What is Diverticulitis?
At least 40% of Americans over the age of 60 will develop a condition called diverticulosis. In this condition the muscular contractions of the colon, in order to remove the hard stool, generates so much force that the lining of the colon is squeezed through a tiny hole in the muscle caused by a penetrating artery resulting in a little bubble on the outside of the colon (analogy would be if one took a tire with an inner tube and cut a nickel-sized hole in the tread then pressurized the tire. The inner tube would protrude through the tread hole making a small bubble). Diverticulosis is most common in the sigmoid colon which is the colon portion in the left lower quadrant just above the rectum.
In a small percentage of people something will plug the neck of the diverticulum. When this happens the bacteria trapped inside continue to grow and build up pressure until the diverticulum bursts usually causing a small contained abscess on the outside of the colon. Rarely it will result in a large abscess (an inch or greater in diameter). Even more rarely it will burst freely causing stool to leak into the abdomen requiring emergency surgery and often a temporary colostomy.
Most of the time diverticulitis will respond to a combination of oral antibiotics such as ciprofloxacin and Flagyl. Large abscesses can often be drained by the radiologist with a CT guided catheter placement through the skin and into the abscess to allow the pus to be drained.
For patients with repeated attacks, large abscesses, or certainly a free perforation into the abdomen, surgery is required. Surgery for diverticulitis on an elective basis often involves a laparoscopic removal of the sigmoid colon with reconnection of the descending colon to the top of the rectum. In approximately 90% of cases this is curative and there will be no more severe attacks of diverticulitis.
The operation involves making three small incisions in the abdomen, mobilizing the sigmoid colon from its attachments, clipping and dividing the blood vessels that feed the segment and then dividing the sigmoid colon where it attaches to the rectum. One of the small excisions is extended just large enough to allow the surgeon to remove the diseased colon. The end of a stapling device is then put in the open end of the bowel and sewn in place. It is dropped back within the abdomen. This incision is closed and then a stapling device is inserted through the rectum connect to the “Anvil” in the opening of bowel. It is then tightened and fired reconnecting the colon to the rectum. This connection or anastomosis is then checked a number of ways to be sure that the seal is airtight prior to the completion of the procedure.
Surgical Preparation for Diverticulitis
Preparation for elective surgery for diverticulitis is similar to that for colon cancer although the preoperative CEA is not necessary. Other preoperative tests such as basic blood work or reservation of blood in case it is needed, EKG and chest x-ray are performed commonly. For elective surgery mechanical and antibiotic bowel prep are usually employed. Postoperative care instructions are identical to those from colon resection for colon cancer.