Fig. 40.1
Changes in physician culture (Reprinted from Morrison et al. [12], with permission from Wiley)
To help address this, medical education has naturally evolved over the past 40 years—first, with the focus on small group, case-based learning and second, with the introduction to clinical medicine occurring earlier in the students’ education. Beginning in 1969 at McMaster University in Ontario [9], case-based learning and small group formats began to permeate modern medical schools. By 2003, 70% of all US medical schools reported using problem-based learning (PBL) in the preclinical years [10]. Problem-based learning was designed to integrate basic and clinical sciences and represented a fundamental shift from lecture-based learning. The hallmark of PBL is small student-led teams, working together and applying basic science principles to help solve a clinically based case. Problem-based learning is thought to improve retention by focusing students on larger scientific principles, fostering independent learning, expanding teaching methodology, and allowing learning to occur in a more realistic setting [11]. Additionally, problem-based learning teaches students skills critical to working as a team; in order for students to best manage the case, they must communicate well, work together, and teach and learn from one another [12]. It has been suggested that prior to the emphasis of case-based learning, mastery of basic science was presented as an end unto itself, instead of emphasizing its importance and application to the practice of clinical medicine. In case-based learning, students understand why basic science instruction is relevant for their future as physicians [9]; however, despite its benefit, schools primarily used PBL to complement formal, more traditional teaching, with only 6% of programs in 2003 using PBL for more than half of their instruction [10].
Schools also began to experiment by introducing clinical experiences upon entry into medical school, rather than waiting until the later clinical years. In the 1990s, medical history and physical exam skills were still taught in a classroom—a setting devoid of patient encounters. Schools experimented with making these tasks more realistic by allowing students to practice their history and physical exam skills on real or standardized patients. Students were given opportunities to use these skills early in their medical education and to integrate them with other courses; surveys revealed that students responded favorably to those changes [13].
Flexner Revisited
Acknowledging both the changes in medical education, the shifting culture of the physician, as well as the changes in healthcare and science, multiple groups revisited the Flexner Report at its centenary and used that opportunity to issue new guidelines for medical education [2, 5]. The International Association of Medical Science Educators (IAMSE) surveyed leaders in medical education, including the national organizations of multiple basic science specialties. The consensus of the various groups was that basic science studies should be early and throughout the 4 years of medical school to improve knowledge retention. They advocated for increased integration of the basic and clinical sciences, with an emphasis on feedback and mastery of knowledge, rather than having basic sciences front loaded into the medical school curriculum. In one suggested approach, which they termed “ICE” (Ideas, Connections, and Extensions), students are first introduced to an idea, they then connect that idea with other teachings to place it within a contextual framework, and finally they extend the teaching by applying it to real-life examples. One of the suggested methods to improve the basic science and clinical integration is via the use of simulators [5].
The Carnegie Foundation, who commissioned the original Flexner Report, also chose to review the state of medical education at the 100-year anniversary of Flexner’s seminal work. Central themes in the commission’s recommendations were the need to make the learning process more learner centric, the “integration of formal knowledge and clinical experience, and the development of habits of inquiry and improvement” [2] (Fig. 40.2). Many of their recommendations, including connecting formal teaching to clinical experiences, providing challenging problems and giving students the ability to participate in authentic care, and incorporating teamwork into the curriculum, are well suited to simulation. Simulation lends itself to integration of basic science and clinical work and promotes both teamwork and scientific inquiry by engaging learners in challenging problems and giving them tools with which to participate.
Fig. 40.2
The Carnegie Report of 2010 (Reprinted from Irby et al. [2], with permission from Wolters Kluwer)
Simulation Is Widely Practiced in Medical Schools
Medical simulation is most often associated with clinical education; indeed, the earliest examples of medical simulation involved obstetric mannequins, and mannequins designed to teach airway and resuscitation, which have existed since the 1950s [14, 15]. In the intervening years, the field of simulation has seen vast improvements in the fidelity and accuracy of these models, and its use has become widespread in medical education. A 2010 survey of 90 medical schools by the AAMC showed that 84 and 91% of respondents used simulation in the 1st year and 2nd year courses, respectively. Per the survey, the most common courses in which simulation was employed were Clinical Skills, Introduction to Clinical Medicine, and Physical Diagnosis, suggesting that while simulation use is widespread in the preclinical years, it is still predominantly being used to enhance clinical medicine experiences rather than for basic science education (Fig. 40.3). Less than half of the schools surveyed used simulation in nonclinical subjects such as anatomy, pharmacology, and physiology [6].
Fig. 40.3
Use of simulation in medical education. From AAMC Survey, September 2011 (©2011 Association of American Medical Colleges. All rights reserved. Reproduced with permission)
To some degree, simulation in preclinical education is not a new concept. Anatomy courses, in which students dissect cadavers to learn the relationships between physical structures, have been a part of medical education for centuries. Physiology and pharmacology courses have long employed animal labs to simulate the physiologic responses to pharmacologic and physiologic intervention. These animal labs are particularly useful for augmenting lecture material by demonstrating core physiologic concepts, such as cardiac and pulmonary function, and the physiologic responses to perturbations to homeostasis. Students must generate hypotheses, manipulate variables, and observe and record their effects; the labs allow participants to integrate core concepts and appreciate the interrelatedness and unpredictability of live bodies [16]. Animal labs are not without their limitations—they are expensive and time-consuming, employ an animal surrogate to teach about the human body, and are fraught with ethical considerations. They present a large amount of data quickly, requiring students to focus on numerous variables simultaneously [16]. Should students miss a critical feature of the experiment, it is difficult to go back and redo that portion. There are a finite number of interventions (such as drugs) that can be performed per session—and if a mistake is made, the organ cannot be “reset.” There are limitations on the measurements, which can be performed on an organ—especially within the economic constraints of the student laboratory. Due to changing cultural attitudes towards vivisection, some students have difficulty focusing on the goals of the experiment [16], whereas others have found that a large majority of students exposed to a dog laboratory found it to reinforce lecture material, despite approximately 20% of students reporting discomfort in using dogs to demonstrate pharmacologic concepts [17]. As technologic capabilities have expanded, high fidelity and computer simulators seemed ideal replacements for these animal labs.
Simulation in Preclinical Years
Simulation for clinical education, both in clerkship training, residency, and postresidency, has been extensively studied, with the earliest published report from 1969 [18]. A recent meta-analysis, spanning 20 years of data, showed that simulation-based medical education with clinical practice was superior to traditional medical education for acquisition of skills that ranged from laparoscopy and central venous catheter insertion to advanced ACLS and cardiac auscultation [19]. As the equipment and expertise have become more widespread among medical school and training programs and faculty have become adept at their use, it is no surprise that they have moved into the preclinical years.
Problematically, research on simulation in the preclinical years is sparse and typically consists of reports from one center. A 2007 conference on Educational Research rated simulation the highest priority for educational research (out of 11 possible options) [20]. One key item discussed by researchers is the need for simulation use to be integrated throughout the medical school curriculum, so that students are able to develop expertise over time [21] and benefit from repetitive practice [7]. While these statements refer to task-based simulation, it can be inferred that by introducing simulation earlier, students can develop more general simulation skills: teamwork, facility with mannequins and computers, and familiarity with terms and devices. Students’ reflections on their first encounters with patients reveal them to be anxious and insecure—fearful of all there is to remember, a belief that they have insufficient knowledge and skills and guilt over using patients for “practice” [22]. Using simulated patient encounters, even if their primary role is to cement and supplement basic science concepts, may relieve some of that anxiety. A major challenge to integrating simulation more fully into the preclinical years is well-designed, well-validated simulators and simulations that educators will accept as a suitable replacement or function to enhance existing practices and educational activities.
Using Computer Simulation to Teach Basic Science
There are some benefits of using computer models to teach basic science:
1.
Original experiments can be recreated more easily—Classic experiments, such as the original experimental work by Starling [23], are relatively easy to construct and provide the opportunity for students to follow the same path of discovery.
2.
Some measurements or interventions are easier to demonstrate with simulation than in vivo—Pulmonary venous pressure or ventricular volume is technically very difficult to determine due to the constraints of measurement within a living organism. Measuring cell membrane voltages is difficult due to the sensitivity of equipment to ambient noise and is realistically impossible during a busy lab class. These phenomena are relatively easy to demonstrate with simulation as no environmental noise is present in the simulated screen-based environment.
3.
More interventions can be performed within a given time—The rapidity which a simulation model can be loaded and “prepared” allows multiple experiments on a theme within a given learning session. This is especially true for more complex interventions. A single experiment can be performed several times with each sequence measuring different variables in quick succession.
4.
A simulation can be reset—Animal organs have a limited lifespan ex vivo, and any experimental error is likely to necessitate a fresh preparation. The ease with which a computer simulation can be restarted gives the educator more flexibility to allow students to commit mistakes and take the results to their conclusion.
5.
Virtual organs can be studied in situ—Studying the heart or lungs as isolated organs belies the fact that their function depends on their environment (in these examples, the vascular system). Giving epinephrine to an isolated heart would increase the heart rate and force of contraction. However, giving epinephrine to a heart in situ would also increase the afterload (which in turn affects the heart work, coronary perfusion, and cardiac output) and has an effect of contracting plasma volume and thereby increasing the preload as well.
6.
Entirely virtual systems can be low cost—Although designing the computer program can be expensive, the marginal cost is thereafter very small as the program can be shared globally. This is in contrast to vivisection, with high marginal and running costs which can be shared via teleconference only partially if at all.
Best Practices in Preclinical Simulation
Whereas simulation in clinical years, especially simulation related to acquisition of procedural skills, has been studied extensively, simulation in preclinical education has not. Most published data has been on individual schools’ experience with simulation and/or small, single-center pilot studies, and the published literature includes data on computer- and mannequin-based simulation. However, there have been similar themes that run across these accounts and provide a useful framework for discussion of simulation in basic science education.
Complement of Lecture-Based Material
In all reports, the simulator is used to enhance, rather than teach, the primary material. The simulated cases should be designed to enhance course objectives and goals [24]. Typically, simulators require the consolidation of knowledge gained from the lecture hall, independent study, and real-life experiences of the students, who have had limited experience with clinical medicine. Because the goal is not to treat and cure the patient, but to explore and expand upon basic science foundations, students should be encouraged to suggest and use drugs/interventions that may not exist or be optimal treatment but are physiologically and/or pharmacologically plausible [24]. For example, if the simulated patient was exhibiting bradycardia, students could elect to give atropine (a medication that opposes vagal action), epinephrine (a beta-agonist), or say “we should give a drug that would oppose the vagus nerve.” Simulation is also best served when it is integrated carefully into the curriculum, allowing students to contextualize the scientific material which they have been presented [25]. Much like simulation cannot replace clinical experience, simulation should not replace traditional basic science education. It requires thoughtful placement into the curriculum, serving to enhance and exemplify teaching, but not be the primary learning modality, and is optimal when it is a mandatory, not optional, activity [7].
Expert Instructor, Defined Group Size, and Defined Timeline
Most reports indicate that simulation groups function best with 1–2 expert instructors, who can both provide accurate and physiologically sound responses to student intervention and have expertise in the working of the software [24, 25]. Having experts assist with simulation also allows prompt recognition, and correction, of any inaccuracies within the simulator and ensures that students do not leave the simulation session with misconceptions about the normal physiologic and/or pharmacologic responses [25]. The cases should be managed exclusively by the students, with instructor observing closely and interjecting only to guide (but not rescue) the students should they become stuck or suggest an inappropriate intervention [24]. Groups should be small enough so that all students can participate and be engaged and large enough to obligate students to work as a team. Team training is increasingly recognized as a critical skill in caring of patients, as medical students will eventually be required to work with other physicians, nurses, social workers, and other allied health professionals [7, 12], and by introducing team training early into the medical school curriculum, students will develop tools for successful teamwork. Additionally, research has shown that when students are required to teach each other, and use data to solve problems, they learn more than when they are listening to lecture or are reviewing notes [12] and that students working in collaborative settings demonstrate more enthusiasm for collaborative approaches compared to students working in lecture-based settings [13]. However, care should be taken to avoid a too large a group, because when groups become too large, students are not able to participate as well and may not be able to observe relevant changes [26]. We generally limit our mannequin-based simulation groups to ten or less.
Deliberate Practice and Individualized Learning
The educational literature increasingly recognizes that for optimal performance to occur, certain criteria of deliberate practice must be met, including repetitive performance of the skill (including cognitive skills) and skills assessment with specific feedback [7]. Deliberate practice has been validated in clinical skills such as bedside cardiology, advanced cardiac life support, surgical skills, and invasive procedures [19]. Data on the use of deliberate practice in learning and integrating basic science knowledge are lacking, but studies have shown that students perform better on examinations when the test items are designed as clinical vignettes, suggesting that retention is improved when students are required to use basic science in a clinical context rather than as isolated facts [5]. Active participation by learners allows them to focus on the core concepts that they need to master and proceed at a pace that best suits them [7]. To further promote individualized learning, some centers have implemented “simulator on demand” sessions that allow students to reserve time with the simulator and trained facilitators and explore topics which they have found difficult [25].
Debriefing
High-quality simulation requires scheduled and thorough debriefing by a clinician or other expert teacher [15]. In a 2005 systematic review of best practices in medical education simulation, almost half of the papers reviewed listed feedback as the most critical feature of simulation [7]. The teacher’s role is to integrate the features of the case with the objectives of the course, assist the students in reflecting on their experience in caring for their “patient” [24], and compare and contrast the methods of treatment employed by the students. The facilitator also guides preclinical students in the subtleties of the language and syntax of patient care—discussing the chief complaint of the patient, the ways in which students form and test hypotheses, and conclusions they draw from the signs and symptoms the patient demonstrates. In this way, the students are better prepared with an organizational foundation for their clinical years [24].
Feedback is essential to medical simulation and one of the most challenging for preceptors to master. A study comparing oral, videotape assisted, and no debriefing found that oral and videotape-assisted feedback were equally successful in improving nontechnical skills (teamwork, task management, situation awareness, and decision making) but that participants who had not received feedback had no improvement on a posttest [27]. Successful feedback can be videotaped, oral, or built into the simulator [7], but should include 12 evidence-based best practices, which have been adapted by McGaghie to simulation feedback (Table 40.1).
Table 40.1
Evidence-based best practices in simulation feedback
Debriefs must be diagnostic |
Ensure that the facilitators create a supportive learning environment for debriefs |
Encourage team leaders and team members to be attentive of teamwork processes during performance episodes |
Educate team leaders on the art and science of leading team debriefs |
Ensure that team members feel comfortable during debriefs |
Focus on a few critical performance issues during the debriefing process |
Describe specific teamwork interactions and processes that were involved in the team’s performance |
Support feedback with objective indicators of performance |
Provide outcome feedback later and less frequently than process feedback |
Provide both individual- and team-oriented feedback, but know when each is most appropriate |
Shorten the delay between task performance and feedback as much as possible |
Record conclusions made and goals set during the debrief to facilitate feedback during future debriefs |
The difficulty in providing feedback that meets best practices is that it is labor, resource, and time intensive. Facilitators need to be trained in administering simulation and providing feedback; because simulation is often done in small group settings, multiple facilitators are required.
Students Appreciate and Value Their Simulation Experiences
Overall, students rate simulation experiences very highly, believing them worthwhile and recommended for future courses and other students (Table 40.2).
Table 40.2
Student rating of simulation experiences
Study author and date | Was simulation experience: | Recommend for future years/other courses (% who agreed) |
---|---|---|
Worthwhile? | ||
Zvara, 2001 [29] | 95%—worthwhile | 92% |
85%—contributed to understanding | ||
Samsel, 1994 [17] | 4.78 out of 5 | 4.89 out of 5 |
5 = very useful | 5 = highly recommended | |
Tan, 2002 [27] | 94.5% | 96% |
Rodriguez-Barbaro, 2008 [30] | 81% | NA |
Gordon, 2006 [31] | 90% | 90% |
Heitz, 2009 [32] | 97% | NA |
Numerous studies, across multiple centers and fields of study, show students believe that simulators enhance and improve their knowledge of physiology [6] and allow them to more easily grasp concepts [26] and see realistic changes [26]. Students and teachers who have used computer modeling to simulate renal and cardiovascular physiology have reported improved integration and understanding of physiologic processes and assisted in conceptualizing “whole-body homeostasis” when combined with traditional lecture-based learning [28]. When computer simulation has been applied to neurophysiology to demonstrate membrane potentials, a large majority of students believed that the program increased their understanding [29]. While such self-efficacy data represent “soft” outcomes on the surface, having students believe in their own education is a major challenge to educators in many fields. Almost universally, simulation improves student confidence in themselves and in the instruction they received. That alone can be a victory for educators.