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U N I T 8
Gastrointestinal and Hepatobiliary Function
necrosis and movement of blood into the luminal flu-
ids. This promotes rapid growth of bacteria, especially
anaerobes that grow rapidly in this favorable environ-
ment and produce a lethal endotoxin.
54
The manifestations of intestinal obstruction depend
on the degree of obstruction and its duration. The major
symptoms of acute intestinal obstruction are pain, abso-
lute constipation, abdominal distention, and vomiting.
51
With mechanical obstruction, the pain is severe and
colicky, in contrast with the continuous pain and silent
abdomen of paralytic ileus. There also is borboryg-
mus (i.e., rumbling sounds made by propulsion of gas
in the intestine); audible, high-pitched peristalsis; and
peristaltic rushes. Visible peristalsis may appear along
the course of the distended intestine. Extreme restless-
ness and conscious awareness of intestinal movements
are experienced along with weakness, perspiration, and
anxiety. Should strangulation of the bowel occur, there
is a change in symptoms. The character of the pain shifts
from the intermittent colicky pain caused by the hyper-
peristaltic movements of the intestine to a severe and
steady type of pain. Vomiting and fluid and electrolyte
disorders occur with both types of obstruction.
Diagnosis of intestinal obstruction usually is based
on history and physical findings. Plain film radiography
of the abdomen may be used to detect the presence
of a gas-filled bowel. CT scans and ultrasonography
may also be used to detect the presence of mechanical
obstruction.
51
Treatment depends on the cause and type
of obstruction. Most cases of adynamic obstruction
respond to decompression of the bowel through naso-
gastric suction and correction of fluid and electrolyte
imbalances. Strangulation and complete bowel obstruc-
tion require surgical intervention.
Peritonitis
Peritonitis is an inflammatory response of the serous
membrane that lines the abdominal cavity and covers
the visceral organs.
6
It can be caused by bacterial inva-
sion or chemical irritation. Most commonly, enteric
bacteria enter the peritoneum because of a break in the
wall of one of the abdominal organs. The most common
causes of peritonitis are perforated peptic ulcer, ruptured
appendix, perforated diverticulum, gangrenous bowel,
pelvic inflammatory disease, and gangrenous gallblad-
der. Other causes are abdominal trauma and wounds.
The peritoneum has several characteristics that
increase its vulnerability to or protect it from the effects
Small intestine
Peritoneum
Hernial sac
Testicle
C
A
B
FIGURE 29-10.
Three causes of intestinal obstruction.
(A)
Intussusception with invagination
or shortening of the bowel caused by movement of one segment of the bowel into another.
(B)
Volvulus of the sigmoid colon; the twist is counterclockwise in most cases. Note the edematous
section of bowel.
(C)
Hernia (inguinal).The sac of the hernia is a continuation of the peritoneum
of the abdomen.The hernial contents are intestine, omentum, or other abdominal contents that
pass through the hernial opening into the hernial sac. (From Smeltzer SC, Bare BG. Brunner and
Suddarth’sTextbook of Medical–Surgical Nursing. 10th ed. Philadelphia, PA: Lippincott Williams &
Wilkins; 2004:1055.)
