Single‐port extraperitoneal robotic kidney transplantation: early experience of novel technique

There has been an increased shift in the adoption of robotic surgical platforms across various surgical specialties over the last two decades including kidney transplantation (KT) given proven benefits with enhanced recovery, decreased morbidity, and similar functional outcomes compared to the open approach [1, 2]. However, robot-assisted KT (RAKT) is commonly performed via the transperitoneal approach compared to the open extraperitoneal (EP) approach. The novel purpose-built single-port (SP) robotic platform (Intuitive Surgical, Sunnyvale, CA, USA) has been widely adopted for various urological procedures since 2018 including initial pre-clinical reports of SP KT [3], as well as the initial clinical experience with SP KT and SP kidney autotransplantation in prior studies [4, 5]. Appreciating the potential benefits of regionalised surgical access possible with the EP approach, we have adopted it for KT in our practice since the early report. A retrospective review was performed to identify all patients who underwent SP EP-KT between August 2020 and January 2023. All patients aged >18 years with end-stage renal disease diagnosis were considered candidates for SP KT. Exclusion criteria for SP EP-KT included calcifications in the external iliac artery, prior transplant on the ipsilateral side, and large donor kidney (>14 cm). The primary outcome of this study was to demonstrate the safety and feasibility of the surgery defined as successful completion of the transplant procedure without any conversion, abortion of procedure, or postoperative graft loss. Secondary outcomes reported include perioperative outcomes including estimated blood loss (EBL), total operative time (OT), revascularisation time (RT), and postoperative renal function assessment. Patient clinical demographics and postoperative outcomes data were collected prospectively. All procedures were performed under general anaesthesia. The patient was placed supine, with the arms out and the bed slightly tilted to the left side and minimal Trendelenburg position. A 5-cm infra umbilical midline incision was made and extended through the subcutaneous tissue and abdominal fascia. After the rectus muscles were split in the midline, the EP space was created by reflecting the peritoneum using blunt dissection and electrocautery. After the development of an adequate EP space, the inner wound retractor ring for the large incision da Vinci Access Kit was placed through the incision into the EP space (Fig. 1A). The access port was assembled, the EP cavity was insufflated to a pressure of 12 mmHg, and the SP robot was docked towards the ipsilateral pelvis using the floating dock technique with the camera-up orientation [6] (Fig. 1B). In preparation for the anastomoses, the external iliac vessels were isolated, exposed, and cleared of the adventitia robotically. Vessel loupes were applied around the external iliac vessels to facilitate handling. Once an adequate length of the iliac vessels were obtained, the SP robot was undocked, and the donor graft wrapped in a modified sterile surgical glove was introduced into the EP space (Fig. 1C). Insufflation was re-initiated, and the robot was re-docked. Two robotic bulldog clamps were placed on the proximal and distal aspects of the external iliac vein. A venotomy was sharply made on the anterior aspect of the vein in between and flushed with heparinised saline. With the kidney oriented medially, the renal vein was then anastomosed in an end-to-side running fashion using expanded polytetrafluoroethylene CV5 sutures (Fig. 1D). We performed a similar external iliac arteriotomy for renal arterial anastomosis and the renal artery was anastomosed similarly to the venous anastomosis (Fig. 1E). The venous and arterial anastomoses were tested sequentially with the removal of the bulldog clamps. Once the vascular anastomoses were complete, the kidney was lateralised above the psoas. The bladder was distended with saline, and a cystotomy was sharply made in the bladder dome. A refluxing ureteroneocystostomy was performed in a water-tight running fashion over a pre-placed 4.6-F by 14-cm JJ ureteric stent using bidirectional running 4-0 polyglactin 910 sutures. The fascia and skin were closed after checking haemostasis (Fig. 1F). Between 2020 and 2023, 40 patients successfully underwent SP EP-KT. The complete patient demographics and perioperative outcomes are summarised in Table S1. The median (interquartile range [IQR]) age and body mass index of the patients in the study were 54.45 (46.8–60.3) years and 32.1 (29.8–37.4) kg/m2, respectively. Of note, 42% of the patients in our study had prior abdominal surgery and two patients (5%) had a previously failed kidney transplant. The median (IQR) preoperative creatinine of 555.16 (373.06–824.79) μmol/L (6.28 [4.22–9.33] mg/dL). The median (IQR) OT was 262 (218.3–314.3) min and the median (IQR) RT was 53 (44.5–65) min in our series. The initial 11 cases required an additional port for the assistant and aortic punch placement for arterial anastomosis, which we transitioned away from as we progressed through the learning curve. The median EBL in our series was 50 mL. While most procedures were completed successfully using the SP platform, one case required conversion to an open surgical approach via an extension of the midline incision given poor arterial pulsations after completion of vascular anastomosis with a dusky colour of the renal parenchyma. The patient had an uneventful postoperative recovery without significant clinical sequelae or graft failure. The median hospital stay in our series was 2 days and the median creatinine at discharge was 247.52 μmol/L (2.8 mg/dL). There were 10 postoperative complications (25%) and nine re-admissions (22.5%) within 90 days of the respective surgery. The major postoperative complications as determined by the Clavien–Dindo classification as Grade ≥III were reported in five patients (12.5%) in the first 90 days. At a median (IQR) follow-up of 7 (6–18.5) months, there was no evidence of graft failure and patients remained dialysis-free postoperatively. The patient's renal function progressively improved over time with a median (IQR) creatinine of 132.60 (97.24–150.28) μmol/L (1.5 [1.1–1.7] mg/dL) at the latest follow-up. The first robotic KT was demonstrated by Giulianotti et al. [7] in 2010 but the initial adoption has been quite slow until the last 5 years, with more focus shifting towards the RAKT. A recent publication by Pecoraro et al. [8] about an audit of European surgeons’ practice performing RAKT showed an overall increase from 6% in 2017 to 11% in 2022 at the respective tertiary referral transplant centres. With the introduction of the SP platform, regionalisation of robotic surgery was possible with more interest towards EP approaches to urological surgeries with proven benefits including decreased patient morbidity, especially minimal postoperative pain, early discharge, and low narcotic usage. With this growing interest, we explored the idea of an EP-KT utilising the SP robot. Here, we demonstrate the safety and efficacy of a novel SP EP-KT technique. The procedure is associated with overall reduced morbidity and decreased hospitalisation times without any detrimental impact on graft function after surgery in our series. None. Jihad Kaouk is a speaker for Intuitive Surgical Inc. and is a consultant for MethodAI, VTI, and EndoQuest Robotics. The remaining authors have no conflicts of interest to disclose. None. Table S1. Patient demographics and perioperative outcomes. Video S1. We demonstrate our single-port extraperitoneal kidney transplant step-by-step technique in a 50-year-old female with a history of end-stage renal disease, undergoing haemodialysis. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.