Simulated People Save Real Lives

 

Class of ’83 | To learn how to practice real-world medicine and make it more human, sometimes you need a fake. Dr. René Gonzalez M’83 GM’86 figured out that conundrum, and the result was SimMan—a highly realistic, functioning simulator whose willingness to suffer botched procedures and even “death” can improve the lives of patients and doctors alike.

A dozen years ago, Gonzalez was teaching medical residents the intricacies of intubation—sticking a tube into a patient’s mouth and down the trachea—when a light bulb went on over his head. Back then, residents and other trainees still learned their craft by practicing on patients. Gonzalez, then a professor in the University of Pittsburgh’s Department of Anesthesiology and Critical Care Medicine, would stand over their shoulders; if a problem arose, he or another instructor would step in and take over. That was good for the patients, but not so good for a resident who would someday have to perform that same procedure in less-than-perfect circumstances.

True, they did occasionally practice on “static” mannequins that had no vital functions, but that didn’t give them any hands-on training for when a patient’s jaw tightens or her tongue swells. And some day, Gonzelez knew, they’d have to deal with it.

“I took a step back and said, ‘I think we ought to think about new ways of teaching,’” recalls Gonzalez, now chief anesthesiologist at St. Luke’s-Quakertown Hospital in Pennsylvania. “Technically, there was no reason why we couldn’t animate a fine, anatomically accurate mannequin, make it actually breathe and generate EKG signals, tighten its jaw so it’s not that easy to intubate, make its tongue swell—really simulate the whole range of patient anatomy.”

He and a mechanically inclined colleague—Dr. John Schaeffer, whose résumé included an engineering degree—started by implanting a small inflatable cup in the tongue of one of those static mannequins, to make it swell. Then they implanted one in the jaw joints, to make it tighten.

“Those hidden mechanisms allowed the instructor to make it ‘come to life’ by simply inflating and deflating syringes connected to the mannequin by concealed thin plastic tubes,” Gonzalez says. By doing so, “we could easily and realistically simulate real-life phenomena such as the tongue and airway swelling, and broncho-spasm, which might be encountered in a patient suffering a severe allergic reaction.”

They soon upgraded the manual air syringes to cheap air compressors, which allowed them to add breathing and other life functions to the mannequin’s repertoire. They gave it the ability to “speak” by implanting a concealed speaker in its head; an instructor with a microphone would then play Edgar Bergen to its Charlie McCarthy. They also created a monitor that displayed the mannequin’s vital signs—which were also controlled by the instructor.

Gonzalez and Schaeffer began using their jerry-rigged simulator in 1995, and later that year, Gonzalez challenged his department at Pitt to incorporate a simulator for an airway-management course.

“We used our prototype simulator to teach,” he recalls, “and the response was unbelievable. We got rave reviews. That validated our belief that it was a very important educational technology that should be used.”

Medical Plastics Incorporated, which had manufactured the static mannequins they used, produced their first “live” mannequin and in 1998, Gonzalez and Schaeffer entered a partnership with the Laerdal Medical Corporation. The union of Laerdal’s software and manufacturing expertise and Medical Plastics’ prototype simulator gave birth to SimMan and AirMan. Since then they have added EKG signals, blood pressure, pulse-oximetry (which measures pulse and the amount of oxygen in the blood), and a host of other realistic body functions. SimMan, in fact, has been used by the Mathias J. Brunner Instructional Technology Center of Penn’s School of Nursing [“Gazetteer,” January/February 2001].

“Having a library of scenarios of cases, the system assures that your trainees will have to manage almost every kind of medical crisis that they are likely to encounter in their professional careers,” says Gonzalez. “It’s unbelievable how the residents buy into this. All of a sudden, they start talking back to the ‘patient’ and interacting with it.” Furthermore, the cost of the simulators ranges from $12,500 to $25,000, making them affordable to most teaching hospitals.

SimMan and his colleagues have also “revolutionized” medical training for military personnel, notes a recent article in The New York Times Magazine: “Fake blood squirts from blown-off limbs, mucous and tears stream from chemically burned faces, plastic bones jut from compound fractures.” Sometimes the dummies “die,” but that’s all right: “Killing a dummy in the classroom is good practice for keeping real soldiers alive.”

Gonzalez stresses a supportive approach to training.

“We don’t want to destroy trainees’ self-confidence,” he says. “We want to gently but firmly get them up to speed—to improve performance so that when they have a real patient, they’re prepared.”

Gonzalez is excited about the newest addition to the SimMan family: SimBaby, a “pediatric patient simulator.”

“Little babies are very, very difficult and challenging,” he explains. “When we get called to an emergency room to operate on a little baby, everybody gets very nervous and tense, because they’re so little and technically difficult—there’s not much margin for error. There’s a lot of demand for this, and the company is responding to it.”

For Gonzalez, SimMan actually represents a triumph in the struggle against the dehumanizing effects of medical technology.

“Medicine in general over the last few decades has become so high-tech,” he says. “The effect is dehumanizing. But we frequently have scenarios in which SimMan is speaking, then gets very sick. This is simulating a human being—you have to talk to them, explain what you’re doing. We try to teach [students] that you should explain to a patient what you’re doing because you’re trying to help them.”

Bottom line: it works.—S.H.

© 2004 The Pennsylvania Gazette
Last modified 07/01/04