Robotic single-port surgery for kidney and upper urinary tract cancers

6.1 Background

Gettman et al. described the first cases of single site laparoscopic renal surgery in a porcine model performed via transvaginal approach. This was a natural orifice transluminal endoscopic surgery (NOTES). The first patients who then underwent laparoendoscopic single site (LESS) renal surgery were in 2007 via three adjacent umbilical ports with articulating instruments. As the umbilicus represents an embryonic natural orifice, this was characterized as E-NOTES. These cases consisted of simple and radical nephrectomies for nonfunctioning kidneys and central renal mass not amenable to partial nephrectomy. Internal and external collisions were problematic and, with the exception of several high volume institutions, wide-spread adoption was not seen due to the technical difficulty and high degree of expertise required. The multiport robotic platform was then utilized for the first robotic single-port renal surgery by Kaouk et al. for pyeloplasty and radical nephrectomy via transumbilical approach and a multichannel gel port. This approach, described as robotic-LESS (R-LESS), experienced similar limited utilization to LESS primarily by a few high volume institutions due to the limited mobility, collisions, and challenges of incorporating the fourth robotic arm. In addition, there were reports of lower rates of optimal surgical outcomes. For example, for partial nephrectomy, the trifecta of warm ischemia <20 minutes, negative surgical margins, and the absence of surgical complications was achieved in only 25.6% of patients compared with 42.7% of patients undergoing multiport partial nephrectomy. Nevertheless, the practitioners of LESS surgery reported shorter convalescence, less pain, and improved cosmesis thereby allowing them to persevere through the technical challenges.

The Da Vinci SP was the first purpose-built single-port robotic platform utilizing a multichannel port and articulating endoscope allowing a total of four robotic arms. The feasibility of performing radical and partial nephrectomy with this platform was first described in three cadaver studies. Since its commercial release in 2019, multiple institutions and surgical groups have adapted this platform for renal surgery including robotic nephrectomy, partial nephrectomy, pyeloplasty, ureteral reconstruction, and nephroureterectomy in both transperitoneal and retroperitoneal approaches.

In our experience with this modality, there is decreased postoperative pain allowing earlier hospital discharge. While there is a distinct learning curve with the SP platform, it is steeper and faster than that of prior single site renal surgeries particularly among those already experienced with robotic renal surgery.

6.2 Positioning

For transperitoneal cases, it is our preference to position patients in a full 90° lateral decubitus position. An axillary roll is placed to protect the brachial plexus. Upper arm is positioned on an arm rest nearly parallel with the lower arm. Kidney rest and bed flexion are not utilized. For retroperitoneal cases, however, bed flexion is utilized to maximize the working space between the lower costal margin and iliac crest. Complete lateral decubitus facilitates gravity-assisted colon mobilization. For nephroureterectomy, it may be beneficial to place the bed in slight Trendelenburg so as to bring the bowel out of the pelvis for the distal ureteral/bladder cuff dissection.

6.3 Single-port site

Using the Hasson technique, a 2.5 fascial opening is made for the port site. The cannula with blunt obturator is placed directly through this. Alternatively, the incision can be extended slightly to accommodate adjacent additional ports and instruments. These can be placed directly through the same incision or through a wound protector with cap such as the GelPORT (Applied Medical, Rancho Santa Margarita, CA) as seen in Fig. 6.1 .

Placing the port site at the umbilicus provides a muscle sparing incision that can be extended vertically for specimen extraction as well as partially concealed by the natural contour of the navel. This is generally sufficient for most renal cases. One specific considerations of the SP system is the 10 cm working distance needed from the port site and target anatomy. If this distance is too short then the instruments are unable to fan out and utilize their complete range of motion. This is more common in patients with a small body habitus or with large lower pole tumors approached retroperitoneally. It can be managed with two solutions. One is to move the port site further away from the target anatomy but this is not feasible with large lower pole tumors during the retroperitoneal approach. The other, dubbed “floating dock,” is where the seal of the wound protector system, through which the trocars are placed, is moved further from the skin level.

The assistant may be placed adjacent to the primary cannula. However, they will be “handcuffed” to the primary trocar and limited in their movements. Actions such as suture placement and removal may be performed but more complex tasks such as suction and retraction are less feasible through this approach. A “+1” assistant port can be placed through a separate skin incision; however, this no longer becomes truly single port. This can be avoided with the use of a flexible suction catheter controlled by the surgeon such as the purpose-built Remotely Operated Suction Irrigation System (ROSI, VTI, Nashua, NH), or a nasogastric tube or something similar as seen in Fig. 6.2 . This is generally placed through the adjacent assistant port through the same incision or through the fourth port on the main cannula if only three instruments including the camera are needed.