The Prodigal Sim
Alan Merry
A certain man had two sons. And the younger of them said to his father, Father, give me the portion of goods that falleth to me. And he divided unto them his living. And not many days after the younger son gathered all together, and took his journey into a far country, and there wasted his substance with riotous living. And when he had spent all, there arose a mighty famine in that land; and he began to be in want.[1]
Simulation is established in aviation and is gaining traction in anaesthesia for training and research, and in the assessment of performance. Simulation centres are proliferating, but there are few standards and there is considerable variation in infrastructure and expertise. Commercially available simulators have many powerful attributes, but also have limitations, notably in physiological and pharmacological modelling, and in reliability. Detractors point to high costs, limitations in realism, and lack of validation, and remind us that findings or experiences in the simulator may not apply to the clinical situation.[2] Simulation can seem expensive. In 1997 it was estimated that setting up a simulation centre in the USA cost approximately US$590,000, and running it cost approximately US$150,000 per year.[3] A more recent estimate was (approximately) US$876,000 and US$361,000 respectively.[4] There is intense competition for limited resources for training and research. Many simulation centres have found financial sustainability elusive. Is it possible, then, that we are dealing with a prodigal sim? Have we who work with simulation wasted our substance in riotous (or at least imprudent) living? As the first flush of enthusiasm for adopting simulation from aviation has given way to the hard realities of actually using it effectively in anaesthesia to improve outcomes for our patients, are we at risk of finding ourselves in a time of famine (in the context of financial support), and facing want?
Simulation in aviation has advanced from the very basic Link Trainer in 1927 to a level of fidelity which makes it possible for a pilot to become fully licensed to fly an Airbus A320 (for example) or to be credentialed to land in foreign airports entirely in a simulator. The economics of this are interesting. An actual A320 costs NZ$18000 per hour to run, while the A320 simulator costs only NZ$700 per hour. In contrast to anaesthesia, service and training are kept entirely separate. Simulators may be categorised according to their physical and functional characteristics. Not all simulation requires simulators – role play for example, only needs participants.[5]
Simulation has several attributes of value to adult education.[6] It allows learners to be actively engaged in the educational process, in solving real life problems, and in gaining relevant (albeit simulated) clinical experience and it provides opportunities for practice, for feedback and for reflection.[7] Simulation has been used to teach anatomy, physiology, pharmacology, various clinical skills, teamwork and crisis management to undergraduates and postgraduates, across many disciplines. However, evidence that simulation enhances education is limited: outcome measures have varied and controls have been few, and not always the most effective alternative educational methods available. Simulation is often portrayed as the answer to modern-day barriers to learning on patients, but this assumption is far from proven. Effective learning is dependent on educational principles which apply whether simulation is used or not, and these are sometimes neglected by enthusiasts for simulation. Clarity about the objectives of any educational exercise is essential, and the choice of educational method should be informed by the particular characteristics of the task in question, not by the fact that one happens to own a simulator. The use of shortcuts to facilitate simulation-based education may actually serve as a poor role model for clinical practice, and have the unexpected and undesirable effect of teaching bad habits. The notion that simulation is worthwhile in itself is as much a trap for the tyro educationalist as opposition to simulation may be an impediment to progress for some traditionalists.
As with teaching, there is no better way to study clinical questions than in real patients, but barriers to doing this may include risk to patients, the fear of medico-legal repercussions for participants, and the cost when the events of interest are rare and large studies are needed. With simulation, clinical scenarios can be standardised, participants can be observed and videotaped, rare events can be produced on demand, and the environment is relatively safe for all concerned.[8, 9] Again, there is much to learn. Our group is developing methods applicable to evaluating human performance in the operating room. It is possible to study the same question at different levels of simulation, beginning with simple and efficient micro-simulations, and then validating findings in more comprehensive and realistic scenarios. Simulators with autonomous model-driven physiology provide opportunities for powerful, objective, task relevant outcome measures, such as severity and duration of hypoxia or hypotension.
Simulation for assessment is accepted in aviation, and pilots who fail are immediately removed from flying until remedial training can be provided and competence demonstrated at a repeat assessment. On the basis that evidence for the validity of simulation for the assessment of anaesthetists is still needed, there has been reluctance to use simulation in the assessment of anaesthetists. It is time to re-evaluate this position, even if conclusions about competence are restricted to the context of the simulated environment. Our experience in research suggests that many participants appreciate explicit feedback, and there is no greater reason to doubt the relevance to clinical practice of performance in a simulator than there is to doubt that of performance in a multiple-choice examination.
Scepticism on the part of traditionalists to aspects of simulation in anaesthesia is understandable, but has our behaviour really been reminiscent of the prodigal son? Certainly resources have been devoted to simulation; we have travelled far from traditional methods of education and research in medicine. We have taken risks and may at times have made mistakes, but we have learned new ways of teaching and of doing research whose value is supported by an increasing body of evidence.[8-10] Adherence to established principles is essential in these endeavours and agreed standards in relation to simulators and simulation are sorely needed, but in the end simulation is just another method for use in education, research and the assessment of performance. Access to the clinical environment is increasingly problematic, and when this “famine” really takes hold, we may be very pleased to have developed simulation to the point of being an adequate alternative “substance”. Our rejoicing may then rival that of the father who killed the fatted calf.
1. Luke 15: 11-14 The Holy Bible 1953. London: Eyre and Spottiswoode Limited.
2. Editorial: simulation-saviour or Satan? Advances in Health Sciences Education, 2003. 8: 1-3.
3. Kurrek, M M and Devitt, H J. The cost for construction and operation of a simulation centre. Canadian Journal of Anesthesia, 1997. 44: 1191 - 1195.
4. McIntosh, C, Macario, A, Flannagan, B, Gaba, D M. Simulation: What does it really cost? Simulation in Healthcare, 2006. 1: 109 Abstract #1473.
5. Cumin, D and Merry, A F. Simulators for use in anaesthesia. Anaesthesia, 2007. 62: 151-162.
6. Weller, J. Evaluation of simulation-based education in the management of medical emergencies. MD Thesis, 2005, University of Auckland.
7. Kaufman, D M. Applying educational theory in practice. BMJ, 2003. 326: 213-6.
8. Merry, A F, Weller, J, et al. A simulation model for reduction in error. Anaesthesia and Intensive Care, 2005. 33: 670-671.
9. Weller, J, Merry, A, Warman, G, Robinson, B. Anaesthetists' management of oxygen pipeline failure: room for improvement. Anaesthesia, 2007. 62: 122-126.
10. McGaghie, W C, Issenberg, S B, Petrusa, E R. Simulation--Savior or Satan? A rebuttal. Advances in Health Sciences Education, 2003. 8: 97-103.
Time of Presentation
0830
