Robotic kidney autotransplantation in a porcine model: a procedure-specific training platform for the simulation of robotic intracorporeal vascular anastomosis

The First Entirely 3D-Printed Training Model for Robot-assisted Kidney Transplantation: The RAKT Box

Background

Robot-assisted kidney transplantation (RAKT) is increasingly performed at selected referral institutions worldwide. However, simulation and proficiency-based progression training frameworks for RAKT are still lacking, making acquisition of the RAKT-specific skill set a critical unmet need for future RAKT surgeons.

Objective

To develop and test the RAKT Box, the first entirely 3D-printed, perfused, hyperaccuracy simulator for vascular anastomoses during RAKT.

Design setting and participants

The project was developed in a stepwise fashion by a multidisciplinary team including urologists and bioengineers via an iterative process over a 3-yr period (November 2019-November 2022) using an established methodology. The essential and time-sensitive steps of RAKT were selected by a team of RAKT experts and simulated using the RAKT Box according to the principles of the Vattituki-Medanta technique. The RAKT Box was tested in the operating theatre by an expert RAKT surgeon and independently by four trainees with heterogeneous expertise in robotic surgery and kidney transplantation.

Surgical procedure

Simulation of RAKT.

Measurements

Video recordings of the trainees' performance of vascular anastomoses using the RAKT Box were evaluated blind by a senior surgeon according to the Global Evaluative Assessment of Robotic Skills (GEARS) and Assessment of Robotic Console Skills (ARCS) tools.

Results and limitations

All participants successfully completed the training session, confirming the technical reliability of the RAKT Box simulator. Tangible differences were observed among the trainees in both anastomosis time and performance metrics. Key limitations of the RAKT Box include lack of simulation of the ureterovesical anastomosis and the need for a robotic platform, specific training instruments, and disposable 3D-printed vessels.

Conclusions

The RAKT Box is a reliable educational tool to train novice surgeons in the key steps of RAKT and may represent the first step toward the definition of a structured surgical curriculum in RAKT.

Patient summary

We describe the first entirely 3D-printed simulator that allows surgeons to test the key steps of robot-assisted kidney transplantation (RAKT) in a training environment before performing the procedure in patients. The simulator, called the RAKT Box, has been successfully tested by an expert surgeon and four trainees. The results confirm its reliability and potential as an educational tool for training of future RAKT surgeons.

Single Port Robotic Kidney Autotransplantation: Initial Case Series and Description of Technique

PURPOSE

Minimally invasive kidney autotransplantation (KAT) has demonstrated reduced morbidity, however multiport robotic approach required patient repositioning and multiple sets of incisions. We present our initial series of single-port (SP) robotic KAT, ideal for multi-quadrant surgeries, and aim to evaluate feasibility and safety of the novel approach.

METHODS

Between 2018 and 2022, 8 consecutive patients underwent SP KAT using the DaVinci SP platform. Patient clinicopathologic variables and perioperative outcomes were recorded. Indications for KAT include complex or recurrent ureteral stricture, ureteral avulsion, and chronic visceral pain due to multiple etiologies.

RESULTS

All SP KATs were successfully performed without repositioning or conversion to open. Operative times ranged from 366 to 701 minutes, warm and cold ischemia times between 4 to 10 minutes and 86 to 209 minutes, respectively. Median hospital length of stay was 3 days. At a median of 13 months follow-up, latest postoperative GFRs were stable, ranging from +23% to -10%. There were no complications.

CONCLUSION

We demonstrate our single port, multiquadrant robotic kidney auto transplantation technique performed though a single incision further reducing surgical morbidity. All cases were completed successfully without conversion or loss of graft function. All patients reported resolution of flank pain and no radiological evidence of urinary obstruction on follow up.

Technical skills simulation in transplant surgery: a systematic review

Purpose

 Transplant surgery is a demanding field in which the technical skills of the surgeon correlates with patient outcomes. As such, there is potential for simulation-based training to play an important role in technical skill acquisition. This study provides a systematic assessment of the current literature regarding the use of simulation to improve surgeon technical skills in transplantation.

Methods

 Data were collected by performing an electronic search of the PubMed and Scopus database for articles describing simulation in transplant surgery. The abstracts were screened using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. Three reviewers analyzed 172 abstracts and agreed upon articles that met the inclusion criteria for the systematic review.

Results

 Simulators can be categorized into virtual reality simulators, cadaveric models, animal models (animate or inanimate) and synthetic physical models. No virtual reality simulators in transplant surgery are described in the literature. Three cadaveric models, seven animal models and eight synthetic physical models specific to transplant surgery are described. A total of 18 publications focusing on technical skills simulation in kidney, liver, lung, pancreas, and cardiac transplantation were found with the majority focusing on kidney transplantation.

Conclusions

 This systematic review identifies currently reported simulation models in transplant surgery. This will serve as a reference for general surgery and transplant surgery professionals interested in using simulation to enhance their technical skills.

Building a Low-Cost and Low-Fidelity Kidney Transplant Model: A Technical Report on the San Antonio Kidney Transplant Model

One of the most challenging aspects of the kidney transplant operation is performing vascular anastomoses in the confines and depths of the iliac fossa. General surgery residents need to be adequately trained in this skill to maximize their intraoperative experience during their transplant surgery rotation. While several kidney transplant models have been developed, they are limited in their ability to simulate the challenges of performing anastomoses at varying depths and in confined spaces. Furthermore, they may be expensive or require specialized equipment, such as three-dimensional printers, to build. In this technical report, we describe how to build a low-fidelity, low-cost, and portable kidney transplant model capable of simulating vascular anastomoses at varying depths. Our model can be easily replicated for less than 30 USD using materials available in local stores. It uses inexpensive and reusable parts, allowing trainees a high volume of repetitions.

3D-Printed Cold Preservation Device in Renal Autotransplantation for the Treatment of a Patient With Renal Artery Stenosis

Percutaneous transluminal angioplasty (PTRA) is a common treatment method for renal vascular disease (RVD). However, PTRA may not be effective in patients with abnormal vascular disease. Renal autotransplantation (RAT) has been used as an alternative therapy for these diseases. Restrictions due to intracorporeal kidney cold preservation and the renal function of intracorporeal RAT were not as well protected compared with open operation. We developed this technique of 3D-printed polylactide (PLA) cold jackets for laparoscopic complete intracorporeal RAT for the purpose of better protecting the renal function and determining the feasibility of this novel procedure. The procedure was successfully applied to a 51-year-old woman with bilateral renal artery stenosis. The operation time was 5 hours, and blood loss was 200 ml. The patient’s blood pressure remained constant throughout the operation, and the pressure was maintained at 120-140/70–90 mmHg without antihypertensive drugs 1 week after the operation. B-ultrasound showed that the blood flow signal of the transplanted kidney was normal and the boundary between the skin and medulla was clear. The patient was discharged 2 weeks after surgery. One year postoperatively, Doppler ultrasound of the autotransplant showed that the transplanted kidney was normal in size and shape. Radionuclide renal dynamic imaging revealed that the glomerular filtration rate (GFR) of the transplanted kidney was 36.9 ml/min. 3D-printed polylactide (PLA) cold jackets for laparoscopic complete intracorporeal RAT are a safe and effective method for the treatment of renal artery stenosis and represent a feasible method for preserving the renal function of severe renal artery stenosis patients; however, the technology is still at the exploratory stage and has room for further improvements.

Techniques of orthotopic renal transplantation in pigs. One donor to two recipients via inverted grafting

PURPOSE

Although transplanting two kidneys from a single donor to two recipients has some advantages, the right and left kidneys are not anatomically identical; thus, a surgical procedure considering the anatomical features of the donor kidneys is needed when transplanting them into the opposite renal fossae. Based on vast experience, the surgical details of pig orthotopic kidney transplantation from one donor to two recipients was reported.

METHODS

When the right kidney was transplanted to the left renal fossa, the graft was inverted upside down, not backwards, thus ensuring that the anteroposterior relationship of the renal vessels was maintained and anatomically natural vascular anastomosis could be performed.

RESULTS

Using this technique, we could have developed a pig experimental model that is safe and has a high success rate, even for researchers in the middle of their training. This technique of inverting the graft upside down was reported in human kidney transplantation to make vascular anastomosis easier.

CONCLUSIONS

In pig orthotopic kidney transplantation from one donor to two recipients, an anatomically natural vascular anastomosis could be performed via inverted grafting when the right kidney was transplanted into the left renal fossa.

Design and Validation of a Low-Cost, High-Fidelity Model for Urethrovesical Anastomosis in Radical Prostatectomy

OBJECTIVE

We sought to develop and validate a low-cost, high-fidelity robotic surgical model for the urethrovesical anastomosis component of the robot-assisted laparoscopic radical prostatectomy.

MATERIALS AND METHODS

A novel simulation model was constructed using a 3D-printed model of the male bony pelvis from CT scan data and silicone molds to recreate the soft tissue aspects. Using a da Vinci Si surgical robot, urology faculty and trainees performed simulated urethrovesical anastomosis. Each participant was given 12 minutes to complete the simulation. A survey established face validity, content validity, and acceptability. Simulation runs were evaluated by three blinded reviewers. The anastomosis was graded by two reviewers for suture placement accuracy and anastomosis quality. These factors were compared with robotic experience to establish construct validity.

RESULTS

Twenty participants took part in the initial validation of this model. Groups were defined as experts (surgical faculty), intermediate (fellows and chief residents), and novices (junior residents). Likert scores (1-5 scale, top score 5) examining face validity, content validity, and acceptability were 3.49 ± 0.43, 4.15 ± 0.23, and 4.02 ± 0.19, respectively. Construct validity was excellent based on the model's ability to stratify groups. All evaluated metrics were statistically different between the three levels of training. Total material cost was $2.50 per model.

CONCLUSIONS

We developed a novel low-cost robotic simulation of the urethrovesical anastomosis for robot-assisted radical prostatectomy. The model discerns robotic skill level across all levels of training and was found favorable by participants showing excellent face, content, and construct validities.