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Negrini D. Morphological, Mechanical and Hydrodynamic Aspects of Diaphragmatic Lymphatics. Biology (Basel) 2022; 11:biology11121803. [PMID: 36552311 PMCID: PMC9775868 DOI: 10.3390/biology11121803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/05/2022] [Accepted: 12/08/2022] [Indexed: 12/15/2022]
Abstract
The diaphragmatic lymphatic vascular network has unique anatomical characteristics. Studying the morphology and distribution of the lymphatic network in the mouse diaphragm by fluorescence-immunohistochemistry using LYVE-1 (a lymphatic endothelial marker) revealed LYVE1+ structures on both sides of the diaphragm-both in its the muscular and tendinous portion, but with different vessel density and configurations. On the pleural side, most LYVE1+ configurations are vessel-like with scanty stomata, while the peritoneal side is characterized by abundant LYVE1+ flattened lacy-ladder shaped structures with several stomata-like pores, particularly in the muscular portion. Such a complex, three-dimensional organization is enriched, at the peripheral rim of the muscular diaphragm, with spontaneously contracting lymphatic vessel segments able to prompt contractile waves to adjacent collecting lymphatics. This review aims at describing how the external tissue forces developing in the diaphragm, along with cyclic cardiogenic and respiratory swings, interplay with the spontaneous contraction of lymphatic vessel segments at the peripheral diaphragmatic rim to simultaneously set and modulate lymph flow from the pleural and peritoneal cavities. These details may provide useful in understanding the role of diaphragmatic lymphatics not only in physiological but, more so, in pathophysiological circumstances such as in dialysis, metastasis or infection.
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Affiliation(s)
- Daniela Negrini
- Department of Medicine and Surgery, University of Insubria, 21100 Varese, Italy
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2
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Yu L, Noor MS, Kiss ZHT, Murari K. Monitoring stimulus-evoked hemodynamic response during deep brain stimulation with single fiber spectroscopy. J Biophotonics 2022; 15:e202200076. [PMID: 36054592 DOI: 10.1002/jbio.202200076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 06/30/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Deep brain stimulation (DBS) is a revolutionary treatment for movement disorders. Measuring DBS-induced hemodynamic responses may be useful for surgical guidance of DBS electrode implantation as well as to study the mechanism and assess therapeutic effects of DBS. In this study, we evaluated the performance of a single fiber spectroscopic (SFS) system for measuring hemodynamic response in different cortical layers in a DBS animal model. We showed that SFS is capable of measuring minute relative changes in oxygen saturation and blood volume fraction in-vivo at a sampling rate of 22-33 Hz. During stimulation, blood volume fraction increased, while oxygen saturation showed both increases and decreases at different cortical depths across animals. In addition, we showed the potential of using SFS for measuring other physiological parameters, for example, heart rate, and respiratory rate.
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Affiliation(s)
- Linhui Yu
- Electrical and Software Engineering, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - M Sohail Noor
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Biomedical Engineering, University of Calgary, Calgary, Alberta, Canada
| | - Zelma H T Kiss
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Kartikeya Murari
- Electrical and Software Engineering, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Biomedical Engineering, University of Calgary, Calgary, Alberta, Canada
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3
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Nyberg A, Gremo E, Blixt J, Sperber J, Larsson A, Lipcsey M, Pikwer A, Castegren M. Lung-protective ventilation increases cerebral metabolism and non-inflammatory brain injury in porcine experimental sepsis. BMC Neurosci 2021; 22:31. [PMID: 33926378 PMCID: PMC8082058 DOI: 10.1186/s12868-021-00629-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 03/23/2021] [Indexed: 12/03/2022] Open
Abstract
Background Protective ventilation with lower tidal volumes reduces systemic and organ-specific inflammation. In sepsis-induced encephalopathy or acute brain injury the use of protective ventilation has not been widely investigated (experimentally or clinically). We hypothesized that protective ventilation would attenuate cerebral inflammation in a porcine endotoxemic sepsis model. The aim of the study was to study the effect of tidal volume on cerebral inflammatory response, cerebral metabolism and brain injury. Nine animals received protective mechanical ventilation with a tidal volume of 6 mL × kg−1 and nine animals were ventilated with a tidal volume of 10 mL × kg−1. During a 6-h experiment, the pigs received an endotoxin intravenous infusion of 0.25 µg × kg−1 × h−1. Systemic, superior sagittal sinus and jugular vein blood samples were analysed for inflammatory cytokines and S100B. Intracranial pressure, brain tissue oxygenation and brain microdialysis were sampled every hour. Results No differences in systemic or sagittal sinus levels of TNF-α or IL-6 were seen between the groups. The low tidal volume group had increased cerebral blood flow (p < 0.001) and cerebral oxygen delivery (p < 0.001), lower cerebral vascular resistance (p < 0.05), higher cerebral metabolic rate (p < 0.05) along with higher cerebral glucose consumption (p < 0.05) and lactate production (p < 0.05). Moreover, low tidal volume ventilation increased the levels of glutamate (p < 0.01), glycerol (p < 0.05) and showed a trend towards higher lactate to pyruvate ratio (p = 0.08) in cerebral microdialysate as well as higher levels of S-100B (p < 0.05) in jugular venous plasma compared with medium–high tidal volume ventilation. Conclusions Contrary to the hypothesis, protective ventilation did not affect inflammatory cytokines. The low tidal volume group had increased cerebral blood flow, cerebral oxygen delivery and cerebral metabolism together with increased levels of markers of brain injury compared with medium–high tidal volume ventilation. Supplementary Information The online version contains supplementary material available at 10.1186/s12868-021-00629-0.
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Affiliation(s)
- Axel Nyberg
- Centre for Clinical Research Sörmland, Uppsala University, Uppsala, Sweden.,Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Erik Gremo
- Centre for Clinical Research Sörmland, Uppsala University, Uppsala, Sweden
| | - Jonas Blixt
- Perioperative Medicine and Intensive Care (PMI), Karolinska University Hospital, Stockholm, Sweden.,The Department of Physiology and Pharmacology (FyFa), Karolinska Institute, Stockholm, Sweden
| | - Jesper Sperber
- Centre for Clinical Research Sörmland, Uppsala University, Uppsala, Sweden.,Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Anders Larsson
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Miklós Lipcsey
- Hedenstierna Laboratory, CIRRUS, Anesthesiology and Intensive Care, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Andreas Pikwer
- Centre for Clinical Research Sörmland, Uppsala University, Uppsala, Sweden.,Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Markus Castegren
- Centre for Clinical Research Sörmland, Uppsala University, Uppsala, Sweden. .,Department of Medical Sciences, Uppsala University, Uppsala, Sweden. .,Perioperative Medicine and Intensive Care (PMI), Karolinska University Hospital, Stockholm, Sweden. .,The Department of Physiology and Pharmacology (FyFa), Karolinska Institute, Stockholm, Sweden. .,Department of Anaesthesiology & Intensive Care, Centre for Clinical Research, Sörmland, Mälarsjukhuset, 631 88, Eskilstuna, Sweden.
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Nguyen TK, Mai DH, Le AN, Nguyen QH, Nguyen CT, Vu TA. A review of intraoperative lung-protective mechanical ventilation strategy. Trends in Anaesthesia and Critical Care 2021. [DOI: 10.1016/j.tacc.2020.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Cruces P, Erranz B, Lillo F, Sarabia-Vallejos MA, Iturrieta P, Morales F, Blaha K, Medina T, Diaz F, Hurtado DE. Mapping regional strain in anesthetised healthy subjects during spontaneous ventilation. BMJ Open Respir Res 2019; 6:e000423. [PMID: 31749967 PMCID: PMC6830454 DOI: 10.1136/bmjresp-2019-000423] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 09/17/2019] [Accepted: 10/09/2019] [Indexed: 01/03/2023] Open
Abstract
Introduction Breathing produces a phenomenon of cyclic deformation throughout life. Biomechanically, deformation of the lung is measured as strain. Regional strain recently started to be recognised as a tool in the study of lung pathophysiology, but regional lung strain has not been studied in healthy subjects breathing spontaneously without voluntary or pharmacological control of ventilation. Our aim is to generate three-dimensional (3D) regional strain and heterogeneity maps of healthy rat lungs and describe their changes over time. Methods Micro-CT and image-based biomechanical analysis by finite element approach were carried out in six anaesthetised rats under spontaneous breathing in two different states, at the beginning of the experiment and after 3 hours of observation. 3D regional strain maps were constructed and divided into 10 isovolumetric region-of-interest (ROI) in three directions (apex to base, dorsal to ventral and costal to mediastinal), allowing to regionally analyse the volumetric strain, the strain progression and the strain heterogeneity. To describe in depth these parameters, and systematise their report, we defined regional strain heterogeneity index [1+strain SD ROI(x)]/[1+strain mean ROI(x)] and regional strain progression index [ROI(x)-mean of final strain/ROI(x)-mean of initial strain]. Results We were able to generate 3D regional strain maps of the lung in subjects without respiratory support, showing significant differences among the three analysed axes. We observed a significantly lower regional volumetric strain in the apex sector compared with the base, with no significant anatomical systematic differences in the other directions. This heterogeneity could not be identified with physiological or standard CT methods. There was no progression of the analysed regional volumetric strain when the two time-points were compared. Discussion It is possible to map the regional volumetric strain in the lung for healthy subjects during spontaneous breathing. Regional strain heterogeneity and changes over time can be measured using a CT image-based numerical analysis applying a finite element approach. These results support that healthy lung might have significant regional strain and its spatial distribution is highly heterogeneous. This protocol for CT image acquisition and analysis could be a useful tool for helping to understand the mechanobiology of the lung in many diseases.
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Affiliation(s)
- Pablo Cruces
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile.,Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Benjamin Erranz
- Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Felipe Lillo
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | | | - Pablo Iturrieta
- Pediatric Intensive Care Unit, Hospital Padre Hurtado, Santiago, Chile
| | - Felipe Morales
- Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - Katherine Blaha
- Pediatric Intensive Care Unit, Hospital Clínico La Florida Dra. Eloisa Diaz Insunza, Santiago, Chile
| | - Tania Medina
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile
| | - Franco Diaz
- Pediatric Intensive Care Unit, Hospital El Carmen de Maipú, Santiago, Chile.,Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Millennium Nucleus for Cardiovascular Magnetic Resonance, Santiago, Chile
| | - Daniel E Hurtado
- Pediatric Intensive Care Unit, Hospital Padre Hurtado, Santiago, Chile.,Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Structural and Geotechnical Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
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Cruz FF, Rocco PRM, Pelosi P. Role of the extracellular matrix in the genesis of ventilator-induced lung injury. Med Klin Intensivmed Notfmed 2018; 113:2-6. [DOI: 10.1007/s00063-017-0376-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 10/14/2017] [Indexed: 01/20/2023]
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7
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Severgnini P, Bacuzzi A, Guzzetti L, Selmo G, Peluso L, Chiaranda M. Protective Ventilation in general anesthesia. Anything new? ACTA ACUST UNITED AC 2018; 65:218-24. [PMID: 29102404 DOI: 10.1016/j.redar.2017.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 08/23/2017] [Indexed: 11/23/2022]
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8
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Güldner A, Kiss T, Serpa Neto A, Hemmes SN, Canet J, Spieth PM, Rocco PR, Schultz MJ, Pelosi P, Gama de Abreu M. Intraoperative protective mechanical ventilation for prevention of postoperative pulmonary complications: a comprehensive review of the role of tidal volume, positive end-expiratory pressure, and lung recruitment maneuvers. Anesthesiology 2015; 123:692-713. [PMID: 26120769 DOI: 10.1097/ALN.0000000000000754] [Citation(s) in RCA: 232] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Postoperative pulmonary complications are associated with increased morbidity, length of hospital stay, and mortality after major surgery. Intraoperative lung-protective mechanical ventilation has the potential to reduce the incidence of postoperative pulmonary complications. This review discusses the relevant literature on definition and methods to predict the occurrence of postoperative pulmonary complication, the pathophysiology of ventilator-induced lung injury with emphasis on the noninjured lung, and protective ventilation strategies, including the respective roles of tidal volumes, positive end-expiratory pressure, and recruitment maneuvers. The authors propose an algorithm for protective intraoperative mechanical ventilation based on evidence from recent randomized controlled trials.
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Callahan LM, Ross SM, Jones ML, Musk GC. Mortality associated with using medetomidine and ketamine for general anesthesia in pregnant and nonpregnant Wistar rats. Lab Anim (NY) 2014; 43:208-14. [PMID: 24845007 DOI: 10.1038/laban.517] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 03/07/2014] [Indexed: 11/08/2022]
Abstract
Medetomidine and ketamine are injectable drugs that can be used in combination to induce general anesthesia in rats. After noticing a high incidence of morbidity and mortality in pregnant Wistar rats given medetomidine and ketamine for anesthesia, the authors further investigated the effects of this combination of anesthetic drugs in both pregnant and nonpregnant Wistar rats. The time to recumbency and the duration of general anesthesia were similar between pregnant and nonpregnant rats. Pregnancy status did not affect the rats' pulse rate, respiratory rate, rectal temperature, oxygen saturation or perfusion index during 2 h of anesthesia. Pregnant rats had significantly lower blood glucose concentrations than nonpregnant rats at all time points, though blood glucose concentrations increased in both groups. The mortality rate was ∼15% both for nonpregnant rats and for pregnant rats. Researchers using medetomidine and ketamine to anesthetize Wistar rats should carefully monitor the rats in order to minimize mortality.
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Carvalho NC, Güldner A, Beda A, Rentzsch I, Uhlig C, Dittrich S, Spieth PM, Wiedemann B, Kasper M, Koch T, Richter T, Rocco PR, Pelosi P, de Abreu MG. Higher levels of spontaneous breathing reduce lung injury in experimental moderate acute respiratory distress syndrome. Crit Care Med 2014; 42:e702-15. [PMID: 25162475 DOI: 10.1097/CCM.0000000000000605] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To assess the effects of different levels of spontaneous breathing during biphasic positive airway pressure/airway pressure release ventilation on lung function and injury in an experimental model of moderate acute respiratory distress syndrome. DESIGN Multiple-arm randomized experimental study. SETTING University hospital research facility. SUBJECTS Thirty-six juvenile pigs. INTERVENTIONS Pigs were anesthetized, intubated, and mechanically ventilated. Moderate acute respiratory distress syndrome was induced by repetitive saline lung lavage. Biphasic positive airway pressure/airway pressure release ventilation was conducted using the airway pressure release ventilation mode with an inspiratory/expiratory ratio of 1:1. Animals were randomly assigned to one of four levels of spontaneous breath in total minute ventilation (n = 9 per group, 6 hr each): 1) biphasic positive airway pressure/airway pressure release ventilation, 0%; 2) biphasic positive airway pressure/airway pressure release ventilation, > 0-30%; 3) biphasic positive airway pressure/airway pressure release ventilation, > 30-60%, and 4) biphasic positive airway pressure/airway pressure release ventilation, > 60%. MEASUREMENTS AND MAIN RESULTS The inspiratory effort measured by the esophageal pressure time product increased proportionally to the amount of spontaneous breath and was accompanied by improvements in oxygenation and respiratory system elastance. Compared with biphasic positive airway pressure/airway pressure release ventilation of 0%, biphasic positive airway pressure/airway pressure release ventilation more than 60% resulted in lowest venous admixture, as well as peak and mean airway and transpulmonary pressures, redistributed ventilation to dependent lung regions, reduced the cumulative diffuse alveolar damage score across lungs (median [interquartile range], 11 [3-40] vs 18 [2-69]; p < 0.05), and decreased the level of tumor necrosis factor-α in ventral lung tissue (median [interquartile range], 17.7 pg/mg [8.4-19.8] vs 34.5 pg/mg [29.9-42.7]; p < 0.05). Biphasic positive airway pressure/airway pressure release ventilation more than 0-30% and more than 30-60% showed a less consistent pattern of improvement in lung function, inflammation, and damage compared with biphasic positive airway pressure/airway pressure release ventilation more than 60%. CONCLUSIONS In this model of moderate acute respiratory distress syndrome in pigs, biphasic positive airway pressure/airway pressure release ventilation with levels of spontaneous breath higher than usually seen in clinical practice, that is, more than 30% of total minute ventilation, reduced lung injury with improved respiratory function, as compared with protective controlled mechanical ventilation.
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Sperber J, Lipcsey M, Larsson A, Larsson A, Sjölin J, Castegren M. Lung protective ventilation induces immunotolerance and nitric oxide metabolites in porcine experimental postoperative sepsis. PLoS One 2013; 8:e83182. [PMID: 24349457 PMCID: PMC3861481 DOI: 10.1371/journal.pone.0083182] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 10/22/2013] [Indexed: 01/16/2023] Open
Abstract
Low tidal volume ventilation is beneficial in patients with severe pulmonary dysfunction and would, in theory, reduce postoperative complications if implemented during routine surgery. The study aimed to investigate whether low tidal volume ventilation and high positive end-expiratory pressure (PEEP) in a large animal model of postoperative sepsis would attenuate the systemic inflammatory response and organ dysfunction. Thirty healthy pigs were randomized to three groups: Group Prot-7h, i.e. protective ventilation for 7 h, was ventilated with a tidal volume of 6 mL x kg-1 for 7 h; group Prot-5h, i.e. protective ventilation for 5 h, was ventilated with a tidal volume of 10 mL x kg-1 for 2 h, after which the group was ventilated with a tidal volume of 6 mL x kg-1; and a control group that was ventilated with a tidal volume of 10 mL x kg-1 for 7 h. In groups Prot-7h and Prot-5h PEEP was 5 cmH2O for 2 h and 10 cmH2O for 5 h. In the control group PEEP was 5 cmH2O for the entire experiment. After surgery for 2 h, postoperative sepsis was simulated with an endotoxin infusion for 5 h. Low tidal volume ventilation combined with higher PEEP led to lower levels of interleukin 6 and 10 in plasma, higher PaO2/FiO2, better preserved functional residual capacity and lower plasma troponin I as compared with animals ventilated with a medium high tidal volume and lower PEEP. The beneficial effects of protective ventilation were seen despite greater reductions in cardiac index and oxygen delivery index. In the immediate postoperative phase low VT ventilation with higher PEEP was associated with reduced ex vivo plasma capacity to produce TNF-α upon endotoxin stimulation and higher nitrite levels in urine. These findings might represent mechanistic explanations for the attenuation of systemic inflammation and inflammatory-induced organ dysfunction.
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Affiliation(s)
- Jesper Sperber
- Centre for Clinical Research Sörmland, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Infectious Diseases, Uppsala University, Uppsala, Sweden
- * E-mail:
| | - Miklós Lipcsey
- Department of Surgical Sciences, Anaesthesiology and Intensive Care, Uppsala University, Uppsala, Sweden
| | - Anders Larsson
- Department of Surgical Sciences, Anaesthesiology and Intensive Care, Uppsala University, Uppsala, Sweden
| | - Anders Larsson
- Department of Medical Sciences, Biochemical Structure and Function, Uppsala University, Uppsala, Sweden
| | - Jan Sjölin
- Department of Medical Sciences, Infectious Diseases, Uppsala University, Uppsala, Sweden
| | - Markus Castegren
- Centre for Clinical Research Sörmland, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Infectious Diseases, Uppsala University, Uppsala, Sweden
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Abstract
The pleural space plays an important role in respiratory function as the negative intrapleural pressure regimen ensures lung expansion and in the mean time maintains the tight mechanical coupling between the lung and the chest wall. The efficiency of the lung-chest wall coupling depends upon pleural liquid volume, which in turn reflects the balance between the filtration of fluid into and its egress out of the cavity. While filtration occurs through a single mechanism passively driving fluid from the interstitium of the parietal pleura into the cavity, several mechanisms may co-operate to remove pleural fluid. Among these, the pleural lymphatic system emerges as the most important one in quantitative terms and the only one able to cope with variable pleural fluid volume and drainage requirements. In this review, we present a detailed account of the actual knowledge on: (a) the complex morphology of the pleural lymphatic system, (b) the mechanism supporting pleural lymph formation and propulsion, (c) the dependence of pleural lymphatic function upon local tissue mechanics and (d) the effect of lymphatic inefficiency in the development of clinically severe pleural and, more in general, respiratory pathologies.
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Affiliation(s)
- D. Negrini
- Department of Surgical and Morphological Sciences; University of Insubria; Varese; Italy
| | - A. Moriondo
- Department of Surgical and Morphological Sciences; University of Insubria; Varese; Italy
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Affiliation(s)
- M. Fähling
- Institute of Vegetative Physiology; Charité-Universitaetsmedizin Berlin; Berlin; Germany
| | - P. B. Persson
- Institute of Vegetative Physiology; Charité-Universitaetsmedizin Berlin; Berlin; Germany
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Abstract
Brain or lung injury or both are frequent causes of admission to intensive care units and are associated with high morbidity and mortality rates. Mechanical ventilation, which is commonly used in the management of these critically ill patients, can induce an inflammatory response, which may be involved in distal organ failure. Thus, there may be a complex crosstalk between the lungs and other organs, including the brain. Interestingly, survivors from acute lung injury/acute respiratory distress syndrome frequently have some cognitive deterioration at hospital discharge. Such neurologic dysfunction might be a secondary marker of injury and the neuroanatomical substrate for downstream impairment of other organs. Brainlung interactions have received little attention in the literature, but recent evidence suggests that both the lungs and brain can promote inflammation through common mediators. The present commentary discusses the main physiological issues related to brain-lung interactions.
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Affiliation(s)
- Paolo Pelosi
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Largo Rosanna Benzi 8, 16132, Genoa, Italy.
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