Tumor in the descending colonMedical editor Arild Nesbakken MD
Professor of Surgery
Oslo University Hospital
For cancer in the descending colon, a left-sided hemicolectomy and a standard bowel- and lymph node resection are performed. The bowel is divided to the left on the transverse colon and upwards on the rectum. The distal sigmoid colon is not being retained because the blood supply may not remain satisfactory.
The inferior mesenteric veins are divided centrally. (The artery at the aorta and the vein close to the edge of the pancreas.)
- Laparotomy- or laparascopic equipment
Bowel emptying is not necessary.
- intravenously antibiotic prophylaxis at the latest at the beginning of the anesthesia. It should be considered whether the patients in addition should have oral antibiotics from the day before the surgery.
- thrombosis prophylaxis with low molecular weight heparin.
During the surgery it is inserted:
- epidural catheter for pain management.
- urinary catheter.
- naso-gastric tube which is removed by the end of the surgery.
The procedure is performed in the same way as sigmoid resection. The difference is that the oral bowel end here is divided at the left on the transverse colon
Laparoscopic sigmoid resection.
Step 1 – Trochar insertion and diagnostic laparoscopy
- Trocharinsertion with visiport just to the right of umbilicus, 5 mm epigastric port, and 12 mm port in the right fossa and 5 mm in the left fossa and suprapubically. Avoid the inferior epigastric vessels and insertion of the trochar too low on the abdomen which may impede the angulation within the abdominal cavity.
- Examine the primary tumor for perforation and/or infiltration into adjacent organs. Thereafter the liver and the total abdominal cavity is inspected with regard to metastases, peritoneal carsinomatosis (especially the pelvis and the paracolic gutters) and other pathology.
Step2 – Release the mesentery and colon (left transversal, left flexure and descending colon) in the mesocolic plane
- The patient in Trendelenburg’s position tilted towards the right. Position the omentum over the liver and put the small bowel package over the midline to the right. If necessary apply an extra trochar suprapubically to expose the ligament of Treitz.
- Open the peritoneum on the posterior abdominal wall medially to the origin of the inferior mesenteric artery after possible adherances are released at the ligament of Treitz.
- Continue in the mesocolic plane towards the left flexure and divide the inferior mesenteric vein. Dissect in the mesocolic plane cranially (avoid dissection dorsally to the pancreas) and continue anteriorly to the pancreas and into the lesser sac. Be aware that arcade vessels can be located relatively centrally along the colon.
- Divide adherances along the tail of the pancreas all the way to the lateral abdominal wall. Continue under the left flexure and descending colon (in front of the pancreas and the left kidney).
- Continue in front of the colon where the gastro-colic ligament is divided just caudally to the gastro-epiploic vessels, divide the splenocolic ligament.
- Divide the peritoneum laterally the descending colon along “the white line of Tod”. Carry through till the anterior and dorsal dissection have met and the left flexure and descending colon are completely free.
Step 3 – Central resection of the inferior mesenteric artery
- Lift sigmoid and its mesentery anteriorly and to the left and put it on tension. Incise the peritoneum at the pelvic entrance till the origin of the inferior mesenteric artery in line between the posterior abdominal wall and the sigmoid mesentery.
- Continue in the dorsal mesocolic plane behind the sigmoid mesentery towards the lateral abd ominal wall (avoid left ureter).
- Dissect the origin of the inferior mesenteric artery at the aorta and divide with hemlock. During this dissection the main sympathetic nerves must be visualized and retracted posteriorly to avoid injury. Avoid dissection into the parietal fascia in front of the aorta and posterior abdominal wall. (If the proper vessel wall is visualised the dissection has been carried on too deeply and the nerve plexus may have been injured).
Step 4 – Finish the dissection of the sigmoid
- Grip the divided mesenteric inferior artery and lift it forward.
- Continue the dissection in the mesocolic plane till the lateral abdominal wall behind the all descending colon to the upper rectum. Carefully sweep the nerves dorsally.
- Finish the peritoneal incision medially and dorsally till the point of the division of the rectum.
- From the anterior free the sigmoid until the whole left colon, sigmoid and upper rectum is completely free.
Step 5 – Divide the bowel on the oral rectum
- Divide the mesorectum and the superior rectal vessels and prepare the bowel tube.
- Divide with stapler instrument. The distal sigmoid must be completely resected to ensure adequate circulation in the anal bowel tube
Step 6 – Exteriorize the specimen and oral bowel end
- Make a 6 cm incision transversally above the symphysis (Pfannenstihl incision).
- Incise the fascia in front of the rectus muscle similarly.
- Lift both edges of the fascia with Kocker’s forceps and dissect it off the underlying muscle. The dissection must be sharp in the midline.
- Retract both rectus muscles from the midline.
- Incise the peritoneum.
- Apply plastic protection to the edges of the wound and exteriorize the specimen with the central vessels.
- Divide mesentery and bowel at intended location.
- Cut with scissors in the vascular arcade close to the bowel to visualize adequate blood circulation in the oral bowel end (adequate systolic blood pressure during the test?). Move further orally on the colon in case of inadequate bleeding.
- Place the “hat” of the circular stapler with purse-string sutures.
- Interiorize the colon.
- Close the abdomen.
Step 7 – Anastomosis
- Flush the rectum.
- Insert the circular stapler and perforate the bowel with the pin just in front of or behind the staple row.
- Attach oral and anal parts of the stapler while controlling the rotation of the bowel.
- Close the stapler and visually control for possible interposition.
- Flush the anastomosis.
- Test the anastomosis enclosed by water and with air in the rectum.
- Retract the omentum over the small bowel.
Step 8 – Laparoscopic control and closure of ports
- Repeat inspection of the abdominal cavity for possible iatrogenic injury.
- Close the ports.
- The patient is mobilized in the evening the day of surgery, or possibly the next day.
- The patient can carefully start to drink and eat on the first postoperative day.
- The urinary catheter is removed on the first postoperative day or when the patient is mobilized.
- The epidural catheter is usually removed on the continues on peroral analgetics.
- Cardiopulmonary complications depend on the patient´s general condition, comorbidity and the extent of the surgery. Cardial infarction and arrythmias and dysrhythmia may occur. Basal atelectasis and/or pleural fluid and possibly pneumonia are more common.
- Approximately 5% develop anastomosis leakage. Preoperative radiation therapy increases the risk of leakage. Intraperitoneal and/or pelvic infections, diffuse or localized, are rare in the absence of anastomosic leakage.
- Intraabdominal bleeding, including bleeding from anastomosis is relatively rare.
- After open surgery wound dehiscence and infection in the abdominal wound occur to varying degrees, from light superficial infection to abdominal wall abscess.
- Paralytic ileus is common in the presence of another complication, but can also appear without any specific cause.
- Mechanical ileus is relatively rare, but if there is a lack of intestinal activity in the first week and increasing abdominal pains, a mechanical ileus is suspected.
- Port-site hernia occurs after a laparoscopy.
- Deep vein thrombosis and lung embolism are rare if prophylaxis is used according to guidelines.
- Urinary retention.
- Ventral hernia in the abdominal wound may occur.
- Postoperative ileus occurs in about 5%.