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| From Technology Review, January 1995 A Cure for Surgical Chaos . . . . . . . . . . . . . By David Brittan THE FIRST TIME Kenneth Kaplan walked into a typical hospital operating room, he was alarmed by the working conditions. Tangled wiring, unvented smoke, stacks of monitors held together with masking tape, people tripping over cords. ''It's quite a hostile environment,'' he concluded. Today Kaplan, an architect with a joint appointment in MIT's Department of Architecture and Research Laboratory of Electronics, is coordinating an ambitious five-year program sponsored by the Advanced Research Projects Agency (ARPA) to redesign the often chaotic surgical environment. What began as a project aimed at saving lives on the battlefield has broadened into an effort to create the ''operating room of the future,'' a compact and efficient unit that can gradually incorporate tomorrow's surgical technology without turning into a jumble of incompatible equipment. Kaplan's involvement in the project began two years ago, when Col. Richard Satava, an Army surgeon and manager of ARPA's Advanced Biomedical Technology Program, asked him to figure out how to fit high-tech surgical equipment into military ambulances. Satava's scheme was, and still is, mind-boggling. The plan is to develop telerobotic technology that will enable surgeons at field hospitals to perform emergency procedures on wounded soldiers as they are being evacuated. In the ambulance, a bank of instruments will cut, laser, and suture, all under the control of the distant surgeon, who will view the procedure through a head-mounted display. The surgeon will manipulate a set of tools wired to a computer that senses every gesture and instructs the remote surgical tools to move accordingly. ARPA has already demonstrated a crude mockup in which a prototype telerobotic apparatus was used to truss assorted chicken parts. In keeping with its much heralded commitment to dual use, the agency also envisions a civilian version of the system. ''After all,'' says Kaplan, ''the statistics are that it's more dangerous to be in the streets of Los Angeles than in Somalia.'' Ambulances equipped for telerobotic surgery could help accident or gunshot victims survive the trip to the hospital. But a major obstacle, as Kaplan soon learned after accepting Satava's challenge, is equipping the hospitals where telerobotic surgeons will be based. ''The standard operating room is a mess,'' he says. ''The technology infusion into it is uncontrolled, and there's no room for yet another big, complex system.'' Kaplan quickly realized that ORs need an overhaul whether they are used for remote surgery or not. So while other participants in the ARPA project—such as Ian Hunter, an associate professor in MIT's Department of Mechanical Engineering—pursue telerobotic surgical systems, Kaplan is starting design work on an operating room that will accept such new technologies smoothly and seamlessly. The guinea pig in Kaplan's experiment is Massachusetts General Hospital (MGH) in Boston, which has agreed to test a prototype OR. Within three to four years, he says, MGH will host a new ''modular'' surgical unit that Kaplan compares to the Nikon camera system: ''You buy the body and add on the lenses you want.'' Once surgeons have tested it at MGH, the unit will be manufactured and sold as a kit of parts that can be configured according to a hospital's needs. The surgical unit Kaplan envisions will be portable enough that it could fit into an existing room at a civilian hospital or be adapted to military trucks, helicopters, submarines, or tents. What ts. What willl the surgical room of the future be like? For starters, it will incorporate Kaplan's favorite design principle: integration. ''A hospital is really layers and layers of unintegrated systems on top of each other,'' he says. A major symptom of this condition is the proliferation of specialized operating rooms. ''Every time a new procedure is invented,'' says Kaplan, ''a hospital has to build another OR.'' MGH, for example, has 45 different operating rooms, each devoted to a surgical specialty. Kaplan wants to ''create one OR in which 45 different procedures can occur.'' To smooth the integration process, ARPA has enlisted the aid of Northrop-Grumman, the newly formed union of two aerospace companies that have considerable experience in tying together components from different sources. Northrop-Grumman's B-2 stealth bomber, says Kaplan, contains more computer systems than the space shuttle. ''The B-2 people act as `general contractors,' and if you want your equipment to go into their cockpit, you had better conform to their specs,'' he says. This approach enables aircraft builders to upgrade their planes by plugging in modular equipment instead of redesigning the cockpit. But medical equipment suppliers ''have never been forced to work together the way aerospace companies have,'' says Kaplan. ''Aerospace people who've looked at surgical rooms say these rooms are now where cockpits were 30 or 40 years ago.'' One of Northrop-Grumman's tasks will be to develop ''generic specs'' to ensure that equipment for the new surgical room is compatible and easily updated. Kaplan also hopes to solve some nagging ergonomic issues that hospitals have never fully addressed. ''For example,'' he says, ''the problems of lighting are quite dramatic.'' Surgeons need intense task lighting for cutting tissue, says Kaplan, but their approach has been to use crude clamp lamps that reflect off tissue and cast shadows, with the unpleasant result that ''the surgeon has to reach out with a bloody hand and adjust the light.'' Expect to see robotic lighting systems that respond to the surgeon's voice, hand gestures, or eye blinks. Another area begging for reform is the visual display of information. Today's racks of monitors are often widely separated and hard to see, says Kaplan. ''The surgeon has to ask the anesthesiologist for a readout, and often must crane to view TV monitors displaying medical imaging.'' Kaplan would bring even more information into the operating room—patient records and textbook excerpts, for example—but display it in a more accessible way. He's looking into providing large screens that have multiple windows, equipping surgeons with head-mounted displays, or even embedding display screens into the operating table. And while he's on the topic of tables, Kaplan has a few grievances that he'd like to redress. ''There's all this stuff underneath. There's no place to put your feet. There's no place to sit. The table has never been designed—it just sort of exists.'' Using composite materials would make the surgical table lighter and more flexible, he says, and padding the surface with electrorheological fluid—material that changes from liquid to solid with an electric current—would allow the table to conform better to the patient's body. In fact, Kaplan is thinking these days, why not go all the way and equip surgical tables with telecommunications so patients can receive words of reassurance from loved ones while waiting to go in for surgery? Reach Out and Stitch Someone As telerobotic surgical technology matures, the operating room will be transformed further still. This part of the equation is the province of mechanical-engineering professor Ian Hunter, whose laboratory is designing computer-based ''virtual environments'' that will give tomorrow's surgeons unparalleled control over their instruments. Hunter's virtual environments are digitized maps of the body part on which the surgery is to be performed. They include not only visual data—allowing the physician to view the surgery on a computer monitor from any angle or distance—but also data on the mechanical properties of the tissues being operated on. Seated in front of a monitor, the surgeon will manipulate a ''master'' unit, a set of tools that translate hand motions produced on a human scale into exquisitely fine gestures (a thousandth or even a millionth the size of the original) executed by a robot ''slave'' unit above the patient. Thanks to the tissue-mechanics data stored in the virtual environment, the master instruments will provide ''force feedback''—a physical sensation of resistance that helps the surgeon gauge how hard to press. Hunter's group has built a prototype virtual environment for eye surgery and is working on another one for the heart. Although Hunter's immediate aim is to enhance surgery where practitioner and patient are both in the same room, he says it is only a matter of time before telerobotic surgery becomes feasible over long distances. His wife, Lynette Jones, a principal research scientist in the Department of Mechanical Engineering, is studying the effect of delays in visual and force feedback—an irksome artifact of telecommunications—on a surgeon's ability to operate. She says it may be possible to compensate for time lags with software that predicts changes in the mechanical properties of tissues as the surgeon cuts. Even before they find their way into the surgical room of the future, however, virtual environments will play a crucial role in the room's design. ''The same tools that you use to create virtual environments of organs can be used to create virtual environments of operating rooms,'' says Hunter. For example, the lasers that rapidly scan a patient's body to determine its geometry can just as easily scan a room and its contents and feed the measurements into a computer so designers can begin moving things around on screen. Kaplan is working with Hunter and with Nathaniel I. Durlach, a senior research scientist in MIT's Department of Electrical Engineering and Computer Science, to develop a virtual environment where prospective users can sit before a computer display of a surgical room and adjust conditions such as lighting and airflow, manipulate surgical tools, and generally get a feel for the layout. Over the next five years, the researchers expect to generate dozens of possible room designs tailored for different settings. Kaplan recognizes the dangers of dispensing high-tech solutions in a milieu that is often accused of being too quick to adopt expensive cutting-edge technologies. But his defense is simple: a well-designed, well-integrated surgical room can save hospitals money. In today's haphazard approach to surgical facilities, he explains, ''a doctor comes along and says, `Hey, I've got a great idea,' the hospital buys a new system, they put it in the room, it doesn't work, they put it over to the side, and then they come in with another system. We're offering to gate-keep these technologies.'' The virtual-environment design tool, he says, will also allow hospitals to avoid costly mistakes at the planning stage. db |