Trocar positions , numbers indicate trocar sizes in mm
In laparoscopic right colectomy with extracorporeal anastomosis (ECA) , the camera trocar is removed, and a periumbilical incision is made around the left side of the umbilicus to create a mini-laparotomy. A 4- or 5-cm incision is typically adequate. A wound protector is placed, and the mobilized right colon is exteriorized. Alternative extraction sites would be the right lower abdominal trocar site (transverse incision) or a Pfannenstiel incision which may bear a lower risk of hernias, but both alternatives would demand a more comprehensive mobilization of the transverse colon for optimal reach to create a tension-free anastomosis.
Alternatively, laparoscopic right colectomy can be combined with intracorporeal anastomosis (ICA), which facilitates specimen extraction through a Pfannenstiel incision, since extensive mobilization of the transverse colon and terminal ileum is not needed. For detailed techniques of ECA and ICA during laparoscopic and robotic right colectomy, please refer to the chapters on options for ileocolonic reconstruction (Chap. 14) and robotic right-sided colon resection (Chap. 15), respectively.
The position of the tumor is verified by careful palpation. Mesenteric transection is completed toward the ileum and transverse colon at the sites of planned transection. The bowel is divided using a linear stapler. Photo documentation of the specimen may be performed with a ruler next to it. The central transection areas of the major vessels may be marked using sutures of different colors based on institutional availability. The ileocolic anastomosis is performed with proper orientation of the ileum and colon. The oncologic principles of conventional surgery do not change as the omentum is taken off the right transverse colon in cancers proximally to the hepatic flexure and taken along en bloc with the specimen in tumors of the hepatic flexure and right transverse colon.
Operative Technique: Comparison with Lateral-to-Medial Approach
The technique of creating a retroperitoneal tunnel in the medial-to-lateral approach offers several advantages such as a minimized risk of injury to the retroperitoneal envelope which covers the right ureter and the gonadal vessels. Furthermore, the named arteries are clearly visible posteriorly at their origins, and they may be ligated early, proximally, and safely to minimize the risk of bleeding and keeping the small intestine out of the operative field; an early proximal ligation of the mesenteric vessels (observation of no-touch isolation technique) is achieved. By leaving the lateral attachments of the colon intact until the mesenteric division has been carried out, important natural anatomic countertraction is applied to the bowel as the mesentery and bowel are mobilized. Colectomy is facilitated by leaving the lateral attachments intact, and the described anatomic landmarks are highlighted clearly. Only minimal manipulation of the tumor-bearing colon is needed, as most of the colon mobilization and dissection of the mesentery are accomplished before the cecum and ascending colon are freed from their lateral attachments (no-touch isolation technique).
In a lateral-to-medial approach, the tumor-bearing colon is mobilized first. The lateral dissection is started by elevating the colon on its vascular pedicle, and then both planes of Gerota’s fascia must be entered laterally and dissected apart from each other. The mesenteric and vascular division is the same as in a medial-to-lateral approach with respect to the principles of CME. The vessels are ligated intra- or extracorporeally in a second step; however, it must be ensured that the superior mesenteric vessels and the origins of the mesenteric vessels are clearly identified and divided at their origins. An assistant has to pull on the tumor-bearing bowel to create traction and countertraction for central exposure of the mesentery and avoid the risk of tearing the colon and mesentery. It is important to note that the mobilized colon and small bowel become more difficult to manage laparoscopic surgery relative to open surgery.
Pitfalls and Troubleshooting
For carcinomas of the hepatic flexure and right transverse colon, an extended right hemicolectomy is indicated. The omentum is not dissected off the colon, but the dissection is continued along the lower edge of the duodenum toward the right aspect of the greater curvature of the stomach. The gastrocolic ligament is transected at the left transverse colon. The middle colic vein and artery are dissected and transected centrally at the level of the SMV and SMA to assure a complete lymphovascular resection. The right branches of the middle colic vessels are also divided. In patients where a tension-free anastomosis may be challenging, such as those who are obese, splenic flexure mobilization in combination with further takedown of the omentum may be beneficial as well as a total laparoscopic approach with intraabdominal bowel transection and creation of an intracorporeal ileocolonic anastomosis (ICA) to avoid tension from an extracorporeal approach (ECA).
In obese patients, the landmarks of dissection are more difficult to find, especially the SMV. In such cases, a laparoscopic lateral-to-medial approach may provide improved exposure. In particularly challenging cases, the laparoscopic colon mobilization may be followed by central mesocolic and lymph node dissection in an open technique through a relatively short midline incision.
If the tumor has not been tattooed and cannot be identified at exploration, intraoperative colonoscopy may be necessary. CO2 insufflation should be used to minimize dilatation of the colon that will hinder further laparoscopic dissection. If the tumor cannot be localized laparoscopically or endoscopically, conversion to laparotomy and careful palpation of the colon may be necessary. As pointed out previously, a conversion to a hand-assisted approach can facilitate medial-to-lateral mobilization, especially in reoperative and obese cases.
The most frequently described intraoperative complication is bleeding. In order to avoid any vascular injury which may be hazardous especially with SMV, SMA, and middle colic vessels, a very slow and meticulous dissection technique is imperative. The laparoscopic energy devices and instruments used for dissection should be carefully observed to avoid contact with vessels. Especially in obese patients, the visualization may be difficult, and the threshold for conversion should be kept very low. As explained above, in a medial-to-lateral approach, the risk of injury to adjacent organs is low: duodenal adhesions by small ligaments toward the posterior mesocolon should be taken down cautiously. The same applies to adhesions between the pancreatic head and the mesocolon. In cases of previous pancreatitis with firm adhesions, conversion is recommended. The ureter normally stays safely below the surface of the retroperitoneal envelope; whenever possible it should be visualized.
If against expectations from preoperative staging by CT scans a T4 tumor is found at exploration, conversion to open approach for planned en bloc resection is recommended.
There are no data of the learning curve in oncologic laparoscopic right hemicolectomy. However, when possible, the technique of CME should be mastered first in the context of open surgery to better understand variations in the relevant anatomy. Also, the laparoscopic expertise required to perform these cases should be advanced, and it may be helpful to practice the procedure first in benign cases, especially adenomas. The retroperitoneal tunnel approach has advantages also when applied in Crohn’s disease and may be practiced in such cases first to gain confidence and become familiar with the technique.