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Velamuri SR, Ali Y, Lanfranco J, Gupta P, Hill DM. Inhalation Injury, Respiratory Failure, and Ventilator Support in Acute Burn Care. Clin Plast Surg 2024; 51:221-232. [PMID: 38429045 DOI: 10.1016/j.cps.2023.11.001] [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: 03/03/2024]
Abstract
Sustaining an inhalation injury increases the risk of severe complications and mortality. Current evidential support to guide treatment of the injury or subsequent complications is lacking, as studies either exclude inhalation injury or design limit inferences that can be made. Conventional ventilator modes are most commonly used, but there is no consensus on optimal strategies. Settings should be customized to patient tolerance and response. Data for pharmacotherapy adjunctive treatments are limited.
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Affiliation(s)
- Sai R Velamuri
- Department of Surgery, College of Medicine, University of Tennessee, Health Science Center, Memphis, TN 38103, USA.
| | - Yasmin Ali
- Department of Surgery, College of Medicine, University of Tennessee Health Science Center, 910 Madison Avenue, 2nd floor Suite 217, Memphis, TN 38103, USA
| | - Julio Lanfranco
- Division of Pulmonary and Critical Care, University of Tennessee Health Science Center, 965 Court Avenue Room H316B, Memphis, TN 38103, USA
| | - Pooja Gupta
- Pulmonary and Critical Care, University of Tennessee Health Science Center, 965 court avenue, Room H316B, Memphis, TN 38103, USA
| | - David M Hill
- Department of Pharmacy, Regional One Health, University of Tennessee, 80 madison avenue, Memphis TN 38103, USA
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2
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Sang L, Guo X, Zhao Y, Shi J, Niu Z, Wu Z, Hou S, Fan H, Lv Q. Protective Effect of Nebulized Heparin in the Animal Models of Smoke Inhalation Injury: A Meta-analysis and Systematic Review of Experimental Studies. J Burn Care Res 2023; 44:42-52. [PMID: 36269755 DOI: 10.1093/jbcr/irac156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Indexed: 01/14/2023]
Abstract
The pathophysiological mechanism of abnormal coagulation can result from smoke inhalation injury (SII). Heparin nebulization is a common treatment for lung disorders. This study aimed to use meta-analysis in animal models to examine the effectiveness of atomized heparin on SII. For our online searches, we used the Cochrane Central Register of Controlled Trials, PubMed, Web of Science, Chinese National Knowledge Infrastructure, Chinese BioMedical Literature Database, and Wanfang Database up to January 2022. Data for SII were retrieved and compared to control animals. The studies' findings were determined by combining standardized mean difference (SMD) analysis with 95% confidence intervals (CIs). The findings showed that as compared to the control group, the heparin-treated group had a lower death rate (relative risk 0.42; 95% CI 0.22, 0.80; p < .05). The meta-analysis demonstrated favorable changes in lung physiology, including PaO2/FiO2 (SMD 1.04; 95% CI 0.65, 1.44; p < .001), lung wet-to-dry weight ratio (SMD -1.83; 95% CI -2.47, -1.18; p < .001), and pulmonary shunt Qs/Qt (SMD -0.69; 95% CI -1.29, -0.08; p < .05) after heparin nebulization for lung injury. The present data indicated that pulmonary artery mean pressure in the heparin therapy group was significantly lowered after 24 and 48 hours of therapy, suggesting that the cardiovascular system could recover following heparin treatment. As a result, heparin nebulization appeared to be more effective against SII and improved cardiopulmonary function compared to the control group. Graphical Abstract.
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Affiliation(s)
- Lu Sang
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Xiaoqin Guo
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Yuchen Zhao
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Jie Shi
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Zhifang Niu
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Zhenlong Wu
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Shike Hou
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Haojun Fan
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
| | - Qi Lv
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin, China.,Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin, China
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3
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van Haren FMP, Page C, Laffey JG, Artigas A, Camprubi-Rimblas M, Nunes Q, Smith R, Shute J, Carroll M, Tree J, Carroll M, Singh D, Wilkinson T, Dixon B. Nebulised heparin as a treatment for COVID-19: scientific rationale and a call for randomised evidence. Crit Care 2020; 24:454. [PMID: 32698853 PMCID: PMC7374660 DOI: 10.1186/s13054-020-03148-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 07/03/2020] [Indexed: 12/16/2022] Open
Abstract
Nebulised unfractionated heparin (UFH) has a strong scientific and biological rationale and warrants urgent investigation of its therapeutic potential, for COVID-19-induced acute respiratory distress syndrome (ARDS). COVID-19 ARDS displays the typical features of diffuse alveolar damage with extensive pulmonary coagulation activation resulting in fibrin deposition in the microvasculature and formation of hyaline membranes in the air sacs. Patients infected with SARS-CoV-2 who manifest severe disease have high levels of inflammatory cytokines in plasma and bronchoalveolar lavage fluid and significant coagulopathy. There is a strong association between the extent of the coagulopathy and poor clinical outcomes.The anti-coagulant actions of nebulised UFH limit fibrin deposition and microvascular thrombosis. Trials in patients with acute lung injury and related conditions found inhaled UFH reduced pulmonary dead space, coagulation activation, microvascular thrombosis and clinical deterioration, resulting in increased time free of ventilatory support. In addition, UFH has anti-inflammatory, mucolytic and anti-viral properties and, specifically, has been shown to inactivate the SARS-CoV-2 virus and prevent its entry into mammalian cells, thereby inhibiting pulmonary infection by SARS-CoV-2. Furthermore, clinical studies have shown that inhaled UFH safely improves outcomes in other inflammatory respiratory diseases and also acts as an effective mucolytic in sputum-producing respiratory patients. UFH is widely available and inexpensive, which may make this treatment also accessible for low- and middle-income countries.These potentially important therapeutic properties of nebulised UFH underline the need for expedited large-scale clinical trials to test its potential to reduce mortality in COVID-19 patients.
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Affiliation(s)
- Frank M P van Haren
- Australian National University, Medical School, Canberra, Australia.
- Intensive Care Unit, the Canberra Hospital, Canberra, Australia.
| | - Clive Page
- Sackler Institute of Pulmonary Pharmacology, King's College London, London, UK
| | - John G Laffey
- Anaesthesia and Intensive Care Medicine, School of Medicine, and Regenerative Medicine Institute (REMEDI) at CÚRAM Centre for Research in Medical Devices, Biomedical Sciences Building, National University of Ireland Galway, Galway, Ireland
- Department of Anaesthesia, University Hospital Galway, Saolta Hospital Group, Galway, Ireland
| | - Antonio Artigas
- Critical Center, Corporació Sanitaria Parc Tauli , CIBER Enfermedades Respiratorias, Autonomous University of Barcelona, Sabadell, Spain
| | - Marta Camprubi-Rimblas
- Institut d'Investigació I Innovació Parc Tauli (I3PT), CIBER de Enfermedades Respiratorias, Sabadell, Spain
| | - Quentin Nunes
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Roger Smith
- Department of Critical Care Medicine, St Vincent's Hospital, Melbourne, Australia
| | - Janis Shute
- School of Pharmacy and Biomedical Science, University of Portsmouth, Portsmouth, UK
| | - Mary Carroll
- Department of Respiratory Medicine, University of Southampton, Southampton, UK
| | - Julia Tree
- National Infection Service, Public Health England, Porton Down, UK
| | - Miles Carroll
- National Infection Service, Public Health England, Porton Down, UK
| | - Dave Singh
- Medicines Evaluation Unit, University of Manchester, Manchester, UK
| | - Tom Wilkinson
- Department of Respiratory Medicine, University of Southampton, Southampton, UK
| | - Barry Dixon
- Department of Critical Care Medicine, St Vincent's Hospital, Melbourne, Australia
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4
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Holley AD, Reade MC, Lipman J, Cohen J. There is no fire without smoke! Pathophysiology and treatment of inhalational injury in burns: A narrative review. Anaesth Intensive Care 2020; 48:114-122. [PMID: 32316738 DOI: 10.1177/0310057x20913282] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Smoke inhalation resulting in acute lung injury is a common challenge facing critical care practitioners caring for patients with severe burns, contributing significantly to morbidity and mortality. The intention of this review is to critically evaluate the published literature and trends in the diagnosis, management, implications and novel therapies in caring for patients with inhalation injury.
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Affiliation(s)
- Anthony D Holley
- Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Australia.,Jamieson Trauma Institute, Brisbane, Australia.,Australian Defence Force, Australia
| | - Michael C Reade
- Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Australia.,Jamieson Trauma Institute, Brisbane, Australia.,Australian Defence Force, Australia
| | - Jeffrey Lipman
- Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Australia.,Jamieson Trauma Institute, Brisbane, Australia
| | - Jeremy Cohen
- Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital, Brisbane, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Australia.,Jamieson Trauma Institute, Brisbane, Australia
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5
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Guo B, Bai Y, Ma Y, Liu C, Wang S, Zhao R, Dong J, Ji HL. Preclinical and clinical studies of smoke-inhalation-induced acute lung injury: update on both pathogenesis and innovative therapy. Ther Adv Respir Dis 2019; 13:1753466619847901. [PMID: 31068086 PMCID: PMC6515845 DOI: 10.1177/1753466619847901] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Smoke-inhalation-induced acute lung injury (SI-ALI) is a leading cause of morbidity and mortality in victims of fire tragedies. SI-ALI contributes to an estimated 30% of burn-caused patient deaths, and recently, more attention has been paid to the specific interventions for this devastating respiratory illness. In the last decade, much progress has been made in the understanding of SI-ALI patho-mechanisms and in the development of new therapeutic strategies in both preclinical and clinical studies. This article reviews the recent progress in the treatment of SI-ALI, based on pathophysiology, thermal damage, airway obstruction, the nuclear-factor kappa-B signaling pathway, and oxidative stress. Preclinical therapeutic strategies include use of mesenchymal stem cells, hydrogen sulfide, peroxynitrite decomposition catalysts, and proton-pump inhibitors. Clinical interventions include high-frequency percussive ventilation, perfluorohexane, inhaled anticoagulants, and nebulized epinephrine. The animal model, dose, clinical application, and pharmacology of these medications are summarized. Future directions and further needs for developing innovative therapies are discussed.
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Affiliation(s)
- Bingxin Guo
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan, China
| | - Yichun Bai
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan, China
| | - Yana Ma
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan, China
| | - Cong Liu
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan, China
| | - Song Wang
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan, China
| | - Runzhen Zhao
- Department of Cellular and Molecular Biology, University of Texas Health Science Center at Tyler, Tyler, TX, USA
| | - Jiaxing Dong
- Institute of Lung and Molecular Therapy, Xinxiang Medical University, Xinxiang Henan, China
| | - Hong-Long Ji
- Texas Lung Injury Institute, University of Texas Health Science Center at Tyler, Tyler, TX, USA
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6
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McGinn KA, Weigartz K, Lintner A, Scalese MJ, Kahn SA. Nebulized Heparin With N-Acetylcysteine and Albuterol Reduces Duration of Mechanical Ventilation in Patients With Inhalation Injury. J Pharm Pract 2017; 32:163-166. [PMID: 29233052 DOI: 10.1177/0897190017747143] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Nebulized heparin has been proposed to improve pulmonary function in patients with inhalation injuries. The purpose of this study was to evaluate the impact of nebulized heparin with N-acetylcysteine (NAC) and albuterol on the duration of mechanical ventilation in burn patients. METHODS This is a retrospective study evaluating mechanically ventilated adult patients admitted to a regional burn center with inhalation injury. Outcomes were compared between patients who were prescribed a combination of nebulized heparin with NAC and albuterol versus similar patients who did not. RESULTS A total of 48 patients met inclusion criteria (heparin n = 22; nonheparin n = 26). Patients in the nonheparin group had higher percentage of total body surface area (TBSA) burned (29.00 [5.75-51.88] vs 5.25 [0.50-13.25] %TBSA; P = .009), longer duration of mechanical ventilation (6.50 [2.75-17.00] vs 3.00 [1.00-8.25] days; P = .022), and longer intensive care unit length of stay (LOS) (3.00 [3.00-28.75] vs 5.50 days [2.00-11.25]; P = .033). Upon regression, use of heparin was the only variable associated with reducing the duration of mechanical ventilation ( P = .039). CONCLUSION Nebulized heparin in combination with NAC and albuterol was associated with a significant reduction in the duration of mechanical ventilation.
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Affiliation(s)
- Kaitlin A McGinn
- 1 Department of Pharmacy Practice, Auburn University Harrison School of Pharmacy, Auburn, AL, USA.,2 Department of Surgery, University of South Alabama Medical Center, Mobile, AL, USA
| | - Katie Weigartz
- 1 Department of Pharmacy Practice, Auburn University Harrison School of Pharmacy, Auburn, AL, USA
| | - Alicia Lintner
- 2 Department of Surgery, University of South Alabama Medical Center, Mobile, AL, USA
| | - Michael J Scalese
- 1 Department of Pharmacy Practice, Auburn University Harrison School of Pharmacy, Auburn, AL, USA.,2 Department of Surgery, University of South Alabama Medical Center, Mobile, AL, USA
| | - Steven A Kahn
- 2 Department of Surgery, University of South Alabama Medical Center, Mobile, AL, USA
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7
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Juschten J, Tuinman PR, Juffermans NP, Dixon B, Levi M, Schultz MJ. Nebulized anticoagulants in lung injury in critically ill patients-an updated systematic review of preclinical and clinical studies. ANNALS OF TRANSLATIONAL MEDICINE 2017; 5:444. [PMID: 29264361 DOI: 10.21037/atm.2017.08.23] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pneumonia, inhalation trauma and acute respiratory distress syndrome (ARDS), typical causes of lung injury in critically ill patients, are all three characterized by dysregulated inflammation and coagulation in the lungs. Nebulized anticoagulants are thought to have beneficial effects as they could attenuate pulmonary coagulopathy and maybe even affect pulmonary inflammation. A systematic search of the medical literature was performed using terms referring to aspects of the condition ('pneumonia', 'inhalation trauma' and 'ARDS'), the intervention ('nebulized', 'vaporized', and 'aerosolized') and anticoagulants limited to agents that are commercially available and frequently given or tested in critically ill patients ['heparin', 'danaparoid', 'activated protein C' (APC), 'antithrombin' (AT) and 'tissue factor pathway inhibitor' (TFPI)]. The systematic search identified 16 articles reporting on preclinical studies and 11 articles reporting on human trials. All nebulized anticoagulants attenuate pulmonary coagulopathy in preclinical studies using various models for lung injury, but the effects on inflammation are less consistent. Nebulized heparin, danaparoid and TFPI, but not APC and AT also reduced systemic coagulation. Nebulized heparin in lung injury patients shows contradictory results, and there is concern over systemic side effects of this strategy. Future studies need to focus on the way to nebulize anticoagulants, as well as on efficient but safe dosages, and other side effects.
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Affiliation(s)
- Jenny Juschten
- Laboratory of Experimental Intensive Care and Anesthesiology (L·E·I·C·A), Academic Medical Center, Amsterdam, the Netherlands.,Department of Intensive Care and Research VUmc Intensive Care (REVIVE), VU Medical Center, Amsterdam, the Netherlands.,Department of Intensive Care, Academic Medical Center, Amsterdam, the Netherlands
| | - Pieter R Tuinman
- Department of Intensive Care and Research VUmc Intensive Care (REVIVE), VU Medical Center, Amsterdam, the Netherlands
| | - Nicole P Juffermans
- Laboratory of Experimental Intensive Care and Anesthesiology (L·E·I·C·A), Academic Medical Center, Amsterdam, the Netherlands.,Department of Intensive Care, Academic Medical Center, Amsterdam, the Netherlands
| | - Barry Dixon
- Department of Intensive Care Medicine, St. Vincent's Hospital, Melbourne, Australia
| | - Marcel Levi
- Department of Medicine, University College London Hospitals, London, UK
| | - Marcus J Schultz
- Laboratory of Experimental Intensive Care and Anesthesiology (L·E·I·C·A), Academic Medical Center, Amsterdam, the Netherlands.,Department of Intensive Care, Academic Medical Center, Amsterdam, the Netherlands.,Mahidol-Oxford Research Unit (MORU), Mahidol University, Bangkok, Thailand
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8
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Yildiz-Pekoz A, Ozsoy Y. Inhaled Heparin: Therapeutic Efficacy and Recent Formulations. J Aerosol Med Pulm Drug Deliv 2017; 30:143-156. [PMID: 28418758 DOI: 10.1089/jamp.2015.1273] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Heparin is well known for its anticoagulant and anti-inflammatory properties. Inhaled heparin regimens are increasingly being used to manage lung disease. It has been used to treat cystic fibrosis, thromboembolism, and pulmonary fibrosis, as well as bronchial asthma and asthma-induced airway hypersensitivity. Several preclinical studies attained some useful effects of heparin-administered, parenterally and through inhalation, treatment of lung disease. Besides, recent clinical trials suggest that inhaled heparin for lung diseases is beneficial and safe, but such data remain to be limited. In 2005, the orphan designation was granted by the European Commission for heparin sodium (inhalation use) for the treatment of cystic fibrosis. The positive results of heparin in the pulmonary route necessitate a focus on the preparation and evaluation of heparin in advanced drug delivery systems, namely nano/microparticles and liposomes. Through this pulmonary delivery, heparin is protected from enzymatic degradation within the airway. Heparin is thus passively targeted into the lungs, and long-lasting localized treatment is achieved. On the other hand, these systems have encountered several problems as follows: (1) polymers, such as poly-L-lactide-glycolic acid, poly (lactic acid), and chitosan, used to prepare heparin-loaded microparticle/nanoparticle (MP/NP) systems have not been granted approval for lung application by the FDA and (2) liposomal and NP formulation stability is the main problem of formulation design. We propose that additional in vitro and in vivo research is necessary to assess the clinical applicability of this treatment strategy. The present article discusses heparin treatments for lung diseases and the use of heparin and/or heparin-loaded drugs in advanced delivery systems through the pulmonary route.
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Affiliation(s)
- Ayca Yildiz-Pekoz
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Istanbul University , Istanbul, Turkey
| | - Yildiz Ozsoy
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Istanbul University , Istanbul, Turkey
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9
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Inflammatory Mediators and Oxidative Stress in Animals Subjected to Smoke Inhalation: A Systematic Review. Lung 2016; 194:487-99. [DOI: 10.1007/s00408-016-9879-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 04/11/2016] [Indexed: 01/31/2023]
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10
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Lung [(18)F]fluorodeoxyglucose uptake and ventilation-perfusion mismatch in the early stage of experimental acute smoke inhalation. Anesthesiology 2014; 120:683-93. [PMID: 24051392 DOI: 10.1097/01.anes.0000435742.04859.e8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Acute lung injury occurs in a third of patients with smoke inhalation injury. Its clinical manifestations usually do not appear until 48-72 h after inhalation. Identifying inflammatory changes that occur in pulmonary parenchyma earlier than that could provide insight into the pathogenesis of smoke-induced acute lung injury. Furthermore, noninvasive measurement of such changes might lead to earlier diagnosis and treatment. Because glucose is the main source of energy for pulmonary inflammatory cells, the authors hypothesized that its pulmonary metabolism is increased shortly after smoke inhalation, when classic manifestations of acute lung injury are not yet expected. METHODS In five sheep, the authors induced unilateral injury with 48 breaths of cotton smoke while the contralateral lung served as control. The authors used positron emission tomography with: (1) [F]fluorodeoxyglucose to measure metabolic activity of pulmonary inflammatory cells; and (2) [N]nitrogen in saline to measure shunt and ventilation-perfusion distributions separately in the smoke-exposed and control lungs. RESULTS The pulmonary [F]fluorodeoxyglucose uptake rate was increased at 4 h after smoke inhalation (mean ± SD: 0.0031 ± 0.0013 vs. 0.0026 ± 0.0010 min; P < 0.05) mainly as a result of increased glucose phosphorylation. At this stage, there was no worsening in lung aeration or shunt. However, there was a shift of perfusion toward units with lower ventilation-to-perfusion ratio (mean ratio ± SD: 0.82 ± 0.10 vs. 1.12 ± 0.02; P < 0.05) and increased heterogeneity of the ventilation-perfusion distribution (mean ± SD: 0.21 ± 0.07 vs. 0.13 ± 0.01; P < 0 .05). CONCLUSION Using noninvasive imaging, the authors demonstrated that increased pulmonary [F]fluorodeoxyglucose uptake and ventilation-perfusion mismatch occur early after smoke inhalation.
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11
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Inhaled anticoagulation regimens for the treatment of smoke inhalation-associated acute lung injury: a systematic review. Crit Care Med 2014; 42:413-9. [PMID: 24158173 DOI: 10.1097/ccm.0b013e3182a645e5] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Inhaled anticoagulation regimens are increasingly being used to manage smoke inhalation-associated acute lung injury. We systematically reviewed published and unpublished preclinical and clinical trial data to elucidate the effects of these regimens on lung injury severity, airway obstruction, ventilation, oxygenation, pulmonary infections, bleeding complications, and survival. DATA SOURCES PubMed, Scopus, EMBASE, and Web of Science were searched to identify relevant published studies. Relevant unpublished studies were identified by searching the Australian and New Zealand Clinical Trials Registry, World Health Organization International Clinical Trials Registry Platform, Cochrane Library, ClinicalTrials.gov, MINDCULL.com, Current Controlled Trials, and Google. STUDY SELECTION Inclusion criteria were any preclinical or clinical study in which 1) animals or subjects experienced smoke inhalation exposure, 2) they were treated with nebulized or aerosolized anticoagulation regimens, including heparin, heparinoids, antithrombins, or fibrinolytics (e.g., tissue plasminogen activator), 3) a control and/or sham group was described for preclinical studies, and 4) a concurrent or historical control group described for clinical studies. Exclusion criteria were 1) the absence of a group treated with a nebulized or aerosolized anticoagulation regimen, 2) the absence of a control or sham group, and 3) case reports. DATA EXTRACTION Ninety-nine potentially relevant references were identified. Twenty-seven references met inclusion criteria including 19 preclinical references reporting 18 studies and eight clinical references reporting five clinical studies. DATA SYNTHESIS A systematic review of the literature is provided. Both clinical and methodological diversity precluded combining these studies in a meta-analysis. CONCLUSIONS The high mortality associated with smoke inhalation-associated acute lung injury results from airway damage, mucosal dysfunction, neutrophil infiltration, airway coagulopathy with cast formation, ventilation-perfusion mismatching with shunt, and barotrauma. Inhaled anticoagulation regimens in both preclinical and clinical studies improve survival and decrease morbidity without altering systemic markers of clotting and anticoagulation. In some preclinical and clinical studies, inhaled anticoagulants were associated with a favorable effect on survival. This approach appears sufficiently promising to merit a well-designed prospective study to validate its use in patients with severe smoke inhalation-associated acute lung injury requiring mechanical ventilation.
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12
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Dries DJ, Endorf FW. Inhalation injury: epidemiology, pathology, treatment strategies. Scand J Trauma Resusc Emerg Med 2013; 21:31. [PMID: 23597126 PMCID: PMC3653783 DOI: 10.1186/1757-7241-21-31] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 04/11/2013] [Indexed: 01/19/2023] Open
Abstract
Lung injury resulting from inhalation of smoke or chemical products of combustion continues to be associated with significant morbidity and mortality. Combined with cutaneous burns, inhalation injury increases fluid resuscitation requirements, incidence of pulmonary complications and overall mortality of thermal injury. While many products and techniques have been developed to manage cutaneous thermal trauma, relatively few diagnosis-specific therapeutic options have been identified for patients with inhalation injury. Several factors explain slower progress for improvement in management of patients with inhalation injury. Inhalation injury is a more complex clinical problem. Burned cutaneous tissue may be excised and replaced with skin grafts. Injured pulmonary tissue must be protected from secondary injury due to resuscitation, mechanical ventilation and infection while host repair mechanisms receive appropriate support. Many of the consequences of smoke inhalation result from an inflammatory response involving mediators whose number and role remain incompletely understood despite improved tools for processing of clinical material. Improvements in mortality from inhalation injury are mostly due to widespread improvements in critical care rather than focused interventions for smoke inhalation. Morbidity associated with inhalation injury is produced by heat exposure and inhaled toxins. Management of toxin exposure in smoke inhalation remains controversial, particularly as related to carbon monoxide and cyanide. Hyperbaric oxygen treatment has been evaluated in multiple trials to manage neurologic sequelae of carbon monoxide exposure. Unfortunately, data to date do not support application of hyperbaric oxygen in this population outside the context of clinical trials. Cyanide is another toxin produced by combustion of natural or synthetic materials. A number of antidote strategies have been evaluated to address tissue hypoxia associated with cyanide exposure. Data from European centers supports application of specific antidotes for cyanide toxicity. Consistent international support for this therapy is lacking. Even diagnostic criteria are not consistently applied though bronchoscopy is one diagnostic and therapeutic tool. Medical strategies under investigation for specific treatment of smoke inhalation include beta-agonists, pulmonary blood flow modifiers, anticoagulants and antiinflammatory strategies. Until the value of these and other approaches is confirmed, however, the clinical approach to inhalation injury is supportive.
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Affiliation(s)
- David J Dries
- Department of Surgery, Regions Hospital, St. Paul, MN 55101, USA.
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13
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Tuinman PR, Dixon B, Levi M, Juffermans NP, Schultz MJ. Nebulized anticoagulants for acute lung injury - a systematic review of preclinical and clinical investigations. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2012; 16:R70. [PMID: 22546487 PMCID: PMC3681399 DOI: 10.1186/cc11325] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 04/02/2012] [Accepted: 04/30/2012] [Indexed: 12/16/2022]
Abstract
Background Data from interventional trials of systemic anticoagulation for sepsis inconsistently suggest beneficial effects in case of acute lung injury (ALI). Severe systemic bleeding due to anticoagulation may have offset the possible positive effects. Nebulization of anticoagulants may allow for improved local biological availability and as such may improve efficacy in the lungs and lower the risk of systemic bleeding complications. Method We performed a systematic review of preclinical studies and clinical trials investigating the efficacy and safety of nebulized anticoagulants in the setting of lung injury in animals and ALI in humans. Results The efficacy of nebulized activated protein C, antithrombin, heparin and danaparoid has been tested in diverse animal models of direct (for example, pneumonia-, intra-pulmonary lipopolysaccharide (LPS)-, and smoke inhalation-induced lung injury) and indirect lung injury (for example, intravenous LPS- and trauma-induced lung injury). Nebulized anticoagulants were found to have the potential to attenuate pulmonary coagulopathy and frequently also inflammation. Notably, nebulized danaparoid and heparin but not activated protein C and antithrombin, were found to have an effect on systemic coagulation. Clinical trials of nebulized anticoagulants are very limited. Nebulized heparin was found to improve survival of patients with smoke inhalation-induced ALI. In a trial of critically ill patients who needed mechanical ventilation for longer than two days, nebulized heparin was associated with a higher number of ventilator-free days. In line with results from preclinical studies, nebulization of heparin was found to have an effect on systemic coagulation, but without causing systemic bleedings. Conclusion Local anticoagulant therapy through nebulization of anticoagulants attenuates pulmonary coagulopathy and frequently also inflammation in preclinical studies of lung injury. Recent human trials suggest nebulized heparin for ALI to be beneficial and safe, but data are very limited.
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Affiliation(s)
- Pieter R Tuinman
- Department of Intensive Care Medicine and Laboratory of Experimental Intensive Care and Anesthesiology, Academic Medical Center, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands.
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Thai A, Xiao J, Ammit A, Rohanizadeh R. Development of inhalable formulations of anti-inflammatory drugs to potentially treat smoke inhalation injury in burn victims. Int J Pharm 2010; 389:41-52. [DOI: 10.1016/j.ijpharm.2010.01.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Revised: 01/04/2010] [Accepted: 01/10/2010] [Indexed: 12/01/2022]
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Allen GB, Cloutier ME, Larrabee YC, Tetenev K, Smiley ST, Bates JHT. Neither fibrin nor plasminogen activator inhibitor-1 deficiency protects lung function in a mouse model of acute lung injury. Am J Physiol Lung Cell Mol Physiol 2008; 296:L277-85. [PMID: 19060228 DOI: 10.1152/ajplung.90475.2008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Fibrin impairs surfactant function in vitro, and inhibition of fibrinolysis by plasminogen activator inhibitor (PAI-1) is thought to promote fibrin accumulation in acute lung injury (ALI). This has led to speculation that impaired PAI-1 and fibrin accumulation should protect lung function in ALI. We tested this hypothesis by investigating ALI severity in fibrinogen-deficient (Fgn-/-) and PAI-1-deficient (PAI-1-/-) mice. PAI-1-/-, C57BL/6, Fgn-/-, and Fgn+/- females were anesthetized and allowed to aspirate 4 microl/g of hydrochloric acid (pH 1.0) and then reanesthetized and connected to a ventilator 48 h later. Naive C57BL/6 and Fgn+/- females served as controls. Following deep inflation (DI), forced oscillations were delivered periodically over 8 min to measure changes in elastance (H) as a surrogate of lung derecruitment, at positive end-expiratory pressures (PEEP) of 6, 3, and 1 cmH(2)O. Increases in H following DI in acid-injured mice were greater than naive strain-matched controls. Increases in H were no different between injured PAI-1-/- and C57BL/6, or between injured Fgn-/- and +/- mice, at any PEEP. Pressure-volume curves were no different between injured groups. Total lung fibrin was lower in injured PAI-1-/- and Fgn-/- mice relative to injured C57BL/6 and Fgn+/- mice, respectively, but indices of permeability were no different between strains. Unexpectedly, neither fibrin nor PAI-1 deficiency protects lung mechanical function in mice with acid-induced ALI. We speculate that in vivo lung function may be more closely tied to permeability and alveolar protein in general, rather than being linked specifically to fibrin.
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Affiliation(s)
- Gilman B Allen
- School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan
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In vivo effect of adhesion inhibitor heparin on Legionella pneumophila pathogenesis in a murine pneumonia model. Intensive Care Med 2008; 34:1511-9. [PMID: 18365173 DOI: 10.1007/s00134-008-1063-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Accepted: 12/13/2007] [Indexed: 01/11/2023]
Abstract
OBJECTIVE To examine the effect of intratracheal heparin instillation on Legionella pneumophila-related acute lung injury (ALI) and systemic dissemination. DESIGN Prospective, controlled experimental study. SETTING University research laboratory. INTERVENTIONS A/J mice received 5 microg of sulfated heparin intratracheally co-instilled with 10(6) or 10(8) colony-forming units (CFU) of a virulent isolate of L. pneumophila. MEASUREMENTS AND RESULTS ALI was assessed in control groups (PBS and PBS-heparin) and on days 1, 2 and 3 post-infection, in terms of the lung wet-to-dry (W/D) weight ratios and of lung endothelial permeability to radio-labeled albumin (Perm-I(125)). Lung bacterial loads were measured and systemic spread was assessed by blood and target organ culture. The alveolar inflammatory response was evaluated by measuring the cytokine levels (TNF-alpha, IFN-gamma, IL-6 and IL-12p70) in bronchoalveolar lavage fluids (BALF). Co-instilled heparin improved mouse survival after the 10(8) CFU challenge (p < 0.01). On day 2, heparin co-instillation significantly reduced the W/D ratio and Perm-I(125) (p < 0.01 and p < 0.001 respectively), improved lung bacterial clearance (p < 0.001), prevented systemic dissemination (blood, liver, spleen, kidneys and brain cultures, all p < 0.05) and significantly increased IFN-gamma and IL-12p70 levels in BALF (p < 0.05). CONCLUSIONS Heparin co-instillation during intratracheal L. pneumophila challenge has a protective effect on the alveolar-capillary barrier and prevents bacterial dissemination. These results tend to confirm the competitive inhibition by heparin of L. pneumophila attachment to lung epithelium in vivo, and point to the possible involvement of a heparan-sulfate adhesin in L. pneumophila binding to pneumocytes.
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Affiliation(s)
- Tina L Palmieri
- Shriners Hospitals for Children-Northern California, and Department of Surgery, University of California-Davis, 2425 Stockton Boulevard, Sacramento, CA 95817, USA
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Souza-Fernandes AB, Pelosi P, Rocco PRM. Bench-to-bedside review: the role of glycosaminoglycans in respiratory disease. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2007; 10:237. [PMID: 17118216 PMCID: PMC1794443 DOI: 10.1186/cc5069] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The extracellular matrix (ECM) plays a significant role in the mechanical behaviour of the lung parenchyma. The ECM is composed of a three-dimensional fibre mesh that is filled with various macromolecules, among which are the glycosaminoglycans (GAGs). GAGs are long, linear and highly charged heterogeneous polysaccharides that are composed of a variable number of repeating disaccharide units. There are two main types of GAGs: nonsulphated GAG (hyaluronic acid) and sulphated GAGs (heparan sulphate and heparin, chondroitin sulphate, dermatan sulphate, and keratan sulphate). With the exception of hyaluronic acid, GAGs are usually covalently attached to a protein core, forming an overall structure that is referred to as proteoglycan. In the lungs, GAGs are distributed in the interstitium, in the sub-epithelial tissue and bronchial walls, and in airway secretions. GAGs have important functions in lung ECM: they regulate hydration and water homeostasis; they maintain structure and function; they modulate the inflammatory response; and they influence tissue repair and remodelling. Given the great diversity of GAG structures and the evidence that GAGs may have a protective effect against injury in various respiratory diseases, an understanding of changes in GAG expression that occur in disease may lead to opportunities to develop innovative and selective therapies in the future.
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Affiliation(s)
- Alba B Souza-Fernandes
- Laboratory of Pulmonary Investigation, Carolos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Ilha do Fundão, 21949-900, Rio de Janeiro, Brazil
| | - Paolo Pelosi
- Department of Ambient, Health and Safety, University of Insubria, Viale Borri 57, 21100 Varese, Italy
| | - Patricia RM Rocco
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Ilha do Fundão, 21949-900, Rio de Janeiro, Brazil
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Affiliation(s)
- Daniel L Traber
- Investigational Intensive Care Unit, Department of Anesthesiology, University of Texas Medical Branch and Shriners Burns Hospital for Children, Galveston,TX 77555-0833, USA.
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Cepkova M, Matthay MA. Pharmacotherapy of acute lung injury and the acute respiratory distress syndrome. J Intensive Care Med 2006; 21:119-43. [PMID: 16672636 PMCID: PMC2765330 DOI: 10.1177/0885066606287045] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Acute lung injury and the acute respiratory distress syndrome are common syndromes with a high mortality rate that affect both medical and surgical patients. Better understanding of the pathophysiology of acute lung injury and the acute respiratory distress syndrome and advances in supportive care and mechanical ventilation have led to improved clinical outcomes since the syndrome was first described in 1967. Although several promising pharmacological therapies, including surfactant, nitric oxide, glucocorticoids and lysofylline, have been studied in patients with acute lung injury and the acute respiratory distress syndrome, none of these pharmacological treatments reduced mortality. This article provides an overview of pharmacological therapies of acute lung injury and the acute respiratory distress syndrome tested in clinical trials and current recommendations for their use as well as a discussion of potential future pharmacological therapies including beta(2)-adrenergic agonist therapy, keratinocyte growth factor, and activated protein C.
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Affiliation(s)
- Magda Cepkova
- Cardiovascular Research Institute, University of California San Francisco, CA 94143-0130, USA.
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Inoue Y, Seiyama A, Tanaka H, Ukai I, Akimau P, Nishino M, Shimazu T, Sugimoto H. Protective effects of a selective neutrophil elastase inhibitor (sivelestat) on lipopolysaccharide-induced acute dysfunction of the pulmonary microcirculation. Crit Care Med 2005; 33:1814-22. [PMID: 16096460 DOI: 10.1097/01.ccm.0000172547.54086.ad] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate the effect of a neutrophil elastase inhibitor, sivelestat, on lipopolysaccharide-induced acute lung injury through analysis of hemodynamic changes in the pulmonary microcirculation. DESIGN Randomized animal study. SETTING Medical school laboratory. SUBJECTS Twenty-seven Wistar rats (15 rats for microspectroscopic observations, 12 rats for measurements of neutrophil elastase activity and wet-to-dry ratio). INTERVENTIONS Thoracosternotomy was performed on male Wistar rats under continuous anesthesia and mechanical ventilation. Rats were divided into three groups (n = 5 each groups) on the basis of the reagent used: lipopolysaccharide group (100 microg/kg lipopolysaccharide intravenously), sivelestat group (10 mg/kg sivelestat; 100 microg/kg lipopolysaccharide intravenously), and control group (saline only, intravenously). MEASUREMENTS AND MAIN RESULTS We measured morphologic changes and hemodynamic variables, including tissue blood flow, erythrocyte velocity, erythrocyte count, thickness of interalveolar septa, and leukocyte adhesion in the pulmonary microcirculation, with a video-rate (33 msec/frame) dual-spot microspectroscopy system (DSMSS) and a laser-Doppler flowmeter. Blood-free wet-to-dry ratio and neutrophil elastase activity in bronchoalveolar lavage fluid, serum, and supernatant of lung homogenate were measured in another set of experiments (n = 4 for each group). Sixty minutes after lipopolysaccharide administration, severe thickening of the interalveolar septa was observed in the lipopolysaccharide but not the sivelestat group. In the lipopolysaccharide group, DSMSS measurements of erythrocyte velocity and hemoglobin oxygenation in single capillaries were decreased significantly (vs. control p < .05, vs. sivelestat p < .01), whereas tissue blood flow and erythrocyte velocity measurements from laser-Doppler flowmeter were increased significantly (vs. control p < .05, vs. sivelestat p < .01). The number of adherent leukocytes was increased significantly in the lipopolysaccharide group at 30, 45, and 60 mins after lipopolysaccharide administration (vs. control p < .01, vs. sivelestat p < .05). The number of adherent leukocytes did not increase in the sivelestat group. The wet-to-dry ratio was significantly higher in the lipopolysaccharide group than in control (p < .05) and sivelestat (p < .05) groups. Neutrophil elastase activities in the bronchoalveolar lavage fluid, serum, and lung tissue were all significantly lower in the sivelestat group than in the lipopolysaccharide group (p < .05). CONCLUSIONS Lipopolysaccharide induces leukocyte adhesion in the pulmonary microcirculation, resulting in decreased tissue hemoglobin oxygen and alveolar and interstitial edema. The selective neutrophil elastase inhibitor sivelestat reduces neutrophil elastase activity and attenuates acute changes in the pulmonary microcirculation.
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Affiliation(s)
- Yoshiaki Inoue
- Department of Traumatology and Acute Critical Medicine, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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Abstract
INTRODUCTION Smoke inhalation and respiratory complications are still the major causes of mortality in severely burned patients. STATE OF THE ART The diagnosis is suspected clinically on the basis of history and physical examination and can be confirmed bronchoscopically. Respiratory failure in burned patients occurs through a number of associated mechanisms. Pneumonitis and adult respiratory distress syndrome (ARDS) are common early complications. New pulmonary treatments and advances in ventilation have reduced the incidence of both barotrauma and infectious complications. Tracheal stenosis can occur as a late complication of prolonged mechanical ventilation. PERSPECTIVES Clinical and experimental studies have shown that damage to the mucosal barrier and the release of inflammatory mediators are the most important pathophysiological events following smoke inhalation. Manipulation of the inflammatory response following inhalation may be a treatment option in the distant future. CONCLUSION Inhalation injury occurring in burned patients can produce severe respiratory and systemic complications.
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Affiliation(s)
- L Bargues
- Centre de Traitement des Brûlés, Hôpital d'Instruction des Armées Percy, Clamart, France.
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Abstract
A lesão inalatória é hoje a principal causa de morte nos pacientes queimados, motivo pelo qual se justifica o grande número de estudos publicados sobre o assunto. Os mecanismos envolvidos na gênese da lesão inalatória envolvem tanto os fatores de ação local quanto os de ação sistêmica, o que acaba por aumentar muito as repercussões da lesão. Atualmente, buscam-se ferramentas que permitam o diagnóstico cada vez mais precoce da lesão inalatória e ainda estratégias de tratamento que minimizem as conseqüências da lesão já instalada. Esta revisão aborda os mecanismos fisiopatológicos, os métodos diagnósticos e as estratégias de tratamento dos pacientes vítimas de lesão inalatória. Ressalta ainda as perspectivas terapêuticas em desenvolvimento.
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Park MS, Cancio LC, Jordan BS, Brinkley WW, Rivera VR, Dubick MA. Assessment of oxidative stress in lungs from sheep after inhalation of wood smoke. Toxicology 2004; 195:97-112. [PMID: 14751667 DOI: 10.1016/j.tox.2003.09.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
To elucidate potential dose-dependent mechanisms associated with wood smoke inhalation injury, the present study evaluated antioxidant status and the extent of pulmonary injury in sheep after graded exposure to smoke. Adult, male sheep (n=4-5 per group) were anesthetized and received 0, 5, 10 or 16 units of cooled western pine bark smoke, corresponding to 0, 175, 350 and 560 s, respectively, of smoke dwell time in the airways and lung. Smoke was mixed at a 1:1 ratio with 100% O2 to minimize hypoxia. Plasma and expired breath samples were collected pre-smoke, and 6, 12, 18, 24, 36 and 48 h after smoke exposure. Sheep were euthanatized 48 h after smoke exposure and lung and airway sections were evaluated histologically for injury and biochemically for indices of oxidative stress. Plasma thiobarbituric acid reactive substances (TBARS) were 66 and 69% higher than controls after moderate and severe smoke exposure at 48 h, whereas total antioxidant potential was not statistically different among groups at any time after exposure. Lung TBARS showed a dose-dependent response to smoke inhalation and were approximately 2-, 3- and 4-fold higher, respectively, than controls after exposure to 5, 10 and 16 units of smoke. Lung myeloperoxidase (MPO) activity was also higher in smoke-exposed animals than controls, and MPO activity was markedly elevated (19- and 22-fold higher than controls in right apical and medial lobes) in response to severe smoke exposure. Smoke exposure also induced a dose-dependent injury to tracheobronchial epithelium and lung parenchyma. Taken together these data show that few indices of oxidative stress responded in a dose-dependent manner to graded doses of smoke inhalation, although most of the indices measured in lung were affected by the highest dose of smoke. Additional time course studies are necessary to determine whether these oxidants are a cause or a consequence of the airway and lung injury associated with exposure to wood smoke.
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Affiliation(s)
- Myung S Park
- US Army Institute of Surgical Research, Fort Sam Houston, TX 78234-6315, USA
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Sheridan RL, Tompkins RG. What's new in burns and metabolism. J Am Coll Surg 2004; 198:243-63. [PMID: 14759783 DOI: 10.1016/j.jamcollsurg.2003.11.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Accepted: 11/10/2003] [Indexed: 12/31/2022]
Affiliation(s)
- Robert L Sheridan
- Burn Surgery Service, Shriners Hospital for Children, 51 Blossom Street, Boston, MA 02114, USA
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Abstract
OBJECTIVE To review the rationale for evaluating anticoagulant therapies in acute lung injury (ALI) and to review selected data regarding the effectiveness of anticoagulants in animals and human patients with ALI and acute respiratory distress syndrome. DATA SOURCES Published literature on coagulation alterations and anticoagulant strategies in ALI during the past 25 yrs. DATA EXTRACTION AND SYNTHESIS In the lung, alveolar and interstitial fibrin deposition are the hallmarks of early phase ALI. Local procoagulant activity and reduced fibrinolysis constitute the rationale for anticoagulant use in the treatment of ALI. An activated complex of tissue factor and factor VIIa triggers procoagulant activity in the lung, with subsequent thrombin formation and fibrin deposition. Increased pulmonary vascular permeability and leukocyte accumulation have been successfully prevented in animals treated with tissue factor/activated factor VII pathway inhibitor. In humans, a phase II study evaluating tissue factor pathway inhibitor in the treatment of severe sepsis suggested that lung function in acute respiratory distress syndrome patients was improved. However, the phase III trial failed to demonstrate a survival benefit; data regarding respiratory dysfunction have not yet been published. Heparin, despite effectively inhibiting thrombin formation, has not shown consistent benefits in reducing lung injury, and its efficacy has not yet been evaluated in a controlled study. Antithrombin administration in animals has shown consistent benefits with ALI, but clinical studies have failed to demonstrate reductions in mortality and lung injury. Activated protein C administration has been shown to improve survival and lung function in both animal and clinical studies. Soluble thrombomodulin has been shown to improve ALI in animals, and it is currently being evaluated in humans with sepsis. Finally, plasminogen activators may improve gas exchange in ALI, but studies in humans are limited.
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Cox CS. Heparin for smoke inhalation injury. Crit Care Med 2003; 31:1291. [PMID: 12682515 DOI: 10.1097/01.ccm.0000060012.24387.eb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Affiliation(s)
- Jeffrey R Saffle
- Department of Surgery, Intermountain Burn Center, University of Utah Health Center, Salt Lake City, UT 84132, USA
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