Juan Cendan

The use of virtual patients in medical school curricula

The demonstration of patient-based cases using automated technology [virtual patients (VPs)] has been available to health science educators for a number of decades. Despite the promise of VPs as an easily accessible and moldable platform, their widespread acceptance and integration into medical curricula have been slow. Here, the authors review the technological underpinnings of VPs, summarize the literature regarding the use and limitations of VPs in the healthcare curriculum, describe novel possible applications of the technology, and propose possible directions for future work.

Sentinel Lymph Node Biopsy for Ductal Carcinoma in Situ: An Evolving Approach at the University of Florida

Abstract:  While sentinel lymph node biopsy (SLNB) has virtually replaced axillary dissection as the initial diagnostic procedure for invasive breast cancer, the role of SLNB in ductal carcinoma in situ (DCIS) remains controversial. The purpose of this study was to review our experience with SLNB in DCIS. All patients with DCIS or DCIS with microinvasion (DCISM) who underwent SLNB from June 1997 to April 2002 at the University of Florida were included for analysis. The indications for SLNB were at the discretion of the treating surgeon. Lymphatic mapping involved a sequential dermal‐peritumoral radiocolloid injection and dynamic lymphoscintigraphy followed by an intraoperative assessment of radioactivity with a handheld gamma probe. All sentinel lymph nodes (SLNs) with radioactive counts ≥10% of the ex vivo counts of the most radioactive SLN were removed. Pathologic analysis consisted of slicing the SLN at 2 mm intervals for permanent section. All paraffin blocks of the SLNs were step sectioned in 4 µm sections (92 µm spacing) through the entire lymph node. Slides were then stained with an immunohistochemical stain for cytokeratin (AE1/AE3) and evaluated by microscopy. Nodal metastases were classified using the 6th edition of the American Joint Committee on Cancer (AJCC) staging manual. From April 1998 to April 2002, 43 patients with DCIS underwent SLNB at the University of Florida. Seven patients (16%) with multifocal or extensive DCIS (five patients) or DCISM (two patients) who underwent SLNB had a positive sentinel node. Two of the three patients considered positive by immunohistochemistry alone had either DCISM or invasive disease. Four (80%) of the five patients with extensive DCIS and a positive sentinel node were ultimately determined to have invasive or microinvasive disease. While SLNB remains controversial in DCIS, our data suggest that patients with extensive DCIS should undergo SLNB at the initial procedure to avoid the need for a second operation. Data from clinical trials are needed to determine the impact of SLNB results on overall survival in patients with DCIS.

Changing the Student Clerkship from Traditional Lectures to Small Group Case-Based Sessions Benefits the Student and The Faculty

BACKGROUND Attempts to improve the third year surgery clerkship led to the implementation of faculty-led small group teaching instead of large group lecture-style dissemination of the general surgical curriculum. The intent was to facilitate better faculty-to-student relationships, provide more favorable balance between classroom and clinical surgery, and enhance overall surgical education. METHODS Didactic student sessions were reduced from 33 lectures to 8 small group sessions and surgical specialty lectures. A case-based surgical curriculum was utilized and students were organized into small groups led by assigned faculty members. A uniform schedule of topics was prearranged to ensure continuity and avoid duplication of material. The National Board of Medical Examiners (NBME) surgery subject examination raw score and percentile rank assignments were analyzed for 1 medical graduating class taught using the traditional method and compared with the subsequent class taught in small groups. A survey was administered to assess student and faculty regarding the new format. RESULTS Average NBME percentile rank score for students educated in small groups versus lecture-only groups improved significantly (61.2 vs 55.9, p = 0.04, Student t test). The students reported increased time spent preparing for small group over lecture and more satisfaction with the small group teaching environment. Faculty members reported an increase in time needed to deliver the session but otherwise gave strong positive feedback. CONCLUSIONS Concerns that student performance on standardized testing would suffer from the proposed change were not substantiated as performance on NBME subject examinations actually improved. Additional preparation time, method preference, favorable balance of classroom to clinical exposure, and direct interactions with faculty may be responsible for the observed increase in NBME examination percentile scores. Faculty members were overwhelmingly in favor of the new model and the additional direct contact with students may prove beneficial in junior faculty promotion and career development.

Obese patients show a depressed cytokine profile following severe blunt injury.

ABSTRACT We hypothesized that severely injured obese patients would display increased concentrations of proinflammatory cytokines when compared with patients of normal body mass index (BMI) and that this would be associated with multiple organ failure (MOF). This was a retrospective review of prospectively collected data in the “Inflammation and the Host Response to Injury” trauma-related database. Data were collected prospectively from US level I trauma centers. The subjects were severely injured adult blunt trauma patients. Cytokine concentrations obtained within 12 h of injury and on days 1 and 4 were compared between subjects on the basis of BMI (normal, 18.5–24.9 kg/m2, and obese, ≥30 kg/m2). Demographic measures, injury severity, cytokine concentrations, and outcome measures were compared between groups. Seventy-four adult blunt trauma victims were evaluated. Relative to patients of normal BMI (n = 34), obese patients (n = 40) demonstrated an overall depressed cytokine response to severe injury, with significantly lower concentrations of several cytokines. Obese patients showed greater incidences of nosocomial infection (60 vs. 45%, not statistically significant) and MOF (63% vs. 44%, not statistically significant) and a later onset of maximum MOF score (5 vs. 3 days, P < 0.04) when compared with those of normal BMI. Despite prior reports suggesting a proinflammatory cytokine profile in obese individuals, obese patients sustaining severe injury show a depressed early cytokine response when compared with patients of normal BMI. This may confer increased susceptibility to nosocomial infection and later MOF. Further study of immune dysfunction in the postinjury obese patient should assess the possibility of early immune suppression.

Enhancing learning through optimal sequencing of web-based and manikin simulators to teach shock physiology in the medical curriculum

The Association of American Medical Colleges has encouraged educators to investigate proper linkage of simulation experiences with medical curricula. The authors aimed to determine if student knowledge and satisfaction differ between participation in web-based and manikin simulations for learning shock physiology and treatment and to determine if a specific training sequencing had a differential effect on learning. All 40 second-year medical students participated in a randomized, counterbalanced study with two interventions: group 1 (n = 20) participated in a web-based simulation followed by a manikin simulation and group 2 (n = 20) participated in reverse order. Knowledge and attitudes were documented. Mixed-model ANOVA indicated a significant main effect of time (F(1,38) = 18.6, P < 0.001, η(p)(2) = 0.33). Group 1 scored significantly higher on quiz 2 (81.5%) than on quiz 1 (74.3%, t(19) = 3.9, P = 0.001), for an observed difference of 7.2% (95% confidence interval: 3.3, 11.0). Mean quiz scores of group 2 did not differ significantly (quiz 1: 77.0% and quiz 2: 79.7%). There was no significant main effect of group or a group by time interaction effect. Students rated the simulations as equally effective in teaching shock physiology (P = 0.88); however, the manikin simulation was regarded as more effective in teaching shock treatment (P < 0.001). Most students (73.7%) preferred the manikin simulation. The two simulations may be of similar efficacy for educating students on the physiology of shock; however, the data suggest improved learning when web-based simulation precedes manikin use. This finding warrants further study.

Optimal learning in a virtual patient simulation of cranial nerve palsies: The interaction between social learning context and student aptitude

Background: Simulation in medical education provides students with opportunities to practice interviews, examinations, and diagnosis formulation related to complex conditions without risks to patients. Aim: To examine differences between individual and team participation on learning outcomes and student perspectives through use of virtual patients (VPs) for teaching cranial nerve (CN) evaluation. Methods: Fifty-seven medical students were randomly assigned to complete simulation exercises either as individuals or as members of three-person teams. Students interviewed, examined, and diagnosed VPs with possible CN damage in the Neurological Exam Rehearsal Virtual Environment (NERVE). Knowledge of CN abnormalities was assessed pre- and post-simulation. Student perspectives of system usability were evaluated post-simulation. Results: An aptitude-treatment interaction (ATI) effect was detected; at pre-test scores ≤ 50%, students in teams scored higher (83%) at post-test than did students as individuals (62%, p = 0.02). Post-simulation, students in teams reported greater confidence in their ability to diagnose CN abnormalities than did students as individuals (p = 0.02; mean rating = 4.0/5.0 and 3.4/5.0, respectively). Conclusion: The ATI effect allows us to begin defining best practices for the integration of VP simulators into the medical curriculum. We are persuaded to implement future NERVE exercises with small teams of medical students.

Virtual patient simulations and optimal social learning context: A replication of an aptitude–treatment interaction effect

Abstract Background: Virtual patients (VPs) offer valuable alternative encounters when live patients with rare conditions, such as cranial nerve (CN) palsies, are unavailable; however, little is known regarding simulation and optimal social learning context. Aim: Compare learning outcomes and perspectives between students interacting with VPs in individual and team contexts. Methods: Seventy-eight medical students were randomly assigned to interview and examine four VPs with possible CN damage either as individuals or in three-person teams, using Neurological Examination Rehearsal Virtual Environment (NERVE). Learning was measured through diagnosis accuracy and pre-/post-simulation knowledge scores. Perspectives of learning context were collected post-simulation. Results: Students in teams submitted correct diagnoses significantly more often than students as individuals for CN-IV (p = 0.04; team = 86.1%; individual = 65.9%) and CN-VI (p = 0.03; team = 97.2%; individual = 80.5%). Knowledge scores increased significantly in both contexts (p < 0.001); however, a significant aptitude–treatment interaction effect was observed (p = 0.04). At pre-test scores ≤25.8%, students in teams scored significantly higher (66.7%) than students as individuals (43.1%) at post-test (p = 0.03). Students recommended implementing future NERVE exercises in teams over five other modality-timing combinations. Conclusion: Results allow us to define best practices for integrating VP simulators into medical education. Implementing NERVE experiences in team environments with medical students in the future may be preferable.

Linking simulation and visualization construction through interactions with an ontology visualization

An ontology is a formalized knowledge structure understandable by humans and machines. Positioned within the interface layer, domain-specific ontologies can afford simulation model building and visualization construction. Such an ontology-enabled interface would allow modelers to interact with the semantics they are already familiar with, due to their field-specific education and training, in order to build executable simulation models. We present a methodology in which ontology visualizations serve as interface to simulation model building and visualization construction activities. Further, we describe how the ontology can be used to link simulation variables to visualization parameters, thus supporting integrative multi-modeling by allowing simulations and their corresponding visualizations to be constructed within the same interface and interaction paradigm. To demonstrate the ontology-enabled interface, we present a case study: a physiological simulation of hypovolemic shock and its corresponding three-dimensional (3D) visualization.

The impact of social context on learning and cognitive demands for interactive virtual human simulations

Interactive virtual human (IVH) simulations offer a novel method for training skills involving person-to-person interactions. This article examines the effectiveness of an IVH simulation for teaching medical students to assess rare cranial nerve abnormalities in both individual and small-group learning contexts. Individual (n = 26) and small-group (n = 30) interaction with the IVH system was manipulated to examine the influence on learning, learner engagement, perceived cognitive demands of the learning task, and instructional efficiency. Results suggested the IVH activity was an equally effective and engaging instructional tool in both learning structures, despite learners in the group learning contexts having to share hands-on access to the simulation interface. Participants in both conditions demonstrated a significant increase in declarative knowledge post-training. Operation of the IVH simulation technology imposed moderate cognitive demand but did not exceed the demands of the task content or appear to impede learning.

High-fidelity patient simulators to expose undergraduate students to the clinical relevance of physiology concepts

PHYSIOLOGY EDUCATORS are often faced with the difficulty of showing students the clinical relevance of the science they are learning. This occurs at the healthcare professional level before clinical rotations with direct patient encounters. This challenge is likely even more prevalent during undergraduate training as students are years away from exposure to an actual healthcare setting. Physiology, which is arguably the foundation of clinical medicine, is a difficult subject for students of all levels to learn for various reasons, including the fact that it is conceptual and highly integrated (8). Therefore, finding avenues for undergraduate students, especially those in healthcare career tracks, to experience the clinical relevance of physiology “in action” may help student engagement, enthusiasm, and learning of physiology as well as help guide career choices. The use of high-fidelity patient simulators (HFPSs) has expanded throughout medical, nursing, and allied health professions education in the last decades. These manikins can be programmed to represent pathological states and are used to teach clinical skills as well as clinical reasoning. First, the students are typically oriented either to the manikin or prebriefed about the specific case or scenario. This is followed by the 15- to 30-min simulation itself with a subsequent debrief about the experience (9). These HFPS experiences have been shown to improve learning and retention of physiology concepts in medical students (2, 5, 6). Interestingly, the use of HFPSs has also expanded into high school, college, and graduate schools in an effort to add problem-solving and critical thinking components to science classes (9). Gordon and Oriol (4) from the Harvard Summer Preclinical Institute have shown that student reflection reveals a deep satisfaction with the experience. Participation in these classes helped to improve confidence and reinforce humanism as well as providing clarity for future career choices (4). Although the idea of incorporating HFPSs within undergraduate courses appears beneficial on multiple levels, there are limited data regarding implementation and learning outcomes of the experience. The purpose of this report is to share the data and reflections from a HFPS experience for biomedical students in our undergraduate program. The 2-h HFPS experience was part of an upper-level undergraduate course titled “Laboratory Virtual Simulations in Physiology,” which is a mixed-mode class consisting of laboratory modules and limited face-to-face lecture time. The HFPS experience was developed and facilitated by faculty members from the University Central Florida College of Medicine and School of Biomedical Sciences. The goals of this study were to determine the feasibility of the simulation activity, whether learning occurred in the activity, and whether students were engaged during the activity. A pretest and posttest were designed and given to participants to test knowledge and perceptions of teamwork and communication skills. This study was reviewed and exempted by the Institutional Review Board of the University of Central Florida, and students participated with informed consent.