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test for the assessment of Helicobacter pylori status. Diagn Microbiol
Infect Dis. 2004;48: 145–147.
Lew E. Peptic ulcer disease. In: Greenberger RBN, Burakoff R, eds.
Current Diagnosis and Treatment: Gastroenterology, Hepatology, and
Endoscopy. Columbus, OH: McGraw-Hill, 2009:175–183.
Li-Ling J, Irving M. Therapeutic value of octreotide for patients with severe
dumping syndrome–a review of randomised controlled trials. Postgrad
Med J. 2001;77: 441–442.
McColl KE. Clinical practice. Helicobacter pylori infection. N Engl J Med.
2010;362:1597–1604.
Moller MH, Shah K, Bendix J, et al. Risk factors in patients surgically treated
for peptic ulcer perforation. Scand J Gastroenterol. 2009;44:145–152, 2 p
following 152.
Mort JR, Aparasu RR, Baer RK. Interaction between selective serotonin
reuptake inhibitors and nonsteroidal antiinflammatory drugs: review of
the literature. Pharmacotherapy. 2006;26:1307–1313.
Roviello F, Rossi S, Marrelli D, et al. Perforated gastric carcinoma: a report
of 10 cases and review of the literature. World J Surg Oncol. 2006;4:19.
Sarosi GA Jr. Dumping Syndrome. In: Johnson LR, ed. Encyclopedia of
Gastroenterology. Academic Press, San Diego, CA, 2003:634–636.
Shan YS, Hsu HP, Hsieh YH, et al. Significance of intraoperative peritoneal
culture of fungus in perforated peptic ulcer. Br J Surg. 2003;90:1215–
1219.
Sharma SS, Mamtani MR, Sharma MS, et al. A prospective cohort study of
postoperative complications in the management of perforated peptic
ulcer. BMC Surg. 2006;6:8.
Silen W. Cope’s Aarly Diagnosis of the Acute Abdomen. 19 th ed. New
York: Oxford University Press, 1996:xiv, 315 p., 24 p. of plates.
Siu WT, Leong HT, Law BK, et al. Laparoscopic repair for perforated peptic
ulcer: a randomized controlled trial. Ann Surg. 2002;235:313–319.
Svanes C, Lie RT, Svanes K, et al. Adverse effects of delayed treatment for
perforated peptic ulcer. Ann Surg. 1994;220:168–175.
Wolfe MM, Lichtenstein DR, Singh G. Gastrointestinal toxicity of
nonsteroidal antiinflammatory drugs. N Engl J Med. 1999;340:1888–
1899.
Wong CH, Chow PK, Ong HS, et al. Posterior perforation of peptic ulcers:
presentation and outcome of an uncommon surgical emergency.
Surgery. 2004;135:321–325.
Yamada TA, Alpers DH, Kaplowitz N, et al. Textbook of Gastroenterology.
4th ed. Philadelphia, PA: Lippincott Williams & Wilkins, 2003.
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19
Small Bowel Obstruction
SARA E. CLARK and LILLIAN G. DAWES
Presentation
A 78-year-old man with a history of hypertension,
diabetes, and coronary artery disease presents with a
2-day history of diffuse abdominal pain, nausea, and
several episodes of emesis. He has not been able to
tolerate any oral intake. His bowel movements have
been normal up until the previous day when he had a
liquid bowel movement. He has not had any flatus for at
least 2 days. On physical exam, his abdomen is
distended and tympanitic, and he has diffuse
abdominal tenderness without guarding. He has a
midline abdominal scar and a right subcostal scar. He
has had multiple abdominal surgeries including an
open aortic aneurysm repair, a cholecystectomy, and a
right hemicolectomy for colon cancer.
Differential Diagnosis
The constellation of abdominal pain, nausea, vomiting, and
decreased flatus/bowel movements is nonspecific but may
represent a small bowel obstruction. A mechanical small
bowel obstruction results when there is blockage of the
lumen of the small bowel. Neurogenic causes of bowel
dilatation such as a paralytic ileus can cause distention due
to a lack of bowel motility. In this patient with a history of
multiple abdominal surgeries, a mechanical bowel
obstruction is a concern.
Adhesions from prior surgery are the most common
cause of a mechanical small bowel obstruction, accounting
for up to two-thirds of all bowel obstructions. Incarcerated
hernias and neoplasms are the next most common cause.
Crohn’s disease or inflammatory bowel disease can cause
a mechanical obstruction in disea sed segments of bowel.
Less common causes of a small bowel obstruction include
volvulus, b ezoar, gallstone ileus, or intussusception (Table
1).
TABLE 1. Causes of Small Bowel Obstruction
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Small bowel neoplasms can progressi vely occlude the
lumen or serve as a leading poi nt for intussusception.
Symptoms may be intermittent as the onset is slow, and
patients usually have chronic anemia. Extrinsic neoplasms
may entrap loops or cause external compression.
Comprehensive physical exam looking for a hernia is a
must—patients with i ncarcerated hernias can present with
small bowel obstruction and bowel compromise. Internal
hernias, which may not be apparent on physical
examination, can occur through the obturator foramen,
acquired adhesive defects or lateral to surgical defects
(e.g., parastomal hernias). Volvulus results from rotation of
bowel loops from a fixed point due to congenital anomalies
or acquired adhesions. Patie nts with volvulus will usually
have acute onset of symptoms and strangulation often
occurs rapi dly. Malrotation of the intestine is a cause of
volvulus in children but is very rare in adults. Other rare
causes of obstruction include foreign bodies (bezoar,
ingested), gallstone ileus (passage of large stone through
cholecystenteric fistula), and inflammatory bo wel di sease
(secondary to inflammation and fibrosis of small bowel
wall).
Workup
The patient undergoes further evaluation with laboratory
workup significant for a mild leukocytosis, hypokalemia and
hypochloremia. He has no evidence of acidosis on his
initial labs and his creatinine is normal. His acute
abdominal series shows air-fluid levels and dilated loops of
small bo wel with no evidence of free air. He undergoes
computed tomography (CT) scan of the abdomen and
pelvis showing large fluid filled stomach, d ilated loops of
small bowel with possible transition point in the pelvis. His
distal ileum and colon are decompressed (Figure 1).
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FIGURE 1 • Dilated small bowel is evident as is a collapsed colon. A
transition point was found to be in the pelvis.
When presented with this clinical scenario, several
things need to be considered.
1. Is this a mechanical small bowel obstruction or is this
an ileus?
2. If a mechanical bowel obstruction, is the blockage
partial or complete?
3. Is this a simple or strangulating obstruction?
Workup for small b owel obstruction to help answer these
questions should include a combination of radiographic
and laboratory investigations. Initially an acute abdominal
series should be performed to look for free air, dilated
small bowel or stomach, air-fluid levels in small bowel, and
presence or absence of air/fluid in colon. A CT scan i s
often performed as a second evaluation to look a t integrity
of small bowel, and assess for the presence or absence of
signs of bowel i schemia including pneumatosis, complete
obstruction with a transition point, presence of small bowel
volvulus, intussusception, hernias, or neoplasm.
Laboratory evaluation may reveal leukocytosis, anemia
if there is a bleeding mass or elevated hematocrit if the
patient is volume contracted. Electrolyte abnormalities may
be present because of gastric losses and creatinine may
be elevated if the patient is dehydrated. If there is
significant bowel compromise, the lactic acid may be
elevated.
An ileus can at times mimic a small bowel obstruction.
Conditions that may cause an i leus are listed in Table 2.
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An ileus tends to affect the entire gastrointestinal tract and
there should not be a transition point on CT scan. With an
ileus, the large bowel is usually dilated as well as the small
bowel.
TABLE 2. Causes of Lleus
Diagnosis and Treatment
In the patient from our scenario, a nasogastric tube (NGT)
is placed and 1 L of bilious material is immediately
drained. He has partial resolution of his abdominal pain
following placement. Conservative treatment is elected and
he is placed on intravenous fluids and kept NPO.
Typically, if the patient is thought to have a partial small
bowel obstruction secondary to adhesions, a trial of
conservative (nonsurgical) management is pursued initially.
This includes NGT decompression, bowel rest, intravenous
fluid resuscitation, and correction of electrolyte
abnormalities. If the patient fails to improve clinically over
48 hours, it is likely that the patient requires an operation.
The challenge with treating a small bowel obstruction is
deciding when to operate. Sixty-five to ei ghty-five percent
of p artial small bowel obs tructions will resolve with
conservative management. The old dictum of “never let the
sun ri se nor set on a bowel obstruction” is still true for
complete small bowel obstruction, large bowel obstruction,
or when there is concern of strangulation or bowel
compromise. Delay in surgical therapy in these cases can
lead to irreversible bowel ischemia. However, proceed ing
with immedia te operation in patients with a pa rtial small
bowel obstruction may lead to an unnecessary intervention.
Indications for immediate operation include peritonitis,
sepsis, hemodynamic instability, acidosi s, or radiographic
evidence of small bowel compromise, such as
pneumatosis, perforation, signs of bowel ischemia, internal
hernia, or volvulus. Physical findings suggesting the need
for early operation are fever, tachycardia, and pain out of
proportion to physical findings. CT scanning provides
additional useful information. Although the presence of a
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transition point on CT scan has failed to reliably predict the
need for operation, there are some findings that should
alert the surgeon that e arlier surgery is warranted. B owel
compromise is associated with intraperitoneal fluid and
decrea sed enhancement of the bowel wall. Pneumatosis
and portal venous air can also be see n with bowel
ischemia. The presence of a “whirl sign” is concerning for a
volvulus or internal hernia (Figure 2).
FIGURE 2 • In the center of this CT scan image, there are mesenteric
vessels that move in a circular pattern to the left. This is known as a “swirl
sign” and is concerning for a potential volvulus. At operation, a loop of
bowel twisted around an internal hernia was found. Untwisting of the
mesentery restored blood flow and relieved the obstruction.
One special case worth mentioning i s postbariatric
surgery patients presenting with bowel obstruction.
Because of the mesenteric defects from the
gastrojejunostomy (often antecolic) and the
jejunojejunostomy, bariatric surgery patients are at very
high risk for internal hernias. If a large amount of small
bowel is involved, these patients can have catastrophic
midgut volvulus, even leading to short gut syndrome. In
these patients, the surgeon should look ca refully for
evidence of internal hernia or volvulus (e.g., mesenteric
“swirl” sign on CT scan) and promptly explore patients with
any suggestion of an internal hernia.
Small bowel obstruction due to intussusception in adults
is often due to a tumor of the small bowel that serves as a
lead point. The hallmark of i ntussusception on CT scan is
the presence of a “target si gn.” A target sign on CT scan
may at times be seen with normal peristalsis. However,
when evidence of intussusceptions on CT scan is
associated with a bowel obstruction or a mass (Figure 3),
operative i ntervention and small bowel resection with
removal of the abnormal segment are indicated.
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FIGURE 3 • Small bowel intussusception is demonstrated here with a
mass as the lead point. A spindle cell tumor was found at operation
causing the intussusception and bowel obstruction.
Surgical Approach
The usual approach to patients with bowel obstruction i s
through a midline incision (Table 3). Entering the abdomen
away from a prior incision may be beneficial if possible
(e.g., entering the midline just above or below a prior
laparotomy site). The abdomen is entered carefully with
sharp dissection in order to avoid bowel injury. The bowel
is freed from the anterior abdominal wall and is carefully
inspected. All a dhesions that could possi bly cause
obstruction a re taken down and the small bowel is
inspected in its entirety. It is i mportant to try and identify the
point of obstruction, or “transition point” where the bowel
goes from di lated to decompressed. It is much more
satisfying when the causative a dhesions are lysed.
However, oftentimes the transition point will not be obvious.
For very dense adhesions, dissection with a scalpel is
often useful. A ny areas of enterotomy can be repaired if the
bowel is viable. If it is not viable o r the damage is
extensive, a small bowel resection must be performed. In
order to determine viability you must assess the vascular
supply of the small bowel. This can be done by standard
clinical judgment (i.e., color and appea rance), D oppler
ultrasound of mesentery, and, in rare cases, fluorescein dye
evaluation.
TABLE 3. Key Technical Steps and Potential Pitfalls
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The less common causes of small bo wel ob struction
are usually apparent on inspection of the small bowel.
When the small bowel is inspected, any volvulus will be
reduced. Intussusception can be reduced by gentle traction,
and any masses/neoplasms can be resected. With all
circumstances, bowel viability must be assessed. Hernias
can be approached through an incision over the hernia
(umbilical, inguinal) with low threshold for conversion to
open laparotomy if there is concern for bowel strangulation
to assess intra-abdominal bowel. For hernias where
incarcerated and strangulated bowel is suspected, one
should not attempt reduction of the hernia until ope rative
intervention to allow inspection of the involved loop of
bowel.
During the operation, it is essential to be aware of a ny
enterotomies a nd spillage from small bo wel. Missed
enterotomies and spillage can lead to postoperative intraabdominal abscess, sepsis, and other morbidities.
Special Intraoperative Considerations
During exploration for small bowel resection, it is important
to be aware of findings of Crohn’s di sease. Findings of
Crohn’s d isease at laparotomy include fibrotic strictures,
usually short and multiple with “skip” areas of normal
interposed bowel. There is often “creeping fat” onto the
small bo wel. Strictures from Crohn’s disease can cause
obstruction and abdominal pain and often are managed
with strictureplasty rather than resection to avoid excessive
loss of small bowel and the development of short bowel
syndrome.
If an obstructing stone is found in the ileum just proximal
to the ileocecal valve, a “gallstone ileus” is likely the cause.
Inspection of the gallbladder is warranted to investigate the
possibility of a cholecystoenteric fistula. Often this is
diagnosed preoperatively due to the presence of air in the
bile ducts without any history of iatrogenic or surgical
intervention. Inspection of the entire small bowel for multiple
stones should be performed as there can be more than one
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stone present. Relieving the obstruction by performing an
enterotomy with removal of the stone is all that is usually
required for treatment. Repair of the cholecystoenteric
fistula is usually not necessary but can be considered in a
low-risk patient.
Postoperative Management
Postoperatively, the NGT should be continued until there is
return of bowel function with flatus. Care should be taken to
maintain the patient’s volume status and all electrolyte
abnormalities should be aggressively corrected. If the
patient has been in a fasted state for a long period of time,
consideration should be g iven to starting parenteral
nutrition. Patients with chronic obstructive problems may
have prolonged ileus following lysis of a dhesions.
Nutritional status is important to prevent complications
including wound infection and dehiscence.
Case Conclusion
Two days after admission, our patient still has output
from his NGT of 600 mL per shift and he has not
passed any flatus. He is taken to surgery where he is
found to have dense adhesions with a transition point in
postoperatively he has an uneventful course.
TAKE HOME POINTS
Complete bowel o bstructions or when bowel
ischemia is suspected requires early surgical
intervention
Partial bowel obstructions can be initially
conservatively managed with NGT decompression,
intravenous fluids, and close observation.
CT scanning can be helpful in distinguishing between
ileus and obstruction (i.e., determining the presence
of a “transition point” and identifying complications
that require immediate operative intervention, e.g.,
internal hernia, volvulus, or ischemic bowel).
Careful inspection for potential enterotomy will help
avoid the serious complication of postoperative small
bowel fistula.
Evaluation of the bowel’s blood supply i s i mportant.
Resect if ischemic, or if in doubt, consider a “second
look” operation.
Preserve as much small bowel as possible and if
significant amount of small bowel needs to be
resected, measure the amount of remaining small
bowel.
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SUGGESTED READINGS
Colon MJ, Telem DA, Wong D, et al. The relevance of transition zones on
computed tomography in the management of small bowel obstruction.
Surgery. 2010;147(3):373–377.
Diaz JJ Jr, Bokhari F, Mowery NT, et al. Guidelines for management of
small bowel obstruction. J Trauma. 2008;64(6):1651–1664.
Kendrick ML. Partial small bowel obstruction: clinical issues and recent
technical advances. Abdom Imaging. 2009; 34:329–334.
O’Day BJ, Ridgway PF, Keenan N, et al. Detected peritoneal fluid in small
bowel obstruction is associated with the need for surgical intervention.
Can J Surg. 2009;52(3):201–206.
Olasky J, Moazzez A, Barrera K, et al. In the era of routine use of CT scan for
acute abdominal pain, s hould all adults with small bowel
intussusceptions undergo surgery? Am Surg. 2009;75(10):958–961.
Zielinski MD, Eiken PW, Bannon MP, et al. Small bowel obstruction-who
needs an operation? A multivariate prediction model. World J Surg.
2010;34(5):910–929.
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