Ergonomics in the Operating Room Ramon Berguer, MD, Martinez, California

(The surgeon) . . is the most interesting of all me- chanics; the motions that he m&s being the most delicate, the most important, and the most far- reaching in their importance.

Frank B. Gilbreth, 1916

A surgeon’s work is carried out in a specialized work environment, the design of which can be as impor- tant to the critical task at hand as is a pilot’s cock-

pit. Ergonomic studies of the workplace in fields other than medicine have demonstrated the link between workplace de- sign and operator performance and injury.’ It is therefore surprising that a review of the medical, engineering, gov- ernment, and military literature reveals very few systematic studies of a surgeon’s work environment and tools.z-4 Indeed there are more published studies about optimizing the work environment of a pilot,5,6 an industrial welder,7 or a com- puter terminal operator* than can be found about the oper- ating room. If we are to become efficient, successful, and cost-effective 21st Century surgeons, we must seriously con- sider how our performance is affected by the design of our environment and tools.’

The idea of improving operating room efficiency through the use of ergonomic studies is not new.*O Frank B. Gilbreth, whose pioneering early 20th Century time-motion studies of bricklayers demonstrated the usefulness of workplace ergo- nomic analyses, ” studied surgeons working in hospitals na- tionwide and concluded in 1916 that “. . surgeons could learn more about motion study, time study, waste elimina- tion, and scientific management from the industries than the industries could learn from the hospitals.“‘* Sixty years later, Dudley13 addressed the issue of efficiency in the operating room and concluded again that “Looked at from the ergo- nomic point of view most major operations are, at first sight, a mess.” Since that time, a number of authors have suggested ways to improve the design and efficiency of the surgeon’s workplace and instruments based on general ergonomic prin- ciples,‘“J4J5 but their ideas have not yet undergone objec- tive testing. Thus, although surgeons have been interested in ergonomic principles in their work, there are very little scientific data in this area.

Am J Surg. 1996;171:385-366. From the University of California Davis, Martinez, California. Requests for reprints should be addressed to Ramon Berguer,

MD, 150 Muir Road (112), Martinez, California 94553. Manuscript submitted April 3, 1995 and accepted in revised form

September 5, 1995.

Surgeons are trained under the impression that modem surgery has evolved out of sheer practicality into a reason- ably efficient task-one that is unlikely to be greatly im- proved by ergonomic scrutiny. Through years of training we learn to adapt to the physical demands of open surgery and successfully perform a wide range of complex operations. Yet, who amongst us has not repeatedly wished for improved re- traction, better lighting, a more suitable instrument, or even a chair to sit on during a difficult operation? Even the com- monplace arrangement of the scrub nurse and the surgeon, refined by repeated use over the past century,i3J5 does not appear to have been objectively studied and may be in need of review in laparoscopic operations.i6 Advances in mini- mally invasive surgery are rapidly changing s.urgical tech- niques and posing even greater ergonomic challenges to the surgeon and the operating room environment. Very recent studies confirm that minimally invasive procedures impose significant and previously unknown constraints on the sur- geon’s movements and posture,17 tactile feedback and force transmission,18 and visual perception. l9 The additional equip- ment, cables, and tubes needed for modem operations add to the already crowded operating room environment2” and can overwhelm available equipment storage areas. These and other factors make ergonomic studies in open and minimally invasive surgery seem desirable.

Ergonomic studies in other fields clearly demonstrate di- minished performance and an increase in fatigue and error rates in subjects exposed to suboptimal or “overloaded” er- gonomic conditions. 21 If we extrapolate these finding to the operating room environment, we might expect to find that when our instruments, equipment, or work environment are suboptimally designed the performance of the entire surgi- cal team is impaired. i5 Under these conditions, inefficiency and fatigue may contribute to increased operating room costs, personnel injury, and possibly technical errors.22,23 In minimally invasive surgery, an unstudied approach to the operating room environment will certainly magnify the sur- geon’s sensory and motor limitations and may make it more difficult to integrate future technologies, such as head- mounted displays, 3-dimensional anatomic pmjections, ro- botic assistants, and teleoperation into our daily surgical practice. It therefore seems pressing for financial, occupa- tional, technical, and, ultimately, clinical reasons that we should not allow surgeons to become further encumbered by the ergonomic limitations of their workspace and tools.

We must seek solutions to the problems of exposure, fa- tigue, efficiency, and cost in the operating room through a systematic analysis of surgical operations and the applica- tion of well-founded ergonomic principles. Surgeons and operating room personnel should make an effort to work with their engineering schools and others to .bring our en-

THE AMERICAN JOURNAL OF SURGERY” VOLUME 171 APRIL 1996 385

vironments and tools up to the best theoretical and practi- cal standards. To accomplish this goal, “surgical ergonom- ics” should become an accepted field for academic re- search.24 The small number of ergonomic studies referenced above represent an embryonic effort to understand our work environment in the era of minimally invasive surgery. More studies are needed in open and endoscopic surgery to eval- uate key factors such as optimum room and personnel lay- out, visual display positioning, equipment integration, in- strument design, and numerous other factors that affect a surgeon’s work. In developing specific ergonomic standards for the operating room, we must depart from the current concept of the operating room as a “shell” into which peo- ple and devices are placed. Instead, the operating room of the future must be conceived from the beginning around the task at hand and integrate electrical power, medical gases, communication, video, data display, and other neces- sities in such a way that they enhance-not interfere with- the work of the surgical team.15 We need to establish er- gonomic standards for surgical equipment to ensure smooth integration into this new operating room environment via built-in ceiling or wall-mounted systems.26 Instrument de- sign-particularly in minimally invasive surgery-must place greater emphasis on the biomechanics of the human interfacez7 and how the instrument is manipulated in a real surgical environment so that the surgeon can work in the most natural way possible. Lastly, we must insist on spend- ing the time and money necessary to make these changes in our operating rooms if we wish to improve our perfor- mance and extend the range of open and minimally inva- sive surgery to our patients’ benefit.

Nearly 80 years ago, Gilbreth’* appealed to surgeons to take a proactive stance toward better workplace and instrument design, and the significance of his observations still rings true today: “The product which (the surgeon) handles is the most valuable, his own attitude and that of all concerned has the most effect upon the outcome, and the effect of any changes made is the most deeply and widely felt.”

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