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Miscellaneous Causes of Intestinal Obstruction 413

ent. Other signs of advanced disease, such as rectal bleeding, may
be encountered frequently. This was a presenting feature in 10% of
children with adhesive bowel obstruction in one series from Nigeria. 4
Investigations
The diagnosis of bowel obstruction is usually clinical. In a few patients
who have bowel perforation, plain chest x-ray may show gas under the
diaphragm. Plain abdominal films may show dilated loops of bowel and
multiple air-fluid levels. Prominent valvulae conniventes suggest small
bowel obstruction, and marked haustrations may occur in large bowel
obstruction. However, although these bowel markings readily appear in
adults and older children, they may be absent in infants and younger
children. In fact, it may be impossible to distinguish between small and
large intestines on plain films in infants.
In patients with previous adhesive SBO who have signs of incomplete
obstruction or others in whom the diagnosis is in doubt, a contrast
examination of the gastrointestinal tract is useful, although barium Figure 69.1: Bowel gangrene from postoperative adhesion SBO.
contrast may occasionally cause impaction above the obstruction.
Failure of the contrast to pass into the distal small bowel suggests
intestinal obstruction. The average transit time for oral contrast to
reach the colon is 3–4 hours, but this time could be significantly longer
when there is obstruction. If the patient’s clinical status allows, contrast
progression can be followed by plain x-rays up to 12–24 hours later.
Contrast enema (typically with water-soluble contrast) may be useful in
children with distal obstruction. A complete blood count, grouping and
cross matching, and serum chemistry are done in all patients.
Management
Management involves resuscitation and correction of fluid and electro-
lyte deficits by administration of intravenous (IV) fluids. Nasogastric
decompression is then instituted, and broad spectrum antibiotics may
be started. If the condition does not improve on the above management
after 48 hours, laparotomy should be considered. 8-11 Early operative
intervention is preferred for children, especially infants, because the
already nutritionally compromised child has less tolerance compared Figure 69.2: Dividing the adhesions.
to adults for the 48-hour starvation period. In children who present
with features of bowel strangulation and gangrene, laparotomy should
be undertaken immediately after adequate resuscitation (Figure 69.1).
At operation, adhesions can be single, multiple, or dense. Single
adhesions are divided (Figure 69.2). In patients with multiple adhesions,
it is important to identify all offending bands. Some surgeons believe
that it is important to free the entire peritoneal cavity of all adhesions,
whereas others believe that only the adhesions that obstruct the
intestine should be divided because the other adhesions have fixed the
remaining bowel in an unobstructed position. In most instances, it is
wiser to remove only the offending bands because trauma may trigger
another episode of adhesions. Adhesions are divided sharply, aided
by countertraction from the assistant. Bowel gangrene is a common
4
finding, especially in Africa. In this situation, bowel resection with
end-to-end bowel anastomosis is done (Figure 69.3).
Repeated adhesions can be a major problem, and therefore many
mechanical and chemical approaches have been developed. Internal
stenting using long tubes such as the Baker or Leonard tubes can Figure 69.3: Resection of gangrenous bowel.
be of help, and intestinal plication may help to fix the bowel in the
unobstructed position. Chemical methods have evolved over the years Foreign Bodies and Bezoars
7
to deal with or reduce the incidence of peritoneal adhesions. These
chemical agents include heparin, fibrinolytic compounds, nonsteroidal Foreign bodies (FBs) of the aerodigestive tract can be involved in caus-
anti-inflammatory drugs (NSAIDs), low molecular weight dextran ing intestinal obstruction in children of all ages. There is a tendency for
solutions, antihistamines, prokinetic agents, calcium channel blockers, children to put everything in their mouths, so ingestion of an FB is a
and steroids. As evidenced by the multiplicity of these methods, none major problem, especially in Africa, where poverty and hunger may be
3–7
of these techniques has been shown to completely eliminate the problem contributory. Below the level of the oesophagus and stomach, ingested
of adhesions. Meticulous handling of tissues and careful surgery with the FBs may be impacted in the C-loop of the duodenum, at the ligament of
use of talc-free gloves as well as minimally invasive abdominal surgery, Treitz, Meckel’s diverticulum, or the ileocaecal valve, causing intestinal
where possible, may cause less tissue injury and lead to fewer adhesions. obstruction. Perforation with peritonitis may cause secondary obstruction.