Robotic Anastomotic Technique

Abstract

The first robotic colectomy was performed 20 years ago. Since that time, the robotic surgery platform has made significant advancements and become increasingly prevalent in colorectal surgery. The da Vinci Xi system (Intuitive Surgical, Sunnyvale, CA) and technology such as integrated table motion has facilitated multiquadrant procedures.

Intracorporeal anastomoses (ICAs) have proven benefit in the literature, including decreased length of stay, decreased narcotic requirements, and lower rate of postoperative wound infections and hernias. Additional studies have shown a lower conversion to open rate in robotic surgery compared with laparoscopy. In this article, we will describe techniques for creation of robotic ICAs.

Laparoscopic colectomy has shown benefit compared with open resection, but is limited by the lack of articulation of the instruments and the two-dimensional view. ¹ Robotic surgery has attempted to add a more natural operative motion that can be confined into a narrow operative field, such as the pelvis, with a three-dimensional field of view. Trials are ongoing to compare laparoscopic to robotic surgery. However, it is unlikely that robotic surgery will be far superior to laparoscopy in terms of traditionally measured outcomes, such as length of stay, ileus, blood loss, infection rates, or patient morbidity. The benefit of robotic surgery is the ability to do a more complex version of laparoscopy in an ergonomically comfortable position. One particular benefit may be the completeness of mesenteric or mesorectal dissection. With increased articulation of the instruments, intact mesorectum is more common with robotic resection techniques. ² Additional benefit may be demonstrated in decreased conversion rates, but will be challenging to measure as some surgeons will not even attempt laparoscopy in a very complex case that would be attempted by a surgeon comfortable with the robotic platform. The benefits of robotics will have to be balanced against the significant cost of the platform. ³

One of the other main advantages of robotic surgery is the ability to perform intracorporeal anastomosis. Intracorporeal anastomosis requires less colonic mobilization and a decreased incision for specimen extraction since the bowel does not need to be exteriorized for anastomosis. The following article will highlight the considerations and set-up for robotic intracorporeal anastomosis.

Operative Considerations

We consider most patients candidates for robotic minimally invasive surgery in an elective setting. Many patients in the acute care setting will also benefit from a minimally invasive approach. Hemodynamic instability and inability to tolerate pneumoperitoneum are two contraindications to a robotic approach. A detailed history and physical with examination of prior surgical scars may influence approach for entry, port placement, and operative approach. Preoperative imaging may influence port placement (i.e., redundant transverse colon or a high splenic flexure). Patient factors such as prior operations and obesity should not be considered contraindications to robotic surgery. In fact, studies have shown a lower conversion to open rate compared with laparoscopy. ^{4 5 6}

Patient positioning is an important factor in successful completion of robotic colectomy. Our practice is to position patients undergoing right colectomy in the supine position with the table tilted right side up. For left-sided resections, the patient is positioned in lithotomy with steep Trendelenburg and the table tilted left side up.

In facilities where integrated table motion is available, the patient position can be changed to improve visualization or facilitate instrument reach without undocking the robot. Integrated table motion is particularly helpful when operating in multiple quadrants, such as splenic flexure mobilization and total abdominal colectomy. Otherwise, the robot may be undocked and the patient repositioned as needed to complete the operation. In the case of total abdominal colectomy, the robot may be docked for mobilization of the hepatic flexure, transverse colon, and splenic flexure and then rotated 180 degrees to complete mobilization of the ascending, descending, and sigmoid colon. Careful surgical planning can help minimize repositioning and increase efficiency.

Intracorporeal Anastomosis

Studies comparing intracorporeal and extracorporeal anastomoses in robotic surgery have shown several benefits. Akram et al showed decreased time to flatus and bowel movement in patients who underwent robotic right colectomy with intracorporeal anastomosis. ⁷ Al Natour et al showed decreased hernia rates in patients undergoing robotic left colectomy with intracorporeal anastomosis compared with extracorporeal anastomosis. ⁸ A recent multicenter prospective trial by Cleary et al showed that operating time was longer for patients undergoing both laparoscopic and robotic intracorporeal anastomoses. However, patients with intracorporeal anastomoses had significantly shorter time to flatus, bowel movement, and hospital length of stay. Patients undergoing extracorporeal anastomoses had extraction incisions in the midline, while 99% of patients with intracorporeal anastomoses had off-midline extraction sites. There were no significant differences in rate of complication between the two groups. ⁹

Anastomotic Technique

Right Colectomy

The trocars are placed in a linear fashion along the left abdomen ( Fig. 1 ). A 12-mm trocar is placed at arm 4 to accommodate the stapler. Alternatively, the stapler can be placed at arm 1 to allow for a Pfannenstiel extraction, although the stapling angle is more challenging. The mesenteric dissection and division of the mesentery is achieved intracorporeally, and aided with the use of an energy device. The bowel is then transected intracorporeally. Because the transverse colon does not have to reach outside the abdominal cavity, mobilization of the transverse colon beyond the planned transection point is not necessary. Once the bowel has been transected, the ileum is approximated to the colon. Our preference is to perform an isoperistaltic anastomosis. A stay suture may be placed to facilitate creation of the anastomosis. An enterotomy and a colotomy are made with scissors. Care should be taken that the colotomy is at least 6 cm distal to the transverse colon staple line to ensure an adequate length for the anastomosis. The enterotomy can be placed just proximal to the ileal staple line. The larger anvil of the robotic 60-mm stapler is inserted into the colotomy first as the transverse colon tends to be less mobile and more difficult to maneuver. The small bowel is then guided onto the smaller anvil of the stapler and the common channel is created. The common enterotomy may be sutured or stapled closed.

Fig. 1.

Robotic trocar placement for ascending colectomy. A 12-mm trocar is typically placed at arm 4 and stapling is performed from this location. This site may be used for specimen extraction. Adjustments to trocar placement are made to accommodate patient-specific anatomy. ASIS, anterior superior iliac spine. A, assistant port 0. Figure by Andrew Kay.

For a suture closure, our preference is to use a barbed suture such as a V-loc (Covidien, Mansfield, MA). The closure should start from the distal corner as this corner is often more challenging to visualize and approximate. Care must be taken to ensure that any redundancy in the suture is removed. We perform our closure in a single full-thickness layer followed by imbricating the suture line in a running fashion ( Fig. 2D ). Alternatively, the common enterotomy can be resected with the robotic stapler. With this technique, sutures are placed across the common enterotomy and used to elevate it. The stapler can then come underneath and resect the common enterotomy.

Fig. 2.

Robotic ileocolic intracorporeal anastomosis. The colon and small bowel are aligned ( A ). A colotomy and enterotomy are made and the stapler carefully inserted ( B ). The common channel is created ( C ). The common colotomy is closed with a barbed suture starting from the distal corner ( D ).

Colorectal

For left-sided colon resections, a line is drawn from the left midclavicular subcostal region to the anterior superior iliac spine (ASIS). Trocars are placed along this line, one hands breadth apart. We place a 12-mm trocar at arm 3 ( Fig. 3 ). This can also be adjusted to coincide with preoperative ostomy marking if applicable. Arm 4 should be placed at least 3-finger breadths medially from the ASIS to allow for adequate mobility in the pelvis.

Fig. 3.

Robotic left colectomy trocar placement. The trocars are placed in a diagonal line from the left midclavicular line just inferior to the costal margin. ASIS, anterior superior iliac spine. A, assistant port 0. Figure by Andrew Kay.

Once the colon is mobilized and the distal end has been transected, we identify our proximal transection site. We assess the reach of the conduit to the rectal stump. Selective mobilization of the splenic flexure is performed when needed. In many cases, the splenic flexure may be mobilized without repositioning of the robot. Arm 1 (left upper quadrant) is often unable to work in the left upper quadrant and is instead used to provide downward retraction on the colon while arms 2 and 4 are used for mobilization. Integrated table motion may be used to reposition to reverse Trendelenburg if needed. The bedside assistant may also be able to provide adequate retraction for mobilization without redocking. For more difficult splenic flexures, the robot may be undocked and rotated 180 degrees to facilitate mobilization.

An intracorporeal anastomosis may be constructed in several different ways. Our preference is to perform a Baker, or end-to-side, anastomosis. In this method, the proximal transection point is identified and the mesentery divided up to the colon. Indocyanine green is then given intravenously and perfusion assessed. A large, full-thickness colotomy is then made at the site of perfusion change. A second, partial thickness colotomy is made proximally. The 3rd arm of the robot is then undocked and the trocar removed. The incision is enlarged and the fascia spread with a Kelly clamp. The anvil of a 29-mm end-to-end anastomosis (EEA) stapler is then passed into the abdominal cavity. The trocar is replaced and the arm redocked. The anvil is then guided through the large colotomy and the post brought out through the second colotomy. The specimen is then transected with a robotic stapler proximal to the distal colotomy ( Fig. 4 ). A Baker-type end-to-side anastomosis is then created.

Fig. 4.

Robotic intracorporeal colorectal anastomosis. A semicircumferential colotomy is made at the demarcation of perfusion and a second partial thickness colotomy is made proximally ( A ). The anvil is guided into the colon conduit and the post brought out through the proximal colotomy ( B ). The specimen is then divided with a robotic stapler, proximal to the distal colotomy ( C ).

The anastomosis may also be created as an EEA. A purse-string suture technique may be used to secure the EEA anvil in the colon conduit. Alternatively, the anastomosis may be sewn.

Alternatively, both extraction and delivery of the anvil can be done transrectally (or transvaginally). In this technique, the rectum can be opened sharply, or the staple line across the rectal stump excised. The specimen is retrieved and extracted via the rectum, either directly by grasping it with a pair of ring forceps or using a wound protector device through the rectum. This often requires thinning of the specimen. In the pilot study by Minjares-Granillo et al, this was performed for both benign and malignant pathology. ¹⁰ However, this may not be possible for all specimens, as for malignant disease the mesentery and the bowel should be removed as an intact unit to adhere to oncologic principles. The EEA stapler anvil is then delivered via the rectum, and secured in the proximal colon. The rectal stump may be sutured or stapled closed. The anastomosis is then fashioned in the standard fashion. Haas et al have also shown that this technique is feasible for complicated diverticulitis. ¹¹

Conclusion

Robotic intracorporeal anastomosis is a safe and effective technique for both right- and left-sided colon resections. There is increasing evidence that intracorporeal anastomosis results in faster gastrointestinal recovery, decreased hospital length of stay, and decreased postoperative hernia rates.