132 results on '"Jens, Meier"'
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2. Leitsymptome in der Notfallmedizin: Der praktische Weg zur Diagnose
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Martin Dünser, Roland Stöger, Michaela Klinglmair, and Jens Meier
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- 2023
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3. Neue Wege der Daseinsvorsorge: Digitalisierung der Lübecker Schulen durch die kommunalen Stadtwerke als Beitrag zu den UN-Nachhaltigkeitszielen
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Farina Steinert, Jenny Scharfe, Jens Meier, and Kevin Kleinert
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Die Bereitstellung von öffentlichen Dienstleistungen im Rahmen der kommunalen Daseinsvorsorge befindet sich in einem weitreichenden Umbruch. Ausgelöst durch die Digitalisierung und hiermit einhergehenden gesellschaftlichen Wandel müssen neue Wege gefunden werden, ein zeitgemäßes Angebot von Daseinsvorsorge auch im digitalen Raum bereitzustellen. Am Beispiel der Digitalisierung der Lübecker Schulen durch die Stadtwerke Lübeck Gruppe belegen die Autor:innen, dass sich eine neue Säule moderner Daseinsvorsorge etablieren muss. Digitale Infrastruktur, Datenmanagement und die Vermittlung von Know-How im Umgang mit digitalen Medien sind elementare Bausteine einer hierfür notwendigen „Digitalen Daseinsvorsorge“. Dies zahlt auf mehrere Sustainable Development Goals (SDG) ein.
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- 2023
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4. The value of a machine learning algorithm to predict adverse short-term outcome during resuscitation of patients with in-hospital cardiac arrest: a retrospective study
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Martin W. Dünser, David Hirschl, Birgit Weh, Jens Meier, and Thomas Tschoellitsch
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Emergency Medicine - Published
- 2023
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5. The Austrian ICU survey
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Christine Schlömmer, Gregor A. Schittek, Jens Meier, Walter Hasibeder, Andreas Valentin, and Martin W. Dünser
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General Medicine - Published
- 2022
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6. Impact of the occurrence probability of carbon black agglomerates on the measured and predicted durability of filled elastomers
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Mohammed El Yaagoubi and Jens Meier
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Materials science ,Polymers and Plastics ,Agglomerate ,Occurrence probability ,Monte Carlo method ,Materials Chemistry ,Fracture mechanics ,General Chemistry ,Carbon black ,Composite material ,Elastomer ,Durability ,Stress concentration - Published
- 2021
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7. Individualized Management of Coagulopathy in Patients with End-Stage Liver Disease
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Tina Tomić Mahečić, Robert Baronica, Anna Mrzljak, Ana Boban, Ivona Hanžek, Dora Karmelić, Anđela Babić, Slobodan Mihaljević, and Jens Meier
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cirrhosis ,Clinical Biochemistry ,portal hypertension ,ESLD ,viscoelastic tests ,coagulopathy - Abstract
Over the last decades, individualized approaches and a better understanding of coagulopathy complexity in end-stage liver disease (ESLD) patients has evolved. The risk of both thrombosis and bleeding during minimally invasive interventions or surgery is associated with a worse outcome in this patient population. Despite deranged quantitative and qualitative coagulation laboratory parameters, prophylactic coagulation management is unnecessary for patients who do not bleed. Transfusion of red blood cells (RBCs) and blood products carries independent risks for morbidity and mortality, including modulation of the immune system with increased risk for nosocomial infections. Optimal coagulation management in these complex patients should be based on the analysis of standard coagulation tests (SCTs) and viscoelastic tests (VETs). VETs represent an individualized approach to patients and can provide information about coagulation dynamics in a concise period of time. This narrative review will deliver the pathophysiology of deranged hemostasis in ESLD, explore the difficulties of evaluating the coagulopathies in liver disease patients, and examine the use of VET assays and management of coagulopathy using coagulation factors. Methods: A selective literature search with PubMed as the central database was performed with the following.
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- 2022
8. qSOFA score poorly predicts critical progression in COVID-19 patients
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Sven Heldt, Christian Paar, Thomas Tschoellitsch, Bernhard Kaiser, Markus Winkler, Matthias Neuböck, Bernd Lamprecht, Guangyu Shao, Helmut J. F. Salzer, Jens Meier, Nora Kainzbauer, and Martin Duenser
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Adult ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Organ Dysfunction Scores ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Pilot Projects ,Risk management tools ,030204 cardiovascular system & hematology ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,law ,Sepsis ,Internal medicine ,medicine ,Humans ,Intensive care unit ,Österreich ,Hospital Mortality ,030212 general & internal medicine ,Retrospective Studies ,Oxygen saturation (medicine) ,Score für Organdysfunktion ,SARS-CoV-2 ,Tod ,business.industry ,Mortality rate ,COVID-19 ,General Medicine ,Prognosis ,Intensivstation ,Death ,Intensive Care Units ,Austria ,Original Article ,business ,Clinical risk factor - Abstract
In December 2019, the new virus infection coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged. Simple clinical risk scores may improve the management of COVID-19 patients. Therefore, the aim of this pilot study was to evaluate the quick Sequential Organ Failure Assessment (qSOFA) score, which is well established for other diseases, as an early risk assessment tool predicting a severe course of COVID-19.We retrospectively analyzed data from adult COVID-19 patients hospitalized between March and July 2020. A critical disease progress was defined as admission to intensive care unit (ICU) or death.Of 64 COVID-19 patients, 33% (21/64) had a critical disease progression from which 13 patients had to be transferred to ICU. The COVID-19-associated mortality rate was 20%, increasing to 39% after ICU admission. All patients without a critical progress had a qSOFA score ≤ 1 at admission. Patients with a critical progress had in only 14% (3/21) and in 20% (3/15) of cases a qSOFA score ≥ 2 at admission (p = 0.023) or when measured directly before critical progression, respectively, while 95% (20/21) of patients with critical progress had an impairment oxygen saturation (SOA low qSOFA score cannot be used to assume short-term stable or noncritical disease status in COVID-19.GRUNDLAGEN: Im Dezember 2019 kam es zum Auftreten der neuen Virusinfektion „coronavirus disease 2019“ (COVID-19), hervorgerufen durch das „severe acute respiratory syndrome coronavirus 2“ (SARS-CoV-2). Einfache klinische Scores zur frühzeitigen Risikostratifizierung könnten das Management von COVD-19-Patient(inn)en verbessern. Ziel dieser Pilotstudie war es daher, den für andere Erkrankungen etablierten qSOFA-Score („quick sequential organ failure assessment score“) als frühzeitige Risikobewertung für kritische Krankheitsverläufe bei COVID-19 zu evaluieren.Es erfolgte eine retrospektive Datenanalyse von hospitalisierten COVID-19-Patient(inn)en aus dem Zeitraum März bis Juli 2020. Ein kritischer Krankheitsverlauf wurde als Aufnahme auf die Intensivstation (ICU) oder Tod definiert.Von 64 COVID-19-Erkrankten wiesen 33 % (21/64) einen kritischen Krankheitsverlauf auf, wovon 13 Patient(inn)en auf die ICU verlegt wurden. Die COVID-19-assoziierte Sterblichkeitsrate betrug 20 % und stieg nach ICU-Aufnahme auf 39 % an. Bei allen Patient(inn)en ohne kritischen Verlauf war bei Aufnahme der qSOFA-Score ≤ 1. Patient(inn)en mit einem kritischen Verlauf hatten in nur 14 % (3/21) der Fälle bei Aufnahme (p = 0,023) bzw. in 20 % (3/15) der Fälle direkt vor kritischer Verschlechterung einen qSOFA-Score ≥ 2, wohingegen 95 % (20/21) der Patienten und Patientinnen mit einem kritischen Verlauf zum Zeitpunkt der Aufnahme eine reduzierte Sauerstoffsättigung (SOBei einem niedrigen qSOFA-Score kann nicht von einem kurzfristig stabilen oder unkritischen Krankheitsverlauf von COVID-19 ausgegangen werden.
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- 2021
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9. Crack growth angle prediction of an internal crack under mixed mode load for unfilled elastomer using the strain energy density factor
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Mohammed El Yaagoubi and Jens Meier
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Materials science ,Polymers and Plastics ,Materials Chemistry ,Strain energy density function ,General Chemistry ,Composite material ,Mixed mode ,Elastomer - Published
- 2021
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10. Machine learning-based prediction of fainting during blood donations using donor properties and weather data as features
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Susanne Suessner, Norbert Niklas, Ulrich Bodenhofer, and Jens Meier
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Machine Learning ,Health Policy ,Humans ,Blood Donors ,Health Informatics ,Weather ,Syncope ,Retrospective Studies ,Computer Science Applications - Abstract
Background and objectives Fainting is a well-known side effect of blood donation. Such adverse experiences can diminish the return rate for further blood donations. Identifying factors associated with fainting could help prevent adverse incidents during blood donation. Materials and methods Data of 85,040 blood donations from whole blood and apheresis donors within four consecutive years were included in this retrospective study. Seven different machine learning models (random forests, artificial neural networks, XGradient Boosting, AdaBoost, logistic regression, K nearest neighbors, and support vector machines) for predicting fainting during blood donation were established. The used features derived from the data obtained from the questionnaire every donor has to fill in before the donation and weather data of the day of the donation. Results One thousand seven hundred fifteen fainting reactions were observed in 228 846 blood donations from 88,003 donors over a study period of 48 months. Similar values for all machine learning algorithms investigated for NPV, PPV, AUC, and F1-score were obtained. In general, NPV was above 0.996, whereas PPV was below 0.03. AUC and F1-score were close to 0.9 for all models. Essential features predicting fainting during blood donation were systolic and diastolic blood pressure and ambient temperature, humidity, and barometric pressure. Conclusion Machine-learning algorithms can establish prediction models of fainting in blood donors. These new tools can reduce adverse reactions during blood donation and improve donor safety and minimize negative associations relating to blood donation.
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- 2022
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11. The Limits of Acute Anemia
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Tina Tomić Mahečić, Roxane Brooks, Matthias Noitz, Ignacio Sarmiento, Robert Baronica, and Jens Meier
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General Medicine - Abstract
For many years, physicians’ approach to the transfusion of allogeneic red blood cells (RBC) was not individualized. It was accepted that a hemoglobin concentration (Hb) of less than 10 g/dL was a general transfusion threshold and the majority of patients were transfused immediately. In recent years, there has been increasing evidence that even significantly lower hemoglobin concentrations can be survived in the short term without sequelae. This somehow contradicts the observation that moderate or mild anemia is associated with relevant long-term morbidity and mortality. To resolve this apparent contradiction, it must be recognized that we have to avoid acute anemia or treat it by alternative methods. The aim of this article is to describe the physiological limits of acute anemia, match these considerations with clinical realities, and then present “patient blood management” (PBM) as the therapeutic concept that can prevent both anemia and unnecessary transfusion of RBC concentrates in a clinical context, especially in Intensive Care Units (ICU). This treatment concept may prove to be the key to high-quality patient care in the ICU setting in the future.
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- 2022
12. Blood flow but not cannula positioning influences the efficacy of Veno-Venous ECMO therapy
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Massimiliano, Leoni, Johannes, Szasz, Jens, Meier, and Luca, Gerardo-Giorda
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Oxygen ,Extracorporeal Membrane Oxygenation ,Hemodynamics ,Humans ,Cannula ,COVID-19 - Abstract
Despite being vital in treating intensive-care patients with lung failure, especially COVID-19 patients, Veno-Venous Extra-Corporeal Membrane Oxygenation does not exploit its full potential, leaving ample room for improvement. The objective of this study is to determine the effect of cannula positioning and blood flow on the efficacy of Veno-Venous Extra-Corporeal Membrane Oxygenation, in particular in relationship with blood recirculation. We performed 98 computer simulations of blood flow and oxygen diffusion in a computerized-tomography-segmented right atrium and venae cavae for different positions of the returning and draining cannulae and ECMO flows of 3 L/min and [Formula: see text]. For each configuration we measured how effective Veno-Venous Extra-Corporeal Membrane Oxygenation is at delivering oxygen to the right ventricle and thus to the systemic circulation. The main finding is that VV-ECMO efficacy is largely affected by the ECMO flow (global peak blood saturation: [Formula: see text]; average inter-group saturation gain: 9 percentage points) but only scarcely by the positioning of the cannulae (mean saturation ± standard deviation for the 3 L/min case: [Formula: see text]; for the [Formula: see text] case: [Formula: see text]). An important secondary outcome is that recirculation, more intense with a higher ECMO flow, is less detrimental to the procedure than previously thought. The efficacy of current ECMO procedures is intrinsically limited and fine-tuning the positions of the cannulae, risking infections, offers very little gain. Setting a higher ECMO flow offers the biggest benefit despite mildly increasing blood recirculation.
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- 2022
13. Machine learning-based prediction of massive perioperative allogeneic blood transfusion in cardiac surgery
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Thomas Tschoellitsch, Carl Böck, Tina Tomić Mahečić, Axel Hofmann, and Jens Meier
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Adult ,Machine Learning ,Anesthesiology and Pain Medicine ,Hematopoietic Stem Cell Transplantation ,Humans ,Blood Transfusion ,Female ,Cardiac Surgical Procedures ,Retrospective Studies - Abstract
Massive perioperative allogeneic blood transfusion, that is, perioperative transfusion of more than 10 units of packed red blood cells (pRBC), is one of the main contributors to perioperative morbidity and mortality in cardiac surgery. Prediction of perioperative blood transfusion might enable preemptive treatment strategies to reduce risk and improve patient outcomes while reducing resource utilisation. We, therefore, investigated the precision of five different machine learning algorithms to predict the occurrence of massive perioperative allogeneic blood transfusion in cardiac surgery at our centre.Is it possible to predict massive perioperative allogeneic blood transfusion using machine learning?Retrospective, observational study.Single adult cardiac surgery centre in Austria between 01 January 2010 and 31 December 2019.Patients undergoing cardiac surgery.Primary outcome measures were the number of patients receiving at least 10 units pRBC, the area under the curve for the receiver operating characteristics curve, the F1 score, and the negative-predictive (NPV) and positive-predictive values (PPV) of the five machine learning algorithms used to predict massive perioperative allogeneic blood transfusion.A total of 3782 (1124 female:) patients were enrolled and 139 received at least 10 pRBC units. Using all features available at hospital admission, massive perioperative allogeneic blood transfusion could be excluded rather accurately. The best area under the curve was achieved by Random Forests: 0.810 (0.76 to 0.86) with high NPV of 0.99). This was still true using only the eight most important features [area under the curve 0.800 (0.75 to 0.85)].Machine learning models may provide clinical decision support as to which patients to focus on for perioperative preventive treatment in order to preemptively reduce massive perioperative allogeneic blood transfusion by predicting, which patients are not at risk.Johannes Kepler University Ethics Committee Study Number 1091/2021, Clinicaltrials.gov identifier NCT04856618.
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- 2022
14. Standards and Best Practice for Acute Normovolemic Hemodilution: Evidence-based Consensus Recommendations
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Aryeh Shander, Phillipe Van der Linden, Jens Meier, Sherri Ozawa, Marc Licker, Seth I. Perelman, James P Brown, David Mazer, and Pierre R. Tibi
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medicine.medical_specialty ,Consensus ,Evidence-based practice ,Blood management ,Blood transfusion ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,law.invention ,Likert scale ,03 medical and health sciences ,0302 clinical medicine ,030202 anesthesiology ,law ,Anesthesiology ,Cardiopulmonary bypass ,Humans ,Medicine ,Cardiac Surgical Procedures ,Hemodilution ,Cardiopulmonary Bypass ,business.industry ,Reference Standards ,Cardiac surgery ,Anesthesiology and Pain Medicine ,Perfusionist ,Emergency medicine ,Cardiology and Cardiovascular Medicine ,business - Abstract
Objective To develop a standardized approach to the implementation and performance of acute normovolemic hemodilution (ANH) in order to reduce the incidence of bleeding and allogeneic blood transfusion in high-risk surgical bleeding-related cardiac surgery with cardiopulmonary bypass (CPB). Design A 2-round modified RAND-Delphi consensus process. Participants Seven physicians from multiple geographic locations and clinical disciplines including anesthesiology and cardiac surgery and 1 cardiac surgery perfusionist participated in the survey. One registered nurse, specializing in Patient Blood Management, participated in the discussion but did not participate in the survey. Methods A modified RAND-Delphi method was utilized that integrated evidence review with a face-to-face expert multidisciplinary panel meeting, followed by repeated scoring using a 9-point Likert scale. Consensus was determined as a result from the second round survey, as follows: median rating of 1-3: ANH acceptable; median rating of 7-9: ANH not acceptable; median rating of 4-6: use clinical judgment. Results Evidentiary review identified 18 key peer-reviewed manuscripts for discussion. Through the consensus-building process, 39 statements including 26 contraindications to ANH and 10 CPB patient variables were assessed. In total, 22 statements were accepted or modified for the second scoring round. Conclusions Consensus was reached on 6 conditions in which ANH would or would not be acceptable, showing that development of a standardized approach for the use of ANH in high-risk surgical bleeding and allogeneic blood transfusion is clearly possible. The recommendations developed by this expert panel may help guide the management and inclusion of ANH as an evidence and consensus-based blood conservation modality.
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- 2020
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15. Essential Role of Patient Blood Management in a Pandemic: A Call for Action
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Aryeh Shander, Anna Mezzacasa, Elvira Bisbe, Sherri Ozawa, Sigismond Lasocki, Johann Kurz, Steven M. Frank, Vernon J. Louw, Nicole R. Guinn, Axel Hofmann, Wayne B. Dyer, Susan M. Goobie, Shannon L Farmer, Jens Meier, Daryl J. Kor, Matthew A. Warner, Jeannie Callum, Hans Gombotz, Donat R. Spahn, Kevin M Trentino, Marco Pavesi, Young Woo Kim, Thorsten Haas, Ángel Augusto Pérez-Calatayud, Jackie Thomson, David Faraoni, Manuel Muñoz, Jochen Erhard, Christoph Zenger, Mazyar Javidroozi, Bruce D. Spiess, Bernd Froessler, Melissa M. Cushing, Irwin Gross, Matti Aapro, Jeong Jae Lee, Hongwen Ji, Jeffrey M. Hamdorf, Nina Shander, James P. Isbister, Michael F. Leahy, Cheuk-Kwong Lee, Tatyana Fedorova, University of Zurich, and Shander, Aryeh
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medicine.medical_specialty ,Blood management ,Blood transfusion ,10216 Institute of Anesthesiology ,business.industry ,medicine.medical_treatment ,Public health ,COVID-19 ,610 Medicine & health ,Evidence-based medicine ,Call to action ,Coronavirus ,Special Article ,Anesthesiology and Pain Medicine ,Pandemic ,Global health ,Medicine ,10220 Clinic for Surgery ,2703 Anesthesiology and Pain Medicine ,General Articles ,business ,Intensive care medicine ,Personal protective equipment - Abstract
The World Health Organization (WHO) has declared Coronavirus Disease 2019 (COVID-19), the disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a pandemic. Global health care now faces unprecedented challenges with widespread and rapid human-to-human transmission of SARS-CoV-2 and high morbidity and mortality with COVID-19 worldwide. Across the world, medical care is hampered by a critical shortage of not only hand sanitizers, personal protective equipment, ventilators, and hospital beds, but also impediments to the blood supply. Blood donation centers in many areas around the globe have mostly closed. Donors, practicing social distancing, some either with illness or undergoing self-quarantine, are quickly diminishing. Drastic public health initiatives have focused on containment and “flattening the curve” while invaluable resources are being depleted. In some countries, the point has been reached at which the demand for such resources, including donor blood, outstrips the supply. Questions as to the safety of blood persist. Although it does not appear very likely that the virus can be transmitted through allogeneic blood transfusion, this still remains to be fully determined. As options dwindle, we must enact regional and national shortage plans worldwide and more vitally disseminate the knowledge of and immediately implement patient blood management (PBM). PBM is an evidence-based bundle of care to optimize medical and surgical patient outcomes by clinically managing and preserving a patient’s own blood. This multinational and diverse group of authors issue this “Call to Action” underscoring “The Essential Role of Patient Blood Management in the Management of Pandemics” and urging all stakeholders and providers to implement the practical and commonsense principles of PBM and its multiprofessional and multimodality approaches.
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- 2020
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16. Domain Shifts in Machine Learning Based Covid‐19 Diagnosis From Blood Tests
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Theresa Roland, Carl Böck, Thomas Tschoellitsch, Alexander Maletzky, Sepp Hochreiter, Jens Meier, and Günter Klambauer
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Machine Learning ,COVID-19 Testing ,Hematologic Tests ,Health Information Management ,Medicine (miscellaneous) ,COVID-19 ,Humans ,Reproducibility of Results ,Health Informatics ,Information Systems - Abstract
Many previous studies claim to have developed machine learning models that diagnose COVID-19 from blood tests. However, we hypothesize that changes in the underlying distribution of the data, so called domain shifts, affect the predictive performance and reliability and are a reason for the failure of such machine learning models in clinical application. Domain shifts can be caused, e.g., by changes in the disease prevalence (spreading or tested population), by refined RT-PCR testing procedures (way of taking samples, laboratory procedures), or by virus mutations. Therefore, machine learning models for diagnosing COVID-19 or other diseases may not be reliable and degrade in performance over time. We investigate whether domain shifts are present in COVID-19 datasets and how they affect machine learning methods. We further set out to estimate the mortality risk based on routinely acquired blood tests in a hospital setting throughout pandemics and under domain shifts. We reveal domain shifts by evaluating the models on a large-scale dataset with different assessment strategies, such as temporal validation. We present the novel finding that domain shifts strongly affect machine learning models for COVID-19 diagnosis and deteriorate their predictive performance and credibility. Therefore, frequent re-training and re-assessment are indispensable for robust models enabling clinical utility.
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- 2022
17. Machine Learning-Based Mortality Prediction of Patients at Risk During Hospital Admission
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Kevin M. Trentino, Karin Schwarzbauer, Andreas Mitterecker, Axel Hofmann, Adam Lloyd, Michael F. Leahy, Thomas Tschoellitsch, Carl Böck, Sepp Hochreiter, and Jens Meier
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Adult ,Hospitalization ,Machine Learning ,Leadership and Management ,Public Health, Environmental and Occupational Health ,Humans ,Hospital Mortality ,Risk Assessment ,Hospitals ,Retrospective Studies - Abstract
The ability to predict in-hospital mortality from data available at hospital admission would identify patients at risk and thereby assist hospital-wide patient safety initiatives. Our aim was to use modern machine learning tools to predict in-hospital mortality from standardized data sets available at hospital admission.This was a retrospective, observational study in 3 adult tertiary care hospitals in Western Australia between January 2008 and June 2017. Primary outcome measures were the area under the curve for the receiver operating characteristics curve, the F1 score, and the average precision of the 4 machine learning algorithms used: logistic regression, neural networks, random forests, and gradient boosting trees.Using our 4 predictive models, in-hospital mortality could be predicted satisfactorily (areas under the curve for neural networks, logistic regression, random forests, and gradient boosting trees: 0.932, 0.936, 0.935, and 0.935, respectively), with moderate F1 scores: 0.378, 0.367, 0.380, and 0.380, respectively. Average precision values were 0.312, 0.321, 0.334, and 0.323, respectively. It remains unknown whether additional features might improve our models; however, this would result in additional efforts for data acquisition in daily clinical practice.This study demonstrates that using only a limited, standardized data set in-hospital mortality can be predicted satisfactorily at the time point of hospital admission. More parameters describing patient's health are likely needed to improve our model.
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- 2022
18. Diagnostic Quality Assessment for Low-Dimensional ECG Representations
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Péter Kovács, Carl Böck, Thomas Tschoellitsch, Mario Huemer, and Jens Meier
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Signal Processing (eess.SP) ,J.3 ,G.3 ,I.6.4 ,FOS: Electrical engineering, electronic engineering, information engineering ,Health Informatics ,62P10, 92C55, 41A30, 42C05 ,Electrical Engineering and Systems Science - Signal Processing ,Computer Science Applications - Abstract
There have been several attempts to quantify the diagnostic distortion caused by algorithms that perform low-dimensional electrocardiogram (ECG) representation. However, there is no universally accepted quantitative measure that allows the diagnostic distortion arising from denoising, compression, and ECG beat representation algorithms to be determined. Hence, the main objective of this work was to develop a framework to enable biomedical engineers to efficiently and reliably assess diagnostic distortion resulting from ECG processing algorithms. We propose a semiautomatic framework for quantifying the diagnostic resemblance between original and denoised/reconstructed ECGs. Evaluation of the ECG must be done manually, but is kept simple and does not require medical training. In a case study, we quantified the agreement between raw and reconstructed (denoised) ECG recordings by means of kappa-based statistical tests. The proposed methodology takes into account that the observers may agree by chance alone. Consequently, for the case study, our statistical analysis reports the "true", beyond-chance agreement in contrast to other, less robust measures, such as simple percent agreement calculations. Our framework allows efficient assessment of clinically important diagnostic distortion, a potential side effect of ECG (pre-)processing algorithms. Accurate quantification of a possible diagnostic loss is critical to any subsequent ECG signal analysis, for instance, the detection of ischemic ST episodes in long-term ECG recordings.
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- 2022
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19. Epidemiology and Outcome of Sepsis in Adults and Children in a Rural, Sub-Sahara African Setting
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Arthur, Kwizera, Olivier, Urayeneza, Pierre, Mujyarugamba, Inipavudu, Baelani, Jens, Meier, Mervyn, Mer, Ndidiamaka, Musa, Niranjan, Kissoon, Andrew J, Patterson, Joseph C, Farmer, and Martin W, Dünser
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sepsis ,Africa ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,malaria ,outcome ,Rwanda ,epidemiology ,Original Clinical Report - Abstract
Supplemental Digital Content is available in the text., OBJECTIVES: To identify the epidemiology and outcome of adults and children with and without sepsis in a rural sub-Sahara African setting. DESIGN: A priori planned substudy of a prospective, before-and-after trial. SETTING: Rural, sub-Sahara African hospital. PATIENTS: One-thousand four-hundred twelve patients (adults, n = 491; children, n = 921) who were admitted to hospital because of an acute infection. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Demographic, clinical, laboratory data, danger signs, and the presence of sepsis (defined as a quick Sequential Organ Failure Assessment score count ≥ 2) at admission were extracted. Sepsis was observed in 69 adults (14.1%) and 248 children (26.9%). Sepsis patients differed from subjects without sepsis in several demographic and clinical aspects. Malaria was the most frequent type of infection in adults (66.7%) and children (63.7%) with sepsis, followed by suspected bacterial and parasitic infections other than malaria. Adults with sepsis more frequently developed respiratory failure (8.7% vs 2.1%; p = 0.01), had a higher in-hospital mortality (17.4% vs 8.3%; p < 0.001), were less often discharged home (81.2% vs 92.2%; p = 0.007), and had higher median (interquartile range) costs of care (30,300 [19,400–49,900] vs 42,500 Rwandan Francs [27,000–64,400 Rwandan Francs]; p = 0.004) than adults without sepsis. Children with sepsis were less frequently discharged home than children without sepsis (93.1% vs 96.4%; p = 0.046). Malaria and respiratory tract infections claimed the highest absolute numbers of lives. The duration of symptoms before hospital admission did not differ between survivors and nonsurvivors in adults (72 [24–168] vs 96 hr [72–168 hr]; p = 0.27) or children (48 [24–72] vs 36 [24–108 hr]; p = 0.8). Respiratory failure and coma were the most common causes of in-hospital death. CONCLUSIONS: In addition to suspected bacterial, viral, and fungal infections, malaria and other parasitic infections are common and important causes of sepsis in adults and children admitted to a rural hospital in sub-Sahara Africa. The in-hospital mortality associated with sepsis is substantial, primarily in adults.
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- 2021
20. Variability of expert assessments of ECG time domain parameters
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Carl Böck, Christoph Mörtl, Christoph Mahringer, Mario Huemer, and Jens Meier
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- 2023
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21. Friction behaviors of rice husk silica-reinforced elastomer composites in contact with rough self-affine surfaces
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Bumyong Yoon, Sungwon Kim, Andrej Lang, Christian Egelkamp, Jens Meier, Ulrich Giese, Baekhwan Kim, Jun Hong Kim, Jong Woo Bae, Gi Yong Um, Seong Hye Kim, Do Il Kim, Sun Jung Kim, and Jonghwan Suhr
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Polymers and Plastics ,Organic Chemistry - Published
- 2022
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22. Color classification of visually evoked potentials by means of Hermite functions
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Tamas Dozsa, Carl Bock, Gergo Bognar, Jens Meier, and Peter Kovacs
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- 2021
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23. Open Heart Surgery in Jehovah’s Witnesses: A Propensity Score Analysis
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Andreas Zierer, Wolfgang Schimetta, Thomas Ratschiller, Hans Gombotz, Hannes Müller, and Jens Meier
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Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Blood management ,Anemia ,030204 cardiovascular system & hematology ,Hematocrit ,03 medical and health sciences ,0302 clinical medicine ,Preoperative Care ,Humans ,Medicine ,Cardiac Surgical Procedures ,Propensity Score ,Erythropoietin ,Jehovah's Witnesses ,Aged ,Retrospective Studies ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Retrospective cohort study ,Perioperative ,Middle Aged ,medicine.disease ,Cardiac surgery ,Surgery ,Treatment Outcome ,030228 respiratory system ,Propensity score matching ,Female ,Hemoglobin ,Cardiology and Cardiovascular Medicine ,business - Abstract
Jehovah's Witnesses (JW) refuse allogeneic blood transfusions and therefore pose a unique challenge in case of major surgery. This retrospective study reviewed an experience with JW patients who were undergoing open heart surgery.By using patient blood management strategies, 35 adult JW patients underwent cardiac surgery at Kepler University Hospital in Linz, Austria between 2008 and 2017. Outcomes were compared with patients who accepted blood transfusions (non-JW patients) by using propensity score matching.There were no significant differences in clinical and operative data between the groups. Twelve JW patients (34.3%) were pretreated with erythropoietin and iron, with a preoperative increase in mean hemoglobin of 2.0 g/dL. On admission, hemoglobin was 14.1 ± 1.1 g/dL in JW patients, compared with 13.2 ± 2.0 g/dL in non-JW patients (P = .022). The hematocrit in JW patients was higher throughout the hospital stay, even though 51.4% of non-JW patients received allogeneic red blood cell transfusions. The perioperative red blood cell loss was significantly lower in JW patients than in non-JW patients (619 ± 420 mL vs 929 ± 520 mL; P = .010). Major complication rates were not different between the groups. The hemoglobin at discharge was 11.5 ± 1.5 g/dL in JW patients compared with 10.3 ± 1.3 g/dL in non-JW patients (P.001). In-hospital mortality was 2.9% in each group, and long-term survival was comparable.By implementing patient blood management, open heart surgery in JW patients can be performed with low morbidity and mortality. Preoperative optimization of hemoglobin and minimization of perioperative blood loss are cornerstones in the prevention of blood loss, anemia, and transfusions.
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- 2020
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24. RBC Transfusion Triggers: Is There Anything New?
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Martin W. Dünser, Jens Meier, and Tina Tomic Mahecic
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Rbc transfusion ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Anemia ,Organ dysfunction ,Review Article ,Hematology ,030204 cardiovascular system & hematology ,Hematocrit ,medicine.disease ,Time optimal ,Clinical Practice ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Immunology and Allergy ,Acute anemia ,medicine.symptom ,Intensive care medicine ,business ,Adverse effect ,030215 immunology - Abstract
For many years, in daily clinical practice, the traditional 10/30 rule (hemoglobin 10 g/dL – hematocrit 30%) has been the most commonly used trigger for blood transfusions. Over the years, this approach is believed to have contributed to a countless number of unnecessary transfusions and an unknown number of overtransfusion-related deaths. Recent studies have shown that lower hemoglobin levels can safely be accepted, even in critically ill patients. However, even these new transfusion thresholds are far beyond the theoretical limits of individual anemia tolerance. For this reason, almost all publications addressing the limits of acute anemia recommend physiological transfusion triggers to indicate the transfusion of erythrocyte concentrates as an alternative. Although this concept appears intuitive at first glance, no solid scientific evidence supports the safety and benefit of physiological transfusion triggers to indicate the optimal time point for transfusion of allogeneic blood. It is therefore imperative to continue searching for the most sensitive and specific parameters that can guide the clinician when to transfuse in order to avoid anemia-induced organ dysfunction while avoiding overtransfusion-related adverse effects. This narrative review discusses the concept of anemia tolerance and critically compares hemoglobin-based triggers with physiological transfusion for various clinical indications.
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- 2020
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25. Patient Blood Management
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Jens Meier
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Anesthesiology and Pain Medicine ,General Medicine - Published
- 2022
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26. Traumaassoziierte Koagulopathie: Pathophysiologie und Therapie
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Christine Schlömmer and Jens Meier
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Gynecology ,medicine.medical_specialty ,business.industry ,030208 emergency & critical care medicine ,General Medicine ,Critical Care and Intensive Care Medicine ,Pathophysiology ,03 medical and health sciences ,0302 clinical medicine ,Anesthesiology and Pain Medicine ,Emergency Medicine ,medicine ,030212 general & internal medicine ,business ,Trauma induced coagulopathy - Abstract
ZusammenfassungDie anhaltende unkontrollierte Blutung ist eine der führenden Todesursachen bei polytraumatisierten Patienten 1, 2, 3, 4, 5. Hypoperfusion durch große Blutverluste führt zu Gewebeschäden, generalisierter Immunantwort sowie Aktivierung des Gerinnungssystems und damit zu einer traumaassoziierten Koagulopathie (TAK) 4, 5. Durch eine adäquate, frühzeitige Behandlung der TAK können Morbidität und Mortalität signifikant reduziert werden.
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- 2019
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27. Lifetime prediction of simple shear loaded filled elastomers based on the probability distribution of particles
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Hamid El Maanaoui, Mohammed El Yaagoubi, Jens Meier, and Oliver Gehrmann
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Work (thermodynamics) ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Monte Carlo method ,02 engineering and technology ,Mechanics ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Elastomer ,01 natural sciences ,0104 chemical sciences ,Simple shear ,Fracture (geology) ,Probability distribution ,Deformation (engineering) ,0210 nano-technology ,Realization (probability) - Abstract
A new method of the end-of-life prediction for filled elastomers has been introduced and applied on fatigue under uniaxial deformations in [1]. The method considers measured inhomogeneity size frequencies. The dimension of these inhomogeneities is assumed to be equal to the sizes of the initial cracks responsible for the final end-of-life of the elastomer. For an end-of-life prediction, the initial crack size information is inserted into a standard fracture mechanic law. Within a Monte Carlo simulation, several spatial realization steps of statistical initial crack size distributions over the deformation field of the investigated component or specimen are performed. Within each realization step, the minimum number of cycles until end-of-life is extracted and supplies a failure probability plot. Performing a large number of realizations provides the complete failure probability information. In this work, that concept is applied on fatigue under simple shear. The predicted failure probability values match the experimental findings from dynamic fatigue tests for the considered Styrene Rubber.
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- 2019
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28. Lifting Hospital Electronic Health Record Data Treasures: Challenges and Opportunities
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Alexander Maletzky, Carl Böck, Thomas Tschoellitsch, Theresa Roland, Helga Ludwig, Stefan Thumfart, Michael Giretzlehner, Sepp Hochreiter, and Jens Meier
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Health Information Management ,Health Informatics - Abstract
Electronic health records (EHRs) have been successfully used in data science and machine learning projects. However, most of these data are collected for clinical use rather than for retrospective analysis. This means that researchers typically face many different issues when attempting to access and prepare the data for secondary use. We aimed to investigate how raw EHRs can be accessed and prepared in retrospective data science projects in a disciplined, effective, and efficient way. We report our experience and findings from a large-scale data science project analyzing routinely acquired retrospective data from the Kepler University Hospital in Linz, Austria. The project involved data collection from more than 150,000 patients over a period of 10 years. It included diverse data modalities, such as static demographic data, irregularly acquired laboratory test results, regularly sampled vital signs, and high-frequency physiological waveform signals. Raw medical data can be corrupted in many unexpected ways that demand thorough manual inspection and highly individualized data cleaning solutions. We present a general data preparation workflow, which was shaped in the course of our project and consists of the following 7 steps: obtain a rough overview of the available EHR data, define clinically meaningful labels for supervised learning, extract relevant data from the hospital’s data warehouses, match data extracted from different sources, deidentify them, detect errors and inconsistencies therein through a careful exploratory analysis, and implement a suitable data processing pipeline in actual code. Only few of the data preparation issues encountered in our project were addressed by generic medical data preprocessing tools that have been proposed recently. Instead, highly individualized solutions for the specific data used in one’s own research seem inevitable. We believe that the proposed workflow can serve as a guidance for practitioners, helping them to identify and address potential problems early and avoid some common pitfalls.
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- 2022
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29. Intraoperative transfusion practices and perioperative outcome in the European elderly: A secondary analysis of the observational ETPOS study
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Grusser L., Keszei A., Coburn M., Rossaint R., Ziemann S., Kowark A, Daniela Filipescu, Sibylle Kozek-Langenecker, Juan V Llau Pitarch, Susan Mallett, Peter Martus, Idit Matot, Jens Meier, Axel Unterrainer, Dieter Adelmann, Daniel von Langen, Petra Innerhofer, Nicole Innerhofer-Pompernigg, Stefan De Hert, Luc De Baerdemaeker, Jurgen van Limmen, Piet Wyffels, Björn Heyse, Margot Vanderlaenen, Maud Beran, David Kahn, Audrey Prospiech, Luc Jamaer, Freya Mulders, Stefan Jacobs, Wannes Baeten, Sofie Platteau, Isabelle Maquoi, Severine Lauwick, Marc Senard, Vincent Ninane, Jean-Pierre Lecoq, Pierre Boveroux, Grégory Hans, Marcel Vercauteren, Brigitte Leva, Benoit Plichon, Vojislav Vujanovič, Ismet Suljevic, Hened Kelle, Denis Gustin, Matea Bogdanovic Dvorscak, Tamara Lupis, Jadranka Pavičić Šarić, Nataša Paklar, Dagmar Oberhofer, Ira Skok, Borana Kirigin, Ikic Visnja, Marina Kresic, Slavica Kvolik, Renatas Krobot, Vladimir Cerny, Jana Striteska, Marcela Bilska, Petr Štourač, Hana Harazim, Olga Smékalová, Martina Kosinová, Jozef Klučka, Rita Pacasová, Kim Ekelund, Indrek Rätsep, Juri Oganjan, Nadezda Smirnova, Peeter Kivik, Juri Karjagin, Alar Rokk, Alar Sõrmus, Bertrand Rozec, Jean-Christophe Rigal, Jean-Pierre Gouraud, Anne-Marie Chupin, Xavier Ambrosi, Laurent Brisard, Sylvie Decagny, Charles Marc Samama, Lionel Lidzborski, Matthieu Boisson, Anne-Laure Arcade, Gilbert Lorre, Peter Rosenberger, Hannah Merz, Ulrich Goebel, Bettina Schnitter, Hartmut Buerkle, Roland Tomasi, Vera von Dossow-Hanfstingl, Florian Brettner, Andreas Bayer, André Gottschalk, Nicolas Jakobs, Mark Coburn, Ana Kowark, Rolf Rossaint, Rita Laufenberg, Marion Ferner, Michael Schuster, Lydia Strys, Susanne Mauff, Kornel Skitek, Ewa Zielinska-Skitek, Gregor Schittek, Andreas Hoeft, Andreas Fleischer, Maria Wittmann, Florian Kessler, Anne Rohner, Peter Kranke, Christian Wunder, Johanna Jokinen, Kristin Budow, Christopher Prasser, Eva Werner, Alina Balandin, Norbert Ahrens, Kai Zacharowski, Patrick Meybohm, Kassiani Theodoraki, George Giokas, Tasoulis Marios-Konstantinos, Ageliki Pandazi, Aikaterini Kyttari, Eygenia Koursoumi, Georgios Anthopoulos, Antonis Andreou, Athanasios Rantis, Dimitrios Valsamidis, Pelagia Klimi, Konstantinos Katsanoulas, Demetrios Korfiotis, Christos Soumelidis, Fotios Papaspyros, Olga Kiskira, Tilemachos Paraskeuopoulos, Donal Buggy, Mortimer Kelleher, Liz Coghlan, Vladimir Verenkin, Anat Cattan, Francesco Bona, Felicino Debernardi, Andrea Cortegiani, Santi Maurizio Raineri, Giuseppe Accurso, Elena Gramigni, Leonardo Cenni, Laura Campiglia, Irene Lorenzi, Maria Grazia Militello, Tamara Biscioni, Andrius Macas, Daiva Apanaviciute, Darius Trepenaitis, Arunas Gelmanas, Diana Bilshiene, Jurate Sipylaite, Gabija Tomkute, Egle Kontrimaviciut, Renatas Tikuisis, Francis Borg, Ion Chesov, Serghei Cobiletchi, Victoria Moghildea, Bas Verdouw, J F van Poorten, Nick van Dasselaar, Marcus Daniel Lance, Britta de Waal, Lucienne Kropman, Peter van Noord, Benedikt Preckel, Lena Koers, Markus W Hollmann, Holger Baumann, Ankie W M M Koopman-van Gemert, Tore Reikvam, Tore Hervig, Kasper Gymoese Berthelsen, Ingvild Hausberg Sørvoll, Mirosław Czuczwar, Michał Borys, Paweł Piwowarczyk, Suzana Parente, Diogo Martins, Gloria Tareco, Ligia Reis, Joana Amaral, Daniel Ferreira, José Manuel Gonçalves Aguiar, Zélia Moreira, Filipa Lagarto, Filipa Pereira, Maria Lina Miranda, Sofia Serra, Alexandre Carrilho, José Pinto, Sandra Dias, Rita Poeria, Filipe Linda, Silvia Pica, Helder Martinho, Francisco Matias, Claudia Alves, Valentina Almeida, Margarida Marques, Emilia Martires, Piedade Gomes, Elizabete Pereira, Joana Jesus, Claudia Carreira, Carlos Seco, Carlos Bento, Helena Vieira, Luciane Pereira, Fernando Pinto, Luisa Silva, Marta Azenha, Maged Zarif, Ana Bernardino, Ana Raimundo, Ana Lopes, Melissa Fernandes, Beatriz Campos, Ana Macedo, Filipe Pinheiro, Sonia Duarte, Alexandra Saraiva, Catia Real, Marilena Alina Paunescu, Alexandru Bogdan Prodan, Mihai Stefan, Cristian Boros, Marius Tifrea, Anca Dragan, Horhota Lucian, Alida Moise, Carmen Arion-Balescu, Natalia Mincu, Viorel Gherghina, Iulia Cindea, Dan Costea, Ravzan Popescu, Dana Tomescu, Ecaterina Scarlatescu, Esenia Calancea, Ruxandra Copotoiu, Sanda Maria Copotoiu, Victoria Barsan, Dan Corneci, Rely Manolescu, Toma Diana, Denisa Nitu, Georgian Popica, Gabriela Droc, Nicoleta Jipa Lavina, Roxana Ciobanasu, Anna Maria Munteanu, Denisa Anastase, Iona Grintescu, Liliana Mirea, Alexandra Manoleli, Ciobanu Elena, Mary Nicoleta Lupu, Madalina Nina Sandu, Bicolae Bacalbasa, Florenta Calarasu, Alexey Grytsan, Andrey Gasenkampf, Alexander Kulikov, Alexander Shmigelsky, Vojislava Nescovic, Rade Vukovic, Uros Petrovic, Milic Veljovic, Dragana Unic-Stojanovic, Gordana Jovanovic, Ivana Kvrgic, Dragana Rakic, Roman Záhorec, Daniel Cintula, Tomas Veselovsky, Katarina Galkova, Jordana Stevikova, Andrea Číková, Zora Flassikova, Anna Dobisova, Jasmina Markovic Bozic, Minca Voje, Andriy Grynyuk, Alenka Spindler Yesel, Sabina Stivan, Peter Poredos, Darja Kasnik, Jasna Uranjek, Raquel Ferrandis, Sofia Machado, Liliana Henao, Tania Moreno, Ana Izquierdo, Carlos Delgado, Angela Camps, Susana Manrique, Alejandro Arbelaez, Pilar Tormos, Helena Serrano, Irene Garcia, Elvira Bisbe Vives, Luís Moltó, Tania Villar, Enrique Moret, Raquel Tolós, Esther Martínez, Misericordia Basora, Beatriz Tena, Roger Pujol, Jorge Vera Bella, Thomas Mallor, Pablo Mondero, Luis Lopez, Francisco Hidalgo, Maria Bermudez Lopez, Ana Velasco, Begona Bascuas, Victoria Moral, Diana Gómez Martinez, Alfredo Merten, J A Fernández, Nadia Diana Kinast, A Font, Maggi Genaro, Emilia Guasch, Fernando Gilsanz, Raul Martinez, Renato Schiraldi, Ever Martinez, Marta Barquero López, Alexo Lopez Alvarez, Yvan Enrique Sanchez Sanchez, Adriana Roman Fernandez, Olalla Varela Garcia, Marian Angeles Orallo Moran, Veronica Gonzalez Monzon, Óscar Sánchez López, David Sanchez Perez, Pablo Molano Diaz, Concepcion Cassinello, Maria Pilar Jubera, Maria Soler Pedrola, Julio Belmonte Cuenca, Sören Söndergaard, Till Rudolph, Kristin Åkeröy, Monir Jawad, Yousif Saeed, Sergej Safonov, Mona Andersson, Jan Wernerman, Suzanne Odeberg-Wernerman, Tommi Blom, Nesil Deger Coskunfirat, Zekiye Bigat, Suat Sanlı, O Koray Coskunfirat, Atilla Ramazanoğlu, Neval Boztug Uz, Ali Emre Camci, Omur Aksoy, Esra Saka, Oguzhan Arun, Sevda Ozkardesler, Dilek Omur, Mert Akan, Zuleyha Kazak Bengisun, Hakan Yılmaz, Perihan Ekmekci, Onur Selvi, Neslihan Alkis, Çiğdem Yıldırım, Başak Ceyda Meço, Zekeriyye Alanoğlu, Sergiy Vorotyntsev, Yevgen Yakymenko, Galina Troyan, Mohammed Alousi, Sarah James, Paula Meale, Ahmed Chishti, Matt Garner, Rita Singh, Nicola Hirschauer, Charley Higham, Andrea Bell, Alistair Cain, Chris Perry, Katy Davies, Claire Leech, Verity Calder, Shaman Jhanji, Varma Sandeep, Karen Simeson, Philip Watt, Nigel Dunk, Rosemary Ferrie, Margaret Wright, Lynn Everett, Andrew Ferguson, Laura Espie, Gail Browne, Matthew Dickinson, Ashok Nair, Deborah Clements, Peter Carvalho, Thomas Collyer, Jens Bolten, Lajos Zsisku, Attila Petri, Mohammed Ramadan, Tracey Ellimah, Martus, Peter, Laufenberg, Rita, Ferner, Marion, Schuster, Michael, Strys, Lydia, Mauff, Susanne, Skitek, Kornel, Zielinska-Skitek, Ewa, Schittek, Gregor, Hoeft, Andreas, Fleischer, Andreas, Matot, Idit, Wittmann, Maria, Kessler, Florian, Rohner, Anne, Kranke, Peter, Wunder, Christian, Jokinen, Johanna, Budow, Kristin, Prasser, Christopher, Werner, Eva, Balandin, Alina, Meier, Jens, Ahrens, Norbert, Zacharowski, Kai, Meybohm, Patrick, Theodoraki, Kassiani, Giokas, George, Marios-Konstantinos, Tasoulis, Pandazi, Ageliki, Kyttari, Aikaterini, Koursoumi, Eygenia, Anthopoulos, Georgios, Unterrainer, Axel, Andreou, Antonis, Rantis, Athanasios, Valsamidis, Dimitrios, Klimi, Pelagia, Katsanoulas, Konstantinos, Korfiotis, Demetrios, Soumelidis, Christos, Papaspyros, Fotios, Kiskira, Olga, Paraskeuopoulos, Tilemachos, Adelmann, Dieter, Buggy, Donal, Kelleher, Mortimer, Coghlan, Liz, Verenkin, Vladimir, Cattan, Anat, Bona, Francesco, Debernardi, Felicino, Cortegiani, Andrea, Raineri, Santi Maurizio, Accurso, Giuseppe, von Langen, Daniel, Gramigni, Elena, Cenni, Leonardo, Campiglia, Laura, Lorenzi, Irene, Militello, Maria Grazia, Biscioni, Tamara, Macas, Andrius, Apanaviciute, Daiva, Trepenaitis, Darius, Gelmanas, Arunas, Innerhofer, Petra, Bilshiene, Diana, Sipylaite, Jurate, Tomkute, Gabija, Kontrimaviciut, Egle, Tikuisis, Renatas, Borg, Francis, Chesov, Ion, Cobiletchi, Serghei, Moghildea, Victoria, Verdouw, Bas, Innerhofer-Pompernigg, Nicole, van Poorten, J. F., van Dasselaar, Nick, Lance, Marcus Daniel, de Waal, Britta, Kropman, Lucienne, van Noord, Peter, Preckel, Benedikt, Koers, Lena, Hollmann, Markus W., Baumann, Holger, De Hert, Stefan, Koopman-van Gemert, Ankie W. M. M., Reikvam, Tore, Hervig, Tore, Berthelsen, Kasper Gymoese, Sørvoll, Ingvild Hausberg, Czuczwar, Mirosław, Borys, Michał, Piwowarczyk, Paweł, Parente, Suzana, Martins, Diogo, De Baerdemaeker, Luc, Tareco, Gloria, Reis, Ligia, Amaral, Joana, Ferreira, Daniel, Gonçalves Aguiar, José Manuel, Moreira, Zélia, Lagarto, Filipa, Pereira, Filipa, Miranda, Maria Lina, Serra, Sofia, van Limmen, Jurgen, Carrilho, Alexandre, Pinto, José, Dias, Sandra, Poeria, Rita, Linda, Filipe, Pica, Silvia, Martinho, Helder, Matias, Francisco, Alves, Claudia, Almeida, Valentina, Wyffels, Piet, Marques, Margarida, Martires, Emilia, Gomes, Piedade, Pereira, Elizabete, Jesus, Joana, Carreira, Claudia, Seco, Carlos, Bento, Carlos, Vieira, Helena, Pereira, Luciane, Heyse, Björn, Pinto, Fernando, Silva, Luisa, Azenha, Marta, Zarif, Maged, Bernardino, Ana, Raimundo, Ana, Lopes, Ana, Fernandes, Melissa, Campos, Beatriz, Macedo, Ana, Vanderlaenen, Margot, Pinheiro, Filipe, Duarte, Sonia, Saraiva, Alexandra, Real, Catia, Paunescu, Marilena Alina, Bogdan Prodan, Alexandru, Stefan, Mihai, Boros, Cristian, Tifrea, Marius, Dragan, Anca, Beran, Maud, Lucian, Horhota, Moise, Alida, Arion-Balescu, Carmen, Mincu, Natalia, Gherghina, Viorel, Cindea, Iulia, Costea, Dan, Popescu, Ravzan, Tomescu, Dana, Scarlatescu, Ecaterina, Kahn, David, Calancea, Esenia, Copotoiu, Ruxandra, Copotoiu, Sanda Maria, Barsan, Victoria, Corneci, Dan, Manolescu, Rely, Diana, Toma, Nitu, Denisa, Popica, Georgian, Droc, Gabriela, Prospiech, Audrey, Jipa Lavina, Nicoleta, Ciobanasu, Roxana, Munteanu, Anna Maria, Anastase, Denisa, Grintescu, Iona, Mirea, Liliana, Manoleli, Alexandra, Elena, Ciobanu, Lupu, Mary Nicoleta, Sandu, Madalina Nina, Jamaer, Luc, Bacalbasa, Bicolae, Calarasu, Florenta, Grytsan, Alexey, Gasenkampf, Andrey, Kulikov, Alexander, Shmigelsky, Alexander, Nescovic, Vojislava, Vukovic, Rade, Petrovic, Uros, Veljovic, Milic, Mulders, Freya, Unic-Stojanovic, Dragana, Jovanovic, Gordana, Kvrgic, Ivana, Rakic, Dragana, Záhorec, Roman, Cintula, Daniel, Veselovsky, Tomas, Galkova, Katarina, Stevikova, Jordana, Číková, Andrea, Jacobs, Stefan, Flassikova, Zora, Dobisova, Anna, Markovic Bozic, Jasmina, Voje, Minca, Grynyuk, Andriy, Spindler Yesel, Alenka, Stivan, Sabina, Poredos, Peter, Kasnik, Darja, Uranjek, Jasna, Baeten, Wannes, Ferrandis, Raquel, Machado, Sofia, Henao, Liliana, Moreno, Tania, Izquierdo, Ana, Delgado, Carlos, Camps, Angela, Manrique, Susana, Arbelaez, Alejandro, Tormos, Pilar, Platteau, Sofie, Serrano, Helena, Garcia, Irene, Bisbe Vives, Elvira, Moltó, Luís, Villar, Tania, Moret, Enrique, Tolós, Raquel, Martínez, Esther, Basora, Misericordia, Tena, Beatriz, Maquoi, Isabelle, Pujol, Roger, Vera Bella, Jorge, Mallor, Thomas, Mondero, Pablo, Lopez, Luis, Hidalgo, Francisco, Bermudez Lopez, Maria, Velasco, Ana, Bascuas, Begona, Moral, Victoria, Lauwick, Severine, Gómez Martinez, Diana, Merten, Alfredo, Fernández, J. A., Kinast, Nadia Diana, Font, A., Genaro, Maggi, Guasch, Emilia, Gilsanz, Fernando, Martinez, Raul, Schiraldi, Renato, Senard, Marc, Martinez, Ever, Barquero López, Marta, Lopez Alvarez, Alexo, Sanchez Sanchez, Yvan Enrique, Roman Fernandez, Adriana, Varela Garcia, Olalla, Orallo Moran, Marian Angeles, Gonzalez Monzon, Veronica, Sánchez López, Óscar, Sanchez Perez, David, Ninane, Vincent, Molano Diaz, Pablo, Cassinello, Concepcion, Pilar Jubera, Maria, Soler Pedrola, Maria, Belmonte Cuenca, Julio, Söndergaard, Sören, Rudolph, Till, Åkeröy, Kristin, Jawad, Monir, Saeed, Yousif, Lecoq, Jean-Pierre, Safonov, Sergej, Andersson, Mona, Wernerman, Jan, Odeberg-Wernerman, Suzanne, Blom, Tommi, Deger Coskunfirat, Nesil, Bigat, Zekiye, Sanlı, Suat, Coskunfirat, O. Koray, Ramazanoğlu, Atilla, Boveroux, Pierre, Boztug Uz, Neval, Camci, Ali Emre, Aksoy, Omur, Saka, Esra, Arun, Oguzhan, Ozkardesler, Sevda, Omur, Dilek, Akan, Mert, Bengisun, Zuleyha Kazak, Yılmaz, Hakan, Hans, Grégory, Ekmekci, Perihan, Selvi, Onur, Alkis, Neslihan, Yıldırım, Çiğdem, Ceyda Meço, Başak, Alanoğlu, Zekeriyye, Vorotyntsev, Sergiy, Yakymenko, Yevgen, Troyan, Galina, Alousi, Mohammed, Vercauteren, Marcel, James, Sarah, Meale, Paula, Chishti, Ahmed, Garner, Matt, Singh, Rita, Hirschauer, Nicola, Higham, Charley, Bell, Andrea, Cain, Alistair, Perry, Chris, Leva, Brigitte, Davies, Katy, Leech, Claire, Calder, Verity, Jhanji, Shaman, Sandeep, Varma, Simeson, Karen, Watt, Philip, Dunk, Nigel, Ferrie, Rosemary, Wright, Margaret, Plichon, Benoit, Everett, Lynn, Ferguson, Andrew, Espie, Laura, Browne, Gail, Dickinson, Matthew, Nair, Ashok, Clements, Deborah, Carvalho, Peter, Collyer, Thomas, Bolten, Jens, Vujanovič, Vojislav, Zsisku, Lajos, Petri, Attila, Ramadan, Mohammed, Ellimah, Tracey, Suljevic, Ismet, Kelle, Hened, Gustin, Denis, Bogdanovic Dvorscak, Matea, Lupis, Tamara, Pavičić Šarić, Jadranka, Paklar, Nataša, Oberhofer, Dagmar, Skok, Ira, Kirigin, Borana, Visnja, Ikic, Kresic, Marina, Kvolik, Slavica, Krobot, Renatas, Cerny, Vladimir, Striteska, Jana, Bilska, Marcela, Filipescu, Daniela, Štourač, Petr, Harazim, Hana, Smékalová, Olga, Kosinová, Martina, Klučka, Jozef, Pacasová, Rita, Ekelund, Kim, Rätsep, Indrek, Oganjan, Juri, Smirnova, Nadezda, Kozek-Langenecker, Sibylle, Kivik, Peeter, Karjagin, Juri, Rokk, Alar, Sõrmus, Alar, Rozec, Bertrand, Rigal, Jean-Christophe, Gouraud, Jean-Pierre, Chupin, Anne-Marie, Ambrosi, Xavier, Brisard, Laurent, Llau Pitarch, Juan V., Decagny, Sylvie, Samama, Charles Marc, Lidzborski, Lionel, Boisson, Matthieu, Arcade, Anne-Laure, Lorre, Gilbert, Rosenberger, Peter, Merz, Hannah, Goebel, Ulrich, Schnitter, Bettina, Mallett, Susan, Buerkle, Hartmut, Tomasi, Roland, von Dossow-Hanfstingl, Vera, Brettner, Florian, Bayer, Andreas, Gottschalk, André, Jakobs, Nicolas, Coburn, Mark, Kowark, Ana, Rossaint, Rolf, Grusser L., Keszei A., Coburn M., Rossaint R., Ziemann S., Kowark A, Daniela Filipescu, Sibylle Kozek-Langenecker, Juan V Llau Pitarch, Susan Mallett, Peter Martus, Idit Matot, Jens Meier, Axel Unterrainer, Dieter Adelmann, Daniel von Langen, Petra Innerhofer, Nicole Innerhofer-Pompernigg, Stefan De Hert, Luc De Baerdemaeker, Jurgen van Limmen, Piet Wyffels, Björn Heyse, Margot Vanderlaenen, Maud Beran, David Kahn, Audrey Prospiech, Luc Jamaer, Freya Mulders, Stefan Jacobs, Wannes Baeten, Sofie Platteau, Isabelle Maquoi, Severine Lauwick, Marc Senard, Vincent Ninane, Jean-Pierre Lecoq, Pierre Boveroux, Grégory Hans, Marcel Vercauteren, Brigitte Leva, Benoit Plichon, Vojislav Vujanovič, Ismet Suljevic, Hened Kelle, Denis Gustin, Matea Bogdanovic Dvorscak, Tamara Lupis, Jadranka Pavičić Šarić, Nataša Paklar, Dagmar Oberhofer, Ira Skok, Borana Kirigin, Ikic Visnja, Marina Kresic, Slavica Kvolik, Renatas Krobot, Vladimir Cerny, Jana Striteska, Marcela Bilska, Petr Štourač, Hana Harazim, Olga Smékalová, Martina Kosinová, Jozef Klučka, Rita Pacasová, Kim Ekelund, Indrek Rätsep, Juri Oganjan, Nadezda Smirnova, Peeter Kivik, Juri Karjagin, Alar Rokk, Alar Sõrmus, Bertrand Rozec, Jean-Christophe Rigal, Jean-Pierre Gouraud, Anne-Marie Chupin, Xavier Ambrosi, Laurent Brisard, Sylvie Decagny, Charles Marc Samama, Lionel Lidzborski, Matthieu Boisson, Anne-Laure Arcade, Gilbert Lorre, Peter Rosenberger, Hannah Merz, Ulrich Goebel, Bettina Schnitter, Hartmut Buerkle, Roland Tomasi, Vera von Dossow-Hanfstingl, Florian Brettner, Andreas Bayer, André Gottschalk, Nicolas Jakobs, Mark Coburn, Ana Kowark, Rolf Rossaint, Rita Laufenberg, Marion Ferner, Michael Schuster, Lydia Strys, Susanne Mauff, Kornel Skitek, Ewa Zielinska-Skitek, Gregor Schittek, Andreas Hoeft, Andreas Fleischer, Maria Wittmann, Florian Kessler, Anne Rohner, Peter Kranke, Christian Wunder, Johanna Jokinen, Kristin Budow, Christopher Prasser, Eva Werner, Alina Balandin, Norbert Ahrens, Kai Zacharowski, Patrick Meybohm, Kassiani Theodoraki, George Giokas, Tasoulis Marios-Konstantinos, Ageliki Pandazi, Aikaterini Kyttari, Eygenia Koursoumi, Georgios Anthopoulos, Antonis Andreou, Athanasios Rantis, Dimitrios Valsamidis, Pelagia Klimi, Konstantinos Katsanoulas, Demetrios Korfiotis, Christos Soumelidis, Fotios Papaspyros, Olga Kiskira, Tilemachos Paraskeuopoulos, Donal Buggy, Mortimer Kelleher, Liz Coghlan, Vladimir Verenkin, Anat Cattan, Francesco Bona, Felicino Debernardi, Andrea Cortegiani, Santi Maurizio Raineri, Giuseppe Accurso, Elena Gramigni, Leonardo Cenni, Laura Campiglia, Irene Lorenzi, Maria Grazia Militello, Tamara Biscioni, Andrius Macas, Daiva Apanaviciute, Darius Trepenaitis, Arunas Gelmanas, Diana Bilshiene, Jurate Sipylaite, Gabija Tomkute, Egle Kontrimaviciut, Renatas Tikuisis, Francis Borg, Ion Chesov, Serghei Cobiletchi, Victoria Moghildea, Bas Verdouw, J F van Poorten, Nick van Dasselaar, Marcus Daniel Lance, Britta de Waal, Lucienne Kropman, Peter van Noord, Benedikt Preckel, Lena Koers, Markus W Hollmann, Holger Baumann, Ankie W M M Koopman-van Gemert, Tore Reikvam, Tore Hervig, Kasper Gymoese Berthelsen, Ingvild Hausberg Sørvoll, Mirosław Czuczwar, Michał Borys, Paweł Piwowarczyk, Suzana Parente, Diogo Martins, Gloria Tareco, Ligia Reis, Joana Amaral, Daniel Ferreira, José Manuel Gonçalves Aguiar, Zélia Moreira, Filipa Lagarto, Filipa Pereira, Maria Lina Miranda, Sofia Serra, Alexandre Carrilho, José Pinto, Sandra Dias, Rita Poeria, Filipe Linda, Silvia Pica, Helder Martinho, Francisco Matias, Claudia Alves, Valentina Almeida, Margarida Marques, Emilia Martires, Piedade Gomes, Elizabete Pereira, Joana Jesus, Claudia Carreira, Carlos Seco, Carlos Bento, Helena Vieira, Luciane Pereira, Fernando Pinto, Luisa Silva, Marta Azenha, Maged Zarif, Ana Bernardino, Ana Raimundo, Ana Lopes, Melissa Fernandes, Beatriz Campos, Ana Macedo, Filipe Pinheiro, Sonia Duarte, Alexandra Saraiva, Catia Real, Marilena Alina Paunescu, Alexandru Bogdan Prodan, Mihai Stefan, Cristian Boros, Marius Tifrea, Anca Dragan, Horhota Lucian, Alida Moise, Carmen Arion-Balescu, Natalia Mincu, Viorel Gherghina, Iulia Cindea, Dan Costea, Ravzan Popescu, Dana Tomescu, Ecaterina Scarlatescu, Esenia Calancea, Ruxandra Copotoiu, Sanda Maria Copotoiu, Victoria Barsan, Dan Corneci, Rely Manolescu, Toma Diana, Denisa Nitu, Georgian Popica, Gabriela Droc, Nicoleta Jipa Lavina, Roxana Ciobanasu, Anna Maria Munteanu, Denisa Anastase, Iona Grintescu, Liliana Mirea, Alexandra Manoleli, Ciobanu Elena, Mary Nicoleta Lupu, Madalina Nina Sandu, Bicolae Bacalbasa, Florenta Calarasu, Alexey Grytsan, Andrey Gasenkampf, Alexander Kulikov, Alexander Shmigelsky, Vojislava Nescovic, Rade Vukovic, Uros Petrovic, Milic Veljovic, Dragana Unic-Stojanovic, Gordana Jovanovic, Ivana Kvrgic, Dragana Rakic, Roman Záhorec, Daniel Cintula, Tomas Veselovsky, Katarina Galkova, Jordana Stevikova, Andrea Číková, Zora Flassikova, Anna Dobisova, Jasmina Markovic Bozic, Minca Voje, Andriy Grynyuk, Alenka Spindler Yesel, Sabina Stivan, Peter Poredos, Darja Kasnik, Jasna Uranjek, Raquel Ferrandis, Sofia Machado, Liliana Henao, Tania Moreno, Ana Izquierdo, Carlos Delgado, Angela Camps, Susana Manrique, Alejandro Arbelaez, Pilar Tormos, Helena Serrano, Irene Garcia, Elvira Bisbe Vives, Luís Moltó, Tania Villar, Enrique Moret, Raquel Tolós, Esther Martínez, Misericordia Basora, Beatriz Tena, Roger Pujol, Jorge Vera Bella, Thomas Mallor, Pablo Mondero, Luis Lopez, Francisco Hidalgo, Maria Bermudez Lopez, Ana Velasco, Begona Bascuas, Victoria Moral, Diana Gómez Martinez, Alfredo Merten, J A Fernández, Nadia Diana Kinast, A Font, Maggi Genaro, Emilia Guasch, Fernando Gilsanz, Raul Martinez, Renato Schiraldi, Ever Martinez, Marta Barquero López, Alexo Lopez Alvarez, Yvan Enrique Sanchez Sanchez, Adriana Roman Fernandez, Olalla Varela Garcia, Marian Angeles Orallo Moran, Veronica Gonzalez Monzon, Óscar Sánchez López, David Sanchez Perez, Pablo Molano Diaz, Concepcion Cassinello, Maria Pilar Jubera, Maria Soler Pedrola, Julio Belmonte Cuenca, Sören Söndergaard, Till Rudolph, Kristin Åkeröy, Monir Jawad, Yousif Saeed, Sergej Safonov, Mona Andersson, Jan Wernerman, Suzanne Odeberg-Wernerman, Tommi Blom, Nesil Deger Coskunfirat, Zekiye Bigat, Suat Sanlı, O Koray Coskunfirat, Atilla Ramazanoğlu, Neval Boztug Uz, Ali Emre Camci, Omur Aksoy, Esra Saka, Oguzhan Arun, Sevda Ozkardesler, Dilek Omur, Mert Akan, Zuleyha Kazak Bengisun, Hakan Yılmaz, Perihan Ekmekci, Onur Selvi, Neslihan Alkis, Çiğdem Yıldırım, Başak Ceyda Meço, Zekeriyye Alanoğlu, Sergiy Vorotyntsev, Yevgen Yakymenko, Galina Troyan, Mohammed Alousi, Sarah James, Paula Meale, Ahmed Chishti, Matt Garner, Rita Singh, Nicola Hirschauer, Charley Higham, Andrea Bell, Alistair Cain, Chris Perry, Katy Davies, Claire Leech, Verity Calder, Shaman Jhanji, Varma Sandeep, Karen Simeson, Philip Watt, Nigel Dunk, Rosemary Ferrie, Margaret Wright, Lynn Everett, Andrew Ferguson, Laura Espie, Gail Browne, Matthew Dickinson, Ashok Nair, Deborah Clements, Peter Carvalho, Thomas Collyer, Jens Bolten, Lajos Zsisku, Attila Petri, Mohammed Ramadan, Tracey Ellimah, Anesthesiology, ACS - Diabetes & metabolism, APH - Quality of Care, ACS - Heart failure & arrhythmias, APH - Global Health, and ACS - Microcirculation
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Clinical Oncology ,Male ,Science ,Clinical Decision-Making ,Cancer Treatment ,Surgical and Invasive Medical Procedures ,Geographical Locations ,Diagnostic Medicine ,Outcome Assessment, Health Care ,Medicine and Health Sciences ,Humans ,Blood Transfusion ,Prospective Studies ,Aged ,Aged, 80 and over ,Intraoperative Care ,Multidisciplinary ,Transfusion Medicine ,Anemia ,Hematology ,Clinical Laboratory Sciences ,Health Care ,Europe ,Surgical Oncology ,Oncology ,Age Groups ,Elective Surgical Procedures ,People and Places ,Medicine ,Population Groupings ,Female ,Geriatric Care ,Clinical Medicine ,Erythrocyte Transfusion ,Research Article - Abstract
PLOS ONE 17(1), e0262110 (2022). doi:10.1371/journal.pone.0262110, Published by PLOS, San Francisco, California, US
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- 2022
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30. Machine Learning based COVID-19 Diagnosis from Blood Tests with Robustness to Domain Shifts
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Roland T, Maletzky A, Sepp Hochreiter, Thomas Tschoellitsch, Günter Klambauer, Jens Meier, and Carl Bock
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2019-20 coronavirus outbreak ,education.field_of_study ,Coronavirus disease 2019 (COVID-19) ,Computer science ,Hospital setting ,business.industry ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Population ,Machine learning ,computer.software_genre ,Weighting ,Domain (software engineering) ,Robustness (computer science) ,Artificial intelligence ,business ,education ,computer - Abstract
We investigate machine learning models that identify COVID-19 positive patients and estimate the mortality risk based on routinely acquired blood tests in a hospital setting. However, during pandemics or new outbreaks, disease and testing characteristics change, thus we face domain shifts. Domain shifts can be caused, e.g., by changes in the disease prevalence (spreading or tested population), by refined RT-PCR testing procedures (taking samples, laboratory), or by virus mutations. Therefore, machine learning models for diagnosing COVID-19 or other diseases may not be reliable and degrade in performance over time. To countermand this effect, we propose methods that first identify domain shifts and then reverse their negative effects on the model performance. Frequent re-training and reassessment, as well as stronger weighting of more recent samples, keeps model performance and credibility at a high level over time. Our diagnosis models are constructed and tested on large-scale data sets, steadily adapt to observed domain shifts, and maintain high ROC AUC values along pandemics.
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- 2021
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31. Influence of the tensile static preload dependency on the dynamic lifetime prediction for an HNBR elastomer
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H. El Maanaoui, C. Egelkamp, and Jens Meier
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Materials science ,Biomedical Engineering ,030206 dentistry ,02 engineering and technology ,Edge (geometry) ,021001 nanoscience & nanotechnology ,Elastomer ,Biomaterials ,03 medical and health sciences ,Preload ,0302 clinical medicine ,Natural rubber ,Elastomers ,Mechanics of Materials ,visual_art ,Service life ,Ultimate tensile strength ,Tearing ,Materials Testing ,visual_art.visual_art_medium ,Dumbbell ,Composite material ,0210 nano-technology - Abstract
A correlated lifetime prediction concept for load cases without static preload, which argues with crack growth and particle size distribution from 3D computer tomography, has been shown by Ludwig et al. (2015). This method is extended to non-relaxing load cases i.e. with a static preload dependency. A force controlled dynamic fatigue test for a dumbbell specimen is performed to investigate the service life. In addition, a crack growth investigation is carried out using single edge notched tensile (SENT) specimens in displacement control mode to characterize the tearing energy and crack growth rate. The study with carbon black reinforced HNBR rubber shows a correlation between the Wohler curve and the Paris-Erdogan plot. An extension of the empirical Paris-Erdogan equation considering static preload dependency allows the prediction of uniaxial lifetime statistics by means of particle size distribution. The calculated lifetime values are in reasonable concordance with the experimental findings.
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- 2020
32. Machine learning-based risk profile classification of patients undergoing elective heart valve surgery
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Alexander Minichmayer, Georg Hermanutz, Jens Meier, Ulrich Bodenhofer, and Bettina Haslinger-Eisterer
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Heart disease ,030204 cardiovascular system & hematology ,Machine learning ,computer.software_genre ,Logistic regression ,Risk Assessment ,Machine Learning ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Cardiac Surgical Procedures ,Retrospective Studies ,Receiver operating characteristic ,business.industry ,Retrospective cohort study ,EuroSCORE ,General Medicine ,medicine.disease ,Heart Valves ,Cardiac surgery ,Random forest ,030228 respiratory system ,Cohort ,Surgery ,Artificial intelligence ,Cardiology and Cardiovascular Medicine ,business ,computer - Abstract
OBJECTIVES Machine learning methods potentially provide a highly accurate and detailed assessment of expected individual patient risk before elective cardiac surgery. Correct anticipation of this risk allows for the improved counselling of patients and avoidance of possible complications. We therefore investigated the benefit of modern machine learning methods in personalized risk prediction for patients undergoing elective heart valve surgery. METHODS We performed a monocentric retrospective study in patients who underwent elective heart valve surgery between 1 January 2008 and 31 December 2014 at our centre. We used random forests, artificial neural networks and support vector machines to predict the 30-day mortality from a subset of 129 available demographic and preoperative parameters. Exclusion criteria were reoperation of the same patient, patients who needed anterograde cerebral perfusion due to aortic arch surgery and patients with grown-up congenital heart disease. Finally, the cohort consisted of 2229 patients with a 30-day mortality of 3.86% (86 of 2229 cases). This trial has been registered at clinicaltrials.gov (NCT03724123). RESULTS The final random forest model trained on the entire data set provided an out-of-bag area under the receiver operator characteristics curve (AUC) of 0.839, which significantly outperformed the European System for Cardiac Operative Risk Evaluation (EuroSCORE) (AUC = 0.704) and a model trained only on the subset of features EuroSCORE uses (AUC = 0.745). CONCLUSIONS Advanced machine learning methods can predict outcomes of valve surgery procedures with higher accuracy than established risk scores based on logistic regression on pre-selected parameters. This approach is generalizable to other elective high-risk interventions and allows for training models to the cohorts of specific institutions
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- 2020
33. International point prevalence study of Intensive Care Unit transfusion practices-Pilot study in the Netherlands
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H. Schoechl, Simon Oczkowski, Jens Meier, M. Y. Alders, Matthias Müller, Anders Perner, Cécile Aubron, Gavin J. Murphy, M. Lance, Timothy S. Walsh, Maurizio Cecconi, Joanna C. Dionne, N. Nielsen, R. van Bruggen, Thomas Scheeren, Aarne Feldheiser, B. Hunt, S. de Bruin, Jacques Duranteau, Alexander P.J. Vlaar, M. Antonelli, Jan Bakker, Dirk de Korte, Graduate School, ACS - Pulmonary hypertension & thrombosis, AII - Inflammatory diseases, Human Genetics, Amsterdam Reproduction & Development (AR&D), Landsteiner Laboratory, ACS - Microcirculation, Intensive Care Medicine, Intensive Care, Critical care, Anesthesiology, Peri-operative and Emergency medicine (CAPE), Vascular Ageing Programme (VAP), Clinical Genetics, and Amsterdam Reproduction & Development
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Male ,BLOOD-TRANSFUSION ,Blood transfusion ,Internationality ,medicine.medical_treatment ,Clinical Biochemistry ,MULTICENTER ,University/statistics & numerical data ,Pilot Projects ,030204 cardiovascular system & hematology ,Hospitals, University/statistics & numerical data ,Red blood cells ,law.invention ,Hospitals, University ,Plasma ,0302 clinical medicine ,law ,Medicine ,Multicenter Studies as Topic ,Prospective Studies ,Netherlands ,education.field_of_study ,OUTCOMES ,Critical Care/methods ,Hematology ,Middle Aged ,Intensive care unit ,Hospitals ,Intensive Care Units ,Treatment Outcome ,Research Design ,Blood Component Transfusion/statistics & numerical data ,Female ,Fresh frozen plasma ,Cohort study ,Multicenter Studies as Topic/methods ,Platelets ,medicine.medical_specialty ,Critical Care ,Anemia ,Population ,PLATELET TRANSFUSION ,Blood Component Transfusion ,03 medical and health sciences ,Humans ,ANEMIA ,education ,Critically ill ,Diagnosis-Related Groups ,Aged ,business.industry ,CRITICALLY-ILL ,Biochemistry (medical) ,FRESH-FROZEN PLASMA ,RESTRICTIVE TRANSFUSION ,Guideline ,medicine.disease ,Platelet transfusion ,Emergency medicine ,Feasibility Studies ,Transfusion practice ,AUDIT ,business ,Procedures and Techniques Utilization ,030215 immunology - Abstract
Background. - Anaemia and coagulopathy are common issues in critically ill patients. Transfusion can be lifesaving, however, is associated with potential life threatening adverse events. As an international transfusion guideline for this specific patient population is lacking, we hypothesize that a high heterogeneity in transfusion practices exists. In this pilot-study we assessed transfusion practice in a university hospital in the Netherlands and tested the feasibility of this protocol for an international multi-centre study.Methods. - A prospective single centre cohort study was conducted. For seven days all consecutive non-readmitted patients to the adult Intensive Care Unit (ICU) were included and followed for 28 days. Patients were prospectively followed until ICU discharge or up to day 28. Patient outcome data was collected at day 28. Workload for this study protocol was scored in hours and missing data.Results. - In total, 48 patients were included, needed in total three hours patient to include and collect all data, with 1.6% missing data showing the feasibility of the data acquisition. Six (12.5%) patients received red blood cells (RBCs), three patients (6.3%) received platelet concentrates, and two (4.2%) patients received plasma units. In total eight (16.7%) patients were transfused with one or more blood products. Median pre- and post-transfusion haemoglobin (Hb) levels were 7.6 (6.7-7.7) g/dL and 8.1 (7.6-8.7) g/dL, respectively.Conclusion. - In this pilot-study we proved the feasibility of our protocol and observed in this small population a restrictive transfusion practice for all blood products. (C) 2019 Societe francaise de transfusion sanguine (SFTS). Published by Elsevier Masson SAS. All rights reserved.
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- 2019
34. Lifetime prediction of filled elastomers based on particle distribution and the J-integral evaluation
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Ulrich Giese, Nils Hendrik Kröger, Jens Meier, Daniel Juhre, Thomas Alshuth, and Mohammed El Yaagoubi
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J integral ,Materials science ,Computer simulation ,Mechanical Engineering ,Element by element ,Monte Carlo method ,02 engineering and technology ,Mechanics ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Elastomer ,01 natural sciences ,Industrial and Manufacturing Engineering ,Finite element method ,0104 chemical sciences ,Amplitude ,Mechanics of Materials ,Modeling and Simulation ,General Materials Science ,Total energy ,0210 nano-technology - Abstract
This work presents the lifetime prediction of elastomer component based on the particle distribution in the specimen, the crack growth properties and the appropriate crack criterion. A lifetime prediction using numerical simulation saves both cost and time and can be very helpful in the development phase of a product. On the basis of the obtained results, lifetime can be estimated and thus an appropriate measure such as geometry change or load adjustment can be adopted. The prediction is demonstrated using two kinds of elastomer samples: EPDM and NR under different load amplitudes. Lifetime prediction is accomplished by Monte Carlo simulation, which is based on the correlation between the value of J-integral and total energy density of the single-edge notched tension (SENT) sample. Due to the choice of an inelastic material law the J-integral is evaluated after establishment of stable load cycles as the stable value for a J-integral contour curve as a function of the contour curve distance from the crack tip. For lifetime prediction, a Python script was implemented for the commercial FEA system Abaqus as a postprocessing routine. The script is based on local lifetime evaluation, where evaluation is done element by element followed up by an accumulation. In addition, physical experiments are used for counting the particles in the materials, to characterise the crack growth and also to measure lifetime.
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- 2018
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35. 'Selbsthypnosetraining' bei chronischen stationären Schmerzpatienten
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C.L. Lassen, Christoph H.R. Wiese, Jens Meier, Bernhard M. Graf, Peter C. Keil, and Nicole Lindenberg
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Gynecology ,03 medical and health sciences ,medicine.medical_specialty ,0302 clinical medicine ,Anesthesiology and Pain Medicine ,business.industry ,medicine ,030212 general & internal medicine ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
Die Hypnose stellt ein sehr altes und effektives Heilverfahren dar. In den letzten Jahrzehnten war die moderne Hypnose vor allem eine Domane der Psychotherapie. Jedoch gewinnt die Hypnose als therapeutisches Verfahren in der Medizin wieder zunehmend an Bedeutung. Hypnose kann bei einer Vielzahl von medizinischen Indikationen eingesetzt werden. In der Literatur finden sich zahlreiche Beweise fur ihre Wirksamkeit. Ziel war es, die Effektivitat der Hypnose in der stationaren Therapie chronischer Schmerzpatienten aufzuzeigen und ein Selbsthypnoseprogramm darzustellen, welches gut in die Schmerztherapie integriert werden kann. Eingeschlossen wurden alle stationaren chronischen Schmerzpatienten von Oktober 2012 bis April 2013 (Gruppe 1: Nichthypnosegruppe; Gruppe 2: Hypnosegruppe). Fur die Gruppe 2 wurde ein Protokoll fur Hypnosetherapie zusatzlich zum standardisierten schmerztherapeutischen Programm integriert. Das Hauptziel der Hypnosetherapie war vor allem ein Selbsthypnosetraining, damit eine hausliche weitere Umsetzung gewahrleistet werden konnte. Mittels standardisierter Testverfahren (u. a. Gesundheitsfragebogen fur Patienten [PHQ-9], Pain Disability Index [PDI], Generalized Anxiety Disorder [GAD-7] und numerische Rating-Skalen [NRS] zum Schmerz und allgemeinen Wohlbefinden) wurden die Daten vor und nach der Schmerztherapie ausgewertet. Die pra- und poststationaren standardisierten Testverfahren von 30 chronischen Schmerzpatienten konnten ausgewertet werden (17 Patienten ohne Hypnose, 13 Patienten mit Hypnose). Die Hauptdiagnose nach ICD-10 war bei allen Patienten „chronische Schmerzerkrankung“ (F45.41) mit einem MPSS-Stadium III. Der PDI war in der Hypnosegruppe signifikant gebessert (p = 0,019). Die weiteren Items zeigten alle einen Trend zur Besserung in der Hypnosegruppe (Ausnahme GAD-7) ohne eine statistische Signifikanz (p > 0,05). Die vorliegende Arbeit konnte in einem ersten kleinen Patientenkollektiv zeigen, dass die Integration der modernen Hypnosetherapie in die Behandlung von chronischen Schmerzpatienten im stationaren Setting ein weiterer sinnvoller therapeutischer Aspekt sein kann. Insbesondere die Anleitung zum Erlernen selbststandig durchzufuhrender Hypnosetechniken erscheint aufgrund der begrenzten stationaren Zeit sinnvoll zu sein. Es bedarf weiterer Untersuchungen, um diese ersten Ergebnisse zu unterstutzen.
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- 2018
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36. The efficacy of pre-operative preparation with intravenous iron and/or erythropoietin in anaemic patients undergoing orthopaedic surgery
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Nikolaus Böhler, Axel Hofmann, Bettina Haslinger-Eisterer, Martina Heschl, Jens Meier, and Hans Gombotz
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Male ,medicine.medical_specialty ,Blood management ,Blood transfusion ,Anemia ,Iron ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Preoperative care ,03 medical and health sciences ,0302 clinical medicine ,030202 anesthesiology ,Internal medicine ,Preoperative Care ,Humans ,Medicine ,Blood Transfusion ,Orthopedic Procedures ,Erythropoietin ,Aged ,Aged, 80 and over ,business.industry ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Treatment Outcome ,Anesthesiology and Pain Medicine ,Orthopedic surgery ,Administration, Intravenous ,Female ,Observational study ,business ,medicine.drug - Abstract
BACKGROUND Pre-operative anaemia and transfusion are common among patients undergoing elective orthopaedic surgery. Application of 'patient blood management' might be the most effective way to reduce both anaemia and transfusion. Pre-operative administration of iron and/or erythropoietin (EPO) is one of the cornerstones of the first pillar of patient blood management, but in a daily clinical setting, efficacy and long-term safety of this measure have not been analysed thoroughly to date. OBJECTIVE To investigate the influence of pre-operative preparation (PREP) of patients with iron and/or EPO on peri-operative transfusion needs and long-term survival. DESIGN Single-centre, retrospective study. SETTING Anaesthesia department, University hospital. INTERVENTIONS Pre-operative preparation with iron and/or EPO versus no preparation. METHODS After approval of our local ethics committee, data of 5518 patients who received total hip or total knee replacement between 2008 and 2014 were included. Patients receiving iron and/or EPO were included in the PREP group, whereas patients without iron and/or EPO were included in the no preparation group. From the full data set, a bias-reduced subset of 662 patients was obtained by means of propensity score-matching to compare peri-operative red blood cell utilisation and long-term survival of patients between groups. RESULTS Patients in the PREP group needed a lower number of units of red blood cells than patients in the no preparation group (0.2 ± 0.8 vs. 0.5 ± 1.3, P
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- 2018
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37. Tearing energy and path-dependent J-integral evaluation considering stress softening for carbon black reinforced elastomers
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Mohammed El Yaagoubi, Jens Meier, Thomas Alshuth, Daniel Juhre, and Ulrich Giese
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Mullins effect ,Materials science ,Deformation (mechanics) ,Tension (physics) ,Cauchy stress tensor ,Mechanical Engineering ,Fracture mechanics ,02 engineering and technology ,Mechanics ,021001 nanoscience & nanotechnology ,Stress (mechanics) ,Condensed Matter::Materials Science ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Mechanics of Materials ,Tearing ,General Materials Science ,0210 nano-technology ,Softening - Abstract
For carbon black reinforced Ethylene-Propylene-Diene Monomer Rubber (EPDM) fracture mechanics investigations by using a Single Edge Notched Tension sample (SENT) are presented. Filled elastomers under cyclic loading typically display inelastic effects like permanent set, strong nonlinear S-shaped stress-strain behaviour and stress induced softening (discontinuous damage) as well as cyclic softening (continuous damage) better known as Mullins effect. These unique properties give this material class an interesting and a complex aspect regarding the experimental observations and numerical modelling of fracture mechanics. In simulations with homogenous material, the J-integral given as the evaluation of the Eshelby stress tensor along a path integral around the crack shows no dependency on the chosen integration path. In contrast, dissipative materials show strong path dependency of the J-integral. When the chosen path is near to the crack tip, this effect is pronounced, due to the inelastic effects, which are very high at the crack tip compared to the rest of the sample. In the process zone, the J-integral value depends strongly on the chosen path around the crack tip. This phenomenon occurs due to the intensity of inelastic effects near the crack tip. The path-dependency of J-integral using the variational formulation of a crack problem in a dissipative material has been given in [16]. Stumpf and Le have proposed a new formulation of the boundary value problem for elastoplastic cracked body using variational formulation, where the finite deformation was considered. For cyclic displacement controlled loading, the elastomers show typical stress softening behaviour, i.e. the force-displacement curve of each cycle is lower than the previous cycle and higher than the following cycle. This occurs due to the continuous damage, whereby the bondings between polymer chains and the filler particles are partially damaged. At small external amplitudes, the stress softening effect is significant only in the vicinity of the crack tip, because of the hysteresis which is large compared to the rest of the sample. The evaluation of the J-integral for an SENT sample under cyclic displacement controlled loading shows clearly that the resulting energy flux at the crack tip decreases from the virgin curve until the last repetition. The values found are in good agreement with experimentally evaluated tearing energy. Hence J-integral evaluation while considering a stress softening reflecting material model can be a promising approach used for estimation of the crack propagation or for lifetime prediction.
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- 2018
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38. Randomised controlled trials should be analysed using one-sided tests: PRO
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Thomas Tschoellitsch, Martin W. Dünser, Jens Meier, and Ulrich Bodenhofer
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medicine.medical_specialty ,Anesthesiology and Pain Medicine ,Text mining ,One sided ,business.industry ,Physical therapy ,Medicine ,General Medicine ,Critical Care and Intensive Care Medicine ,business - Published
- 2021
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39. ICU: Quick Drug Guide
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Jens Meier and Martin W. Dünser
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Drug ,medicine.medical_specialty ,Anesthesiology and Pain Medicine ,business.industry ,media_common.quotation_subject ,medicine ,Intensive care medicine ,business ,media_common - Published
- 2021
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40. RABBIT risk score and ICU admission due to infection in patients with rheumatoid arthritis
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Franz Gruber, Clemens Steinwender, Lorenz Auer-Hackenberg, Herwig Pieringer, Erich Pohanka, Rainer Hintenberger, and Jens Meier
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Male ,medicine.medical_specialty ,Infections ,law.invention ,Arthritis, Rheumatoid ,03 medical and health sciences ,0302 clinical medicine ,Rheumatology ,law ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Glucocorticoids ,Aged ,030203 arthritis & rheumatology ,Biological Products ,COPD ,Framingham Risk Score ,business.industry ,General Medicine ,Middle Aged ,medicine.disease ,Intensive care unit ,Surgery ,Icu admission ,Hospitalization ,Intensive Care Units ,Antirheumatic Agents ,Case-Control Studies ,Rheumatoid arthritis ,Female ,business ,Glucocorticoid ,medicine.drug ,Kidney disease - Abstract
Rheumatoid arthritis (RA) patients are at increased risk of infection. Aim of the present study was to investigate whether RA patients admitted to an intensive care unit (ICU) due to infection have higher Rheumatoid Arthritis Observation of Biologic Therapy (RABBIT) risk scores compared to control RA patients. Seventy-four RA patients (32.4% male) admitted to an ICU due to infection (from January 2002 to December 2013) and 74 frequency-matched control RA patients (16.2% male) were included in this cross-sectional study. There was strong evidence for a higher RABBIT risk score in ICU patients (median 2.0; IQR 1.3–3.2) as compared to controls (1.3; IQR 0.8–2.0; p
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- 2017
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41. Prediction of energy release rate in crack opening mode (mode I) for filled and unfilled elastomers using the Ogden model
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Daniel Juhre, Jens Meier, Ulrich Giese, Mohammed El Yaagoubi, and Thomas Alshuth
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Strain energy release rate ,Work (thermodynamics) ,Materials science ,Mullins effect ,Ogden ,Mechanical Engineering ,Fracture mechanics ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Stress (mechanics) ,Condensed Matter::Materials Science ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Mechanics of Materials ,Hyperelastic material ,Tearing ,General Materials Science ,Composite material ,0210 nano-technology - Abstract
A stretch intensity factor for filled and unfilled elastomers is introduced for different mixtures. This stretch intensity factor allows for prediction of the analytically evaluated energy release rate for a cracked sample under uniaxial tension. Considering the opening mode from fracture mechanics (mode I ) was investigated. The continuum mechanical derivations are based on non-linear hyperelastic material behaviour, where the energy release rate is evaluated through a closed path integral very near to the crack tip. Here, the integrand includes asymptotic solution for strain, stress and energy density using the Ogden model. The decisive advantage of this method is to predict well the critical tearing energy values by the crack growth using the analytical energy release rate term. In this work the Mullins effect is not considered, since the cracked samples are tested without any preconditioning.
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- 2017
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42. Vasopressor hormones in shock—noradrenaline, vasopressin or angiotensin II: which one will make the race?
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Martin W. Dünser and Jens Meier
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Vasopressin ,business.industry ,030208 emergency & critical care medicine ,Angiotensin II ,03 medical and health sciences ,Editorial ,0302 clinical medicine ,Endocrinology ,Internal medicine ,Shock (circulatory) ,medicine ,030212 general & internal medicine ,medicine.symptom ,business ,Hormone - Published
- 2017
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43. Differential Diagnosis of Alterations in Arterial Flow and Tissue Oxygenation on Venoarterial Extracorporeal Membrane Oxygenation
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Sylvia Leitner, Michaela Kreuzer, Jens Meier, and Anna Hofer
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Male ,Cardiac output ,medicine.medical_treatment ,Biomedical Engineering ,Medicine (miscellaneous) ,Blood Pressure ,Bioengineering ,030204 cardiovascular system & hematology ,Pericardial Effusion ,Diagnosis, Differential ,Biomaterials ,03 medical and health sciences ,Extracorporeal Membrane Oxygenation ,0302 clinical medicine ,Extracorporeal membrane oxygenation ,medicine ,Humans ,Cardiac Output ,Spectroscopy, Near-Infrared ,business.industry ,Infant, Newborn ,Pneumothorax ,030208 emergency & critical care medicine ,General Medicine ,Middle Aged ,Pulse pressure ,surgical procedures, operative ,Blood pressure ,Tissue oxygenation ,Arterial flow ,Anesthesia ,Differential diagnosis ,business - Abstract
Background Venoarterial extracorporeal membrane oxygenation (VA-ECMO) may be life-saving in several clinical situations, but it is also one of the most invasive therapeutic procedures, with significant potential for life-threatening complications. Pulse pressure waves are typically very small or even absent at the onset of ECMO therapy, and will reappear with the improvement of cardiac function. A low pulse pressure may indicate low cardiac output due to heart failure during sustained ECMO support. A sudden loss of pulse pressure during ECMO therapy, however, may reveal complications like pericardial tamponade, hemothorax or pneumothorax. Near infrared spectroscopy (NIRS) has been shown to be useful in detecting cerebral and lower limb ischemic events during ECMO therapy and could furthermore improve differential diagnosis in the event pulsatility of the arterial pressure trace is lost. Methods We are reporting on 3 different complications of ECMO and their impact on arterial pulse pressure, arterial oxygen tension and regional tissue oxygenation measured by NIRS. Results Pericardial hematoma, overinflation of the lung, and tension pneumothorax may impede cardiac output during VA-ECMO and cause a loss of pulse pressure. Monitoring of regional tissue oxygenation using NIRS, in addition to arterial and mixed venous oxygen tension, may allow early recognition and treatment of ECMO complications. Conclusions Together with the appearance of a flat, non pulsatile arterial pressure trace as well as a reduction in mixed venous oxygen saturation the improvement of upper body rSO2 measured by NIRS enables timely recognition of complications that interfere with natural cardiac output during VA-ECMO.
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- 2017
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44. Prediction of tearing energy in mode III for filled elastomers
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Thomas Alshuth, Mohammed El Yaagoubi, Daniel Juhre, Ulrich Giese, and Jens Meier
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Strain energy release rate ,Work (thermodynamics) ,Materials science ,business.industry ,Applied Mathematics ,Mechanical Engineering ,Energy flux ,02 engineering and technology ,Mechanics ,Structural engineering ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Crack growth resistance curve ,Condensed Matter::Materials Science ,Crack closure ,020303 mechanical engineering & transports ,Fracture toughness ,0203 mechanical engineering ,Hyperelastic material ,Tearing ,General Materials Science ,0210 nano-technology ,business - Abstract
Elastomers composites are viscoelastic materials and show a complex behaviour due to their non-linear response to external load, characterised in general by energy dissipation, residual set and material softening. For production reasons defects like micro-cracks and pores may be contained. A micro crack in a filled elastomer can occur between polymer-polymer, filler-polymer or filler-filler interfaces. Such a crack grows when the energy flux at the crack tip exceeds a critical value. Energy considerations at the crack shows that the energy released during the crack growth is not the total dissipated energy. The remaining energy is dissipated in the rest of the elastomer composite. In this study three different fracture criteria are compared: the tearing energy (Rivlin and Thomas, 1953), energy release rate (Gros and Seelig, 2011) and the J-integral (Rice, 1968). Tearing energy and energy release rate are based on the global energetic consideration and J-integral is based on the local energy observation. As a global criterion the tearing energy can be determined experimentally and numerically, whereas the J-integral is a local criterion at the crack tip and can be evaluated only numerically. The importance of local calculations lies in the determination of actually required tearing energy as well as the description of inelastic effects of elastomers at the crack tip. The analytical evaluation of the energy release rate allows for the prediction of the driving force at the crack tip without carrying out experiments for the determination of the tearing energy. Stumpf and Le (1990) have applied the variational principle to determine the energy flux at the mode I crack tip for a hyperelastic body. In this work only the trouser-sample is analysed. The load on this sample corresponds to the presented mode III from linear fracture mechanics. Here, the Ogden model is chosen (ABAQUS, 1998) as hyperelastic material model. The analytical determination of the energy release rate is calculated from the energy density function of this model. Results obtained from the experiments, simulations and analytical calculations are compared, where the analytical energy release rate turned out to be in closer accordance with the experimentally evaluated tearing energy than the J-Integral.
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- 2017
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45. Fatal case of COVID-19 in a 27-year-old woman with diabetes mellitus
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Christine Schlömmer, Martin W. Dünser, Christian Paar, Markus Winkler, Jens Meier, Marlies Antlanger, Helmut J F Salzer, and Bernd Lamprecht
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Pediatrics ,medicine.medical_specialty ,2019-20 coronavirus outbreak ,Fatal outcome ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Main Topic ,General Medicine ,medicine.disease ,Comorbidity ,Diabetes mellitus ,Medicine ,business - Published
- 2020
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46. Inflammatory response in trauma patients: are there ways to decrease the inflammatory reaction?
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Jens Meier and Christine Schlömmer
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0301 basic medicine ,Inflammation ,education.field_of_study ,medicine.medical_specialty ,Severe injury ,business.industry ,Inflammatory response ,Sterile inflammation ,Population ,Treatment options ,030208 emergency & critical care medicine ,medicine.disease ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Anesthesiology and Pain Medicine ,Immune system ,Coagulopathy ,Medicine ,Humans ,Wounds and Injuries ,In patient ,business ,education ,Intensive care medicine - Abstract
Purpose of review Trauma patients are considered a complex population of patients in emergency medicine and need extensive, specialized therapy. One major part is the prevention and treatment of the inflammatory response, which occurs in patients after severe injury resulting in complications like endotheliopathy. Likely as a consequence, coagulopathy occurs. Sterile inflammation is hard to address, especially because of the lack of a single activator. Moreover, it is a complex composition of factors that lead to a pathologic immune response. Our understanding of these patterns is increasing, but the complete pathophysiologic changes have yet to be investigated. Therefore, there is no specific target to treat inflammatory response in trauma patients at the moment. Recent findings There is increasing knowledge of the pathways and mediators that are responsible for the inflammatory response in patients after severe trauma. The endothelial glycocalyx has been identified to be an integral part of these mechanisms. There have been several new therapeutic approaches to diminish the inflammatory response. Summary Our increasing understanding of the immune system have led to new potential therapeutic perspectives. All of these approaches need further research to be validated. As the current therapies are based on empirical strategies and have not changed much over the years, new treatment options would be an important progress.
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- 2020
47. A Linear Parameter Varying ARX Model for Describing Biomedical Signal Couplings
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Peter Kovacs, Carl Bock, Mario Huemer, Jens Meier, and Kyriaki Kostoglou
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Coupling ,Computer science ,010401 analytical chemistry ,System identification ,computer.software_genre ,01 natural sciences ,Signal ,0104 chemical sciences ,03 medical and health sciences ,Information extraction ,Acceleration ,0302 clinical medicine ,Interference (communication) ,Autoregressive model ,Heart rate variability ,Biological system ,computer ,030217 neurology & neurosurgery - Abstract
Biomedical signal processing frequently deals with information extraction for clinical decision support. A major challenge in this field is to reveal diagnostic information by eliminating undesired interfering influences. In case of the electrocardiogram, e.g., a frequently arising interference is caused by respiration, which possibly superimposes diagnostic information. Respiratory sinus arrhythmia, i.e., the acceleration and deceleration of the heartrate (HR) during inhalation and exhalation, respectively, is a well-known phenomenon, which strongly influences the ECG. This influence becomes even more important, when investigating the so-called heart rate variability, a diagnostically powerful signal derived from the ECG. In this work, we propose a model for capturing the relationship between the HR and the respiration, thereby taking the time-variance of physiological systems into account. To this end, we show that so-called linear parameter varying autoregressive models with exogenous input are well suited for modeling the coupling between the two signals of interest.
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- 2020
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48. Influence of Filler Induced Cracks on the Statistical Lifetime of Rubber: A Review
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Marvin Ludwig, Jens Meier, Mohammed El Yaagoubi, and Stefan Robin
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Materials science ,Monte Carlo method ,Particle-size distribution ,Fracture mechanics ,Composite material ,Paris' law ,Deformation (engineering) ,Dispersion (chemistry) ,Finite element method ,Dynamic load testing - Abstract
A concept for the estimation of lifetime cycles is discussed assuming non-dispersed filler particles as origins of initial cracks which propagate under dynamic load according to fatigue crack growth (FCG) characteristics until failure occurs. Reference EPDM compounds with glass spheres of well defined size show strong correlation of the fatigue to failure analysis (FFA) behavior of dumbbells with largest incorporated particles, but dependence on polymer filler interaction, too. For NR and EPDM compounds, the occurrence of incorporated large particles is investigated by computed tomography and evaluated to a flaw size statistic. Based on the assumption of initial crack sizes matching the flaw diameters and together with the characteristic material parameters from FCG analysis, a statistical concept for the prediction of FFA lifetime analysis is presented. Predictions for near-homogeneously deforming dumbbell samples with carbon black (CB) reinforced NR display a particle size distribution which in combination with FCG results allows to calculate quantitative lifetime accordant to experimental findings, i.e. compounding dependency by shorter lifetime for worse dispersion and geometry dependency by longer lifetime for smaller specimens. An extension of the prediction concept for non-homogeneous deformation states is shown through a Monte Carlo simulation varying the positions of flaws inside the sample together with a Finite Element Analysis based calculation of the accordant local J-integral value. The simulations of lifetime statistics for rotational-parabolic buffer samples made of CB filled NR or EPDM show significant effects in average value and distribution width similarly found in experiment. This lifetime prediction concept has the unique capability to take into account not only recipe controlled matrix properties as cyclic crack propagation resistivity but volume dependency and processing related dispersion state, too in a quantitative manner.
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- 2020
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49. A Machine Learning-Based Triage Tool for Children With Acute Infection in a Low Resource Setting
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Pierre Mujyarugamba, Joseph C. Farmer, Lori Harmon, Niranjan Kissoon, Martin W. Dünser, Olivier Urayeneza, Arthur Kwizera, Andrew J. Patterson, Jens Meier, and Ndidiamaka Musa
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Male ,Adolescent ,Vital signs ,MEDLINE ,Developing country ,030204 cardiovascular system & hematology ,Critical Care and Intensive Care Medicine ,Machine learning ,computer.software_genre ,Infections ,Severity of Illness Index ,Machine Learning ,03 medical and health sciences ,0302 clinical medicine ,Sex Factors ,Severity of illness ,Post-hoc analysis ,Medicine ,Humans ,Hospital Mortality ,Prospective Studies ,Prospective cohort study ,Child ,Developing Countries ,business.industry ,Vital Signs ,Age Factors ,Rwanda ,Infant ,030208 emergency & critical care medicine ,Prognosis ,Triage ,Random forest ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Child Mortality ,Female ,Artificial intelligence ,business ,computer - Abstract
To deploy machine learning tools (random forests) to develop a model that reliably predicts hospital mortality in children with acute infections residing in low- and middle-income countries, using age and other variables collected at hospital admission.Post hoc analysis of a single-center, prospective, before-and-after feasibility trial.Rural district hospital in Rwanda, a low-income country in Sub-Sahara Africa.Infants and children greater than 28 days and less than 18 years of life hospitalized because of an acute infection.None.Age, vital signs (heart rate, respiratory rate, and temperature) capillary refill time, altered mental state collected at hospital admission, as well as survival status at hospital discharge were extracted from the trial database. This information was collected for 1,579 adult and pediatric patients admitted to a regional referral hospital with an acute infection in rural Rwanda. Nine-hundred forty-nine children were included in this analysis. We predicted survival in study subjects using random forests, a machine learning algorithm. Five prediction models, all including age plus two to five other variables, were tested. Three distinct optimization criteria of the algorithm were then compared. The in-hospital mortality was 1.5% (n = 14). All five models could predict in-hospital mortality with an area under the receiver operating characteristic curve ranging between 0.69 and 0.8. The model including age, respiratory rate, capillary refill time, altered mental state exhibited the highest predictive value area under the receiver operating characteristic curve 0.8 (95% CI, 0.78-0.8) with the lowest possible number of variables.A machine learning-based algorithm could reliably predict hospital mortality in a Sub-Sahara African population of 949 children with an acute infection using easily collected information at admission which includes age, respiratory rate, capillary refill time, and altered mental state. Future studies need to evaluate and strengthen this algorithm in larger pediatric populations, both in high- and low-/middle-income countries.
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- 2019
50. Machine learning-based prediction of transfusion
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Andreas Mitterecker, Karin Schwarzbauer, Thomas Tschoellitsch, Carl Bock, Adam Lloyd, Axel Hofmann, Jens Meier, Kevin M. Trentino, Michael F. Leahy, and Sepp Hochreiter
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Adult ,Male ,Blood transfusion ,medicine.medical_treatment ,Immunology ,030204 cardiovascular system & hematology ,Logistic regression ,Machine learning ,computer.software_genre ,Machine Learning ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,medicine ,Immunology and Allergy ,Humans ,Blood Transfusion ,Decision Making, Computer-Assisted ,Retrospective Studies ,Receiver operating characteristic ,business.industry ,Retrospective cohort study ,Hematology ,Western Australia ,Random forest ,Hospitalization ,Predictive value of tests ,Female ,Gradient boosting ,Artificial intelligence ,F1 score ,business ,computer ,Patient Blood Management ,030215 immunology - Abstract
Background The ability to predict transfusions arising during hospital admission might enable economized blood supply management and might furthermore increase patient safety by ensuring a sufficient stock of red blood cells (RBCs) for a specific patient. We therefore investigated the precision of four different machine learning–based prediction algorithms to predict transfusion, massive transfusion, and the number of transfusions in patients admitted to a hospital. Study Design and Methods This was a retrospective, observational study in three adult tertiary care hospitals in Western Australia between January 2008 and June 2017. Primary outcome measures for the classification tasks were the area under the curve for the receiver operating characteristics curve, the F1 score, and the average precision of the four machine learning algorithms used: neural networks (NNs), logistic regression (LR), random forests (RFs), and gradient boosting (GB) trees. Results Using our four predictive models, transfusion of at least 1 unit of RBCs could be predicted rather accurately (sensitivity for NN, LR, RF, and GB: 0.898, 0.894, 0.584, and 0.872, respectively; specificity: 0.958, 0.966, 0.964, 0.965). Using the four methods for prediction of massive transfusion was less successful (sensitivity for NN, LR, RF, and GB: 0.780, 0.721, 0.002, and 0.797, respectively; specificity: 0.994, 0.995, 0.993, 0.995). As a consequence, prediction of the total number of packed RBCs transfused was also rather inaccurate. Conclusion This study demonstrates that the necessity for intrahospital transfusion can be forecasted reliably, however the amount of RBC units transfused during a hospital stay is more difficult to predict.
- Published
- 2019
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