Intestinal obstruction is a blockage in the small or large intestine, categorized as mechanical or paralytic, with significant implications including acute and chronic forms. Diagnosis is often based on clinical signs such as abdominal pain, distension, and vomiting, confirmed through imaging studies. Treatment focuses on relieving the obstruction quickly, utilizing both conservative and surgical approaches depending on the severity and underlying causes.

1. Intestinal obstruction,
volvulus & Ileus
By: Khaled Alkhodari, MD

2. Definition
• Partial or complete blockage of the lumen of the small or large
intestine or via systemic alterations, involving both the small
and large intestine (generalized ileus) causing an interruption in
the normal flow of intestinal contents along the intestinal tract
• The block may or may not compromise the vascular supply

3. Classification

4. Classification
Sites : Small bowel / Large bowel
Duration :
Acute
/Chronic
Extent :
partial
/complete
etiopathogenesis
mechanical
/ paralytic
Ileus
Type:
Simple
strangulation
closed-loop
(complicated
obstruction(

5. Mechanical Small bowel
obstruction
Obstruction is the most
common surgical disorder
of the small intestine
Etiology:
Intraluminal
Extraluminal
Intramural

6. Causes?

7. Extrinsic causes

8. Intrinsic

9. Intraluminal

10. Mechanical Large bowel Obst
Aetiology
tumor 65%,Usually Lt sided tumors
18% of colonic ca. Present with obstruction
Diverticular disease 20%
Volvulus 5%
Others 10%

11. Chronic, partial obstruction
• Chronic small bowel obstruction occurs in a fixed segment of bowel,
and the obstruction is, by definition, partial. The most common
causes are chronic stricture from Crohn disease, adhesions from prior
surgery, slowly growing tumors, and stricture related to prior bowel
resection or irradiation.
• Patients usually present with chronic postprandial abdominal
discomfort and variable nausea. Abdominal distention and tympany
may be present, but usually without any fluid or electrolyte
derangements.
• When a patient with chronic, partial small bowel obstruction
becomes completely obstructed, the clinical presentation becomes
indistinguishable from acute obstruction as described above.

12. Recurrent obstruction
• Recurrent obstruction due to adhesions can occur in a fixed segment
of bowel or differing segments of bowel. Those that occur at the
same site due to a focal band adhesion are more likely to respond to
surgery compared with those that occur at varying locations within
the abdomen due to diffuse adhesions, for which surgery is likely to
increase the risk of future obstructions.
• During an episode of obstruction, symptoms are identical to those of
patients with acute small bowel obstruction described above, but
symptoms resolve and the patient may report post-obstructive
diarrhea. In the period between obstructive episodes, the patient is
usually asymptomatic with a normal abdominal exam.

13. Recurrent obstruction
• For patients with a history of prior bowel obstruction, whether
managed medically or surgically, the likelihood of recurrent
obstruction increases with an increasing number of episodes, and the
asymptomatic time period between episodes decreases.
• After three prior episodes, the likelihood of recurrent obstruction is
>80 percent

14. Acute Bowel obstruction

15. Pathophysiology

16. Pathophysiology
1. Increased intraluminal pressure by fluid & gas
2. sequestration of fluid into the lumen from the surrounding
circulation
3. Lymphatic and venous congestion ► in oedematous tissues
4. Further:impaired arterial microcirculation of intestine ►
localised anoxia, mucosal depletion necrosis , perforation &
peritonitis.
5. Bacterial over growth with translocation of bacteria and it’s
toxins ► bacteraemia and septicaemia. toxaemia

17. loss of fluid and electrolytes
in intestinal obstruction
• into the bowel lumen
• into the edematous bowel wall
• into the peritoneum
• vomiting or NG suction

18. hypovolemia ,oliguria & electrolytes imbalance.
restricted ventilation & atelectasis
Decreased venous return to the heart
septicaemia

19. Diagnosis
• The diagnosis suspected clinically based on the presence of
classic signs and symptoms and then confirmed by imaging
studies.
• The etiology can often be pinpointed by careful history-taking
complemented with imaging studies.

20. 4 cardinal features
I. colicky abdominal pain
II. distension
III. nausea and vomiting
IV. Obstipation
Usually the abdominal pain and then distention precede the
appearance of nausea and vomiting by several hours.

21. Abdominal pain
• Abdominal pain associated with small bowel obstruction is frequently
described as periumbilical and cramping with paroxysms of pain
occurring every four or five minutes.
• A progression from cramping to more focal and constant pain may
indicate peritoneal irritation related to complications (ischemia,
bowel necrosis).
• A sudden onset of severe pain may suggest acute intestinal
perforation.
• With proximal small bowel obstruction (duodenum, proximal
jejunum), nausea and vomiting can be relatively severe, and patients
with proximal small bowel obstruction typically cease taking in food
or liquids orally.

22. Abdominal pain
• usually described as visceral, poorly localized, and crampy with
recurrent episodes
with mechanical small bowel obstruction, the pain usually last
(4-5minutes)
in mechanical large bowel obstruction last longer (minutes
rather than seconds)
In strangulated obstruction
the pain is localized and persistent .

23. Nausea and vomiting
Vomiting Frequency & nature of vomitus depends on the level
of obstruction.
• High Small Bowel Obstruction Bile-Stained vomitus
• Lower Small Bowel Obstruction Feculent Vomitus
• Large Bowel Obstruction Uncommon & late symptom.

24. Abdominal distension
 more prominent in distal I.O. and may be absent in upper SBO.
Central in SBO . More in the flanks in colonic obstruction

25. Obstipation
• Early in “lower” Large Bowel Obstruction.
• Late in “High” Small Bowel Obstruction.
• H/O diarrhoea that is secondary to increased peristalsis

26. Understanding the clinical
findings
Colonic
•? Preexisting change
in bowel habit
•Colicky in the lower
abdomin
•Vomiting is late
•Distension prominent
•Cecum ? distended
Distal small bowel
•Pain: central and
colicky
•Vomitus is feculunt
•Distension is severe
•Visible peristalsis
•May continue to pass
flatus and feacus
before absolute
constipation
High small bowel
•Pain is rapid
•Vomiting copious and
contains bile jejunal
content
•Abdominal distension
is limited or localized
•Rapid dehydration
The Universal Features
Colicky abdominal pain, vomiting, constipation (absolute), abdominal
distension.

27. Physical examination
assessment of vital signs and hydration status,
• Pyrexia may suggests strangulation, infectious cause (intestinal
perforation)
• Hypothermia indicates septicaemic shock.
abdominal inspection, auscultation, palpation,
• succussion splash usually present In both mechanical and functional
bowel obstruction

28. Physical examination Inspection
• Surgical Scars ,
• Hernias,
• Distention,
• Visible Peristalsis

29. Physical examination Palpation
• diffuse, localized tenderness. rebound,and guarding suggest peritonitis
and strangulation
• Masses, abdominal mass may suggest closed loop obst.
• Hernias ,
• Perform Rectal Exam.

30. Physical examination
Percussion :
• Percuss to hear any Dullness or Resonance related to site of
obstruction.
Auscultation:
• Initially Hyperactive and frequent BS ( tinkles and Rushes ) →
Then as bowel distends the sounds become more resonant (No
sounds audible in late cases)

31. nondiagnostic, Assess dehydration
C.B.C.
Mild leucocytosis,
WBC 15,000- 25,000 suggestive for strangulation but not
sensitive .normal WBC does not exclude strangulation
Very high WBC 40,000-60,000 suggest primary
mesenteric vascular occlusion

32. Laboratory investigation
Electrolyte
BUN& creatinin, K, Na,
serum lactate concentrations, amylase & LDH are useful (but
not sensitive) tests in the evaluation of bowel obstruction,
suggest bowel necrosis.
A.B.G. metabolic acidosis or
hypochloremic hypokalemic metabolic
alkalosis by recurrent vomiting

33. Is there strangulation?
fever, tachycardia, localized tenderness
continuous pain, leucocytosis and
peritonitis
The presence of any three of the above signs
—has an 82% predictive value for strangulation
the presence of any four of the above signs has
a near 100% predictive value for strangulation
It is difficult to distinguish clinically between simple obstruction &
strangulation but there are features which suggests strangulation:

34. Radiological Examination
Always request: Supine, Erect and CXR
• Initial diagnostic study
• diagnostic of bowel obstruction in 50-80% of the cases,
Specificity is low because ileus and colonic obstruction can be associated
with finding similar to SB obst.
False negative finding
• in proximal SB obstruction and
• Closed-loop obstruction and
• When the bowel becomes markedly dilated, it may be impossible to
differentiate large from small bowel.

35. Plain radiography
• For most patients, we suggest plain radiographs to quickly confirm a
diagnosis of bowel obstruction because it is:
• widely available,
• inexpensive,
• and may demonstrate findings that indicate the immediate need for urgent
decompression (eg, sigmoid volvulus) or surgical intervention (eg,
pneumoperitoneum, cecal or midgut volvulus).
• Plain radiography also assesses the lungs for evidence of aspiration in those
who have been vomiting and can easily be repeated to follow the patient's
progress.

36. • The basic radiologic examination should include:
• an upright chest film and
• upright and supine abdominal films.
• If the patient cannot be placed into an upright position, a
lateral decubitus abdominal film can show free air and/or air-
fluid levels.

37. Radiological Examination
Radiological features in large bowel obstruction
• Colonic distension usually visualized in the periphery
• show the hustrations of the Taenia Coli.
• absence of rectal air and air fluid level if ileocecal valve incompetent
• May also demonstrate the cause of obstruction (volvulus)

38. The Difference between small and large
bowel obstruction
Small BowelLarge bowel
•Central ( diameter > 3 cm )
•Vulvulae coniventae
•Ileum: may appear tubeless
•Peripheral ( diameter >5- 9 cm )
•Presence of haustration

39. • Mechanical obstruction: The bowel proximal to the obstruction is
dilated. Therefore, the more distal the obstruction, the more loops of
bowel are visible.
• Mechanical obstruction and ileus appear identical, and in most cases
the underlying cause cannot be determined on an abdominal X‐ray

40. Radiological signs to look for in SB & LB:

43. Radiological signs to look for:
• Dilation >3 cm: The small bowel is dilated if it measures over 3 cm in
diameter.
• Central location: The dilated loops are more likely to be centrally
located on the abdominal radiograph.
• Valvulae conniventes: These are the mucosal folds of the small
intestine. They are thin, closely spaced and classically seen as a
continuous thin line across the entire width of the bowel.
• Air fluid level in upright position

61. Who wants to be a hero ?

62. Pick up 3 findings

65. Who wants to be a hero ?

68. Radiological Examination
Contrast Studies:
prograde enteroclysis or retrograde
• recommended in patients with a history of recurrent obstruction or a
nonresolving partial SBO
• differentiate between partial & complete obstruction
• can demonstrate the site, degree and often the cause of obstruction.
• A retrograde contrast study useful in the patient with suspected large
bowel obstruction

69. Radiological Examination
Contrast Studies:
• The contrast agent of choice controversial .
• dilute barium ??,
• water-soluble contrast??
• The use of both types of contrast agent has risks
contraindicated in patients with a clear diagnosis of complete
bowel obstruction and when strangulation or perforation is
suspected

70. Radiological Examination
Contrast Studies:

71. Differentiate mechanical from pseudoobstruction
Define level and type of obstruction
volvulus bird beak appearance
Rectal cancer apple- core appearance

72. .
• Specificity and sensitivity > 90% for complete obstruction Less for
partial
• Used with iv contrast, oral and rectal contrast (triple contrast).
• demonstrate abnormality in the bowel wall, mesentery, mesenteric
vessels and peritoneum.
• CT has replaced the typical small bowel contrast studies in many
centers.
• Indicated especially when abdominal films are nonspecific or
when strangulation is suspected

73. advantage of CT
• imaging of structures other than just mucosal detail,
• visualize all intra-abdominal compartment as well as defects in
the abdominal wall.
• the ability to visualize closed loop obstruction presence of U or
C shaped dilated bowel
• the ability to visualize strangulation & ischaemia
• It can define Free fluid and gas
• Partial / complete

74. some have argued that because abdominal CT is more effective for
identifying patients who will need intervention, abdominal CT should
be performed initially instead of plain films. However, we generally
obtain plain abdominal films (flat and upright/left lateral decubitus)
prior to proceeding to abdominal CT scan, since radiographs are readily
available, less expensive, expose the patient to less radiation, and may
obviate the need for abdominal CT in some patients

75. Radiological Examination
USG - useful in pregnant patients
• Shows ( free fluid, masses, mucosal folds, solid organs, pattern
of paristalsis, Doppler of mesenteric vasulature,)
• more sensitive and specific than plain abdominal films for the
diagnosis of bowel obstruction but less accurate than CT.
• US is very much operator-dependent
MRI - no better diagnostically than CT.

76. • have diagnostic and therapeutic roles in decompression of
volvulus and pseudoobstruction

77. Treatment
• Aim of Rx: is to relieve obstruction as soon as possible before
strangulation occurs or before systemic complications set in.

78. Supportive Treatment
Nil per os
fluid resuscitation most important initial step
sometimes with central venous assessment
Nasogastric aspiration
urine output monitoring.
broad spectrum antibiotic
TO OPERATE OR NOT TO OPERATE

79. Conservative treatment
• Partial obstruction ( progression to strangulation unlikely)
• Obstruction secondary to Crohn’s disease often respond to
medical therapy
• Recurrent obstruction
• abdominal carcinomatosis
• previous abdominal radiation
• Pat. With previously massive small bowel resection

80. The timing of conversion to
operative management
• more controversial.
• No improvement within 48 hours of initiating therapy.
• Others advocate longer than 48 hours

81. When to Convert to Operative
Management
• If a patient being treated nonoperatively develops evidence of a
complicated obstruction,
• Patients who develop free air or signs of a closed-loop
obstruction
• If evidence of ischemia, strangulation, or vascular compromise
is noted on CT,

82. Contraindications to
non operative management
• suspected ischemia,
• large bowel obstruction,
• closed-loop obstruction,
• strangulated hernia,
• perforation.
A relative contraindication
• complete small bowel obstruction.

83. Operative Treatment
Laparoscopic management
criteria for laparoscopic surgery include those
with the following symptoms:
• Mild abdominal distension allowing adequate visualization
• Proximal obstruction
• Partial obstruction
• Anticipated single-band obstruction

84. • Virtually all patients with complete acute large bowel obstruction
require prompt surgical intervention and should not undergo
a trial of nonoperative management because of the high risk of
perforation.
• Treatment according to the cause
• The role of laparoscopic exploration for large bowel obstruction
is much less well defined

91. Sigmoid volvulus, Management
• The goal of treatment of sigmoid volvulus is to reduce the sigmoid volvulus
and to prevent recurrent episodes.
• We perform a flexible sigmoidoscopy to reduce a sigmoid volvulus and then
perform definitive surgery to prevent recurrent volvulus.
• We perform immediate laparotomy when endoscopic detorsion is unsuccessful
or in patients with signs and symptoms suggestive of peritonitis.
• However, the management of sigmoid volvulus is controversial. Some experts
recommend that endoscopy be reserved for patients who are not candidates
for definitive surgical therapy, while others recommend surgery be reserved for
patients in whom sigmoidoscopic reduction is unsuccessful since approximately
40 to 50 percent of patients with sigmoid volvulus will not have a recurrence.

92. • Endoscopy — A sigmoidoscope can detorse the sigmoid volvulus when
advanced through the twisted segment of the colon, thereby restoring the
blood supply. An additional advantage of sigmoidoscopy is that it allows for
an assessment of the viability of the colon. Endoscopic reduction of a
sigmoid volvulus has been reported to be successful in 75 to 95 percent of
cases.
• Initial sigmoidoscopic reduction of the volvulus converts an emergency
procedure into a semiurgent procedure, performed 24 to 72 hours after
endoscopic reduction of the volvulus, such that bowel preparation
(cleanout) can be accomplished. Although surgical resection without
decompression has been used at some centers with acceptable outcomes,
we favor preoperative decompression whenever feasible.

93. PROGNOSIS
• The mortality related to sigmoid volvulus is highest in patients who
have developed gangrene and ranges from 11 to 60 percent in case
series.
• In contrast, the mortality is less than 10 percent in patients who have
not developed gangrene.
• Recurrence of an initial episode of sigmoid volvulus that is not
treated with surgery occurs in up to 60 percent of patients.
• The recurrence rate after a second episode is probably even higher,
and therefore surgery is almost always recommended after repeated
episodes of sigmoid volvulus. The time to recurrence can vary from
hours to weeks or months.

99. Cecal volvolus
• CT scan — In patients with axial torsion of the cecum (type I or II), a
computed tomography (CT) finding of the "whirl sign" (twisting of the
mesentery around the ileocolic vessels) is pathognomonic for cecal
volvulus. In addition, CT scan may also demonstrate signs of bowel
obstruction (a massively dilated cecum with associated small bowel
dilation) (image 5) or signs of colonic or small bowel ischemia (mural
thickening or mesenteric edema) [9]. In patients with a cecal bascule (type
III), CT scan shows the cecum folding upward, resulting in obstruction
without the axial twist of the mesentery (image 6).
• Contrast studies — A single-contrast barium or Hypaque enema
demonstrates a tapered or "bird's-beak" narrowing in the right colon,
confirming a cecal volvulus (image 7).

103. MANAGEMENT
• The management for patients with a cecal volvulus is primarily
surgical. Nonoperative reduction of cecal volvulus (eg, by
colonoscopy or barium enema) is rarely successful (<5 percent) and
could cause perforation; it therefore should not be attempted.
• In addition, colonic necrosis may be missed in 20 to 25 percent of
patients who undergo nonoperative reduction, and such patients may
develop colonic perforation [2,14,30-32].
• Surgical approaches to cecal volvulus vary depending upon
intraoperative findings and patient stability

107. Definition
• Impaired intestinal motility due to paralysis of intestinal
musculature that prevents coordinated transit of luminal
contents

108. Ileus can be classified as
Ileus
Functional
"physiologic“
Postoperative ileus
adynamic
"paralytic" ileus
Colonic
pseudoobstruction

109. Postoperative ileus
• An international consensus panel proposed that "normal" or
"obligatory" postoperative ileus be defined as the period of time,
lasting fewer than four days, from surgery until the passage of flatus
or stool and tolerance of an oral diet.
• The same panel defined "prolonged" postoperative ileus as the
occurrence of two or more of the following signs and symptoms on
postoperative day 4 or after [23]:
• ●Nausea or vomiting
• ●Inability to tolerate an oral diet over the preceding 24 hours
• ●Absence of flatus over the preceding 24 hours
• ●Abdominal distention
• ●Radiologic confirmation

110. • Following abdominal surgery, "normal" physiologic
postoperative ileus due to postoperative gut dysmotility is
widely reported as lasting:
• 0 to 24 hours in the small intestine,
• 24 to 48 hours in the stomach,
• and 48 to 72 hours in the colon

111. Definitions of "prolonged" postoperative ileus
have included:
• No return of bowel function postoperatively (ranging from postoperative
days 4 to 6)
• Absence of flatus or stool on postoperative day 6
• Postoperative nausea or vomiting requiring cessation of oral intake,
intravenous support, or nasogastric tube placement by postoperative day 5
• Return of bowel function after postoperative day 5
• Absence of flatus and/or bowel movement prolonging hospitalization
beyond discharge goal (ranging from postoperative days 6 to 8)
• Lack of bowel activity more than five days after surgery

112. Measures to
prevent
prolonged post
op ileus

113. Paralytic ileus
(Adynamic ileus )
• can take days or even weeks to resolve.
• usually is secondary to or caused by different pathophysiologic
mechanisms

114. Causes of Adynamic ileus
• Metabolic Causes Hypokalemia. Hypomagnesemia. Hyponatremia.
Ketoacidosis. Uremia, hypothyroidism
• Medications Narcotics. Antidepressant, Anticholinergics. Ca-channel
blockers
• Retroperitoneal irritation hematoma. Pancreatitis. infection ,ureteric
stones, Spinal or pelvic fracture.
• peritoneal irritation Infection, sepsis, intraabdominal abscess, peritonitis
• Thoracic conditions e.g. pneumonia, # ribs

115. • Abdominal distension
• minimal or Without abdominal pain
• +/- Nausea, vomiting
• +/- Flatus, diarrhea

116. decreased or absent bowel sounds.
Plain abdominal radiography
distended gas-filled loops of
small and large intestine.
Air-fluid levels may be seen

117.  Under some circumstances, it may be difficult to distinguish ileus from partial
small bowel obstruction. ►
CT scan may be useful to
exclude mechanical
obstruction, especially
in postoperative patients.

119. Treatment
Fluid , NGT, Correct electrolyte abnormalities
Most importantly, the underlying cause of ileus needs to be
addressed
• Aggressive treatment of sepsis, and associated intra-abdominal
processes
Check medicines
Block sympathetic& stimulate parasympathetic (parenteral
neostigmine)
meteclopramide & I.V.erythromycin
Cispraide out of mark due to cardiac toxicity

120. • Acute colonic pseudo-obstruction (Ogilvie's syndrome) is a
disorder characterized by acute dilatation of the colon in the
absence of an anatomic lesion that obstructs the flow of
intestinal contents.
• Pseudo-obstruction is characterized by signs and symptoms of a
mechanical obstruction of the small or large bowel in the absence of
a mechanical cause. Pseudo-obstruction may be acute or chronic and
is characterized by the presence of dilation of the bowel on imaging

122. Presentation
• Abdominal distension usually occurs gradually over three to seven
days but may develop rapidly within 24 to 48 hours.
• Approximately 80 percent of patients have associated abdominal
pain.
• Nausea and vomiting may be seen in up to 60 percent of patients.
• Constipation and, paradoxically, diarrhea have also been reported in
approximately 50 and 40 percent of patients, respectively

123. • On physical examination,
• the abdomen is tympanitic,
• but bowel sounds are present in almost 90 percent of patients.
• However, the presence of fever, marked abdominal tenderness, and
the presence of peritoneal signs (eg, guarding, rigidity, rebound
tenderness) are suggestive of colonic ischemia or perforation or their
impending development

124. DIAGNOSIS
• The diagnosis of acute intestinal pseudo-obstruction should be
suspected in patients with abdominal distension or pain and a
physical examination that reveals a distended and tympanitic
abdomen.
• The diagnosis of acute intestinal pseudo-obstruction is established by
abdominal imaging.
• Colonoscopy should not be used to make the diagnosis of acute
intestinal pseudo-obstruction, as insufflation of air may increase the
colonic dilatation.

126. Management
• Initial management of acute colonic pseudo-obstruction is usually
conservative in patients without
• significant abdominal pain,
• extreme (>12 cm) colonic distension,
• or signs of peritonitis
• and those who have one or more potential factors that are reversible

128. Management

129. • In patients with cecal diameter >12 cm and in patients who have
failed 24 to 48 hours of conservative therapy, we use pharmacologic
therapy with neostigmine.
• In patients who fail or who have contraindications to neostigmine, we
perform colonoscopic decompression
• Percutaneous colostomy should be reserved for patients who fail
endoscopic decompression and are not surgical candidates.
• We reserve surgical decompression for patients who fail endoscopic
and pharmacologic therapy or have evidence of perforation or
peritonitis

130. Thank you