Bowel obstruction, also known as intestinal obstruction, is a mechanical or functional obstruction of the intestines which prevents the normal movement of the products of digestion. Either the small bowel or large bowel may be affected. Signs and symptoms include abdominal pain, vomiting, bloating and not passing gas.

1. INTESTINAL
OBSTRUCTION
SHAHRUKH SULTAN AHMED
Kyiv Medical University
Department of Surgery

2. DEFINITION
Interruption of
normal passage
of intestinal
contents.

3. CLASSIFICATION
DYNAMIC : where peristalsis is working against a mechanical obstruction.
ADYNAMIC: it may occur in two forms
1. 1st where peristalsis may be absent (paralytic ileus,)occurring secondarily to
neuromuscular failure in the mesentery.
2. 2nd where peristalsis may be present in nonpropulsive form.(pseudo-obstruction)
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4. CAUSES
 Dynamic:
1.Intraluminal: Impaction, Foreign body
Bezoars, Gallstones
2.Intramural : Stricture, Malignancy
3. Extramural: Bands/adhesions, Hernia,
Volvulus ,Intussusception
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 Adynamic
• Paralytic ileus,
Mesenteric vascular
occlusion,
Pseudo-obstruction

5. ONTHE BASIS OF NATURE IT IS
CLASSIFIED INTO
ACUTE
CHRONIC
ACUTE ON CHRONIC
SUBACUTE

6. ACUTE OBSTRUCTION :
IT USUALLY OCCUR IN SMALL BOWEL OBSTRUCTION WITH
SUDDEN ONSET OF SEVERE COLICKY CENTRAL ABDOMINAL PAIN,
DISTENTION AND EARLYVOMITING AND CONSTIPATION.

7. CHRONIC OBSTRUCTION :
USUALLY SEEN IN LARGE BOWEL OBSTRUCTION WITH LOWER
ABDOMINAL COLIC AND ABSOLUTE CONSTIPATION,FOLLOWED BY
DISTENTION

8. ACUTE ON CHRONIC OBSTRUCTION :
IT STARTS IN LARGE BOWEL BUT GRADUALLY INVOLVES THE SMALL
INTESTINE.
EARLY SYMPTOMS ARE PAIN AND CONSTIPATION BUTWHEN SMALL
INTESTINE IS INVOLVED IT IS CHARACTERIZED BYVOMITING AND
GENERAL DISTENTION.

11. COMMON CAUSES OF MECHANICAL
SMALL BOWEL OBSTRUCTION:
1. Adhesions and bands following abdominal surgery
2. External hernia
3. Intussusceptions
4. Volvulus
5. Neoplasm (benign or malignant).
6. Obstruction : worms
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12. COMMON CAUSES OF MECHANICAL
LARGE BOWEL OBSTRUCTION
1
2
1. Large bowel cancer.
2. Sigmoid diverticular disease.
3. Sigmoid volvulus.

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14. 1
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15. 1
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16. COMMON CAUSES OF NON-MECHANICAL
SMALL-BOWEL OBSTRUCTION
1– Paralytic ileus after abdominal surgery
2– Localized intra abdominal abscess or generalized
peritonitis
3– Mesenteric embolism or thrombosis with small
bowel infarction
4– Intestinal pseudo-obstruction
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17. COMMON CAUSE OF NON-MECHANICAL
LARGE BOWEL OBSTRUCTION:
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1 – Retroperitoneal hematoma following lumber
fracture or lumber surgery
2 – Idiopathic

18. COMMON CAUSES SBO
60%20%
5% 5%
10%
Adhesions
Neoplasms
Hernias
Crohns
Miscellaneous

19. PATHOPHYSIOLOGY
 Dilation proximal to obstruction (gas & fluid)
Hyper-peristalsis Become Vigorous
Peristalsis Ceases Obstruction Not Relieved
Flaccid, Paralysed, Dilated Bowel
 Dehydration due to :
1. Reduced oral intake
2. Defective intestinal absorption
3. Vomiting
4. Sequestration in Bowel Lumen

20. MECHANICAL OBSTRUCTION:
Three main types:
1 -Simple
2 – Closed-loop
3 - Strangulation

21. 1 -SIMPLE OBSTRUCTION
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 The bowel is usually occluded at one
level.

22. 2 - CLOSED LOOP OBSTRUCTION
 Bowel obstructed at both proximal & distal
points
 There is rapid increase in the intra luminal
tension, Gangrene or perforation can occur
more quickly, peritonitis.
 Example: Colonic obstruction with
competent ileocaecal valve

23. 3 . STRANGULATION
 This is the end result a closed loop
obstruction when major arterial supply to the
affected bowel has been occluded , causing
gangrene over a considerable area.

24. MECHANICAL OBSTRUCTION
 Following questions must be answered:
1 – Is it obstruction and if so at what level ?
2 – Is strangulation present ?
3 – Is dehydration present ?
4 – What is the cause ?
5 - What is the treatment ?

25. 1 – IS IT OBSTRUCTION,AND IF SO,
ATWHAT LEVEL ?
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 The question is answered by considering the
clinical features.
Symptoms
Signs

26. SYMPTOMS
The cardinal features of
bowel obstruction are,
1. Pain
2. Vomiting
3. Constipation
4. Distension
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27. PAIN
 Sudden, severe
 Colicky in nature
 Central , around umbilicus in small bowel
obstruction
 Lower abdomen in large bowel obstruction
 Continuous if perforation or strangulation is present
 Absent in paralytic ileus.
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28. VOMITING
2
2
 Early in high small bowel obstruction,
 Late in low small bowel obstruction ,
 Delayed or absent in large bowel obstruction.
 Character : initially clear ,becomes discolored
, and finally feculent (dark and foul smiling).

29. CONSTIPATION
2
3
 Early in large bowel obstruction
 Absolute in complete obstruction

30. Local signs in the abdomen are:
 Inspection:
 Scar
 Distension, central in small bowel obstruction and peripheral
in large bowel obstruction
 Visible peristalsis
SIGNS
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31.  Palpation:
 Abdominal mass may suggest carcinoma or
strangulated bowel.
 Rigidity and rebound tenderness , indicates ischemia
& peritoneal irritation.
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32.  Percussion:
 Resonance because of gas filled bowel
 Tenderness on percussion indicates the presence of
peritonitis.
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33.  Auscultation:
 Bowel sounds
 Tympani
 Metallic clicks as pressure is raised if much gas is
present in the bowel.
 Gurgling borborygmi if gas and fluid are present in
the bowel.
 Silence if generalized peritonitis or paralytic ileus is
present.
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34.  On rectal examination:
 Impacted feces
 Rectal cancer
 Blood on finger which maybe present with mesenteric
artery occlusions, intussusception or Volvulus.
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35. 2 – IS STRANGULATION PRESENT ?
 Fever
 Tachycardia,
 Leukocytosis
 Constant pain
 Rebound Tenderness & rigidity
 Shock
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36. 3 – Is Dehydration present ?
 Tachycardia
 Hypotension
 Dry skin
 Dry mouth
 Poor skin turgor
 Small volume concentrated urine.
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37. 4 - WHAT ISTHE CAUSE?
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1 - Previous abdominal surgery and features of small
bowel obstructions suggest adhesions, The attacks may
have been recurrent
2 - Large bowel obstruction and history of constipation
with intermittent mucous or bloody diarrhea suggest
carcinoma of the colon
3 – No previous operations and symptoms of small bowel
obstruction suggest obstructed hernia or an
uncommon cause such as congenital band, internal
hernia or mesenteric occlusion.

38.  Laboratory Examination
1. Complete blood count (WBC)
2. Serum electrolytes and amylase determination
3. Arterial blood gas analysis
INVESTIGATIONS

39. INVESTIGATIONS
 Radiologic Examination
1. Sigmoidoscopy (Carcinoma, Sigmoid Volvulus,
Inflammatory stricture)
2. Plain X-ray of the abdomen, erect
3. Single- contrast water-soluble enema study
4. CT Scan

40. 3
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41. 5 – MANAGEMENT
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Non operative :
• In case of Simple obstruction without strangulation .
• Gastrointestinal decompression: NG tube
• IV fluid
• Antibiotics
 Operative:
• Usually surgery
• Replace fluid before surgery