Toward effective pediatric minimally invasive surgical simulation

Background/Purpose

Simulation is increasingly being recognized as an important tool in the training and evaluation of surgeons. Currently, there is no simulator that is specific to pediatric minimally invasive surgery (MIS). A fundamental technical difference between adult and pediatric MIS is the degree of motion scaling. Smaller instruments and areas of dissection under greater optical magnification require finer, more precise hand movements. We hypothesized that this can be used to detect differences in skills proficiency between pediatric and general surgeons.

Methods

We programmed a virtual reality simulation of intracorporeal suturing with modes that used motion scaling to mimic conditions of either adult or pediatric MIS. The participants consisted of pediatric and general surgeons who wore motion-sensing gloves. Metrics included time elapsed, penetration errors, tool movement smoothness, hand movement smoothness, and gesture level proficiency.

Results

For all measures, pediatric surgeons demonstrated superior proficiency on exercises conducted in pediatric conditions (P < .05). Performance in adult conditions was similar between the 2 groups.

Conclusion

Pediatric surgeons possess unique skills compared with general surgeons that relate to the technical challenges they routinely face, reinforcing the need for a surgical simulator specific to pediatric MIS. This validates our simulator and the manipulation of motion scaling as a useful training tool.     

Validation of a six-task simulation model in minimally invasive surgery

Background The content validity of currently available inanimate simulation models is questionable, because some tasks seem too far from clinical reality. The aim of this study was to validate a simulation model with six tasks commonly used in clinical practice (6-TSM) for the acquisition of psychomotor skills in minimally invasive surgery (MIS).Methods This was a prospective randomized trial comparing the 6-TSM to a previously described three-task training method (3-TTM). All first, second, and third postgraduate year surgical residents were eligible. The 6-TSM included clipping and dividing of a vessel, excision of lesion, appendectomy, mesh repair, suturing perforation, and hand-sewn anastomosis. The outcome measures of 6-TSM included accuracy error, tissue damage, sliding knot, leak, operating time, and dangerous movements. After completion of training, 6-TSM and 3-TTN residents were tested by the Minimally Invasive Surgical Trainer—Virtual Reality (MIST-VR). Criterion-related and construct validity, responsiveness, test–retest, and interrater reliability were assessed.Results During six months, 17 residents underwent training with the 6-TSM or the 3-TTM as allocated. The mean duration of training with 6-TSM and 3-TTM was similar (7.8 vs 8.1 h). The criterion-related validity of the 6-TSM was shown by significantly increased skill improvement in the 6-TSM residents, as compared with the 3-TTM residents at MIST-VR. Construct validity the of 6-TSM was shown by the finding that the experts baseline was superior to the residents baseline. The responsiveness of the 6-TSM was shown by the significantly increased skill improvement of the 6-TSM residents in sliding knot, leak, and operating time. The test–retest reliability of the 6-TSM was good (> 0.80), except for accuracy error and dangerous movements (Cronbachs intraclass correlation coefficient : 0.57, p < 0.0001; 0.62, p < 0.0001, respectively). The interrater reliability of the 6-TSM was good (>0.80) except for leak (Kendalls concordance coefficient tau_b:0.76, p = 0.06 for hand-sewn anastomosis) and dangerous movements (tau_b:0.72, p = 0.08 for suturing perforation and tau_b:0.68, p = 0.10 for hand-sewn anastomosis). The perresident cost for 6-TSM was $769.Conclusions The 6-TSM is a valid and reliable learning tool for surgical residents acquisition of laparoscopic motor skills.     

Procedural virtual reality simulation in minimally invasive surgery

Background

Simulation of procedural tasks has the potential to bridge the gap between basic skills training outside the operating room (OR) and performance of complex surgical tasks in the OR. This paper provides an overview of procedural virtual reality (VR) simulation currently available on the market and presented in scientific literature for laparoscopy (LS), flexible gastrointestinal endoscopy (FGE), and endovascular surgery (EVS).

Methods

An online survey was sent to companies and research groups selling or developing procedural VR simulators, and a systematic search was done for scientific publications presenting or applying VR simulators to train or assess procedural skills in the PUBMED and SCOPUS databases.

Results

The results of five simulator companies were included in the survey. In the literature review, 116 articles were analyzed (45 on LS, 43 on FGE, 28 on EVS), presenting a total of 23 simulator systems. The companies stated to altogether offer 78 procedural tasks (33 for LS, 12 for FGE, 33 for EVS), of which 17 also were found in the literature review. Although study type and used outcomes vary between the three different fields, approximately 90 % of the studies presented in the retrieved publications for LS found convincing evidence to confirm the validity or added value of procedural VR simulation. This was the case in approximately 75 % for FGE and EVS.

Conclusions

Procedural training using VR simulators has been found to improve clinical performance. There is nevertheless a large amount of simulated procedural tasks that have not been validated. Future research should focus on the optimal use of procedural simulators in the most effective training setups and further investigate the benefits of procedural VR simulation to improve clinical outcome.     

Utility of a voice-activated system in minimally invasive surgery

BACKGROUND: Advances in computer enhancements for surgery, including a voice-activated control system for minimally invasive surgery, are being introduced into clinical practice. Few reports have objectively evaluated the utility of the voice-activated control system. The aim of this study was to evaluate the utility of a voice-activated control system for delivery of commands to specific operating room (OR) equipment. MATERIALS AND METHODS: We evaluated a total of 30 laparoscopic procedures: 15 laparoscopic hernia repairs, 10 laparoscopic cholecystectomies, and 5 laparoscopic fundoplications performed with the HERMEStrade mark Operating Room Control Center (Computer Motion, Santa Barbara, California) voice-activated control system. When the voice command (VC) to the HERMES system was given, the circulating nurse was observed and her location was recorded. The 3 locations were A, the nurse was immediately available in the OR, not engaged in any other tasks; B, the nurse was in the OR but engaged in other tasks; or C, the nurse was outside the OR. RESULTS: The 30 cases were performed by the same surgeon and completed laparoscopically. For 170 VCs for gas insufflation, the location of the circulating nurse was: A=50, B=98, and C=22. For 135 light source adjustments, the locations were A=34, B=82, and C=19. In 76 white balance VCs: A=16, B=51, and C=9. In 128 VCs for camera adjustment: A=27, B=77, and C=24. Eight video capture VCs: A=1, B=3, and C=4. For 69 image capture VCs: A=5, B=41, and C=23. The total number of VCs was 586: A=133 (22.7%), B=352 (60%), and C=101(17.3%). All VCs were accurately interpreted by the HERMES system. CONCLUSION: Voice-activated control systems improve communication with and efficiency of OR staff. The surgeon is afforded the most timely equipment adjustment possible. Circulating nurses are allowed to concentrate on patient care instead of equipment adjustment during the course of the surgery.     

Anesthesia for minimally invasive surgery

Canadian Journal of Anesthesia/Journal canadien d'anesthésie -     

Training for minimally invasive surgery

Summary Controversy exists regarding the training of surgeons for the performance of minimally invasive surgical procedures. The use of live animals is essential, especially in teaching dissection techniques. Seventeen percent of animals experienced excessive operative hemorrhage, which contributed to premature mortality during training exercises, demonstrating the need for live animals in this component of the training. A number of abdominal procedures can be performed with minimally invasive techniques without suturing by utilizing a rapidly expanding array of devices. However, other procedures cannot be successfully accomplished without suturing skills. Laparoscopic suturing skills are particularly demanding; thus specific training and practice prior to hands-on exercises in animal models is recommended. Emphasis on acquisition of advanced laparoscopic surgical skills is a necessity.Presented at the Third World Congress of Endoscopic Surgery, June 20, 1992, Bordeaux, France     

Instruments for minimally invasive surgery

Although the advantages of minimally invasive surgery (MIS) have been clearly established for the patient, the surgeon must cope with disadvantages caused by unergonomic instrument handles. Pressure areas and persisting nerve lesions have been described in the literature. The shape of the instrument handles has been identified as the reason for these disorders. To prevent these, it is necessary to use ergonomically designed handles for MIS instruments. Anatomic, physiologic, and ergonomic facts as well as the results of the authors' own experiences and tests are presented. On this basis, an ideal ergonomic working posture for the laparoscopic surgeon and an optimal grasp for manipulating the instruments' functional elements are recommended. To enable the surgeon to evaluate ergonomic handles for MIS instruments according to his own needs, 14 criteria for genuine ``ergonomic handles' are established. On the basis of these criteria, deficiencies of handles currently available (ring and shank handles at an angle or with axial extension to the instrument shaft, and pistol handles) are discussed. Furthermore, new handles, developed by the authors according to the criteria for genuine ergonomic handles, are presented. Received: 12 September 1997/Accepted: 28 May 1998     

Anaesthesia for minimally invasive cardiac surgery

Minimally invasive cardiac surgery is used for both extracardiac and intracardiac procedures. Extracardiac procedures, such as coronary artery bypass grafting, are often performed on a beating heart. Intracardiac procedures are done with the aid of cardiopulmonary bypass. The surgery is performed via a minithoracotomy or a ministernotomy. Thoracoscopic video-assisted surgery, often with robotic assistance, necessitates prolonged one-lung ventilation to optimize exposure. Port-access surgery will require appropriate positioning of various catheters to establish cardiopulmonary bypass. Adequate flow during cardiopulmonary bypass may require suction augmentation of venous return and may increase the risk of air emboli. Limited exposure of the heart during surgery poses challenges with management of arrhythmia, haemostasis, myocardial protection and de-airing at the end of surgery. Patient selection is important to avoid intra-operative and post-operative complications. Prolonged single-lung ventilation, incomplete revascularization in hybrid procedures, and limited access for rapid intervention pose challenges with patient management. Conversion to sternotomy that may be required occasionally and extension of portals over several dermatomal segments mandate a versatile analgesic technique.     

Mirror glasses for minimally invasive surgery

Introduction The operator performing minimally invasive surgery is prevented from seeing the whole field with both eyes by the restricted small thoracotomy incision. To overcome this problem, we developed mirror glasses. Methods Use of these glasses was evaluated in terms of the time required for threading of sutures with endoscopic forceps. Three surgeon ligated thread a suture five times with and without use of the glasses in the box, and the mean time was calculated for each surgeon. Results The time required for ligation (mean ± SD) was 24.2 ± 2.9 s with mirror glasses and 27.0 ± 2.5 s without the glasses (p = 0.01). Conclusion The mirror glasses may be found useful for fine manipulation for minimally invasive surgery.     

Automation of a suturing device for minimally invasive surgery

Background  

In minimally invasive surgery, hand suturing is categorized as a challenge in technique as well as in its duration. This calls for an easily manageable tool, permitting an all-purpose, cost-efficient, and secure viscerosynthesis. Such a tool for this field already exists: the Autosuture EndoStitch^?. In a series of studies the potential for the EndoStitch to accelerate suturing has been proven. However, its ergonomics still limits its applicability. The goal of this study was twofold: propose an optimized and partially automated EndoStitch and compare the conventional EndoStitch to the optimized and partially automated EndoStitch with respect to the speed and precision of suturing.