Townsend Courtney M.Jr., Evers B. Mark. Atlas of General Surgical Techniques: Expert Consult

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CHAPTER 60 • Left and Sigmoid Colectomy 677

2. DISSECTION

◆ An intra-abdominal exploration is performed to determine the extent of disease and resect-

ability. The small bowel is packed and tucked away to the right upper quadrant of the ab-

dominal cavity. The left colon is mobilized from its retroperitoneal attachments by incising

the white line of Toldt (Figure 60-2).

Lateral peritoneal

attachment

White line of Toldt

FIGURE 60 –2

678 Section IX • Colon

◆ The sigmoid and descending colon is retracted medially, exposing the left ureter and gonadal

vessel (Figure 60-3).

◆ Continuing cephalad along this retroperitoneal plane, divide the renocolic and splenocolic

ligament to release the splenic ﬂ exure (Figures 60-4 and 60-5).

Ureter

Gonadal vessels

FIGURE 60 –3

CHAPTER 60 • Left and Sigmoid Colectomy 679

Splenocolic ligament

FIGURE 60 –5

Spleen

Kidney

Omentum

Splenocolic ligament

FIGURE 60 –4

680 Section IX • Colon

◆ Dissecting from the left aspect of the omentum, mobilize the gastrocolic ligament off the

transverse colon and splenic ﬂ exure (Figure 60-6).

◆ The least traumatic way of taking down the splenic ﬂ exure involves dividing these avascular

ligaments from either side of the splenic ﬂ exure (see Figure 60-5) rather than pulling on the

ﬂ exure with downward traction.

Gastrocolic ligament

incised

FIGURE 60 –6

CHAPTER 60 • Left and Sigmoid Colectomy 681

◆ The blood supply to the left colon originates from the inferior mesenteric artery and mainly

involves the left colic artery. The points of transection of the proximal and distal large bowel

are decided upon based on the mesenteric blood supply. The colon is then divided with

the gastrointestinal anastomosis (GIA) stapler at the proximal and distal resection margins

(Figure 60-7). The left colic artery and proximal sigmoid arteries are ligated at their ori-

gins. Careful attention must be paid to the bowel ends to ensure a healthy blood supply

and that the ends would reapproximate without tension.

Bowel divided

with GIA stapler

FIGURE 60 –7

682 Section IX • Colon

◆ The anastomosis joining the distal transverse and distal sigmoid colon can be hand-sewn

(Figures 60-8 through 60-11) or stapled, as described previously. When performing an

anastomosis using an end of bowel, such as an end-to-end anastomosis, at least a 1-cm

edge of bowel must be cleared of fat, mesentery, and appendices epiploicae, exposing the

serosa.

Posterior layer of interrupted

seromuscular stitches (Lembert)

FIGURE 60 –8

FIGURE 60 –9

CHAPTER 60 • Left and Sigmoid Colectomy 683

Connell sutures

anterior anastomosis

FIGURE 60 –10

FIGURE 60 –11

Lembert sutures

684 Section IX • Colon

◆ The sigmoid colon may be resected if the tumor is located in the distal descending colon

or sigmoid colon. As the retroperitoneum is exposed, the left ureter should be identiﬁ ed,

typically anterior to the external iliac vessels. The limits of resection are determined: proxi-

mal sigmoid tumors will involve sacriﬁ ce of branches of the left colic artery, and distal sig-

moid tumors will involve sacriﬁ ce of branches of the superior rectal artery and transecting

the colon to the level of the sacral promontory. The splenic ﬂ exure may have to be mobi-

lized to create a tension-free anastomosis.

◆ Hand-sewn end-to-end (see Figures 60-8 through 60-11) anastomosis: After noncrushing

bowel clamps are applied proximal to the bowel ends, the staple lines are cut using electro-

cautery or Metzenbaum scissors. In a standard two-layer anastomosis, the posterior (outer)

layer of the transverse colon and proximal rectum are reapproximated with 3-0 silk inter-

rupted (Lembert) sutures. Two continuous absorbable sutures are used in the posterior

inner row (see Figure 60-9), and each is brought anteriorly, where the transition to Connell

sutures is made (see Figure 60-10).

◆ Finally, the anterior (outer) layer is completed with interrupted Lembert sutures (see

Figure 60-11). The mesenteric defect can be reapproximated with a continuous absorb-

able stitch, with care to ensure that the underlying vessels supplying the bowel are not

compromised.

3. CLOSING

◆ The abdominal cavity is irrigated with copious warm saline. The omentum can be overlaid

on top of the newly formed anastomosis. After ensuring hemostasis, sponge counts, and

instrument counts, close the abdomen using a no. 1 polydioxanone (PDS) suture. The sub-

cutaneous tissue is irrigated again, and the skin is closed with skin clips.

STEP 4: POSTOPERATIVE CARE

◆ Ambulation and incentive spirometry on postoperative day 1 is important for the preven-

tion of postoperative atelectasis. Oral intake of clear liquids can begin after removal of the

nasogastric tube. The Foley catheter is left in place for a few days because of the high inci-

dence of urinary retention in male patients.

STEP 5: PEARLS AND PITFALLS

◆ Injury to the spleen: Omental adhesions between the omentum and splenic capsule can

cause inadvertent avulsion or injury to the splenic capsule if traction on the omentum is

applied.

◆ Injury to the left ureter: After division of the renocolic ligament, the left ureter is visualized

in the left retroperitoneum. The entire length of the ureter can be traced down to the pelvis

if necessary.

CHAPTER 60 • Left and Sigmoid Colectomy 685

SELECTED REFERENCES

1. Wille-Jørgensen P, Rasmussen MS, Andersen BR, Borly L: Heparins and mechanical methods for thrombo-

prophylaxis in colorectal surgery. Cochrane Database Syst Rev 2004(4):CD001217.

2. Stahl TJ, Gregorcyk SG, Hyman NH, et al: Practice parameters for the prevention of venous thrombosis.

Dis Colon Rectum 2006;49:1477-1483.

686

STEP 1: SURGICAL ANATOMY

◆ The descending colon is covered by peritoneum on the anterior and lateral surfaces and

attaches to the retroperitoneum on the posterior side.

◆ Structures beneath the descending colon include the left kidney, the proximal ureter, and

the inferior mesenteric vein.

◆ The splenic ﬂ exure is much higher than the hepatic ﬂ exure, a consideration to be noted when

placing ports for laparoscopic dissection. Mobilization of the ﬂ exure requires division of the

lienocolic ligament, a maneuver that must be carefully done to prevent splenic capsular tear.

◆ The main blood supply to the left colon includes the left colic artery and the superior

sigmoid arteries. Collateral ﬂ ow may be provided by the marginal arteries and the arc of

Riolan, a meandering artery from the middle colic artery to the inferior mesenteric artery.

◆ The sigmoid colon is highly mobile, typically with a long mesentery and variable length. It

is completely covered by peritoneum and is attached to the abdominal wall by the lateral

peritoneal attachment called the “white line of Toldt,” which extends upward to include

attachment of the left colon, as well. Preservation of this attachment allows for countertrac-

tion during laparoscopic mobilization.

◆ The blood supply of the sigmoid colon includes the inferior mesenteric artery and its sig-

moidal branches.

◆ The intersigmoid fossa is a recess at the base of the mesosigmoid that provides an anatomic

landmark for locating the left ureter, which courses beneath the fossa and parallel just

medial to the gonadal vein.

◆ The superior hypogastric plexus provides sympathetic innervation for erectile function and is

situated at the bifurcation of the aorta in close proximity to the inferior mesenteric artery (IMA)

CHAPTER

Left and Sigmoid Colectomy

(Laparoscopic-Assisted)

Valerie P. Bauer