challenging in these conditions. Starting with dis­section from the perineum seems to offer advan­tages, by avoiding distal cross- stapling in a narrow pelvis. The use of laparoscopic staplers in this situ­ation is difcult as multiple staple rings across the low rectum increase potential for anastomotic leak [23]. The potential anastomotic benets of a transanal approach have been challenged by the recent publication of the International Registry in which the number of low anastomosis and anasto­motic leak rate was concerning [24, 25].

The signicant rate of taTME-related urethral injury occurs at the posterior wall of the pre­prostatic urethra in male patients with a distal anterior rectal cancer (within 3 cm of the anal verge). Atallah [36] has observed in his North American Training Program on taTME that approximately 20% of cadaveric trainees (all with considerable rectal cancer experience) will inadvertently mobilize the prostate and enter the incorrect plane, underscoring the importance of adequate training in this technique, which approaches the rectum from an unfamiliar van­tage point. Other cautionary points during taTME include meticulous attention to the autonomic nerve plexi [37] and other anatomic structures detailed in other chapters.

With the patient under general anesthesia, a urinary catheter is inserted, and the patient is placed in the lithotomy position with the use of stirrups. Digital examination and rigid proctos­copy are performed to conrm the tumor location. Abdominal access is achieved via Veress needle, which is inserted in the left upper quadrant and the abdomen, and CO2 insufation commences to an average pressure of 12mmHg. Robotic 8-mm trocars are next inserted in the right upper quad­rant (12–15mm and 8mm), right lower quadrant (two 8-mm trocars), and periumbilical region (12–15mm). The patient is positioned in a right tilt, and the peritoneal cavity is rst inspected through a standard laparoscope. After conrming the absence of signicant intra- abdominal adhe­sions and no evidence of distal tumor extension or cacinomatosis, the da Vinci Si robotic cart is docked from the patient’s left side (Fig. 44.1). Monopolar curved scissors are placed in Arm 1, a fenestrated bipolar grasper is placed in Arm 2, and a double-fenestrated grasper is used in Arm 3. A 30° 12-mm endoscope is employed. The splenic exure is rst taken down with dissection and

In 2017, the Flex® Robotic System and Flex® Colorectal (CR) Drive (MedRobotics, Corp. Raynham, MA, USA), a semi-robotic apparatus for colorectal surgery specically indicated for transanal endoluminal applications, as well as more radical resection (i.e., taTME), was approved by the US Food and Drug Administration (FDA). This platform has already been used in cadaver model and is currently under evaluation in a clinical trial [58]. The exible effector arms measure only 3.5mm, but are not robotic assisted, which is a limitation of the current technology. Other limitations include suturing at ranges beyond 15cm, needle delivery, and retrieval, and the process of suturing itself can sometimes be encumbered by the Flex® Robot’s convolution throughout the sigmoidal bends.