Simulation Training in Endoscopy

G&H Historically, what has been the standard training regimen for development of endoscopic skills?

JC Standard endoscopy training has generally consisted of one-on-one education by an experienced endoscopist teaching a trainee, who performs supervised procedures in actual patients. In some programs, there are supplemental didactic educational materials, including information about the anatomy and an introduction to the actual scope apparatus, but the mainstay of education has been, and remains, one-on-one, hands-on training.

G&H What are the advantages of the one-on-one method utilizing actual patients?

JC The major advantage is that one-on-one training allows for immediate feedback, both in terms of technical methods and cognitive advice, which promotes proficiency and good technique. This setting allows trainees to observe experienced endoscopists using their knowledge and judgment to deal with unique and difficult situations, as well as working on them firsthand.

G&H Are there disadvantages associated with this method?

JC There are disadvantages from the perspective of each of the interested parties. From the patient's perspective, there is the obvious disadvantage of undergoing a procedure performed, at least in part, by an inexperienced physician. From the perspective of the instructor, procedures involving trainees take longer to perform, and these procedures can add to the time pressures that most medical faculty already face. From the perspective of thetrainee, the inherent pressure involved in learning a new skill is compounded by learning on a live patient. Time constraints for completing a procedure can also lead to a more stressful learning environment. Depending on the clinical circumstances, there may be fewer opportunities for unlimited question-and-answering and feedback from the instructor. Perhaps this limitation is most apparent when considering the experience of the fellow undergoing training for the endoscopic management of gastrointestinal bleeding. Often during these cases, endoscopists do not have the luxury of time to discuss appropriate therapeutic options and review required steps; in fact, the trainee may be allotted limited time to try to perform the hemostasis techniques—in the interest of the safety of the patient, the mentor may need to take over.

Another limitation of traditional training is that pathology is encountered in an uncontrolled and often unpredictable fashion, which can result in a somewhat haphazard educational experience. Some abnormal findings, although important to understand and experience, are rarely seen, and trainees may not be exposed to them enough to develop proficiency in their recognition or management. The need not only to learn but to repetitively practice a technique may be hampered by the dependence on what clinical scenarios happen to present on any given day.

G&H Can you describe the role that animal models and cadaver-based training have taken in endoscopic education?

JC Ex-vivo animal models have been validated as a useful method for training and are more widely available than ever. Tese nonlive animal-tissue models have been used to simulate colonoscopy, upper endoscopy, endoscopic retrograde cholangiopancreatography procedures that do not require fluoroscopy, and even endoscopic ultrasound models. A wide range of endoscopic therapeutic techniques have been reproduced quite realistically. Typically, frozen tissue can be sent and thawed with relative ease for insertion into a platform model that goes on a stretcher or table. Local representatives from equipment manufacturers generally supply animal-ready real endoscopes.

Work with animal models is generally performed with intensive, one-on-one expert instruction at a dedicated time, often a day-long weekend session at the trainee's institution, or as part of a workshop or regional course provided by a professional society. The New York Society for Gastrointestinal Endoscopy has been staging these courses for the past 8 or 9 years in conjunction with their annual course in December. Trough the American Society for Gastrointestinal Endoscopy's Interactive Training & Technology (IT&T) Center, courses are now available for first-year fellows throughout the country. More advanced “Beyond the Basics” courses have been developed at this center for individuals in practice aiming to learn specialized new techniques such as placement of enteral stents, and the opportunities at this national center continue to expand.

Cadavers are available and have been used in certain courses to help with more complex anatomy. For example, a recent natural orifice transluminal endoscopic surgery (NOTES) course held in New York utilized cadavers for part of the training. Live animal porcine courses are limited due to obvious cost and ethical concerns, especially with the availability of ex-vivo models.

There have been data to demonstrate that supplemental training on animal models leads to objective improvement in endoscopic skill. Our group performed a multicenter study in New York to validate the role of intensive hemostasis training in serial sessions, utilizing the compact Erlangen Active Simulator for Interventional Endoscopy (EASIE) model. We were able to validate improvement in skills relating to different techniques with supplemental EASIE practice, when compared to standard experience during the same time period.

The ex-vivo animal simulators are commercially available and fairly easily transported along with frozen tissue specimens to allow for their frequent utilization in local workshops around the country. When considered along with the IT&T courses, sessions at Digestive Disease Week, and sessions at other large meetings, this manner of training enjoys a growing acceptance as a standard supplement to traditional endoscopy education and as an important resource for those already in practice who wish to learn new skills or refresh old ones.

G&H How do computer-based simulated training systems differ from animal models?

JC With the computer simulators, the trainee is first oriented to a machine, which is similar to a standard desktop computer that is attached to a mannequin. The student is assigned a password and login to access the simulation software. The simulator utilizes a real endoscope or a device very similar to a real endoscope with forced-feedback technology installed at the tip. This technology gives the trainee the sense and feel of tissue resistance. When the instrument is passed through the mannequin, the operator can go through a series of simulated cases. There are varying levels of sophistication in the feedback provided by the computer regarding the amount of pressure applied, the amount of air and discomfort the trainee is causing, and whether the endoscope is looped. In colonoscopy simulation, time spent to reach the cecum can be measured, and various pathology specimens can be presented. Trainees can actually write notes and have an instructor review their findings and interpretation. Some programs include ancillary printed explanations of the cases presented for the trainee to obtain more immediate feedback about their findings. Basic hand-eye coordination skill-building games, again utilizing the scope, are also included.

The computer simulators are obviously very easy to reuse once they have been purchased, although the upfront cost can be prohibitive to many programs. They also allow trainees to work constructively without supervision, and this potential for independent study is one of the main advantages over other methods of training. A multicenter study that we conducted in New York validated the usefulness of a computer simulator in the early stages of training for colonoscopy.

Although the computer simulators do have therapeutic modules, these simulators are generally thought to be mainly useful for novices learning to perform diagnostic endoscopy. There has been no validation of computer simulator training for therapeutic procedures. In fact, it has been much more difficult to realistically reproduce all the different steps in a therapeutic procedure, and for these scenarios, animal models are considered more useful. Animal models offer a more realistic simulation of tissue sensation and the ability to modify pathology and actually perform procedures with various accessories. Probably the greatest limitation of the computer simulators remains their high cost and relative lack of availability.

G&H Is there a role for any of the simulator models in competency testing for endoscopists?

JC Use in competency testing is something of a holy grail for simulator systems because once a validated competency test is in place, there will be an even greater justification for use and availability of the simulators. To date, no study has been able to correlate performance level on a computer-based simulator with performance proficiency on actual procedures. There have been many studies showing that experts perform better than novices on computer simulators. However, this does not mean that a certain score on a simulator test can be used to establish competency. A valid test of competency will require better definition of competency criteria on real procedures and computer simulator procedures that are more difficult to perform and even more realistic than currently available versions.

With animal models, it is much easier to break skills down into discrete steps, to evaluate the skill level as measured on the simulator, and then to compare it to performance in actual procedures. This process was shown in the New York hemostasis study led by Dr. Juergen Hoch-berger, the real pioneer of this field of ex-vivo training.

G&H What else can be done to maximize the usefulness of simulator devices in endoscopic training?

JC Development of simulators that work well and can provide valuable training is only part of the equation. It is also important that instructors have an opportunity to learn how to best utilize the technology to provide the best training. An instructor who is a good endoscopist is not necessarily going to be a good teacher of endoscopy, so it is important that instructors receive training in teaching trainees and optimal use of available simulators.

It is also important that further work be performed to increase the portability of simulators to further facilitate local training on an informal level. More opportunities for model-based training need to be created for practicing gastroenterologists who hope to retool as technology advances. Success in this regard will require the ongoing support of industry sources, which provide scopes, accessories, and other necessary components.

As for the computer simulators, we should increasingly take advantage of their ability to show a variety of pathologies and to provide a medium for interactive feedback and questions. Future validation work will need to demonstrate sufficient value in either training or competency testing in order to justify their large upfront expense.

G&H Do you foresee the development of an expanded role for simulator techniques in future endoscopic training?

JC I see the role of simulation training expanding on many levels. Simulators can be utilized as research tools for new techniques and procedures, which can be developed, to some extent, on these models before being tried in live animals. It is a much less expensive and more ethical manner in which to conduct research. For example, new accessories for endoscopic submucosal dissection or NOTES procedures could be tested in these models before using them in live animals.

Furthermore, with an increasing number of endo-scopists interested in and needed for the performance of advanced therapeutic procedures, simulator models will become an intrinsic and absolutely essential part of a step-wise approach to training. It is, again, more efficient and more ethical than starting with live animal models. The Natural Orifice Surgery Consortium for Assessment and Research (NOSCAR), the organization driving the development of NOTES procedures, has recognized training as one of the key areas for research in order to develop and spread the use of this technology.

I hope that it will soon become standard practice that with each new and complex technique that is developed, a specific program of how best to train for performance is established. This practice will ensure that practitioners have standard methods for learning procedures and assessing their own competency before working on real patients. Incorporation of simulator technology into these advances will be increasingly prominent, particularly as the potential risks involved in these procedure become greater.