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1004 PART 9: Gastrointestinal Disorders

to identify predictive factors that could be applied to decide when such
patients would benefit from an early colectomy. 61,80-82 Certain factors
such as lactate level of 5.0 mmol/L or greater, WBC >37 or >50, use
80
61
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of preoperative vasopressors, preoperative single or multiorgan failure,
and immunosuppression have been identified as predictive of mortality.
While there are no prospectively validated data to confirm the clinical
utility of these factors, it is the opinion of the authors that after the
initial resuscitation and institution of antibiotic therapy of patients with
CDI admitted to the ICU, any new onset or worsening of existing organ
failure, increasing lactic acidosis, increasing WBC, or the requirement
for vasoconstrictor medications for support should prompt consider-
ation of surgical therapy, with a lower threshold applied to those who
are immunocompromised.
The gold standard surgical treatment for severe CDI currently is a
total abdominal colectomy with sparing of the rectum and creation of
an end ileostomy. Unfortunately, this operation is associated with high
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mortality and morbidity. In a retrospective analysis of the Quebec 2003-
2005 CDI outbreak series, following adjustment for several confounders,
the group undergoing this surgery had lower mortality (adjusted odds
ratio of 0.22; 95% CI, 0.07-0.67; p = 0.008) versus those managed non-
operatively ; but the 30-day mortality for the surgical group was 34%! A
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recent long-term follow-up study of patients treated with colectomy for
CDI found 1-year, 2-year, 5–year, and 7-year mortality of 68.5%, 79.6%,
88.9%, and 90.7%. In an effort to improve outcomes, another surgical
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technique—a diverting loop ileostomy and colonic lavage—has recently
FIGURE 104-5. Abdominal CT with classic findings of C difficile including diffusely thick- gained favor. A preliminary study using this new approach suggested a
ened colon and ascites. (Used with permission of LN Tremblay, MD.) much lower early mortality of only 19%. Further studies are ongoing to
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better define the optimal surgical approach. 83
the diagnosis is suspected and not delayed for laboratory confirmation. INTESTINAL OBSTRUCTION
Antiperistaltic agents should be avoided as they may obscure symptoms
and precipitate toxic megacolon. Also, appropriate infection control Intestinal obstruction develops when air and secretions are prevented
measures including glove and gown contact precautions for the duration from passing normally as the result of mechanical blockage. Mechanical
of the diarrhea, hand hygiene compliance, and private rooms for CDI blockage can occur due to extrinsic compression of the bowel, or intrin-
patients should be instituted. sic obstruction from an abnormality of the bowel wall or intraluminally
In addition to these standard therapies, multiple adjunctive thera- (see Tables 104-5 and 104-6).
pies have been proposed but generally lack sufficient evidence to Obstruction can occur at any point along the entire gastrointestinal
recommend. For example, both the US and European guidelines state tract from oropharynx to anus. It is classified in a number of important
there is no role for the use of probiotics in the treatment or preven- ways that direct management:
tion of CDI. 43,71 Similarly the data on the effectiveness of IVIG are not • Anatomical location (ie, esophageal, gastric, small bowel, colonic)
particularly compelling and until sufficient evidence is available its
use is not recommended. In vitro and animal data showed that both • Complete or incomplete
cholestyramine and colestipol bind the toxins produced by C difficile. • Mechanism (ie, adhesions, masses, hernia, volvulus)
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Unfortunately, these agents also bind vancomycin, thereby decreasing Additionally, for obstruction caused by hernias, it is important to
the amount of active drug available. Given the lack of evidence and the determine whether the contents of the hernia (ie, the portion of the
current recommendation for vancomycin as first-line therapy for severe intestine stuck in the hernia sac) are incarcerated (cannot be reduced
CDI, anion-exchange resins are not recommended. Fecal transplanta- to their normal anatomical location with physical manipulation) or
tion is another treatment that has recently shown promise for recurrent strangulated (compromised blood flow resulting in bowel ischemia).
CDI, but it similarly at present has no role in acute severe CDI. Obstruction can occur at a single point in the bowel or at two points in
There are a number of antibiotics whose role in CDI is evolving.
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Nitazoxanide, an antiprotozoal drug, has been shown to be at least as a loop, termed a closed-loop obstruction. A closed-loop obstruction can
occur (1) within hernias where the bowel is obstructed at the entrance
effective as both metronidazole and vancomycin in small randomized and exit point of the hernia, (2) with adhesive obstructions where
controlled trials. 73,76 Although not available in the United States, the
use of teicoplanin is endorsed by both US and European guidelines as
being equally efficacious to vancomycin and metronidazole. Rifaximin TABLE 104-5 Causes of Small Bowel Obstruction in Adults
is an antibiotic with minimal absorption in the gastrointestinal tract Extrinsic Intramural Intraluminal
after oral administration that has been reported to be effective against
C difficile. Fidaxomicin is a new nonabsorbed macrocyclic antibi- • Tumor • Tumor
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otic that has recently has been approved by the US Food and Drug • Adhesion • Stricture • Gallstone
Administration for treatment of C difficile, with studies suggest it • Hernia • Hematoma • Foreign body
is noninferior to oral vancomycin in mild to moderate CDI cases. 78 • Tumor, metastatic disease • Intussusception • Bezoar
Surgical Surgical therapy for CDI is indicated for toxic megacolon, • Volvulus • Enteritis • Worms
perforation, failure of medical therapy, and fulminant disease. While • Abscess, hematoma
the former two indications are relatively easy to identify, the latter two • Pancreatic pseudocyst
can be more difficult. Clinical response to medical therapy may take • Drains
48 to 72 hours to manifest. Multiple retrospective series have sought • Tight stoma
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