October 6, 1997
Life-like simulator readies health professionals for real-life emergencies
On an operating table lies the figure of a young man, covered in blue-green sheets, his chest rising and falling, his thumb twitching. Behind his head several monitors beep, a ventilator whooshes. At his left is a tray of instruments. Surrounding him on this day are four fourth-year medical students and their instructor, Dr. Brian K. Ross, associate professor of anesthesiology.
Their patient is Mr. Jones. His chart says he’s a 28-year-old male with a nail embedded in his foot. The students are told to ready him for general anesthesia. Mr. Jones has been through this before. He is a computerized, full-size mannequin, programmed to respond to treatment. As in life, he pulls through his ordeals just fine most of the time.
“The patient simulator,” said Dr. Frederick Cheney, professor and chair of anesthesiology, “is modeled after flight simulators that train pilots to handle unforeseen problems. Anesthesia, like flying, is very safe, but the rare crashes are spectacular. An anesthesiology resident could go through all his or her years of training and never face a potential mishap. The patient simulator can stage various crises so that, when a difficult circumstance does occur, health professionals are well-prepared to deal with it.” The reenactments were chosen from common anesthesia-related clinical emergencies and published case reports.
Back in the simulation room, the medical students establish an airway for the patient, tape his eyelids shut to prevent dry eyes, administer painkillers and anesthetics, give oxygen, then wait those long seconds for the patient to resume breathing on his own as he recovers from the anesthetic.
Each student has a turn to anesthetize and awaken the mannequin. They quickly pick up the rhythm of the routine. Everything is going smoothly when the patient’s heartbeat falters. One student commands, “Start CPR.” The students try to resuscitate Mr. Jones by injecting the proper drugs and putting paddles to his chest, while their minds race to figure out the cause of his demise. In time, a student notices the oxygen is flowing poorly and fixes the malfunction.
Mr. Jones can enact more than 30 other events, including diabetic coma, congested lungs, kidney failure, blood clots and a dangerous drop in body temperature. He can react either normally or idiosyncratically to common anesthetics, as well as to more than 90 other medications. He can breathe spontaneously or with mechanical ventilation. He has heart and lung sounds, detectable pulses in his neck and wrists, and measurable blood pressures at various points in his body. The simulation center can be re-configured to resemble an emergency room bay, intensive care unit, or a supermarket aisle where a man has collapsed.
“The Patient Simulation Center gives students and clinicians hands-on practice in basic to advanced skills,” Ross said. “All simulations take place in real time with trainees using actual instruments and drugs for the procedure. Many beginning students can sing the song, that is, recite what must be done. We teach them to dance the dance, that is, turn the knobs, read the monitors, pick out the medication, uncap the needle, pump the oxygen bag.”
During the scenarios, trainees practice leadership, teamwork and communication, with each other, the patient and the patient’s family. Ross coaches by filling in the voice for each role. He envisions that the Center might bring together students from a variety of fields — surgeons, nurses, paramedics, pulmonary and critical care residents — to train together, just as they would work alongside each other after they finish school. The mannequin can also help teach physiology, by demonstrating human respiration and how the heart and lung function, as well as pharmacology.
Medical students scheduled at the Center can repeatedly perform essential procedures, such as starting intravenous medications or inserting a breathing tube into the trachea, until they feel confident. Before beginning their hospital rotations, residents can acquire some advanced skills, and the more experienced can refresh their knowledge.
Just as important, through the dramas that take place in the Simulation Center, health-care personnel find different ways to handle the tensions that arise in themselves and their colleagues during high pressure times. They come to grips with the limits of medicine.
“Because the setting is realistic, trainees often feel as they would if the events were in fact happening, ” Ross said. “Our role as teachers is to help students develop their practical abilities and judgment and evaluate their progress, but also to guide students through the emotional demands of being responsible for a patient.”
Dr. Howard Schwid, associate professor of anesthesiology, designed the computer simulations in collaboration with Dr. David Gaba at Stanford, who built the robotic mannequin. The Department of Anesthesiology funds the Patient Simulation Center, with support from several medical, electronics and space/aeronautics industries.