Colorectal surgery

Anatomy or system affected: Abdomen, anus, gastrointestinal system, intestines

Definition: Surgery that is required to correct pathologies of the colon, rectum, and anus

Indications and Procedures

The large intestine, or colon, is shaped like an inverted U. It starts at the lower right side of the pelvis, where the small intestine empties into the cecum. The colon rises from the cecum to the center of the abdomen, crosses to the left, and descends to the S-shaped sigmoid colon, the rectum, and the anus. Common disorders of the colon, rectum, and anus that require surgery are hemorrhoids, Crohn’s disease, ulcerative colitis, cancer, diverticulosis, and diverticulitis.

Hemorrhoids are swollen veins in the lower part of the rectum and the anus. They protrude as nodes or lumps that can cause severe pain, itching, and inflammation. Hemorrhoids can be tied off with tiny rubber bands. After a few days, they fall off painlessly. Medications can shrink internal hemorrhoids, or hemorrhoidal tissue can be removed by photocoagulation, a process that uses electromagnetic energy to eradicate affected tissues. Sometimes, a hemorrhoidectomy is required. This procedure involves the extensive excision of hemorrhoidal tissue and can be quite painful.

Crohn’s disease and ulcerative colitis are chronic inflammatory bowel diseases (IBDs) that can affect the colon. Crohn’s disease usually occurs in the small intestine, although it may be limited to the colon. When Crohn’s disease is severe and restricted to the colon, the surgeon may perform a colectomy and ileostomy. This procedure involves removing the entire lower intestine, rectum, and anus. The anal opening is closed, and a new opening, or stoma, is made in the abdominal wall. The ileum, the lower end of the small intestine, is then attached to the opening. A removable pouch is sealed to the opening to collect fecal matter, which must be emptied manually.

Ulcerative colitis may exist with no symptoms other than an occasional flare-up, or it can be a chronic, serious, or life-threatening disease. It is characterized by a series of ulcers on the inner wall of the colon. Bloody diarrhea, abdominal pain, and painful bowel movements are symptoms. In severe cases, there is danger of perforation of the colon wall or of swelling (toxic megacolon), either of which can be life-threatening. Ulcerative colitis may also be a precursor of colon cancer. In severe cases of ulcerative colitis, surgery is required. Colectomy and ileostomy are the surgical procedures usually performed, but a modern procedure called ileoanal anastomosis may also be used. As in ileostomy, the surgeon removes the entire colon and rectum but leaves the anal sphincter muscles. The ileum is then attached to the anus. This procedure allows the patient to have natural bowel movements and avoids the necessity of the ileostomy pouch.

Cancers of the colon or rectum, called colorectal cancers, are major causes of morbidity and mortality. The possibility of colon cancer is often signaled by the presence of polyps on the lower intestinal wall. Symptoms such as mucus or blood in the stool may alert the physician to look for polyps and determine whether they are likely to become cancerous. Benign polyps are usually removed surgically.

When polyps are likely to become cancerous, and in the presence of actual colorectal cancer, surgery is usually performed to remove diseased tissue. This often requires excising part or all of the colon. Sometimes a colectomy and colostomy are performed, an operation similar to an ileostomy. In this procedure, the diseased sections of the colon, the rectum, and the anus are removed. The anal opening is sealed, and the remaining colon is brought to an opening in the abdominal wall. This opening, or stoma, is fitted with a removable colostomy bag or pouch to collect fecal matter.

Diverticula are small, sac-like pouches that develop in the colon wall, most often in the sigmoid colon. Their presence is known as diverticulosis. These sacs can collect stagnant fecal matter and become inflamed, resulting in diverticulitis. Abscesses and infection may develop. As inflammation progresses or recurs, the wall of the colon thickens, reducing the width of the passage and increasing the possibility of obstruction and distension of the colon. Perforations in the colon wall may develop and cause peritonitis (infection of the membrane that covers the abdomen).

In severe cases, it may be necessary to perform a temporary colostomy. The diseased section of colon is removed, and the rectum and anus are closed. A stoma is made in the abdominal wall and attached to the remaining colon and covered by a pouch to collect fecal matter. After the bowel has healed, the rectum and anus can be reopened and attached to the colon.

Uses and Complications

Patients with permanent ileostomies and colostomies have a hole in their abdomens that is often five or more centimeters (two or more inches) in diameter. Patients are required to wear removable pouches sealed to their stomas to collect fecal matter so that it can be eliminated. The apparatus is cumbersome, and the entire process can be unpleasant enough to cause serious depression in the patient. Patients’ spouses and other family members are often involved in changing and emptying the bags, particularly with older, infirm persons. Ileoanal anastomosis solves some of these problems because it allows natural bowel movements, but it is useful only in certain conditions.

Perspective and Prospects

Modern surgical procedures are often effective in serious colorectal conditions. The success rate of these surgeries for the treatment of cancer is quite high if the cancer is caught before it spreads to other parts of the body. Nevertheless, patients may have to endure the inconvenience of ostomy bags and paraphernalia for the rest of their lives. Ostomy equipment has been improved: better sealing adhesives that prevent slips and leaks, skin barriers to prevent inflammation, and easier-to-use bags. The configuration of belts, bags, and other appliances has been altered to make them more convenient and easier to live with. New surgical procedures that could maintain normal bowel function for more patients, however, would be a major advancement. With the invention of the 3D printer, scientists were hopeful that sensors would indicate the fullness of a bag, any leakage, and implantable cover seals.

Bibliography

Ellison, E. Christopher, and Robert Milton Zollinger Jr. Zollinger’s Atlas of Surgical Operations. 11th ed., McGraw-Hill Education, 2022.

Feldman, Mark, Lawrence S. Friedman, and Lawrence J. Brandt, editors. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management. 11th ed., 2 vols., Saunders/Elsevier, 2021.

Kapadia, Cyrus R., James M. Crawford, and Caroline Taylor. An Atlas of Gastroenterology: A Guide to Diagnosis and Differential Diagnosis. Pantheon, 2003.

Litin, Scott C., ed. Mayo Clinic Family Health Book. 5th ed., Harper Resource, 2018.

Morris, Andrew. "Breaking down the details of colorectal surgery." Mayo Clinic, 11 Aug. 2022, www.mayoclinichealthsystem.org/hometown-health/speaking-of-health/breaking-down-details-of-colorectal-surgery. Accessed 20 July 2023.