**3. The robotic approach**

Robotic surgery comes to replace the disadvantages of open surgery and many of those found in laparoscopy. It must be said from the beginning that we are not talking about a robotization of the surgical act, but about the fact that between the surgeon and the patient there is a high performance computer, which allows on the one hand a much finer surgery, with additional attention to detail. The disappearance of the tremor, with instruments that have 7 degrees of freedom, which make possible the access in the narrow spaces, and on the other hand allows the integration of an augmented reality by combining CT, MRI images, on the work screen. And we are talking about 3D images in which there is the possibility of using immunofluorescence with indocyanine green, so as to further visualize the vascularity or lymph node tissue that must be highlighted for a high quality oncological surgery. Fine tissues such as hypogastric nerve plexuses with a special role in maintaining potency are much better preserved when using robotic surgery in rectal cancer, and even more so in the case of large tumors or obese people with narrow pelvis.

This translates into a lower conversion rate, a reduced hospitalization, an easier learning curve and the ability to operate in confined spaces. Achieving a learning curve, which is half of that required for laparoscopy, requires the surgeon to master three unique concepts of robotic surgery, as outlined by Bokhari et al.: replacement of visual cues on tension and tissue manipulation instead of tactile feedback; aligning the robotic arms and trolley while operating remotely on the console, thus minimizing external collisions [22].

A recent retrospective study of 732 patients analyzing long-term oncologic outcomes using tilt score matching showed comparable survival between robotic and laparoscopic TME. In multivariate analysis, robotic surgery was a significant better prognostic factor for overall survival and cancer-specific survival [23]. The most recent and largest randomized clinical trial of laparoscopic or robotic approach for patients with rectal adenocarcinoma (ROLARR) demonstrated comparable oncological results [24].

With all the advantages that the robotic system has, there are also a number of disadvantages [25–27]. Of these, the absence of tactile sense is an important disadvantage. This is an important step in the learning curve so that you can get used to manipulating the tissues without over-pulling them and coordinating the pressure exerted by the instruments on the tissues only through the eye [28].

Another disadvantage was considered too long docking time, but this was shortened by the new generation of Da Vinci Xi robotic systems. After a learning curve of about 20 interventions, the docking time stabilized at a maximum of 15 minutes.

Another negative element that was attributed to the robotic system was also the fact that in the case of an intraoperative bleeding that would require conversion to the open approach, the time required to undo the robot may be too long. Today, however, with the improvements made to the robot, the undocking is done in a maximum of one minute [29].

Another difficulty in using robotic surgery rectal addressed is the possibility of collision between the robot arms.

The cost is a major disadvantage of the robotic approach in terms of rectal surgery. There are studies that show that robotic surgery is significantly more expensive than laparoscopic surgery. Baek et al. reported that hospital charges are 1.5 times higher for the robotic group compared to a laparoscopic group (USD 13,644 vs. USD 9,065, P < 0.001) [30]. On the other hand, Quijano et al. publishes a study on the cost-effectiveness comparison between the robotic and laparoscopic approach in rectal surgery. Even if the cost of hospitalization is really higher for the robotic approach, if we talk about quality adjusted life years then it seems that the robotic approach is superior to the laparoscopic one [31].

Disadvantages of robotic surgery include: increased operative time, lack of haptic feedback, remote location of the surgeon away from the operating table, inability to perform abdominal surgery in several quadrants and the cost of technology [25–27].

#### **4. Indications of the robotic approach in rectal cancer**

Patient selection is essential for surgeons at the beginning of the learning curve. The ideal candidate is the patient with a tumor located in the middle or upper rectum, in stage I or II, patient without previous abdominal interventions and with a normal BMI. With the gain of experience, the robotic approach proves its advantages exactly in cases where laparoscopy would have had relative contraindications. This includes obese, male patients with a narrow pelvis with tumors located in the lower rectum. In these cases the dissection can be performed successfully in small spaces, with articulated instruments, the quality of the total excision of the mesorectum to be superior even to the open approach. The three-dimensional view increased visibility allows a more precise visualization of the hypogastric nerve plexuses and their preservation as an extremely important objective in maintaining urinary and sexual functions.

#### **5. Preoperative preparation**

Preoperative preparation for colorectal robotic surgery is no different from laparoscopic surgery except in one significant way. Unlike laparoscopy, the surgeon is seated at the console, away from the operating table. That is why the role of a well-trained team is extremely important. The team ensures the correct handling of the robot's arms, in order to avoid the collision between the robot's arms during the intervention. The assistant surgeon will always be the one who will ensure the retraction of the structures to be dissected, will change the robot's instruments when necessary. There are also times during the operation when he will insert a stapler through which he will section the intestine, sometimes vascular sealing instruments or clips. Perhaps the most important role of the team is to be able, in case of need, to undock the robot in a very short time. That is why the permanent training of the team is very important.

Minimally invasive colorectal cancer surgery has also led to the widespread introduction of Enahenced Recovery After Surgery (ERAS) protocols. Within these protocols, an important role is represented by the preoperative preparation

#### *The Robotic Approach in Rectal Cancer DOI: http://dx.doi.org/10.5772/intechopen.100026*

of the patients who are to have a colorectal intervention. The benefits are obvious in terms of reducing hospitalization, costs, postoperative infections, postoperative pain, facilitating faster resumption of intestinal transit and avoiding nausea or postoperative vomiting [18, 32].

As a preoperative preparation, an essential stage is represented by the patient's counseling, the discussion regarding the intervention, the postoperative evolution and the discharge criteria and the establishment of its compliance for the achievement of the criteria included in the protocol. The discussion is also important for the preparation of a possible stoma, either temporary protective or permanent, followed by marking the place of the future stoma. Avoiding a long period of fasting is important, the recommendation being to maintain a light fluid regime up to 2 hours before general anesthesia. The carbohydrate diet is encouraged in nondiabetic patients in an effort to reduce the increase in insulin resistance by starvation to which will be added the operating stress [33]. There is still controversy about intestinal preparation. The recommendation is for both mechanical and oral antibiotic preparation, which is associated with a decrease in the morbidity rate, including a decrease in the rate of infection in the incisions associated with the intervention [34]. Prophylaxis of deep vein thrombosis is achieved by preoperative administration of low molecular weight heparins. An important element is the multimodal analgesia that begins preoperatively by administering oral analgesics, along with antiemetics so that together with the measures taken intraoperatively to make an easy transition to the postoperative period and thus return the patient to normal much faster [35]. All will contribute to a reduced hospitalization with all the advantages that derive from it, including from the oncological point of view the faster initiation of the adjuvant treatments.
