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2.
BMC Med Educ ; 24(1): 149, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38360743

ABSTRACT

INTRODUCTION: The global trend of legalizing medical cannabis (MC) is on the rise. In Germany, physicians have prescribed MC at the expense of health insurers since 2017. However, the teaching on MC has been scant in medical training. This study investigates medical students' attitudes and perceived competence regarding MC and evaluates how varying materials (videos/articles) impact their opinions. METHODS: Fourth-year medical students were invited to participate in the cross-sectional study. During an online session, students viewed a video featuring a patient with somatoform pain discussing her medical history, plus one of four randomly assigned MC-related materials (each an article and a video depicting a positive or negative perspective on MC). Students' opinions were measured at the beginning [T0] and the end of the course [T1] using a standardized questionnaire with a five-point Likert scale. We assessed the influence of the material on the students' opinions using paired-sample t-tests. One-way analysis of variance and Tukey post-hoc tests were conducted to compare the four groups. Pearson correlations assessed correlations. RESULTS: 150 students participated in the course, the response rate being 75.3% [T0] and 72.7% [T1]. At T0, students felt a little competent regarding MC therapy (M = 1.80 ± 0.82). At T1, students in groups 1 (positive video) and 3 (positive article) rated themselves as more capable in managing MC therapy [Formula: see text], and students in groups 3 (positive article) and 4 (negative article) felt more skilled in treating patients with chronic pain [Formula: see text]. Compared to the other groups, group 2 students (negative video) felt significantly less competent. They perceived cannabis as addictive, hazardous and unsuitable for medical prescription. DISCUSSION: This study showed that medical students lack knowledge and perceived competence in MC therapy. Material influences their opinions in different ways, and they seek more training on MC. This underlines that integrating MC education into medical curricula is crucial to address this knowledge gap.


Subject(s)
Education, Medical , Medical Marijuana , Students, Medical , Humans , Female , Medical Marijuana/therapeutic use , Cross-Sectional Studies , Attitude
3.
JMIR Med Educ ; 10: e53961, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38227363

ABSTRACT

BACKGROUND: Communication is a core competency of medical professionals and of utmost importance for patient safety. Although medical curricula emphasize communication training, traditional formats, such as real or simulated patient interactions, can present psychological stress and are limited in repetition. The recent emergence of large language models (LLMs), such as generative pretrained transformer (GPT), offers an opportunity to overcome these restrictions. OBJECTIVE: The aim of this study was to explore the feasibility of a GPT-driven chatbot to practice history taking, one of the core competencies of communication. METHODS: We developed an interactive chatbot interface using GPT-3.5 and a specific prompt including a chatbot-optimized illness script and a behavioral component. Following a mixed methods approach, we invited medical students to voluntarily practice history taking. To determine whether GPT provides suitable answers as a simulated patient, the conversations were recorded and analyzed using quantitative and qualitative approaches. We analyzed the extent to which the questions and answers aligned with the provided script, as well as the medical plausibility of the answers. Finally, the students filled out the Chatbot Usability Questionnaire (CUQ). RESULTS: A total of 28 students practiced with our chatbot (mean age 23.4, SD 2.9 years). We recorded a total of 826 question-answer pairs (QAPs), with a median of 27.5 QAPs per conversation and 94.7% (n=782) pertaining to history taking. When questions were explicitly covered by the script (n=502, 60.3%), the GPT-provided answers were mostly based on explicit script information (n=471, 94.4%). For questions not covered by the script (n=195, 23.4%), the GPT answers used 56.4% (n=110) fictitious information. Regarding plausibility, 842 (97.9%) of 860 QAPs were rated as plausible. Of the 14 (2.1%) implausible answers, GPT provided answers rated as socially desirable, leaving role identity, ignoring script information, illogical reasoning, and calculation error. Despite these results, the CUQ revealed an overall positive user experience (77/100 points). CONCLUSIONS: Our data showed that LLMs, such as GPT, can provide a simulated patient experience and yield a good user experience and a majority of plausible answers. Our analysis revealed that GPT-provided answers use either explicit script information or are based on available information, which can be understood as abductive reasoning. Although rare, the GPT-based chatbot provides implausible information in some instances, with the major tendency being socially desirable instead of medically plausible information.


Subject(s)
Communication , Students, Medical , Humans , Young Adult , Adult , Prospective Studies , Language , Medical History Taking
4.
J Med Internet Res ; 26: e52113, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38261378

ABSTRACT

BACKGROUND: Large language models such as GPT-4 (Generative Pre-trained Transformer 4) are being increasingly used in medicine and medical education. However, these models are prone to "hallucinations" (ie, outputs that seem convincing while being factually incorrect). It is currently unknown how these errors by large language models relate to the different cognitive levels defined in Bloom's taxonomy. OBJECTIVE: This study aims to explore how GPT-4 performs in terms of Bloom's taxonomy using psychosomatic medicine exam questions. METHODS: We used a large data set of psychosomatic medicine multiple-choice questions (N=307) with real-world results derived from medical school exams. GPT-4 answered the multiple-choice questions using 2 distinct prompt versions: detailed and short. The answers were analyzed using a quantitative approach and a qualitative approach. Focusing on incorrectly answered questions, we categorized reasoning errors according to the hierarchical framework of Bloom's taxonomy. RESULTS: GPT-4's performance in answering exam questions yielded a high success rate: 93% (284/307) for the detailed prompt and 91% (278/307) for the short prompt. Questions answered correctly by GPT-4 had a statistically significant higher difficulty than questions answered incorrectly (P=.002 for the detailed prompt and P<.001 for the short prompt). Independent of the prompt, GPT-4's lowest exam performance was 78.9% (15/19), thereby always surpassing the "pass" threshold. Our qualitative analysis of incorrect answers, based on Bloom's taxonomy, showed that errors were primarily in the "remember" (29/68) and "understand" (23/68) cognitive levels; specific issues arose in recalling details, understanding conceptual relationships, and adhering to standardized guidelines. CONCLUSIONS: GPT-4 demonstrated a remarkable success rate when confronted with psychosomatic medicine multiple-choice exam questions, aligning with previous findings. When evaluated through Bloom's taxonomy, our data revealed that GPT-4 occasionally ignored specific facts (remember), provided illogical reasoning (understand), or failed to apply concepts to a new situation (apply). These errors, which were confidently presented, could be attributed to inherent model biases and the tendency to generate outputs that maximize likelihood.


Subject(s)
Education, Medical , Medicine , Psychosomatic Medicine , Humans , Research Design
6.
J Med Internet Res ; 25: e43649, 2023 03 03.
Article in English | MEDLINE | ID: mdl-36867440

ABSTRACT

BACKGROUND: Virtual reality (VR)-based simulation is being increasingly used to train medical students in emergency medicine. However, because the usefulness of VR may depend on various factors, the best practices for implementing this technology in the medical school curriculum are yet to be determined. OBJECTIVE: The overall objective of our study was to assess the perceptions of a large cohort of students toward VR-based training and to identify the associations between these attitudes and individual factors, such as gender and age. METHODS: The authors implemented a voluntary, VR-based teaching session in the emergency medicine course at the Medical Faculty in Tübingen, Germany. Fourth-year medical students were invited to participate on a voluntary basis. Afterward, we asked the students about their perceptions, collected data on individual factors, and assessed the test scores achieved by them in the VR-based assessment scenarios. We used ordinal regression analysis and linear mixed-effects analysis to detect the impact of individual factors on the questionnaire answers. RESULTS: A total of 129 students participated in our study (mean age 24.7, SD 2.9 years; n=51, 39.8% male; n=77, 60.2% female). No student had previously used VR for learning, and only 4.7% (n=6) of the students had prior experience with VR. Most of the students agreed that VR can convey complex issues quickly (n=117, 91%), that VR is a useful addition to mannequin-based courses (n=114, 88%) or could even replace them (n=93, 72%), and that VR simulations should also be used for examinations (n=103, 80%). However, female students showed significantly less agreement with these statements. Most students perceived the VR scenario as realistic (n=69, 53%) and intuitive (n=62, 48%), with a relatively lower agreement for the latter among female respondents. We found high agreement among all participants (n=88, 69%) for immersion but strong disagreement (n=69, 54%) for empathy with the virtual patient. Only 3% (n=4) of the students felt confident regarding the medical content. Responses for the linguistic aspects of the scenario were largely mixed; however, most of the students were confident with the English language (not native) scenarios and disagreed that the scenario should be offered in their native language (female students agreed more strongly than male students). Most of the students would not have felt confident with the scenarios in a real-world context (n=69, 53%). Although physical symptoms during VR sessions were reported by 16% (n=21) of the respondents, this did not lead to the termination of the simulation. The regression analysis revealed that the final test scores were not influenced by gender, age, or prior experience in emergency medicine or with virtual reality. CONCLUSIONS: In this study, we observed a strong positive attitude in medical students toward VR-based teaching and assessment. However, this positivity was comparatively lower among female students, potentially indicating that gender differences need to be addressed when VR is implemented in the curriculum. Interestingly, gender, age, or prior experience did not influence the final test scores. Furthermore, confidence regarding the medical content was low, which suggests that the students may need further training in emergency medicine.


Subject(s)
Emergency Medicine , Students, Medical , Virtual Reality , Female , Male , Humans , Young Adult , Adult , Prospective Studies , Schools, Medical
7.
Transpl Int ; 34(10): 1959-1970, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34214208

ABSTRACT

Post-transplantation diabetes mellitus (PTDM) is a relevant complication following liver transplantation with profound impact on morbidity and mortality. To date, little is known about the evolution and dynamics of glucose metabolism and the impact of prediabetes in long-term follow-up. To address this issue, all consecutive adult liver transplant recipients (n = 429) from a European university hospital transplant center between 2007 and 2017 were analyzed retrospectively. In patients without pre-existing diabetes (n = 327), we conducted a longitudinal characterization of glucose metabolism. Median follow-up was 37 [9-64, IQR] months. Median prevalence of prediabetes was 39 [37-39]% and of PTDM 21 [17-22]%. Throughout follow-up, intra-individual glucose regulation of patients was highly variable, continuously fluctuating between different states of glucose metabolism (normal glucose tolerance, prediabetes, PTDM). Whereas overall survival and long-term kidney function of patients with PTDM were significantly lower than that of patients with normal glucose metabolism, prediabetes was not associated with adverse outcome. This study provides new insight into the dynamics and impact of glucose metabolism after liver transplantation. Unlike PTDM, prediabetes is not associated with adverse outcome, providing a window of opportunity for targeted intervention. The results underline the need for constant screening and intervention in posttransplant care of liver allograft recipients.


Subject(s)
Diabetes Mellitus , Kidney Transplantation , Liver Transplantation , Prediabetic State , Adult , Blood Glucose , Humans , Kidney , Kidney Transplantation/adverse effects , Postoperative Complications , Retrospective Studies , Risk Factors
8.
Clin Kidney J ; 14(6): 1691-1693, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34084465

ABSTRACT

Recurrence of primary focal segmental glomerulosclerosis (FSGS) occurs in up to 50% of patients after kidney transplantation and is associated with poor allograft outcome. Novel therapeutic concepts directly target podocyte function via B7-1 with inconsistent response. We present the case of a 19-year-old patient with recurrent primary FSGS early after living donor kidney transplantation. Plasmapheresis and rituximab did not induce remission. Repetitive abatacept administration was able to achieve partial remission. Maintenance immunosuppression was subsequently switched to a belatacept-based calcineurin inhibitor-free immunosuppression, resulting in sustained complete remission with excellent allograft function throughout a follow-up of >56 months.

10.
Dtsch Med Wochenschr ; 145(20): 1470-1475, 2020 Oct.
Article in German | MEDLINE | ID: mdl-33022728

ABSTRACT

Decisions about the initiation, continuation and termination of life-supporting treatments are a permanent challenge in intensive care units (ICUs). Decisions should be based on patient preferences and the medical indication. The medical indication is mainly the result of an assessment of the patient's prognosis and the applicable therapeutic options. Factors influencing the short term prognosis are mostly the severity of the acute leading disease, the number and severity of other organ failures and the response to initial treatment. Long term prognosis is dominated by the severity and number of comorbidities, age and the resulting frailty. Because in many patients all these informations are not available at the time of admission, in these cases a time-limited trial is often justified to gather all this information before a decision is made. These principles of decision making can also applied to situations in which ICU-capacities are limited (e. g. COVID-19 pandemic).


Subject(s)
Clinical Decision-Making , Critical Care , Betacoronavirus , COVID-19 , Coronavirus Infections , Humans , Intensive Care Units , Pandemics , Pneumonia, Viral , Prognosis , SARS-CoV-2
11.
PLoS One ; 15(3): e0230522, 2020.
Article in English | MEDLINE | ID: mdl-32214333

ABSTRACT

Chart review is an important tool to identify patient hazards. Most advanced medical students perform poorly during chart review but can learn how to identify patient hazards context-independently. Many hospitals have implemented electronic health records, which enhance patient safety but also pose challenges. We investigated whether electronic charts impair advanced medical students' recognition of patient hazards compared with traditional paper charts. Fifth-year medical students were randomized into two equal groups. Both groups attended a lecture on patient hazards and a training session on handling electronic health records. One group reviewed an electronic chart with 12 standardized patient hazards and then reviewed another case in a paper chart; the other group reviewed the charts in reverse order. The two case scenarios (diabetes and gastrointestinal bleeding) were used as the first and second case equally often. After each case, the students were briefed about the patient safety hazards. In total, 78.5% of the students handed in their notes for evaluation. Two blinded raters independently assessed the number of patient hazards addressed in the students' notes. For the diabetes case, the students identified a median of 4.0 hazards [25%-75% quantiles (Q25-Q75): 2.0-5.5] in the electronic chart and 5.0 hazards (Q25-Q75: 3.0-6.75) in the paper chart (equivalence testing, p = 0.005). For the gastrointestinal bleeding case, the students identified a median of 5.0 hazards (Q25-Q75: 4.0-6.0) in the electronic chart and 5.0 hazards (Q25-Q75: 3.0-6.0) in the paper chart (equivalence testing, p < 0.001). We detected no improvement between the first case [median 5.0 (Q25-Q75: 3.0-6.0)] and second case [median, 5.0 (Q25-Q75: 3.0-6.0); p < 0.001, test for equivalence]. Electronic charts do not seem to facilitate advanced medical students' recognition of patient hazards during chart review and may impair expertise formation.


Subject(s)
Electronic Health Records , Health Records, Personal , Patient Safety , Students, Medical , Adult , Diabetes Complications/complications , Diabetes Complications/diagnosis , Diabetes Mellitus/diagnosis , Education, Medical , Female , Gastrointestinal Hemorrhage/complications , Gastrointestinal Hemorrhage/diagnosis , Humans , Male , Recognition, Psychology , Young Adult
12.
Kidney Blood Press Res ; 44(6): 1383-1391, 2019.
Article in English | MEDLINE | ID: mdl-31618744

ABSTRACT

BACKGROUND: Unplanned start of renal replacement therapy is common in patients with end-stage renal disease and often accomplished by hemodialysis (HD) using a central venous catheter (CVC). Urgent start using peritoneal dialysis (PD) could be an alternative for some of the patients; however, this requires a hospital-based PD center that offers a structured urgent start PD (usPD) program. METHODS: In this prospective study, we describe the implementation of an usPD program at our university hospital by structuring the process from presentation to PD catheter implantation and start of PD within a few days. For clinical validation, we compared the patient flow before (2013-2015) and after (2016-2018) availability of usPD. RESULTS: In the 3 years before the availability of usPD, 14% (n = 12) of incident PD patients (n = 87) presented in an unplanned situation and were initially treated with HD using a CVC. In the 3 years after implementation of the usPD program, 18% (n = 18) of all incident PD patients (n = 103) presented in an unplanned situation of whom n = 12 (12%) were treated with usPD and n = 6 (6%) with initial HD. usPD significantly reduced the use of HD by 57% (p = 0.0005). Hospital stay was similar in patients treated with usPD (median 9 days) compared to those with elective PD (8 days), and significantly lower than in patients with initial HD (26 days, p = 0.0056). CONCLUSIONS: Implementation of an usPD program reduces HD catheter use and hospital stay in the unplanned situation.


Subject(s)
Central Venous Catheters , Kidney Failure, Chronic/therapy , Length of Stay , Peritoneal Dialysis/methods , Renal Dialysis , Catheterization/methods , Catheterization/standards , Female , Humans , Male , Middle Aged , Peritoneal Dialysis/standards , Prospective Studies , Renal Dialysis/instrumentation
13.
Kidney Blood Press Res ; 44(5): 984-992, 2019.
Article in English | MEDLINE | ID: mdl-31437852

ABSTRACT

BACKGROUND: Sodium-glucose cotransporter 2 (SGLT2) inhibition has been shown to reduce cardiovascular mortality and preserve kidney function in patients with type 2 diabetes. Kidney transplant recipients with diabetes demonstrate increased risk and accelerated progression of micro- and macrovascular complications and may specifically benefit from SGLT2 inhibition. However, potential concerns of SGLT2 inhibition include volume depletion and urinary tract infections. OBJECTIVES: We report data on the use of SGLT2 inhibitors in a case series of ten patients with diabetes after kidney transplantation in order to analyze efficacy, safety, and the effect on renal function. METHODS: Patients with a stable allograft function and no history of recurrent urinary tract infections were eligible. The SGLT2 inhibitor empagliflozin was given as add-on to preexisting antidiabetic treatment with initial dose reduction of the latter. RESULTS: Median estimated glomerular filtration rate at baseline was 57 mL/min/1.73 m2 and remained stable throughout the follow-up of 12.0 (5.3-12.0) months. Median HbA1c decreased from 7.3 to 7.1%. The rate of urinary tract infections and other side effects was low. CONCLUSIONS: SGLT2 inhibition is feasible and well tolerated in selected kidney transplant recipients with diabetes. Whether SGLT2 inhibition is able to reduce cardiovascular mortality and improve allograft survival in these patients has to be addressed in further studies.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Sodium-Glucose Transporter 2/therapeutic use , Aged , Humans , Kidney Transplantation , Middle Aged , Prospective Studies , Sodium-Glucose Transporter 2/pharmacology
14.
PLoS One ; 12(6): e0178794, 2017.
Article in English | MEDLINE | ID: mdl-28594858

ABSTRACT

INTRODUCTION: Early defibrillation is an important factor of survival in cardiac arrest. However, novice resuscitators often struggle with cardiac arrest patients. We investigated factors leading to delayed defibrillation performed by final-year medical students within a simulated bystander cardiac arrest situation. METHODS: Final-year medical students received a refresher lecture and basic life support training before being confronted with a simulated cardiac arrest situation in a simulation ambulance. The scenario was analyzed for factors leading to delayed defibrillation. We compared the time intervals the participants needed for various measures with a benchmark set by experienced resuscitators. After training, the participants were interviewed regarding challenges and thoughts during the scenario. RESULTS: The median time needed for defibrillation was 158 s (n = 49, interquartile range: 107-270 s), more than six-fold of the benchmark time. The major part of total defibrillation time (49%; median, n = 49) was between onset of ventricular fibrillation and beginning to prepare the defibrillator, more specifically the time between end of preparation of the defibrillator and actual delivery of the shock, with a mean proportion of 26% (n = 49, SD = 17%) of the overall time needed for defibrillation (maximum 67%). Self-reported reasons for this delay included uncertainty about the next step to take, as reported by 73% of the participants. A total of 35% were unsure about which algorithm to follow. Diagnosing the patient was subjectively difficult for 35% of the participants. Overall, 53% of the participants felt generally confused. CONCLUSIONS: Our study shows that novice resuscitators rarely achieve guideline-recommended defibrillation times. The most relative delays were observed when participants had to choose what to do next or which algorithm to follow, and thus i.e. performed extensive airway management before a life-saving defibrillation. Our data provides a first insight in the process of defibrillation delay and can be used to generate new hypotheses on how to provide a timely defibrillation.


Subject(s)
Cardiopulmonary Resuscitation/methods , Ventricular Fibrillation/therapy , Adult , Defibrillators , Female , Heart Arrest/therapy , Humans , Male , Prospective Studies
15.
BMC Emerg Med ; 17(1): 7, 2017 03 03.
Article in English | MEDLINE | ID: mdl-28253848

ABSTRACT

BACKGROUND: Chest compressions are a core element of cardio-pulmonary resuscitation. Despite periodic training, real-life chest compressions have been reported to be overly shallow and/or fast, very likely affecting patient outcomes. We investigated the effect of a brief Crew Resource Management (CRM) training program on the correction rate of improperly executed chest compressions in a simulated cardiac arrest scenario. METHODS: Final-year medical students (n = 57) were randomised to receive a 10-min computer-based CRM or a control training on ethics. Acting as team leaders, subjects performed resuscitation in a simulated cardiac arrest scenario before and after the training. Team members performed standardised overly shallow and fast chest compressions. We analysed how often the team leader recognised and corrected improper chest compressions, as well as communication and resuscitation quality. RESULTS: After the CRM training, team leaders corrected improper chest compressions (35.5%) significantly more often compared with those undergoing control training (7.7%, p = 0.03*). Consequently, four students have to be trained (number needed to treat = 3.6) for one improved chest compression scenario. Communication quality assessed by the Leader Behavior Description Questionnaire significantly increased in the intervention group by a mean of 4.5 compared with 2.0 (p = 0.01*) in the control group. CONCLUSION: A computer-based, 10-min CRM training improved the recognition of ineffective of chest compressions. Furthermore, communication quality increased. As guideline-adherent chest compressions have been linked to improved patient outcomes, our CRM training might represent a brief and affordable approach to increase chest compression quality and potentially improve patient outcomes.


Subject(s)
Cardiopulmonary Resuscitation/education , Crew Resource Management, Healthcare/methods , Education, Medical/methods , Emergency Medicine/education , Heart Arrest/therapy , Adult , Cardiopulmonary Resuscitation/methods , Cardiopulmonary Resuscitation/standards , Crew Resource Management, Healthcare/standards , Education, Medical/standards , Female , Germany , Humans , Male , Prospective Studies , Simulation Training/methods , Students, Medical
16.
J Nucl Med ; 58(5): 853-860, 2017 05.
Article in English | MEDLINE | ID: mdl-28183987

ABSTRACT

Hypoxia is essential for the development of autoimmune diseases such as rheumatoid arthritis (RA) and is associated with the expression of reactive oxygen species (ROS), because of the enhanced infiltration of immune cells. The aim of this study was to demonstrate the feasibility of measuring hypoxia noninvasively in vivo in arthritic ankles with PET/MRI using the hypoxia tracers 18F-fluoromisonidazole (18F-FMISO) and 18F-fluoroazomycinarabinoside (18F-FAZA). Additionally, we quantified the temporal dynamics of hypoxia and ROS stress using L-012, an ROS-sensitive chemiluminescence optical imaging probe, and analyzed the expression of hypoxia-inducible factors (HIFs). Methods: Mice underwent noninvasive in vivo PET/MRI to measure hypoxia or optical imaging to analyze ROS expression. Additionally, we performed ex vivo pimonidazole-/HIF-1α immunohistochemistry and HIF-1α/2α Western blot/messenger RNA analysis of inflamed and healthy ankles to confirm our in vivo results. Results: Mice diseased from experimental RA exhibited a 3-fold enhancement in hypoxia tracer uptake, even in the early disease stages, and a 45-fold elevation in ROS expression in inflamed ankles compared with the ankles of healthy controls. We further found strong correlations of our noninvasive in vivo hypoxia PET data with pimonidazole and expression of HIF-1α in arthritic ankles. The strongest hypoxia tracer uptake was observed as soon as day 3, whereas the most pronounced ROS stress was evident on day 6 after the onset of experimental RA, indicating that tissue hypoxia can precede ROS stress in RA. Conclusion: Collectively, for the first time to our knowledge, we have demonstrated that the noninvasive measurement of hypoxia in inflammation using 18F-FAZA and 18F-FMISO PET imaging represents a promising new tool for uncovering and monitoring rheumatic inflammation in vivo. Further, because hypoxic inflamed tissues are associated with the overexpression of HIFs, specific inhibition of HIFs might represent a new powerful treatment strategy.


Subject(s)
Arthritis, Rheumatoid/diagnostic imaging , Arthritis, Rheumatoid/immunology , Hypoxia-Inducible Factor 1/immunology , Misonidazole/analogs & derivatives , Nitroimidazoles/immunology , Positron-Emission Tomography/methods , Reactive Oxygen Species/immunology , Animals , Cell Hypoxia/immunology , Mice , Misonidazole/immunology , Molecular Imaging/methods , Radiopharmaceuticals/immunology , Reproducibility of Results , Sensitivity and Specificity , Severity of Illness Index , Up-Regulation/immunology
17.
PLoS One ; 10(4): e0124665, 2015.
Article in English | MEDLINE | ID: mdl-25902054

ABSTRACT

METHODS: CT26 colon carcinoma-bearing mice were anesthetized with isoflurane (IF) or ketamine/xylazine (KX) while breathing air or oxygen (O2). We performed 10 min static PET scans 1 h, 2 h and 3 h after [18F]FAZA injection and calculated the [18F]FAZA-uptake and tumor-to-muscle ratios (T/M). In another experimental group, we placed a pO2 probe in the tumor as well as in the gastrocnemius muscle to measure the pO2 and perfusion. RESULTS: Ketamine/xylazine-anesthetized mice yielded up to 3.5-fold higher T/M-ratios compared to their isoflurane-anesthetized littermates 1 h, 2 h and 3 h after [18F]FAZA injection regardless of whether the mice breathed air or oxygen (3 h, KX-air: 7.1 vs. IF-air: 1.8, p = 0.0001, KX-O2: 4.4 vs. IF-O2: 1.4, p < 0.0001). The enhanced T/M-ratios in ketamine/xylazine-anesthetized mice were mainly caused by an increased [18F]FAZA uptake in the carcinomas. Invasive pO2 probe measurements yielded enhanced intra-tumoral pO2 values in air- and oxygen-breathing ketamine/xylazine-anesthetized mice compared to isoflurane-anesthetized mice (KX-air: 1.01 mmHg, IF-air: 0.45 mmHg; KX-O2 9.73 mmHg, IF-O2: 6.25 mmHg). Muscle oxygenation was significantly higher in air-breathing isoflurane-anesthetized (56.9 mmHg) than in ketamine/xylazine-anesthetized mice (33.8 mmHg, p = 0.0003). CONCLUSION: [18F]FAZA tumor uptake was highest in ketamine/xylazine-anesthetized mice regardless of whether the mice breathed air or oxygen. The generally lower [18F]FAZA whole-body uptake in isoflurane-anesthetized mice could be due to the higher muscle pO2-values in these mice compared to ketamine/xylazine-anesthetized mice. When performing preclinical in vivo hypoxia PET studies, oxygen should be avoided, and ketamine/xylazine-anesthesia might alleviate the identification of tumor hypoxia areals.


Subject(s)
Anesthesia/adverse effects , Molecular Probes/metabolism , Muscles/diagnostic imaging , Neoplasms/diagnostic imaging , Nitroimidazoles/pharmacokinetics , Oxygen/metabolism , Positron-Emission Tomography , Animals , Blood Pressure/drug effects , Cell Line, Tumor , Female , Isoflurane/pharmacology , Ketamine/pharmacology , Mice, Inbred BALB C , Muscles/drug effects , Partial Pressure , Perfusion , Respiration/drug effects , Systole/drug effects , Xylazine/pharmacology
18.
BMC Med Educ ; 14: 185, 2014 Sep 06.
Article in English | MEDLINE | ID: mdl-25194168

ABSTRACT

BACKGROUND: Resuscitation is a life-saving measure usually instructed in simulation sessions. Small-group teaching is effective. However, feasible group sizes for resuscitation classes are unknown. We investigated the impact of different group sizes on the outcome of resuscitation training. METHODS: Medical students (n = 74) were randomized to courses with three, five or eight participants per tutor. The course duration was adjusted according to the group size, so that there was a time slot of 6 minutes hands-on time for every student. All participants performed an objective structured clinical examination before and after training. The teaching sessions were videotaped and resuscitation quality was scored using a checklist while we measured the chest compression parameters with a manikin. In addition, we recorded hands-on-time, questions to the tutor and unrelated conversation. RESULTS: Results are displayed as median (IQR). Checklist pass rates and scores were comparable between the groups of three, five and eight students per tutor in the post-test (93%, 100% and 100%). Groups of eight students asked fewer questions (0.5 (0.0 - 1.0) vs. 3.0 (2.0 - 4.0), p < .001), had less hands-on time (2:16 min (1:15 - 4:55 min) vs. 4:07 min (2:54 - 5:52 min), p = .02), conducted more unrelated conversations (17.0 ± 5.1 and 2.9 ± 1.7, p < 0.001) and had lower self-assessments than groups of three students per tutor (7.0 (6.1 - 9.0) and 8.2 (7.2 - 9.0), p = .03). CONCLUSIONS: Resuscitation checklist scores and pass rates after training were comparable in groups of three, five or eight medical students, although smaller groups had advantages in teaching interventions and hands-on time. Our results suggest that teaching BLS skills is effective in groups up to eight medical students, but smaller groups yielded more intense teaching conditions, which might be crucial for more complex skills or less advanced students.


Subject(s)
Cardiopulmonary Resuscitation/education , Education, Medical, Undergraduate , Education, Medical/methods , Group Processes , Group Structure , Adult , Checklist , Double-Blind Method , Feasibility Studies , Female , Germany , Humans , Male , Manikins , Prospective Studies
19.
PLoS One ; 9(2): e89198, 2014.
Article in English | MEDLINE | ID: mdl-24586591

ABSTRACT

BACKGROUND: Patient chart review is the gold standard for detection of potential patient hazards (i.e. medication errors or failure to follow up actionable results) in both routine clinical care and patient safety research. However, advanced medical students' ability to read patient charts and to identify patient hazards is rather poor. We therefore investigated whether it is possible to teach advanced medical students how to identify patient hazards independent of context (i.e. cancer versus cardiac failure) in patient charts. METHODS: All fifth-year medical students in one semester (n = 123) were randomized into two groups. One group (IC) received a patient chart review-training first and then a control-intervention and the other group (CI) received the control-intervention first and then the patient chart review-training. Before and after the teaching sessions, students reviewed different scenarios with standardized fictional patient charts containing 12 common patient hazards. Two blinded raters rated the students' notes for any patient hazard addressed in the notes using a checklist. The students were blinded to the study question and design. There was no external funding and no harm for the participating students. RESULTS: A total of 35 data sets had to be excluded because of missing data. Overall, the students identified 17% (IQR 8-29%) of the patient hazards before the training and 56% (IQR 41-66%) of the patient hazards after the training. At the second assessment students identified more patient hazards than at the first. They identified even more in the third. The effect was most pronounced after the patient chart review training (all p<.01). CONCLUSION: Patient chart review exercises and problem-based patient chart review training improve students' abilities to recognize patient hazards independent of context during patient chart review.


Subject(s)
Education, Medical/methods , Patient Care/methods , Patient Harm/prevention & control , Students, Medical , Adult , Cross-Over Studies , Female , Humans , Male
20.
Mol Imaging ; 12(5): 277-87, 2013.
Article in English | MEDLINE | ID: mdl-23759369

ABSTRACT

The aim of this study was to evaluate the impact of different anesthetics on 3'-[18F]fluoro-3'-deoxythymidine ([18F]FLT) uptake in carcinomas and arthritic ankles. To determine the amount of [18F]FLT uptake in subcutaneous CT26 colon carcinomas or arthritic ankles, spontaneously room air/medical air-breathing mice were anesthetized with isoflurane, a combination of medetomidine/midazolam, or ketamine/xylazine. Mice were kept conscious or anesthetized during [18F]FLT uptake before the 10-minute static positron emission tomographic (PET) investigations. [18F]FLT uptake in CT26 colon carcinomas and arthritic ankles was calculated by drawing regions of interest. We detected a significantly reduced (4.4 ± 0.9 %ID/cm3) [18F]FLT uptake in the carcinomas of ketamine/xylazine-anesthetized mice compared to the [18F]FLT-uptake in carcinomas of medetomidine/midazolam- (7.0 ± 1.5 %ID/cm3) or isoflurane-anesthetized mice (6.4 ± 1.5 %ID/cm3), whereas no significant differences were observed in arthritic ankles regardless of whether mice were anesthetized or conscious during tracer uptake. The time-activity curves of carcinomas and arthritic ankles yielded diverse [18F]FLT accumulation related to the used anesthetics. [18F]FLT uptake dynamics are different in arthritic ankles and carcinoma, and the magnitude and pharmacokinetics of [18F]FLT uptake are sensitive to anesthetics. Thus, for preclinical in vivo [18F]FLT PET studies in experimental tumor or inflammation models, we recommend the use of isoflurane anesthesia as it yields a stable tracer uptake and is easy to handle.


Subject(s)
Anesthetics/pharmacology , Dideoxynucleosides/pharmacology , Inflammation/diagnostic imaging , Neoplasms/diagnostic imaging , Animals , Dideoxynucleosides/administration & dosage , Dideoxynucleosides/pharmacokinetics , Disease Models, Animal , Female , Immunohistochemistry , Inflammation/pathology , Ki-67 Antigen/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Neoplasms/pathology , Radionuclide Imaging
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