Novice Surgeons Versus Experienced Surgeons in Laparoendoscopic SingleSite (LESS) Surgery: A Comparison of Performances in a Surgical Simulator Leonidas Alevizos, Willem Brinkman, Abe Fingerhut, Jack Jakimowicz & Emmanuel Leandros World Journal of Surgery Official Journal of the International Society of Surgery/Société Internationale de Chirurgie ISSN 0364-2313 World J Surg DOI 10.1007/s00268-012-1487-2
1 23
Your article is protected by copyright and all rights are held exclusively by Société Internationale de Chirurgie. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your work, please use the accepted author’s version for posting to your own website or your institution’s repository. You may further deposit the accepted author’s version on a funder’s repository at a funder’s request, provided it is not made publicly available until 12 months after publication.
1 23
Author's personal copy World J Surg DOI 10.1007/s00268-012-1487-2
Novice Surgeons Versus Experienced Surgeons in Laparoendoscopic Single-Site (LESS) Surgery: A Comparison of Performances in a Surgical Simulator Leonidas Alevizos • Willem Brinkman Abe Fingerhut • Jack Jakimowicz • Emmanuel Leandros
•
Ó Socie´te´ Internationale de Chirurgie 2012
Abstract Introduction During the past years, there has been increasing interest in simulation-based training of technical skills especially in laparoscopy. The purpose of this study was to compare the performances of novice and experienced laparoscopic surgeons on a LESS simulator. Methods The study recruited 20 surgeons classified into two groups: group NS consisted of ten residents without any laparoscopic experience, and group ES consisted of ten surgeons with experience in conventional laparoscopy (performed [90 laparoscopic cholecystectomies) but without any experience in LESS surgery. Both groups completed a mini-trainee course that included four repetitions of a standardized task of circle pattern cutting (CIRCLE). Time, path length, and economy of movement were measured and compared. Results Group ES presented significantly better time scores than group NS in all four repetitions. Economy of movement did not differ significantly between the two groups, whereas path length was shorter for beginners at the forth effort. Moreover, group ES failed to improve path length and economy of movement scores, whereas group
L. Alevizos (&) E. Leandros First Department of Propaedeutic Surgery, Hippokration Hospital, Athens Medical School Greece, 114 Queen’s Sofia Avenue, Athens Medical School Greece, 115 27 Athens, Greece e-mail:
[email protected];
[email protected] W. Brinkman J. Jakimowicz Department of Surgery, Catharina Hospital, Eindhoven, The Netherlands A. Fingerhut Centre Hospitalier Intercommunal, Poissy, France
NS improved their performance significantly in these parameters. Conclusions It seems that previous laparoscopic experience in conventional laparoscopy may not necessarily be an advantage in all parameters of LESS surgery and the learning process can be longer than expected even for experienced surgeons.
Introduction The evolution of surgery toward less invasive methods has led to the development of new techniques beyond conventional laparoscopic surgery, such as laparoendoscopic single-site (LESS) surgery. LESS surgery differs from conventional laparoscopy in the number of incisions to enter. In conventional laparoscopy, separate incisions are made for scope and instruments, whereas in LESS surgery a single incision is used for combined insertion of different instruments and scope [1]. Since the first report of a LESS cholecystectomy in 1997 by Navarra et al. [2], considerable interest in LESS surgery has arisen due to the potential benefits of this new technique, such as decreased postoperative pain, decreased wound complications, and better cosmetic result compared with conventional laparoscopy. As a result, there have been many reports during the past years regarding the use of LESS surgery for appendectomy, sleeve gastrectomy, adjustable gastric band, splenectomy, nephrectomy, adrenalectomy, prostatectomy, and colectomy [3–9]. Nevertheless, the advantages of LESS are mainly theoretical and have not been validated and confirmed in clinical trials. When introducing a new surgical technique, its evaluation is usually based on clinical advantage, feasibility, and patient safety. These parameters—in particular safety—are highly
123
Author's personal copy World J Surg
dependent on how easily the new technique can be learned by the average surgeon. This emphasizes the importance of thorough education and training for the operating surgeon, especially during the implementation phase of any new technique, which often is characterized by an increased rate of complications [10]. However, in the literature there are few reports on formal training in LESS surgery and especially on the use of specific LESS simulators, despite the fact that this new procedure is likely more technically challenging and associated with a significant learning curve. The purpose of this study was to compare the performances of novice and experienced laparoscopic surgeons in a LESS simulator while performing a standardized task, the circle pattern cutting (CIRCLE), and to evaluate their improvement through a series of multiple efforts. Besides, we wanted to evaluate the impact of previous conventional laparoscopic experience on the performance of surgeons during the LESS task. We hypothesized that experienced surgeons in laparoscopic surgery have a higher initial performance level and improve faster in training compared with novices in laparoscopic surgery on a LESS simulator.
Fig. 1 Screen view for the CIRCLE task
day, with 10 min intervals between efforts. Before the first effort, a detailed demonstration of the device was given and all subjects were familiarized with the system and the instruments. Equipment
Materials and methods ProMIS augmented reality simulator Subjects General surgery residents and attending surgeons were recruited. The ethical and scientific committee of our hospital approved the protocol of the study. Informed consent was given by all participants, after which they commenced the study by filling out a questionnaire about demographics and prior laparoscopic experience. Subjects were allotted to one of two groups according to their experience level. The group of novice surgeons consisted of ten general surgery residents with no previous experience in laparoscopic simulators, conventional laparoscopy, or LESS surgery (group NS). The groups of laparoscopy-experienced surgeons (group ES) consisted of ten general surgeons with laparoscopic experience ([90 laparoscopic cholecystectomies performed) but without any experience in LESS surgery. Protocol All participants completed a simulator-training program of four repetitions of the standardized task of CIRCLE. The CIRCLE consisted of an air-inflated balloon secured within a latex glove marked with a standardized double-circle target. Subjects were instructed to dissect between inner and outer circle lines without puncturing the deeper layer, using disposable laparoscopic scissors and a grasper (Fig. 1). All repetitions were performed during the same
123
The ProMIS III AR simulator consists of a torso-shaped mannequin with a neoprene cover containing an instrument tracking system. Different trays may be placed in the mannequin for each task, such as the CIRCLE task that we used in this study. On the original neoprene cover of the mannequin, a single 2.5 cm opening was made, positioned between the previous port positions, through which a LESS port (Covidien, Mansfield, MA) was secured (Fig. 2). This new port utilized one RoticulatorTM Shear and one RoticulatorTM Grasper (Covidien). Visualization was provided through another opening above the LESS port by using a 10 mm, standard-length, straight-viewing laparoscope (Karl-Storz, Tuttlingen, Germany), which was positioned in a standard location. The field of view was maintained by a study proctor manipulating the viewing angle as needed. The subjects were allowed to instruct the camera operator as needed during completion of the task. Inside the bodyform, a vision-tracking system enables tracking and measuring of the real surgical instruments within the bodyform. By marking each instrument, the vision tracking system identified the position, direction, and velocity of left instrument, right instrument, and camera at any time. The simulator presents the parameters time, path length (the cumulative distance travelled by both instruments in millimeters), and economy of movement (actual path length/ideal path length).
Author's personal copy World J Surg Table 1 Demographic characteristics of subjects NS group
ES group
Age (year)a
29 (range, 26–33)
37 (range, 32–40)
Male/female ratio
9/1
9/1
Right hand dominance
10
10
No. of laparoscopic cholecystectomies performeda
0
134 (range, 95–185)
NS novice, ES experienced surgeons a
Fig. 2 Top of Promis Augmented reality simulator modified to allow performance of LESS task
Statistical analysis Statistical analysis was performed by using SPSSÒ v17.0 (SPSS, Inc., Chicago, IL). Quantitative data were expressed as mean, median, or range. Statistical analysis was performed by using the Mann–Whitney U test to compare time, path length, economy of movement, and improvement rate between the two groups, and the v2 test (Pearson, Mantel-Haenzel test for linear association) with the Yate’s correction was used to compare the nominal characteristics of the two groups. The cutoff for statistical significance was defined as p \ 0.05.
Results Twenty subjects were enrolled in this study: ten novice surgeons (group NS) and ten experienced in laparoscopic surgery (group ES). The demographic characteristics of the participants are presented in Table 1. Time, path length, and economy of movement values for both groups are depicted in Table 2. Time scores were significantly better for group ES in all efforts (Fig. 3). Economy of movement values were better for group ES
Mean values
during the first two efforts, but group NS improved its scores from the first to the forth effort and presented better scores than group ES during the last two efforts, without reaching statistical significance (Fig. 4). Path length values were better for group ES during the first two efforts. However, group NS presented better scores during the last two efforts and this difference reached statistical significance in the last effort (p = 0.05; Fig. 5). From the first to the fourth effort, group NS presented an improvement of 32% in time scores, 54% in path length scores, and 67% in economy of movement scores. Group ES improved time scores (49%) but did not present any improvement in path length and economy of movement values. Actually, for these two parameters their scores became worse in the last effort compared with the first (Table 2). The difference in improvement between the two groups reached statistical significance for path length and economy of movement (p = 0.0001).
Discussion In this study, we showed that surgeons with previous laparoscopic experience in conventional laparoscopy do not necessarily perform better in training of LESS surgery than inexperienced surgeons without any previous laparoscopic experience. The experienced surgeons presented significantly better scores for the parameter of time, but path length, and economy of movement did not differ significantly between the two groups. Moreover, our research showed that inexperienced surgeons profited more from training in a LESS simulator than surgeons with previous experience in laparoscopic surgery, because there was a statistical difference in improvement between the two groups. In the last efforts, inexperienced surgeons reached better scores for path length and economy of movement than experienced surgeons. Traditionally, training of young surgeons was based on the Halstedian apprenticeship model ‘‘See one, Do one, Teach one,’’ which included direct observation of operations and direct practice on patients in the operating room.
123
Author's personal copy World J Surg Table 2 Comparison of time, path, and economy of movement values between novice (NS) and experienced surgeons (ES) and improvement between first and last repetition 1st effort
2nd effort
3rd effort
4th effort
Improvement
NS
401
319
241
255
32%
ES
256
146
128
119
49%
p value
0.02
0
0.01
0
1787
1168
791
186
p value
Time (s) 0.1
Path (mm) NS ES
1427
1420
1604
1800
p value
0.1
0.9
0.7
0.05
54%
0.0001
-26% Fig. 4 Comparison of path values between novice and experienced surgeons
Economy of movement NS
41
48
16
4
ES
35
28
28
40
p value
0.2
0.5
0.7
0.2
67%
0.0001
214%
Fig. 5 Comparison of and economy of movement values between novice and experienced surgeons Fig. 3 Comparison of time values between novice and experienced surgeons
Under this model, learning occurs only when the circumstances permit it, with questionable safety for the patients [11]. During the past years, the concept of ‘‘learning by doing’’ tends to become less acceptable, particularly in the surgical field, where invasive procedures are required. Surgical trainers have been prompted to look for alternative methods to teach medical knowledge and give procedural experience [12]. Fortunately, during the past ten years, there has been an explosion of the number of tools available to enhance medical education, and many training methods that simulate surgery procedures and laparoscopic operations in particular have been developed, including cadaveric animal models or anaesthetized pigs, box trainers with synthetic models, and virtual reality (VR) simulators [13]. This research was conducted with the use of a modified augmented reality simulator. This simulator and its metrics have been validated extensively and have proven to predict technical skill in laparoscopic surgery. It also provides
123
immediate psychometric data and a video record of performance on real tasks, which may be used to inform objective feedback [13]. We chose the CIRCLE task, because it has been proved to demonstrate the greatest discriminatory power between novice and experienced surgeons, possibly because of its relative complexity. It has been shown that tasks that require more advanced skills, such the CIRCLE task, have the greatest correlation with in vivo surgical performance. Although loop ligation, clip and cut, and mesh stapling are technically feasible simulator exercises, they have been shown previously to lack construct validity [14]. In the literature, there are few reports regarding formal training in LESS and especially regarding the use of specific LESS simulators, despite the fact that this new procedure appears to be more technically challenging than conventional laparoscopic surgery. Santos et al. [15] divided 27 medical students, surgical residents, and attending physicians into three groups (inexperienced, laparoscopyexperienced, and LESS-experienced) and compared the performance of standardized tasks from the Fundamentals
Author's personal copy World J Surg
of laparoscopic surgery (FLS) program, such as peg transfer, pattern cutting, placement of a ligating loop, and intracorporeal suturing, using either the standard laparoscopy technique (LAP) or the LESS technique. Overall performance of standardized tasks using a LESS port was inferior to performance using a multiport, laparoscopic technique, and surgeons with LESS experience performed better at LESS than surgeons without LESS experience. The lowest mean scores in all groups were those for peg transfer and pattern cutting, while ligating loop placement scores were more similar in LAP and LESS. This is probably due to the lateral movements that are required for the performance of the first two tasks but not for the placement of a ligating loop. The study demonstrated that using LESS techniques is more technically challenging than using LAP, even for surgeons with previous LESS experience. By contrast, our research was more focused on evaluation of the improvement of the trainees after several repetitions. In our research, group ES presented significantly better scores than group NS only for the parameter of Time. Economy of movement did not differ significantly between the two groups, but there was an obvious tendency for better scores in group NS during the two last efforts, whereas path length values were better for beginners at the forth effort. Group NS also presented higher improvement rates for the parameters of path length and economy of movement, whereas group ES achieved a higher but not significant improvement only for time and failed to improve the scores of the other two parameters examined. Possibly the experienced surgeons tended to experiment in handling the instruments or approach of the task during the repetitions they performed. This can explain the deterioration in performance on path length and economy of movement. Limitations Whereas our study gives new information concerning the performance of novice and experienced surgeons on LESS surgery, we acknowledge the fact that these findings may be limited by the use of a laboratory setting, which allowed us to perform a safe experiment with many aspects under control, and the use of a standardized task with objective performance metrics. The LESS surgery conditions in the real operating room are likely to be more difficult and the behavior and performance of surgeons can be different compared with the simulation due to factors, such as patients’ anatomy and interactions between the surgeon and his environment. Moreover, lack of familiarity with laparoscopic concept or instruments may have been a disadvantage for novice surgeons. We tried to minimize this difference by a careful
demonstration of the ProMIS III augmented reality simulator and the instruments used. Further work New research with more subjects and simulator tasks both in a LESS and conventional laparoscopic augmented reality simulator would be useful to confirm our results and better compare these two different laparoscopic approaches.
Conclusions It seems that previous laparoscopic experience in conventional laparoscopy may not necessarily be an advantage in all parameters of LESS surgery, and the learning process may be longer than expected even for experienced surgeons. Laparoscopic surgeons should be aware of the differences in techniques between LESS and conventional laparoscopy and should use a simulator, such as the ProMIS, to prepare for operating room introduction of this new technique. Acknowledgment Athens. Conflict of interest
This study was supported by University of
None.
References 1. Saber AA, El-Ghazaly TH, Dewoolkar AV (2010) Single-incision laparoscopic bariatric surgery: a comprehensive review. Surg Obes Relat Dis 6:575–582 2. Navarra G, Pozza E, Occhionorelli S et al (1997) One-wound laparoscopic cholecystectomy. Br J Surg 84:95 3. Chow A, Purkayastha S, Paraskeva P (2009) Appendicectomy and cholecystectomy using single-incision laparoscopic surgery (SILS): the first UK experience. Surg Innov 16:211–217 4. Pedersen AG, Petersen OB, Wara P et al (2001) Randomized clinical trial of laparoscopic versus open appendicectomy. Br J Surg 88:200–205 5. Teixeira J, McGill K, Binenbaum S et al (2009) Laparoscopic single-site surgery for placement of an adjustable gastric band: initial experience. Surg Endosc 23:1409–1414 6. Barbaros U, Dinccag A (2009) Single incision laparoscopic splenectomy: the first two cases. J Gastrointest Surg 13:1520–1523 7. Raman JD, Bagrodia A, Cadeddu JA (2009) Single-incision, umbilical laparoscopic versus conventional laparoscopic nephrectomy: a comparison of perioperative outcomes and short-term measures of convalescence. Eur Urol 55:1198–1204 8. Walz MK, Groeben H, Alesina PF (2010) Single-access retroperitoneoscopic adrenalectomy (SARA) versus conventional retroperitoneoscopic adrenalectomy (CORA): a case-control study. World J Surg 34:1386–1390. doi:10.1007/s00268-010-0494-4 9. Merchant AM, Lin E (2009) Single-incision laparoscopic right hemicolectomy for a colon mass. Dis Colon Rectum 52: 1021–1024
123
Author's personal copy World J Surg 10. Ritter EM, Scott DJ (2007) Design of a proficiency-based skills training curriculum for the fundamentals of laparoscopic surgery. Surg Innov 14:107–112 11. Derossis AM, Fried GM, Abrahamowicz M et al (1998) Development of a model for training and evaluation of laparoscopic skills. Am J Surg 175:482–487 12. Chung JY, Sackier JM (1998) A method of objectively evaluating improvement in laparoscopic skills. Surg Endosc 12:1111–1116 13. McCluney AL, Vassiliou MC, Kaneva PA et al (2007) FLS simulator performance predicts intraoperative laparoscopic skill. Surg Endosc 21:1991–1995
123
14. Pellen MGC, Horgan LF, Barton JR et al (2009) Construct validity of the ProMIS laparoscopic simulator. Surg Endosc 23:130–139 15. Santos BF, Enter D, Soper NJ et al (2011) Single-incision laparoscopic surgery (SILSTM) versus standard laparoscopic surgery: a comparison of performance using a surgical simulator. Surg Endosc 25:483–490
