Single-port robotic surgery for kidney transplantation—rationale and conceptualization
During the past decade, many centers adopted robotic-assisted kidney transplantation (RAKT) as an alternative minimally invasive procedure for kidney transplantation. A significantly higher rate of wound-related complications with open surgery has been the main driving force of the application of minimally invasive procedures for kidney transplantation. Large incisions used for wide exposure during conventional open kidney transplantation, particularly in the setting of immunosuppression, in patients with obesity diabetes, or other comorbidities are at a high risk of wound infection, dehiscence, and hernia. These complications would negatively affect patients’ postoperative morbidity and recovery as well as the graft outcome.
With the application of minimally invasive surgery for kidney transplantation, less wound complications and a quicker recovery could be expected. A systematic review and meta-analysis of data comparing minimally invasive versus standard open technique for kidney transplantation showed comparable graft and recipient survival outcomes with significantly less wound-related complications (0 vs 16%–19% vs 0%) with the application of minimally invasive surgery. Patients who underwent laparoscopic/ robotic kidney transplantation experienced less postoperative pain, less need for analgesics, and a faster recovery. These findings were confirmed in 2021 by Ahlawat et al. who compared the outcomes of RAKT ( n =126) versus open KT ( n =378). Ischemia time was longer with the robotic approach, however, after a median follow-up period of 2 years, graft outcomes were comparable. Patients who underwent RAKT had less intraoperative blood loss, lower rates of wound complications (0% vs 4%). Overall, these patients experienced a less morbid procedure with less postoperative pain and the need for narcotics.
Obesity may independently be associated with poor graft outcomes and a higher rate of wound complications after open KT. However, in patients who underwent RAKT, similar rates of wound-related complications (2% vs 1.4%) and graft survival were shown in obese versus nonobese recipients.
With the application of single-port (SP) robotic surgery for various urological procedures at many centers, it has been shown that atleast for radical prostatectomy, SP robotic approach would be associated with a shorter hospital stay, less postoperative pain, and quicker recovery compared to conventional multiport robotic approach. Therefore the use of a SP robotic platform may be a step forward to perform kidney transplantation even less invasive.
Single-port robotic renal transplantation—implementation of an innovative procedure
Understandably, SP robotic renal transplantation is an innovative and complex procedure. For the implementation and development of this procedure, the authors recommend following the five-step process for the development of new surgical procedures (IDEAL Model: www.ideal-collaboration.net/framework model describes a five-stage process that should be passed to implement a new surgical innovation):
Preclinical (feasibility) step (Phase 0): Practicing and standardizing the procedure in the cadaveric laboratory are highly recommended before the clinical implementation of this innovative approach. This preclinical step is vital in minimizing errors and gaining proficiency in SP RAKT as a new procedure. This preclinical step is also very helpful in assembling and orienting motivated well-versed teams of anesthesiologists, operative room staff, and surgeons skilled in robotic surgery and open kidney transplantation.
Innovation, (Phase 1) (Innovation): In this phase, the initial concept of a new procedure is shown by a few surgeons and applied to very few patients. To our knowledge at present time, SP RAKT is still in this phase.
Development (Phase 2a): More surgeons and innovators demonstrate the safety, feasibility, and reproducibility of the new surgical procedure on more patients.
Exploration (Phase 2b): Diffusion of the procedure to the community by sharing the experiences of many surgeons. This would be helpful in the development of a patient registry and database.
Assessment (Phase 3): Conduction of clinical trials to evaluate the clinical efficacy and cost-effectiveness of the new procedure compared to standard of care.
Long-term studies (Phase 4): For assessment of long-term outcomes and quality assurance.
In our initial experience, we applied SP RAKT in two different scenarios; (1) Adult patients with end-stage renal disease ( n =6) and (2) Adult patients who underwent kidney autotransplantation, (ipsilateral SP robotic nephrectomy and kidney transplantation) ( n =3).
We excluded patients with complex vascular graft anatomy requiring more than one vascular anastomosis and those requiring a native nephrectomy. Preoperative noncontrast computerized tomography should be used to evaluate the anatomy and configuration of external iliac arteries (with regards to the presence of significant atherosclerotic plaques).
In our initial experience, we used both living and deceased donors. Deceased donors were brain dead donors with a high Kidney Donor Profile Index (>50%), with minimal (if any) aortic plaque, and without any vascular abnormalities.
As discussed later, both transperitoneal or extraperitoneal approaches can be used to prepare recipients’ vasculature and transplant the kidney.
Positioning, access and port placement
The patient is in a supine position with 15 degrees Trendelenburg and 30 degrees rotated to right lateral position. For the transperitoneal approach, the peritoneal cavity is entered directly via a 5 cm midline periumbilical incision ( Fig. 9.1 ). Alternatively, the extraperitoneal approach can be elected and through the same incision, the retroperitoneal space is developed by the medial reflection of the peritoneum for direct access to the iliac vessels.
Then a large GelPOINT (Applied Medical, Rancho Santa Margarita, California, United States) system is placed in the wound as the entry point of robotic arms and for wound retraction. The GelPOINT system is also used as the entry point for kidney graft.
The SP trocar and a 12 mm assistant port are inserted through the GelSeal cap, and after establishing the pneumoperitoneum, the SP robot is docked ( Fig. 9.2 ). With the transperitoneal approach, the cecum and right colon will be medialized to expose the external iliac vessels. However, as mentioned above, with an extraperitoneal approach, direct access to the external iliac vessels is possible. The external iliac artery and vein as well as the right anterolateral aspect of the bladder are dissected and prepared for grafting ( Fig. 9.3 ).
Kidney benching (extracorporeal graft preparation)
After defatting the kidney graft, its pedicle is fully dissected into the hilum and all small vascular branches are tied. Euro-Collins solution is used to flush the renal artery till the efflux is clear. A surgical glove is used as a jacket to wrap the graft in; this would facilitate intracorporeal manipulation with the robotic instruments. To prevent graft torsion during intracorporeal suturing, the upper pole and the posterior surface of the graft are marked with silk stitches on the glove jacket. Similarly, to prevent any vascular torsion, the posterior surface of the renal artery and vein is marked with a marking pen ( Fig. 9.4 ).