approach was favored for many years because it is quick and simple and there is no chance of

anastomotic leak. However, 30% to 50% of patients treated in this way never undergo reversal of the

stoma, and when they do, the complication rate is high (major complications in 5% to 25%, anastomotic

leak in 2% to 30%).64,65

Algorithm 69-1. Diverticulitis Treatment based on Modified Hinchey Score (0–IV).

Despite these problems, this is still the procedure of choice in unstable patients. However, in the more

stable patient who requires an urgent operation because of generalized diverticular peritonitis on

presentation or failure of nonoperative management, the goal should be resection with primary

anastomosis and creation of a diverting stoma, usually a loop ileostomy. The anastomotic leak rate in

patients with free diverticular perforation who undergo a single-stage operation acutely is 13%.66 While

diverting ileostomy or colostomy upstream from a primary anastomosis does not prevent an

anastomotic leak, it lessens the consequences of a leak by diverting the fecal stream from the area,

preventing potentially devastating gross fecal soilage through the defect.

Obstruction

Complete obstruction from DD is unusual. Partial obstruction resulting from edema, spasm, and

inflammation is more common. The differential diagnosis includes cancer and inflammatory bowel

disease. Medical treatment and elective resection are usually successful. Rarely is the placement of a

colonic stent necessary, but it may be used to allow for bowel preparation before a single-stage

resection with primary anastomosis. A diverting stoma may be necessary to relieve obstruction and

enable completion of the workup and treatment before definitive resection. If perforation has resulted

from obstruction, even when the distinction between obstructive cancer and diverticular obstruction

cannot be made, the perforated segment should be resected and diverting end-colostomy performed. If

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this is a right-sided process in a relatively stable patient, primary anastomosis and diverting loop

ileostomy can be considered.

Fistula

The presence of a fistula usually obviates the need for an emergency operation because the abscess has

in effect spontaneously drained internally. A single-stage operation should be planned. The bladder side

of a colovesical fistula is usually disrupted bluntly at the time of colon resection. No repair of the

bladder is needed unless there is a visibly patent opening at the transected fistula tract site. A urinary

drainage catheter is left in place for 7 to 10 days after surgery.46 A cystogram can be done to verify

closure of the tract opening and can facilitate discharge without an indwelling catheter following

laparoscopic resection, which is often earlier than after open procedures. It is not necessary to leave a

pelvic drain at the time of resection. Likewise, fistula tract openings to the vaginal cuff do not require

closure. At most, omentum can be draped into the pelvis to separate the fresh colorectal anastomosis

from the opening on the vagina.

Giant Colonic Diverticulum

Treatment is surgical resection of the involved segment of colon. Planned electively, a single-stage

operation is indicated. Once perforated, the decision process parallels common diverticulitis, preference

being given to resection with primary anastomosis and diverting loop stoma in the stable patient.

MANAGEMENT

Operative Strategies

8 The most important advance in the surgical management of DD besides trying to convert staged,

emergency operations into elective, single-stage operations is the introduction of minimally invasive

surgical techniques. No matter what the approach, certain challenges face the surgeon operating for DD.

Inflammation distorts the anatomic planes. Dense fibrosis and adhesions impede sharp dissection and

make it difficult to get good traction and countertraction that enable dissection. Inflammatory adhesions

interfere with visualization and sometimes even palpation of anatomic structures.

Key concepts apply to both laparoscopic and open procedures. The goal is not to remove every

diverticulum but rather to resect the area of inflammation or complication. The proximal resection line

should be at soft, pliable bowel. The distal resection line must be at the top of the rectum demarcated

by splaying of the bunched longitudinal muscle fibers (taenia coli) into the continuous longitudinal,

outer layer of the rectal muscularis propria. The point of transection is almost never below the anterior

pelvic peritoneal reflection. The splenic flexure should almost always be mobilized to facilitate creation

of a tension-free colorectal anastomosis. The anastomotic site itself must be free from diverticula, which

can be difficult in the patient with dense, pandiverticulosis. Manual, pinch dissection (or “finger

fracture”) techniques are used to separate structures and divide areas of fibrosis and thick adhesions.

Dissection commences away from the focus of inflammation, usually proximal to it. The left ureter

should be identified as early as possible and before transecting major vessels or the colon. In the setting

of severe inflammation in the left lower quadrant or pelvis, it can be very helpful to mobilize and divide

the proximal bowel as an initial operative maneuver. Likewise, when dense inflammation makes the

standard, lateral-to-medial mobilization of the sigmoid difficult, a medial-to-lateral approach can

sometimes provide access to less inflamed tissues. While typically not needed, when a preoperative CT

scan shows dense inflammation in proximity to the left ureter, placement of ureteral stents can help

with ureteral identification and protection during dissection. Whether using open or laparoscopic

techniques, an elective operation should be deferred for 4 to 6 weeks after the last episode of

inflammation so that acute inflammatory changes do not interfere with either the dissection or the

construction of a safe colorectal anastomosis.67

There is growing experience with laparoscopic resection of even complicated DD. A meta-analysis

comparing laparoscopic to open diverticulitis resections concluded that the laparoscopic patients had

lower infection rates (overall and wound); decreased pulmonary, gastrointestinal, and cardiovascular

complications; and a shorter time to recovery of bowel function and hospital discharge. Although

studies in the meta-analysis included acute and chronic indications for surgery and complicated as well

as uncomplicated diverticulitis in both groups, the authors cautioned that the retrospective nature of the

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reviewed studies introduced selection bias.68 When laparoscopic resections for DD are performed early

(2 to 16 days after hospital admission), the conversion rates are higher than when surgery is delayed

(more than 6 weeks).69 Hand-assisted minimally invasive operations may offer significant benefit

compared to pure laparoscopic surgery for DD, showing lower conversion rates, shorter operative times,

and no compromise of the speedy recovery associated with fully laparoscopic operations.70

Elective Surgery

Several observations form the basis of recommendations for elective resection following episodes of

diverticulitis. Forty percent of diverticulitis patients admitted to the hospital will develop a

complication, 23% following a single episode and 58% following two episodes. Thirty to 45% of

patients hospitalized for diverticulitis will have another flare, usually within 5 years (90%). Among

patients hospitalized a second time, only 10% remain symptom-free.71–73 Mortality doubles with a

second flare. The classic indications for elective resection include two or more episodes of documented

diverticulitis, a single episode of complicated diverticulitis (modified Hinchey stage Ib or II), one

documented episode in an immunocompromised patient, one documented episode in a young patient

(40 to 50 years old), and an inability to exclude cancer as the cause of the signs and symptoms.

9 Practice parameters outlined by the American Society of Colon and Rectal Surgeons note that most

patients who present with complicated diverticulitis do so at their first episode, so operating on patients

with uncomplicated episodes of diverticulitis may not reduce the risk of emergency surgery and

mortality. “The age and medical condition of the patient, the frequency and severity of the attack(s),

and whether there are persistent symptoms after the acute episode” may be better determinants of

recommendation for elective resection.61 Complications develop often enough after successful medical

management of complicated diverticulitis to warrant recommending elective resection.56 Kaiser et al.45

reported that 41% of patients treated with percutaneous drainage of a diverticular abscess will later

develop severe sepsis.

It has been noted that the incidence of DD has steadily increased among young people, from 12% in

196974 to 20% in 199875 to 54% in a study of young and obese American patients in 2006.76