Simulation is now widely use in the field of medicine to give students the opportunity to apply the basic principles they learn in the classroom to true-to-life problems that would require analytical reasoning and crucial decision making while allowing enough room for mistakes and without endangering or risking the health of real patients. It involves the use of a variety of a device to make the scenes and circumstances appear realistic (Beaubien & Baker, 2004, p.i52). One of the most recent and amazing advancements in this field is the development of simulators or life-like computerized mannequins containing sophisticated mechanical parts that mimic the human organ systems thereby producing programmable physical reactions like pulses, heart sounds, breath sounds, respiratory rate, pupil reactivity, bodily secretions and others expected in response to specific interventions and/or situations.
Since its breakthrough from the late 1960s into the early 1990s, different types of simulators, from low fidelity to high fidelity, are now commercially available and used by universities and medical centers worldwide (Good, 2003, p.4). Fidelity refers to the degree of accuracy the simulator resembles the physical, environmental and psychological properties of a real object or being (Beaubien & Baker, 2004, p.i52). Such that low fidelity simulators are lifeless models used in traditional teaching methods to train students for specific tasks like endotracheal intubation and cardiac compression. The limitations of the older simulators observed by Gaba and De Anda (1988) includes absence of mannequin movement and minimal or confusing physical signs (p.387).On the other hand, the high fidelity simulators are the most realistic life-sized mannequins capable of the most varied levels and degrees of responses, mimic authentic changes in body functions based on the specific problem case and display interacting physiological and pharmacologic parameters on real life scenarios (Gaba, 2000). Examples of the high fidelity simulators are the ISTAN full body mannequin, Laerdal's SimMan Universal Patient Simulator, Gaumard's Susie S2000 and the Human Patient Simulator by Medical Education Technologies, Inc., which are all "computer-model-instructor-driven" units with elaborately programmed cardiovascular, pulmonary, pharmacological, metabolic, genitourinary and neurological systems (METI, HPS, n.d., p.3) that allow them to exhibit blinking, pupillary response, chest movement and breath sounds, palpable pulses and heart tones, bleeding and body fluid excretion, and accurately imitate human responses to medications, cardiopulmonary resuscitation, intubation, ventilation and catheterization.
The mannequins are attached by cords to the control system, which is a laptop computer, a signal generator and a monitor where vital signs are displayed (SimMan Universal Patient Simulator, n.d., par. 1). Depending on the case scenario, the mannequins' vital signs and other organ functions including heart rhythm are controlled by highly skilled facilitators via computer softwares that come with the mannequins (About the Simulation Center, n.d., par. 5) hence they do not require an additional interactive ECG simulator to manipulate the heart rhythm. The simulators monitor and record all actions taken from simple vital signs taking to more complex interventions like compressions and intubation and mount the expected commensurate response as dictated by the computer software. All responses including blood pressure, arterial oxygen saturation, and 5-lead electrocardiogram are likewise recorded. These records can easily be printed and reviewed by the facilitator and student to enhance the learning experience.Despite their many features that promise better teaching methods for students, the high fidelity simulators do not come without their limitations. The first limitation is its high cost. The SusieÒ S200 set including the cordless mannequin, wireless tablet PC, software scenarios, blood pressure cuff, collar, instructions and CDROM cost $27,995 (Gaumard, n.d.).. In contrast, the one of the most widely used simulator, the Human Patient Simulator cost around $175,000 (Karmin & Schmidt, 2005) including the mannequin, computer, monitor, HPS6TM Software, 30 Pre-programmed Adult Patient Profiles and 60 Pre-programmed Simulated Clinical Experiences (METI, HPS, n.d., p.4)
Furthermore, the simulator response is largely dependent on the software that contains its programming. Although all types of patient profiles and case scenarios can be created, modifying the simulator's responses depends on the availability of the pre-designed software required to allow the specific programming. The Human Patient Simulator package comes with modules that include 60 pre-programmed simulated clinical experiences, appropriate corresponding intervention scenarios and software application (METI, Learning, p.4). If one of the modules and its software like the ACLS Learning Module based on the 2006 AHA Guidelines or the interactive EKG module is unavailable then the simulator's heart cannot be prompted to mimic emergency cardiac cases like Acute Coronary Syndrome, Acute Ischemic CVA and rhythm disturbances by a simple click on the laptop keyboard. The simulator can still be used to perform and evaluate the other parts of the ACLS course like vital signs taking, IV line insertions, mouth-to-mask ventilation with the resulting chest rise and finally chest compressions though simulated response to this may not be seen.To be able to use the simulator for the other parts of the ACLS course, someone will need to design the six scenarios (asystole, ventricular fibrillation, supraventricular tachycardia, ventricular tachycardia, symptomatic bradycardia, and pulseless electrical activity) of the course based on the ones found in the AHA Instructor Manual then program them into its accompanying software like the HPS6TM. Hence training of present personnel or hiring of trained ones will be required for the proper use and maintenance of the simulator.