > 90% in 4 different priors, including a septic prior for this association. Sustained severe hypercapnia on day 5, defined as severe hypercapnia present from day 1 to day 5, was noted in 93 subjects (12%). After propensity score matching, severe hypercapnia on day 5 remained associated with ICU mortality (odds ratio 1.73, 95% CI 1.02-2.97; P = .047). CONCLUSIONS Severe hypercapnia was associated with mortality in subjects with ARDS who received lung-protective ventilation. Our results deserve further evaluation of the strategies and treatments that aim to control CO2 retention.
Collapse
Affiliation(s)
- Adel Maamar
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
| | - Flora Delamaire
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
| | - Florian Reizine
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
- Inserm-CIC-1414, Faculté de Médecine, Université Rennes I, Rennes, France
| | - Mathieu Lesouhaitier
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
- Inserm-CIC-1414, Faculté de Médecine, Université Rennes I, Rennes, France
| | - Benoit Painvin
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
| | - Quentin Quelven
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
| | - Valentin Coirier
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
| | - Pauline Guillot
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
| | - Yves Le Tulzo
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
- Inserm-CIC-1414, Faculté de Médecine, Université Rennes I, Rennes, France
| | - Jean Marc Tadié
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
- Inserm-CIC-1414, Faculté de Médecine, Université Rennes I, Rennes, France
| | - Arnaud Gacouin
- Centre Hospitalier Universitaire Rennes, Maladies Infectieuses et Réanimation Médicale, Rennes, France.
- Université Rennes1, Faculté de Médecine, Biosit, Rennes, France
- Inserm-CIC-1414, Faculté de Médecine, Université Rennes I, Rennes, France
| |
Collapse
|
5
|
Zhang R, Chen H, Teng R, Li Z, Yang Y, Qiu H, Liu L. Association between the time-varying arterial carbon dioxide pressure and 28-day mortality in mechanically ventilated patients with acute respiratory distress syndrome. BMC Pulm Med 2023; 23:129. [PMID: 37076846 PMCID: PMC10113995 DOI: 10.1186/s12890-023-02431-6] [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: 11/28/2022] [Accepted: 04/13/2023] [Indexed: 04/21/2023] Open
Abstract
BACKGROUND Recent studies have shown an association between baseline arterial carbon dioxide pressure (PaCO2) and outcomes in patients with acute respiratory distress syndrome (ARDS). However, PaCO2 probably varies throughout the disease, and few studies have assessed the effect of longitudinal PaCO2 on prognosis. We thus aimed to investigate the association between time-varying PaCO2 and 28-day mortality in mechanically ventilated ARDS patients. METHODS In this retrospective study, we included all adult (≥ 18 years) patients diagnosed with ARDS who received mechanical ventilation for at least 24 h at a tertiary teaching hospital between January 2014 and March 2021. Patients were excluded if they received extracorporeal membrane oxygenation (ECMO). Demographic data, respiratory variables, and daily PaCO2 were extracted. The primary outcome was 28-day mortality. Time-varying Cox models were used to estimate the association between longitudinal PaCO2 measurements and 28-day mortality. RESULTS A total of 709 patients were eligible for inclusion in the final cohort, with an average age of 65 years, of whom 70.7% were male, and the overall 28-day mortality was 35.5%. After adjustment for baseline confounders, including age and severity of disease, a significant increase in the hazard of death was found to be associated with both time-varying PaCO2 (HR 1.07, 95% CI 1.03-1.11, p<0.001) and the time-varying coefficient of variation for PaCO2 (HR 1.24 per 10% increase, 95% CI 1.10-1.40, p<0.001) during the first five days of invasive mechanical ventilation. The cumulative proportion of exposure to normal PaCO2 (HR 0.72 per 10% increase, 95% CI 0.58-0.89, p = 0.002) was associated with 28-day mortality. CONCLUSION PaCO2 should be closely monitored in mechanically ventilated ARDS patients. The association between PaCO2 and 28-day mortality persisted over time. Increased cumulative exposure to normal PaCO2 was associated with a decreased risk of death.
Collapse
Affiliation(s)
- Rui Zhang
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, 210009, China
| | - Hui Chen
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, 210009, China
- Department of Critical Care Medicine, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215000, China
| | - Ran Teng
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, 210009, China
| | - Zuxian Li
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, 210009, China
| | - Yi Yang
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, 210009, China
| | - Haibo Qiu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, 210009, China
| | - Ling Liu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Critical Care Medicine, School of Medicine, Zhongda Hospital, Southeast University, Nanjing, Jiangsu, 210009, China.
| |
Collapse
|
6
|
Slobod D, Damia A, Leali M, Spinelli E, Mauri T. Pathophysiology and Clinical Meaning of Ventilation-Perfusion Mismatch in the Acute Respiratory Distress Syndrome. BIOLOGY 2022; 12:biology12010067. [PMID: 36671759 PMCID: PMC9855693 DOI: 10.3390/biology12010067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/20/2022] [Accepted: 12/27/2022] [Indexed: 01/03/2023]
Abstract
Acute respiratory distress syndrome (ARDS) remains an important clinical challenge with a mortality rate of 35-45%. It is being increasingly demonstrated that the improvement of outcomes requires a tailored, individualized approach to therapy, guided by a detailed understanding of each patient's pathophysiology. In patients with ARDS, disturbances in the physiological matching of alveolar ventilation (V) and pulmonary perfusion (Q) (V/Q mismatch) are a hallmark derangement. The perfusion of collapsed or consolidated lung units gives rise to intrapulmonary shunting and arterial hypoxemia, whereas the ventilation of non-perfused lung zones increases physiological dead-space, which potentially necessitates increased ventilation to avoid hypercapnia. Beyond its impact on gas exchange, V/Q mismatch is a predictor of adverse outcomes in patients with ARDS; more recently, its role in ventilation-induced lung injury and worsening lung edema has been described. Innovations in bedside imaging technologies such as electrical impedance tomography readily allow clinicians to determine the regional distributions of V and Q, as well as the adequacy of their matching, providing new insights into the phenotyping, prognostication, and clinical management of patients with ARDS. The purpose of this review is to discuss the pathophysiology, identification, consequences, and treatment of V/Q mismatch in the setting of ARDS, employing experimental data from clinical and preclinical studies as support.
Collapse
Affiliation(s)
- Douglas Slobod
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Critical Care Medicine, McGill University, Montreal, QC H3A 3R1, Canada
| | - Anna Damia
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
| | - Marco Leali
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
| | - Elena Spinelli
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Tommaso Mauri
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Ca’ Granda, Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
- Correspondence:
| |
Collapse
|
7
|
Pavlovsky B, Pesenti A, Spinelli E, Scaramuzzo G, Marongiu I, Tagliabue P, Spadaro S, Grasselli G, Mercat A, Mauri T. Effects of PEEP on regional ventilation-perfusion mismatch in the acute respiratory distress syndrome. Crit Care 2022; 26:211. [PMID: 35818077 PMCID: PMC9272883 DOI: 10.1186/s13054-022-04085-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 07/05/2022] [Indexed: 11/10/2022] Open
Abstract
Purpose In the acute respiratory distress syndrome (ARDS), decreasing Ventilation-Perfusion \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\left( {{{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}} \right)$$\end{document}V˙/Q˙ mismatch might enhance lung protection. We investigated the regional effects of higher Positive End Expiratory Pressure (PEEP) on \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ mismatch and their correlation with recruitability. We aimed to verify whether PEEP improves regional \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ mismatch, and to study the underlying mechanisms. Methods In fifteen patients with moderate and severe ARDS, two PEEP levels (5 and 15 cmH2O) were applied in random order. \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ mismatch was assessed by Electrical Impedance Tomography at each PEEP. Percentage of ventilation and perfusion reaching different ranges of \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ ratios were analyzed in 3 gravitational lung regions, leading to precise assessment of their distribution throughout different \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ mismatch compartments. Recruitability between the two PEEP levels was measured by the recruitment-to-inflation ratio method. Results In the non-dependent region, at higher PEEP, ventilation reaching the normal \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ compartment (p = 0.018) increased, while it decreased in the high \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ one (p = 0.023). In the middle region, at PEEP 15 cmH2O, ventilation and perfusion to the low \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ compartment decreased (p = 0.006 and p = 0.011) and perfusion to normal \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ increased (p = 0.003). In the dependent lung, the percentage of blood flowing through the non-ventilated compartment decreased (p = 0.041). Regional \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ mismatch improvement was correlated to lung recruitability and changes in regional tidal volume. Conclusions In patients with ARDS, higher PEEP optimizes the distribution of both ventilation (in the non-dependent areas) and perfusion (in the middle and dependent lung). Bedside measure of recruitability is associated with improved \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${{\dot{V}} \mathord{\left/ {\vphantom {{\dot{V}} {\dot{Q}}}} \right. \kern-\nulldelimiterspace} {\dot{Q}}}$$\end{document}V˙/Q˙ mismatch. Supplementary Information The online version contains supplementary material available at 10.1186/s13054-022-04085-y.
Collapse
|
8
|
Teijeiro-Paradis R, Pesenti A, Fan E. Weaning from Veno-Venous ECMO: Lessons from 60 Years of Weaning from Mechanical Ventilation. Am J Respir Crit Care Med 2022; 206:928-930. [PMID: 35727205 PMCID: PMC9802004 DOI: 10.1164/rccm.202206-1104ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Ricardo Teijeiro-Paradis
- Interdepartmental Division of Critical Care MedicineUniversity of TorontoToronto, Ontario, Canada
| | - Antonio Pesenti
- Dipartimento di Anestesia, Rianimazione e Emergenza-Urgenza,Fondazione IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico)Ca’ Granda Ospedale Maggiore PoliclinicoMilan, Italy,Department of Pathophysiology and TransplantationUniversity of MilanMilan, Italy
| | - Eddy Fan
- Interdepartmental Division of Critical Care MedicineUniversity of TorontoToronto, Ontario, Canada,Institute of Health Policy Management and EvaluationUniversity of TorontoToronto, Ontario, Canada
| |
Collapse
|
9
|
Spinelli E, Pesenti A, Lopez G, Damia A, Damarco F, Garbelli E, Dal Santo G, Caccioppola A, Giudici G, Figgiaconi V, Biancolilli O, Battistin M, Lonati C, Vaira V, Rosso L, Ferrero S, Gatti S, Mauri T. Inhaled CO2 vs. Hypercapnia Obtained by Low Tidal Volume or Instrumental Dead Space in Unilateral Pulmonary Artery Ligation: Any Difference for Lung Protection? Front Med (Lausanne) 2022; 9:901809. [PMID: 35669918 PMCID: PMC9163369 DOI: 10.3389/fmed.2022.901809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 04/19/2022] [Indexed: 11/20/2022] Open
Abstract
Background Unilateral ligation of the pulmonary artery (UPAL) induces bilateral lung injury in pigs undergoing controlled mechanical ventilation. Possible mechanisms include redistribution of ventilation toward the non-ligated lung and hypoperfusion of the ligated lung. The addition of 5% CO2 to the inspiratory gas (FiCO2) prevents the injury, but it is not clear whether lung protection is a direct effect of CO2 inhalation or it is mediated by plasmatic hypercapnia. This study aims to compare the effects and mechanisms of FiCO2vs. hypercapnia induced by low tidal volume ventilation or instrumental dead space. Methods Healthy pigs underwent left UPAL and were allocated for 48 h to the following: Volume-controlled ventilation (VCV) with VT 10 ml/kg (injury, n = 6); VCV plus 5% FiCO2 (FiCO2, n = 7); VCV with VT 6 ml/kg (low VT, n = 6); VCV plus additional circuit dead space (instrumental VD, n = 6). Histological score, regional compliance, wet-to-dry ratio, and inflammatory infiltrate were assessed to evaluate lung injury at the end of the study. To investigate the mechanisms of protection, we quantified the redistribution of ventilation to the non-ligated lung, as the ratio between the percentage of tidal volume to the right and to the left lung (VTRIGHT/LEFT), and the hypoperfusion of the ligated lung as the percentage of blood flow reaching the left lung (PerfusionLEFT). Results In the left ligated lung, injury was prevented only in the FiCO2 group, as indicated by lower histological score, higher regional compliance, lower wet-to-dry ratio and lower density of inflammatory cells compared to other groups. For the right lung, the histological score was lower both in the FiCO2 and in the low VT groups, but the other measures of injury showed lower intensity only in the FiCO2 group. VTRIGHT/LEFT was lower and PerfusionLEFT was higher in the FiCO2 group compared to other groups. Conclusion In a model of UPAL, inhaled CO2 but not hypercapnia grants bilateral lung protection. Mechanisms of protection include reduced overdistension of the non-ligated and increased perfusion of the ligated lung.
Collapse
Affiliation(s)
- Elena Spinelli
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Antonio Pesenti
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Gianluca Lopez
- Department of Biomedical Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Anna Damia
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Francesco Damarco
- Division of Thoracic Surgery and Lung Transplantation, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Erica Garbelli
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Gaia Dal Santo
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Alessio Caccioppola
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Giorgio Giudici
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Virginia Figgiaconi
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Osvaldo Biancolilli
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Michele Battistin
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Caterina Lonati
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Valentina Vaira
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Lorenzo Rosso
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- Division of Thoracic Surgery and Lung Transplantation, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefano Ferrero
- Department of Biomedical Surgical and Dental Sciences, University of Milan, Milan, Italy
- Division of Pathology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Stefano Gatti
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
| | - Tommaso Mauri
- Department of Anesthesia, Critical Care and Emergency, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
- *Correspondence: Tommaso Mauri
| |
Collapse
|
10
|
Ismaiel N, Whynot S, Geldenhuys L, Xu Z, Slutsky AS, Chappe V, Henzler D. Lung-Protective Ventilation Attenuates Mechanical Injury While Hypercapnia Attenuates Biological Injury in a Rat Model of Ventilator-Associated Lung Injury. Front Physiol 2022; 13:814968. [PMID: 35530505 PMCID: PMC9068936 DOI: 10.3389/fphys.2022.814968] [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: 11/14/2021] [Accepted: 03/21/2022] [Indexed: 12/30/2022] Open
Abstract
Background and Objective: Lung-protective mechanical ventilation is known to attenuate ventilator-associated lung injury (VALI), but often at the expense of hypoventilation and hypercapnia. It remains unclear whether the main mechanism by which VALI is attenuated is a product of limiting mechanical forces to the lung during ventilation, or a direct biological effect of hypercapnia. Methods: Acute lung injury (ALI) was induced in 60 anesthetized rats by the instillation of 1.25 M HCl into the lungs via tracheostomy. Ten rats each were randomly assigned to one of six experimental groups and ventilated for 4 h with: 1) Conventional HighVENormocapnia (high VT, high minute ventilation, normocapnia), 2) Conventional Normocapnia (high VT, normocapnia), 3) Protective Normocapnia (VT 8 ml/kg, high RR), 4) Conventional iCO2Hypercapnia (high VT, low RR, inhaled CO2), 5) Protective iCO2Hypercapnia (VT 8 ml/kg, high RR, added CO2), 6) Protective endogenous Hypercapnia (VT 8 ml/kg, low RR). Blood gasses, broncho-alveolar lavage fluid (BALF), and tissue specimens were collected and analyzed for histologic and biologic lung injury assessment. Results: Mild ALI was achieved in all groups characterized by a decreased mean PaO2/FiO2 ratio from 428 to 242 mmHg (p < 0.05), and an increased mean elastance from 2.46 to 4.32 cmH2O/L (p < 0.0001). There were no differences in gas exchange among groups. Wet-to-dry ratios and formation of hyaline membranes were significantly lower in low VT groups compared to conventional tidal volumes. Hypercapnia reduced diffuse alveolar damage and IL-6 levels in the BALF, which was also true when CO2 was added to conventional VT. In low VT groups, hypercapnia did not induce any further protective effect except increasing pulmonary IL-10 in the BALF. No differences in lung injury were observed when hypercapnia was induced by adding CO2 or decreasing minute ventilation, although permissive hypercapnia decreased the pH significantly and decreased liver histologic injury. Conclusion: Our findings suggest that low tidal volume ventilation likely attenuates VALI by limiting mechanical damage to the lung, while hypercapnia attenuates VALI by limiting pro-inflammatory and biochemical mechanisms of injury. When combined, both lung-protective ventilation and hypercapnia have the potential to exert an synergistic effect for the prevention of VALI.
Collapse
Affiliation(s)
- Nada Ismaiel
- Faculty of Medicine, Dalhousie University, Halifax, NS, Canada.,Department of Anesthesia, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Sara Whynot
- Department of Anesthesia, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Laurette Geldenhuys
- Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Zhaolin Xu
- Department of Pathology, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | | | - Valerie Chappe
- Department of Physiology and Biophysics, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada
| | - Dietrich Henzler
- Department of Anesthesia, Faculty of Medicine, Dalhousie University, Halifax, NS, Canada.,Department of Anesthesiology, Medical Faculty, Ruhr University Bochum, Bochum, Germany
| |
Collapse
|
11
|
Spinelli E, Mauri T. Reply to: Addition of 5% CO2 to Inspiratory Gas in Preventing Lung Injury Due to Pulmonary Artery Ligation. Am J Respir Crit Care Med 2021; 205:587-588. [PMID: 34890535 PMCID: PMC8906477 DOI: 10.1164/rccm.202111-2500le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
| | - Tommaso Mauri
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Department of Anesthesia, Critical Care and Emergency, Milano, Italy;
| |
Collapse
|
12
|
Jha AK. Addition of 5% CO 2 to Inspiratory Gas in Preventing Lung Injury Due to Pulmonary Artery Ligation. Am J Respir Crit Care Med 2021; 205:586-587. [PMID: 34890528 PMCID: PMC8906486 DOI: 10.1164/rccm.202110-2425le] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Ajay Kumar Jha
- Jawaharlal Institute of Postgraduate Medical Education and Research, Anesthesiology and Critical Care, Puducherry, India;
| |
Collapse
|
13
|
Masterson CH, O'Toole D, Laffey JG. Inhaled CO2 to Reduce Lung Ischemia and Reperfusion Injuries: Moving Towards Clinical Translation? Am J Respir Crit Care Med 2021; 204:878-879. [PMID: 34375575 PMCID: PMC8534625 DOI: 10.1164/rccm.202107-1665ed] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Claire H Masterson
- National University of Ireland Galway, Regenerative Medicine Institute (REMEDI) at CÚRAM Centre for Research in Medical Devices, Galway, Ireland
| | - Daniel O'Toole
- National University of Ireland Galway, Regenerative Medicine Institute (REMEDI) at CÚRAM Centre for Research in Medical Devices, Galway, Ireland
| | - John G Laffey
- National University of Ireland, Galway, Lung Biology Group, Galway, Ireland;
| |
Collapse
|