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71.
Kristian?SolteszEmail authorView authors OrcID profile Trygve?Sj?berg Tomas?Jansson Rolf?Johansson Anders?Robertsson Audrius?Paskevicius Quiming?Liao Guangqi?Qin Stig?Steen 《Journal of clinical monitoring and computing》2018,32(3):429-437
The purpose of this concept study was to investigate the possibility of automatic mean arterial pressure (MAP) regulation in a porcine heart-beating brain death (BD) model. Hemodynamic stability of BD donors is necessary for maintaining acceptable quality of donated organs for transplantation. Manual stabilization is challenging, due to the lack of vasomotor function in BD donors. Closed-loop stabilization therefore has the potential of increasing availability of acceptable donor organs, and serves to indicate feasibility within less demanding patient groups. A dynamic model of nitroglycerine pharmacology, suitable for controller synthesis, was identified from an experiment involving an anesthetized pig, using a gradient-based output error method. The model was used to synthesize a robust PID controller for hypertension prevention, evaluated in a second experiment, on a second, brain dead, pig. Hypotension was simultaneously prevented using closed-loop controlled infusion of noradrenaline, by means of a previously published controller. A linear model of low order, with variable (uncertain) gain, was sufficient to describe the dynamics to be controlled. The robustly tuned PID controller utilized in the second experiment kept the MAP within a user-defined range. The system was able to prevent hypertension, exceeding a reference of 100 mmHg by more than 10%, during 98% of a 12 h experiment. This early work demonstrates feasibility of the investigated modelling and control synthesis approach, for the purpose of maintaining normotension in a porcine BD model. There remains a need to characterize individual variability, in order to ensure robust performance over the expected population. 相似文献
72.
Otavio Rizzi Coelho-Filho Ravi Shah Carlos Fernando Ramos Lavagnoli Jose Carlos Barros Tomas G. Neilan Venkatesh L. Murthy Pedro Paulo Martins de Oliveira Jose Roberto Matos Souza Elaine Soraya Barbosa de Oliveira Severino Karlos Alexandre de Souza Vilarinho Lindemberg da Mota Silveira Filho Jose Garcia Marc J. Semigran Otavio Rizzi Coelho Michael Jerosch-Herold Orlando Petrucci 《The international journal of cardiovascular imaging》2018,34(1):15-24
After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47?±?7 years, 30?% female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5?±?15 years; LVEF 63.5?±?7?%). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3?±?11?%) with higher LV mass relative to age-matched healthy volunteers (114?±?27 vs. 85.8?±?18 g; p?<?0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τic), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39?±?0.06 vs. 0.28?±?0.03, p?<?0.0001; τic: 0.12?±?0.08 vs. 0.08?±?0.03, p?<?0.001). ECV was associated with LV mass (r?=?0.74, p?<?0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35?±?0.02 for 0R vs. 0.45?±?0, p?<?0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τic) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings. 相似文献
73.
Matthieu Jabaudon Raiko Blondonnet Bruno Pereira Rodrigo Cartin-Ceba Christoph Lichtenstern Tommaso Mauri Rogier M. Determann Tomas Drabek Rolf D. Hubmayr Ognjen Gajic Florian Uhle Andrea Coppadoro Antonio Pesenti Marcus J. Schultz Marco V. Ranieri Helena Brodska Ségolène Mrozek Vincent Sapin Michael A. Matthay Jean-Michel Constantin Carolyn S. Calfee 《Intensive care medicine》2018,44(9):1388-1399
Purpose
The soluble receptor for advanced glycation end-products (sRAGE) is a marker of lung epithelial injury and alveolar fluid clearance (AFC), with promising values for assessing prognosis and lung injury severity in acute respiratory distress syndrome (ARDS). Because AFC is impaired in most patients with ARDS and is associated with higher mortality, we hypothesized that baseline plasma sRAGE would predict mortality, independently of two key mediators of ventilator-induced lung injury.Methods
We conducted a meta-analysis of individual data from 746 patients enrolled in eight prospective randomized and observational studies in which plasma sRAGE was measured in ARDS articles published through March 2016. The primary outcome was 90-day mortality. Using multivariate and mediation analyses, we tested the association between baseline plasma sRAGE and mortality, independently of driving pressure and tidal volume.Results
Higher baseline plasma sRAGE [odds ratio (OR) for each one-log increment, 1.18; 95% confidence interval (CI) 1.01–1.38; P?=?0.04], driving pressure (OR for each one-point increment, 1.04; 95% CI 1.02–1.07; P?=?0.002), and tidal volume (OR for each one-log increment, 1.98; 95% CI 1.07–3.64; P?=?0.03) were independently associated with higher 90-day mortality in multivariate analysis. Baseline plasma sRAGE mediated a small fraction of the effect of higher ΔP on mortality but not that of higher VT.Conclusions
Higher baseline plasma sRAGE was associated with higher 90-day mortality in patients with ARDS, independently of driving pressure and tidal volume, thus reinforcing the likely contribution of alveolar epithelial injury as an important prognostic factor in ARDS. Registration: PROSPERO (ID: CRD42018100241).74.
Simon Rauch Tomas Dal Cappello Giacomo Strapazzon Martin Palma Francesco Bonsante Elisabeth Gruber Mathias Ströhle Peter Mair Hermann Brugger 《The American journal of emergency medicine》2018,36(10):1749-1753
Objective
We investigated pre-hospital times, clinical characteristics and therapeutic interventions in multisystem trauma patients injured in mountainous areas in comparison to both urban and suburban trauma patient admissions.Methods
Pre-hospital and in-hospital data collected from trauma patients included in the International Alpine Trauma Register (IATR) hosted in Bolzano, Italy (aged 16–80?yr with an ISS?≥?16), were compared with trauma patient data published from those urban and suburban areas included in the Trauma Register DGU® (TR-DGU) of the German Trauma Society.Results
A total of 94 patients from the IATR and 11,020 patients from the TR-DGU met the inclusion criteria. Due to longer treatment-free intervals (mean 59.1 vs. 19.7?min), total out-of-hospital time was reportedly longer in individuals injured in mountainous areas, compared to urban/suburban areas (117.4?±?142.9 vs. 68.7?±?28.6?min, p?=?0.002), despite the more frequent helicopter rescue (93% vs. 40%, p?<?0.001). 57% of IATR patients were hypothermic at hospital arrival, mean ISS was higher (38.5?±?15.8 vs. 28.6?±?12.2, p?<?0.001) and patients with a systolic blood pressure (SBP) ≤90?mm?Hg were more frequent (27% vs. 15%, p?=?0.005), yet less patients had received volume therapy (82% vs. 93%, p?=?0.001). However, overall no difference in hospital mortality was observed (11% vs. 17%, p?=?0.159).Conclusion
Trauma incidents in mountainous areas commonly feature significantly increased out-of-hospital time which is associated with a more severe ISS, higher risk of accidental hypothermia and more frequent hypotension compared to urban/suburban trauma. Nonetheless, the mortality rate of IATR patients is comparable to urban/suburban trauma patients. 相似文献75.
76.
The anatomy of electrochemical flow microreactors is important to safely perform chemical reactions in order to obtain pure and high yielding substances in a controlled and precise way that excludes the use of supporting electrolytes. Flow microreactors are advantageous in handling unstable intermediates compared to batch techniques and have efficient heat/mass transfer. Electrode nature (cathode and anode) and their available exposed surface area to the reaction mixture, parameters of the spacer, flow rate and direction greatly affects the efficiency of the electrochemical reactor. Solid formation during reactions may result in a blockage and consequently decrease the overall yield, thus limiting the use of microreactors in the field of electrosynthesis. This problem could certainly be overcome by application of ultrasound to break the solids for consistent flow. In this review, we discuss in detail the aforementioned issues, the advances in microreactor technology for chemical synthesis, with possible application of sonochemistry to deal with solid formations. Various examples of flow methods for electrosynthesis through microreactors have been explained in this review, which would definitely help to meet future demands for efficient synthesis and production of various pharmaceuticals and fine chemicals.The advances in flow microreactor technology for chemical synthesis, with possible application of sonochemistry to deal with solid formations. 相似文献
77.
Although in many cardiac surgery centers pharmacological strategies based on fibrinolytic inhibitors are used on a routine basis, detailed knowledge of fibrinolysis during various settings of coronary surgery is still limited. Sixty-five patients scheduled for coronary surgery were randomized into 3 groups: group A--conventional coronary artery bypass grafting, group B--off-pump surgery, and group C--coronary artery bypass grafting with modified, rheoparin coated cardiopulmonary bypass with the avoidance of reinfusion of cardiotomy blood into the circuit. The sampling time points for rotation thromboelastographic evaluations were as follows: preoperatively, 15 minutes after sternotomy, on the completion of peripheral bypass anastomoses, at the end of the procedures, and 24 hours after the end of surgery. D-dimer levels were evaluated before surgery, at the end of procedures, and 24 hours after surgery. Thromboelastographic signs of fibrinolysis (evaluated by Lysis Onset Time-intergroup differences at 60 and 150 minutes of assessment: P = 0.003 and P < 0.001, respectively) were clearly detectable during cardiopulmonary bypass in group A, but not at any time in groups B and C. At the other sampling times all thromboelastographic parameters were similar in all groups. In group A, no exceptional bleeding tendency (during 24 hours), as compared to groups B and C (geometric means and 95% confidence intervals: group A: 686.7 [570.8; 826.1] mL, group B: 555.3 [441.3; 698.9] mL, group C: 775.6 [645.1; 932.3] mL, P = 0.157), and no significant correlations between Lysis Onset Time, postoperative blood loss, and D-dimer levels were found. No significant differences in postoperative blood loss related to cardiac surgeons and assistant surgeons were detected. Thromboelastographic signs of increased fibrinolysis were detectable in the important proportion of coronary surgery patients operated on with the use of conventional cardio-pulmonary bypass, but not in off-pump patients and those operated on with the biocompatible surface-modified circuit without reinfusion of cardiotomy suction blood. These signs resolved spontaneously at the end of surgery and were not associated with increased postoperative bleeding. No significant correlation with D-dimer levels was found. 相似文献
78.
Diane Purper-Ouakil Hilario Blasco-Fontecilla Tomas Ros Eric Acquaviva Tobias Banaschewski Sarah Baumeister Elisa Bousquet Aurore Bussalb Marie Delhaye Richard Delorme Renate Drechsler Allison Goujon Alexander Häge Anna Kaiser Louis Mayaud Konstantin Mechler Caroline Menache Olivier Revol Friederike Tagwerker Susanne Walitza Anna Maria Werling Stephanie Bioulac Daniel Brandeis 《Journal of child psychology and psychiatry, and allied disciplines》2022,63(2):187-198
79.
SIR, The aim of this letter is to show our experience in theuse of leflunomide (LFN) and express our opinion about the recommendeddose [1, 2]. As far as we know, no data exist about a possibleassociation between the loading dose and the presence of adverseevents. Any new suggestion about the use of LFN should be appreciated,specially after the safety of this 相似文献
80.
Vokurka J Olejnik J Jedlicka V Vesely M Ciernik J Paseka T 《Hepato-gastroenterology》2008,55(85):1349-1352
BACKGROUND/AIMS: Acute mesenteric ischemia (AMI) is a serious disease in old age with low incidence but with a very high mortality rate (60-70%). The etiology is either primary (embolism or thrombosis of mesenteric arteries or veins, non-occlusive mesenteric ischemia) or secondary (mechanical obstruction such as intestinal volvulus, intussusception, tumor-caused compression). Independent of the origin of the illness, the clinical-pathological picture is the same: intestinal ischemia with subsequent necrosis. The aim of this study was to ascertain which underlying conditions lead to increased probability of development of acute mesenteric ischemia. METHODS: Two hundred and fifteen patients with a primary form of AMI were treated in the years 1991-2007, in the 1st Clinic of Surgery in Brno, Czech Republic and in the Department of General Surgery, Derer's University Hospital in Bratislava, Slovak Republic; the results of the treatment have been statistically evaluated. CONCLUSION: The probability of arterial mesenteric ischemia development rises significantly (p < 0.05) in patients with a history of atrial fibrillation and/or myocardial infarction. This probability is also significantly higher in smokers with symptoms of hypertension and clinical signs of abdominal angina (p < 0.05). 相似文献