A distracted driver accelerates through a stop sign, knocking a rider off his bike. Soon an ambulance blares onto the scene. Medics rush out, check the man’s vital signs, and intubate him to allow him to breathe. They load him onto a stretcher and transport him to a nearby medical facility, where the doctors immediately get to work.
The patient may survive. Or not. Even if he doesn’t the medical team can review what they did wrong and try again, this time perhaps saving his life. Because this patient is not alive. He’s a simulation.
Until recently, doctors mostly trained by first watching procedures, then practicing them directly on patients. Researchers estimate that deaths from medical errors range between 44,000 and 98,000 every year. Nearly one million additional injuries are also attributed to medical error. “So you don’t want to be the first one that the doctor or nurse works on,” says John Anton, founder of the Florida-based simulation company Information Visualization and Innovative Research (IVIR). “Give them the opportunity to repeat situations they’re going to have to face—that’s what simulation is all about.”
Once, doctors might have used a hard plastic figure to stand in for a patient. Today’s mannequins simulate breathing, exhibit a pulse and mimic other vital signs, and can even “respond” to treatments. They offer a safe way for medical students, nurses, and emergency medical technicians (EMTs) to get their hands on patients and practice procedures over and over, literally gaining a realistic feel for applying lifesaving methods before they ever come in contact with a suffering human being.
A major breakthrough in medical simulation took place more than 40 years ago, when Michael Gordon of the University of Miami invented a mannequin that he named Harvey, after an honored professor. Harvey could embody a number of the different cardiac diseases a doctor might confront; and depending on the disease, a stethoscope to the chest encountered any one of a number of different heart sounds. Transformative changes in technology have resulted in the latest versions of Harvey, who can now mimic dozens of cardiac and lung diseases with all their appropriate rushes and gurgles.
In 1996, Medical Education Technologies, Inc. (METI), based in Florida, began selling the first whole-body human simulators. Instead of lifeless, immobile mannequins, these models intricately mimic human physiology, with palpable pulses, discernable breathing, and the ability to talk and to respond to treatments. The “patient” can be programmed for any type of physiology and disease. According to Lou Oberndorf, CEO of METI, “It opened up an enormous number of possibilities in the ways to teach.”
Today’s simulators take advantage of the latest technology to go beyond simulating the vital signs and responses of diseases. The latest versions are plumbed to excrete from every orifice: they spurt blood at the site of a severed artery, and clear liquid streams from their eyes and noses to mimic the effects of a biological attack.
Beth Pettitt, division chief of the Soldier Simulation Environments at the Army’s Simulation and Training Technology Center, explains that her office has challenged in-house and contract researchers to “come up with better representations of skin, bone, blood— so these wounds look right, smell right, feel right, and behave with physiological accuracy. Soldiers have to control bleeding, put a tourniquet on, and use a clotting agent if appropriate.”
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