M.A. van Veelen

Application of ergonomic guidelines during minimally invasive surgery : A questionnaire survey of 284 surgeons

BackgroundThis study aimed to obtain an answer for the question: Are ergonomic guidelines applied in the operating room and what are the consequences?MethodsA total of 1,292 questionnaires were sent by email or handed out to surgeons and residents. The subjects worked mainly in Europe, performing laparoscopic and/or thoracoscopic procedures within the digestive, thoracic, urologic, gynecologic, and pediatric disciplines.ResultsIn response, 22% of the questionnaires were returned. Overall, the respondents reported discomfort in the neck, shoulders, and back (almost 80%). There was not one specific cause for the physical discomfort. In addition, 89% of the 284 respondents were unaware of ergonomic guidelines, although 100% stated that they find ergonomics important.ConclusionsThe lack of ergonomic guidelines awareness is a major problem that poses a tough position for ergonomics in the operating room.

Ergonomic problems encountered by the medical team related to products used for minimally invasive surgery

Background: The aim of this study is to gain insight into the problems encountered by the medical team related to products used for minimally invasive surgery.Methods: An inventory was made of the problems encountered during 12 endoscopic operations performed in one city hospital (Eindhoven, the Netherlands). After the observation, a questionnaire was distributed to all medical staff involved. Results: All categories of personnel had physical, perceptional, and cognitive problems, especially surgeons, residents, and the sterile operation nurse. The main causes were the positioning of apparatus and staff, work clothing, and the limited reach of apparatus and/or instruments. Of the questionnaires, 80% were returned: 50% of the medical staff experienced perceptional problems and 63% had physical discomfort during the surgical procedure. Conclusion: The diversity of problems observed and/or reported by the staff during minimally invasive surgery decrease the comfort, efficiency, and safety of the operating-room work environment. Therefore, a new design approach is needed for MIS products in order to address the problems that occur with the current equipment.

Improved physical ergonomics of laparoscopic surgery

One of the main and basic ergonomic problems associated with laparoscopy is the surgeons non‐neutral posture during laparoscopic procedures. There are five main issues that influence the posture of the surgeon: the (hand‐held) instrument design, the position of the monitor, the use of foot pedals to control diathermy, the poorly adjusted operating table height, and the static body posture. This paper gives an overview of the ergonomic guidelines that have been developed in these five areas and shows product solutions that have been developed according to these guidelines. The guidelines can be used by operating room (OR) staff to evaluate the ergonomics of their OR environment and to improve issues that do not satisfy the ergonomic guidelines. When designers use these guidelines to design new OR equipment, the new designs are an improvement in the field of human factors compared to the currently used laparoscopic products. When all these products are applied in the laparoscopic operating room, a new and ergonomic environment is created for the surgeon as well as for the assistants.

A newly designed ergonomic body support for surgeons.

BackgroundOne of the main ergonomic problems during surgical procedures is the surgeon’s awkward body posture, often accompanied by repetitive movements of the upper extremities, increased muscle activity, and prolonged static head and back postures. In addition, surgeons perform surgery so concentrated that they tend to neglect their posture. These observations suggest the advantage of supporting the surgeon’s body during surgical procedures. This study aimed to design a body support and to test its potential.MethodsThe optimum working condition for a surgeon is a compromise between the spine and arm positions and the level of effort and fatigue experienced performing a procedure. The design vision of the Medisign group has led to the development of an ergonomic body support for surgeons that is suitable for use during both open and minimally invasive procedures. The feasibility of the newly designed ergonomic body support was assessed during seven surgical procedures. Electromyography (EMG) was performed for back and leg muscles using the body support in an experimental setting.ResultsSix of seven participating surgeons indicated that the body support was comfortable, safe, and simple to use. The EMG results show that supporting the body is effective in reducing muscle activity. The average reduction using chest support was 44% for the erector spinae muscle, 20% for the semitendinosus muscle, and 74% for the gastrocnemius muscle. The average muscle reduction using semistanding support was 5% for the erector spinae, 12% for the semitendinosus muscle, and for 50% for the gastrocnemius muscle.ConclusionThe results of this study imply that supporting the body is an effective way to reduce muscle activity, which over the long term may reduce physical problems and discomfort. Additionally, the product supports the surgeon in his natural posture during both open and minimally invasive procedures and can easily be adapted to the current layout of the operating theater.

Evaluation of the usability of two types of image display systems, during laparoscopy

BackgroundThis study was performed to assess the optimal display location of a flat-screen monitor for laparoscopy. It was also performed to assess the posture (objective), opinion, and preference (subjective) of subjects using a flat-screen monitor positioned in the optimal display location and a cathode-ray tube monitor on a tower next to the operating table (current situation).MethodsTwelve surgeons performed cholecystectomies using the two display systems alternately. The postures of the operator and the assistant were assessed by an infrared video analysis system.ResultsThe posture of the assistant is significantly better when using a flat-screen monitor [more neutral head flexions (p=0.036) and neutral neck torsions (p=0.012)]. No significant differences were found for the posture of the operator. The operators and assistants felt more comfortable when using a flat-screen monitor (p=0.008) and they preferred this display to the use of a monitor on a tower.ConclusionsThe use of flat-screen monitors is better for the physical and psychological comfort of the users, even though the technical performance is inferior in comparison with that of regular monitors.

Improvement of foot pedals used during surgery based on new ergonomic guidelines

Background: This study aims to create new ergonomic guidelines for the design of foot pedals used during surgery. Methods: Observations in the operating room, a questionnaire among 45 laparoscopic surgeons/residents, an ergonomic literature study, and clog measurements were used to assess the problems occurring during use and to compile new guidelines for foot pedals. Based on these guidelines a new foot pedal was designed and a prototype was manufactured. Results: During the surgical procedure 91% of the subjects occasionally loses contact with the foot pedal, which 56% experience as very annoying. All subjects think that the current foot pedals obstruct their freedom of movement; 75% occasionally hit the wrong switch and 53% experience physical discomfort in their legs and/or feet. Therefore, 93% of the subjects would like to control the diathermy in a different way. The new prototype of a foot pedal was evaluated in a pilot test and proved to be ergonomically better than the currently used foot pedals. Conclusion: The new guidelines for foot pedals result in an ergonomic improvement in their design.

Improvement of the laparoscopic needle holder based on new ergonomic guidelines

Background: The aim of this study is to create new ergonomic guidelines for the design of laparoscopic needle holders. Methods: An ergonomic literature study, observations in the operating room, handle–shaft angle measurements, and anthropometric data were used to compile new ergonomic criteria, specified to the function of a laparoscopic needle holder. Based on these guidelines a new needle holder was designed. The prototype and three currently available needle holders were evaluated according to the new guidelines. In addition, a pelvi-trainer test was done to measure the extreme wrist excursions. Results: The ergonomic evaluation of three commonly used handles and the new prototype indicate that the new handle is an ergonomic improvement in the field of laparoscopic needle holders: only the new handle satisfies all criteria. This is validated by the results of the pelvi-trainer test, which showed that the new prototype significantly (p < 0.001) reduced the extreme wrist excursions. Conclusion: The new design guidelines for a laparoscopic needle holder result in an ergonomic improvement of the instrument.

Ergonomic evaluation of three new principles for mono-incision in laparoscopic surgery.

Several instruments exist for performing a simple laparoscopic procedure through one trocar‐incision. However, all of these instruments have well‐known image‐related disadvantages. In order to solve these problems three principles have been developed for which a new device was designed. The functionality of this device was evaluated with regard to four parameters: duration of task completion, number of errors, image‐stability and preference by users. Although the differences between the three principles were small, the tests clearly showed that the problems surgeons experienced before have been significantly diminished by the new device. Time measurements showed a preference for principles 1 and 2 (1: manual zoom camera in combination with a standard grasping device; 2: laparoscope with an angle of 45° in combination with a standard grasping device), the surgeons expressing preference for principle 2. Furthermore, the new trocar system is the first device for mono‐incision in which two standard instruments (currently available on the market) are used simultaneously without enlarging the incision. Finally, each surgeon can work with the new device using the principle he/she is preferring.

Development of a scheme which visualizes the human-product interaction in minimally invasive surgery

The aim of this study is to visualize in a scheme all factors that are part of or influence the human-product interaction in minimally invasive surgery (MIS). The factors involved in the interaction are identified and investigated by means of literature studies, product information from producers and retailers, and by observation of MIS procedures. An interaction scheme has been compiled which encompasses the following factors: A product factor, divided into the surgical functions of image visualization, workspace creation, tissue treatment, tissue assessment, and procedure support. A human factor, divided into the functions of perception, cognition, and action. Internal factors (perceptional, cognitive, and action) and external factors (social, political, physical, clinical, and technological) that influence the interaction. Two product examples are used to demonstrate the use of the interaction scheme. The results show that when the design of a product focuses on limited factors, problems arise related to those factors which are not considered. The interaction scheme is a new way to represent the human-product interaction in MIS. It can be used to structure and to gain insight into problems that occur with the use of MIS products. The scheme also elucidates the factors that are involved in the interaction so that they can be considered in product and operating room design.