Program Colorectal Pathway: Laparoscopic Splenic Flexure Release (Tips and Tricks)

Perioperative Planning, Patient Workup, and Optimization

Patients undergoing SFR as part left-sided resection will undergo standard workup, staging, and preoperative planning based on the actual diagnosis. Almost invariably, patients will undergo computed tomography scanning (CT) as part of their workup. Additionally, a barium or gastrografin enema can be very helpful in demonstrating the configuration of the descending colon, the level and extent of diverticular disease, and may help with the decision-making related to extent of the resection that may be needed. However, it is rarely the case that any imaging is obtained for the sole reason of assessing the suitability of the splenic flexure for mobilization.

There is a lack of standardization of preoperative assessment of the blood supply of the splenic flexure , which has proven to have significant variability. Different recognizable patterns have been identified in a recent radiologic study, in which preoperative blood supply was determined by using CT angiography and CT colonography with 3-D reconstructions. In this publication, 39.7% of the blood supply was identified to originate from the left colic artery (LCA), 17.8% from the left branch of the middle colic artery, 9.9% from the LCA and the left branch of the middle colic artery, 4.2% from the accessory left colic artery, 2.6% from the LCA and the accessory left colic artery, and 25.8% from the marginal artery [12]. These newly classified patterns differ from the traditional belief that 85–89% of the blood supply of the splenic flexure originates from the left colic artery and 11–15% from the left branch of the middle colic artery [13]. That being said, we know that the descending colon and splenic flexure are well supplied by vascular arcades originating from the middle colic vessels that connect with blood supply that comes from the inferior mesenteric artery (Fig. 4.3), and it is extremely rare that ligation of the IMA proximal to the left colic results in frank ischemia in the left colon when the proximal mesentery is uninjured.

../images/465809_1_En_4_Chapter/465809_1_En_4_Fig3_HTML.jpg — Fig. 4.3

Vascular arcades connecting the middle colic vessels to the blood supply of the IMA

Technology to assess the blood supply of the large bowel preoperatively is available [14]. There is no evidence, however, to indicate that patients have a decrease in the rate of complications secondary to ischemia when they undergo preoperative assessment of the blood supply compared with those patients who do not, and this does not play a role in routine preoperative planning for patients [15]. Please refer to Chap. 29 on best practices to assess the integrity and perfusion of left-sided anastomoses.

Operative Setup

The operative setup would be the same as for left-sided and pelvic procedures and/or total abdominal colectomy. The optimal trocar position includes a 10–12 mm camera port through or near the umbilicus, a second 10–12 mm port in the right lower quadrant (main port for the left-sided dissection), a 5 mm port in the lower aspect of the right upper quadrant, close to the umbilicus, and a second 5 mm port on the contralateral side. The assistant should ideally stand either between the legs or on the right side of the patient with the primary surgeon standing on the right side during the SFR. The surgical table could either be on mild or full reverse Trendelenburg position. This is optional and depends on the surgeon’s preference. In our practice, the patient remains in Trendelenburg position throughout the SFR.

Operative Technique: Surgical Steps

The operative approaches for release of the splenic flexure are well established and should be performed in a standardized fashion. There are three options available to the surgeon including the supramesocolic, the inframesocolic, and the lateral to medial approach.

Supramesocolic Approach

The patient is placed in a reverse Trendelenburg roughly five degrees, maximal right side down. The camera is trans- or supraumbilical; the left hand is used to grasp the gastrocolic ligament close to the stomach. Gravity allows for downward traction of the transverse colon, putting the gastrocolic ligament on stretch (Fig. 4.4). The right hand coming from the right lower quadrant is utilized to identify first and then incise the perforating veins between the gastroepiploic veins on the greater curvature and the transverse colon (Fig. 4.5). Once this space is entered, the lesser sac is immediately visualized and incised in a central to lateral fashion from roughly the mid-transverse colon out to the splenic flexure through the gastrocolic ligament. The surgeon must be careful while performing this aspect of the operation to avoid going too deep and inadvertently injuring the mesentery of the transverse colon. This is a critical point as injury to the mesentery of the transverse colon will put at risk the blood supply to the descending colon, which is necessary for the anastomosis. The dissection should be carried out laterally as far as can easily be accomplished. The dissection should then be carried out toward the upper 10 cm of the line of Toldt along the proximal descending colon. The attachments of the retroperitoneum and the mesentery of the descending colon should be identified and pushed apart along an avascular plane. This can be developed bluntly and does not require any sharp dissection (Fig. 4.6). By paying strict attention here, the surgeon can notice the difference in color and texture of the fat of the colonic mesentery, deep to Gerota’s fascia and retroperitoneal fat (Fig. 4.7). Once this is mobilized, the hands are switched so that the traction of the transverse colon is brought down to the left hip by the right hand, and the energy source is coming from the left hand, bringing the thermal spread and/or scissors away from the transverse colon and a wayward diverticulum. The attachments of the greater omentum to the spleen must be carefully divided. Care must be taken not to put undue traction on the colon or the greater omentum. The greater omentum may be attached to the splenic capsule as this will potentially be an area where capsular tearing of the spleen can occur. It is always a good idea at this point of the operation to gently pull medially on the greater omentum while watching the spleen for movement, to gauge the adherence and possible danger of this manipulation. For lower anastomoses, where a coloanal or low rectal anastomosis is necessary, the mesentery must be released from the inferior border of the pancreas. By identifying the mesentery and incising it approximately 1 cm distal to the inferior border of the pancreas, the transverse colonic mesentery can be liberated from its attachment to the retroperitoneum and along Gerota’s fascia. If all these steps are completed as described above, splenic flexure release will be complete (Figs. 4.8a, b and 4.9).