Abstrakt Ostatní Únor 2010

“The impact of stress on surgical performance: A systematic review of the literature.”

Arora, S., N. Sevdalis, et al. (2010).

Surgery 147(3).


Background: Safe surgical practice requires a combination of technical and nontechnical abilities. Both sets of skills can be impaired by intra-operative stress, compromising performance and patient safety. This systematic review aims to assess the effects of intra-operative stress on surgical performance. Methods: A systematic search strategy was implemented to obtain relevant articles. MEDLINE, EMBASE, and PsycINFO databases were searched, and 3,547 abstracts were identified. After application of limits, 660 abstracts were retrieved for subsequent evaluation. Studies were included on the basis of predetermined inclusion criteria and independent assessment by 2 reviewers. Results: In all, 22 articles formed the evidence base for this review. Key stressors included laparoscopic surgery (7 studies), bleeding (4 studies), distractions (4 studies), time pressure (3 studies), procedural complexity (3 studies), and equipment problems (2 studies). The methods for assessing stress and performance varied greatly across studies, rendering cross-study comparisons difficult. With only 7 studies assessing stress and surgical performance concurrently, establishing a direct link was challenging. Despite this shortfall, the direction of the evidence suggested that excessive stress impairs performance. Specifically, laparoscopic procedures trigger greater stress levels and poorer technical performance (3 studies), and expert surgeons experience less stress and less impaired performance compared with juniors (2 studies). Finally, 3 studies suggest that stressful crises impair surgeons’ nontechnical skills (eg, communication and decision making). Conclusion: Surgeons are subject to many intra-operative stressors that can impair their performance. Current evidence is characterized by marked heterogeneity of research designs and variable study quality. Further research on stress and performance is required so that surgical training and clinical excellence can flourish. © 2010 Mosby, Inc. All rights reserved.




“An ex-vivo evaluation of the application and strength of a novel laparoscopic knot substitute device.”

Chi, T., B. H. Eisner, et al. (2010).

Journal of Endourology 24(1): 95-98.


Background and Purpose: Intracorporeal suturing can be challenging, especially in the case of laparoscopic partial nephrectomy. During these procedures, suturing must reapproximate renal tissue to achieve hemostasis but not tear through tissue. We present a new device, the ANPA Suturelock <sup>®</sup>, which can be adjusted to increase or decrease suture tension, optimizing tissue apposition. Materials and Methods: Two participants (one experienced laparoscopist, one junior resident) completed the protocol. A laparoscopic trainer was used to secure 2-0 polyglactin suture ends in rubber foam using five of each of the following: Traditional laparoscopic suture knots (one surgeon’s knot and two square knots), square-to-slip knots, Weston extracorporeal knots, ANPA Suturelock, Lapra-Ty devices, Hem-O-Lock clips, and titanium clips. Tensile strength of each knot and knot substitute was measured using an Instron machine (Instron, Norwood, MA). Time to secure the two suture ends was measured for ANPA Suturelock and laparoscopic surgeon’s knot. Statistical analysis was performed using the Student t test. Results: Mean tensile strength of the three knot-tying methods was 53.0 newtons (N) while that of the four knot substitute devices was 8.3 N (P &lt; 0.001). Each of the three individual knot-tying methods had significantly greater tensile strength than any of the knot substitutes (P &lt; 0.001 for all). Of the knot-tying methods, the surgeon’s knot was the strongest (mean tensile strength 63.2 N) and was significantly stronger than square-to-slip and Weston extracorporeal knots (39.1 N and 48.4 N, respectively, P &lt; 0.05 for both). Of the knot substitutes, ANPA Suturelock (mean tensile strength 14.7 N) was significantly stronger than Lapra-Ty (6.1 N), Hem-O-Lock (5.4 N), and titanium clip (3.0 N) (P &lt; 0.01 for all). When compared with a laparoscopic surgeon’s knot, the time to securing the ANPA Suturelock was significantly quicker for a third year resident (106 sec vs 38 sec, P &lt; 0.001) and an experienced laparoscopist (75 sec vs 23 sec, P = 0.02). Conclusions: The tensile strengths of traditional knot-tying techniques were greater than that of any knot substitute device. The ANPA Suturelock provided the greatest tensile strength of any knot substitute. The time to secure a knot using the ANPA device was also significantly quicker than tying a standard surgeon’s knot. © Mary Ann Liebert, Inc. 2010.


“Robotic and navigational technologies in endovascular surgery.”

De Marco, A. N., C. V. Riga, et al. (2010).

Vascular Disease Management 7(1).




“The Modified Clavien System: A Plea for a Standardized Reporting System for Surgical Complications.”

Graefen, M. (2010).

European Urology 57(3): 387-389.




“Instrumentation for Robotic Surgery.”

Hensell, M. G. (2010).

Perioperative Nursing Clinics 5(1): 69-81.


Robotic surgery is performed with a computerized system that interacts with the surgical field by means of a mechanical arm or arms. This article discusses the components of the system and the appropriate instrumentation for robotic surgery. Because of a unique feature of the robot arm drapes, they are considered part of the instrumentation, with economic implications. The proper use and care of robotic instruments is also discussed.




“Does robotic assistance improve efficiency in performing complex minimally invasive surgical procedures?”

Jayaraman, S., D. Quan, et al. (2010).

Surg Endosc 24(3): 584-588.


OBJECTIVE: We used a model of biliary-enteric anastomosis to test whether da Vinci robotics improves performance on a complex minimally invasive surgical (MIS) procedure. METHODS: An ex vivo model for choledochojejunostomy was created using porcine livers with extrahepatic bile ducts and contiguous intestines. MIS choledochojejunostomies were performed in two arms: group 1 (laparoscopic, n = 30) and group 2 (da Vinci assisted, n = 30). Procedures were performed by three surgeons with graduated MIS expertise: surgeon A (MIS + robotics), surgeon B (experienced MIS), and surgeon C (basic MIS). Each surgeon performed ten procedures per group. The primary objective was time to complete anastomoses using each method. Secondary objectives included anastomosis quality, impact of experience on performance, and learning curve. RESULTS: da Vinci led to faster anastomoses than laparoscopy (28.0 vs. 35.9 min, p = 0.002). Surgeon A’s mean operative times were equivalent with both techniques (24.5 vs. 22.3 min). Surgeons B and C experienced faster operative times with robotics over laparoscopy alone (39.4 vs. 28.6 min, p = 0.01; and 43.8 vs. 33.0 min, p = 0.008, respectively). Surgeon A did not demonstrate a learning curve with either laparoscopy (22.4 vs. 22.4 min, p = not significant, NS) or robotics (24.7 vs. 19.8 min, p = NS). Surgeon B demonstrated nonsignificant improvement with laparoscopy (46.6 vs. 39.5 min, p = NS). With robotic assistance, a learning curve was demonstrated (36.8 vs. 24.7 min, p = 0.02). Surgeon C demonstrated a learning curve with laparoscopy (58.3 vs. 33.2 min, p = 0.004), but no improvement was noted with robot assistance (32.2 vs. 34.7 min, p = NS). CONCLUSIONS: da Vinci improves time to completion and quality of choledochojejunostomy over laparoscopy in an ex vivo bench model. This advantage is more pronounced in the hands of surgeons with less MIS experience. Conversely, robotics may allow less experienced surgeons to perform more complex operations without first developing advanced laparoscopic skills; however, there may be benefit to first obtaining fundamental skills.




“Endosurgery of the future, today: lessons on how to bean innovator.”

Lobe, T. E. (2010).

Journal of Pediatric Surgery 45(2): 295-299.


This lecture summarizes the elements of innovation and demonstrates how one can apply the principles every day to be an effective surgical innovator. © 2010.




“Robotic assistance improves intracorporeal suturing performance and safety in the operating room while decreasing operator workload.”

Stefanidis, D., F. Wang, et al. (2010).

Surg Endosc 24(2): 377-382.


BACKGROUND: Intracorporeal suturing is one of the most difficult laparoscopic tasks. The purpose of this study was to assess the impact of robotic assistance on novice suturing performance, safety, and workload in the operating room. METHODS: Medical students (n = 34), without prior laparoscopic suturing experience, were enrolled in an Institutional Review Board-approved, randomized protocol. After viewing an instructional video, subjects were tested in intracorporeal suturing on two identical, live, porcine Nissen fundoplication models; they placed three gastro-gastric sutures using conventional laparoscopic instruments in one model and using robotic assistance (da Vinci) in the other, in random order. Each knot was objectively scored based on time, accuracy, and security. Injuries to surrounding structures were recorded. Workload was assessed using the validated National Aeronautics and Space Administration (NASA) task load index (TLX) questionnaire, which measures the subjects’ self-reported performance, effort, frustration, and mental, physical, and temporal demands of the task. Analysis was by paired t-test; p < 0.05 was considered significant. RESULTS: Compared with laparoscopy, robotic assistance enabled subjects to suture faster (595 +/- 22 s versus 459 +/- 137 s, respectively; p < 0.001), achieve higher overall scores (0 +/- 1 versus 95 +/- 128, respectively; p < 0.001), and commit fewer errors per knot (1.15 +/- 1.35 versus 0.05 +/- 0.26, respectively; p < 0.001). Subjects’ overall score did not improve between the first and third attempt for laparoscopic suturing (0 +/- 0 versus 0 +/- 0; p = NS) but improved significantly for robotic suturing (49 +/- 100 versus 141 +/- 152; p < 0.001). Moreover, subjects indicated on the NASA-TLX scale that the task was more difficult to perform with laparoscopic instruments compared with robotic assistance (99 +/- 15 versus 57 +/- 23; p < 0.001). CONCLUSIONS: Compared with standard laparoscopy, robotic assistance significantly improved intracorporeal suturing performance and safety of novices in the operating room while decreasing their workload. Moreover, the robot significantly shortened the learning curve of this difficult task. Further study is needed to assess the value of robotic assistance for experienced surgeons, and validated robotic training curricula need to be developed.




“Robotic technology in ophthalmic surgery.”

Swetha, V., E. Jeganathan, et al. (2010).

Current Opinion in Ophthalmology 21(1): 75-80.


Purpose of review To provide an overview of the history, development, and potential applications of robotic technology, with a focus on ophthalmic surgery. An extensive literature review and authors’ own perspectives were taken into account in selecting the most relevant articles from MEDLINE and Google scholar. Recent findings Most surgical specialties have introduced robots in current use. Although the application of robots in ophthalmic surgery is in its infancy today, its advantages and great potential is quite apparent. As robotics transcends utility and attain wider consensus among the surgical profession, ophthalmologists must acquaint themselves with this novel interdisciplinary field and its relevance to their specialty. Summary Future possibilities, including the prospects for nanotechnology in ophthalmology, are awaited. © 2010 Wolters Kluwer Health.




“A novel simulation model for minimally invasive spine surgery.”

Walker, J. B., E. Perkins, et al. (2009).

Neurosurgery 65(6 SUPPL. 1).


OBJECTIVE: Minimally invasive spine surgery (MISS) is among the fastest growing technologies in general neurosurgical practice. In addition, great demand exists to teach these skills to neurosurgery residents. With newly enforced work hour restrictions, opportunities to acquire these skills are limited, necessitating development of alternative strategies of education. We describe a novel simulation model for MISS supplemented by resident self-assessment analysis and evaluation. METHODS: The simulator was constructed using a nontransparent Plexiglas frame supplemented with a modified halo frame on which to affix spine specimens. Interchangeable copper tubing was affixed to a 360-degree pivot system to replicate a working portal. Deer skulls and spines were then collected and prepared accordingly. Laboratory exercises were based on the resident’s level of training with emphasis on proper drilling techniques. Eight neurosurgery residents were asked to complete the exercises and complete a self-assessment survey regarding their competence level on a scale of 0 to 5, both before and after completing the skill sets. Additionally, they were asked to complete an exit survey that was used to assess the simulation exercises. RESULTS: All exercises were completed successfully with the exception of placing 2 separate pedicle screws through the same portal, which posed difficulty on some specimens because of the of lack of lordosis of the specimens, leading to unfavorable trajectories using a free-hand technique. With regard to the resident self-assessment analysis, the mean confidence rating for performing an MISS laminectomy improved by a difference of 1.25 points (n = 8; 95% confidence interval, 0.66-1.84; P = 0.0015), from 2.50 to 3.75 before and after simulation exercises, respectively, and reached statistical significance. For the senior-level residents, the mean confidence rating for performing MISS placement of pedicle screws using a free-hand technique improved by a difference of 1.00 (n = 3; 95% confidence interval, -1.48-3.48; P = 0.225), from 3.33 to 4.33 before and after simulation exercises, respectively. Results of the exit survey were encouraging. CONCLUSION: The MISS simulator is a feasible, inexpensive, and reproducible adjunct to neurosurgery resident training and provides a new teaching method for spine surgery. Further investigation of this technology is warranted, although multicenter, randomized, controlled trials assessing its validity may not be practical because of ethical constraints with regard to patient safety. © 2009 by the Congress of Neurological Surgeons.