Monitor position in laparoscopic surgery

The impact of visual scanning in the laparoscopic environment after engaging in strain coping

OBJECTIVE

We aimed to determine whether visual scanning has a detrimental impact on the monitoring of critical signals and the performance of a concurrent laparoscopic training task after participants engaged in Hockey's strain coping. Strain coping refers to straining cognitive (attentional) resources joined with latent decrements (i.e., stress).

BACKGROUND

DeLucia and Betts (2008) reported that monitoring critical signals degraded performance of a laparoscopic peg-reversal task compared with no monitoring. However, performance did not differ between displays in which critical signals were shown on split screens (less visual scanning) and separated displays (more visual scanning). We hypothesized that effects of scanning may occur after prolonged strain coping.

METHOD

Using a between-subjects design, we had undergraduates perform a laparoscopic training task that induced strain coping. Then they performed a laparoscopic peg-reversal task while monitoring critical signals with a split-screen or separated display. We administered the NASA-Task Load Index (TLX) and Dundee Stress State Questionnaire (DSSQ) to assess strain coping.

RESULTS

The TLX and DSSQ profiles indicated that participants engaged in strain coping. Monitoring critical signals resulted in slowed peg-reversal performance compared with no monitoring. Separated displays degraded critical-signal monitoring compared with split-screen displays.

CONCLUSION

After novice observers experience strain coping, visual scanning can impair the detection of critical signals.

APPLICATION

Results suggest that the design and arrangement of displays in the operating room must incorporate the attentional limitations of the surgeon. Designs that induce visual scanning may impair monitoring of critical information at least in novices. Presenting displays closely in space may be beneficial.

Ergonomic analysis of muscle activity in the forearm and back muscles during laparoscopic surgery: influence of previous experience and performed task

PURPOSE

The first aim of this study is to analyze the muscle activity in back and forearm muscles in surgeons during laparoscopic dissection and suturing maneuvers. The second aim is to determine the influence of the surgeons' previous experience in laparoscopic surgery.

METHODS

A total of 30 laparoscopic surgeons were divided in 3 groups: novice suturing, novice dissecting, and experts suturing. Electromyography data were collected from the trapezius, forearm flexors, and forearm extensors muscles, during the proposed tasks on physical simulator.

RESULTS

Muscle activity was significantly lower in the expert group. Moreover, muscle activity in the trapezius was significantly higher during the completion of intracorporeal suturing when compared with that during dissection.

CONCLUSIONS

Results obtained in this study show that the surgeons with a higher degree of laparoscopic experience exhibit a lower level of muscle activity when compared with the novice surgeons. Moreover, in accordance to our results, laparoscopic suturing involves a higher degree of muscle effort than during laparoscopic dissection.

Gaze-down endoscopic practise leads to better novice performance on gaze-up displays

OBJECTIVES

It is well known that precision skills are best learned when they are practised in the sensorimotor context that is present when performance is most important. However, a particular skill may vary with respect to the sensorimotor context in which it is performed. Certain sensorimotor variations can make a task more or less complex than others. Recent accounts of skill learning describe how task difficulty can be manipulated to provide optimised challenges to progress learners beyond their current level of expertise. This study tests the idea that simplified practise contexts lead novice learners to acquire skill proficiency that is more generalisable to new contexts.

METHODS

We present a learning experiment in which the performances of novices who acquired a set level of proficiency in the endoscopic pots-and-beans task through performance-based practise using a gaze-up endoscopic monitor arrangement were compared against the performances of novices who acquired an equivalent level of proficiency using a simplified gaze-down arrangement. Participants returned after 1 week for retention and transfer testing.

RESULTS

Time and accuracy analyses revealed that participants in both training groups improved significantly over the practise protocol and maintained this performance after a period of retention. However, the comparisons of the visual display transfer performances (i.e. on the gaze-up arrangement) of the gaze-down trainees against the retention performances (i.e. also on the gaze-up arrangement) of their gaze-up counterparts and vice versa revealed that gaze-down trainees made fewer errors in both performance contexts (F(1,16) = 7.97, p = 0.01 and F(1,16) = 57.05, p = 0.04, respectively).

CONCLUSIONS

These findings highlight the benefits associated with using simplified sensorimotor practise contexts for novice learners. Beginners will learn best from simplified practise because it allows them to develop good movement strategies for dealing with potential error without being overwhelmed by task complexity.

Effect of visual displays and locations on laparoscopic surgical training task

The number of minimally invasive surgical (MIS) procedures has substantially increased since its introduction due to health and recovery benefits for patients. However, there are potential performance issues in MIS for surgeons due to perceptual processing demands associated with supporting technologies. Monitor location has been identified as a major factor influencing performance in these types of procedures. This study examined the effect of multiple monitors on performance during a laparoscopic surgical training task (peg transfer among instruments). Twenty-four novice subjects were exposed to different monitor conditions including a default position, a biomechanically compatible position, and a position collocated with the operating surface as well as the combination of the latter two. Subjective rankings and cognitive workload were also assessed. Results revealed a significant effect of monitor position on task time when compared to subjects' baseline training task time using the default monitor setup. Collocating the monitor with the operating surface was shown to be superior in terms of task time. There were no significant differences among monitor positions in terms of perceived workload. The results of this study provide an applicable guide for the design of MIS setups in the operating room to promote surgeon performance.

Ergonomic factors on task performance in laparoscopic surgery training

This paper evaluates the effect of ergonomic factors on task performance and trainee posture during laparoscopic surgery training. Twenty subjects without laparoscopic experience were allotted into 2 groups. Group 1 was trained under the optimal ergonomic simulation setting according to current ergonomic guidelines (Condition A). Group 2 was trained under non-optimal ergonomic simulation setting that can often be observed during training in a skills lab (Condition B). Posture analysis showed that the subjects held a much more neutral posture under Condition A than under Condition B (p<0.001). The subjects had less joint excursion and experienced less discomfort in their neck, shoulders, and arms under Condition A. Significant difference in task performance between Conditions A and B (p<0.05) was found. This study shows that the optimal ergonomic simulation setting leads to better task performance. In addition, no significant differences of task performance, for Groups 1 and 2 using the same test setting were found. However, better performance was observed for Group 1. It can be concluded that the optimal and non-optimal training setting have different learning effects on trainees' skill learning.

[Ergonomics in laparoscopic surgery and its importance in surgical training]

Despite the many advantages that laparoscopic surgery has for patients, it involves a series of risks for the surgeon. These are related to the reduced freedom of movement and forced postures which lead to greater muscle fatigue than with conventional surgery. In laparoscopic surgery there are few references on the introduction of training programs in ergonomics, despite the numerous advantages demonstrated in other disciplines. The application of ergonomic criteria in the surgical field could have great benefits, both for surgeons and patients. In this work we attempt to review the existing literature and our experience to provide the surgeon with some ergonomic guidelines for body stance and positioning of equipment. We also present a training model based on ergonomics which we have introduced into the training activities carried out in our Centre.

Psychological and physical stress in surgeons operating in a standard or modern operating room

PURPOSE

There have been no studies examining the effect of optimized ergonomic and technical environment on the psychological and physiological stress of the surgeon. The aim of this study was to examine whether optimized ergonomics and technical aids within a modern operating room (OR) affect psychological and physiological stress in experienced laparoscopic surgeons.

METHODS

This was a prospective case-controlled study including 10 experienced surgeons. Surgery was performed in 2 different ORs: a standard room and a modern room (OR1-suite, Karl Storz). The surgeons filled out questionnaires concerning physical and psychological wellbeing before and after surgery and had their heart rate variability registered during surgery.

RESULTS

Preoperative to postoperative physical strain and pain measurements revealed a systematical difference with 14 of 15 parameters favoring the modern OR. Two of these parameters reached statistical significance. We did not find any significant differences in the subjective parameters of surgeon satisfaction or the measured heart rate variability parameters.

CONCLUSIONS

Physical strain on the surgeon was reduced when performing laparoscopic cholecystectomy in a modern OR compared with a standard room.

Ergonomic assessment of the posture of surgeons performing endoscopic transurethral resections in urology

Background

During transurethral endoscopic prostate and bladder operations the influence of an ergonomic redesign of the arrangement of the operation equipment - including the introduction of a video-assisted resection method ('monitor endoscopy') instead of directly viewing onto the operation area via the endoscope ('direct endoscopy') - was studied with respect to the postures of the surgeons.

Methods

Postures were analysed on the basis of video recordings of the surgeons performed in the operation theatre during live operations and subsequent visual posture estimation executed by an observer. In particular, head, trunk and arm positions were assigned to posture categories according to a newly developed posture classification schema. 10 urological operations with direct endoscopy and 9 with monitor endoscopy were included.

Results

Application of direct endoscopy coincides with distinct lateral and sagittal trunk and head inclinations, trunk torsion and strong forearm and upper arm elevations of the surgeons whereas operations with monitor endoscopy were performed with an almost upright head and trunk and hanging arms. The disadvantageous postures observed during direct endoscopy are mainly caused by the necessity to hold the endoscope continuously in close contact with the eye.

Conclusion

From an ergonomic point of view, application of the video-assisted resection method should be preferred in transurethral endoscopic operations in order to prevent awkward postures of the surgeons and to limit muscular strain and fatigue. Furthermore, the application of the monitor method enables the use of a chair equipped with back support and armrests and benefits the reduction of postural stress.

Optimal ergonomics for laparoscopic surgery in minimally invasive surgery suites: a review and guidelines

BACKGROUND

With minimally invasive surgery (MIS), a man-machine environment was brought into the operating room, which created mental and physical challenges for the operating team. The science of ergonomics analyzes these challenges and formulates guidelines for creating a work environment that is safe and comfortable for its operators while effectiveness and efficiency of the process are maintained. This review aimed to formulate the ergonomic challenges related to monitor positioning in MIS. Background and guidelines are formulated for optimal ergonomic monitor positioning within the possibilities of the modern MIS suite, using multiple monitors suspended from the ceiling.

METHODS

All evidence-based experimental ergonomic studies conducted in the fields of laparoscopic surgery and applied ergonomics for other professions working with a display were identified by PubMed searches and selected for quality and applicability. Data from ergonomic studies were evaluated in terms of effectiveness and efficiency as well as comfort and safety aspects. Recommendations for individual monitor positioning are formulated to create a personal balance between these two ergonomic aspects.

RESULTS

Misalignment in the eye-hand-target axis because of limited freedom in monitor positioning is recognized as an important ergonomic drawback during MIS. Realignment of the eye-hand-target axis improves personal values of comfort and safety as well as procedural values of effectiveness and efficiency.

CONCLUSIONS

Monitor position is an important ergonomic factor during MIS. In the horizontal plain, the monitor should be straight in front of each person and aligned with the forearm-instrument motor axis to avoid axial rotation of the spine. In the sagittal plain, the monitor should be positioned lower than eye level to avoid neck extension.

Ergonomic assessment of neck posture in the minimally invasive surgery suite during laparoscopic cholecystectomy

BACKGROUND

With the expanding implementation of minimally invasive surgery, the operating team is confronted with challenges in the field of ergonomics. Visual feedback is derived from a monitor placed outside the operating field. This crossover trial was conducted to evaluate and compare neck posture in relation to monitor position in a dedicated minimally invasive surgery (MIS) suite and a conventional operating room.

METHODS

Assessment of the neck was conducted for 16 surgeons, assisting surgeons, and scrub nurses performing a laparoscopic cholecystectomy in both types of operating room. Flexion and rotation of the cervical spine were measured intraoperatively using a video analysis system. A two-question visual analog scale (VAS) questionnaire was used to evaluate posture in relation to the monitor position.

RESULTS

Neck rotation was significantly reduced in the MIS suite for the surgeon (p = 0.018) and the assisting surgeon (p < 0.001). Neck flexion was significantly improved in the MIS suite for the surgeon (p < 0.001) and the scrub nurse (p = 0.018). On the questionnaire, the operating room team scored their posture significantly higher in the MIS suite and also indicated fewer musculoskeletal complaints.

CONCLUSIONS

The ergonomic quality of the neck posture is significantly improved in the MIS suite for the entire operating room team.

Ergonomic problems encountered by the surgical team during video endoscopic surgery

BACKGROUND

The aim of this study is to analyze the problems related to the ergonomic conditions faced by video endoscopic surgical teams during video endoscopic surgery by means of a questionnaire.

METHODS

A questionnaire was distributed to 100 medical personnel, from 8 different disciplines, who performed video endoscopic surgeries. Participants were asked to answer 13 questions related to physical, perceptive, and cognitive problems.

RESULTS

Eighty-two questionnaires were returned. Although there were differences among the disciplines, participants assessment of various problems ranged from 32% to 72% owing to poor ergonomic conditions.

CONCLUSIONS

As the problems encountered by the staff during video endoscopic surgery and the poor ergonomic conditions of the operating room affect the productivity of the surgical team and the safety and efficiency of the surgery, redesigning of the instruments and the operating room is required.

Safety, hazards and ergonomics in the operating room

OBJECTIVE

The objective for this study was to address the lack of information regarding the working conditions in the operating room (OR). Safety issues in the OR need to be discussed not only for the sake of patients, but also for personnel, as hazards may occur for all persons within the OR.

METHODS

To evaluate the workplace conditions in the operating room, a survey was conducted among surgeons working in German hospitals. Sixty questions were asked regarding the personal profile, the architectural situation, the devices and instruments as well as working posture and associated pain.

RESULTS

The survey showed elementary ergonomic deficiencies within all fields. Surgeons stated that these deficiencies lead to potential hazards for patients and personnel, potentially on a frequent basis. 97% of the surveyed surgeons see ergonomic improvement in the operating room as necessary.

CONCLUSION

The survey results display a high potential for improvement within all fields. Therefore, industry, surgeons and their professional organizations are asked to work on the optimization of the workplace conditions in the operating room in terms of improvement of quality and efficiency.

Safety, hazards and ergonomics in the operating room

OBJECTIVE

The objective for this study was to address the lack of information regarding the working conditions in the operating room (OR). Safety issues in the OR need to be discussed not only for the sake of patients, but also for personnel, as hazards may occur for all persons within the OR.

METHODS

To evaluate the workplace conditions in the operating room, a survey was conducted among surgeons working in German hospitals. Sixty questions were asked regarding the personal profile, the architectural situation, the devices and instruments as well as working posture and associated pain.

RESULTS

The survey showed elementary ergonomic deficiencies within all fields. Surgeons stated that these deficiencies lead to potential hazards for patients and personnel, potentially on a frequent basis. 97% of the surveyed surgeons see ergonomic improvement in the operating room as necessary.

CONCLUSION

The survey results display a high potential for improvement within all fields. Therefore, industry, surgeons and their professional organizations are asked to work on the optimization of the workplace conditions in the operating room in terms of improvement of quality and efficiency.

Ergonomics with the use of curved versus straight laparoscopic graspers during rectosigmoid resection: results of a multiprofile comparative study

BACKGROUND

A detailed ergonomic comparison of motions and muscular activity in the left upper extremity using a laparoscopic straight or curved grasper in rectosigmoid resection is presented.

METHODS

The study had two parts: experimental and clinical. In the experiment part, 30 laparoscopic sigmoid resections were performed under animal organ phantom conditions. The operations were divided into three groups according to instrument and trocar position. Group 1 (n = 10) underwent operations performed with a curved grasper in the excentral trocar position (in relation to the telescope trocar), with the left-hand curved grasper placed in the right flank and the right hand instrument in the right lower quadrant. In group 2 (n = 10), straight forceps were used in the excentral trocar position. Group 3 (n = 10) underwent laparoscopic sigmoid resection performed with a straight grasper in the central position (in relation to the telescope trocar), with the instruments placed at both sides of the lower abdomen. To measure ergonomic aspects during rectosigmoid resection, several overview video cameras, surface electromyography (EMG), an ultrasound tracking system (UTS), and a questionnaire were used. In the clinical part of the study, laparoscopic rectosigmoid resections (n = 5) were performed using a curved instrument in the excentral trocar position. The surgeon's left-hand movement and body posture were recorded for further analysis.

RESULTS

The curved grasper required the fewest contractions (group 1) of the measured muscles. A comparison of the UTS analysis in the experimental part of the study and the video analysis in the clinical part showed economy of movements in group 1. According to subjective estimation, both physical activity and mental stress remain at the lowest level when the excentral trocar position is used (groups 1 and 2).

CONCLUSIONS

The combination of the curved grasper and the excentral trocar position (in relation to the telescope trocar) is, according to our examinations, the best ergonomic adjustment for laparoscopic rectosigmoid surgery.

Optimizing laparoscopic task efficiency: the role of camera and monitor positions

BACKGROUND

Alterations of video monitor and laparoscopic camera position may create perceptual distortion of the operative field, possibly leading to decreased laparoscopic efficiency. We aimed to determine the influence of monitor/camera position on the laparoscopic performance of surgeons of varying skill levels.

METHODS

Twelve experienced and 12 novice participants performed a one-handed task with their dominant hand in a modified laparoscopic trainer. Initially, the camera was fixed directly in front of the participant (0 degrees) and the monitor location was varied between three positions, to the left of midline (120 degrees), directly across from the participant (180 degrees), and to the right of the midline (240 degrees). In the second experiment monitor position was constant straight across from the participant (180 degrees) while the camera position was adjusted between the center position (0 degrees), to the left of midline (60 degrees), and to the right of midline (300 degrees). Participants completed five trials in each monitor/camera setting. The significance of the effects of skill level and combinations of camera and monitor angle were evaluated by analysis of variance (ANOVA) for repeated measures using restricted maximum likelihood estimation.

RESULTS

Experienced surgeons completed the task significantly faster at all monitor/camera positions. The best performance in both groups was observed when the monitor and camera were located at 180 degrees and 0 degrees, respectively. Monitor positioning to the right of midline (240 degrees) resulted in significantly worse performance compared to 180 degrees for both experienced and novice surgeons. Compared to 0 degrees (center), camera position to the left or the right resulted in significantly prolonged task times for both groups. Novice subjects also demonstrated a significantly lower ability to adjust to suboptimal camera/monitor positions.

CONCLUSION

Experienced subjects demonstrated superior performance under all study conditions. Optimally, the camera should be directly in front and the monitor should be directly across from a surgeon. Alternatively, the monitor/camera could be placed opposite to the surgeon's non-dominant hand. The suboptimal camera/monitor conditions are especially difficult to overcome for inexperienced subjects. Monitor and camera positioning must be emphasized to ensure optimal laparoscopic performance.

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

BACKGROUND

This study aimed to obtain an answer for the question: Are ergonomic guidelines applied in the operating room and what are the consequences?

METHODS

A 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.

RESULTS

In 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.

CONCLUSIONS

The lack of ergonomic guidelines awareness is a major problem that poses a tough position for ergonomics in the operating room.

Screen height as an ergonomic factor in laparoscopic surgery

BACKGROUND

The increasing number of routinely performed laparoscopic operations causes the surgeons' "screen work" time to rise constantly. A new ergonomic workload on the surgeons' upper spine and shoulders is created as a result of the standard screen height position on top of the laparoscopy towers.

METHODS

Eight surgeons in the authors' surgical department were evaluated for the inclination/reclination angle of their cervical spine when using the laparoscopy towers in the authors' department and also at their favorable screen height.

RESULTS

The laparoscopy towers used in the authors' department made 3 degrees to 14 degrees reclination of the cervical spine necessary. The interviewed surgeons preferred a position of slight inclination, with a median of 160 cm measured from the central screen height to the floor.

CONCLUSION

Monitors of laparoscopy towers should be adapted to the surgeon's preferred screen height: at eye level frontally with a neutral or slight inclination of the cervical spine. The authors suggest a central screen height of 160 cm, with the monitor positioned in front of the surgeon. Newer equipment from the industry should be provided.

Ergonomic testing of two different types of handles via virtual reality simulation

BACKGROUND

Ergonomics in laparoscopic surgery is an unsolved problem. Deficiencies of the instrument handles are well-known and described in several reports and studies. Today, virtual training modules for laparoscopic surgery are available. The aim of this study was to evaluate the ability of a virtual reality (VR) simulator to determine the ergonomic properties of two different laparoscopic instrument handles.

METHODS

Two different types of handles, a ring and an axial handle from Richard Wolf, were used to perform the short clip and cut task of the Xitact 500 LS simulator. The task was repeated every 2 days for a period of 5 weeks. After every trial the volunteers were asked structured questions about their preferences while using the two handles.

RESULTS

The axial handle was superior or equal to the ring handle in all criteria. Learning curves over the entire time and day by day were similar. No differences were found for travel distances and error rates, but task times were different for both handles. The subjects preferred the axial handle at the end of the study.

CONCLUSION

It is possible to determine differences in ergonomics of handle design with a VR trainer. In this study, the Richard Wolf axial handle was superior to the ring handle.