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Aortic dissection is caused by a tear on the aortic wall that allows blood to flow through the wall layers. Usually, this tear involves the intimal and partly the medial layer of the aortic wall. As a result, a new false lumen develops besides the original aorta, denoted then as the true lumen. The local hemodynamic conditions such as flow disturbances, recirculations and low wall shear stress may cause thrombus formation and growth in the false lumen. Since the false lumen status is a significant predictor for late‐dissection‐related deaths, it is of great importance in the medical management of patients with aortic dissection. The hemodynamic changes in the aorta also alter the electrical conductivity of blood. Since the blood is much more conductive than other tissues in the body, such changes can be identified with non‐invasive methods such as impedance cardiography. Therefore, in this study, the capability of impedance cardiography in monitoring thrombosis in the false lumen is studied by multiphysics simulations to assist clinicians in the medical management of patients under treatment. To tackle this problem, a 3D computational fluid dynamics simulation has been set up to model thrombosis in the false lumen and its impact on the blood flow‐induced conductivity changes. The electrical conductivity changes of blood have been assigned as material properties of the blood‐filled aorta in a 3D finite element electric simulation model to investigate the impact of conductivity changes on the measured impedance from the body's surface. The results show remarkable changes in the electrical conductivity distribution in the measurement region due to thrombosis in the false lumen, which significantly impacts the morphology of the impedance cardiogram. Thus, frequent monitoring of impedance cardiography signals may allow tracking the thrombus formation and growth in the false lumen. [ABSTRACT FROM AUTHOR]

Computational hemodynamics has received increasing attention recently. Patient-specific simulations require questionable model assumptions, for example, for geometry, boundary conditions, and material parameters. Consequently, the credibility of these simulations is much doubted, and rightly so. Yet, the matter may be addressed by a rigorous uncertainty quantification. In this contribution, we investigated the impact of blood rheological models on wall shear stress uncertainties in aortic hemodynamics obtained in numerical simulations. Based on shear-rheometric experiments, we compare the non-Newtonian Carreau model to a simple Newtonian model and a Reynolds number-equivalent Newtonian model. Bayesian Probability Theory treats uncertainties consistently and allows to include elusive assumptions such as the comparability of flow regimes. We overcome the prohibitively high computational cost for the simulation with a surrogate model, and account for the uncertainties of the surrogate model itself, too. We have two main findings: (1) The Newtonian models mostly underestimate the uncertainties as compared to the non-Newtonian model. (2) The wall shear stresses of specific persons cannot be distinguished due to largely overlapping uncertainty bands, implying that a more precise determination of person-specific blood rheological properties is necessary for person-specific simulations. While we refrain from a general recommendation for one rheological model, we have quantified the error of the uncertainty quantification associated with these modeling choices., (© 2022 The Authors. International Journal for Numerical Methods in Biomedical Engineering published by John Wiley & Sons Ltd.)

Objective: To investigate the efficacy of blended learning (BL) in emergency medical resident education related to the diagnosis and treatment of benign paroxysmal positional vertigo., Study Design: A mixed-method study., Place and Duration of Study: Emergency Department of Hamad General Hospital, Doha, Qatar from 1st to 31st January 2018., Methodology: Participating emergency medical residents were assigned to either traditional lecturing (TL) or BL groups and they used several instruments to review medical knowledge and skills before and after instruction. The residents' opinions were sought through semi-structured interviews., Results: Students in both groups possessed similar knowledge and skills improvement, but reported a strong preference for TL., Conclusion: There is a need for further evaluation of learning technology and students' learning styles to maximise medical education.

Introduction: For the treatment of anxiety disorders behavior therapy-oriented methods are recommended for primary care as well. Within the trial "Jena-PARADISE" a primary care practice team-supported exposure training for patients with panic disorder with or without agoraphobia was developed and evaluated. The present paper gives an overview of general practitioners' subjective views on the practicability, feasibility and effectiveness of this new intervention for both patients and GP teams., Methods: Questions were operationalized based on Bellg's intervention fidelity framework. Fourteen GPs of the intervention group were sampled purposefully and interviewed in a semi-structured way. Generated data were analyzed following Mayring's content analysis approach., Results: The treatment program was positively assessed among the GPs and seen as a useful therapeutic option for inadequately treated patients. The therapy elements 'psycho-education' and 'interoceptive exposure exercises' were described as feasible, while situational exercises and relapse prevention got a less positive rating. The active participation of the nurse in the treatment program was seen as supportive., Conclusion: From the GP perspective, the treatment program for patients with panic disorder and/or agoraphobia seems to be a viable therapeutic option in primary care., (Copyright © 2019. Published by Elsevier GmbH.)

Background: Behavior therapy-oriented methods are recommended for treating anxiety disorders in primary care. The treatment of patients with long-term conditions can be improved by case management and structured clinical monitoring. The present paper describes the rationale, design and application of the 'Jena Anxiety Monitoring List' (JAMoL), a monitoring tool for the treatment of patients with panic disorder, with or without agoraphobia, in primary care., Methods: JAMoL's design was based on established clinical measures, the rationale of exposure-based anxiety treatment, and research on family practice-based case management. After piloting, the JAMoL was used in the clinical study 'Jena-PARADISE' (ISRCTN64669297), where non-physician practice staff monitored patients with panic disorder by telephone. Using semi-structured interviews in concomitant studies, study participants were asked about the instrument's functionality., Results: The JAMoL assesses the severity of anxiety symptoms (6 items) as well as the patient's adherence to therapy (4 items) and fosters the case management-related information exchange (3 items). An integrated traffic light scheme facilitates the evaluation of monitoring results. Within the clinical study, non-physician practice staff carried out a total of 1,525 JAMoL-supported monitoring calls on 177 patients from 30 primary care practices (median calls per patient: 10 [interquartile range, 9-10]). Qualitative analyses revealed that most practice teams and patients rated the JAMoL as a practicable and treatment-relevant tool., Conclusions: The JAMoL enables primary care practice teams to continuously monitor anxiety symptoms and treatment adherence in patients with panic disorder with or without agoraphobia. Within the behavior therapy-oriented treatment program 'Jena-PARADISE', the JAMoL constitutes an important case management tool., (Copyright © 2018. Published by Elsevier GmbH.)