Laparoscopic Left Colectomy (Left Hemicolectomy) Technique

Ngu et al reported that robotic surgery, as compared with conventional laparoscopic surgery, leads to superior visualization and more dynamic assistance in hemicolectomies. ^[16] This conclusion was based on the operative video assessment of 40 procedures that were stratified according the method of surgery, the type of hemicolectomy, and the seniority of the assistant.

The patient is positioned as previously described (see Patient Preparation). Whether a lateral-to-medial (LTM) or a medial-to-lateral (MTL) approach is used is a matter of preference. The most important feature of colon mobilization is identification of the interface between the colonic mesentery and the retroperitoneum. This tissue interface is not the white line of Toldt, though the Toldt line must be incised to expose the mesocolon-retroperitoneum interface.

The author prefers an MTL approach (see the video below), for several reasons. This approach brings the inferior mesenteric artery (IMA) immediately into view, as well as two avascular mesenteric windows, which are always present immediately cephalad and caudal to the IMA. In addition, it requires only one retracting instrument, which facilitates single-site surgery, and it does not require looking "over" the colon from the patient’s right side, thereby allowing less vigorous retraction of the colon and creating less of an opportunity for injury to the specimen.

The mesentery can be easily scored along its medial aspect either mechanically or with a cautery, and the sigmoid mesentery can be retracted away from the retroperitoneum while an energy device is used to perform a blunt and bloodless tissue distraction that involves elevating the mesentery en bloc away from the retroperitoneum.

This technique can also minimize the extent to which tissue is grasped and exposed to electrical energy, until such time as the left ureter is exposed. The retracting instrument can be inserted into the plane between the mesentery and the retroperitoneum, lifting the mesentery toward the anterior abdominal wall without grasping and tearing tissue.

The IMA is circumferentially isolated to ensure that the left ureter is not inadvertently transected or thermally injured. The left ureter and IMA are, in the native anatomy, immediately adjacent, with the vessel lying over the ureter. For this reason, as well as both to allow a complete mobilization of the sigmoid colon and to achieve an adequate lymph node yield in cases of cancer, the sigmoid colon is completely mobilized to the midline of the peritoneal cavity.

With the IMA skeletonized and with the colon mobilized so that the colon can be retracted straight toward the anterior abdominal wall, the left ureter can easily be located from both a medial and a lateral view. These points should be documented in the operative report, describing the care taken to identify and protect the left ureter. If these steps cannot be achieved, the IMA should not be blindly ligated, and the procedure should be preemptively converted to laparotomy for the patient’s safety.

For colonic malignancies, the IMA should be ligated proximal to its bifurcation to remove the entire lymph node cache by transecting the artery near its junction with the aorta. Conversely, for benign diseases, the IMA may be ligated more distally so as to reduce the risk of urinary and sexual dysfunction from damage to the autonomic nerves in the para-aortic region.

Even in the setting of benign disease, by ligating the IMA at the level of its bifurcation and using a more proximal level of mesenteric transection, fewer second- and third-order arterial vessels are encountered, which reduces the risk of pesky bleeding because a more proximal mesocolic dissection involves bloodless planes between named vessels.

This technique also removes diseased and thickened mesentery that must be maneuvered over or around in constructing a tension-free colorectal anastomosis. Furthermore, mobilizing the colon in this manner, where the mesentery is freed from the retroperitoneum at the midline peritoneal cavity, allows full exposure and isolation of the left ureter and kidney, prevents devascularization of the colon through distal transection of its mesentery, and provides maximal colonic length for a proper anastomosis.

The descending colon can be easily mobilized as far proximally as the splenic flexure by continuing the same method of mobilization as discussed for the sigmoid colon. (See the video below.)

The descending colon is retracted toward the anterior abdominal wall and the midline of the peritoneal cavity. The line of fusion between the posterior aspect of the colon mesentery and the retroperitoneum marks the line of dissection, allowing mobilization of the remaining left colon to the midline. The colon is retracted, and the line of fusion either is scored with electrical energy or is mechanically separated through tissue distraction. With proper retraction, this is a quick, bloodless process that does not require electrical energy to perform safely.

Although mobilization of the splenic flexure (see the videos below) is not always necessary, it is sometimes mandated for a tension-free anastomosis. This is a more complex maneuver because of the close proximity of the stomach, spleen, and pancreas, as well as the need to avoid inadvertently transecting the transverse mesocolon, which potentially devascularizes the large intestine to be used for the anastomosis.

Splenic flexure mobilization may not be rigorously defined, and the term may be used in various ways by different surgeons. As a rule, however, the term splenic flexure mobilization should not be used to refer to incising the line of Toldt to the level of the splenic flexure but should be reserved for some degree of transection of the distal transverse mesocolon for the purpose of relocating the splenic flexure away from the spleen.

The MTL approach preferred by the author involves placing the patient in maximal reverse Trendelenburg positioning with continued right lateral decubitus tilt. The midpoint of the gastrocolic ligament is transected, allowing entry into the lesser sac. The remaining gastrocolic ligament is transected to the level of the inferior pole of the spleen, and this point of view allows the surgeon to avoid getting lost and ending up near the splenic hilum—an easy mistake to make in a patient with more visceral obesity.

The stomach is then reflected cephalad so as to expose the posterior gastric wall, which can be easily and inadvertently injured during splenic flexure mobilization. This also exposes the pancreas, which is important in that the level of mesenteric transection is several centimeters caudal to the inferior border of the pancreas. This is to preserve collateral arterial blood flow, as well as to maximize colonic length.

By this time, avascular mesenteric windows on either side of the left branch of the middle colic vessel have been further developed and exposed through the previous descending colon mobilization. These windows can then be easily identified and opened, allowing proximal transection of the left branch of the middle colic artery near the inferior border of the pancreas.

The splenic flexure proper can then be transected in an MTL direction, with the inferior pole of the spleen, the pancreas, and the transverse mesocolon clearly delineated. With the patient in reverse Trendelenburg, the colon naturally moves away from the spleen, allowing further exposure of the spleen without retraction. The previous transection of the gastrocolic and splenocolic ligaments prior to the mesenteric resection allows the colon to be safely retracted caudally without tearing of the splenic capsule; the spleen and colon are no longer attached.

The transverse colon can be mobilized to the midline of the peritoneal cavity, and the main branch of the middle colic artery and the marginal artery are preserved, with the latter now serving as the main tributary to nourish the descending colon. This places the distal half of the transverse colon and the descending colon in the midline of the peritoneal cavity, in a straight line toward the pelvis, and provides adequate length for virtually every colorectal anastomosis.

Splenic flexure mobilization is arguably the most dangerous maneuver that colorectal surgeons perform. With a proximal transection of the transverse mesocolon, a bleeding vessel can potentially retract into a retropancreatic position, continuing to bleed but not visible without pancreatic mobilization.

Application of an endostapler to the proximal and distal resection margins, followed by specimen exteriorization and creation of an anastomosis, is self-explanatory (see the videos below).

Every effort should be made to transect as much mesentery as possible toward the bowel wall before stapler application in an effort to prevent bleeding after stapling. The endostaplers must be placed straight across the bowel, not at an angle; angled placement creates zones of ischemia, as well as a higher risk of inadequate margins of resection for cancers. If postcolectomy bleeding occurs, it may be treatable by means of endoscopy. ^[29]

A study assessing the effect of the site used for speciment extraction on the incidence of wound infection after laparoscopic colon resection found that infection rates were higher when midline or Pfannenstiel incisions were used for specimen extraction and lower when right-lower-quadrant or left-lower-quadrant incisions were used. ^[30]

With regard to the typical course of patients undergoing a laparoscopic left colectomy, their bladder catheter is removed within 24 hours after the procedure, and a solid food diet is started immediately after surgery. The patient is provided with low-dose patient-controlled analgesia, and every effort is made to use nonsteroidal anti-inflammatory drugs (NSAIDs) and other nonopioid medications to control surgical-site discomfort.

The patient may be safely discharged home once the passage of flatus resumes, which is usually on postoperative day 2 or 3. Given that most patients undergo mechanical bowel preparation, awaiting a bowel movement would seem to introduce an unnecessary delay in hospital discharge.

A study by Pardo Aranda et al suggested that fast-track recovery protocols could be applied to single-port laparoscopic surgical procedures on the colon as safely and effectively as they could to multiport laparoscopic surgical procedures. ^[31]

A prospective study of patients undergoing elective colorectal resections found that those treated with a standardized enhanced recovery program (ERP; n = 100), as compared with those treated before the introduction of the ERP (n = 100), had significantly shorter hospital stays, imposed lower nursing worloads, and showed no increase in postoperative complications, 30-day readmission, or mortality. ^[32] In addition, total mean direct costs per patient were significantly higher for patients in whom the ERP was not implemented.

A study (N = 23) by Zarzavadjian le Bian et al addressed the safety and feasibility of repeat laparoscopic colorectal resection (LCRR; right side, n = 11; left side, n = 8; proctectomy, n = 4) in patients with colorectal cancer (CRC) or benign conditions. ^[33] Indications for repeat LCRR included CRC, dysplasia, anastomotic stricture, and inflammatory bowel disease (IBD). Thirteen (57%) patients required conversion to laparotomy (12 for intense adhesions). Conversion rate, operating time, and intraoperative blood loss were greater for repeat LCRR than for primary LCRR; however, oncologic outcomes were not compromised with repeat LCRR, which was found to be a safe and feasible procedure for CRC.