"By nature, men are nearly alike; by practise they get to be apart," Confucius, 551-470 BC
Virtual reality and simulated environments are an increasingly important part of our lives. Their attraction is that people can gain exposure to situations that would otherwise be too dangerous for a novice. People can pick up skills without putting themselves or anyone else at risk, or practise working in environments they would not normally encounter. Aircraft pilots can learn to land a plane for instance, and astronauts can practise space walks. However, while there is obvious application for simulation in the field of medical training, there are as yet few simulators that have demonstrated predictive validity. What hurdles need to be overcome to reach this goal? And what is the current state of the art?
Dr Derek Gould, Royal Liverpool University Trust, UK, is part of a task force on simulation devices at the Cardiovascular and Interventional Radiological Society of Europe (CIRSE), and was lead author of a position statement co-published recently by CIRSE and the Society of Interventional Radiology (SIR) in CardioVascular and Interventional Radiology and Journal of Vascular and Interventional Radiology. These guidelines warn "caveat emptor": essentially saying that while simulated reality has a lot of potential, especially as working time restrictions limit the time available for medical trainees, "we must resist the temptation to consider procedural simulations and clinical experiences interchangeable".
CIRSE, SIR and the Radiological Society of North America (RSNA) have established individual medical simulation task forces with the objective of advising on the use of simulators in interventional radiology, including standards for developing tests, certification and validation of models. Dr Aalpen Patel, University of Pennsylvania and the leader of the SIR Medical Simulation Task Force, told Interventional News, "Each Society has [independently] formed its own task force to deal with its own interests. However, we recognised that as radiologists we must speak in unison, so we decided to co-operate and form a joint task force." This international task force will make recommendations to the individual governing bodies of the societies and radiology as a whole; the SIR Medical Simulation Task Force will make recommendations to the SIR executive council. If these recommendations are approved they will form the basis of an infrastructure to support medical simulation strategy for radiology. Other radiology organisations need to have representation as well.
The first aim of the task force is, explains Patel, to survey the field. "There are a lot of simulators out there and many require validation. In an intuitive sense you feel that simulations should work, but we need to gather data. Realistically, simulators must be used in parallel with validation efforts. Before any simulations can be tested, the task force must decide what it is testing for. When you train someone you need a benchmark that says 'you've reached proficiency', so that you know when to stop. But we don't have a definition of proficiency and we don't have those benchmarks," he elaborated.
Measurements: the what and how
This is where Drs James R Duncan and Craig Glaiberman, from Mallinckrodt Institute of Radiology, St Louis, MO, come in. They are helping the task force conduct a series of tests. Their area of expertise is expertise; what it means to be proficient and how that can be measured. Duncan explained to Interventional News: "We're interested in simulation: in the training of students and assessing how they progress. We and others also see that simulation could be used as a means of testing procedural skills, but that's a long way down the road."
The first step in solving this problem, is to determine how known skills transfer to simulation. Hence the SIR task force created a project called EXPERTISE: EXpert Practice Evaluation using Real TIme Simulated Environments, and took it to ISET (International Symposium on Endovascular Therapy; Miami, FL, 22-26 January, 2006). "EXPERTISE at ISET was designed to test whether we could conduct such a study at a large meeting and also test our working definition of expertise," Duncan explained.
First off, EXPERTISE is looking at a simulation of renal stenting on the VIST machine (from Mentice). "We chose the kidney because we knew that most people [at ISET] would be familiar with it, and it's simple enough to collect data," Duncan related. The process included a 20-25 minute orientation on the simulator and a 30-60 minute data collection session, allowing for between one and five repetitions. The team made video recordings of the fluoro screen, simulator interface and hand movements of the test subjects. In all, they got 21 datasets representing more than 50 simulations. "That's many hours of videotape," he noted.
By testing the experts, the task force hoped to isolate one part of the learning curve: the adjustment to a new environment. Experts know how to perform the procedure so their early experience with the simulator illustrates how quickly they can adjust their skills to that device. An analogous situation is with a rental car; there is always a period of adjustment to a new vehicle, even for an experienced driver. Experts will also point out the limitations of the simulation. "Some people recognised that the simulation was good, but that some things in it were different from reality," he recalled. "However, all of them recognised the power of practice. If this sort of simulation had been available during their training, the majority said they would have liked to have used it."
Stepwise learning
In sports - and indeed in other skilled areas such as music - practice is broken down into component parts that can be repeated until the practitioner has mastered that particular skill. For example, a footballer may practise taking spot kicks, a gymnast may practise handstands, and a pianist may practise scales. Duncan commented: "Medical simulations at the moment cover the whole procedure, not steps in sequence. That is not a good way to practise. Trainees are often thrown into the deep end and have to sink or swim. In what other high-stakes endeavours do we train people this way?" Simulations can be used to identify the weak parts of a trainee's technique, which can then be isolated and rehearsed.
EXPERTISE will be conducting further tests at the upcoming SIR meeting (30th March to 4th April, Toronto, Canada). Patel continued: "At ISET we proved that it is feasible to do testing in a large meeting setting. At SIR we'll do an extension of those tests on the Mentice as well as add a second simulator - the Angio-Mentor from Simbionix...again in renal stenting.
"Eventually, we must also take a bottom-up approach: define the problems at hand (perform a task analysis and define metrics); isolate engineering problems and then design and implement solutions. This will have to be a multidisciplinary effort where physicians, engineers, mathematicians, physicists, computer scientists, etc. work in concert to achieve a common goal. Industry, academia, societies and funding agencies must also work together to move simulation forward."
The future for simulation looks rosy; the main question is, 'How long until it is proven?' Patel predicted: "In the short-term, the apprenticeship model will not be replaced, but we will have an adjunct. In the future, in a few decades, we anticipate that a lot of practice and training in procedure-based medicine and surgery will be done on simulators, but we're not there yet. Overall, I think medical simulation is here to stay. The growth rates of its use and of the medical simulation industry as a whole will depend both on research efforts in multiple disciplines and on how fast we can persuade the governments and the funding agencies of its importance for patient safety." And before that can be done, we need to improve our understanding. Duncan concluded: "Practice is the common denominator underlying expertise in most human endeavours, we just need to learn how to effectively employ simulation for medical training and then unequivocally prove that practise makes perfect."
|
