Anesthesia simulation

Anesthesia simulation is a branch of simulation technology related to education, training, and competency evaluation in the medical field of anesthesiology. It can involve simulated human patients, educational documents with detailed simulated animations, and training on low fidelity partial task training devices. The main purpose of simulation is to allow students to learn technically difficult skills without putting patients at risk for injury. By using simulation to train medical professionals we can reduce the incidence of errors and reduce patient harm.

History

Full environment simulation (FES) is an adjunct to medical education that has been extensively developed by anesthesiologists. In fact, anesthesiologists developed the first mannequin used to teach airway and resuscitative skills. Resusci Anne, designed by Asmund Laerdal, was developed to teach mouth-to-mouth resuscitation. The concept of basic life support training using a mannequin-based simulator would grow out of this simple design as Laerdal partnered with Peter Safar, a Baltimore anesthesiologist, and Dr. Bjorn Lind, a Norwegian anesthesiologist, to enhance his simulator’s capabilities and realism.

Truly computer-driven simulators were developed in the mid-1960’s with Sim One, a full-scale mannequin with a chest capable of rise-and-fall action during respiration, blinking eyes and dilatign pupils, and a jaw which could open and close. A single Sim One was manufactured and was eventually lost to obscurity largely because it was ahead of its time, despite the fact that those residents trained on the simulator acquired airway management skills quicker than their colleagues. The Harvey cardiology mannequin was also developed in the 1960’s but unlike the Sim One it has had sustainable use to the present day. This simulator is capable of a wide array of cardiac disease scenarios, has been researched and validated extensively and has evolved over time to include multimedia programs which enhance its fidelity.

Towards the end of the 1980’s, two teams of anesthesiologists, one from the University of Florida (Drs. Michael Good and John Gravenstein) and the other from Stanford (led by Dr. David Gaba) developed realistic mannequin simulation. They combined engineering skills and the initiative of using simulation in education, for team training and with an aim towards improving patient safety. The development of mathematical modeling programs for human physiology and [...] pharmacodynamics and pharmacokinetics led to the development of modern mannequin and screen-based simulators. Various evolutions of these mathematically driven simulators have been developed and are described elsewhere.

Today the Human Patient Simulator (HPS), based on the Gainesville simulator and now manufactured by Medical Education Technologies Inc. (METI) is the prototypical full-scale, mathematical-model-driven product. This simulator can be used to stage full-scale simulations whereby realistic monitoring, physiologic response to drugs, and high-fidelity pathological conditions can be encountered by participants.

Types of Simulations

A simple classification system of simulator types uses three categories: part-task trainers, computer-driven mannequins and virtual reality simulators on a continuum from low to high fidelity. Part-task trainers represent anatomical parts for teaching and/or evaluating skills (e.g., plastic airways for intubation) and are generally passive, non-computerized models. However, more advanced part-task trainers have been designed such as the Endoscopy AccuTouch System by Immersion Medical. This is a computer-driven tool used to simulate flexible bronchoscopy and upper and lower gastrointestinal flexible endoscopy and may be familiar to many readers. These simulators also include cursory responses to noxious stimuli, including audible sounds of discomfort from the simulated patient, increased heart rate, and blood pressure along with the ability to administer medications commonly used for sedation.

Computer-driven mannequins not only possess anatomically correct features, but through mathematical models respond to stimuli and administration of medications. Such mannequins are ideally suited for immersive or full-environment simulation in which entire teams of healthcare providers can train to perform tasks, manage potentially deadly scenarios, and improve teamwork skills, including leadership, communication, delegation and prioritization. Full immersion virtual reality (VR) is the newest and next generation of simulation where user can interact with all of the elements of the simulated environment. Although visual, auditory and haptic (touch and pressure) feedback are all available in VR simulations, this technology is still in its infancy and much work needs to be done in order to fully incorporate VR technology into the field of medical simulation.

Full environment simulation (FES)

Full-environment simulation (FES) includes the patient (simulator), other healthcare professionals and ancillary equipment and supplies designed to replicate the clinical environment. Incorporating the simulated patient into a simulated operating room environment, complete with an anesthesia machine, monitors, and adjuncts commonly found in real operating rooms, allows participants to suspend disbelief thus creating a highly effective, state-dependent learning environment. The center for Human Emulation Education and Evaluation is a working laboratory for patient safety and professional study on the campus of the Mount Sinai Medical Center in New York. The HELPS center is a good example of how full environment simulation can be put to use creating a tool for education and evaluation of physicians.

The Mount Sinai Medical Center has the distinction of being the first Beta test site and the first medical center in the New York metropolitan tri-state area to possess a human patient simulator. Housed in a dedicated educational laboratory of operating rooms equipped with standard monitoring and anesthesia equipment, healthcare providers from a variety of disciplines and educational levels use this latest technology in human simulation to discover and learn basic and advanced principles of physiology, pharmacology, and anesthesiology. The simulator environment is also used to teach and practice the management of complex perioperative medical events and emergencies to both house staff and attending physicians. The facility uses METI’s Human Patient Simulator, a full-scale patient mannequin with palpable pulses, breath, and heart sounds that physiologically responds to intravenous and inhaled drugs through the interaction of sophisticated cardiovascular and pulmonary computer driven models.

Efficacy

Many reports have discussed the efficacy of simulation-based education for teaching basic and advanced skills in anesthesiology, management of rare and critical events including advanced cardiac life support (ACLS) protocols, and team training through crisis resource management. FES provides the unique opportunity to not only practice procedures but to allow educators the ability to stage realistic scenarios in which the principal focus can be human behavior and interaction. Standardized patients, played by actors, can be used in conjunction with FES to lend an even greater level of reality to simulation. In this environment, participants can be allowed to make mistakes and experience bad outcomes without patient harm. These adverse outcomes can facilitate the generation of negative emotions amongst the participants; no healthcare professional wants to be responsible for contributing to patient harm through a bad clinical outcome, especially when witnessed by colleagues. One of the major manufacturers alleges that its device “exhibits clinical signals so lifelike that students have been known to cry when it ‘dies.’”

General Uses and Benefits of Simulated Patients

The growing interest in medical simulation for education and assessment of physicians has been fueled by many of the same factors that led to the use of simulation in the aviation and nuclear industries. The importance of simulation is evident in aviation, where commercial pilots take their first flight only after a rigorous simulation program. The extensive use of simulation in the aviation industry has not been driven by evidence, but by intuition and common sense. To date there is (relatively) small body of evidence that simulator training improves health-care education, practice, and patient safety, but, Gaba argues, "...no industry in which human lives depend on skilled performance has waited for unequivocal proof of the benefits of simulation before embracing it."

An educational imperative is one obvious utility of simulation. Simulation is learner-centered in that the participant’s education receives highest priority. There exist no competing patient needs and therefore the participant is afforded a unique opportunity to perform tasks without the looming stress of medical error. Medical clerkships and post-graduate training rely upon apprentice-based, chance encounters with patients where learning time is limited and not standardized. Simulation eliminates these limitations and in doing so benefits teachers by allowing for an optimal learning environment and a pre-designed curriculum that emphasizes points deemed germane by the instructor. Also, presentation of uncommon but critical situations in which a rapid intervention is required is possible. This offers the learner the benefit of experience with a particular disease state in a safe environment rather than a purely “textbook” knowledge of the subject.

Immersive simulation, in particular, allows for assessment and education that extends beyond simple cognitive measures. A participant or team of participants can be evaluated and trained in domains of clinical knowledge, communication and teamwork and procedural and technical skills in one environment and in one simulation session. An expert for the domain(s) of interest can then debrief the participant(s). Debriefings are vital as one can learn from mishaps that occurred during a scenario and also speak openly about perceived and actual errors and limitations without fear of liability, blame or guilt. Errors are deliberately allowed to occur and reach their end whereas in real life a more capable clinician would necessarily be called. In this way, participants can see the results of their choices. Patient safety and medical errors have come to the forefront of healthcare since the Institute of Medicine released To Err is Human: Building a Safer Health System in 2000. (30) The effective integration of simulation into medical education and assessment can address this modern healthcare challenge.

In addition to the more obvious and intended benefits of simulation, the ethical benefits are also pronounced. Patients entrust healthcare providers with their well-being and enter into a relationship in which they believe their providers to be expertly trained. It follows that being trained in simulated scenarios before a real patient encounter reduces a patient’s exposure to less seasoned professionals. Thus, patients theoretically receive a higher quality of care than they might otherwise get from those trained in apprentice-based systems where the adage of “see one, do one, teach one” may in fact overestimate the experience the provider has attained. As alluded to previously, other high-risk fields such as aviation and the nuclear power industry have safely integrated simulation into their personnel training programs and competency evaluations.

Modern medical simulation

The American Board of Emergency Medicine employs the use of medical simulation technology in order to accurately judge students by using "patient scenarios" during oral board examinations. However, these forms of simulation are a far cry from high fidelity models that have surfaced since the 1990s. Due to the fact that computer simulation technology is still relatively new relative to flight and military simulators, there is still much research to be done about the best way to approach medical training through simulation. That said, successful strides are being made in terms of medical education and training. A thorough amount of studies has have shown that students engaged in medical simulation training have overall higher scores and retention rates than those trained through traditional means.

The Council of Residency Directors (CORD) has established the following recommendations for simulation: Simulation is a useful tool for training residents and in ascertaining competency. The core competencies most conducive to simulation-based training are patient care, interpersonal skills, and systems based practice. It is appropriate for performance assessment but there is a scarcity of evidence that supports the validity of simulation in the use for promotion or certification. There is a need for standardization and definition in using simulation to evaluate performance. Scenarios and tools should also be formatted and standardized such that EM educators can use the data and count on it for reproducibility, reliability and validity.

The medical learner at any stage–undergraduate, graduate, or postgraduate–is truly an adult learner. Defined in various ways by education theorists, the adult learner, by all accounts, is seen to learn by different methods and for different reasons in comparison with earlier stages in his education. In 2008, building on the work of other education scholars (including Knowles, the father of andragogy, or adult learning theory), Bryan et al. described 5 adult learning principles that apply to the medical learner. These are an adaptation of the assumptions of andragogy, which emphasizes the role of experience and self-direction as well as the need to know the benefits of knowledge and its potential applications before one embarks on the instructional journey. The challenge then is to create effective educational pathways within this paradigm.

Five Adult Learning Principles That Apply to the Medical Learner:

1. Adult learners need to know why they are learning. 2. Adult learners are motivated by the need to solve problems. 3. The previous experiences of adult learners must be respected and built upon. 4. The educational approach should match the diversity and background of adult learners. 5. Adults need to be involved actively in the process.

The complexity grows, however, when the technical aspects of clinical instruction are introduced. Clinical skills, on the simplest level, are psychomotor skills learned via reinforcement and requiring straightforward instruction. In some ways, clinical skills would seem easier to master because students tend to remember 90% of what they do yet only 10% of what they read. However, clinical skills consist of more than motor memory. They require the integration of problem solving skills, communication skills, and technical skills in the setting of a complex medical context, and they require practice.

The ultimate goal in medical education is expertise or mastery of one’s trade. Deliberate practice is an educational technique used to produce expert performance contingent upon 4 conditions: intense repetition of a skill, rigorous assessment of that performance, specific informative feedback, and improved performance in a controlled setting. The true goal of deliberate practice, similar to the true goal of medical education, is to produce an expert or master of any trade. As Eppich et al. explained, unless the goal is improved performance, merely participating in the activity will not lead to mastery. It would appear then that one way to improve medical education is to seek a mechanism for deliberate practice.

A recent study by Wayne et al. assessed the value of using simulation technology and deliberate practice to enhance acute resuscitation skills. This study of 41 second-year internal medicine residents using deliberate practice to teach advanced cardiac life support (ACLS) showed statistically significant improvements in education outcomes, including compliance with standard ACLS protocols as well as retention of skills and knowledge after 14 months. In evaluating simulation as an educational tool, Issenberg et al and McGaghie et al described the features enhancing its utility.

Simulation provides the tools and the paradigm to enhance medical education, but it depends on intense preparation and support from faculty as well as buy-in from the participants. The ability to provide immediate directed feedback is the primary advantage of simulation. This opportunity is typically lacking in the clinical setting. It also effectively addresses the diversity of both learners and situations with its adaptable, programmable structure. The main limitation of simulation is learner-dependent, as it requires full participation and engagement by the individual.

Features and Uses of High-Fidelity Medical Simulations That Lead to Effective Learning include the following:

1. Mechanism for repetitive practice 2. Ability to integrate into a curriculum 3. Ability to alter the degree of difficulty 4. Ability to capture clinical variation 5. Ability to practice in a controlled environment 6. Individualized, active learning 7. Adaptability to multiple learning strategies 8. Existence of tangible/measurable outcomes 9. Use of intra-experience feedback 10. Validity of simulation as an approximation of clinical practice

FES addresses many of the challenges in today’s medical education. First, it provides a medium and mechanism for clinical skill instruction. Everything from basic interview skills to lung auscultation to emergent cricothyrotomies can be practiced in a simulated environment. That environment allows for relevant, active learning with feedback, these being important components of clinical skill development. Next, it creates a safe environment for practicing with new technologies and, importantly, ensures that practice occurs without endangering patient or practitioner safety. Traditional practice of ‘‘see one, do one, teach one’’ may no longer be ethical.

FES is also an ideal environment for the promotion of teamwork and communication. Many clinical problems cannot be solved simply by identification of the diagnosis; they often require resource management and teamwork, practical skills well suited to simulation education. A study by Ottestad et al demonstrated that simulation could be used to reliably assess non-technical skills such as interpersonal communication and task management. n Ottestad et al.’s study, housestaff were videotaped managing a standardized simulated septic shock patient in teams, and a benchmark checklist of clinical and non-clinical skills was developed. The tapes were reviewed by 2 of the study authors trained in skill review, and interrater reliability was found in the assessment of both clinical and non-clinical skills (r = 0.96 andr = 0.88, respectively).

Lastly, training with high fidelity mannequin simulation improves knowledge consolidation. Wayne et al demonstrated by both retrospective case log review and simulator testing that comparing the acute cardiac arrest management of residents trained by simulation and those not trained on the simulator showed that students learning new material with the use of simulation retained knowledge further into the future than students studying with more traditional methods. Medical learners may also benefit from experiential learning, a model explained by David Kolb that emphasizes a process of learning building on concrete experience. His model describes 4 stages: (1) concrete experience, (2) observation and reflection, (3) abstract concept formation, and (4) active experimentation in which generalizations are tested and new hypotheses are developed to be tested in future concrete experiences. The simulation experience affords an excellent opportunity to expand on this model. Learners are thrown into a simulated concrete experience that allows them to progress through the cycle, ideally developing skills and knowledge to be applied in future simulated or actual concrete experiences. One of the most important parts of the experiential learning cycle is debriefing, a process that is often difficult to perform in the typical clinical learning experience. In a simulated environment, debriefing can be successfully accomplished.

A study by Savoidelli et al found simulation without debriefing showed no improvement in non-technical skills in comparison with simulation with either oral or videotape-assisted oral feedback, which showed significant improvement (P > 0.005).

Further reading:

Simulation Training and Assessment: A More Efficient Method to Develop Expertise than Apprenticeship.Cooper JB, Murray D. Anesthesiology. 2009 Nov 30.

Steadman, Randolph H. MD; Coates, Wendy C. MD; Huang, Yue Ming MHS; Matevosian, Rima MD; Larmon, Baxter R. PhD; McCullough, Lynne MD; Ariel, Danit BASimulation-based training is superior to problem-based learning for the acquisition of critical assessment and management skills Critical Care Medicine: January 2006 - Volume 34 - Issue 1 - pp 151-157

Levine AI, Bryson EO Medical Simulation, Introduction Journal of Critical Care, Vol. 23, No. 2, June 2008, p. 156

Bryson EO, Levine AI The Simulation Theatre: A Theoretic Discussion of Concepts and Constructs that Enhance Learning Journal of Critical Care, Vol. 23, No. 2, June 2008, pp. 185-187