Healthcare Training in Simulated Environments
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Published: Tue, 27 Feb 2018
“Clinical simulation is pretending for the purpose of improving behaviors for someone else’s benefit (Kyle & Murray, 2008, p.xxiv).”
All respiratory therapists are trained to manage the airway of an unconscious patient. Endotracheal intubation is the most effective method of securing the airway but is a complex psychomotor skill requiring much practice. Historically, endotracheal intubation had been taught on patients, cadavers or animals, but this was not ideal. Mannequin training is one of the best options for instructing large numbers of students in a variety of skills (Gaiser, 2000) therefore the Respiratory Therapy program at TRU has adopted training on mannequins as a core component of their courses. Intubation trainers have been used for over 30 years (Good, 2003) but there is little published information on the relative merits of the available airway and intubation trainers. A variety of airway trainers with differing features are now commercially available from the low fidelity, part task trainer, that TRU respiratory therapy program utilizes, to the high fidelity, whole patient simulator that is becoming increasingly popular today.
Training health care practitioners in a simulated environment without actual patients is a potential method of teaching new skills and improving patient safety (Issenberg et al, 1999; Devitt et al, 2001; Lee et al, 2003). – pt safety
Simulations are defined as activities that mimic the reality of a clinical environment and are designed to demonstrate procedures, decision-making, and critical thinking through techniques such as role-playing and the use of devices such as interactive videos or mannequins. A simulation may be very detailed and closely simulate reality, or it can be a grouping of components that are combined to provide some resemblance of reality. (Jeffries, 2005) – definition of simulation
Computer based simulations and part-task training devices can provide a certain degree of real-world application. These focus on specific skills or selected areas of human anatomy. High-fidelity patient simulators can provide real physical inputs and real environmental interactivity. To recreate all elements of a clinical situation, a full-scale or high fidelity simulation would be used. Costs of simulators will vary widely depending on purchasing costs, salaries, how faculty time is accounted for, and other factors. (Jeffries, 2005) – simulators, high fidelity, costs Modern technology, such as high fidelity simulation offers unique opportunities to provide the “hands-on” learning. High fidelity simulation offers the ideal venue to allow practice without risk and there are an infinite number of realistic scenarios that can be presented using this technology. As an example, life threatening cardiac arrhythmias can be simulated on a life like fully computerized mannequin. Monitors, identical to those used in the clinical situation can replicate the arrhythmia and corresponding changes in vital signs. The ‘patient’ can be fully and realistically resuscitated with technical and pharmacological interventions. Viewing of videotaped performances allows personal reflection on the effectiveness of the case management. Morgan et al, 2006 – example of use of high fidelity sim.
High fidelity simulation provides a venue to teach and learn in a realistic yet risk free environment. The ‘patient’ is represented by a computer-controlled mannequin who incorporates a variety of physiological functions (e.g. heart and breath sounds, pulse, end-tidal carbon dioxide). An instrumentation computer network can replicate situations likely to be encountered in an emergency room, critical care environment or operating room. A second person controls the mannequin and the monitors. The simulator mannequin will respond on an accurate way to induced physiologic or pharmacologic interventions. The ‘patient’ will respond according to pre-set physiological characteristics (e.g. a young healthy adult or a geriatric patient with severe emphysema). In addition, the ‘patient’ has the ability to speak, move his arm, and open and close his eyes and has pupils that can dilate and constrict. The simulation room can be set up to appropriately reflect the environment, either an emergency room, a recovery room, or a fully equipped operating room. Attached monitors respond to a medical intervention. Feedback from participants in the simulated environment has attested to the ‘realism’ of the environment (Morgan & Cleave-Hogg, 2000). Morgan et al, 2006 – set up of HPS
A simulator replicates a task environment with enough realism to serve a desired purpose and the simulation of critical events has been used instructionally by pilots, astronauts, the military and nuclear power plant personnel (Gaba, 2004). The fidelity, or the “realness”, of simulations can vary in many ways, such as the use of simple case studies, utilization of human actors to present clinical scenarios, computer-based simulations, and the use of high-fidelity patient simulators that respond to real-world inputs realistically (Jeffries, 2005; Laerdal, 2008; Seropian, 2003). Recently, literature has described that using full-sized, patient simulators are a way of creating “life-like” clinical situations (Fallacaro & Crosby, 2000; Hotchkiss & Mendoza, 2001; Long, 2005; Parr & Sweeney, 2006). While simulation has been used by the aviation industry with flight training for years (Gaba, 2004), the use of a rudimentary human patient simulator in the health care field was first introduced in 1969 to assist anesthesia residents in learning the skill of endotracheal intubation (Abrahamson, Denson, & Wolf, 1969; Gaba & DeAnda, 1988). The more realistic human patient simulators were not created until 1988 and were used primarily to train anesthesiologists (Gaba, 2004).
Defining simulation in health care education
The literature on human patient simulation has tried to define several of the terms used in this study. However, there is no general consensus on many of these terms, including a debate on whether the simulator is a mannequin or a manikin (Gaba, 2006). One key term that requires specific definition for this study is high-fidelity mannequin-based patient simulator. The term “fidelity” is used to designate how true to life the teaching experience must be to accomplish its objectives (Maran & Glavin, 2003). Using this definition, fidelity becomes a scale where if given the objectives, a single piece of medical simulation equipment may be able to provide a “high-fidelity” experience for one objective but be “low-fidelity” for another objective. An example would be the insertion of a radial arterial catheter. If the objective were to only teach the psychomotor skills required for inserting the catheter, a relatively simple arterial blood gas access arm, part-task simulator would be adequate and provide a high-fidelity experience. But if the objective were expanded to include communication with the patient and members of the health care team, then the same device would suddenly become low-fidelity, as there is no feedback being delivered with catheter insertion and communication with the patient is not possible.
Beaubien & Baker (2004) noted that the term ‘fidelity’ is frequently documented as a one-dimensional term that forces a static classification of simulation devices. Individuals with this view would have difficulty agreeing with the use of the terms as explained in the previous paragraph.
Maran and Glavin (2003) offered this definition: “Fidelity is the extent to which the appearance and behaviors of the simulator/simulation match the appearance and behaviors of the simulated system (p.23).”
Yaeger et al (2004) broke fidelity down into three general classifications: low-medium-and high-fidelity and explained that low-fidelity simulators are focused on single skills and permit learners to practice in isolation while medium fidelity simulators provide more realism but lack sufficient cues for the learner to be fully immersed in the situation. High-fidelity simulators, on the other hand, provide adequate cues to allow for full immersion and respond to treatment interventions.
For the purposes of this study, the following definitions will be used:
1. High-fidelity patient simulator – A full-bodied mannequin that replicates human body anatomy and physiology, is able to respond to treatment interventions, and is able to supply objective data regarding student actions through debriefing software.
2. Low-fidelity simulator – A part task trainer or a full-bodied mannequin that replicates human anatomy, but does not have physiologic functions (including spontaneous breathing, palpable pulses, heart and lung sounds, and voice capabilities), does not have a physiologic response to treatment interventions, and does not have a debriefing software system.
Use the next two statements at the beginning of other sections on simulation:
* “Simulation is a training and feedback method in which learners practice tasks and processes in lifelike circumstances using models or virtual reality, with feedback from observers, peers, actor-patients, and video cameras to assist improvement in skills (Eder-Van Hook, 2004, p.4).”
* “Simulation is a technique….to replace or amplify real experiences with guided experiences that evoke or replicate substantial aspects of the real world in a fully interactive manner (Gaba, 2004, p.i2).”
When we are looking at the use of high-fidelity patient simulators in health professions education, we have to be aware of and not confuse the simulator with the simulation. As Gaba (2004) described, “Simulation is a technique – not a technology (i2).” The mannequins or other devices are only part of the simulation. Dutta, Gaba and Krummel (2006) noted a gap in the research literature, stating, “A fundamental problem in determining the effectiveness of surgical simulation has been an inability to frame the correct research question. Are the authors assessing simulation or simulators (p.301)?”
Simulation has many applications. The teaching of psychomotor skills seems an obvious use for simulation but there are other areas that simulation can be utilized effectively. Rauen (2004) listed several areas in addition to psychomotor skill training where simulation has been used. Her list included teaching theory, use of technology, patient assessment and pharmacology. Rauen (2004) notes that the “emphasis in simulation is often on the application and integration of knowledge, skills, and critical thinking (para 3).”
History and Development of Simulation in Healthcare education
The history of simulation in healthcare has been well documented by several authors including Bradley (2006), Cooper and Taquito (2004), Gaba (2004) and Rosen (2004) and began with the use of models to help students learn about anatomical structures. Although the use of mannequins as the simulation model is relatively new (Bradley, 2006), simulation using animals as models dates back over 2000 years. Mannequins were utilized as models in obstetrical care as early as the 16th century (Ziv, Wolpe, Small, & Glick, 2003). The more modern medical simulators originated in the 1950s with the development of a part-task trainer called ‘Resusci-Anne’ that revolutionized resuscitation training (Bradley, 2006; Gaba, 2004). Part-task trainers are meant to represent only a part of the human anatomy and will often consist of a limb or body part or structure. These low fidelity modesl were developed to aid in the technical, procedural, or psychomotor skills, such as venipuncture, catheterization and intubation (Kim, 2005), allowing the learner to focus on an isolated task. Some models provide feedback (visual, auditory or printed) to the learner on the quality of their performance (Bradley, 2006; Good, 2003).
Another general classification of patient simulators that combines some of the elements of both three-dimensional models and task-specific simulators is partial or part task simulators (Kyle & Murray, 2008). Issenberg, Gordon, Gordon Safford, and Hart (2001) used the term procedure skills simulator for this type of device. Maran and Glavin (2003) stated, “part-task trainers are designed to replicate only part of the environment (p.24).” and replicate anatomy and physiology of a single portion of the human body. As described by Beubien and Baker (2004), the skills taught with part task simulators “segment a complex task into its main components (p. i53).” Rather than creating complex scenarios commonly done with high fidelity patient simulation, part task trainers permit students to focus on individual skills instead of more comprehensive situations. Examples would be an arm with vascular structure to teach arterial blood gas procedures or a head with upper airway anatomy to practice advanced difficult airway procedures.
The second wave of modern simulation, with the development of full-scale, computer controlled, mannequin based patient simulators started in the 1960’s with the development of Sim One (Bradley, 2006; Gaba, 2004; Good, 2003). SimOne had many of the features found on the high-fidelity mannequin-based patient simulators used today. SimOne was quite lifelike, and fitted with a blood pressure cuff and intravenous port. SimOne was able to breath, it had a heartbeat, temporal and carotid pulse and a blood pressure (Abrahamson, 1997).
Patient simulators have become very sophisticated over the years and now allow a wide range of invasive and non-invasive procedures to be performed on them, as well as enabling teamwork training (Davis, Buono, Ford, Paulson, Koenig and Carrison, 2006). When they are set up in a simulated and realistic environment, they are often referred to as high-fidelity simulation platforms (HFSP) or human patient simulators (HPS) (Kim, 2005). Components of the human patient simulator (HPS) include a mannequin and computer hardware and software. The HPS has characteristics expected in patients such as a pulse, heart and lung sounds, and blinking eyes with reactive pupils. The mannequin also supports invasive procedures, such as airway management, thoracentesis, pericardiocentesis and catheterization of the bladder (Laerdal, n.d.).
Medical Education Technologies, Inc. (METI) introduced the Human Patient Simulator (HPS) in 1996. It has subsequently followed with PediaSim in 1999, a simulator utilizing the HPS software but scaled down to mimic a child. In 2005, BabySim was introduced.
While being the first to enter the market with a full-bodied mannequin for patient simulation purposes in resuscitation with the Resusci Anne in 1960, Laerdal Medical did not introduce a high-fidelity patient simulator until 2000 with the introduction of SimMan. This device does not possess all the high-level functionality of METI HPS, but does provide adequate fidelity for many medical emergency situations. The Laerdal Medical SimMan also differs from the others in that it does not operate on mathematical models for simulator responses. Instead, it operates on instructor controls combined with script-based control logics. The Laerdal Medical SimMan patient simulator is the device to be used in this study. Details of the simulator’s functions are found in appendix ____.
Aside from high-fidelity mannequin based patient simulators, there are many other types of simulation used in healthcare provider education and training. Collins and Harden (1998), Issenberg, Gordon, Gordon, Safford, and Hart (2001), and Ziv, Small and Wolpe (2000) discussed several other forms of simulation. The list includes animal models, human cadavers, written simulations, audio simulations, video-based simulations, three dimensional or static models, task specific simulators and virtual reality simulation. (Add VR reference?) Perhaps the next step in the evolution of health care teaching modalities is virtual reality (VR) simulation. Commercial VR simulators now exist to teach various trauma skills (Kaufman & Liu, 2001). In a study of the effectiveness of using a VR bronchoscopy simulator, students quickly learned the skills needed to perform a diagnostic bronchoscopy at a level that was equal to those who had several years of experience (Colt et al, 2001).
Simulation has been used for many years in the aviation and nuclear power industries and other highly complex working environments in which the consequences of error are costly (Bradley, 2006). A simulator designed to mimic the anesthesia patient was first developed in 1988, and since then, the number of hospitals and universities buying simulators for educational purposes is increasing (Henrichs, Rule, Grady and Ellis, 2002). The human patient simulator is used in health care education because it is a high-fidelity instrument that provides both educators and students with a realistic clinical environment and an interactive “patient” (Feingold, Calaluce and Kallen, 2004).
The cost of simulation is related to the level of fidelity and the technology being used. For high fidelity patient simulators, purchase costs can range from $30,000 for the Laerdal Medical SimMan or the METI ECS to over $200,000 for the METI HPS. Optional equipment available for these simulators can make the purchase costs even higher. In addition to the simulator, it is important to create a learning environment that replicates real-world settings, complete with appropriate medical equipment. Halamek et al. (2000) stated, “The key to effective simulation-based training is achieving suspension of disbelief on the part of the subjects undergoing training, ie, subjects must be made to think and feel as though they are functioning within a real environment (para 15).” Creating this environment adds additional costs to setting up a simulation-based medical education program.
Advantages of using simulation in health care education
Patient simulation of all types, including high-fidelity patient simulation, is becoming more common in many aspects and levels of healthcare provider education (Good, 2003; Issenberg, McGaghie et al., 1999; leblond, Russell, McDonald et al, 2005). The reasons behind the increased use of patient simulation include the advancement of medical knowledge, changes in medical education, patient safety and ethics. For new healthcare providers it is also important to consider the changing student demographic, as today’s students are more comfortable with technology. Issenberg, McGaghie et al. (1999) pointed out several advantages to the use of patient simulators, stating “Unlike patients, simulators do not become embarrassed or stressed; have predictable behavior; are available at any time to fit the curriculum needs; can be programmed to simulate selected findings, conditions, situations, and complications; allow standardized experience for all trainees; can be used repeatedly with fidelity and reproducibility; and can be used to train both for procedures and difficult management situations. (p. 862)”.
Advancement of medical knowledge
Medical knowledge is continually growing with new tests, medications, and technologies that all bring about innovative understandings and expertise. The problem with educating health care providers with this new knowledge is that their curriculum is of a finite length therefore innovation in the curriculum is needed in order to prepare future health care providers. Issenberg, Gordon, Gordon, Stafford, and Hart (2001) made the following comments:
“Over the past few decades, medical educators have been quick to embrace new technologies and pedagogical approaches… in an effort to help students deal with the problem of the growing information overload. Medical knowledge, however, has advanced more rapidly than medical education…Simulation technologies are available today that have a positive impact on the acquisition and retention of clinical skills. (p.16)
Changes in medical education
Healthcare provider education has typically been taught using a lecture/apprenticeship model (McMahon, Monaghan, Falchuk, Gordon, & Alexander, 2005) that relies on observation and repetition (Eder-Van Hook, 2004). Halamek et al. (2000) noted the traditional model of medical education has three components: the learner performs a reading of the literature, the learner observes others with greater experience, and then the learner develops hands-on experience. This is the traditional medical model of education that has been in use for over 2,000 years (Current state report on patient simulation in Canada, 2005).
In relation to the traditional model, Issenberg, Gordon, Gordon, Stafford and Hart (2001) observed, “This process is inefficient and inevitably leads to considerable anxiety on the part of the learner, the mentor, and at times the patient (p. 19).” McMahon, Monaghan, Flachuk, Gordon, and Alexander (2005) stated this model “is inefficient in promoting the highest level of learned knowledge, as reflection and metacognition analysis occur independently, often without guidance and only after extended periods of time when students are able to piece together isolated experiences (p. 84-85).” Customarily, this format is often referred to as the “See one, do one, teach one” model of medical learning (Brindley, Suen & Drummond, 2007; Eder-Van Hook, 2004; Gorman, Meier, & Krummel, 2000; Yaeger et al., 2004).
Halamek et al. (2000) identified several problems with the current medical education model which includes; 1. Reading of the literature does not produce competency. More active rather than passive participation in the learning experience is needed; 2. Learners may have difficulty determining if their model for observation is a good or poor model. Just because the model may be senior does not mean they are competent. 3. The variability of experiences in the apprenticeship model is high, therefore learners’ experiences will not be equal, and 4. Many training settings do not fully represent the complexity of the real world resulting in an inability of the learners to adequately practice their decision-making skills in a “real” environment.
Yaeger et al (2004) reinforced these points stating that healthcare education rely on two fatally flawed assumptions. The first assumption is that all clinical role models are effective and skilled, and all behaviors demonstrated by these role models are worthy of replication. The second assumption is that the end of the training period implies that a trainee is competent in all the skills necessary for successful clinical practice (Yaeger et al, 2004). Yaeger (2004) also noted that in the apprenticeship model, there is a need for a preceptor but this preceptor may not have the necessary skills to be an effective educator.
A predominant theme in many discussions of high-fidelity simulation is the concept of patient safety. In the education of healthcare providers, there are sometimes conflicting goals. As Friedrich (2002) commented in quoting Atul Gawande, “medicine has long faced a conflict between ‘the imperative to give patients the best possible care and the needs to provide novices with experiences’ (p. 2808).” When looking at the broader topic of medical simulation, the concept of patient safety is a frequently mentioned subject (Bradley, 2006; Cleave-Hogg & Morgan, 2002; Ziv, Ben-David, & Ziv, 2005).
Much of the incentive behind the focus on patient safety relates back to the Institute of Medicine 2000 report To Err is Human: Building a Safer Health system (Kohn, Corrigan, & Donaldson, 2000). This study reported over 44,000 people and possibly up to 98,000 people die each year in United States hospitals from medical errors. The total annual cost of these errors is between $17 billion and $29 billion. Even more alarming is the fact that these findings represent only the hospital sector of the healthcare system. The number of lives affected would be even higher if other parts of the healthcare system were included such as long term care facilities and Emergency Medical Services. In its summary of recommendations, the report specifically mentions simulation as a possible remedy, stating “…establish interdisciplinary team training programs for providers that incorporate proven methods of team training, such as simulation (p.14).”
In Canada, it was estimated there were 70,000 preventable adverse events in Canadian hospitals with an estimate of deaths associated with those errors ranging from 9,000 to 24,000 (Current state report on patient simulation in Canada, 2005). The Canadian Patient Safety Institute supports the use of simulation as a means of improving patient safety in Canadian hospitals. In the conclusion of its report on patient simulation, the institute stated:
Growing awareness of adverse events in Canadian hospitals, combined with increasing emphasis on patient safety, has changed the traditional “learning by doing” approach to healthcare education. Anecdotal evidence reveals the promising potential of simulation to fundamentally change the way healthcare professionals practice and further hone their skills, interact across disciplines, and manage crisis situations. (Current state report on patient simulation in Canada, 2005, p.23)
One of the strongest statements made regarding the ethical perspective of simulations was presented by Ziv, Wolpe, Small and Click (2003). Under the title “Simulation-Based Medical Education: An Ethical Imperative”, the authors presented an argument that not using simulation was more than just an education issue, it was an ethical issue. As they report, there is often an over reliance on vulnerable patient populations to serve as teaching models when other resources exist that would provide adequate and possibly, more superior replacements.
The education of healthcare providers requires a balancing act between providing the best in patient care while also providing learning opportunities for the healthcare professions student (Friedrich, 2002). To protect patient safety, actual patient contact is often withheld in the healthcare provider learning process to a later period in their education.
One of the principle reasons patient simulation is being indicated as a partial remedy for the medical errors crisis is its ability to impact on a particularly vulnerable time in the learning process. As Patow (2005) cited, the “learning curve” faced by many healthcare professions students is a source of medical errors. He continued, stating that the realism of many of the currently available simulators is quite high and allows for procedures to be practiced to mastery prior to being tested on real patients. But simulations offer much more than just practice. Since medical errors often result from ineffective processes and communication, simulation allows teams “to reflect on their own performance in detailed debriefing sessions” (Patow, 2005, p.39). This opportunity to review, discuss, and learn from the simulation is an important step in the learning process.
The use of patient simulation in the training of healthcare providers is not limited to new students. There is also a need to maintain education in the health professions and simulation can be utilized effectively in this area as well (Ziv, Small & Wolpe, 2000). As in other reports, Ziv, Small and Wolpe (2000) restated the shortcomings of the traditional model and explained that simulation was not just for the beginner but also for the expert who is expected to “continuously acquire new knowledge and skills while treating live patients (p.489).” These authors feel simulation, when used across the range of health professions education, can make an impact on patient safety by removing patients from the risk of being practiced upon for learning purposes.
Gaba (2004) pointed out there are also many indirect impacts of patient simulation on patient safety. These areas of impact include improvements in recruitment and retention of highly qualified healthcare providers, facilitating cultural change in an organization to one that is more patient safety focused, and enhancing quality and risk management activities.
A final point on patient safety is the ability to let healthcare providers make mistakes in a safe environment. In real patients, preceptors step in prior to the mistake being beyond the point of recoverability or if the mistake occurs (particularly for those healthcare providers who are not longer students), there is a very limited instructive value to the case.
Ziv, Ben-David, and Ziv (2005) stated, “Total prevention of mistakes, however, is not feasible because medicine is conducted by human beings who err…[Simulation Based Medical Education] may offer unique ways to cope with this challenge and can be regarded as a mistake-driven educational method (p.194).” They continued stating that Simulation Based Medical Education is a powerful learning experience for students and professionals where “students are permitted to make mistakes and are provided with the opportunity to practice and receive constructive feedback which, it is hoped, will prevent repetition of such mistakes in real-life patients. (p.194)”.
Ethical Use of Simulation (incorporate these paragraphs into previous on pt safety)
Health care educators, whether from nursing, respiratory therapy, or medicine, find themselves in similar situations in deciding how to teach patient management to their students. Bioethicists have long condemned the use of real patients as training tools for physicians (Lynoe, Sandlung, Westberg, & Duchek, 1998). Unfortunately there have been times in which the student learning has occurred to the detriment of patients (Lynoe et al, 1998). However, with the advent of high-fidelity human patient simulation approaches to learning, it may be time to adopt this method of instruction in the development of interprofessional education.
The Institute of Medicine (IOM) recently issued a report on medical errors and recommended the use of interactive simulation for the enhancement of technical, behavioural and social skills of physicians (Kohn, Corrigan & Donaldson, 1999). Numerous accounts are found in the medical literature touting the use of human patient simulation in the education of health care personnel at all levels, from student to attending physicians. Patient simulation is used for training personnel in several areas of medical care such as trauma, critical care, surgery and anaesthesiology, mainly due to the extensive skill required to perform adequately the procedures and techniques relevant to these areas. Several researchers have demonstrated the effectiveness of simulation in the skill development of medical personnel (Morgan et al, 2003; Lee, Pardo, Gaba, Sowb, Dicker, Straus, et al., 2003; Hammond, Bermann, Chen & Kushins, 2002). In areas with low technology, such as internal medicine and in acute care areas providing less procedural skills but greater decision making requirements, the use of simulation in the education of its clinicians has progressed (Ziv, Wolpe, Small & Glick, 2003). Despite the growing support for the use of simulation in health care education, there is not yet enough evidence to support its use.
Simulation Research in Medical Education
In 1998, Ali, Cohen, Gana & Al-Bedah studied the differences in performance of senior medical students in an Adult Trauma Life Support (ATLS) course. This course uses simulated scenarios to both teach and evaluate students’ performance in trauma situations. The students were divided into three groups; 32 medical students completed a standard ATLS course, 12 students audited the course (without participating in the sessions or taking the written exam) and a control group of 44 matched students who had no exposure to ATLS. Of note is that some participants from all three groups were doing clinical hours in trauma hospitals during this study while others were not. The participants were observed while managing the standardized (live) patient in simulated trauma and non-trauma scenarios. The participants’ management of the sessions was scored on
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