Laparoscopic Urethrovesical Anastomosis: A Model to Assess Surgical Competency

Videolaparoscopic prostatectomy in porcine model for training residents

Introduction:

Surgical training models prepare the resident for a more ethical surgical practice as well as providing a less steep learning curve. In urology, there are well-known models of pyeloplasty simulation, urethro-vesical anastomosis and nephrectomy, which have helped in the training of urology residents (1–3). Learning laparoscopic prostatectomy is a difficult surgery and requires advanced surgical skill from the surgeon (4), requires operate without a direct view of the surgical field in a two-dimensional space and with longer instruments (5).

Laparoscopic prostatectomy step by step makes the surgeon's learning curve less difficult, lead to less intraoperative complications, such as blood loss, while also enabling shorter operative time and less positive surgical margins (6).

The objective of surgical models is to simulate surgical procedures in a reliable way thus preparing the surgeon for his daily practice, surgical simulations in animal models have been described to compensate for inadequate clinical exposure (7).

The canine model of prostate cancer has many similarities with humans. Despite trying to develop a model that is as credible as possible, there are ethical issues in several countries, such as Brazil, that do not allow the use of live dogs for scientific experimentation and there is a difficulty in not standardizing the animals used (8, 9).

The swine surgical training model is widely known, accepted and used as a valuable tool in the teaching of new surgeons (10).

The porcine video laparoscopic prostatectomy model allows the urologist in training to exercise the skills required in a real surgical situation, practicing them in a single session (10). We will present an experimental model in pigs for training urology residents in laparoscopic radical prostatectomy with current techniques (11–13).

The limitations found are that the prostate has no limits as well defined as in humans, the urethra is long and coiled, the fat surrounding the pelvic organs is scarce and there is no postoperative follow-up for evaluating functionality after the procedure, as well as the effectiveness of the surgery with surgical margins. However, it is similar in surgical model presented, it is reproducible and can provide a realistic simulation environment to the beginner surgeon.

Material and Methods:

In this paper, according to the institutional protocol approved by the institutional ethics and research committee FMUSP n° 964/2017 and protocol was in accordance with current international regulations for the use of animals in Research: Reporting In Vivo Experiments (ARRIVE) guide. Ten male pigs weighing 20 to 22kg were used. The animals were anesthetized with a combination of Telazol (5mg/kg), Xylazine (1.5mg/kg), Cetamine (22mg/kg) and Atropine (0.04mg/kg) for orotracheal intubation followed by Isoflurane (2%). Animals were euthanized at the end of the procedure with a lethal dose of KCl (2mEq/kg). The trocar insertion points were marked using the epigastric vessels and umbilical region as reference points. Initially, urethral catheterization was performed using a hydrophilic Nitinol guidewire, followed by a perineal incision to dissect the tortuous urethra of the porcine model. A malleable urethral catheter 8Fr was inserted into their bladder. The animal was placed in the Trendelenburg position inserted and 12mm trocars were inserted in its umbilical region, utilizing 10mm in the surgeon's dominant hand, 5mm in his non-dominant hand of the surgeon, and 5mm in the first assistant's trocar.

The surgeon replicates the steps performed in a laparoscopic radical prostatectomy in humans, including the bladder catheterization, dissection of the anterior bladder plane, the vesicular and prostatic dissection, the suture of the dorsal venous plexus, a prostatectomy, an urethral vesical anast omosis, as well as the waterproof test, even including the performing of surgical steps using current concepts of anterior urethral suspension as the reconstruction of the posterior plane of the rhabdosphincter.

Results:

All steps of surgery could be reproduced in all ten porcine cases. No significant bleeding was observed and the surgical time was gradually reduced fifty percent from case one to last cases.

Conclusions:

The porcine model allowed the surgeon to replicate all the steps usually performed in a laparoscopic radical prostatectomy. The junior surgeons are better prepared to such difficult surgery. However, further studies will be necessary to prove the impact of the animal model presented in urological clinical practice.

Current status of wet lab and cadaveric simulation in urological training: A systematic review

INTRODUCTION

We undertook a systematic review of the use of wet lab (animal and cadaveric) simulation models in urological training, with an aim to establishing a level of evidence (LoE) for studies and level of recommendation (LoR) for models, as well as evaluating types of validation.

METHODS

Medline, EMBASE, and Cochrane databases were searched for English-language studies using search terms including a combination of "surgery," "surgical training," and "medical education." These results were combined with "wet lab," "animal model," "cadaveric," and "in-vivo." Studies were then assigned a LoE and LoR if appropriate as per the education-modified Oxford Centre for Evidence-Based Medicine classification.

RESULTS

A total of 43 articles met the inclusion criteria. There was a mean of 23.1 (±19.2) participants per study with a median of 20. Overall, the studies were largely of low quality, with 90.7% of studies being lower than LoE 2a (n=26 for LoE 2b and n=13 for LoE 3). The majority (72.1%, n=31) of studies were in animal models and 27.9% (n=12) were in cadaveric models.

CONCLUSIONS

Simulation in urological education is becoming more prevalent in the literature, however, there is a focus on animal rather than cadaveric simulation, possibly due to cost and ethical considerations. Studies are also predominately of a low LoE; higher LoEs, especially randomized controlled studies, are needed.

Current Status of Simulation Training in Urology: A Non-Systematic Review

Simulation has emerged as an effective solution to increasing modern constraints in surgical training. It is recognized that a larger proportion of surgical complications occur during the surgeon's initial learning curve. The simulation takes the learning curve out of the operating theatre and facilitates training in a safe and pressure-free environment whilst focusing on patient safety. The cost of simulation is not insignificant and requires commitment in funding, human resources and logistics. It is therefore important for trainers to have evidence when selecting various simulators or devices. Our non-systematic review aims to provide a comprehensive up-to-date picture on urology simulators and the evidence for their validity. It also discusses emerging technologies and future directions. Urologists should embed evidence-based simulation in training programs to shorten learning curves while maintaining patient safety and work should be directed toward a validated and agreed curriculum.

Validation of a new artificial model for simulated training of a laparoscopic vesicourethral anastomosis

OBJECTIVE

The aim of this study is to prove the effectiveness of a low cost, artificial model for training of a laparoscopic urethrovesical anastomosis.

MATERIALS AND METHODS

This study included urologists who attended specialised courses on laparoscopic radical prostatectomy (LRP) held during the period 2015 to 2017. They were divided into 2 groups according to their previous experience in laparoscopic surgery. The tasks performed on the artificial simulator were prostate resection, "task 1", and urethrovesical anastomosis, "task 2". Once these exercises were completed, the study participants filled in an anonymous questionnaire regarding their demographic data and experience level in laparoscopic surgery (LS). In addition, they gave their opinions about the didactic capacity of the artificial organ and evaluated its usefulness as a tool for LRP training. To demonstrate face and content validity, the participants judged the texture, consistency, morphology and evaluated its similarity to the real organ. The assessment was made with a five-point Likert scale.

RESULTS

The students were divided into 2groups: 10 experts (Group E) and 12 novices (Group N). The only significant difference between the scores of novices and experts was regarding the inclusion of this tool in the training programs (Group E=5 points versus group N=4.4±0.59, P=.024). The experts' group rated all the items with higher scores than the novices' one. Regarding the general assessment of the simulation model, the novice participants gave an average score of 8.00±0.91 points out of 10, while the experts' group granted higher scores of 9.4±0,51.

CONCLUSION

This artificial model has shown to have an elevated face, content and construct validity, as well being an optimal didactic tool for training in the techniques of prostate resection and laparoscopic urethrovesical anastomosis.

A new training model for robot-assisted urethrovesical anastomosis and posterior muscle-fascial reconstruction: the Verona training technique

A training model is usually needed to teach robotic surgical technique successfully. In this way, an ideal training model should mimic as much as possible the "in vivo" procedure and allow several consecutive surgical simulations. The goal of this study was to create a "wet lab" model suitable for RARP training programs, providing the simulation of the posterior fascial reconstruction. The second aim was to compare the original "Venezuelan" chicken model described by Sotelo to our training model. Our training model consists of performing an anastomosis, reproducing the surgical procedure in "vivo" as in RARP, between proventriculus and the proximal portion of the esophagus. A posterior fascial reconstruction simulating Rocco's stitch is performed between the tissues located under the posterior surface of the esophagus and the tissue represented by the serosa of the proventriculus. From 2014 to 2015, during 6 different full-immersion training courses, thirty-four surgeons performed the urethrovesical anastomosis using our model and the Sotelo's one. After the training period, each surgeon was asked to fill out a non-validated questionnaire to perform an evaluation of the differences between the two training models. Our model was judged the best model, in terms of similarity with urethral tissue and similarity with the anatomic unit urethra-pelvic wall. Our training model as reported by all trainees is easily reproducible and anatomically comparable with the urethrovesical anastomosis as performed during radical prostatectomy in humans. It is suitable for performing posterior fascial reconstruction reported by Rocco. In this context, our surgical training model could be routinely proposed in all robotic training courses to develop specific expertise in urethrovesical anastomosis with the reproducibility of the Rocco stitch.

[Animal model for training in laparoscopic pyeloplasty]

OBJECTIVE

With the coming of the laparoscopy, multiple surgical techniques have been developed that have revolutionized the urological practice. The laparoscopic pyeloplasty has been one of the techniques most developed. However, there are very few training models that permit the surgeon to decrease the learning curve. An animal model of training for the laparoscopic pyeloplasty technique is described.

METHODS

Eight procedures of laparoscopic pyeloplasty were performed using the animal model (Gallus gallus) in the laparoscopic practice laboratory of the Urology Service of the University Hospital of Caracas. The preparation times of the model and the operation times of each surgeon were compared. The statistical analysis was made calculating the mean operation time, standard deviation, frequencies and percentages. A significant value was considered as p < 0.05.

RESULTS

The laparoscopic pyeloplasty procedure was performed successfully in all of the cases by two surgeons. The preparation time ranged from a maximum of 14 minutes to a minimum of 6 minutes, this being the same for both surgeons in the fourth case. The operation time ranged from a maximum of 65 minutes to a minimum of 43 minutes, observing significant differences when comparing the times individually for each surgeon. Only one case had filtration when comparing the patency of the specimen.

CONCLUSIONS

The animal model of training of laparoscopic pyeloplasty that is described is economical, reproducible, of easy availability and it makes it possible to develop laparoscopic surgical skills and competency necessary for reconstructive surgery and techniques that warrant intracorporeal suture.