[Validity studies in laparoscopic simulation. Methodology and design considerations.] / Validación en simulación laparoscópica. Consideraciones metodológicas y de diseño.

OBJECTIVES: To describe a roadmap of the most representative milestones and considerations in the validation of surgical simulators, especially those of laparoscopic surgery. And additionally, help determine when in this process a simulator can be considered as validated. METHODS: A non-systematic review was carried out searching terms like simulation, validation, training, assessment, skills and learning curve, as well as providing the experience accumulated by our center. RESULTS: An ideal classical validation process should consist of the following steps: fidelity, verification/calibration/ reliability, subjective and objective strategies. Baseline tests of fidelity and verification/calibration/ technological reliability are not always detailed in the simulation literature. A simulator can be considered validated if, at least, satisfactorily completed any of the two main objective strategies, that is, constructive and/or criterion validity. CONCLUSIONS: The methodologies to validate simulators as useful and reliable for the improvement of psychomotor/ technical skills are widely analyzed, although there is a variety of approaches depending on the scientific reference consulted, not being implemented equally in all works. This apparent arbitrariness should be considered in advance because it can lead the researcher to misunderstandings, especially when the simulator will be regarded as valid.

OBJETIVOS: Describir una hoja de ruta de los hitos y consideraciones más representativos en la validación de simuladores quirúrgicos, especialmente los de cirugía laparoscópica. Y adicionalmente contribuir a determinar en qué momento de este proceso puede considerarse un simulador como validado.MÉTODOS: Se realizó una revisión no sistemática con los términos simulación, validación, formación, entrenamiento, evaluación, habilidades y curva de aprendizaje, además de aportar la experiencia acumulada por nuestro centro. RESULTADOS: Un proceso ideal clásico de validación debería constar de los siguientes pasos: Fidelidad, Verificación/ Calibración/Fiabilidad, estrategias subjetivas y objetivas. Las pruebas de inicio tanto de Fidelidad como de Verificación/Calibración/Fiabilidad tecnológica no siempre están descritas de manera explícita en los trabajos de validación de simuladores. Un simulador puede considerarse validado si al menos ha completado satisfactoriamente una validación de cualquiera de los dos grandes bloques de tipo objetivo, es decir, constructiva y/o de criterio. CONCLUSIONES: Los métodos que permiten validar simuladores como útiles y fiables para la mejora de habilidades de tipo psicomotor/técnico están ampliamente documentados aunque existe cierta variedad de enfoques en función de la referencia científica que se consulte, no aplicándose por igual en todos los trabajos. Esta aparente arbitrariedad debería ser conocida de antemano porque puede llevar al investigador a ciertos equívocos, especialmente a la hora de afirmar cuándo el simulador se considera plenamente validado.

Laparoscopic Partial Nephrectomy With Potassium-titanyl-phosphate Laser Versus Conventional Laparoscopic Partial Nephrectomy: An Animal Randomized Controlled Trial.

OBJECTIVE: To explore the feasibility, safety, and short-term results of potassium-titanyl-phosphate (KTP) laser laparoscopic partial nephrectomy (KTP-LPN) vs conventional laparoscopic partial nephrectomy (C-LPN). MATERIALS AND METHODS: Thirty large white female pigs were randomized to KTP-LPN or C-LPN. Laparoscopic radical right nephrectomy was performed, and an artificial renal tumor was placed in the left kidney in 3 locations. A week later, 15 pigs underwent C-LPN and 15 underwent KTP-LPN. All C-LPNs were performed with renal ischemia. A 120-W setting was used, without arterial clamping in the KTP-LPN group. Follow-up was done at day 1, week 3, and week 6. Retrograde pyelography was performed at 6 weeks, followed by animal sacrifice and necropsy. RESULTS: All KTP-LPNs were performed without hilar clamping. C-LPNs were performed with hilar clamping, closing of the collecting system, and renorraphy. In the KTP laser group, 2 pigs died due to urinary fistula in the first week after surgery. In the C-LPN group, 1 pig died due to myocardial infarction and another due to malignant hyperthermia. Hemoglobin and hematocrit recovery were lower at 6 weeks in the KTP-LPN group. Renal function 24 hours after surgery was worse in the KTP-LPN group but recovered at 3 weeks and 6 weeks. No differences were observed in surgical margins. The necropsy showed no differences. Limitations of the study are the impossibility to analyze the collecting tissue sealing by the KTP, and the potential renal toxicity of the KTP laser. CONCLUSION: Although KTP-LPN is feasible and safe in the animal model, further studies are needed.

Laparoscopic Cholecystoduodenostomy in Dogs: Canine Cadaver Feasibility Study.

OBJECTIVE: To evaluate the feasibility of laparoscopic cholecystoduodenostomy in canine cadavers using barbed self-locking sutures. STUDY DESIGN: In vivo experimental study. ANIMALS: Fresh male Beagle cadavers (n=5). METHODS: Surgery was performed by a single veterinary surgeon. Dogs were placed in dorsal recumbency and 15° reverse Trendelenburg position. The surgical procedure was performed with four 5 mm entry ports and a 5 mm 30° telescope. The cholecystoduodenostomy technique included dissection, incision of the gallbladder, and lavage, followed by gallbladder transposition over the duodenum, incision of the duodenum, and anastomosis. The latter was performed with a 4-0 barbed self-locking suture (V-Loc® 180). Subsequently, a leak test was performed by submerging the anastomosis in saline and insufflating air into the duodenum through a catheter. Total operative time and completion times for each procedural step were recorded. RESULTS: The median total operative time was 151 minutes (range, 129-159). One conversion to open surgery occurred because of vascular hemorrhage. The 3 longest intraoperative steps were posterior wall anastomosis, gallbladder dissection, and anterior wall anastomosis. Intraoperative anastomotic leakage sites were identified in 3 of 5 dogs. Leaks were managed by placement of a single reinforcing conventional intracorporeal suture, which was adequate to obtain a watertight anastomosis. CONCLUSION: This technique cannot be recommended in clinical practice until further studies are performed and the technique is further refined.

Changes on Adipose Tissue Distribution After Laparoscopic Roux-en-Y Gastric Bypass in Obese Göttingen Minipig. Effects on Glucose Metabolism.

BACKGROUND: The objective of the study was to assess Roux-en-Y independent-to-weight metabolic effects on an obese Gottingen minipig. METHODS: Eleven castrated Göttingen minipigs were enrolled. Minipigs became obese after a 9-month period of experimental diet. The animals were then subjected to a laparoscopic Roux-en-Y gastric bypass (period P1) followed by 4 months of follow-up (period P2). During this last period, they were fed to maintain similar body weight to that observed at the day of surgery. Registered parameters during each period included biometric variables; abdominal adipose tissue (AT) distribution; lipid profile; HOMA-IR; and fasting plasma leptin, adiponectin, glucose, insulin and fructosamine. RESULTS: Two pigs were unable to complete the study due to postoperative complications. Four months after surgery, the body weight (kg) was maintained (P1 51.90 ± 5.78 vs P2 51.47 ± 5.68). On the contrary, intraperitoneal AT (p < 0.0001), glucose (mmol/L) (P1: 5.53 ± 0.37 vs 4.66 ± 0.72, p = 0.019), fructosamine (µmol/L) (p = 0.0001) and insulin (pmol/L) (P1: 36.66 ± 13.94 vs P2: 21.42 ± 12.62, p = 0.001) significantly decreased after surgery. Lipid profile showed a significant increase after high-fat feeding period and a slight reduction at P2, which continued increasing. At the end of the study, leptin plasma levels (ng/mL) showed a significant reduction compared to basal value (p = 0.001). CONCLUSIONS: The improvement in glucose metabolism seems to occur by means of the redistribution of body fat. In order to fully confirm this hypothesis, more studies including the evaluation of incretins and inflammatory molecules, as well as a glycaemia control study against glucose load, are needed.

Assessment of Laparoscopic Skills in Veterinarians Using a Canine Laparoscopic Simulator.

The aim of the present study was to assess the content and construct validity of the Canine Laparoscopic Simulator (CLS). Forty-two veterinarians were assigned to experienced (n=12), control (n=15), and training (n=15) groups, which were assessed while performing four laparoscopic tasks on the CLS. The initial and final assessments of all tasks were performed blindly by two experienced surgeons using the Global Operative Assessment of Laparoscopic Skills (GOALS) and a task-specific checklist. At the end of the study, the subjects completed an anonymous survey. The experienced group performed all of the tasks faster, with higher GOALS and checklist scores than the training and control groups (p≤.001). In the second assessment, the training group reduced the time needed to complete all of the tasks and obtained significantly higher GOALS and checklist scores than the control group. The participants perceived the CLS and its training program to be positive or very positive. The CLS and its training program demonstrated content and construct validity, supporting the suitability of the simulator for training and teaching and its ability to distinguish the degree of experience in laparoscopic surgery among veterinarians. In addition, face validity showed that the veterinarians fully accepted the CLS's usefulness for learning basic laparoscopic skills.

Laparoscopic ovariectomy in dogs: comparison between laparoendoscopic single-site and three-portal access.

This study was conducted to evaluate the feasibility and therapeutic safety of laparoendoscopic single-site ovariectomy (LESS-OVE) and 3-portal laparoscopic ovariectomy (Lap-OVE) in dogs. Ten female mixed breed dogs were included in the study. Dogs were divided into group 1 (LESS-OVE; n = 5) and group 2 (Lap-OVE; n = 5). All procedures were performed by laparoscopic-skilled surgeons, and the anesthetic protocol was the same for all patients. In both groups, the ovarian vascular pedicle and ligaments were transected using a bipolar vessel sealer/divider device. The mean total surgical time was slightly longer in LESS-OVE (36.6 ± 3.5 min) than Lap-OVE (32.0 ± 3.0 min); however, the differences were not significant. Perioperative complications were not reported in any group. Both laparoscopic techniques were shown to be equally feasible and safe for patients. However, surgeons found LESS-OVE to require more skill than Lap-OVE. Therefore, additional studies should be conducted to evaluate this novel approach in clinical veterinary practice, and a proper laparoscopic training program for veterinary surgeons should be developed.

Development and evaluation of a canine laparoscopic simulator for veterinary clinical training.

Human laparoscopic simulators have been used in medical education for minimally invasive surgery (MIS) in the past years. Simulator-based laparoscopic training has attracted much interest because unique skills have to be learned not only by surgeons in training but also by surgeons in practice. MIS forces the surgeon to adapt to monocular vision and decreased tactile sensation and entails training and improving hand-eye and hand-hand coordination. Those skills require a learning curve that could be overcome gradually with use of simulators. The Canine Laparoscopic Simulator (CLS) for laparoscopic training was developed based on the working and optical space obtained from computed tomography (CT) scan images of three Beagle dogs. Thirty veterinarians (expert group, n=7; novice group, n=23) performed basic laparoscopic exercises in one training session on the CLS. During the performance of the exercises, an experienced laparoscopic veterinarian assessed all the tasks. Afterwards, participants were asked to complete an anonymous survey describing their experience. Most participants expressed positive opinions about the design and usability of the CLS. There were no significant differences between the two groups' opinions. The CLS showed good preliminary acceptance in the basic laparoscopy tasks by veterinarians. They perceived it to be a good training tool, and these results suggest that CLS is an engaging tool for education but still has some limitations inherent in training boxes. Further studies would be needed to establish the validity of training programs performed in the CLS.

Comparison of single access devices during cut and suturing tasks on simulator.

BACKGROUND: Published comparisons of the different available laparoendoscopic single-site surgery (LESS) devices focused on its economic cost and technical aspects. With this study, we aimed to objectively compare the use of three different LESS access devices in controlled experimental tasks. MATERIALS AND METHODS: Twenty subjects participated in simulator trials. A cut and an intracorporeal suturing task were carried out. Three single access devices (SILS: SILS(TM) Port, GPN. GelPOINT Advanced Access Platform, and XCN: XCONE) were used according to a randomized nine-session schedule. Completion time was registered and performance objectively assessed with task-specific rating scales. Two blinded expert raters worked over video recordings of the hands-on sessions. RESULTS: Participants showed improvement with all devices on total cut completion times and significantly for SILS (P = 0.017). The GPN decreased its adapted Global Rating Scale score (P = 0.002) from the first (W1) to the last week (W9). On the suture task, XCN constituted the device with longer completion times compared with SILS (P < 0.001) and to GPN (P < 0.001). There was significant improvement in times from W1 to W9 with XCN (P < 0.001), SILS (P = 0.003), and GPN (P < 0.001). On average summative score, we observed significant improvement in performance with all devices from W1 to W9 (SILS: P = 0.003; GPN: P = 0.001; and XCN: P < 0.001). CONCLUSIONS: Although we advise surgeons to focus on the specific procedures and patient characteristics to select the most adequate access device to maintain procedural safety standards, single-use devices appear to confer an easier adaptation to LESS surgery.

Ureteral obstruction swine model through laparoscopy and single port for training on laparoscopic pyeloplasty.

This study aims firstly to assess the most adequate surgical approach for the creation of an ureteropelvic juntion obstruction (UPJO) animal model, and secondly to validate this model for laparoscopic pyeloplasty training among urologists. Thirty six Large White pigs (28.29±5.48 Kg) were used. The left ureteropelvic junction was occluded by means of an endoclip. According to the surgical approach for model creation, pigs were randomized into: laparoscopic conventional surgery (LAP) or single port surgery (LSP). Each group was further divided into transperitoneal (+T) or retroperitoneal (+R) approach. Time needed for access, surgical field preparation, wound closure, and total surgical times were registered. Social behavior, tenderness to the touch and wound inflammation were evaluated in the early postoperative period. After ten days, all animals underwent an Anderson-Hynes pyeloplasty carried out by 9 urologists, who subsequently assessed the model by means of a subjective validation questionnaire. Total operative time was significantly greater in LSP+R (p=0.001). Tenderness to the touch was significantly increased in both retroperitoneal approaches, (p=0.0001). Surgeons rated the UPJO porcine model for training on laparoscopic pyeloplasty with high or very high scores, all above 4 on a 1-5 point Likert scale. Our UPJO animal model is useful for laparoscopic pyeloplasty training. The model created by retroperitoneal single port approach presented the best score in the subjective evaluation, whereas, as a whole, transabdominal laparoscopic approach was preferred.

[Training and research in urologic laparoscopic surgery. Design of training programs and experimental models of renal tumor]. / Formación e investigación en cirugía laparoscópica urológica. Diseño de programas formativos y modelos experimentales de tumor renal.

We present our experience with surgical training programs development for basic and advanced laparoscopic urological surgery. Both training programs consist of 21 and 28 hours respectively. Basic surgical programs start with general knowledge of ergonomics and instrumentation, there after, attendants acquire basic skills on physical simulator. Posteriorly, techniques on animal model are undertaken, always assisted by an expert. Advanced activities start with surgical tasks on physical simulator. Posteriorly, reconstructive urological surgical techniques are undertaken on animal model, focused on partial nephrectomy, and always assisted by an expert tutor. We present our results on exophytic renal tumour model creation based chromatic Alginate.