COLECTOMIA

Indications Colon cancer. Colon polyps not amenable to colonoscopic polypectomy. Diverticular disease. Perforation of the colon for which ostomy is not needed. Inflammatory bowel disease. Volvulus. Stricture. Ischemia. Bleeding. Slow-transit constipation refractory to medical therapy.

Contraindications Widely metastatic colon cancer that is nonoperative or requires a palliative ostomy. Severe peritonitis requiring diverting ostomy, in which primary anastomosis would have an unacceptable leak rate. Hemodynamic instability requiring expeditious ostomy, making primary anastomosis inappropriate.

Informed Consent Expected Benefits Treatment of established colon cancer (or prevention of development). Relief of functional or mechanical colonic obstruction. Treatment (or prevention) of intra-abdominal sepsis secondary to colonic perforation. Treatment of colonic bleeding. Potential Risks Bleeding. Infection. Damage to adjacent structures, including ureter, bowel, spleen, and others. Need for further operations. Anastomotic leak. Need for ostomy. Unresectability. Recurrence of cancer. Cardiopulmonary or other organ failure. Death.

Equipment Bookwalter or similar self-retaining abdominal retractor. Long instruments. Gastrointestinal anastomosis (GIA), linear cutting stapler. Linear thoracoabdominal (TA) stapler. Intraluminal circular end-to-end anastomosis (CEEA) stapler. Laparoscopic equipment if procedure will be performed using laparoscopic techniques, to include: Angled laparoscope. Atraumatic bowel graspers. Laparoscopic GIA staplers. Device for dividing mesenteric vasculature (ie, GIA vascular staple load, LigaSure device, etc).

Patient Preparation Preoperative blood work: Complete blood count to rule out anemia. Type and screen. Carcinoembryonic antigen level. Examination of abdomen for prior incisions. Full colonoscopy to cecum before elective operation, and tattooing of lesions with permanent ink as appropriate. CT scan of abdomen and pelvis with oral and intravenous contrast to evaluate for liver metastasis in patients with cancer. Other diagnostic imaging as appropriate. Mechanical bowel preparation. Deep vein thrombosis prophylaxis with sequential compression devices and consideration of subcutaneous heparin dosing before induction of anesthesia, especially if the patient has been diagnosed with cancer. For patients older than 50 years, -blockade before induction of anesthesia. General anesthesia. Foley catheter. Nasogastric tube. Preoperative antibiotics covering skin and bowel flora (eg, second- or third-generation cephalosporin or penicillin derivative).

Patient Positioning The patient should be supine, with the entire abdomen prepared and draped. Consider lithotomy position if splenic flexure mobilization may be necessary, and for sigmoid colectomy.

Procedure Laparotomy is performed via a midline incision about the umbilicus. The abdomen is explored to palpate the liver for metastasis, visualize peritoneum, examine omentum and lymph nodes, and "run" the bowel. A Bookwalter retractor is placed. Figure 23–1: Vascular anatomy of the colon. The superior mesenteric artery (SMA) supplies the cecum, ascending colon, and proximal transverse colon. The SMA divides into the ileocolic artery (ICA), right colic artery (RCA), and middle colic artery (MCA). Note the hepatic (right) and left branches of the middle colic artery. The inferior mesenteric artery (IMA) supplies the distal transverse colon, splenic flexure, descending colon, sigmoid colon, and upper rectum. The IMA divides into the left colic artery (LCA) and the sigmoid artery (SA), and terminates in the superior hemorrhoidal artery. The marginal artery of Drummond provides collateral circulation along the colon. The inferior mesenteric vein (IMV) meets the splenic vein at the inferior border of the pancreas. Figure 23–2A-D: Extent of resection for colon cancer. Cecal mass: right colectomy is indicated for a mass in the cecum or ascending colon (Figure 23–2A). Transverse colon mass: transverse colectomy or extended right colectomy is indicated for a mass in the transverse colon (Figure 23–2B). Splenic flexure mass: left colectomy is indicated for a mass in the splenic flexure or descending colon (Figure 23–2C). Sigmoid colon mass: sigmoid colectomy is indicated for a sigmoid colon mass (Figure 23–2D). Right Colectomy Indicated for a mass in the cecum or right colon. Resection will include distribution of the ileocolic and right colic arteries, and the hepatic branch of the middle colic artery. Figure 23–3A, B: Lateral peritoneal reflection of the right colon. The right colon is mobilized along the retroperitoneal fold, which forms an avascular attachment of the right colon to the lateral peritoneal wall. A gauze sponge is used to dissect the underlying loose areolar tissue (Figure 23–3A). The duodenum is identified, with care taken to avoid injury. When dissection is carried out in the correct plane, the duodenum should be visualized but not elevated. A soft sponge can be used to keep the duodenum down. Care should be taken to avoid injury to the kidney or Gerota's fascia (Figure 23–3B). Figure 23–4: Transection of the right colon mesentery and named vessels. The right colon is now completely free, except for its mesentery. The right colon is elevated and the mesentery transilluminated to identify avascular tissue for cutting with Bovie electrocautery. As vessels are encountered, they should be clamped as proximally as possible, transected, and ligated. The right colic artery (if present) is ligated at its origin. If the right colic artery is absent and the ileocolic artery arises directly from the superior mesenteric artery, the ileocolic artery is ligated at its origin. The right (hepatic) branch of the middle colic artery is also ligated, sparing the main middle colic artery. Named vessels, including the ileocolic and right colic arteries, and the hepatic branch of the middle colic artery, should be tied twice on the patient's side to reduce bleeding risk. If cancer is suspected, generous mesentery is removed with the goal of achieving a maximal lymphadenectomy. Figure 23–5A-C: Two-load GIA-stapled anastomosis for right colectomy. The right colon is completely free of peritoneal and mesenteric attachments. The planned anastomosis site is now identified by bringing together 5 cm of terminal ileum proximally and the hepatic branch of the middle colic artery distally. Atraumatic bowel clamps are placed 5 cm beyond the planned anastomotic site on each end to prevent spillage. The surgeon should verify that the planned anastomosis will not be under tension when bringing together the antimesenteric border of the two bowel loops. Stay sutures are placed (Figure 23–5A), and hemostats are attached to them. A small enterotomy is made in antimesenteric side of each bowel loop. One fork of the GIA-80 stapler is introduced into each enterotomy (Figure 23–5B). The GIA-80 stapler is fired along the antimesenteric border to anastomose the bowel. Next a second load of the GIA-80 stapler is used to amputate the specimen, including the two enterotomy sites, thereby simultaneously closing the end luminal defects (Figure 23–5C). Alternatives to the two-load GIA-stapled anastomosis include a hand-sewn end-to-end anastomosis (see Figure 23–7), a hand-sewn side-to-side anastomosis, or a four-load GIA-stapled anastomosis. Closure of the resultant mesenteric defect is optional. The abdomen is irrigated with warm saline and closed in standard fashion. Figure 23–1 Figure 23–2A–D Figure 23–3A–B Figure 23–4 Figure 23–5A–C Transverse Colectomy Based on the right colectomy, the transverse colectomy or extended right colectomy for a mass in the transverse colon also includes resection of the right omentum, division of the hepatocolic ligaments, and inclusion of the entire middle colic artery in the resection. Left Hemicolectomy Indicated for a mass in the splenic flexure or descending colon. Resection includes the left colic artery and may be extended to include the sigmoid colectomy discussed later. Begin by incising the white line of Toldt (lateral peritoneal reflection) to mobilize the left colon. This mobilization is extended up to the splenic flexure. Figure 23–6A, B: Mobilization of the splenic flexure. In mobilizing the splenic flexure, the goal is to divide all colonic attachments in a safe manner while preserving the mesentery. Traditionally, the dissection proceeds retrograde. The renocolic ligament is identified and incised (Figure 23–6A). The base of the spleen should now be visible. Next the attachments between the omentum and the spleen, and between the omentum and the colon, are divided. Care should be taken to avoid excessive traction on the colon, which can cause a splenic capsule tear. The splenocolic and pancreaticocolic ligaments are identified and incised (Figure 23–6B). Alternatively, the dissection can proceed anterograde, by elevating the omentum to access the lesser sac. The attending physician may stand between the patient's legs to facilitate this dissection. The splenic flexure is freed. Similar to Figure 23–4, the left colon is elevated and its mesentery transilluminated to identify avascular tissue to be divided with the electrocautery device. As they are encountered, large vessels are clamped and divided at their origin, and ligated twice on the patient side. If cancer is suspected a broad en bloc mesenteric resection is performed to remove as many lymph nodes as possible. Figure 23–7A-E: Hand-sewn, double-layer, end-to-end anastomosis for left colectomy. The left colon specimen has been passed off the field. End-to-end hand-sewn anastomosis begins by placing atraumatic bowel clamps 5 cm past the GIA staple line to prevent spillage of stool. Next, the GIA staple lines are excised. Alignment of bowel: the mesenteric and antimesenteric portions of the remaining bowel should be aligned. Stay sutures are placed at the mesenteric and antimesenteric borders of the planned anastomosis, and hemostats are attached to them. If there is a size mismatch, a small Cheatle slit can be created in the antimesenteric border of the smaller diameter segment (Figure 23–7A). Posterior outer layer Lembert stitches: interrupted 3-0 Lembert sutures are placed in the posterior seromuscular layer to form the posterior outer layer of the anastomosis (Figure 23–7B). Inner layer running stitch: a double-armed 4-0 absorbable monofilament suture is used to create the inner layer of the anastomosis in a running fashion, with full-thickness bites. The submucosa provides the strength (Figure 23–7C, D). Anterior outer layer Lembert stitches: interrupted 3-0 Lembert sutures are placed in the seromuscular layer to form the anterior outer layer, which completes the two-layer anastomosis (Figure 23–7E). The anastomosis is examined to verify that it is widely patent, has an excellent blood supply, shows no evidence of hematoma or leak, and is not under tension. Alternatives to the hand-sewn end-to-end anastomosis include a hand-sewn side-to-side anastomosis (not shown), a two-load GIA stapled side-to-side anastomosis (see Figure 23–5), and an EEA stapled end-to-end anastomosis (not shown). Closure of the resultant mesenteric defect is optional. The abdomen is irrigated with warm saline and closed in standard fashion. Figure 23–6A–B Figure 23–7A–E Sigmoid Colectomy Indicated for a mass in the sigmoid colon or for diverticulitis. Principles are similar to those for left colectomy. Figure 23–8: Mobilization of the sigmoid colon. Particular attention must be paid to avoid damaging the left ureter, which is extremely close to the sigmoid colon as it passes over the left iliac artery. Consider preoperative placement of a ureteral stent, especially if significant inflammation or scar tissue is anticipated in the area. It may not be necessary to always mobilize the splenic flexure; however, a tension-free anastomosis must be achieved. The anastomosis may be hand sewn end to end, hand sewn side to side, stapled side to side using a GIA stapler, or stapled end to end using an EEA stapler. Figure 23–8 Laparoscopic Colectomy The patient is placed in deep Trendelenburg position, and the right side of the table is then rotated up. Consideration should be given to preoperative placement of an infrared ureteral stent, which can be seen using a special laparoscope. We prefer to approach the colon medially, thereby letting the lateral peritoneal fold provide initial retraction. Figure 23–9A-D: Laparoscopic assisted right colectomy. Port sites: 5-mm ports are placed in the midline at the epigastric and suprapubic positions, and a 12-mm port and 5-mm port are offset to the left side of the umbilicus, maintaining a hand's breadth of space between each port (Figure 23–9A). Avascular mesenteric windows are created with cautery. An endovascular stapler is then used to staple vessels, beginning with the ileocolic artery, and repeating for the right colic artery (Figure 23–9B). The lateral peritoneal reflection is divided (Figure 23–9C). Next, a 5-cm long incision is made on the right side of the abdomen. The rectus is swept medially for a rectus-sparing incision through the posterior rectus sheath. The right colon is then externalized (Figure 23–9D). A two-load GIA-stapled simultaneous colon resection and extracorporeal anastomosis is performed, as previously described (see Figure 23–5). Figure 23–9A–D

Postoperative Care Diet is advanced as tolerated after confirming flatus. A Foley catheter is inserted to monitor adequacy of urine output for the first 24 hours. -Blockade is continued if appropriate. Deep vein thrombosis prophylaxis should be continued. Patients are encouraged to be ambulatory and should be out of bed three times daily on postoperative day 1.

Potential Complications Intraoperative and Technical Injury to the ureter. Injury to the duodenum. Injury to other bowel. Small deserosalizations can be repaired with Lembert stitches. Care should be taken to avoid grasping the bowel during the operation. Epiploic appendages should be grasped instead. Injury to the spleen. A topical hemostatic agent can be applied or splenorrhaphy or splenectomy performed. Inadequate blood supply at the anastomosis. Additional bowel should be resected. Consider using Doppler ultrasound to evaluate blood flow to the anastomosis if concerned. Anastomosis under tension. Additional bowel can be mobilized. Stool spillage and tumor cell spillage, creating the potential for abscess or "drop metastases." Noncrushing bowel clamps should be used proximal and distal to the line of colonic division. Early Postoperative Period Wound infection. Staples should be removed as needed, followed by confirmation that fascia are intact. The wound should then be packed and allowed to heal by secondary intention. Anastomotic leak. In some patients, tachycardia may be the only sign; others may have prolonged ileus or appear septic. Intra-abdominal abscess. Typically diagnosed by CT scan on postoperative days 5–7. Can often be treated using a percutaneous drain placed by the radiology service. May be secondary to an anastomotic leak. Colocutaneous fistula. Late Postoperative Period Anastomotic stricture. Anastomotic recurrence of cancer. Incisional hernia. Internal hernia. Ureteral stricture from ureteral devascularization.

Pearls and Tips Take no chances with the anastomosis. Ensure that the anastomosis is widely patent, has an excellent blood supply, shows no evidence of hematoma or leak, and is not under tension. Assess visually, tactilely, and via Doppler ultrasound if necessary. Do not leave the operating room if the viability of the anastomosis is questionable. When mobilizing the splenic flexure, always avoid excessive traction on the colon to prevent tearing of the splenic capsule. Suspect intra-abdominal abscess in patients with postoperative fever, tachycardia, or prolonged ileus. Diagnose with CT scan.

References Ballantyne GH. Atlas of Laparoscopic Surgery. Philadelphia, PA: WB Saunders; 2000. Cameron JL. Current Surgical Therapy. Philadelphia, PA: Elsevier Mosby; 2004:211–216. Scott-Conner CE. Chassin's Operative Strategy in General Surgery. New York, NY: Springer; 2002:359–418. Zollinger RM Jr, Zollinger RM Sr. Zollinger's Atlas of Surgical Operations. New York, NY: McGraw-Hill; 2003:112–139.