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Rao JS, Pruett TL. Immunology of the transplanted cryopreserved kidney. Cryobiology 2023; 110:1-7. [PMID: 36640932 DOI: 10.1016/j.cryobiol.2023.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/28/2022] [Accepted: 01/10/2023] [Indexed: 01/13/2023]
Abstract
Transplantation has substituted dysfunctional organs with healthy organs from donors to significantly lower morbidity and mortality associated with end-stage organ disease. Since the advent of transplantation, the promise of functional replacement has attracted an exponential mismatch between organ supply and demand. Theoretical proposals to counter the increasing needs have either been to create a source through genetic engineering of porcine donors for xenotransplantation (with more potent immunosuppression protocols) or recreate one's organ in a pig using interspecies blastocyst complementation for exogenic organ transplantation (without immunosuppression). Another promising avenue has been organ banking through cryopreservation for transplantation. Although ice free preservation and acceptable early function following rewarming is critical for success in transplantation, the immunological response that predominantly defines short- and long-term graft survival has failed to captivate attention to date. It is well sorted that thermal and metabolic stress incurred at 4 °C during recovery and reperfusion of organs for clinical transplantation has varying impact on graft survival. Considering the magnitude of cellular imbalance and injury at sub-zero/ultralow temperatures in addition to the chemical toxicity of cryoprotective agents (CPA), it is essential to assess and address the immunological response associated following transplantation to maximize the success of cryopreservation.
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Affiliation(s)
- Joseph Sushil Rao
- Division of Solid Organ Transplantation, Department of Surgery, University of Minnesota, Minneapolis, MN, USA; Schulze Diabetes Institute, Department of Surgery, University of Minnesota, Minneapolis, MN, USA.
| | - Timothy L Pruett
- Division of Solid Organ Transplantation, Department of Surgery, University of Minnesota, Minneapolis, MN, USA.
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Zhao H, Alam A, Soo AP, George AJT, Ma D. Ischemia-Reperfusion Injury Reduces Long Term Renal Graft Survival: Mechanism and Beyond. EBioMedicine 2018; 28:31-42. [PMID: 29398595 PMCID: PMC5835570 DOI: 10.1016/j.ebiom.2018.01.025] [Citation(s) in RCA: 175] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 01/18/2018] [Accepted: 01/20/2018] [Indexed: 01/10/2023] Open
Abstract
Ischemia-reperfusion injury (IRI) during renal transplantation often initiates non-specific inflammatory responses that can result in the loss of kidney graft viability. However, the long-term consequence of IRI on renal grafts survival is uncertain. Here we review clinical evidence and laboratory studies, and elucidate the association between early IRI and later graft loss. Our critical analysis of previous publications indicates that early IRI does contribute to later graft loss through reduction of renal functional mass, graft vascular injury, and chronic hypoxia, as well as subsequent fibrosis. IRI is also known to induce kidney allograft dysfunction and acute rejection, reducing graft survival. Therefore, attempts have been made to substitute traditional preserving solutions with novel agents, yielding promising results. Ischaemia reperfusion injury (IRI) potentiates delayed renal graft function and causes reduction in renal graft survival IRI causes innate immune system activation, hypoxic injury, inflammation and graft vascular disease Reducing prolonged cold ischaemic time improves graft survival Novel protective strategies include mesenchymal stem cells, machine perfusion, and ex vivo preservation solution saturated with gas. Further studies are needed to investigate the long-term effects of novel ex vivo preservation agents
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Affiliation(s)
- Hailin Zhao
- Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea & Westminster Hospital, London, UK
| | - Azeem Alam
- Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea & Westminster Hospital, London, UK
| | - Aurelie Pac Soo
- Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea & Westminster Hospital, London, UK
| | | | - Daqing Ma
- Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea & Westminster Hospital, London, UK.
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Yuan Y, Alwis I, Wu MCL, Kaplan Z, Ashworth K, Bark D, Pham A, Mcfadyen J, Schoenwaelder SM, Josefsson EC, Kile BT, Jackson SP. Neutrophil macroaggregates promote widespread pulmonary thrombosis after gut ischemia. Sci Transl Med 2017; 9:eaam5861. [PMID: 28954929 DOI: 10.1126/scitranslmed.aam5861] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 05/02/2017] [Accepted: 08/21/2017] [Indexed: 11/02/2022]
Abstract
Gut ischemia is common in critically ill patients, promoting thrombosis and inflammation in distant organs. The mechanisms linking hemodynamic changes in the gut to remote organ thrombosis remain ill-defined. We demonstrate that gut ischemia in the mouse induces a distinct pulmonary thrombotic disorder triggered by neutrophil macroaggregates. These neutrophil aggregates lead to widespread occlusion of pulmonary arteries, veins, and the microvasculature. A similar pulmonary neutrophil-rich thrombotic response occurred in humans with the acute respiratory distress syndrome. Intravital microscopy during gut ischemia-reperfusion injury revealed that rolling neutrophils extract large membrane fragments from remnant dying platelets in multiple organs. These platelet fragments bridge adjacent neutrophils to facilitate macroaggregation. Platelet-specific deletion of cyclophilin D, a mitochondrial regulator of cell necrosis, prevented neutrophil macroaggregation and pulmonary thrombosis. Our studies demonstrate the existence of a distinct pulmonary thrombotic disorder triggered by dying platelets and neutrophil macroaggregates. Therapeutic targeting of platelet death pathways may reduce pulmonary thrombosis in critically ill patients.
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Affiliation(s)
- Yuping Yuan
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
- Heart Research Institute, Newtown, New South Wales 2042, Australia
- Charles Perkins Centre, University of Sydney, New South Wales 2006, Australia
| | - Imala Alwis
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
- Heart Research Institute, Newtown, New South Wales 2042, Australia
- Charles Perkins Centre, University of Sydney, New South Wales 2006, Australia
| | - Mike C L Wu
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
- Heart Research Institute, Newtown, New South Wales 2042, Australia
- Charles Perkins Centre, University of Sydney, New South Wales 2006, Australia
| | - Zane Kaplan
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
| | - Katrina Ashworth
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
| | - David Bark
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
| | - Alan Pham
- Department of Anatomical Pathology, Alfred Hospital, Prahran, Victoria 3181, Australia
| | - James Mcfadyen
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
| | - Simone M Schoenwaelder
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia
- Heart Research Institute, Newtown, New South Wales 2042, Australia
| | - Emma C Josefsson
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Benjamin T Kile
- Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
- Department of Anatomy and Developmental Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3168, Australia
| | - Shaun P Jackson
- Australian Centre for Blood Diseases, Alfred Medical and Research Education Precinct, Monash University, Melbourne, Victoria 3004, Australia.
- Heart Research Institute, Newtown, New South Wales 2042, Australia
- Charles Perkins Centre, University of Sydney, New South Wales 2006, Australia
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
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Fellner B, Rohla M, Jarai R, Smetana P, Freynhofer MK, Egger F, Zorn G, Weiss TW, Huber K, Geppert A. Activated protein C levels and outcome in patients with cardiogenic shock complicating acute myocardial infarction. EUROPEAN HEART JOURNAL-ACUTE CARDIOVASCULAR CARE 2016; 6:348-358. [DOI: 10.1177/2048872616637036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Barbara Fellner
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Miklos Rohla
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Rudolf Jarai
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Peter Smetana
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Matthias K Freynhofer
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Florian Egger
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Gerlinde Zorn
- Department of Internal Medicine II, Medical University of Vienna, Vienna, Austria
| | - Thomas W Weiss
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Kurt Huber
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
| | - Alexander Geppert
- 3rd Medical Department, Cardiology and Intensive Care Medicine, Wilhelminenhospital, Vienna, Austria
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Glodowski SD, Wagener G. New insights into the mechanisms of acute kidney injury in the intensive care unit. J Clin Anesth 2015; 27:175-80. [DOI: 10.1016/j.jclinane.2014.09.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 08/22/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
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de Miranda ML, Pereira SJ, Santos AOMT, Villela NR, Kraemer-Aguiar LG, Bouskela E. Milrinone attenuates arteriolar vasoconstriction and capillary perfusion deficits on endotoxemic hamsters. PLoS One 2015; 10:e0117004. [PMID: 25646813 PMCID: PMC4315607 DOI: 10.1371/journal.pone.0117004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 12/17/2014] [Indexed: 12/29/2022] Open
Abstract
Background and Objective Apart from its inotropic property, milrinone has vasodilator, anti-inflammatory and antithrombotic effects that could assist in the reversal of septic microcirculatory changes. This paper investigates the effects of milrinone on endotoxemia-related microcirculatory changes and compares them to those observed with the use of norepinephrine. Materials and Methods After skinfold chamber implantation procedures and endotoxemia induction by intravenous Escherichia coli lipopolysaccharide administration (2 mg.kg-1), male golden Syrian hamsters were treated with two regimens of intravenous milrinone (0.25 or 0.5 μg.kg-1.min-1). Intravital microscopy of skinfold chamber preparations allowed quantitative analysis of microvascular variables. Macro-hemodynamic, biochemical, and hematological parameters and survival rate were also analyzed. Endotoxemic non-treated animals, endotoxemic animals treated with norepinephrine (0.2 μg.kg-1.min-1), and non-endotoxemic hamsters served as controls. Results Milrinone (0.5 μg.kg-1.min-1) was effective in reducing lipopolysaccharide-induced arteriolar vasoconstriction, capillary perfusion deficits, and inflammatory response, and in increasing survival. Norepinephrine treated animals showed the best mean arterial pressure levels but the worst functional capillary density values among all endotoxemic groups. Conclusion Our data suggests that milrinone yielded protective effects on endotoxemic animals’ microcirculation, showed anti-inflammatory properties, and improved survival. Norepinephrine did not recruit the microcirculation nor demonstrated anti-inflammatory effects.
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Affiliation(s)
- Marcos Lopes de Miranda
- Department of Internal Medicine, Division of Critical Care, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro, RJ, Brazil
- * E-mail:
| | - Sandra J. Pereira
- Pediatric Cardiac Intensive Care Unit, Perinatal Barra, Rio de Janeiro, RJ, Brazil
| | - Ana O. M. T. Santos
- Institute Fernandes Figueira, Oswaldo Cruz Foundation—FIOCRUZ, Rio de Janeiro, RJ, Brazil
| | - Nivaldo R. Villela
- Department of Surgery, Division of Anesthesiology, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro, RJ, Brazil
| | - Luiz Guilherme Kraemer-Aguiar
- Department of Internal Medicine, Division of Endocrinology, Faculty of Medical Sciences, Rio de Janeiro State University, Rio de Janeiro, RJ, Brazil
| | - Eliete Bouskela
- Laboratory for Clinical and Experimental Research in Vascular Biology—BioVasc, Biomedical Center, Rio de Janeiro State University, Rio de Janeiro, RJ, Brazil
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Villela NR, dos Santos AOMT, de Miranda ML, Bouskela E. Fluid resuscitation therapy in endotoxemic hamsters improves survival and attenuates capillary perfusion deficits and inflammatory responses by a mechanism related to nitric oxide. J Transl Med 2014; 12:232. [PMID: 25151363 PMCID: PMC4158098 DOI: 10.1186/s12967-014-0232-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 08/15/2014] [Indexed: 12/21/2022] Open
Abstract
Background Relative hypovolemia is frequently found in early stages of severe sepsis and septic shock and prompt and aggressive fluid therapy has become standard of care improving tissue perfusion and patient outcome. This paper investigates the role of the nitric oxide pathway on beneficial microcirculatory effects of fluid resuscitation. Methods After skinfold chamber implantation procedures and endotoxemia induction by intravenous Escherichia coli lipopolysaccharide administration (2 mg.kg−1), male golden Syrian hamsters were fluid resuscitated and then sequentially treated with L-Nω-Nitroarginine and L-Arginine hydrochloride (LPS/FR/LNNA group). Intravital microscopy of skinfold chamber preparations allowed quantitative analysis of microvascular variables including venular leukocyte rolling and adhesion. Macro-hemodynamic, biochemical and hematological parameters as well as survival rate were also evaluated. Endotoxemic hamsters treated with fluid therapy alone (LPS/FR group) and non-treated animals (LPS group) served as controls. Results Fluid resuscitation was effective in reducing lipopolysaccharide-induced microcirculatory changes. After 3 hours of lipopolysaccharide administration, non-fluid resuscitated animals (LPS group) had the lowest functional capillary density (1% from baseline for LPS group vs. 19% for LPS/FR one; p <0.05). At the same time point, arteriolar mean internal diameter was significantly wider in LPS/FR group than in LPS one (100% vs. 50% from baseline). Fluid resuscitation also reduced leukocyte-endothelium interactions and sequestration (p <0.05 for LPS vs. LPS/FR group) and increased survival (median survival time: 2 and 5.5 days for LPS and LPS/FR groups, respectively; p <0.05). Nitric oxide synthase inhibition prevented these protective effects, while L-Arginine administration markedly restored many of them. Conclusion Our results suggest that the underlying mechanism of fluid therapy is the restoration of nitric oxide bioavailability, because inhibition of NOS prevented many of its beneficial effects. Nevertheless, further investigations are required in experimental models closer to conditions of human sepsis to confirm these results.
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Affiliation(s)
- Nivaldo Ribeiro Villela
- Department of Surgery, Division of Anesthesiology, Faculty of Medical Sciences, Rio de Janeiro State University, Boulevard 28 de Setembro, Rio de Janeiro, 77 - Vila Isabel, 20,551-030, RJ, Brazil.
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8
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From macrohemodynamic to the microcirculation. Crit Care Res Pract 2013; 2013:892710. [PMID: 23509621 PMCID: PMC3600213 DOI: 10.1155/2013/892710] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 01/22/2013] [Accepted: 01/28/2013] [Indexed: 01/20/2023] Open
Abstract
ICU patients need a prompt normalization of macrohemodynamic parameters. Unfortunately, this optimization sometimes does not protect patients from organ failure development. Prevention or treatment of organ failure needs another target to be pursued: the microcirculatory restoration. Microcirculation is the ensemble of vessels of maximum 100 μm in diameter. Nowadays the Sidestream Dark Field (SDF) imaging technique allows its bedside investigation and a recent round-table conference established the criteria for its evaluation. First, microcirculatory derangements have been studied in sepsis: they are mainly characterized by a reduction of vessel density, an alteration of flow, and a heterogeneous distribution of perfusion. Endothelial malfunction and glycocalyx rupture were proved to be the main reasons for the observed microthrombi, capillary leakage, leukocyte rolling, and rouleaux phenomenon, even if further studies are necessary for a better explanation. Therapeutic approaches targeting microcirculation are under investigation. Microcirculatory alterations have been recently demonstrated in other diseases such as hypovolemia and cardiac failure but this issue still needs to be explored. The aim of this paper is to gather the already known information, focus the reader's attention on the importance of microvascular physiopathology in critical illness, and prompt him to actively participate to achieve a more comprehensive understanding of the issue.
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De Backer D, Donadello K, Cortes DO. Monitoring the microcirculation. J Clin Monit Comput 2012; 26:361-6. [PMID: 22833180 DOI: 10.1007/s10877-012-9383-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 07/11/2012] [Indexed: 01/07/2023]
Abstract
One of the main goals of hemodynamic support is to preserve tissue perfusion. However issue perfusion is related more to microvascular perfusion than aortic blood flow. Monitoring the microcirculation has long been difficult. Recent technologic advances have made feasible monitoring of the microcirculation at bedside of critically ill patients. In this review, we will discuss the relevance of the various tools available to monitor the microcirculation. Videomicroscopic devices such as sidestream darkfield imaging are the most appropriate techniques to evaluate the microcirculation, taking into account the heterogeneous aspect of diseased microcirculation, as in sepsis. The microcirculation can also be indirectly assessed by measuring tissue PCO2. Transcutaneous PCO2 measurement at ear lobe is particularly promising. Finally, near infrared spectroscopy can also provide interesting information, especially using vascular occlusion tests which reactivity of the microcirculation to a transient hypoxic insult. These different devices have provided important data helping us to better understand the pathophysiology of sepsis and multiple organ failure.
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Affiliation(s)
- Daniel De Backer
- Department of Intensive Care, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium.
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10
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Fertmann JM, Arbogast HP, Illner WD, Tarabichi A, Dieterle C, Land W, Jauch KW, Hoffmann JN. Antithrombin therapy in pancreas retransplantation and pancreas-after-kidney/pancreas-transplantation-alone patients. Clin Transplant 2011; 25:E499-508. [DOI: 10.1111/j.1399-0012.2011.01472.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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11
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Schildberg FW, Hoffmann JN. [Scientific acquisition of knowledge in operative medicine. The importance of intensive care medicine]. Med Klin Intensivmed Notfmed 2011; 106:34-40. [PMID: 21975840 DOI: 10.1007/s00063-011-0024-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 01/17/2011] [Accepted: 01/17/2011] [Indexed: 11/29/2022]
Abstract
The forms of treatment in intensive care medicine and the medicinal and instrumental equipment for maintaining the circulation, pulmonary and renal functions as well as surveillance for recognition of life-threatening arrhythmias or multiorgan failure have experienced an enormous development in recent decades. Survival of traumatized or critically ill patients has been substantially improved. Due to these developments surgeons are confronted with new patterns of diseases which necessitate the development of new operative measures. This article gives a review of the most important changes in operative medicine (e.g. traumatology and vascular surgery) which can essentially be attributed to experience and success in intensive care medicine.
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Affiliation(s)
- F W Schildberg
- Chirurgische Klinik und Poliklinik, Klinikum der Universität München, Campus Großhadern, München, Deutschland
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Christersson C, Oldgren J, Wallentin L, Siegbahn A. Treatment with an oral direct thrombin inhibitor decreases platelet activity but increases markers of inflammation in patients with myocardial infarction. J Intern Med 2011; 270:215-23. [PMID: 21255134 DOI: 10.1111/j.1365-2796.2011.02354.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Thrombin has a role not only in the coagulation process but also in inflammatory responses. Oral direct thrombin inhibitors (DTIs) are currently being evaluated in patients with thromboembolic diseases. OBJECTIVE To investigate whether an oral DTI affects markers for platelet and inflammatory activity after myocardial infarction (MI). METHODS A total of 518 patients with MI were randomly assigned to ximelagatran treatment (four different dose groups) in combination with aspirin, or aspirin alone for 6 months. The levels of soluble (s) P-selectin, soluble tissue factor, C-reactive protein (CRP), interleukin (IL)-10 and IL-18 were analysed in serial blood samples. RESULTS sP-selectin concentration increased after 1 week and persisted at an elevated level for 6 months in all study groups (P < 0.001). In the two highest ximelagatran dose groups, there was a reduced increase in sP-selectin compared to treatment with lower doses of ximelagatran and aspirin alone (P = 0.01 and P = 0.002, respectively). IL-18 levels did not change in the aspirin alone treatment group. By contrast, there was an elevation in IL-18 level in the lower and higher ximelagatran dose groups after 6 months (P = 0.006 and P < 0.001, respectively). Ximelagatran increased IL-10 levels (P = 0.002) and reduced the decrease in CRP levels after 6 months compared to treatment with aspirin alone (P = 0.002). CONCLUSION A persistent elevation of platelet activity is found in patients with a recent MI after the cessation of acute antithrombotic treatment, and the addition of an oral DTI at higher doses decreases the activity. By contrast, long-term treatment with a DTI increases the levels of several markers of inflammation. Further studies with prolonged exposure of oral DTIs are needed for evaluation of the effect on inflammatory processes and to determine whether these agents influence clinical outcomes.
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Affiliation(s)
- C Christersson
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
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13
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The role of activated neutrophils in the early stage of equine laminitis. Vet J 2011; 189:27-33. [DOI: 10.1016/j.tvjl.2010.06.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 06/03/2010] [Accepted: 06/11/2010] [Indexed: 12/26/2022]
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15
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Gehrig SM, Lynch GS. Emerging drugs for treating skeletal muscle injury and promoting muscle repair. Expert Opin Emerg Drugs 2011; 16:163-82. [DOI: 10.1517/14728214.2010.524743] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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16
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Effects of Microbubbles and Ultrasound on the Microcirculation: Observation on the Hamster Cheek Pouch. J Am Soc Echocardiogr 2010; 23:1323-30. [DOI: 10.1016/j.echo.2010.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Indexed: 11/21/2022]
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17
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Guan YF, Pritts TA, Montrose MH. Ischemic post-conditioning to counteract intestinal ischemia/reperfusion injury. World J Gastrointest Pathophysiol 2010; 1:137-43. [PMID: 21607154 PMCID: PMC3097957 DOI: 10.4291/wjgp.v1.i4.137] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 09/29/2010] [Accepted: 10/06/2010] [Indexed: 02/06/2023] Open
Abstract
Intestinal ischemia is a severe disorder with a variety of causes. Reperfusion is a common occurrence during treatment of acute intestinal ischemia but the injury resulting from ischemia/reperfusion (IR) may lead to even more serious complications from intestinal atrophy to multiple organ failure and death. The susceptibility of the intestine to IR-induced injury (IRI) appears from various experimental studies and clinical settings such as cardiac and major vascular surgery and organ transplantation. Whereas oxygen free radicals, activation of leukocytes, failure of microvascular perfusion, cellular acidosis and disturbance of intracellular homeostasis have been implicated as important factors in the pathogenesis of intestinal IRI, the mechanisms underlying this disorder are not well known. To date, increasing attention is being paid in animal studies to potential pre- and post-ischemia treatments that protect against intestinal IRI such as drug interference with IR-induced apoptosis and inflammation processes and ischemic pre-conditioning. However, better insight is needed into the molecular and cellular events associated with reperfusion-induced damage to develop effective clinical protection protocols to combat this disorder. In this respect, the use of ischemic post-conditioning in combination with experimentally prolonged acidosis blocking deleterious reperfusion actions may turn out to have particular clinical relevance.
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Ping C, Yongping Z, Minmin Q, Weiyan Y, Yaozong Y. Activated protein C improves the severity of severe acute pancreatitis via up-regulating the expressions of endothelial cell protein C receptor and thrombomodulin. Dig Dis Sci 2010; 55:1599-609. [PMID: 19680809 DOI: 10.1007/s10620-009-0909-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Accepted: 07/05/2009] [Indexed: 12/09/2022]
Abstract
BACKGROUND AND AIMS Activated protein C (APC) is increasingly understood to have diverse regulatory functions in inflammation. However, the exact mechanism of action remains unclear in severe acute pancreatitis (SAP). The aim of this study was to demonstrate the effects of APC on expressions of thrombomodulin (TM) and endothelial cell protein C receptor (EPCR), and its subsequent effect on the severity of SAP. METHODS Sprague-Dawley rats were randomly divided into four groups. The rats were given intravenous injections of APC (50, 10 microg/kg, respectively, treated groups) or saline (SAP group) just before induction of SAP. One group of rats underwent only sham operation as control group. Experimental samples were harvested at 16 h after induction. The protein and mRNA levels of matrix metalloprotease 9 (MMP-9), TM, and EPCR in pancreatic tissue were investigated. Serum tumor necrosis factor alpha (TNF-alpha) and interleukin-8 (IL-8) levels were determined. The severity of disease was evaluated by histological score of pancreatic injury, wet/dry weight ratio of pancreatic tissue, and serum amylase. RESULTS In the APC 50 microg/kg-treated group, serum TNF-alpha, IL-8, and pancreatic MMP-9 levels were decreased and the levels of pancreatic EPCR and TM were up-regulated compared with the SAP group. A significant dose-dependent relationship was found between the decreased levels of serum IL-8 and the APC-treated dosage. Furthermore, the severity of SAP was ameliorated by APC treatment. CONCLUSIONS APC could augment the anti-coagulation and anti-inflammatory activity by up-regulating EPCR and TM expressions, thus attenuating the severity of SAP.
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Affiliation(s)
- Chen Ping
- Department of Gastroenterology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
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Salgado DR, Favory R, Backer DD. Microcirculatory assessment in daily clinical practice - not yet ready but not too far! EINSTEIN-SAO PAULO 2010; 8:107-16. [DOI: 10.1590/s1679-45082010rw1311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Accepted: 12/27/2009] [Indexed: 01/20/2023] Open
Abstract
ABSTRACT Shock is characterized by an alteration in tissue perfusion that may lead to tissue hypoxia. Recent guidelines recommend aggressive and early resuscitation therapy, but mortality rate is still unacceptably high. Unfortunately, traditional clinical surrogates used to guide resuscitation therapy poorly correlate with microcirculatory blood flow, a key determinant of tissue perfusion. New techniques that directly assess microcirculatory perfusion at the bedside have emerged as a complement to traditional macrohemodynamic parameters. These techniques have been supported by several studies showing microcirculatory alterations in different clinical settings. In addition, these microcirculatory alterations are related with outcome and persist regardless of arterial pressure normalization, being a better predictor of organ dysfunction and mortality than global hemodynamic and laboratory parameters. These findings allowed the concept of “microcirculatory-goal directed therapy”, which is now in its preliminary phase, as the impact of many interventions still needs to be assessed. Finally, microcirculation assessment has also been explored in other medical fields such as perioperative, systemic arterial hypertension, heart failure, and hyperviscosity syndromes. In this review, we shortly present the characteristics of microcirculation and the main determinants of capillary blood flow, and we discuss advantages and limitations of some recently available techniques to evaluate microcirculation at the bedside, and how they could be useful for the general clinician in daily practice.
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Affiliation(s)
| | - Raphaël Favory
- Université Libre de Bruxelles, Belgium; Université Lille 2, France
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Behnes M, Brueckmann M, Liebe V, Liebetrau C, Lang S, Putensen C, Borggrefe M, Hoffmann U. Levels of oxidized low-density lipoproteins are increased in patients with severe sepsis. J Crit Care 2009; 23:537-41. [PMID: 19056019 DOI: 10.1016/j.jcrc.2008.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 08/13/2008] [Accepted: 09/15/2008] [Indexed: 11/26/2022]
Abstract
BACKGROUND It was hypothesized that the inflammatory response of patients with severe sepsis may result in changes of plasma levels of oxidized low-density lipoproteins (ox-LDLs) and that drotrecogin alpha (activated) (DAA) (Xigris, Eli Lilly and Company [Indiana 46285, USA]) may influence ox-LDL levels. MATERIALS AND METHODS The ox-LDL levels were measured in severe septic patients on day 1, 4, and 7 of severe sepsis. Patients were treated either with or without DAA. RESULTS The ox-LDL levels increased significantly (P < .05) from day 1 to day 7 (day 1, mean +/- SEM, 25.4 +/- 1.8 U/L; day 4, mean +/- SEM, 34.3 +/- 2.1 U/L; day 7, mean +/- SEM, 38.3 +/- 2.1 U/L) in all patients (n = 68). The ox-LDL levels increased significantly from day 1 to day 7 both in patients treated with (n = 31) and without DAA (n = 37) (P < .001) (DAA-group: day 1, mean +/- SEM, 24.4 +/- 2.8 U/L; day 4, mean +/- SEM, 35.5 +/- 2.9 U/L; day 7, mean +/- SEM, 40.7 +/- 3.2 U/L) (control group: day 1, mean +/- SEM, 26.3 +/- 2.8 U/L; day 4, mean +/- SEM, 33.2 +/- 2.9 U/L; day 7, mean +/- SEM, 36.4 +/- 2.9 U/L). No significant differences of ox-LDL levels were observed between both groups at any point of time (P > .05). CONCLUSIONS The ox-LDL concentrations increase significantly during the first week of severe sepsis and are not affected by administration of drotrecogin alpha (activated) (Xigris).
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Affiliation(s)
- Michael Behnes
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, 68167 Mannheim, Germany
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Tyagi A, Sethi AK, Girotra G, Mohta M. The microcirculation in sepsis. Indian J Anaesth 2009; 53:281-93. [PMID: 20640135 PMCID: PMC2900118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2009] [Indexed: 11/14/2022] Open
Abstract
SUMMARY Sepsis is a leading cause of mortality in critically ill patients. The pathophysiology of sepsis involves a highly complex and integrated response, including the activation of various cell types, inflammatory mediators, and the haemostatic system. Recent evidence suggests an emerging role of the microcirculation in sepsis, necessitating a shift in our locus away Irom the macrohaemodynamics to ill icrohaemodynanmics in a septic patient. This review article provides a brief overview of the microcirculation, its assessment techniques, and specific therapies to resuscitate the microhaemodynamics.
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Affiliation(s)
- Asha Tyagi
- Reader, Department of Anaesthesiology & Critical Care, University College of Medical Sciences & Guru Teg Bahadur Hospital, Shahadra, Delhi-110095, India
| | - Ashok Kumar Sethi
- Professor & Head, Reader, Department of Anaesthesiology & Critical Care, University College of Medical Sciences & Guru Teg Bahadur Hospital, Shahadra, Delhi-110095, India
| | - Gautam Girotra
- Senior Resident, Department of Anaesthesiology & Critical Care, University College of Medical Sciences & Guru Teg Bahadur Hospital, Shahadra, Delhi-110095, India
| | - Medha Mohta
- Reader, Department of Anaesthesiology & Critical Care, University College of Medical Sciences & Guru Teg Bahadur Hospital, Shahadra, Delhi-110095, India
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Recombinant human activated protein C inhibits integrin-mediated neutrophil migration. Blood 2009; 113:4078-85. [PMID: 19244161 DOI: 10.1182/blood-2008-09-180968] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Integrin-mediated cell migration is central to many biologic and pathologic processes. During inflammation, tissue injury results from excessive infiltration and sequestration of activated leukocytes. Recombinant human activated protein C (rhAPC) has been shown to protect patients with severe sepsis, although the mechanism underlying this protective effect remains unclear. Here, we show that rhAPC directly binds to beta(1) and beta(3) integrins and inhibits neutrophil migration, both in vitro and in vivo. We found that human APC possesses an Arg-Gly-Asp (RGD) sequence, which is critical for the inhibition. Mutation of this sequence abolished both integrin binding and inhibition of neutrophil migration. In addition, treatment of septic mice with a RGD peptide recapitulated the beneficial effects of rhAPC on survival. Thus, we conclude that leukocyte integrins are novel cellular receptors for rhAPC and the interaction decreases neutrophil recruitment into tissues, providing a potential mechanism by which rhAPC may protect against sepsis.
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Kuriyama N, Isaji S, Hamada T, Kishiwada M, Ohsawa I, Usui M, Sakurai H, Tabata M, Suzuki K, Uemoto S. Activated protein C prevents hepatic ischaemia-reperfusion injury in rats. Liver Int 2009; 29:299-307. [PMID: 18507760 DOI: 10.1111/j.1478-3231.2008.01796.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Hepatic ischaemia-reperfusion injury (IRI) is a serious complication of liver surgery, especially extended hepatectomy and liver transplantation. Activated protein C (APC), a potent anticoagulant serine protease, has been shown to have cell-protective properties by virtue of its anti-inflammatory and anti-apoptotic activities. METHODS The present study was designed to examine the cytoprotective effects of APC in a 60-min warm-IRI rat model. RESULTS Following a single intravenous injection of APC before reperfusion, APC exerted cytoprotective effects 4 h after reperfusion, as evidenced by: (i) decreased levels of transaminase and improved histological findings of IRI, (ii) reduced infiltration and activation of neutrophils, macrophages and T cells, (iii) reduced expression of tumour necrosis factor-alpha, (iv) reduced expression of P-selectin and intracellular adhesion molecule-1, (v) inhibited coagulation and attenuated sinusoidal endothelial cell injury, (vi) improved hepatic microcirculation and (vii) decreased transferase-mediated dUTP nick end-labelling-positive cells. These effects of APC were observed 4 h but not 24 h after reperfusion. However, multiple injections of APC after reperfusion significantly decreased the levels of transaminase and the activity of myeloperoxidase, and improved histological findings of IRI 24 h after reperfusion. CONCLUSION These results suggest that APC is a promising therapeutic option for hepatic warm-IRI; however, multiple injections of APC are necessary to maintain its cell-protective action over the long term.
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Affiliation(s)
- Naohisa Kuriyama
- Department of Hepatobiliary Pancreatic Surgery, Mie University Graduate School of Medicine, Mie, Japan.
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Fong IW. New Concepts and Emerging Issues in Sepsis. EMERGING ISSUES AND CONTROVERSIES IN INFECTIOUS DISEASE 2009. [PMCID: PMC7122214 DOI: 10.1007/978-0-387-84841-9_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- I. W. Fong
- Professor of Medicine University of Toronto, St. Michael's Hospital, 30 Bond Street, Toronto, ON M5B 1W8 Canada
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Eid A, Wiedermann CJ, Kinasewitz GT. Early Administration of High-Dose Antithrombin in Severe Sepsis: Single Center Results from the KyberSept-Trial. Anesth Analg 2008; 107:1633-8. [DOI: 10.1213/ane.0b013e318184621d] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Trzeciak S, Cinel I, Phillip Dellinger R, Shapiro NI, Arnold RC, Parrillo JE, Hollenberg SM. Resuscitating the microcirculation in sepsis: the central role of nitric oxide, emerging concepts for novel therapies, and challenges for clinical trials. Acad Emerg Med 2008; 15:399-413. [PMID: 18439194 DOI: 10.1111/j.1553-2712.2008.00109.x] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Microcirculatory dysfunction is a critical element of the pathogenesis of severe sepsis and septic shock. In this Bench-to-Bedside review, we present: 1) the central role of the microcirculation in the pathophysiology of sepsis; 2) new translational research techniques of in vivo video microscopy for assessment of microcirculatory flow in human subjects; 3) clinical investigations that reported associations between microcirculatory dysfunction and outcome in septic patients; 4) the potential role of novel agents to "rescue" the microcirculation in sepsis; 5) current challenges facing this emerging field of clinical investigation; and 6) a framework for the design of future clinical trials aimed to determine the impact of novel agents on microcirculatory flow and organ failure in patients with sepsis. We specifically focus this review on the central role and vital importance of the nitric oxide (NO) molecule in maintaining microcirculatory homeostasis and patency, especially when the microcirculation sustains an insult (as with sepsis). We also present the scientific rationale for clinical trials of exogenous NO administration to treat microcirculatory dysfunction and augment microcirculatory blood flow in early sepsis therapy.
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Affiliation(s)
- Stephen Trzeciak
- Department of Emergency Medicine, Division of Critical Care Medicine, University of Medicine and Dentistry of New Jersey (UMDNJ)-Robert Wood Johnson Medical School at Camden, Cooper University Hospital, Camden, NJ, USA.
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Abstract
Severe sepsis is common and increasing in incidence. Mortality rates remain high. Discovery of the link between the coagulation system and the inflammatory response to sepsis led to the development of drotrecogin alpha (activated). This recombinant form of the natural anticoagulant, activated protein C, was shown to reduce 28-day mortality from severe sepsis in a large, randomised, placebo-controlled, multi-centre Phase III study. Although subsequent studies have demonstrated that drotrecogin alpha (activated) is not of benefit to all patients with severe sepsis, it does reduce mortality rates in patients at a high risk of death. Drotrecogin alpha (activated) is associated with an increased risk of bleeding. Recent studies have shed light on its mode of action, which is primarily attributed today to cytoprotective effects especially on the endothelium with improved microcirculation. Ongoing studies will help define which patients are most likely to benefit, perhaps with the help of biochemical markers.
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Affiliation(s)
- Jean-Louis Vincent
- Free University of Brussels, Erasme University Hospital, Department of Intensive Care, Route de Lennik, 808, B-1070 Brussels, Belgium.
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Wang Z, Su F, Rogiers P, Vincent JL. Beneficial effects of recombinant human activated protein C in a ewe model of septic shock*. Crit Care Med 2007; 35:2594-600. [PMID: 17901839 DOI: 10.1097/01.ccm.0000287590.55294.40] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To investigate the effects of activated protein C (APC) in a clinically relevant animal model of septic shock. DESIGN Prospective, randomized, controlled study. SETTING University medical center research laboratory. SUBJECTS Eighteen female sheep (body weight, 27-35 kg). INTERVENTIONS Animals were fasted, anesthetized, invasively monitored, and mechanically ventilated before receiving 0.5 g/kg body weight of feces intraperitoneally to induce sepsis. Fluid resuscitation with Ringer lactate was titrated to maintain pulmonary artery occlusion pressure at baseline levels. No vasoactive agents or antibiotics were used. Two hours after the induction of sepsis, animals were randomized to receive an infusion of APC (24 microg x kg(-1) x hr(-1), n = 9) or an equivalent volume of vehicle (n = 9) throughout the experimental period. MEASUREMENTS AND MAIN RESULTS The APC-treated animals had significantly higher arterial pressure, urine output, PaO2/FIO2 ratios, and thoracopulmonary compliance than the control animals. They had lower pulmonary arterial pressure and arterial lactate concentrations than the control animals. Plasma colloid oncotic pressure was better maintained in the APC-treated group than in the control group (p < .05). Prothrombin time and activated partial thromboplastin time were altered less, and plasma D-dimer concentrations were significantly lower in the APC-treated group than in the control group (p < .05). The blood protein C concentration and platelet count were maintained better in the APC-treated group than in the control group (p < .05). APC administration was associated with significantly longer survival (median, 27 hrs vs. 20 hrs; p < .05). At postmortem examination, the lung wet/dry ratio was significantly lower in the APC group than in the control group (6.3 +/- 0.7 vs. 7.1 +/- 1.2, p < .05). CONCLUSIONS In this clinically relevant model of septic shock due to fecal peritonitis, administration of APC had beneficial effects on hemodynamic variables, gas exchange, lactic acidosis, and coagulation abnormalities. Higher colloid oncotic pressures and lower lung wet/dry ratios at autopsy suggest preserved endothelial integrity. APC administration resulted in prolonged survival.
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Affiliation(s)
- Zhen Wang
- Department of Intensive Care, Erasme Hospital, Free University of Brussels, Belgium
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Wang J, Boerma M, Fu Q, Hauer-Jensen M. Significance of endothelial dysfunction in the pathogenesis of early and delayed radiation enteropathy. World J Gastroenterol 2007; 13:3047-55. [PMID: 17589919 PMCID: PMC4172610 DOI: 10.3748/wjg.v13.i22.3047] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 02/03/2007] [Accepted: 02/25/2007] [Indexed: 02/06/2023] Open
Abstract
This review summarizes the current state of knowledge regarding the role of endothelial dysfunction in the pathogenesis of early and delayed intestinal radiation toxicity and discusses various endothelial-oriented interventions aimed at reducing the risk of radiation enteropathy. Studies published in the biomedical literature during the past four decades and cited in PubMed, as well as clinical and laboratory data from our own research program are reviewed. The risk of injury to normal tissues limits the cancer cure rates that can be achieved with radiation therapy. During treatment of abdominal and pelvic tumors, the intestine is frequently a major dose-limiting factor. Microvascular injury is a prominent feature of both early (inflammatory), as well as delayed (fibroproliferative) radiation injuries in the intestine and in many other normal tissues. Evidence from our and other laboratories suggests that endothelial dysfunction, notably a deficiency of endothelial thrombomodulin, plays a key role in the pathogenesis of these radiation responses. Deficient levels of thrombomodulin cause loss of vascular thromboresistance, excessive activation of cellular thrombin receptors by thrombin, and insufficient activation of protein C, a plasma protein with anticoagulant, anti-inflammatory, and cytoprotective properties. These changes are presumed to be critically involved in many aspects of early intestinal radiation toxicity and may sustain the fibroproliferative processes that lead to delayed intestinal dysfunction, fibrosis, and clinical complications. In conclusion, injury of vascular endothelium is important in the pathogenesis of the intestinal radiation response. Endothelial-oriented interventions are appealing strategies to prevent or treat normal tissue toxicity associated with radiation treatment of cancer.
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Affiliation(s)
- Junru Wang
- Department of Surgery, University of Arkansas for Medical Sciences, United States
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Hoffmann JN, Schick K. Antithrombin and hypercoagulability in sepsis: insights from thrombelastography? Crit Care 2007; 11:115. [PMID: 17331267 PMCID: PMC2151912 DOI: 10.1186/cc5156] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Antithrombin (AT) has been used for over 25 years to successfully treat disseminated intravascular coagulation (DIC). A four-day AT therapy in patients with DIC in the KyberSept trial has been related to a clear survival benefit in patients not receiving concomitant heparin. Gonano and coworkers performed thrombelastography (TEG) measurements in patients with severe sepsis and clearly showed hypercoagulability, as defined by five TEG parameters, compared to healthy controls. In the AT group they found a trend towards normalization of TEG parameters after treatment, although this did not reach statistical significance. This first clinical evaluation of hypercoagulability during AT treatment could not provide evidence for an attenuation of coagulopathy, an effect that might be due to high inter-individual variability.
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Brueckmann M, Hoffmann U, Engelhardt C, Lang S, Fukudome K, Haase KK, Liebe V, Kaden JJ, Putensen C, Borggrefe M, Huhle G. Prognostic value of platelet-derived growth factor in patients with severe sepsis. Growth Factors 2007; 25:15-24. [PMID: 17454146 DOI: 10.1080/08977190701272784] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
PRIMARY OBJECTIVE Platelet-derived growth factor-BB (PDGF-BB) has been shown to promote the structural integrity of the vessel wall and to increase wound healing capacity. Aim of the present study was to determine the role of PDGF-BB in the context of outcome of septic patients. Furthermore, the effect of treatment with recombinant human activated protein C (rhAPC) on plasma levels of PDGF-BB in severe sepsis was evaluated as well as the in vitro effect of rhAPC on PDGF-BB-release from human endothelial cells (HUVEC). RESEARCH DESIGN, METHODS AND PROCEDURES: PDGF-BB levels were measured in 46 patients on day 3 of severe sepsis. Twenty-one of these patients received treatment with rhAPC. The in vitro effect of rhAPC on PDGF-BB-messenger RNA synthesis and release of PDGF-BB into supernatants was measured by reverse transcriptase-polymerase chain reaction and ELISA-methods. MAIN OUTCOMES AND RESULTS Survivors of severe sepsis presented with higher PDGF-BB levels than non-survivors (p < 0.05). Septic patients with PDGF-BB levels below 200 pg/ml were 7.3 times more likely (RR = 7.3, 95% CI: 1.4-44.5; p < 0.05) to die from sepsis than patients with higher PDGF-BB values. RhAPC (1-10 microg/ml) stimulated endothelial PDGF-BB-messenger RNA transcription and PDGF-BB-release in vitro. Plasma levels of PDGF-BB in patients receiving rhAPC were significantly (p < 0.01) higher (median 277.7; 25-75th percentiles: 150.5-414.4 pg/ml) than in patients not treated with rhAPC (median: 125.6; 25-75th percentiles: 55.3-344.7 pg/ml). CONCLUSIONS The ability of rhAPC to upregulate endothelial PDGF-BB production may represent a new molecular mechanism by which rhAPC controls vessel wall homeostasis and increases tissue healing capacity in severe sepsis. PDGF-BB may serve as useful laboratory marker to predict survival in patients presenting with severe sepsis.
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Affiliation(s)
- Martina Brueckmann
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg. Mannheim, Germany.
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Abstract
Severe sepsis is a common and frequently fatal condition. Evidence showing a link between the coagulation system and the inflammatory response to sepsis led to the development of drotrecogin alfa (activated) as an agent in the treatment of severe sepsis. Recent studies have shown that the mode of action is actually more complex than initially thought. This recombinant form of the natural anticoagulant, activated protein C, has been demonstrated to reduce mortality in a large randomized controlled, Phase III study involving 1690 patients, even though the results of this and subsequent studies and the licensing of drotrecogin alfa (activated) have generated considerable debate. Administration of drotrecogin alfa (activated) is associated with an increased risk of bleeding and its use is contraindicated in patients with a high risk of bleeding or recent hemorrhagic events.
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Affiliation(s)
- Jean-Louis Vincent
- Erasme University Hospital, Department of Intensive Care, Route de Lennik, 808, B-1070 Brussels, Belgium.
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Abstract
The endothelium is a viable target for injury, repair and cellular modulation. Because of its vast extension and active metabolic status of producing mediators for vasomotor tone, coagulation, and inflammation, it is a key target for therapy during ischemia/reperfusion injury. Cardiopulmonary resuscitation is a model of whole-body ischemia/reperfusion injury. It has become apparent that the endothelium participates in a host of responses elicited by ischemia/reperfusion. This review examines the role of the endothelium during and after ischemia/reperfusion and the participation by its mediators and evidence for endothelial involvement during and after cardiopulmonary resuscitation. The strategic location of the endothelium makes it an excellent signal transduction mechanism for a host of disease processes. In addition to biochemical stimuli, mechanical stimulation of the endothelium elicits production of several mediators, including endothelium-derived nitric oxide, prostaglandins, and antithrombotics and anticoagulants. Whole-body, periodic acceleration is a novel method of stimulating the endothelium via pulsatile shear stress. Periodic acceleration has been shown to be an effective experimental method of cardiopulmonary resuscitation, with evidence of postresuscitation cardioprotective effects. This review indicates that understanding endothelial modulation during and after ischemia/reperfusion will significantly improve therapeutic choices.
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Affiliation(s)
- Jose A Adams
- Department of Neonatology, Mount Sinai Medical Center, Miami Beach, Florida, USA
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Abstract
Severe sepsis is a major cause of morbidity and mortality in the critically ill patient. Management involves identification and treatment of the underlying causative infection, with antimicrobial agents and surgery where necessary, haemodynamic resuscitation with fluids and vasoactive agents, steroids (for septic shock) and immunomodulation with drotrecogin-alpha (activated), where not contraindicated. Every effort must be made to identify sepsis early so as to optimise the patient's chances of a good outcome.
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Affiliation(s)
- Jean-Louis Vincent
- Department of Intensive Care, Erasme University Hospital, Route de Lennik 808, B-1070 Brussels, Belgium.
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Hoffmann JN, Fertmann JM, Jauch KW. Microcirculatory disorders in sepsis and transplantation: therapy with natural coagulatory inhibitors antithrombin and activated protein C. Curr Opin Crit Care 2006; 12:426-30. [PMID: 16943720 DOI: 10.1097/01.ccx.0000244121.54495.f7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Modern technologies allow visualization of microcirculatory disorders. This review describes how the coagulatory inhibitors antithrombin and activated protein C (APC) can improve microcirculation in sepsis and transplantation. RECENT FINDINGS The effects of antithrombin and APC on microcirculatory disorders in ischemia reperfusion and experimental sepsis have been reported recently. In addition, antithrombin has recently been clinically used to reduce graft pancreatitis after pancreas-kidney transplantation, and to improve kidney perfusion. It was demonstrated that septic capillary perfusion failure as well as leukocyte-endothelial cell interactions can be reversed by high-dose prophylactic antithrombin application. APC was also highly effective in this context. Thus, APC could improve microcirculatory blood flow in septic patients as recently measured by in-vivo orthogonal polarization spectral imaging techniques. For antithrombin, comparable measurements in humans are currently not available. SUMMARY Microcirculatory dysfunction plays a key role in the development of organ dysfunction in septic patients and after solid organ transplantation. The exogenous application of coagulatory inhibitors may provide a new important strategy for prevention and treatment of microcirculatory disorders. This mode of action may be the reason why coagulatory inhibitors could improve mortality in septic patients without directly influencing inflammatory mediator concentrations.
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Abstract
Microcirculatory dysfunctions play a central role in the pathophysiology of sepsis and shock. Modern methods enable microvascular monitoring in man and offer the possibility to test the effect of novel therapeutical strategies for sepsis. Furthermore, these techniques may be future tools for the monitoring of critically ill patients. In this review, we will describe four microvascular monitoring devices and give an overview of the microcirculatory changes observed during the course of sepsis. Laser Doppler fluxmetry is an easy to use noninvasive technique to measure tissue perfusion enabling monitoring of the effect of different catecholamines on the gastric perfusion during sepsis. Increased microvascular permeability and altered blood flow in septic patients can be quantified by venous congestion plethysmography. Alterations in sublingual microvascular blood flow are detected by intravital microscopy in septic patients and were identified as an outcome predictor. Furthermore, the role of gastrointestinal pCO2-tonometry for microcirculatory monitoring of the perfusion of splanchnic organs during sepsis is discussed. The true clinical value of these techniques has yet to be established and will depend on larger clinical trials showing an impact on diagnostics and patient management.
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Affiliation(s)
- A Bauer
- Klinik für Anaesthesiologie, Klinikum der Universität München-Grosshadern, Marchioninistrasse 15, 81377 München-Grosshadern
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