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Azamfirei R. Artificial Intelligence: The Next Blockbuster Drug in Critical Care? J Crit Care Med (Targu Mures) 2023; 9:61-63. [PMID: 37593251 PMCID: PMC10429614 DOI: 10.2478/jccm-2023-0017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 04/30/2023] [Indexed: 08/19/2023] Open
Affiliation(s)
- Razvan Azamfirei
- Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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2
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Bollag WB, Gonzales JN. Phosphatidylglycerol and surfactant: A potential treatment for COVID-19? Med Hypotheses 2020; 144:110277. [PMID: 33254581 PMCID: PMC7493731 DOI: 10.1016/j.mehy.2020.110277] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/11/2020] [Accepted: 09/12/2020] [Indexed: 01/08/2023]
Abstract
A hypothesis concerning the potential utility of surfactant supplementation for the treatment of critically ill patients with COVID-19 is proposed, along with a brief summary of the data in the literature supporting this idea. It is thought that surfactant, which is already approved by the Food and Drug Administration for intratracheal administration to treat neonatal respiratory distress syndrome in pre-term infants, could benefit COVID-19-infected individuals by: (1) restoring surfactant damaged by lung infection and/or decreased due to the virus-induced death of the type II pneumocytes that produce it and (2) reducing surface tension to decrease the work of breathing and limit pulmonary edema. In addition, a constituent of surfactant, phosphatidylglycerol, could mitigate COVID-19-induced lung pathology by: (3) decreasing excessive innate immune system stimulation via its inhibition of toll-like receptor-2 and -4 activation by microbial components and cellular proteins released by damaged cells, thereby limiting inflammation and the resultant pulmonary edema, and (4) possibly blocking spread of the viral infection to non-infected cells in the lung. Therefore, it is suggested that surfactant preparations containing phosphatidylglycerol be tested for their ability to improve lung function in critically ill patients with COVID-19.
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Affiliation(s)
- Wendy B Bollag
- Charlie Norwood VA Medical Center, Augusta, GA 30904, United States; Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA 30912, United States; Department of Dermatology, Medical College of Georgia at Augusta University, Augusta, GA 30912, United States; Department of Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, United States.
| | - Joyce N Gonzales
- Department of Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, United States
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Viola H, Chang J, Grunwell JR, Hecker L, Tirouvanziam R, Grotberg JB, Takayama S. Microphysiological systems modeling acute respiratory distress syndrome that capture mechanical force-induced injury-inflammation-repair. APL Bioeng 2019; 3:041503. [PMID: 31768486 PMCID: PMC6874511 DOI: 10.1063/1.5111549] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 11/08/2019] [Indexed: 12/14/2022] Open
Abstract
Complex in vitro models of the tissue microenvironment, termed microphysiological systems, have enormous potential to transform the process of discovering drugs and disease mechanisms. Such a paradigm shift is urgently needed in acute respiratory distress syndrome (ARDS), an acute lung condition with no successful therapies and a 40% mortality rate. Here, we consider how microphysiological systems could improve understanding of biological mechanisms driving ARDS and ultimately improve the success of therapies in clinical trials. We first discuss how microphysiological systems could explain the biological mechanisms underlying the segregation of ARDS patients into two clinically distinct phenotypes. Then, we contend that ARDS-mimetic microphysiological systems should recapitulate three critical aspects of the distal airway microenvironment, namely, mechanical force, inflammation, and fibrosis, and we review models that incorporate each of these aspects. Finally, we recognize the substantial challenges associated with combining inflammation, fibrosis, and/or mechanical force in microphysiological systems. Nevertheless, complex in vitro models are a novel paradigm for studying ARDS, and they could ultimately improve patient care.
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Affiliation(s)
| | - Jonathan Chang
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA
| | - Jocelyn R. Grunwell
- Department of Pediatrics, Division of Critical Care Medicine, Children's Healthcare of Atlanta at Egleston, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Louise Hecker
- Division of Pulmonary, Allergy and Critical Care and Sleep Medicine, University of Arizona, Tucson, Arizona 85724, USA and Southern Arizona Veterans Affairs Health Care System, Tucson, Arizona 85723, USA
| | - Rabindra Tirouvanziam
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia 30322, USA and Center for CF and Airways Disease Research, Children's Healthcare of Atlanta, Atlanta, Georgia 30322, USA
| | - James B. Grotberg
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
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Mok YH, Lee JH, Rehder KJ, Turner DA. Adjunctive treatments in pediatric acute respiratory distress syndrome. Expert Rev Respir Med 2014; 8:703-16. [PMID: 25119574 DOI: 10.1586/17476348.2014.948854] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Acute respiratory distress syndrome (ARDS) is a devastating process that involves pulmonary inflammation, alveolar damage and hypoxemic respiratory failure. Although advances in management approaches over the past two decades have resulted in significantly improved outcomes, death from pediatric ARDS may still occur in up to 35% of patients. While invasive mechanical ventilation is an essential component of ARDS management, various adjuncts have been utilized as treatment for these patients. However, evidence-based data in infants and children in this area are lacking. In this article, the authors review the available evidence supporting (or not supporting) the use of non-ventilatory adjunctive strategies in the management of pediatric ARDS, including prone positioning, pulmonary vasodilators, β-agonists, steroids and surfactant.
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Affiliation(s)
- Yee Hui Mok
- Children's Intensive Care Unit, KK Women's and Children's Hospital, 100 Bukit Timah Road, Singapore
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5
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Zuo YY, Neumann AW. Pulmonary Surfactant and its in vitro Assessment Using Axisymmetric Drop Shape Analysis (ADSA): A Review. TENSIDE SURFACT DET 2013. [DOI: 10.3139/113.100255] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Recent progress in the study of pulmonary surfactant is reviewed. The first half of this paper provides general background in both physiological and clinical perspectives. The second half focuses on the in vitro assessment of pulmonary surfactant using methods based on a drop shape technique, Axisymmetric Drop Shape Analysis (ADSA). Theories, experiments, and techniques of image analysis used in these ADSA methods are briefly described. Typical applications of these methods are discussed in detail. It is concluded that the accuracy, versatility, and simplicity of these ADSA methods render them suitable to the study of pulmonary surfactant.
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Meng H, Sun Y, Lu J, Fu S, Meng Z, Scott M, Li Q. Exogenous surfactant may improve oxygenation but not mortality in adult patients with acute lung injury/acute respiratory distress syndrome: a meta-analysis of 9 clinical trials. J Cardiothorac Vasc Anesth 2012; 26:849-56. [PMID: 22265270 PMCID: PMC9942513 DOI: 10.1053/j.jvca.2011.11.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To evaluate whether exogenous surfactant therapy may be useful in adult patients with acute lung injury or acute respiratory distress syndrome, using a meta-analysis of published clinical trials. DESIGN A comprehensive literature search was performed to identify all randomized clinical trials examining the effects of the treatment of acute lung injury/acute respiratory distress syndrome with exogenous surfactant in adults. The primary outcome measurement was mortality 28 or 30 days after randomization. Secondary outcome measurements included a change in the ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen in the first 24 hours or after 120 hours, the number of ventilation-free days, and any adverse effects. The meta-analysis was performed using the Review Manager 5.0.0 system. PARTICIPANTS Randomized clinical trials. INTERVENTION Meta-analysis of 9 trials. MEASUREMENTS AND MAIN RESULTS Nine trials involving 2,575 patients were included in the meta-analysis. The analysis showed that treatment with exogenous pulmonary surfactant does not decrease mortality significantly. There was a significant effect of exogenous surfactant treatment on the change in the partial pressure of arterial oxygen/fraction of inspired oxygen ratio in the first 24 hours but this was lost by 120 hours. The duration of ventilation trended lower in surfactant-treated patients but this was not significant. In addition, surfactant-treated patients had a significantly higher risk of adverse effects. CONCLUSIONS An exogenous surfactant may improve oxygenation over the first 24 hours after administration. However, treatment does not improve mortality and oxygenation over ≥120 hours after administration and results in a high rate of adverse effects. Therefore, the present data suggest that an exogenous surfactant cannot be considered an effective adjunctive therapy in patients with acute lung injury/acute respiratory distress syndrome.
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Affiliation(s)
- Haoyu Meng
- Department of Anesthesiology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China,First Clinical Medical College of Nanjing Medical University, Nanjing, China
| | - Ying Sun
- First Clinical Medical College of Nanjing Medical University, Nanjing, China
| | - Jun Lu
- Department of Anesthesiology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China
| | - Shukun Fu
- Department of Anesthesiology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China
| | - Zhaoyi Meng
- Department of Surgery, Xinyi People's Hospital, Xinyi, Jiangsu Province, China
| | - Melanie Scott
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA
| | - Quan Li
- Department of Anesthesiology, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China,Address reprint requests to Quan Li, MD, PhD, Department of Anesthesiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, 301 Yanchang-zhong Road, Shanghai 200072, China
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7
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Derecruitment Test and Surfactant Therapy in Patients with Acute Lung Injury. Crit Care Res Pract 2012; 2012:428798. [PMID: 22928094 PMCID: PMC3426173 DOI: 10.1155/2012/428798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 07/05/2012] [Indexed: 11/17/2022] Open
Abstract
Introduction. A recruitment maneuver (RM) may improve gas exchange in acute lung injury (ALI). The aim of our study was to assess the predictive value of a derecruitment test in relation to RM and to evaluate the efficacy of RM combined with surfactant instillation in patients with ALI.Materials and Methods. Thirteen adult mechanically ventilated patients with ALI were enrolled into a prospective pilot study. The patients received protective ventilation and underwent RM followed by a derecruitment test. After a repeat RM, bovine surfactant (surfactant group,n=6) or vehicle only (conventional therapy group,n=7) was instilled endobronchially. We registered respiratory and hemodynamic parameters, including extravascular lung water index (EVLWI).Results. The derecruitment test decreased the oxygenation in 62% of the patients. We found no significant correlation between the responses to the RM and to the derecruitment tests. The baseline EVLWI correlated with changes in SpO2following the derecruitment test. The surfactant did not affect gas exchange and lung mechanics but increased EVLWI at 24 and 32 hrs.Conclusions. Our study demonstrated no predictive value of the derecruitment test regarding the effects of RM. Surfactant instillation was not superior to conventional therapy and might even promote pulmonary edema in ALI.
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Baron RM, Lopez-Guzman S, Riascos DF, Macias AA, Layne MD, Cheng G, Harris C, Chung SW, Reeves R, von Andrian UH, Perrella MA. Distamycin A inhibits HMGA1-binding to the P-selectin promoter and attenuates lung and liver inflammation during murine endotoxemia. PLoS One 2010; 5:e10656. [PMID: 20498830 PMCID: PMC2871042 DOI: 10.1371/journal.pone.0010656] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Accepted: 04/17/2010] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND The architectural transcription factor High Mobility Group-A1 (HMGA1) binds to the minor groove of AT-rich DNA and forms transcription factor complexes ("enhanceosomes") that upregulate expression of select genes within the inflammatory cascade during critical illness syndromes such as acute lung injury (ALI). AT-rich regions of DNA surround transcription factor binding sites in genes critical for the inflammatory response. Minor groove binding drugs (MGBs), such as Distamycin A (Dist A), interfere with AT-rich region DNA binding in a sequence and conformation-specific manner, and HMGA1 is one of the few transcription factors whose binding is inhibited by MGBs. OBJECTIVES To determine whether MGBs exert beneficial effects during endotoxemia through attenuating tissue inflammation via interfering with HMGA1-DNA binding and modulating expression of adhesion molecules. METHODOLOGY/PRINCIPAL FINDINGS Administration of Dist A significantly decreased lung and liver inflammation during murine endotoxemia. In intravital microscopy studies, Dist A attenuated neutrophil-endothelial interactions in vivo following an inflammatory stimulus. Endotoxin induction of P-selectin expression in lung and liver tissue and promoter activity in endothelial cells was significantly reduced by Dist A, while E-selectin induction was not significantly affected. Moreover, Dist A disrupted formation of an inducible complex containing NF-kappaB that binds an AT-rich region of the P-selectin promoter. Transfection studies demonstrated a critical role for HMGA1 in facilitating cytokine and NF-kappaB induction of P-selectin promoter activity, and Dist A inhibited binding of HMGA1 to this AT-rich region of the P-selectin promoter in vivo. CONCLUSIONS/SIGNIFICANCE We describe a novel targeted approach in modulating lung and liver inflammation in vivo during murine endotoxemia through decreasing binding of HMGA1 to a distinct AT-rich region of the P-selectin promoter. These studies highlight the ability of MGBs to function as molecular tools for dissecting transcriptional mechanisms in vivo and suggest alternative treatment approaches for critical illness.
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Affiliation(s)
- Rebecca M Baron
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America.
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9
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Acosta EJ, Policova Z, Lee S, Dang A, Hair ML, Neumann AW. Restoring the activity of serum-inhibited bovine lung extract surfactant (BLES) using cationic additives. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:489-97. [DOI: 10.1016/j.bbamem.2010.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 01/07/2010] [Accepted: 01/12/2010] [Indexed: 10/19/2022]
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Acosta EJ, Policova Z, Lee S, Dang A, Hair ML, Neumann AW. Restoring the charge and surface activity of bovine lung extract surfactants with cationic and anionic polysaccharides. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:882-90. [PMID: 20144883 DOI: 10.1016/j.bbamem.2010.01.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Revised: 12/25/2009] [Accepted: 01/25/2010] [Indexed: 11/24/2022]
Abstract
Chitosan, a cationic polysaccharide, has been found to improve the surface activity of lung surfactant extracts in the presence of various inhibitors. It has been proposed that chitosan binds to anionic lipids (e.g. phosphatidyl glycerols) in lung surfactants, producing stable lipid films at the air-water interface. This binding also reverses the net charge of the surfactant aggregates, from negative to positive. Unfortunately, positively charged aggregates may adsorb or interact with the negatively charged epithelial tissue, leading to poor surfactant performance. To address this issue an anionic polysaccharide, dextran sulfate (dexS), was used as a secondary coating to reverse the charge of chitosan-lung surfactant extracts without affecting the surface activity of the preparation. The dynamic surface tension and zeta potential of bovine lipid extract surfactant (BLES) containing chitosan chloride (chiCl) and dexS were evaluated as a function of dexS concentration. These studies were conducted in the absence and presence of sodium bicarbonate buffer, and in the absence and presence of bovine serum used as model inhibitor. It was determined that using an appropriate concentration of dexS, especially at physiological pH, it is possible to restore the negative charge of the surfactant aggregates, and retain their surface activity, even in the presence of bovine serum. High concentrations of dexS affect the binding of chiCl to BLES, and the surface activity of the preparation.
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Affiliation(s)
- Edgar J Acosta
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S3E5, Canada.
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Marraro GA, Denaro C, Spada C, Luchetti M, Giansiracusa C. Selective medicated (saline + natural surfactant) bronchoalveolar lavage in unilateral lung contusion. A clinical randomized controlled trial. J Clin Monit Comput 2009; 24:73-81. [PMID: 20012912 DOI: 10.1007/s10877-009-9213-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Accepted: 11/25/2009] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Open lung and low tidal volume ventilation appear to be a promising ventilation for chest trauma as it can reduce ARDS and improve outcome. Local therapy (e.g. BAL) can be synergic to remove from the lung the debris, mitigate inflammatory cascade and avoid damage spreading to not compromised lung areas. MATERIALS AND METHODS 44 pulmonary contused patients were randomized to receive broncho-suction and volume controlled low tidal volume ventilation-VCLTVV (Control Group) or the same ventilation plus medicated (saline + surfactant) BAL (Treatment Group). Tidal volume <10 ml/kg, PEEP of 10-12 cm H(2)O and PaO(2) 60-100 mm Hg and PaCO(2) 35-45 mm Hg were used in both groups. BAL was performed using a fiberscope. 4 boluses of 25 ml saline with 2.4 mg/ml of surfactant were introduced into each contused lobe in which, subsequently, 240 mg of surfactant was instilled. RESULTS All patients survived. In the Control Group 18 patients developed pneumonia, 5 ARDS and days of intubation were 11.50 (3.83) compared to 5.05 (1.21) of Treatment Group in which OI and PaO(2)/FiO(2) significantly improved from 36 h. CONCLUSIONS VCLTVV alone was not able to prevent ARDS and infection in the Control Group as the reduction of intubation. In the Treatment Group, VCLTVV and medicated BAL facilitated the removal of degradated lung material and recruited the contused lung regions, enabling the healing of the lung pathology.
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Affiliation(s)
- Giuseppe A Marraro
- Anesthesia and Intensive Care Department, A.O. Fatebenefratelli and Ophthalmiatric Hospital, Milan, Italy.
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Riva D, Contador R, Baez-Garcia C, Xisto D, Cagido V, Martini S, Morales M, Rocco P, Faffe D, Zin W. Recruitment maneuver: RAMP versus CPAP pressure profile in a model of acute lung injury. Respir Physiol Neurobiol 2009; 169:62-8. [DOI: 10.1016/j.resp.2009.08.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Revised: 08/18/2009] [Accepted: 08/19/2009] [Indexed: 12/21/2022]
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Lauer S, Fischer LG, Stubbe HD, Van Aken H, Westphal M. [Value of surfactant replacement therapy in the treatment of acute respiratory distress syndrome]. Anaesthesist 2009; 55:433-42. [PMID: 16440205 DOI: 10.1007/s00101-006-0978-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Acute respiratory distress syndrome (ARDS) is a common, devastating clinical problem arising from a number of conditions, such as pneumonia, trauma or sepsis. Because of its significant mortality and morbidity, ARDS has been in the focus of extensive experimental and clinical research. Since there is little doubt that alterations of the surfactant system contribute to lung dysfunction and the onset of ARDS, several clinical studies examined the therapeutic safety and efficacy of a surfactant replacement therapy. Clinical experience with exogenous surfactant has proven inconsistent as a therapeutic modality for adult patients with ARDS. This is mainly due to a number of confounding factors, e.g. severity of injury at the time of treatment, dosing regimes and delivery methods used in different trials. However, current data suggest that patients with direct ARDS (e.g. pneumonia, aspiration) could benefit from surfactant replacement therapy rather than patients with indirect ARDS (e.g. sepsis, trauma). Although surfactant replacement therapy has been shown to significantly reduce mortality in neonates with ARDS, there has been no large randomised clinical trial showing that exogenous surfactant improves outcome in adults with respiratory failure. Therefore, surfactant therapy cannot be recommended for routine clinical use in adult patients and has to be considered as a last resort treatment.
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Affiliation(s)
- S Lauer
- Klinik und Poliklinik für Anästhesiologie und Operative Intensivmedizin, Universitätsklinikum Münster, Germany.
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Christmann U, Buechner-Maxwell VA, Witonsky SG, Hite RD. Role of lung surfactant in respiratory disease: current knowledge in large animal medicine. J Vet Intern Med 2009; 23:227-42. [PMID: 19192153 DOI: 10.1111/j.1939-1676.2008.0269.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Lung surfactant is produced by type II alveolar cells as a mixture of phospholipids, surfactant proteins, and neutral lipids. Surfactant lowers alveolar surface tension and is crucial for the prevention of alveolar collapse. In addition, surfactant contributes to smaller airway patency and improves mucociliary clearance. Surfactant-specific proteins are part of the innate immune defense mechanisms of the lung. Lung surfactant alterations have been described in a number of respiratory diseases. Surfactant deficiency (quantitative deficit of surfactant) in premature animals causes neonatal respiratory distress syndrome. Surfactant dysfunction (qualitative changes in surfactant) has been implicated in the pathophysiology of acute respiratory distress syndrome and asthma. Analysis of surfactant from amniotic fluid allows assessment of fetal lung maturity (FLM) in the human fetus and exogenous surfactant replacement therapy is part of the standard care in premature human infants. In contrast to human medicine, use and success of FLM testing or surfactant replacement therapy remain limited in veterinary medicine. Lung surfactant has been studied in large animal models of human disease. However, only a few reports exist on lung surfactant alterations in naturally occurring respiratory disease in large animals. This article gives a general review on the role of lung surfactant in respiratory disease followed by an overview of our current knowledge on surfactant in large animal veterinary medicine.
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Affiliation(s)
- U Christmann
- Department of Large Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Duck Pond Drive, Phase II, Blacksburg, VA 24061, USA.
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Zuo YY, Veldhuizen RAW, Neumann AW, Petersen NO, Possmayer F. Current perspectives in pulmonary surfactant--inhibition, enhancement and evaluation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:1947-77. [PMID: 18433715 DOI: 10.1016/j.bbamem.2008.03.021] [Citation(s) in RCA: 361] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 03/26/2008] [Accepted: 03/26/2008] [Indexed: 02/06/2023]
Abstract
Pulmonary surfactant (PS) is a complicated mixture of approximately 90% lipids and 10% proteins. It plays an important role in maintaining normal respiratory mechanics by reducing alveolar surface tension to near-zero values. Supplementing exogenous surfactant to newborns suffering from respiratory distress syndrome (RDS), a leading cause of perinatal mortality, has completely altered neonatal care in industrialized countries. Surfactant therapy has also been applied to the acute respiratory distress syndrome (ARDS) but with only limited success. Biophysical studies suggest that surfactant inhibition is partially responsible for this unsatisfactory performance. This paper reviews the biophysical properties of functional and dysfunctional PS. The biophysical properties of PS are further limited to surface activity, i.e., properties related to highly dynamic and very low surface tensions. Three main perspectives are reviewed. (1) How does PS permit both rapid adsorption and the ability to reach very low surface tensions? (2) How is PS inactivated by different inhibitory substances and how can this inhibition be counteracted? A recent research focus of using water-soluble polymers as additives to enhance the surface activity of clinical PS and to overcome inhibition is extensively discussed. (3) Which in vivo, in situ, and in vitro methods are available for evaluating the surface activity of PS and what are their relative merits? A better understanding of the biophysical properties of functional and dysfunctional PS is important for the further development of surfactant therapy, especially for its potential application in ARDS.
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Affiliation(s)
- Yi Y Zuo
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada
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Kang N, Policova Z, Bankian G, Hair ML, Zuo YY, Neumann AW, Acosta EJ. Interaction between chitosan and bovine lung extract surfactants. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:291-302. [DOI: 10.1016/j.bbamem.2007.10.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2007] [Revised: 09/27/2007] [Accepted: 10/02/2007] [Indexed: 11/28/2022]
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17
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Walther FJ, Waring AJ, Hernandez-Juviel JM, Gordon LM, Schwan AL, Jung CL, Chang Y, Wang Z, Notter RH. Dynamic surface activity of a fully synthetic phospholipase-resistant lipid/peptide lung surfactant. PLoS One 2007; 2:e1039. [PMID: 17940603 PMCID: PMC2013942 DOI: 10.1371/journal.pone.0001039] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Accepted: 09/20/2007] [Indexed: 11/18/2022] Open
Abstract
Background This study examines the surface activity and resistance to phospholipase degradation of a fully-synthetic lung surfactant containing a novel diether phosphonolipid (DEPN-8) plus a 34 amino acid peptide (Mini-B) related to native surfactant protein (SP)-B. Activity studies used adsorption, pulsating bubble, and captive bubble methods to assess a range of surface behaviors, supplemented by molecular studies using Fourier transform infrared (FTIR) spectroscopy, circular dichroism (CD), and plasmon resonance. Calf lung surfactant extract (CLSE) was used as a positive control. Results DEPN-8+1.5% (by wt.) Mini-B was fully resistant to degradation by phospholipase A2 (PLA2) in vitro, while CLSE was severely degraded by this enzyme. Mini-B interacted with DEPN-8 at the molecular level based on FTIR spectroscopy, and had significant plasmon resonance binding affinity for DEPN-8. DEPN-8+1.5% Mini-B had greatly increased adsorption compared to DEPN-8 alone, but did not fully equal the very high adsorption of CLSE. In pulsating bubble studies at a low phospholipid concentration of 0.5 mg/ml, DEPN-8+1.5% Mini-B and CLSE both reached minimum surface tensions <1 mN/m after 10 min of cycling. DEPN-8 (2.5 mg/ml)+1.5% Mini-B and CLSE (2.5 mg/ml) also reached minimum surface tensions <1 mN/m at 10 min of pulsation in the presence of serum albumin (3 mg/ml) on the pulsating bubble. In captive bubble studies, DEPN-8+1.5% Mini-B and CLSE both generated minimum surface tensions <1 mN/m on 10 successive cycles of compression/expansion at quasi-static and dynamic rates. Conclusions These results show that DEPN-8 and 1.5% Mini-B form an interactive binary molecular mixture with very high surface activity and the ability to resist degradation by phospholipases in inflammatory lung injury. These characteristics are promising for the development of related fully-synthetic lipid/peptide exogenous surfactants for treating diseases of surfactant deficiency or dysfunction.
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Affiliation(s)
- Frans J Walther
- Los Angeles Biomedical Research Institute, Harbor-University of California at Los Angeles Medical Center, Torrance, California, United States of America.
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18
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Bakshi MS, Zhao L, Smith R, Possmayer F, Petersen NO. Metal nanoparticle pollutants interfere with pulmonary surfactant function in vitro. Biophys J 2007; 94:855-68. [PMID: 17890383 PMCID: PMC2186259 DOI: 10.1529/biophysj.107.106971] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Reported associations between air pollution and pulmonary and cardiovascular diseases prompted studies on the effects of gold nanoparticles (Au NP) on pulmonary surfactant function. Low levels (3.7 mol % Au/lipid, 0.98% wt/wt) markedly inhibited adsorption of a semisynthetic pulmonary surfactant (dipalmitoyl-phosphatidylcholine (DPPC)/palmitoyl-oleoyl-phosphatidylglycerol/surfactant protein B (SP-B); 70:30:1 wt %). Au NP also impeded the surfactant's ability to reduce surface tension (gamma) to low levels during film compression and to respread during film expansion. Transmission electron microscopy showed that Au NP generated by a seed-growth method were spherical with diameters of approximately 15 nm. Including palmitoyl-oleoyl-phosphatidylglycerol appeared to coat the NP with at least one lipid bilayer but did not affect NP shape or size. Similar overall observations occurred with dimyristoyl phosphatidylglycerol. Dipalmitoyl-phosphatidylglycerol was less effective in NP capping, although similar sized NP were formed. Including SP-B (1% wt/wt) appears to induce the formation of elongated strands of interacting threads with the fluid phosphatidylglycerols (PG). Including DPPC resulted in formation of aggregated, less spherical NP with a larger size distribution. With DPPC, strand formation due to SP-B was not observed. Agarose gel electrophoresis studies demonstrated that the aggregation induced by SP-B blocked migration of PG-coated NP. Migration was also influenced by the fluidity of the PGs. It is concluded that Au NP can interact with and sequester pulmonary surfactant phospholipids and, if inhaled from the atmosphere, could impede pulmonary surfactant function in the lung.
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Affiliation(s)
- Mandeep Singh Bakshi
- Department of Obstetrics and Gynaecology, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
- Department of Biochemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
- Department of Chemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
- Department of Chemistry, Guru Nanak Dev University, Amritsar, India
| | - Lin Zhao
- Department of Obstetrics and Gynaecology, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
| | - Ronald Smith
- Department of Biology, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
| | - Fred Possmayer
- Department of Obstetrics and Gynaecology, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
- Department of Biochemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
- Address reprint requests to Fred Possmayer, Depts. of Obs/Gyn and Biochemistry, Schulich School of Medicine and Dentistry, DSB 5009, London, ON, Canada N6A 5C1.
| | - Nils O. Petersen
- Department of Biochemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
- Department of Chemistry, University of Western Ontario, Schulich School of Medicine and Dentistry, London, Ontario, Canada
- National Institute for Nanotechnology, Edmonton, Alberta, Canada
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Erickson S, Schibler A, Numa A, Nuthall G, Yung M, Pascoe E, Wilkins B. Acute lung injury in pediatric intensive care in Australia and New Zealand: a prospective, multicenter, observational study. Pediatr Crit Care Med 2007; 8:317-23. [PMID: 17545931 DOI: 10.1097/01.pcc.0000269408.64179.ff] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Acute lung injury (ALI) is poorly defined in children. The objective of this prospective study was to clarify the incidence, demographics, management strategies, outcome, and mortality predictors of ALI in children in Australia and New Zealand. DESIGN Multicenter prospective study during a 12-month period. SETTING Intensive care unit. PATIENTS All children admitted to intensive care and requiring mechanical ventilation were screened daily for development of ALI based on American-European Consensus Conference guidelines. Identified patients were followed for 28 days or until death or discharge. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS There were 117 cases of ALI during the study period, giving a population incidence of 2.95/100,000 <16 yrs. ALI accounted for 2.2% of pediatric intensive care unit admissions. Mortality was 35% for ALI, and this accounted for 30% of all pediatric intensive care unit deaths during the study period. Significant preadmission risk factors for mortality were chronic disease, older age, and immunosuppression. Predictors of mortality during admission were ventilatory requirements (peak inspiratory pressures, mean airway pressure, positive end-expiratory pressure) and indexes of respiratory severity on day 1 (Pao2/Fio2 ratio and oxygenation index). Higher maximum and median tidal volumes were associated with reduced mortality, even when corrected for severity of lung disease. Development of single and multiple organ failure was significantly associated with mortality. CONCLUSIONS ALI in children is uncommon but has a high mortality rate. Risk factors for mortality are easily identified. Ventilatory variables and indexes of lung severity were significantly associated with mortality.
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Affiliation(s)
- Simon Erickson
- Pediatric Intensive Care Units at Princess Margaret Hospital for Children, Perth, WA, Australia.
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20
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Ji Y, Liu C, Pei YY. Artificial pulmonary surfactant as a carrier for intratracheally instilled insulin. Acta Pharmacol Sin 2007; 28:744-50. [PMID: 17439732 DOI: 10.1111/j.1745-7254.2007.00513.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
AIM The relative bioavailabilities and effects on lung injury alleviation of 4 insulin- artificial pulmonary surfactant (INS-APS) preparations were studied in normal rats. The relationship between the minimal surface tension (Gamma(min )) of INS-APS and the absorption of insulin was also investigated. METHODS Four formulations of APS [1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)/lecithin/palmitic acid (PA), DPPC/1-hexadecanol (Hex)/tyloxapol (Tyl), DPPC/L-alpha-phosphatidyl-DL-glycerol sodium salt (PG), DPPC/Tyl] were prepared by thin-film sonication method and direct sonication. The Gamma(min ) of 4 APS dispersions was examined with and without INS by pulsating with a bubble surface tensiometer. In vivo experiments were performed in which serum glucose change and the insulin level were measured by an enzymatic glucose reagent kit and a radioimmunology assay kit after IT to rats. The reduction in lung injury by INS-APS following 7 d of consecutive administration was evaluated by the pulmonary edema index (the weight ratio of wet lung to dry lung) and histopathology examination. RESULTS The Gamma(min ) of all APS dispersions were below 10 mN/m. There was no significant difference (P> 0.05) between the Gamma(min ) of APS and the corresponding INS-APS. In vivo experiments showed a significant glucose level decrease and insulin absorption increase (P< 0.05) in the presence of APS, compared to the insulin solution alone. From the results, we found that the pulmonary edema index values of all the INSAPS groups were significant lower (P< 0.05) than that of the insulin solution group, and there were no significant differences (P> 0.05) between INS/DPPC/Tyl, INS/ DPPC/PG, and the control group. The pulmonary edema indices and histopathological observation indicated that INS-APS could alleviate lung injury. CONCLUSION The most potent hypoglycemic effect and insulin absorption increase in this study were obtained with INS/DPPC/Tyl. According to the results, there was a linear correlation between the Gamma(min ) and relative bioavailability of INS-APS, suggesting a possible effect of the Gamma(min ) of carriers on the in vivo absorption of insulin. APS, DPPC/Tyl, and DPPC/PG dispersions might be the most efficient insulin pulmonary delivery carriers in achieving a lower Gamma(min ), enhancing insulin absorption, and decreasing lung injury.
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Affiliation(s)
- Ying Ji
- Department of Pharmaceutics, School of Pharmacy, Fudan University, Shanghai 200032, China
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21
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Anzueto A, Guntapalli K. Adjunctive therapy to mechanical ventilation: surfactant therapy, liquid ventilation, and prone position. Clin Chest Med 2007; 27:637-54; abstract ix. [PMID: 17085252 DOI: 10.1016/j.ccm.2006.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Acute lung injury and acute respiratory distress syndrome are associated with significant morbidity and mortality in critically ill patients. Although lung protective mechanical ventilation is the only therapy shown to reduce mortality and development of organ failure, several biologic pathways have been identified and provided an opportunity for therapeutic interventions. No pharmacologic or adjunctive treatments are available. Clinical studies demonstrated that prone position results in significant and clinically relevant improvement in oxygenation and ventilation, which persist when patients are returned to supine position; the beneficial response is not limited to patients turned early in disease course. Few complications are associated with prone ventilation. Clinical experience suggests that prone ventilation may protect the lung from potential detrimental effects of mechanical ventilation. Further studies are needed.
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Affiliation(s)
- Antonio Anzueto
- University of Texas Health Science Center, San Antonio, TX 78229, USA.
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22
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Notter RH, Wang Z, Wang Z, Davy JA, Schwan AL. Synthesis and surface activity of diether-linked phosphoglycerols: Potential applications for exogenous lung surfactants. Bioorg Med Chem Lett 2007; 17:113-7. [PMID: 17055273 DOI: 10.1016/j.bmcl.2006.09.083] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Revised: 09/24/2006] [Accepted: 09/27/2006] [Indexed: 10/24/2022]
Abstract
The synthesis of three phosphoglycerols is described, one of which contains the previously unknown phosphonoglycerol headgroup. The surface tension-lowering capabilities of synthetic lung surfactant mixtures containing the PG analogs were measured on the pulsating bubble surfactometer and compared to known controls. The PG-containing mixtures exhibited superior surface tension-lowering properties indicating the significant potential of these analogs as components in synthetic exogenous lung surfactants.
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Affiliation(s)
- Robert H Notter
- Department of Pediatrics, University of Rochester, Rochester, NY 14642, USA
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Davidson WJ, Dorscheid D, Spragg R, Schulzer M, Mak E, Ayas NT. Exogenous pulmonary surfactant for the treatment of adult patients with acute respiratory distress syndrome: results of a meta-analysis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2006; 10:R41. [PMID: 16542488 PMCID: PMC1550886 DOI: 10.1186/cc4851] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Revised: 02/09/2006] [Accepted: 02/13/2006] [Indexed: 01/11/2023]
Abstract
INTRODUCTION The purpose of this study was to perform a systematic review and meta-analysis of exogenous surfactant administration to assess whether this therapy may be useful in adult patients with acute respiratory distress syndrome. METHODS We performed a computerized literature search from 1966 to December 2005 to identify randomized clinical trials. The primary outcome measure was mortality 28-30 days after randomization. Secondary outcome measures included a change in oxygenation (PaO2:FiO2 ratio), the number of ventilation-free days, and the mean duration of ventilation. Meta-analysis was performed using the inverse variance method. RESULTS Two hundred and fifty-one articles were identified. Five studies met our inclusion criteria. Treatment with pulmonary surfactant was not associated with reduced mortality compared with the control group (odds ratio 0.97; 95% confidence interval (CI) 0.73, 1.30). Subgroup analysis revealed no difference between surfactant containing surface protein or not - the pooled odds ratio for mortality was 0.87 (95% CI 0.48, 1.58) for trials using surface protein and the odds ratio was 1.08 (95% CI 0.72, 1.64) for trials without surface protein. The mean difference in change in the PaO2:FiO2 ratio was not significant (P = 0.11). There was a trend for improved oxygenation in the surfactant group (pooled mean change 13.18 mmHg, standard error 8.23 mmHg; 95% CI -2.95, 29.32). The number of ventilation-free days and the mean duration of ventilation could not undergo pooled analysis due to a lack of sufficient data. CONCLUSION Exogenous surfactant may improve oxygenation but has not been shown to improve mortality. Currently, exogenous surfactant cannot be considered an effective adjunctive therapy in acute respiratory distress syndrome.
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Affiliation(s)
- Warren J Davidson
- Department of Medicine University of British Columbia, Vancouver, British Columbia, Canada.
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Mills PC, Chen Y, Hills YC, Hills BA. Comparison of surfactant lipids between pleural and pulmonary lining fluids. Pulm Pharmacol Ther 2006; 19:292-6. [PMID: 16168690 DOI: 10.1016/j.pupt.2005.08.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Revised: 08/01/2005] [Accepted: 08/03/2005] [Indexed: 11/20/2022]
Abstract
Saturated phospholipids (PCs), particularly dipalmitoylphosphatidylcholine (DPPC), predominate in surfactant lining the alveoli, although little is known about the relationship between saturated and unsaturated PCs on the outer surface of the lung, the pleura. Seven healthy cats were anesthetized and a bronchoalveolar lavage (BAL) was performed, immediately followed by a pleural lavage (PL). Lipid was extracted from lavage fluid and then analyzed for saturated, primarily dipalmitoylphosphatidylcholine (DPPC), and unsaturated PC species using high-performance liquid chromatography (HPLC) with combined fluorescence and ultraviolet detection. Dilution of epithelial lining fluid (ELF) in lavage fluids was corrected for using the urea method. The concentration of DPPC in BAL fluid (85.3+/-15.7 microg/mL) was significantly higher (P=0.021) than unsaturated PCs ( approximately 40 microg/mL). However, unsaturated PCs ( approximately 34 microg/mL), particularly stearoyl-linoleoyl-phosphatidylcholine (SLPC; 17.4+/-6.8), were significantly higher (P=0.021) than DPPC (4.3+/-1.8 microg/mL) in PL fluid. These results show that unsaturated PCs appear functionally more important in the pleural cavity, which may have implications for surfactant replenishment following pleural disease or thoracic surgery.
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Affiliation(s)
- P C Mills
- School of Veterinary Science, University of Queensland, Brisbane, Qld 4072, Australia.
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Vreugdenhil HA, Lachmann B, Haitsma JJ, Zijlstra J, Heijnen CJ, Jansen NJ, van Vught AJ. Exogenous surfactant restores lung function but not peripheral immunosuppression in ventilated surfactant-deficient rats. Exp Lung Res 2006; 32:1-14. [PMID: 16809217 DOI: 10.1080/01902140600575006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The authors have previously shown that mechanical ventilation can result in increased pulmonary inflammation and suppressed peripheral leukocyte function. In the present study the effect of surfactant therapy on pulmonary inflammation and peripheral immune function in ventilated surfactant-deficient rats was assessed. Surfactant deficiency was induced by repeated lung lavage, treated rats with surfactant or left them untreated, and ventilated the rats during 2 hours. Nonventilated rats served as healthy control group. Expression of macrophage inflammatory protein (MIP)-2 was measured in bronchoalveolar lavage (BAL), interleukin (IL)-1beta, and heat shock protein 70 (HSP70) were measured in total lung homogenates. Outside the lung phytohemagglutinin (PHA)-induced lymphocyte proliferation, interferon (IFN)-gamma and IL-10 production, and natural killer activity were measured in splenocytes. After 2 hours of mechanical ventilation, expression of MIP-2, IL-1beta, and HSP70 increased significantly in the lungs of surfactant-deficient rats. Outside the lung, mitogen-induced proliferation and production of IFN-gamma and IL-10 reduced significantly. Only natural killer cell activity remained unaffected. Surfactant treatment significantly improved lung function, but could not prevent increased pulmonary expression of MIP-2, IL-1beta, and HSP70 and decreased peripheral mitogen-induced lymphocyte proliferation and IFN-gamma and IL-10 production in vitro. In conclusion, 2 hours of mechanical ventilation resulted in increased lung inflammation and partial peripheral leukocyte suppression in surfactant-deficient rats. Surfactant therapy ameliorated lung function but could not prevent or restore peripheral immunosuppression. The authors postulate that peripheral immunosuppression may occur in ventilated surfactant deficient patients, which may enhance susceptibility for infections.
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Affiliation(s)
- Harriet A Vreugdenhil
- Pediatric Intensive Care Unit, and Laboratory for Psycho-Neuroimmunology, University Medical Center Utrecht, Utrecht, The Netherlands
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Ramanathan R. Surfactant therapy in preterm infants with respiratory distress syndrome and in near-term or term newborns with acute RDS. J Perinatol 2006; 26 Suppl 1:S51-6; discussion S63-4. [PMID: 16625226 PMCID: PMC7104450 DOI: 10.1038/sj.jp.7211474] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many different surfactant preparations derived from animal sources, as well as synthetic surfactants, are available for the treatment of preterm infants with respiratory distress syndrome (RDS). Natural, modified surfactants containing surfactant-associated proteins appear to be more effective than non-protein-containing synthetic surfactants. Comparative trials with poractant alfa at a higher initial dose of 200 mg/kg appear to be associated with rapid weaning of FiO2, less need for additional doses, and decreased mortality in infants <32 weeks gestation when compared with beractant. Early rescue (<30 min of age) surfactant therapy is an effective method to minimize over treatment of some preterm infants who may not develop RDS. Surfactant therapy followed by rapid extubation to nasal ventilation appears to be more beneficial than continued mechanical ventilation. In near-term or term newborns with acute RDS, surfactant therapy has been shown to be 70% effective in improving respiratory failure.
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Affiliation(s)
- R Ramanathan
- Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, USA.
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Ritter C, da Cunha AA, Echer IC, Andrades M, Reinke A, Lucchiari N, Rocha J, Streck EL, Menna-Barreto S, Moreira JCF, Dal-Pizzol F. Effects of N-acetylcysteine plus deferoxamine in lipopolysaccharide-induced acute lung injury in the rat*. Crit Care Med 2006; 34:471-7. [PMID: 16424730 DOI: 10.1097/01.ccm.0000199069.19193.89] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Interventions that reduce the generation or the effects of reactive oxygen species exert controversial effects in animal models of lung injury, and these could be secondary to the pro-oxidant effects of antioxidants generally by their interaction with iron. We here describe the effects of N-acetylcysteine, deferoxamine, or both in the treatment of acute lung injury induced by intratracheal lipopolysaccharide injection. DESIGN Prospective, randomized, controlled experiment. SETTING Animal basic science laboratory. SUBJECTS Male Wistar rats, weighing 200-250 g. INTERVENTIONS Rats exposed intratracheally to lipopolysaccharide were treated with N-acetylcysteine (20 mg/kg subcutaneously 3, 6, and 12 hrs after lipopolysaccharide instillation), deferoxamine (20 mg/kg subcutaneously 3 hrs after lipopolysaccharide instillation), N-acetylcysteine (20 mg/kg, 3, 6, and 12 hrs after lipopolysaccharide instillation) plus deferoxamine (20 mg/kg 3 hrs after lipopolysaccharide instillation), or vehicle. MEASUREMENTS AND MAIN RESULTS Acute lung injury was induced by intratracheal instillation of lipopolysaccharide in Wistar rats. The animals were randomly divided into five groups: group 1, control with instillation of isotonic saline; group 2, lipopolysaccharide treated with saline; group 3, lipopolysaccharide treated with N-acetylcysteine; group 4, lipopolysaccharide treated with deferoxamine; and group 5, lipopolysaccharide treated with N-acetylcysteine plus deferoxamine. Several times after lipopolysaccharide instillation, the rats were killed and a bronchoalveolar lavage was performed to determine thiobarbituric acid reactive species, protein carbonyls, superoxide dismutase and catalase activities, mitochondrial superoxide production (oxidative stress variables), the degree of the alveolar-capillary membrane compromise, and inflammatory infiltration. Samples from the lung were isolated and assayed for oxidative stress variables or histopathologic analyses. N-acetylcysteine plus deferoxamine decreased bronchoalveolar lavage fluid protein, inflammatory cells, oxidative damage variables, and proinflammatory cytokines. N-acetylcysteine plus deferoxamine treatment significantly attenuated lung oxidative damage, mitochondrial superoxide production, and histopathologic alterations after lipopolysaccharide instillation. CONCLUSIONS Our data provide the first experimental demonstration that N-acetylcysteine plus deferoxamine decreases oxidative stress and mitochondrial dysfunction and limits inflammatory response and alveolar pathology induced by lipopolysaccharide in the rat.
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Affiliation(s)
- Cristiane Ritter
- Centro de Estudos em Estresse Oxidativo, Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Dehority W, Lu KW, Clements J, Goerke J, Pittet JF, Allen L, Taeusch HW. Polyethylene glycol-surfactant for lavage lung injury in rats. Pediatr Res 2005; 58:913-8. [PMID: 16183815 DOI: 10.1203/01.pdr.0000182581.39561.01] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Addition of ionic and nonionic water-soluble polymers to pulmonary surfactants in the presence of inactivating substances prevents surfactant inactivation in vitro and improves lung function in several models of lung injury. However, a recent report found opposite effects when surfactant plus polyethylene glycol (PEG) was used to treat lung injury caused by saline lung lavage. Therefore, we examined the reasons why the polymer effect is less evident in the saline lung lavage lung injury model. We treated rats with lavage lung injury with a commercial lung surfactant extract derived from bovine lung (Survanta) with or without addition of PEG. Groups treated with Survanta + PEG had significantly higher static post mortem lung volumes than groups treated with Survanta. However, groups treated with Survanta + PEG had more tracheal fluid and no significant benefit in arterial oxygenation compared with the group treated with Survanta, despite our use of measures to reduce pulmonary edema. Measurements after intravascular injections of (125)I-labeled albumin confirmed that addition of PEG increased extravascular lung water and that this effect is mitigated by furosemide. We conclude that surfactant + PEG mixtures are less effective in lavage injury than in other forms of lung injury because of increased extravascular lung water.
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Affiliation(s)
- Walter Dehority
- Department of Pediatrics, San Francisco General Hospital/University of California-San Francisco, San Francisco, California 94110, USA
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30
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Kneyber MCJ, Plötz FB, Kimpen JLL. Bench-to-bedside review: Paediatric viral lower respiratory tract disease necessitating mechanical ventilation--should we use exogenous surfactant? CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2005; 9:550-5. [PMID: 16356236 PMCID: PMC1414027 DOI: 10.1186/cc3823] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Treatment of infants with viral lower respiratory tract disease (LRTD) necessitating mechanical ventilation is mainly symptomatic. The therapeutic use of surfactant seems rational because significantly lower levels of surfactant phospholipids and proteins, and impaired capacity to reduce surface tension were observed among infants and young children with viral LRTD. This article reviews the role of pulmonary surfactant in the pathogenesis of paediatric viral LRTD. Three randomized trials demonstrated improved oxygenation and reduced duration of mechanical ventilation and paediatric intensive care unit stay in young children with viral LRTD after administration of exogenous surfactant. This suggest that exogenous surfactant is the first beneficial treatment for ventilated infants with viral LRTD. Additionally, in vitro and animal studies demonstrated that surfactant associated proteins SP-A and SP-D bind to respiratory viruses, play a role in eliminating these viruses and induce an inflammatory response. Although these immunomodulating effects are promising, the available data are inconclusive and the findings are unconfirmed in humans. In summary, exogenous surfactant in ventilated infants with viral LRTD could be a useful therapeutic approach. Its beneficial role in improving oxygenation has already been established in clinical trials, whereas the immunomodulating effects are promising but remain to be elucidated.
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Affiliation(s)
- Martin CJ Kneyber
- Department of Pediatric Intensive Care, VU University Medical Center, Amsterdam, The Netherlands
| | - Frans B Plötz
- Department of Pediatric Intensive Care, VU University Medical Center, Amsterdam, The Netherlands
| | - Jan LL Kimpen
- Department of Pediatrics, Wilhelmina Children's Hospital, Utrecht, The Netherlands
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Camamo JM, McCoy RH, Erstad BL. Retrospective evaluation of inhaled prostaglandins in patients with acute respiratory distress syndrome. Pharmacotherapy 2005; 25:184-90. [PMID: 15767234 DOI: 10.1592/phco.25.2.184.56952] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
STUDY OBJECTIVES To determine whether use of inhaled alprostadil (PGE 1 ) or epoprostenol (PGI 2 ) significantly improved oxygenation in patients with acute respiratory distress syndrome (ARDS), and to determine whether differences between the two drugs exist with regard to oxygenation, duration of mechanical ventilation and hospitalization, adverse effects, and survival. DESIGN Retrospective chart review. SETTING A 360-bed tertiary care teaching facility with medical and surgical intensive care units. PATIENTS Twenty-seven patients admitted to the hospital who received either PGI 2 or PGE 1 for a primary or secondary diagnosis of ARDS. MEASUREMENTS AND MAIN RESULTS Seventeen patients received inhaled PGE 1 and 10 received inhaled PGI 2 . There were no significant changes in the ratio of arterial partial pressure of oxygen (PaO 2 ):fraction of inspired oxygen (FiO 2 ) and in the PaO 2 , from baseline to any time point that was analyzed during treatment, for patients receiving either PGE 1 (p=0.2120 and 0.3399, respectively) or PGI 2 (p=0.1655 and 0.0784, respectively). CONCLUSION No statistically significant improvement in oxygenation was observed in patients receiving either PGE 1 or PGI 2 . In addition, no significant differences were found between the two prostaglandins for the variables studied. Until positive results from large, prospective studies are available, we recommend that these inhaled prostaglandins not be used to treat ARDS.
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Affiliation(s)
- James M Camamo
- Department of Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, Arizona, USA
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Abstract
Acute lung injury is a syndrome diagnosed clinically and is one of the most common causes of respiratory failure seen in the intensive care unit. A consensus definition of this and its more severe form, acute respiratory distress syndrome (ARDS), has allowed for better consistency in determining the epidemiology and facilitates consistent clinical trial design to better find therapies to treat or prevent it. Patients who present with ARDS usually show signs of tachpnea or dyspnea and have underlying conditions that promote inflammatory responses. The pathogenesis involves an inflammatory insult that eventually destroys the pulmonary capillary vasculature as well as alveoli. Pathophysiologically, the patient with ARDS may progress through as many as 3 phases: exudative, proliferative, and fibrotic. Treatment options can be either nonpharmacologic or pharmacologic and are limited. Ventilator strategies such as low-tidal-volume ventilation have improved outcomes in these patients, while corticosteroid use is not as established to provide morbidity or mortality benefit. Other therapies have been investigated with inconclusive or disappointing results for the treatment of this fatal syndrome.
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Affiliation(s)
- Brian S. Burleson
- Department of Pharmacy Practice, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas,
| | - Erik D. Maki
- Department of Pharmacy Practice, Texas Tech University Health Sciences Center, School of Pharmacy, Amarillo, Texas
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Bosma K, Fanelli V, Ranieri VM. Acute respiratory distress syndrome: update on the latest developments in basic and clinical research. Curr Opin Anaesthesiol 2005; 18:137-45. [PMID: 16534329 DOI: 10.1097/01.aco.0000162831.41097.6b] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE OF REVIEW Acute lung injury/acute respiratory distress syndrome is a common, serious condition affecting a heterogeneous population of critically ill patients. Other than low tidal volume ventilation, no specific therapy has improved survival. Understanding the epidemiology, pathogenesis, and lessons to be learned from previous clinical trials is necessary for the development of new therapies and the rational design of studies assessing their efficacy. RECENT FINDINGS Acute lung injury/acute respiratory distress syndrome occurs in 6-8% of the general intensive care unit population, with a mortality of 32-45%. A recent epidemiologic study found that multi-organ dysfunction, use of tidal volumes higher than 6 ml/kg, and high mean fluid balance were independent risks for mortality. Although high levels of inflammatory mediators are also markers for acute respiratory distress syndrome development and death, short courses of high-dose steroids are not effective in acute cases. The latest theory of biotrauma proposes cellular mechanisms by which mechanical ventilation incites a local and systemic inflammatory response; protective lung ventilation with low tidal volumes can attenuate this inflammation and injury to distal organs. Endogenous surfactant function is clearly impaired, but no commercially available surfactant preparation has been shown to reduce mortality. Results of trials to determine efficacy of steroids in late cases and optimal fluid management are pending. SUMMARY The results of recent clinical trials have raised more questions. Further study of the inflammatory response, surfactant regulation, and the cellular impact of mechanical ventilation should help to develop new therapies, target patients most likely to benefit, and identify appropriate timing of intervention.
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Affiliation(s)
- Karen Bosma
- Department of Anaesthesiology, University of Torino, Turin, Italy
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Surfactant metabolism: factors affecting lipid uptake in vivo and in vitro. ANAESTHESIA, PAIN, INTENSIVE CARE AND EMERGENCY MEDICINE — A.P.I.C.E. 2005. [PMCID: PMC7122009 DOI: 10.1007/88-470-0351-2_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Adhikari N, Burns KEA, Meade MO. Pharmacologic therapies for adults with acute lung injury and acute respiratory distress syndrome. Cochrane Database Syst Rev 2004; 2004:CD004477. [PMID: 15495113 PMCID: PMC6517021 DOI: 10.1002/14651858.cd004477.pub2] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Multiple pharmacologic treatments have been studied for acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). OBJECTIVES Our objective was to determine the effects of pharmacologic treatments on clinical outcomes in adults with ALI or ARDS. SEARCH STRATEGY We searched OVID versions of CENTRAL (The Cochrane Library Issue 3, 2003), MEDLINE (1966 to week 2, January 2004), EMBASE (1980 to week 4, 2004), CINAHL (1982 to week 2, January 2004), and HEALTHSTAR (1995 to December 2003); proceedings from four conferences (1994 to 2003); and bibliographies of review articles and included studies. SELECTION CRITERIA Randomized controlled trials of pharmacologic treatments compared to no therapy or placebo for established ALI or ARDS in adults admitted to an intensive care unit, with measurement of early mortality (primary outcome), late mortality, duration of mechanical ventilation, ventilator-free days to day 28, or adverse events. We excluded trials of nitric oxide, partial liquid ventilation, fluid and nutritional interventions, oxygen, and trials in other populations reporting outcomes in subgroups of patients with ALI or ARDS. DATA COLLECTION AND ANALYSIS Two reviewers independently screened titles and abstracts, rated studies for inclusion, extracted data and assessed methodologic quality of included studies. Disagreements were resolved by consensus in consultation with a third reviewer. For each pharmacologic therapy, we quantitatively pooled the results of studies using random effects models where permitted by the available data. We contacted study authors when clarification of the primary outcome was required. MAIN RESULTS Thirty three trials randomizing 3272 patients met our inclusion criteria. Pooling of results showed no effect on early mortality of prostaglandin E1 (seven trials randomizing 697 patients; relative risk [RR] 0.95, 95% confidence interval [CI] 0.77 to 1.17), N-acetylcysteine (five trials randomizing 239 patients; RR 0.89, 95% CI 0.65 to 1.21), early high-dose corticosteroids (two trials randomizing 187 patients; RR 1.12, 95% CI 0.72 to 1.74), or surfactant (nine trials randomizing 1441 patients; RR 0.93, 95% CI 0.77 to 1.12). Two interventions were beneficial in single small trials; corticosteroids given for late phase ARDS reduced hospital mortality (24 patients; RR 0.20, 95% CI 0.05 to 0.81), and pentoxifylline reduced one-month mortality (RR 0.67, 95% CI 0.47 to 0.95) in 30 patients with metastatic cancer and ARDS. Individual trials of nine additional interventions failed to show a beneficial effect on prespecified outcomes. REVIEWERS' CONCLUSIONS Effective pharmacotherapy for ALI and ARDS is extremely limited, with insufficient evidence to support any specific intervention.
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Affiliation(s)
- N Adhikari
- Critical Care Medicine and Medicine, Sunnybrook and Women's College Health Centre, 2075 Bayview Avenue, B7.04a, Toronto, M4N 3M5, Ontario, Canada.
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Bandi VD, Munnur U, Matthay MA. Acute lung injury and acute respiratory distress syndrome in pregnancy. Crit Care Clin 2004; 20:577-607. [PMID: 15388190 DOI: 10.1016/j.ccc.2004.05.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Acute respiratory failure can be the result of a variety of clinical conditions, such as congestive heart failure, pneumonia, pulmonary embolism, exacerbation of obstructive lung diseases, and acute respiratory distress syndrome (ARDS). This article focuses on developments related to acute lung injury and ARDS and reviews epidemiology, pathogenesis and therapeutic advances with an emphasis on the obstetric population. A brief discussion of tocolytic-induced pulmonary edema, preeclampsia, venous air embolism, and aspiration-related ARDS is included. Management of pregnant women with ARDS is outlined.
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Affiliation(s)
- Venkata D Bandi
- Section of Pulmonary and Critical Care Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
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Crimi E, Slutsky AS. Inflammation and the acute respiratory distress syndrome. Best Pract Res Clin Anaesthesiol 2004; 18:477-92. [PMID: 15212340 DOI: 10.1016/j.bpa.2003.12.007] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Acute respiratory distress syndrome (ARDS) is a clinical syndrome of non-cardiogenic pulmonary oedema associated with bilateral pulmonary infiltrates, stiff lungs and refractory hypoxaemia. ARDS is characterized by an explosive acute inflammatory response in the lung parenchyma, leading to alveolar oedema, decreased lung compliance and, ultimately, hypoxaemia. Although our understanding of the causes and pathophysiology of ARDS has increased, the mortality rate remains in the range of 30-50%. No major advances in pharmacological therapy have been achieved. Mechanical ventilation is the main therapeutic intervention in the management of ARDS. The only approach that has been shown to reduce the inflammatory response and mortality is the use of lung-protective ventilatory strategy with a low tidal volume and high positive-end expiratory pressure. This chapter will review the current state of the literature on the pathogenesis of ARDS and ventilatory and pharmacotherapy approaches to its management.
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Affiliation(s)
- Ettore Crimi
- Division of Respiratory Medicine, Department of Critical Care Medicine, St Michael's Hospital, University of Toronto, Toronto, Ont., Canada
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Abstract
Mechanical ventilation is the second most frequently performed therapeutic intervention after treatment for cardiac arrhythmias in intensive care units today. Countless lives have been saved with its use despite being associated with a greater than 30% in-hospital mortality rate. As life expectancies increase and people with chronic illnesses survive longer, artificial support with mechanical ventilation is also expected to rise. In one survey, over half of senior internal medicine residents reported their training on mechanical ventilation as inadequate, whereas the majority of critical care nurses reported having received no formal education on its use. Technological advances resulting in the availability of sleeker ventilators with graphic waveform displays and new modes of ventilation have challenged the bedside clinicians to incorporate this new data along with evidenced-based research into their daily practice. A review of current thoughts on mechanical ventilation and weaning is presented.
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Affiliation(s)
- Denise Fenstermacher
- Medical Intensive Care Unit, University of Illinois Medical Center at Chicago, Chicago, IL 60612, USA.
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Onarheim H, Vik V. Porcine surfactant (Curosurf) for acute respiratory failure after near-drowning in 12 year old. Acta Anaesthesiol Scand 2004; 48:778-81. [PMID: 15196112 DOI: 10.1111/j.0001-5172.2004.00406.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
This case report describes rapid and persistent improvement after one single dose of porcine surfactant (Curosurf) 0.5 ml/kg(-1) (40 mg/kg) intratracheally for adult respiratory distress syndrome (ARDS) with severe oxygenation failure 8 h after freshwater near-drowning in a 12-year-old girl.
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Affiliation(s)
- H Onarheim
- Department of Anaesthesia and Intensive Care, Haukeland University Hospital, Bergen, Norway.
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