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24 Inflammatory Bowel Disease and Other Types of Colitis 259
can be difficult with inadequate incisions. Let the peripheral extension of the fistula
tract guide you. Just avoid bringing the incision too near the anal orifice. And do not
forget that oral Flagyl may prevent recurrences and offer non-surgical palliation.
Clostridium Difficile Colitis
Although Clostridium difficile colitis (CDC) is not considered IBD, this is an
acute colitis. With the prevalent overuse and misuse of antimicrobial agents by physicians and surgeons, CDC is a too common problem in hospitalized patients. CDC
classically presents with diarrhea and abdominal pain following a history of antibiotic intake, with independent risk factors including age over 65, cephalosporin use,
use of multiple antibiotics, prolonged hospital stay, and use of antibiotics for more
than 7 days. The more antibiotics you give, the higher the chance that your patient
will develop CDC, but it can occur even after a single dose. The tragedy is that pa-
tients may die from CDC after having received antibiotics for dubious indications.
The clinical spectrum of CDC is broad, ranging from mild diarrhea on the
one hand to colonic perforation of the other. The gold standard for diagnosis is
the stool cytotoxin assay for toxin B; however, the test results may take 1–3 days.
Therefore, many institutions use the latex agglutination test, which has a faster
return time but is less sensitive. Or, even faster is sigmoidoscopy, demonstrating
the typical ulceration and pseudomembranes for which the disease was named.
The preferred medical therapy for CDC includes oral metronidazole or oral vancomycin and, if the patient is unable to take oral medications, intravenous metronidazole. These therapies are highly effective in most patients, with only a
minority eventually requiring surgical therapy. However, systemic deterioration
and peritonitis despite optimal medical therapy mandate urgent laparotomy.
A subgroup of CDC patients present from the beginning with an acute abdomen, exposing them to a highly morbid and unnecessary exploratory lapa-
rotomy, which discloses viable and not perforated CDC. Therefore, remember
that in any patient who presents with an acute abdomen with a history of recent
or current antibiotic intake and without findings that mandate an immediate
exploration (e.g., free air), CDC should be urgently excluded. Timely diagnosis of
CDC through the use of sigmoidoscopy or CT scan—showing diffuse colonic wall
thickening and colonic dilatation—will allow adequate medical treatment and
could spare the critically ill patient an unnecessary and risky operation.
At operation for fulminant CDC that failed conservative treatment, the large
bowel appears distended, inflamed, gray, and paper thin; sealed miniperforations
may be present. There is no doubt that subtotal colectomy is the procedure of
choice when the colon is nonviable or perforated. It is also a reasonable option,
260 Per-Olof Nyström
albeit unproven, when operating on a patient with CDC who has failed to improve
on medical treatment. But, whether a subtotal colectomy is advisable during an
exploratory laparotomy in a critically ill patient for an acute abdomen, with a
surprise operative finding of an undiagnosed CDC, is unknown. The construction
of any bowel anastomosis is contraindicated when operating on CDC; the ileum is
exteriorized as an ileostomy, and the rectum closed as a Hartmann’s pouch. When
the patient has recovered, an ileorectal anastomosis can be done. Consider, however, the risk of reactivation of the CDC at the time of stoma closure; remember
that a single antibiotic dose is all it takes.
Summary
In acute UC:
Liaise closely with physician gastroenterologists
Assess extent and severity of colitis and response to treatment
Assess effects of colitis on the overall status of the patient
Operate semielectively and do a total abdominal colectomy
In CD:
Avoid surgery if at all possible
Indications for emergency surgery include Crohn’s colitis, suspected ap-
pendicitis, SBO, and abscess
In surgery for suspected appendicitis avoid resection of CD
In SBO operate only if the gut is truly completely obstructed
Drain abscesses percutaneously and operate later in a planned, elective fashion
In CDC:
Treat medically with metronidazole or vancomycin
Operate if no response; resect but avoid anastomosis
Editorial Comment
This is a good place to discuss neutropenic enterocolitis and ischemic colitis.
Neutropenic Enterocolitis
Neutropenic enterocolitis is a transmural inflammation of the large bowel in
myelosuppressed and immunosuppressed patients, usually suffering from myeloproliferative disorders, receiving chemotherapy or following solid organ or bone
24 Inflammatory Bowel Disease and Other Types of Colitis 261
marrow transplantation. Profound neutropenia appears to be the common denominator. The process involves mucosal damage and alteration in bacterial flora,
which then invade the bowel wall. The cecum is primarily affected, but the process
may extend to the ascending colon and even the ileum. The presentation may
mimic acute appendicitis; watery or bloody diarrhea is present in only half of the
patients. Right lower quadrant tenderness, a palpable cecum, peritoneal signs, and
features of ileus may be present. Neutropenia is a pathognomonic laboratory finding. Plain abdominal X-rays are usually nonspecific, revealing an associated ileus,
but may show thumbprinting of the right colon and intramural air (pneumatosis)—
denoting severe involvement of the cecal wall. CT scan of the abdomen is the di-
agnostic procedure of choice, showing thickening of the cecum and free air if an
underlying perforation exists.
Management should be initially supportive, including broad-spectrum antibiotics effective against colonic Gram-negative bacteria and anaerobes; granulocyte colony-stimulating factor may be considered. Clinical deterioration,
evidence of free perforation, and, rarely, severe lower gastrointestinal hemorrhage may necessitate operation. At laparotomy, normal-looking serosal surfaces
may hide mucosal breakdown and necrosis. Therefore, the whole involved segment of colon should be resected; anastomosis should be avoided in these debilitated patients. Mortality is obviously high. The key is to recognize the
condition and avoid an operation in the majority of patients.
Ischemic Colitis
Ischemic colitis is a poorly defined entity that encompasses a wide variety of
conditions. Paradoxically, occlusion of the named arteries supplying the colon is
not associated with ischemic colitis, but local vascular changes in the wall of the
colon may play a role. Thus, a patient with sigmoid colon gangrene following repair
of an abdominal aortic aneurysm and ligation of the inferior mesenteric artery has
colonic ischemia—not ischemic colitis. But, a patient who undergoes treatment of a
ruptured abdominal aortic aneurysm with preoperative hypotension who develops
gangrene of the right colon postoperatively has ischemic colitis.
Ischemic colitis develops in two different clinical settings:
Spontaneous: in patients with underlying cardiac failure, chronic lung dis-
ease, renal failure, diabetes, and collagen disease—probably related to diseased
intramural vessels
Shock associated: in patients who have experienced sustained shock regardless of etiology (e.g., ruptured aortic aneurysms)
Typically, the colonic process involves a varying depth of penetration.
Transient mucosal involvement may or may not progress to partial thickness
262 Per-Olof Nyström
necrosis, which may recover with or without a stricture or progress to full-thickness gangrene. Although most common in the “watershed” area of the splenic
flexure and the left colon, the disease can involve any part of the colon and the
rectum and rarely the entire colon; although usually focal, it may be patchy or
diffuse.
Patients with spontaneous ischemic colitis present typically with nonspecific abdominal pain and lower gastrointestinal bleeding (hematochezia). Those
with shock-associated ischemic colitis develop these features on top of their un-
derlying critical disease.
As with mesenteric ischemia (> Chap. 23), the clinical picture, as well as
laboratory findings, is entirely nonspecific, as is the commonly associated ileus.
Abdominal X-rays may demonstrate an ileus and colonic dilatation proximal to
the area of ischemia or a dilated ischemic colon. In the rare, advanced transmural cases, pneumatosis coli or free gas may be seen. Findings on CT include colonic wall thickening, free fluid, and pneumatosis coli. Lower gastrointestinal
endoscopy (often bedside) is the best diagnostic test, visualizing a spectrum of
hemorrhagic and ischemic changes that, although nonspecific and that may be
confused with CD colitis (see discussion of CD colitis), are highly suggestive in
the specific clinical setting.
Treatment
Clinical and radiographic evidence of colonic perforation or an endoscopic
picture of dead bowel (black, paralyzed) necessitates a laparotomy and resection
of the involved segment, but this is infrequently needed. Nontransmural ischemia
is managed nonoperatively with supportive measures and wide-spectrum antibiotics as long as the patient is not deteriorating. Increasing or persisting abdominal
pain, fever, ileus, leukocytosis, acidosis, and progressive changes on abdominal
imaging may call for colonic resection.
Although most patients recover from the acute insult, some may progress
to develop a chronic ischemic stricture—but this is beyond the scope of our
story.
Colonic Obstruction
Per-Olof Nyström
The only time human beings wish they could fart and defecate is when they are
not able to do so.
This chapter considers the most common cause of acute obstruction of the
colon—cancer—but also mentions a much less common cause, which is diver-
ticulitis. Also discussed is the condition that mimics obstruction: pseudo-
obstruction or Ogilvie’s syndrome. Finally, the chapter deals with volvulus of
the colon affecting the sigmoid and cecum.
Malignant and Diverticular Colonic Obstruction
The four “steps” you should consider in the approach to patients with me-
chanical colonic obstruction are:
Establish the exact diagnosis
Then, at operation:
Decompress the colon
Resect the obstructing lesion
Decide whether there should be a primary anastomosis or a colostomy
25
Preoperative Diagnosis and Management
The clinical hallmark of colonic obstruction is significant abdominal distention associated with recent onset of constipation and lack of flatus. The obstruction
usually develops gradually over a few days, sometimes on a background of a change
in bowel habit. The usual site of obstructing carcinoma is the sigmoid or left colon.
The sigmoid is also the locus of any obstructing diverticular mass. Right colonic
lesions become obstructing only at the ileocecal junction. Because of the wide caliber of the rectum, cancer here rarely presents with a complete obstruction.
Per-Olof Nyström
Department of Surgical Gastroenterology, Karolinska University Hospital, Huddinge,
141 86 Stockholm, Sweden
M. Schein et al. (eds.), Schein’s Common Sense Emergency Abdominal Surger y,
DOI: 10.1007/978-3-540-74821-2_25, © Springer-Verlag Berlin Heidelberg 2010
263
264 Per-Olof Nyström
Most of these patients are elderly, and because the obstruction may have
affected them for several days, they have not been eating and drinking properly,
so they are dehydrated. Make a thorough examination of the abdomen. It is usually, but not invariably, grossly distended. Be especially observant of signs of
peritonitis, which may indicate a manifest or pending perforation of the colon,
usually proximal to the obstructing lesion. The site of perforation may be a preexisting sigmoid or left colonic diverticulum, but more commonly it is in the
right colon. The right colon and cecum are the widest part of the bowel. They are
also the most distended part with the highest tension of the bowel wall (Laplace’s
law), thus the most likely to perforate. When the ileocecal valve is competent, the
small bowel will be only mildly distended, while massive distension and pressure
affects the right colon. This pressure can tear the circular muscle layer or cause ischemic necrosis with subsequent perforation. Tenderness of the abdomen on the
right side may be a sign of this development. If such tenderness is present and the
abdominal X-ray shows a grossly distended right colon (in excess of 10 cm), then
operation must not be delayed beyond the requirements of resuscitation.
Beware of obstructing cecal cancers. Because of the wide lumen of the
cecum, they tend to present late—only after occluding the ileocecal valve—
with features of distal small bowel obstruction (SBO), which commonly is incomplete and intermittent. Thus, whenever confronting distal SBO, especially
in a “virgin” abdomen (
Plain abdominal X-rays (> Chaps. 4 and 5) usually show a distended colon
because the obstructing lesion is most often in the left colon. When the obstruction is in the right colon, at the cecal area, it can sometimes be difficult to differentiate between small bowel and large bowel obstruction. In long-standing left
colonic obstruction, when the ileocecal valve is incompetent, the small bowel becomes dilated as well. Severely dilated loops of fluid-filled small bowel may then
obscure the distended colon, a picture that may be misinterpreted as partial SBO.
Regardless of the appearances on plain X-rays you must positively confirm the
diagnosis by additional investigation and exclude pseudo-obstruction (discussed
in a separate section of this chapter). What you have to do is document the site of
the obstruction; this can be done either with colonoscopy or a contrast enema.
For reasons explained in > Chap. 4, our bias is against the use of barium in this
situation and in favor of a water-soluble contrast such as Gastrografin. The site of
the obstruction, but not the cause, will usually be evident. At this stage, “obstruction is obstruction”—the management is the same whether it is caused by a carcinoma or, less commonly, a diverticular mass. A preoperative CT scan is not
mandatory but will usually give the diagnosis: a distended colon proximal to a
cutoff point represented by a mass is an indication for operation without the need
for colonoscopy or contrast enema. [Adding a Gastrografin enema to the CT
would help in delineating the transition point! — The Editors] When clinical and
laboratory features are suggestive of carcinomatosis or extensive hepatic
>
Chap. 21), think about cecal cancer.
25 Colonic Obstruction 265
metastatic involvement, CT documentation of the advanced disease allows better
planning of treatment together with the patient and family. You do not want to
operate on a jaundiced patient whose liver is almost replaced with metastases for
the patient surely will succumb to hepatic failure after the operation.
Planning and Timing the Operation
In general, in the absence of signs of actual or impending compromise of
the bowel wall, there is no reason for you to hurry with the operation. Daytime
surgery, with all that it means in terms of the surgical team and supportive personnel, is the better option for the patient and yourself. There is plenty of time to
prepare the patient for a definitive operation to relieve the obstruction. On the
other hand, should the patient have peritonitis, systemic inflammatory response
syndrome (SIRS), or free abdominal gas on abdominal imaging, an emergency
operation is necessary. Antibiotic treatment should be started and the time of the
operation decided according to the progress of the resuscitation-optimization
(> Chap. 6).
Obviously, in patients with colonic obstruction, bowel preparation is contraindicated. Any cleansing solutions administrated from above will accumulate
proximal to the obstruction, further dilating the obstructed colon and making
your life more miserable during the operation. Some surgeons like to administer
enemas to clear the rectum and colon distal to the obstruction, but these sections
of the bowel are usually empty. Again: do not forget to administer the usual dose
of systemic antibiotic prophylaxis just before the operation (> Chap. 7).
In general, the operation for acute colonic obstruction is a major procedure, often in a patient who is old and fragile. Consequently, the mortality and
morbidity of these operations are significant (sorry, no percentages were allowed
by the editors). To avoid complications and mortality, you have to exercise your
best judgment along the lines presented here.
The Operation
A long midline incision is nearly always preferable. The findings of ascites,
peritoneal seedlings, “omental cake,” and hepatic metastases will immediately tell
you that the battle has been lost, and the operation is merely palliative. If the
obstruction is in the right colon, there is usually not a lot of bowel distension.
Then, the operation is a rather straightforward right hemicolectomy with primary
anastomosis.
The left colon or the sigmoid, however, is the usual site of the obstruction. Here,
the proximal colon is distended, making the operation more difficult. First, inspect
the ascending colon to find out if there are tears or necrosis due to the distension.
266 Per-Olof Nyström
If there are, they can be of any stage from minor to large with microperforation. The
significance of the tears is that if they are extensive or necrotic it may suggest that a
subtotal colectomy is indicated. Otherwise, proceed as follows:
Decompression. Because of the distended bowel, it may be difficult to expose
the lesion on the left side and to manipulate the bowel. Sometimes, it is better to
make an enterotomy into the terminal ileum, or even through the appendix, and
insert the suction device (a Poole sucker or a large sump drain) through the hole
to decompress the small bowel and also pass the device through the ileocecal valve
to decompress the right colon. Close the hole transversely with a suture. It should
now be possible to expose the lesion that causes the obstruction. Often, in cases
diagnosed and treated early, the colonic distention is caused by gas and not fecal
matter; it can be relieved simply by inserting a large needle or angiocath connected
to the suction tube and tunneled through the tenia coli.
Resection. Whether it is cancer or diverticulitis-sigmoiditis (> Chap. 26), the
principles of treatment are the same. Mobilize the lesion the same way you would
at an elective operation for cancer and resect it. Watch out for the ureter. If you are
accustomed to linear cutting staplers (e.g., GIA), this is one of the best instances
to use staplers. Transect the bowel on each side of the lesion and divide the mesentery and the segmental vessels with the linear stapler. You have resected the
cause of the obstruction with complete control of the bowel ends and no leakage.
Now is the time to decide whether the bowel ends should be joined or the proximal
end should be brought out as a colostomy.
Do notice that it is considerably more difficult to operate on colonic obstruction than on a similar elective case. You will need the extra hands of an assistant
to achieve exposure, and the decisions are much more complex during the operation. It is advisable to do the operation together with a colleague who can assist
with the decisions [if you are a lonely country surgeon, you will have to be “assisted” by one of those fancy retractors; you can talk to the retractor as well—The
Editors]. If it is a cancer operation, it should be the correct cancer resection, not
just an operation that relieves the obstruction. A “simple” bowel resection is permissible only if the cancer is disseminated so that the type of resection has no
influence on the prognosis of the cancer. In that situation, a colostomy is usually
the better option because it is safer for the patient and has less risk of a new obstruction due to local recurrence of the tumor.
To Anastomose or Not?
The judgment process regarding whether to anastomose is not much different from that considered after sigmoidectomy for acute diverticulitis (discussed in
>
Chap. 26). What is different, however, is that here, usually, there is no associated
25 Colonic Obstruction 267
peritonitis and suppuration. In essence, after you have resected the lesion, you are
left with a few options:
End left colostomy—Hartmann’s procedure
Primary colocolic or colorectal anastomosis
Subtotal colectomy with ileosigmoid anastomosis
If the cancer is situated in the transverse or descending colon, it is often better
to do a subtotal colectomy and an ileosigmoid anastomosis. This usually means
that empty or mildly distended and well-perfused small bowel is joined to normal
colon below the obstruction. Most patients will manage an ileosigmoid anastomosis without incapacitating diarrhea and incontinence, while an ileorectal anastomosis requires that the patient had normal continence before the current illness.
For cancers of the sigmoid colon or rectosigmoid junction, a sigmoid colectomy
is adequate, and a subtotal colectomy should be considered only if the ascending
colon is ischemic or perforated as mentioned.
Some Controversies
The main dispute is the question of primary anastomosis and the means
of obtaining that goal. It is only a problem for left-sided obstructions. On-table
bowel irrigation has been proposed to facilitate primary anastomosis between
clean proximal colon and the rectum. Its value is discussed in > Chap. 26 on
diverticulitis (in the section “Fecology”). The irrigation prolongs the operation
substantially and therefore represents “negative damage control.” An alterna-
tive is the subtotal or total abdominal colectomy with anastomosis of the terminal ileum to the sigmoid colon or rectum. This also is a bigger operation that
takes longer. In a large Scottish randomized trial comparing the two means
(subtotal vs. segmental resection) of obtaining a primary anastomosis, there
was no difference in survival or anastomotic healing with either method
(SCOTIA Study Group 1995). There are now several randomized trials of elective colonic resection with or without mechanical bowel preparation. Again,
there was no difference in anastomotic healing. It may not be entirely valid to
extrapolate the results with “residual feces” of the “elective” colon to the massive
fecal load of the acute colon. It appears, however, that a primary anastomosis
can be made safely on the obstructed colon after decompression and removal
of feces with suction and milking the colonic end before joining it to the rectum. We, among others, make an anastomosis in an “unprepared bowel” in selective cases of obstruction.
Why bother with a primary anastomosis at all when it increases the operation time and complexity of the operation? A Hartmann resection and co-
lostomy are quicker and simpler. It is not an all-or-nothing situation, but the
268 Per-Olof Nyström
concerned surgeon will know that the Hartmann resection is often the better
choice if the patient is in bad general condition or if the cancer cannot be radically removed. About half of the Hartman resections will never be reversed,
often for very good reasons. For the less-experienced surgeon, we suggest that
the Hartmann resection is always a valid option.
Is there any role for a decompressive colostomy without resection of the
obstructing lesion? This staged management was commonly used only a few de-
cades ago, usually consisting of a transverse colostomy as the first stage. Now, we
would consider this option in three circumstances (but also see the discussion of
stents in this chapter):
The critically ill patient who will not tolerate a major procedure; for ex-
ample, a patient developing an obstruction a week after a myocardial infarction.
Here, a transverse colostomy or even cecostomy under local anesthesia will alleviate the obstruction.
When there is preoperative evidence of widespread malignant disease, as
discussed.
[We would also consider a diverting stoma when the obstruction is caused by a rectal tumor. This would allow for a proper staging of the tumor and subsequent elective resection, including, if indicated, adjuvant chemoradiotherapy.—The Editors]
The Colostomy (see also > Chap. 14)
It should be understood that the creation of an emergency colostomy is
potentially problematic. A common problem is retraction due to inadequate mobilization of the bowel. It frequently causes disruption of the mucocutaneous suture line in the early postoperative course, followed by retraction of the bowel end
to a subcutaneous position and progressive stenosis of the skin orifice. Even retraction into the peritoneal cavity resulting in peritoneal soiling with feces occasionally occurs. To be safe, make sure that the left colon has been mobilized up to
and sometimes including the splenic flexure. The closed proximal end should
easily reach several centimeters beyond skin level and rest in that position without support. Do not settle for anything less or you may make the patient’s remaining life an ordeal. The colostomy hole through the rectus abdominis muscle will
have to be larger than normal because of the bowel distension. It is sometimes
necessary to evacuate some of the gas and feces before the bowel can be brought
out. A simple rule of thumb is that when the colostomy hole is kept open with
retractors, the bowel end should pass “easily” between them, and it will not retract
back if the retractors are removed. There is no need to close the lateral gutter or
even to fix the bowel to the anterior abdominal wall if it has been sufficiently
mobilized. Mucocutaneous suture of the colon to the skin with an absorbable
suture is all that is needed.
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