UF Faculty Develop 'Virtual Anesthesia Machine'

GAINESVILLE, Fla.—With no zombies to shoot or planets to conquer, a new interactive computer animation developed by University of Florida researchers won’t ever take the Internet gaming world by storm. But the award-winning program is attracting a following in medical, nursing and veterinary schools around the world.

The Virtual Anesthesia Machine program, dubbed “VAM” for short, is available for free on the World Wide Web at http://www.anest.ufl.edu/vam. It simulates the inner workings of an anesthesia machine and ventilator-the complex machinery in which oxygen, nitrous oxide and anesthetics mix to render patients insensitive to pain during surgery and other procedures. The designers’ goal is to increase patient safety by arming the next generation of anesthetists with a clear understanding of the flow of gas within the equipment and the consequences of machine malfunctions or user actions on pressures, flows, and volumes and composition of gases in the anesthesia machine.

“They say a picture is worth a thousand words. We take it a step farther and postulate that an animation is worth a thousand drawings,” said Sem Lampotang, an associate professor of anesthesiology who together with Dr. Edwin Liem, David Lizdas and Walter Dobbins designed the interactive animation based on earlier work by Dr. J.S. Gravenstein, Dr. Michael Good, and Lampotang.

A 1999 Institute of Medicine report estimated that medical errors cause between 44,000 and 98,000 deaths annually in the United States. Malfunctions in the anesthesia machine and its ancillary equipment, when combined with a failure to properly check the anesthesia machine before use, may contribute to some of these medical errors. Human error and equipment malfunctions are estimated to lead to critical incidents in approximately one in 200,000 cases in which anesthesia is administered.

“Just like a pilot has to do a cockpit check before taking off, an anesthesiologist is supposed to perform a machine pre-use check before anesthetizing a patient to make sure all the components are working as they should,” said Lampotang, who is based at the Evelyn F. and William L. McKnight Brain Institute of UF.

The Food and Drug Administration recommends that such a check be conducted. “Among other learning objectives, the tutorials included in the Virtual Anesthesia Machine Web site explain the FDA pre-use check,” Lampotang said. “A better understanding of the anesthesia machine facilitates proper and expeditious execution of this check.”

At the world’s largest international scientific meeting of anesthesiologists last October, the Virtual Anesthesia Machine won the American Society of Anesthesiologists’ prize for best scientific and educational exhibit and the Anesthesia Patient Safety Foundation’s award for the best patient safety-related scientific exhibit. The VAM Web site receives thousands of visitors each month. Anesthesia instructors in New Zealand, France and many parts of the United States report they are using the program in their courses.

“I refer every resident I teach to the VAM Web site,” said Dr. G. Alec Rooke, a professor of anesthesiology at the University of Washington in Seattle. “For many years I have given residents a tutorial on the various types of gasses, but the lesson was hampered by the lack of a visual illustration of the flow of gas through the system. The Virtual Anesthesia Machine elegantly provides such visualization. The simulator clearly demonstrates the changes in gas movement during inhalation and exhalation and effectively dispels common misperceptions. It’s an incredibly useful teaching tool.”

The Virtual Anesthesia Machine depicts lungs, dials, gas canisters, pipes, ventilator settings and anesthetic agents. Color-coded circles flow through the pipes to represent molecules of oxygen, carbon dioxide, air, volatile anesthetics and nitrous oxide. Dials can be adjusted, valves opened and closed, and rates and directions of gas flow changed. Just as significantly, users are allowed to adjust the controls improperly – for example, excessively inflating the lungs – and therefore can learn from their mistakes. Equipment faults also can be simulated.

“Students have been learning how to operate an anesthesia machine by looking at static pictures in textbooks and during lectures. The crucial dimension of time is missing from these static pictures. And that’s a lot of knowing how to use the machine and timing interventions appropriately,” Lampotang said.

The Virtual Anesthesia Machine is not the first major teaching tool Lampotang has developed. He was part of the UF team that developed and refined the Human Patient Simulator over the past 15 years. The Human Patient Simulator features a lifelike, programmable mannequin that can be used to train health-care personnel how to respond to various medical emergency scenarios. Academic centers throughout the world, including UF and Santa Fe Community College in Gainesville, use the simulator to teach students.

“A major advantage of simulation is that you can focus on learning without being distracted by the concern of placing an actual patient at risk,” Lampotang said.