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result(s) for
"Omlor, Albert J."
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Comparison of immersive and non-immersive virtual reality videos as substitute for in-hospital teaching during coronavirus lockdown: a survey with graduate medical students in Germany
by
Schwärzel, Leonie S.
,
Danziger, Guy
,
Sester, Urban
in
Clinical medicine
,
Clinical skills
,
College students
2022
As a consequence of the continued Covid-19 lockdown in Germany, in-hospital teaching for medical students was impossible. While lectures and other theoretical training were relatively easily converted into online sessions using platforms such as Moodle, Zoom and Microsoft Teams, this was not the case for practical skills and clinical interventions, such as bronchoscopy or colonoscopy. This study describes a workaround that was implemented at the Saarland University Hospital utilizing virtual reality equipment to convey the impressions of shadowing clinical procedures to the students without physical presence. To achieve this, 3D 180° videos of key clinical interventions of various internal medicine specialities were recorded, cut, and censored. The videos were uploaded to the e-learning YouTube channel of our institution and shared with the students via the private share function. The students could choose whether to use a VR-viewer to watch the videos immersively or to watch them without a viewer on a screen non-immersively. At the end of the course after 1 week, the students completed a questionnaire anonymously focusing on learning-success regarding the presented topics, a self-assessment, and an evaluation of the course. A total of 27 students watched the videos with a VR-Viewer and 74 watched non-immersively. Although the VR-viewer group self-assessed their expertise higher, there was no significant difference between the two groups in the learning-success test score. However, students in the VR-viewer group rated the learning atmosphere, comprehensibility, and overall recommendation of the course significantly higher. They also agreed significantly more to the statement, that they gained a better conception of the presented procedures, and that virtual reality might be an appropriate tool for online teaching. Video-assisted teaching facilitates learning and might be a valuable add-on to conventional teaching.
Abbreviations: Covid-19: severe acute respiratory syndrome coronavirus 2; 3D: three-dimensional; 2D: Two-dimensional; VR: virtual reality
Journal Article
Comparison of Serial and Parallel Connections of Membrane Lungs against Refractory Hypoxemia in a Mock Circuit
2023
Extracorporeal membrane oxygenation (ECMO) is an important rescue therapy method for the treatment of severe hypoxic lung injury. In some cases, oxygen saturation and oxygen partial pressure in the arterial blood are low despite ECMO therapy. There are case reports in which patients with such instances of refractory hypoxemia received a second membrane lung, either in series or in parallel, to overcome the hypoxemia. It remains unclear whether the parallel or serial connection is more effective. Therefore, we used an improved version of our full-flow ECMO mock circuit to test this. The measurements were performed under conditions in which the membrane lungs were unable to completely oxygenate the blood. As a result, only the photometric pre- and post-oxygenator saturations, blood flow and hemoglobin concentration were required for the calculation of oxygen transfer rates. The results showed that for a pre-oxygenator saturation of 45% and a total blood flow of 10 L/min, the serial connection of two identical 5 L rated oxygenators is 17% more effective in terms of oxygen transfer than the parallel connection. Although the idea of using a second membrane lung if refractory hypoxia occurs is intriguing from a physiological point of view, due to the invasiveness of the solution, further investigations are needed before this should be used in a wider clinical setting.
Journal Article
A Novel Mock Circuit to Test Full-Flow Extracorporeal Membrane Oxygenation
2022
Extracorporeal membrane oxygenation (ECMO) has become an important therapeutic approach in the COVID-19 pandemic. The development and research in this field strongly relies on animal models; however, efforts are being made to find alternatives. In this work, we present a new mock circuit for ECMO that allows measurements of the oxygen transfer rate of a membrane lung at full ECMO blood flow. The mock utilizes a large reservoir of heparinized porcine blood to measure the oxygen transfer rate of the membrane lung in a single passage. The oxygen transfer rate is calculated from blood flow, hemoglobin value, venous saturation, and post-membrane arterial oxygen pressure. Before the next measuring sequence, the blood is regenerated to a venous condition with a sweep gas of nitrogen and carbon dioxide. The presented mock was applied to investigate the effect of a recirculation loop on the oxygen transfer rate of an ECMO setup. The recirculation loop caused a significant increase in post-membrane arterial oxygen pressure (paO2). The effect was strongest for the highest recirculation flow. This was attributed to a smaller boundary layer on gas fibers due to the increased blood velocity. However, the increase in paO2 did not translate to significant increases in the oxygen transfer rate because of the minor significance of physically dissolved oxygen for gas transfer. In conclusion, our results regarding a new ECMO mock setup demonstrate that recirculation loops can improve ECMO performance, but not enough to be clinically relevant.
Journal Article
Comparison of Circular and Parallel-Plated Membrane Lungs for Extracorporeal Carbon Dioxide Elimination
by
Schwärzel, Leonie S.
,
Muellenbach, Ralf M.
,
Dinh, Quoc Thai
in
ARDS
,
Blood flow
,
Carbon dioxide
2021
Extracorporeal carbon dioxide removal (ECCO2R) is an important technique to treat critical lung diseases such as exacerbated chronic obstructive pulmonary disease (COPD) and mild or moderate acute respiratory distress syndrome (ARDS). This study applies our previously presented ECCO2R mock circuit to compare the CO2 removal capacity of circular versus parallel-plated membrane lungs at different sweep gas flow rates (0.5, 2, 4, 6 L/min) and blood flow rates (0.3 L/min, 0.9 L/min). For both designs, two low-flow polypropylene membrane lungs (Medos Hilte 1000, Quadrox-i Neonatal) and two mid-flow polymethylpentene membrane lungs (Novalung Minilung, Quadrox-iD Pediatric) were compared. While the parallel-plated Quadrox-iD Pediatric achieved the overall highest CO2 removal rates under medium and high sweep gas flow rates, the two circular membrane lungs performed relatively better at the lowest gas flow rate of 0.5 L/min. The low-flow Hilite 1000, although overall better than the Quadrox i-Neonatal, had the most significant advantage at a gas flow of 0.5 L/min. Moreover, the circular Minilung, despite being significantly less efficient than the Quadrox-iD Pediatric at medium and high sweep gas flow rates, did not show a significantly worse CO2 removal rate at a gas flow of 0.5 L/min but rather a slight advantage. We suggest that circular membrane lungs have an advantage at low sweep gas flow rates due to reduced shunting as a result of their fiber orientation. Efficiency for such low gas flow scenarios might be relevant for possible future portable ECCO2R devices.
Journal Article
A mock circulation loop to test extracorporeal CO2 elimination setups
by
Schwärzel, Leonie S
,
Muellenbach, Ralf M
,
Schenk, Joachim
in
Acidification
,
Animal research
,
Blood
2020
BackgroundExtracorporeal carbon dioxide removal (ECCO2R) is a promising yet limited researched therapy for hypercapnic respiratory failure in acute respiratory distress syndrome and exacerbated chronic obstructive pulmonary disease. Herein, we describe a new mock circuit that enables experimental ECCO2R research without animal models. In a second step, we use this model to investigate three experimental scenarios of ECCO2R: (I) the influence of hemoglobin concentration on CO2 removal. (II) a potentially portable ECCO2R that uses air instead of oxygen, (III) a low-flow ECCO2R that achieves effective CO2 clearance by recirculation and acidification of the limited blood volume of a small dual lumen cannula (such as a dialysis catheter).ResultsWith the presented ECCO2R mock, CO2 removal rates comparable to previous studies were obtained. The mock works with either fresh porcine blood or diluted expired human packed red blood cells. However, fresh porcine blood was preferred because of better handling and availability. In the second step of this work, hemoglobin concentration was identified as an important factor for CO2 removal. In the second scenario, an air-driven ECCO2R setup showed only a slightly lower CO2 wash-out than the same setup with pure oxygen as sweep gas. In the last scenario, the low-flow ECCO2R, the blood flow at the test membrane lung was successfully raised with a recirculation channel without the need to increase cannula flow. Low recirculation ratios resulted in increased efficiency, while high recirculation ratios caused slightly reduced CO2 removal rates. Acidification of the CO2 depleted blood in the recirculation channel caused an increase in CO2 removal rate.ConclusionsWe demonstrate a simple and cost effective, yet powerful, “in-vitro” ECCO2R model that can be used as an alternative to animal experiments for many research scenarios. Moreover, in our approach parameters such as hemoglobin level can be modified more easily than in animal models.
Journal Article
Time-updated resting heart rate predicts mortality in patients with COPD
by
Stefan, Andreas
,
Alter, Peter
,
Biertz, Frank
in
Cardiovascular diseases
,
Chronic obstructive pulmonary disease
,
Clinical trials
2020
High resting heart rate (RHR) is associated with higher mortality in the general population and in cardiovascular disease. Less is known about the association of RHR with outcome in chronic obstructive pulmonary disease (COPD). In particular, the time-updated RHR (most recent value before the event) appears informative. This is the first study to investigate the association of time-updated RHR with mortality in COPD. We compared the baseline and time-updated RHR related to survival in 2218 COPD patients of the German COSYCONET cohort (COPD and Systemic Consequences—Comorbidities Network). Patients with a baseline RHR > 72 beats per minute (bmp) had a significantly (p = 0.049) higher all-cause mortality risk (adjusted hazard ratio (HR) of 1.37 (1.00–1.87) compared to baseline RHR ≤ 72 bpm. The time-updated RHR > 72 bpm was markedly superior (HR 1.79, 1.30–2.46, p = 0.001). Both, increased baseline and time-updated RHR, were independently associated with low FEV1, low TLCO, a history of diabetes, and medication with short-acting beta agonists (SABAs). In conclusion, increased time-updated RHR is associated with higher mortality in COPD independent of other predictors and superior to baseline RHR. Increased RHR is linked to lung function, comorbidities and medication. Whether RHR is an effective treatment target in COPD, needs to be proven in controlled trials.
Journal Article
A smoking prevention photoageing intervention for secondary schools in Brazil delivered by medical students: protocol for a randomised trial
by
Fries, Fabian N
,
Oliveira, Ana Carla Cruz
,
Faria, Bianca Lisa
in
Addictive behaviors
,
Adolescent
,
Aging
2017
IntroductionMost smokers start smoking during their early adolescence, often with the idea that smoking is glamorous; the dramatic health consequences are too far in the future to fathom. We recently designed and tested an intervention that takes advantage of the broad availability of mobile phones as well as adolescents’ interest in their appearance. A free photoageing mobile app (Smokerface) was implemented by medical students in secondary schools via a novel method called mirroring. The pupils’ altered three-dimensional selfies on tablets were ‘mirrored’ via a projector in front of their whole grade. This is the first randomised trial to measure the effectiveness of the mirroring approach on smoking behaviour in secondary schools.Methods and analysisThe mirroring intervention, which lasts 45 min, is implemented by Brazilian medical students in at least 35 secondary school classes with 21 participants each (at least 35 classes with 21 participants for control) in February 2018 in the city of Itauna, Brazil. External block randomisation via computer is performed on the class level with a 1:1 allocation. In addition to sociodemographic data, smoking behaviour is measured via a paper–pencil questionnaire before, 3 and 6 months postintervention plus a random carbon monoxide breathing test at baseline and end line. The primary outcome is cigarette smoking in the past week at 6 months follow-up. Smoking behaviour (smoking onset, quitting) and effects on the different genders are studied as secondary outcomes. Analysis is by intention to treat.Ethics and disseminationEthical approval is obtained from the ethics committee of the University of Itauna in Brazil. Results will be disseminated at conferences, in peer-reviewed journals, throughout the Education Against Tobacco network social media channels and on our websites.Trial registration number NCT03178227.
Journal Article
Facial-Aging Mobile Apps for Smoking Prevention in Secondary Schools in Brazil: Appearance-Focused Interventional Study
by
Berking, Carola
,
Corrêa, Paulo César Rodrigues Pinto
,
Brinker, Titus Josef
in
Adolescents
,
Aging
,
Behavior
2018
Most smokers start smoking during their early adolescence, often with the idea that smoking is glamorous. Interventions that harness the broad availability of mobile phones as well as adolescents' interest in their appearance may be a novel way to improve school-based prevention. A recent study conducted in Germany showed promising results. However, the transfer to other cultural contexts, effects on different genders, and implementability remains unknown.
In this observational study, we aimed to test the perception and implementability of facial-aging apps to prevent smoking in secondary schools in Brazil in accordance with the theory of planned behavior and with respect to different genders.
We used a free facial-aging mobile phone app (\"Smokerface\") in three Brazilian secondary schools via a novel method called mirroring. The students' altered three-dimensional selfies on mobile phones or tablets and images were \"mirrored\" via a projector in front of their whole grade. Using an anonymous questionnaire, we then measured on a 5-point Likert scale the perceptions of the intervention among 306 Brazilian secondary school students of both genders in the seventh grade (average age 12.97 years). A second questionnaire captured perceptions of medical students who conducted the intervention and its conduction per protocol.
The majority of students perceived the intervention as fun (304/306, 99.3%), claimed the intervention motivated them not to smoke (289/306, 94.4%), and stated that they learned new benefits of not smoking (300/306, 98.0%). Only a minority of students disagreed or fully disagreed that they learned new benefits of nonsmoking (4/306, 1.3%) or that they themselves were motivated not to smoke (5/306, 1.6%). All of the protocol was delivered by volunteer medical students.
Our data indicate the potential for facial-aging interventions to reduce smoking prevalence in Brazilian secondary schools in accordance with the theory of planned behavior. Volunteer medical students enjoyed the intervention and are capable of complete implementation per protocol.
Journal Article
A Dermatologist's Ammunition in the War Against Smoking: A Photoaging App
by
Seeger, Werner
,
Karoglan, Ante
,
Petri, Maximilian Philip
in
Aging
,
Ammunition
,
Child development
2017
This viewpoint reviews the perspectives for dermatology as a specialty to go beyond the substantial impact of smoking on skin disease and leverage the impact of skin changes on a person's self-concept and behavior in the design of effective interventions for smoking prevention and cessation.
Journal Article