Despite major advances in the medical treatment of ulcerative colitis (UC), surgery is still frequently required. Because the aim of surgery is to cure the disease, elimination of all colorectal mucosa is ideal. This operative strategy may need to be modified depending upon patient-, disease-, and treatment-related factors, which may have an impact on short- and long-term outcomes, as well as quality of life.
Evolution of Surgery for Ulcerative Colitis
Surgery for UC evolved from the initial description of a colostomy in the late nineteenth century, through appendicostomy or cecostomy, to ileostomy with or without a blowhole colostomy, especially for toxic megacolon. Total abdominal colectomy with an ileorectal anastomosis subsequently developed as a technique that allowed resection of diseased colon without a stoma. However, patients who undergo this procedure have ongoing symptoms from proctitis, function is unpredictable, and there is an increasing risk of cancer in the rectum. These disadvantages precluded widespread adoption of the ileorectal anastomosis and raised questions about its durability. Total proctocolectomy with end ileostomy allows the elimination of all diseased mucosa, but it includes a permanent external appliance. The continent ileostomy developed as an alternative. This procedure involves construction of an ileal pouch, made continent by a valve in the efferent limb, and anastomosed to the abdominal skin. It was not too much of a leap to use the anal sphincters instead of a valve and to anastomose the pouch to the anus instead of the abdominal skin. Construction of this ileoanal pouch allows removal of all diseased mucosa but maintains per anal defecation. It has become the standard surgical procedure for the treatment of UC.
Indications for Surgery in Persons with Ulcerative Colitis
Failure of medical treatment: The presence of intractable symptoms despite maximal medical therapy is a common indication for surgery. Failure of medical treatment also may be due to an inability to tolerate a reasonable maintenance dose of antiinflammatory medications that help patients avoid the development of drug-related adverse effects or an overall poor quality of life.
Complications: Emergency surgery may be required for acute complications such as severe acute or fulminant colitis, toxic megacolon, perforation, and hemorrhage. Stricture, dysplasia, and cancer are long-term complications that also may require surgery.
Cancer: The risk of colon cancer in a patient with chronic UC has been estimated to range from 2% at 20 years after onset of disease to 43% at 35 years. The findings of a meta-analysis suggested a cumulative incidence of colorectal cancer of 8.5% at 20 years and 17.8% at 30 years. Patients begin colonoscopic surveillance with biopsies at about 8 years after the onset of their disease. When dysplasia is detected and confirmed by pathologic review, factors such as the location, type, and degree of dysplasia, its extent, and the severity of associated background colitis determine the cancer risk. Adenomatous dysplasia such as that found in a discrete adenoma is not necessarily an indication for colectomy as long as the adenoma can be treated endoscopically.
Other: Extraintestinal manifestations of ulcerative colitis and growth retardation in children are other occasional indications for surgery.
Operations for Ulcerative Colitis
An ileostomy may be temporary or permanent. Temporary fecal diversion may protect a distal anastomosis, be part of the first stage of a proctocolectomy in a sick patient, or be part of the treatment of a pouch complication. A permanent ileostomy may be needed when an insoluble distal pouch problem exists, when a patient is not fit to undergo a staged proctectomy and creation of a pouch, or most commonly after a total proctocolectomy (TPC).
Straight Ileoanal Anastomosis
A straight ileoanal anastomosis, which was initially performed in the 1940s, was associated with high rates of fecal urgency and frequency, leading to low overall satisfaction and problems with continence. These outcomes, which are expected in the absence of a fecal reservoir, along with the anastomotic complications of the procedure, led to the creation of an ileostomy in a significant proportion of patients. A variation of the straight ileoanal anastomosis in which multiple 3- to 4-cm longitudinal myotomies are performed at three circumferential sites has been reported to have comparable function to the ileal pouch–anal anastomosis (IPAA) except for nocturnal soiling.
A subtotal colectomy and ileostomy is the procedure of choice for toxic colitis or megacolon. It is less extensive than a proctocolectomy but avoids the risks associated with pelvic dissection and the creation of an anastomosis. It is therefore suitable for a first-step procedure in malnourished or moribund patients and in those receiving large doses of steroids or immunosuppression, as well as when potential problems with sexual dysfunction or fertility need to be minimized. Performing a subtotal colectomy rather than a one-stage restorative proctocolectomy is safer when a diagnosis of Crohn disease cannot be excluded because it provides a large specimen for histologic evaluation and preserves options for definitive treatment.
During a subtotal colectomy, preservation of the main trunk of the inferior mesenteric artery with division of the mesenteric branches minimizes damage to the autonomic nerves and allows easier identification of the stump when a subsequent proctectomy is performed. Having a longer distal stump also allows the stapled end to reach the anterior abdominal wall for subcutaneous placement. Subcutaneous rather than intraperitoneal stump placement avoids the possibility of rectal stump blowout, which can cause peritonitis or a pelvic abscess and necessitates a repeat laparotomy. If the rectosigmoid stump is very friable, it is matured primarily as a mucus fistula or secondarily after 10 days of hanging out of the wound as a “tail” that is 10 cm in length and wrapped in gauze. If a repeat anastomosis is not intended, it is best to complete a proctectomy soon because the development of a stricture in the rectal stump as a result of persistent inflammation may prevent adequate surveillance.
Abdominal Colectomy with Ileorectal Anastomosis
A colectomy with ileorectal anastomosis (IRA) is technically simple and leads to rapid recovery, but bowel function is dependent upon the distensibility of the rectum, the severity of residual disease, and the adequacy of the anal sphincters. Transection of the rectum should be performed at the level of the sacral promontory to preserve the full length of the rectum for optimal capacity. An ileosigmoid anastomosis is an alternative when the distal sigmoid is spared from active disease. The risk of cancer in the rectum is 3% to 8% over long-term follow-up, and the overall failure rate for an IRA reaches 54% over 20 years. The main advantage of an IRA is that it avoids the hazards of pelvic dissection and thus merits consideration in specific circumstances. It allows restoration of health, completion of education and pregnancy in some young patients prior to a subsequent restorative proctocolectomy, and may be the definitive procedure in elderly patients who do not want to undergo an ileostomy. One-stage surgery is usually performed unless the patient has toxic colitis, intra-abdominal sepsis, and significant malnutrition or unless doubt exists with regard to the normality of the rectal mucosa. In some circumstances, resection of diseased colon at an initial subtotal colectomy may allow recovery of function and compliance of the rectum, which then becomes usable. Favorable results have been reported after primary or secondary IRA, even when proctitis is present. The key aspect of functionality is rectal compliance, which is best judged by rigid proctoscopy. Anastomotic complications are similar whether the ileum is anastomosed to diseased or macroscopically normal rectum, and a routine proximal ileostomy is not indicated. Equivalent results have also been reported with both sutured and stapled anastomoses. The rectum needs to be monitored with yearly surveillance because cancer has been reported to occur in both nonfunctioning and functioning rectums.
Ileostomy and Blowhole Colostomy
The Turnbull blowhole colostomy and loop ileostomy described in the 1960s has a role in extremely ill patients and in situations in which colonic mobilization is hazardous, such as a contained perforation, pregnancy, or a high-lying splenic flexure. The main advantage of the procedure is that the colon is not disturbed; the main disadvantage is that the diseased colon is left behind and may lead to persistent toxicity. The procedure is contraindicated in patients with free perforation or bleeding. A definitive procedure is performed after the patient has recovered.
Total Proctocolectomy and Ileostomy
A TPC with a Brooke ileostomy is curative and is reported to be associated with good quality of life. However, the need for an external appliance, with the complications of leakage around the bag, skin rashes and infections, potential psychosocial issues, and problems with healing of the perineal wound, are disadvantages. Quality of life may be better after an IPAA than with an ileostomy. A TPC and ileostomy is undoubtedly the best option for patients with poor anal sphincter function and for patients who want to address their disease in the least complicated manner with one operation and a minimal chance of needing another operation. A single-stage procedure is avoided in patients with fulminant disease, toxic megacolon, and severe malnutrition or perianal sepsis. Although a subtotal colectomy is the procedure usually performed for severe colonic hemorrhage, a total proctocolectomy occasionally may be indicated for patients with significant rectal hemorrhage.
Proctectomy Surgical Technique
After the colectomy is completed, the rectum may be dissected within the mesorectum to avoid damage to autonomic nerves, but this dissection is associated with greater blood loss. Dissection in the avascular plane between the investing layer of fascia of the rectum and the presacral fascia to the lower border of the third sacral vertebra followed by dissection close to the rectal wall results in less loss of blood and still preserves the pelvic nerves. The lateral rectal dissection is kept close to the rectal wall at the level of the lateral ligament. Anteriorly, the rectal dissection is carried out on the rectal side of the fascia of Denonvilliers, exposing the vertical muscle fibers of the rectum but not the seminal vesicles, and the perineal proctectomy is completed with use of the endoanal technique. An intersphincteric dissection is performed, preserving the anal skin, external sphincter, and levator muscles, because this approach has been reported to be associated with a lower incidence of impotence and a low rate of unhealed perineal wound. Primary closure of the perineal wound is then performed. Alternatively, the anus may be removed completely or not at all. The rectum can be transected at the level of the levators, closing the rectal stump by sutures or staples and thus avoiding a perianal wound altogether. A mucosal proctectomy with or without closure of the anorectal stump has also been proposed.
Up to 11% of patients may have an unhealed perianal wound that is managed by serial wound curettage and cautery, resurfacing with skin grafting, or filling of cavities with vascularized pedicle muscle grafts such as gracilis, semimembranosus, rectus abdominis, or omentum. An inferior gluteal myocutaneous graft has also been used. When a proctocolectomy is performed in the acute setting, it is associated with high mortality and morbidity rates. Pelvic dissection may lead to a pelvic abscess, an enteric fistula, or autonomic nerve damage.
Developed by Nils Kock, the continent ileostomy procedure provides freedom from the need for an external appliance. It consists of the creation of an ileal reservoir (pouch), which is connected to the skin of the abdominal wall by a spout. By intussuscepting the bowel, a nipple valve is created at the exit of the spout from the pouch; it is stabilized by sutures or staples. This valve prevents leakage of stool. Stool is evacuated by the intermittent insertion of a drainage catheter though the flush ileostomy into the pouch. The pouch consists of an S-shaped reservoir made of three 15-cm limbs of small bowel and an exit conduit containing the valve. Patients with UC who are not candidates for an IPAA, who prefer to avoid an IPAA, or whose IPAA fails are potential candidates for the procedure. In the latter case, the initial pouch can be modified for use as the continent ileostomy pouch. Although most patients who undergo the continent ileostomy procedure have a good quality of life, long-term pouch revision and excision rates are high, predominantly because of slippage of the nipple valve. Various modifications have been described to help anchor the nipple valve and prevent slippage, but approximately 20% to 25% of patients still require a repeat operation for valve slippage, prolapse, and incontinence.
The restorative proctocolectomy procedure, developed in the 1970s, is currently the gold standard operation for patients with UC who are undergoing surgery. The components of this procedure are total colectomy, proctectomy, and construction of an ileal reservoir with the creation of an IPAA. A compliant sac made up of loops of small bowel constitutes the reservoir. The procedure may be performed in one, two, or three stages, and the pouch-anal anastomosis is either stapled or hand sewn. In the stapled procedure, the anal transitional zone is preserved and anastomosis is performed 1 cm above the dentate line. Annual biopsy surveillance of the anal transitional zone is then performed. Patients who are poorly compliant at follow-up and those with marked extraintestinal manifestations of UC are best treated with an anal mucosectomy and a hand-sewn anastomosis.
A restorative proctocolectomy can be performed with acceptable complication rates, functional outcomes, and quality of life and is applicable to several subgroups of patients. Satisfactory function has been reported in children younger than 10 years and also in elderly persons as long as they have reasonable sphincter function. In indeterminate colitis, the short- and long-term results are similar to those with UC; however, such patients who are then diagnosed with Crohn disease have worse outcomes. IPAA has also been performed in patients in whom colorectal carcinoma complicates inflammatory bowel disease, although deterioration in the function of the pouch occurs when such patients undergo radiotherapy.
Pouch Configuration and Anastomosis
It is generally agreed that functional results of IPAA are the same regardless of the pouch configurations (J, S, or W). Evacuation disorders are more common with the S pouch if the exit conduit is longer than 2 cm because this configuration may lead to obstructive defecation. The J pouch configuration is the most popular because of the simplicity of its construction. Some controversy exists regarding the influence of anastomotic technique on pouch function. A stapled IPAA is associated with a lower incidence of sepsis and stretch-induced sphincter trauma and preserves the anal transitional zone. The stapled anastomosis functions better, has fewer complications, and is associated with a lower pouch excision rate.
Staging the Procedure
For carefully selected patients in whom the risk of anastomotic leak is likely minimal, the procedure can be performed without a diverting stoma (in one stage). However, an anastomotic leak can lead to significant morbidity and potentially affects long-term pouch function, predisposing to pouch failure. Thus, in the majority of instances, a two-stage procedure is preferable in which the ileoanal pouch is protected with a temporary loop ileostomy because the ileostomy reduces the consequences of an anastomotic leak. Patients with inactive or mild colitis and those for whom steroids have either been discontinued or tapered to a low dose are candidates for such an approach. For patients with more florid colitis and those taking high-dose steroids or potent immunosuppressive medication and anti–tumor necrosis factor agents (which may predispose to post-IPAA septic complications), a three-stage approach is safest. An initial subtotal colectomy minimizes disease and allows the withdrawal of medication and improvement of nutrition before a subsequent completion proctectomy and IPAA. This approach has reduced surgical risks and improved long-term pouch retention.
Technique of Creation of an Ileoanal J Pouch
Standard oral and mechanical bowel preparation is undertaken before creation of an ileoanal J pouch. The operation begins with a midline incision for open surgery or port placement for laparoscopy, after which the colon is mobilized from the pelvic brim proximal to the middle colic vessels, which are preserved. High ligation of the inferior mesenteric vessels is then performed. Dissection is continued into the pelvis using electrocautery in the plane between the presacral fascia and the investing fascia propria of the rectum. Dissection in this plane is then carried down to the pelvic floor, after which the distal rectum is stapled across 1 cm above the dentate line. A J pouch 20 cm in length is fashioned from the distal ileum through the use of staples and is anastomosed to the anal canal proximal to the dentate line. In some circumstances in which problems may exist with reach of the pouch to the anal canal, the S-shaped design allows the pouch to reach an extra 2 cm. The pouch-anal anastomosis is completed with the use of circular stapling device for a stapled anastomosis. When a hand-sewn anastomosis is performed, mucosectomy of the anorectal remnant is completed prior to anastomosis.
Problems with Reach of the Pouch
Minimal information is available on the rate of abandonment of IPAA as a result of technical difficulties; in two reported series, this rate has been suggested to be 4.1% and 6%. The reach of the pouch is influenced by the length of the superior mesenteric artery, the orientation of the small bowel, and the anatomy of the pelvis and mesentery. Problems with pouch reach are traditionally considered to affect tall patients and those with a high body mass index, especially when they are men. Weight loss before surgery may be helpful. Some maneuvers at the time of surgery may facilitate reach of the pouch to the anal canal. These maneuvers include high ligation of the ileocolic vessels, release of the small bowel mesentery from the retroperitoneum, mobilization of the duodenum, excision of the redundant mesenteric tissue lateral to the superior mesenteric vessels (“gib-sail”), and the creation of peritoneal-releasing incisions along the mesenteric edge of the small intestine. Although ligation of some of the branches or of the main trunk of the superior mesenteric artery itself have also been described, this maneuver is associated with a risk for compromise of blood supply to the entire small intestine.
Difficulty with reach of the pouch to the anal canal needs to be anticipated prior to rectal transection so the operation may be modified accordingly to facilitate an ileal pouch rectal anastomosis. Prior to transection of the rectum, a pouch is simulated and the most dependent portion eventually destined to connect to the anal canal is held in a Babcock forceps and delivered into the pelvis. The simultaneous passage of a gloved finger into the anal canal allows confirmation of reach of the Babcock forceps to the intended level of rectal transection. Alternatively, if the apex of the small bowel reaches below the symphysis pubis, then an IPAA is likely to be feasible. If the signs point to a problem with reach, the rectal stump may be intentionally left slightly long to minimize tension on the IPAA. Orientation of the pouch in such a way as to direct the pouch mesentery anteriorly may produce less tension on the anastomosis. When preliminary assessment suggests that these efforts will fail, consideration may be given to the creation of an “S” instead of a “J” pouch. In the rare circumstance in which the pouch has been created but cannot then be mobilized adequately for anastomosis to the anal canal, the end of the pouch may be closed off. The pouch is then sewn in the pelvis and diverted with a proximal ileostomy. After 2 years, an IPAA may be attempted again in the hope that mesenteric lengthening has occurred.