Proper port placement is crucial since the current da Vinci^® system is rather bulky and requires sufficient room between arms, not only to avoid external collision but to also maximize internal movement.

Six ports are used, namely, one 12-mm camera port, four 8-mm robotic working ports, and one 5-mm port for the assistant. After pneumoperitoneum is achieved by either an open technique or a Veress needle, a 12-mm trocar is placed through an incision around the umbilicus for the robotic camera. Since there is an ideal distance (about 15 cm) between the scope and the target anatomy, the camera port should be shifted a few centimeters lateral to the umbilicus if the patient has a small body size. The intra-abdominal pressure is maintained at 8–12 mmHg. The first da Vinci^® 8-mm port is placed on the right lower quadrant (RLQ), approximately at the McBurney point. The second 8-mm robotic port is inserted in the right upper quadrant (RUQ), mostly on the midclavicular line (MCL). The third 8-mm port is placed in the left upper quadrant (LUQ), approximately 1–2 cm above the camera port at the crossing of the MCL. The fourth port is inserted in the left lower quadrant (LLQ), approximately one to two centimeters lateral to the MCL. These four ports are used for the robotic instrument arms and are separated from each other by at least 8 cm. To allow the assistant access, a 5-mm trocar is placed in the right flank area, near the anterior axillary line at the umbilicus level. This is used for suction/irrigation, clipping of vessels, and retraction of tissues. The port placement is shown in Fig. 19.2. The port position can be altered according to the patient’s physique. However, there are several principles when placing the trocars. Since the anterior iliac spine and the 12th rib are fixed in position, the RLQ port should always be placed first at McBurney point, and then the RUQ port is positioned close to the right costal margin. The camera port is placed around the umbilicus in order to be positioned at the same distance from the RLQ and RUQ ports. If possible, it is better to have a longer distance and a wider angle between the two right trocars, as shown in Fig. 19.2.

The first step of robotic LAR involves optimizing exposure and exploring the abdominal cavity laparoscopically. A zero-degree robotic camera or a conventional laparoscope is used. The whole abdominal cavity is inspected carefully for metastatic disease. The operating table is tilted to provide initial exposure of the operating field, by shifting the small bowel loops into the RUQ (Fig. 19.1). In general, inadequate exposure, which makes robotic surgery difficult, is mainly caused by distended small bowel with fatty mesentery. The right-sided omentum should be repositioned over the liver to create more space in the RUQ, then to maximally displace the small bowels to this space. This step is achieved with conventional laparoscopic instruments.

Once initial exposure has been achieved, the patient cart is brought in for docking. The patient cart is positioned obliquely at the LLQ of the abdomen along the imaginary line from the camera port to the left anterior superior iliac spine. The robotic arms are then docked to the trocars. When using all three da Vinci^® instrument arms, setup joint of the camera arm should be positioned towards the patient’s side to allow space for the instrument arms ② and ③. Before starting the console activity, the robotic arms should be adjusted to create maximal space in between, shown as a well-spread fan (Fig. 19.3).

Initially, the mesocolon over the IMA is retracted upwardly with the Cadiere forceps. The peritoneum around the base of the IMA is incised and dissected with monopolar scissors. The periaortic hypogastric nerve plexus is carefully preserved. The IMA is divided near the root with Hem-o-lok^® clips (Weck Closure System, Research Triangle Park, NC, USA) (Fig. 19.4). The inferior mesenteric vein is identified by dissecting superiorly toward the ligament of Treitz and is divided near the inferior border of the pancreas.

The medial dissection continues laterally until the left colon is separated from the retroperitoneum and superiorly over the pancreas until the lesser sac is entered. The left gonadal vessels and the ureter are identified and preserved. Lateral detachment is initiated along the white line while the sigmoid colon is retracted medially by the assistant. Lateral countertraction by the instrument arm ② facilitates safe dissection. The lateral dissection continues cephalad to the middle portion of the descending colon. Splenic flexure is mobilized if necessary to achieve a tension-free anastomosis. The transverse mesocolon is opened just above the body of the pancreas to enter the lesser sac. Dissection of the transverse mesocolon continues towards the distal transverse colon and the base of the descending colon. Then omentum attached to the transverse colon is then dissected in the avascular plane, beginning from the middle third of the transverse colon. The renocolic and splenocolic ligaments are divided and the splenic flexure is fully mobilized. During splenic flexure mobilization, only robotic arms 1 and 3 are aligned to minimize external collision; however, the assistant can contribute significantly by inserting his/her instruments through the remaining ports. If complete splenic flexure mobilization is not feasible with whatever reasons, it can be performed lastly, after completion of robotic pelvic dissection.

The robotic instruments of the RUQ and LUQ ports are dedocked and redocked to the LUQ and LLQ ports, respectively. Before beginning the console activity, the robotic arms should again be adjusted to create maximal space in between, shown as a well-spread fan. The assistant then uses the RUQ port to retract the rectosigmoid cephalad and the 5-mm assistant port for suction and/or retraction (Fig. 19.5). Therefore, five instruments are used in the operative field (three robotic and two handheld), maximizing assistance by using both hands for TME. The assistant applies cephalic traction using a cotton tie around the sigmoid colon. The robotic Cadiere grasper retracts the rectum anteriorly, thus exposing the plane between the mesorectal fascia and the inferior hypogastric nerves. The avascular space between the mesorectal fascia and the presacral fascia is sharply dissected with monopolar scissors. The inferior hypogastric nerves and, distally, the pelvic nerve plexus are identified and preserved. Further posterior dissection down to the levator ani muscle is approached from the left lateral plane, while the rectum is lifted up using the Cadiere forceps. The left lateral dissection is performed while the rectum is drawn to the right side by the assistant. Then, the right lateral dissection is completed in the reverse order used for rectal retraction. Finally, anterior dissection is performed by incising the peritoneal reflection. Sharp dissection is continued until the correct plane between the rectum and vagina/seminal vesicles/prostate is achieved. The rectum is retracted downward with the instrument attached to robotic arm 3 (Maryland grasper), and the vagina/prostate is counter-retracted upward with the instrument attached to robotic arm 2 (Cadiere forceps). During the pelvic dissection stage, the assistant uses the RUQ port as well, therefore maximizing assistance by use of both hands.

An effective method to enhance the exposure of the pelvic cavity in postmenopausal women is suspension of the uterus from the abdominal wall using a suture (Fig. 19.6). A similar suspension can be made with a suture around the thick, fatty peritoneum to retract the bladder in obese patients.

Robotic stapling devices are currently unavailable. Therefore, after adequate TME down to the pelvic floor, undocking of the robotic arms, movement of the patient cart away from the operating table, and a switch to a laparoscopic setting are necessary for rectal transection using an endostapler. The remaining steps are performed using conventional laparoscopic methods. After extending the robotic 8-mm port on RLQ to a 12-mm port, an articulating linear endostapler loaded with a gold cartridge (4.2 mm) is used via the RLQ port. A distal rectal washout is then performed, and the rectum is divided using an endostapler to achieve at least a 2-cm distal margin. The specimen is delivered through a small incision at the LLQ port, and the wound is covered with an impermeable protector. Transection of the proximal bowel is performed extracorporeally. The anastomosis is performed intracorporeally using a standard double stapling technique. A diverting ileostomy is selectively constructed in cases with air leaks, incomplete doughnuts, preoperative radiation, extreme difficulty in pelvic dissection, or coloanal anastomosis.

Recently, we modified our technique to maximize the advantages that we could gain from using a robotic system. After TME, the instrument arms ① and ③ are dedocked; however, the robotic camera and the instrument arm ② are left in place to provide stable and constant upward traction with Cadiere forceps and a stable camera view (Fig. 19.7), both of which make it easier to apply and fire the endostapler.

Once a surgeon’s preference is established, it is hard to adapt a new surgical approach to his/her practice. Because most experienced laparoscopic colorectal surgeons feel quite comfortable when they perform laparoscopic mobilization of the left and sigmoid colon, they don’t contemplate the introduction of a totally robotic procedure into their practice.

However, a hybrid technique may have some limitations. First, it has no advantage from robotic technology, neither at the phase of IMA dissection nor at the phase of splenic flexure mobilization. Robotic third arm controlled by the surgeon can provide effective lifting up of IMA. Because not only the pelvic nerves but also the periaortic nerves are important for voiding/sexual functions [14, 15], we believe that robotic dissection around the IMA pedicle is a critical step. The three-dimensional magnified view and EndoWrist function could be helpful in identifying and preserving the periaortic hypogastric nerve plexus. Also, these technical advantages could enable easier mobilization of a difficult splenic flexure than conventional laparoscopic approach.

Second, it may be inconvenient to perform an intraoperative colonoscopic examination because the bulky patient cart is located between the patient’s legs. Under the hybrid setting, it is impossible to apply our modified stapling technique.

Unfortunately, it may be very difficult to demonstrate the clinical benefits of these potential advantages of totally robotic LAR. In the present situation in which more stringent scientific evaluations in the setting of multicentre, randomized clinical trials are required to verify the benefits of the robot-assisted rectal cancer surgery, it is far too early to talk about the superiority between the totally robotic and hybrid approach. Nonetheless, we should be concerned how we can maximize this advanced technology in every step of the procedure.

Very few limitations specific to fully robotic LAR exist. As shown in Table 19.1, the clinical outcomes of our fully robotic LAR technique are quite comparable with those of our laparoscopic counterpart or other series performed using hybrid technique. No intraoperative complication related to robotic vascular ligation and sigmoid colon mobilization was recorded. As the safety and feasibility of the various types of robotic colon surgery are already proven in previous studies, there is no issue arguing about fully robotic approach except longer operating time [1–4].