Medical management is continued if the patient’s condition is clearly improving as denoted by reversal of signs of toxicity including fever, tachycardia, leukocytosis, abdominal pain, and colonic distention. Return of bowel function and cessation of hematochezia are favorable signs. As improvement continues, treatment of the underlying cause of the colitis is maximized, oral intake is begun, and intravenous therapy is changed to oral agents. If tolerated, the patient is discharged and followed closely in the outpatient setting.

Patients may reach a plateau after institution of medical therapy. This clinical scenario is characterized by initial reversal of some of the signs of toxicity but failure to resolve other parameters. For instance, the colonic distension may decrease, but tachycardia may persist despite adequate fluid resuscitation. Often a fluctuating clinical picture of possible improvement is followed by laboratory or clinical examinations suggesting worsening of the patient’s condition. When this pattern is observed, the decision to operate is difficult. Patients are sometimes reluctant to consent to a major operation on an urgent basis, but surgeons bear the responsibility of intervening before a life-threatening complication such as perforation occurs. In our experience, illusory improvement really is no improvement and is an important indication for urgent surgery. Our rule of thumb is to operate if the response to medical therapy has reached a plateau persisting more than 24 to 48 hours.

Immediate operative intervention is indicated for the patients whose clinical condition deteriorates. This may be denoted by increased leukocytosis, increased tachycardia, persisting fever, inadequate urine output, confusion, progression of colonic distension, or development of localized or generalized peritonitis.

The proximal end of the rectosigmoid colon is exteriorized to decompress the remaining colon and rectum. This second stoma is placed either at the inferior edge of the midline incision or in a separate lower abdominal site. This avoids placement of a high-risk suture or staple line in the pelvis and makes subsequent colostomy closure technically easier because the distal bowel is easily identified and pelvic tissue planes are left undisturbed. Advocates say this makes mucous fistula the safest and preferred option. But, this approach leaves the patient with a second stoma and is associated with an increased incidence of wound infection, especially if the mucous fistula is placed in the midline wound.

To avoid a second stoma while maintaining the advantages of minimizing the risk of pelvic sepsis and easier subsequent reoperation to restore bowel continuity, some surgeons advocate a modification of mucous fistula in which the closed end of the distal bowel is placed in a subcutaneous location at the site of the ileostomy, the inferior aspect of the midline wound, or a remote site. In the event of a suture line dehiscence, the bowel opens in a controlled, subcutaneous location, thus creating a mucous fistula.

While mucous fistula or subcutaneous exteriorization of the bowel may be technically easy to perform in the patients with a relatively healthy sigmoid colon, many patients requiring emergent colectomy for toxic megacolon will have severe disease throughout the abdominal colon. The diseased bowel and mesentery are foreshortened, edematous, and dramatically inflamed, making it technically difficult to mobilize the distal bowel to the abdominal wall. More importantly, the need to preserve enough length of the rectosigmoid to reach the abdominal wall to create the mucous fistula risks persisting toxicity, perforation, or hemorrhage from the severely diseased, albeit defunctioned, rectosigmoid. It is for these reasons that we generally close the rectum and leave it in situ as a Hartmann pouch. Neither sutured closure nor stapled closure has proved to be superior, although, in reality, the edematous bowel is rarely amenable to stapled closure only. We generally oversew the staple line. Despite the presence of a high-risk suture or staple line, the risk of rectal stump leak (“stump blowout”) remains relatively low (between 2% and 12%) and can be minimized further if a few simple precautions are followed. Placement of the suture or staple line intraperitoneally, as opposed to low in the pelvis, may decrease the rate of leakage and avoids a pelvic dissection. Prior to closing the abdomen, the Hartmann pouch can be decompressed via proctoscopy and a drain (usually a soft red rubber catheter or Foley catheter) can be placed transanally to maintain decompression of the rectal stump. In the event of a stump leak, the resulting pelvic abscess can often be managed by percutaneous catheter drainage.

Today, diversion procedures alone (ileostomy, cecostomy, or an ileostomy with transverse decompressive colostomy, the so-called Turnbull “blowhole” operation) are almost never used because of their high rates of mortality and morbidity and their failure to allow the patient to regain health. A total proctocolectomy and ileostomy is sometimes performed for toxic megacolon or toxic colitis if the rectum is the source of life-threatening hemorrhage or if the rectal disease is severe and/or there is no consideration of subsequently performing a restorative ileal pouch–anal anastomosis procedure. This particularly applies to the patients with severe rectal Crohn’s disease. Before a proctectomy is included as part of the emergency operation, the surgeon must be certain that the patient can tolerate the added morbidity from the additional dissection and additional anesthesia time required to complete the proctectomy.