3. 3
Definition
Blockage of the passage of intestinal contents
through the lumen of the bowel
Failure of intestinal contents to pass through
the bowel lumen
4. 4
Etiology
Mechanical intestinal obstruction
Also called dynamic obstruction
Peristalsis is working against a mechanical
obstruction
Functional intestinal obstruction
Also known as adynamic obstruction
May occur in two forms:-
Paralytic ileus
Absence of peristalsis
Pseudo-obstruction
Peristalsis is present in a non-propulsive form
5. 5
Mechanical / Dynamic
obstruction
Intraluminal causes
In the lumen
Intramural / Intrinsic causes
In the wall of the gut
Extramural / Extrinsic causes
Outside the wall
7. , differentiate these diseases.
crohn’s disease- regional enteritis, chronic
granulomatous inflammation of the bowel
esp terminal ileum with scarring and wall
thickening leading to IO, fistulae &
abscesses.
Celiac disease – a mal-absorption syndrome
ppted by ingestion of gluten containing
foods with loss of villous structure of
proximal intestinal mucosa, bulky froth
diarrhoea, abdominal distension flatulence,
wt loss, vit and electrolyte depletion
7
13. 13
Classifications
According to the cause of obstruction
According to the site of obstruction
According to the mode of onset of
obstruction
According to the nature of obstruction
According to the integrity of blood supply to
the bowel
According to severity
14. 14
According to the cause
Mechanical / dynamic obstruction
Functional / Adynamic obstruction
15. 15
According to the site of
obstruction
Small bowel obstruction
High [proximal bowel involving the duodenum
to mid jejunum]
Low [distal bowel from mid jejunum to ileum]
Colonic obstruction
16. 16
According to the mode of
onset
Acute intestinal obstruction
Chronic intestinal obstruction
Acute on chronic intestinal obstruction
Sub-acute intestinal obstruction
17. 17
Acute intestinal obstruction
Usually occurs in small bowel obstruction
Presents with sudden onset of severe colicy,
abdominal pain, distention, vomiting and
constipation
18. 18
Chronic intestinal obstruction
Usually seen in large bowel obstruction
Presents with gradual onset of lower
abdominal pain and absolute constipation,
followed by distention
19. 19
Acute on chronic intestinal
obstruction
This is acute exacerbation of a chronic obstruction
There is a short history of distention and vomiting
against a background of pain and constipation
21. 21
According to the nature of
obstruction
Open loop obstruction
Closed loop obstruction
22. 22
Open loop obstruction
Only the distal end of the bowel segment is blocked
Proximal end
Distal end
23. 23
Closed loop obstruction
This occurs when the bowel is obstructed at both
the proximal and distal end points e.g. intestinal
volulvus hernia
24. 24
According to the integrity of
blood supply to the bowel
Simple /non-strangulating bowel
obstruction
Strangulating / Strangulated bowel
obstruction
26. 26
Strangulating bowel
obstruction
In this type there is direct interference with
blood supply to the bowel
in strangulating obstruction, arterial and
venous flow of a bowel segment is cut off
28. 28
Partial / incomplete bowel
obstruction
Meaning that the lumen is narrowed but permits
distal passage of some fluid and air
Pt can pass flatus
E.g. Richter's hernia in which a strangulated
hernia involving only one sidewall of the bowel,
which can result in bowel perforation through
ischemia without causing bowel obstruction
29. 29
Complete bowel obstruction
In which there is complete mechanical
blockage of the normal progression of the
intestinal contents
Pt can not pass flatus
In this case the intestinal lumen is totally
occluded
E.g. sigmoid volvulus
30. 30
Pathophysiology
Stage I. Proximal dilatation and collapse of
the distal segment
Stage II: Increased secretory activity of the
gut mucosa
Stage III: Increased peristalsis to overcome
obstruction
Stage IV: Impaired blood supply bowel
ischemia
Stage V: Bacterial translocation peritonitis
or bacteremia
31. 31
Stage I. Proximal dilatation &
Collapse of the distal segment
This is due to accumulation of fluid and air
Sources of fluid is from GI secretions
Saliva
Gastric juices
Pancreatic juices
Sources of air
Swallowed air
From bacterial fermentation
From blood vessels
Accumulation of fluid and air ABDOMINAL
DISTENTION
Collapse of the distal segment SPORIOUS
32. 32
Stage II: Increased secretory
activity of the gut mucosa
Bowel dilatation stimulates cell secretory activity &
impair absorption
More fluid accumulation
Excessive bowel distention
Increased intraluminal pressure
33. 33
Stage III: Increased
peristalsis
Excessive Bowel distention intraluminal
pressure
Stimulation of stretch receptors in the wall of
the gut
d peristalsis both above and below the
obstruction with frequent loose stools and
flatus early in its course
Further rise in Intraluminal pressure
increased wall tension
34. 34
Stage IV: Impaired blood
supply bowel ischemia
Further increase in bowel distension &
intraluminal pressures
Compression of mucosal lymphatics
Bowel wall lymphedema & impaired venous
return
Capillary engorgement and loss of intravascular
fluid into bowel lumen, bowel wall and
surrounding tissues DEHYDRATION
Progressive bowel wall edema
Intestinal arterial supply occluded
35. 35
Stage V: Bacterial
translocation
Bacteria in the gut proliferate proximal to the
obstruction
Migration of aerobic and anaerobic bacteria across
intestine wall and/or intestinal perforation
peritonitis
Generalized peritonitis
CIRCULATORY COLLAPSE
38. 38
Abdominal pain
Pain is the first symptom
It occurs suddenly and usually severe and
colicky in nature
Site: periumbilically in small bowel obstruction
and lower in colonic obstruction
Often, the presentation may provide clues to
the approximate location and nature of the
obstruction
39. 39
Abdominal pain [cont’d]
Pain that occurs for a shorter duration of
time and is colicky and accompanied by
bilious vomiting may be more proximal
Pain lasting for several days, which is
progressive in nature and with abdominal
distention, may be typical of a more distal
obstruction
Changes in the character of the pain may
indicate the development of a more
serious complication [bowel ischemia]
40. 40
Vomiting
Vomiting occurs early and profuse if the
level of obstruction is proximal
It is delayed in case of distal obstruction
As obstruction progresses the
characteristics of vomitus alters from
digested food to faeculent material due to
presence of enteric bacterial overgrowth
41. 41
Abdominal distension
Proximal small bowel has less distension
when obstructed than the distal bowel has
when obstructed
The more distal the obtruction the greater
the degree of distention
42. 42
(infrequent or difficult in evacuation of
faeces)
Classified as absolute or relative
Absolute constipation meaning neither
faeces nor flatus is passed
Relative constipation means only flatus is
passed
Absolute constipation is a cardinal feature of
complete obstruction where relative
constipation is a feature of incomplete
obstruction
43. 43
Constipation [cont’d]
Exceptions:-
Partial obstruction
Obstruction associated with pelvic
abscess
Gall stone obstruction
Mesenteric vascular occlusion
Richter’s hernia
46. 46
Dehydration
This is seen most commonly in small
bowel obstruction due to repeated
vomiting and fluid sequestration
This result in dry skin and tongue, sunken
eyes and poor venous filling
48. 48
Pyrexia
Pyrexia in the presence of obstruction may
indicate:-
Onset of bowel ischaemia
Intestinal perforation
Inflammation associated with the
obstructing disease
Hypothermia indicates septicaemic shock
49. 49
Abdominal examination
Abdominal distension
Visible peristalsis
An old laparotomy scar
Tender mass at one of his hernial orifice
Abdominal tenderness
A palpable abdominal mass
Hyper-resonance
Hyperactive bowel sounds occur early as GI
contents attempt to overcome the obstruction.
Hypoactive bowel sounds occur late.
Rectal examination
55. 55
Abdominal radiographs
2 views are required
Supine
Erect
Dilated bowel loops with air-fluid levels
indicate IO
Able to show the level of obstruction
Unable to distinguish between simple and
strangulating IO
Small bowel lie centrally and colon
56. 56
Abdominal radiographs [cont]
Jejunal obstruction shows valvulae
conniventes i.e. parallel lines spanning the
entire width of the bowel lumen
Obstructed ileum appears cylindrical with
less clearly valvulae conniventes
Obstructed colon shows dilated bowel with
haustral markings
58. 58
Contrast studies
This is valuable in detecting presence of obstruction
and in differentiating partial from complete
blockages.
This study is useful when plain radiographic findings
are normal in the presence of clinical signs of IO or if
plain radiographic findings are nonspecific.
2 types of Contrast agents used in this study-water
insoluble CM eg barium or water soluble CM eg
Gastrografin
Barium is commonly used -It is safe and useful
when diagnosing obstructions provided no evidence
of bowel ischemia or perforation exists
60. 60
Abdominal ultra-sound
Ultrasonography is less costly and less
invasive
It may reliably exclude IO in as many as
89% of patients.
Specificity is reportedly 100%.
61. 61
CT scan- abdominal
It is useful in making an early diagnosis of
strangulated obstruction
Bowel wall thickening indicates early
strangulation.
Portal venous gas indicates early strangulation.
Pneumatosis indicates early strangulation.
It is also useful in distinguishing the etiologies of IO,
ie, extrinsic causes such as adhesions and hernia
from intrinsic causes such as neoplasms or Crohn
disease
It also differentiates the above from intraluminal
63. 63
Goals of treatment
Fluid and electrolyte replacement
Gastrointestinal drainage to alleviate
vomiting, abdominal distension and to
reduces the risk of aspiration pneumonia
Prophylaxic antibiotics to avoid bacterial
overgrowth
Relief of obstruction, usually surgical
64. 64
The principles of
management
Correction of fluid and electrolyte
imbalance
Nasogastric decompression
Nil per oral
Prophylactic antibiotics
Analgesics
Definitive treatment
65. 65
Correction of fluid and
electrolyte imbalance
Fluid and electrolyte replacement is
important to correct gastrointestinal tract
loss
A large bore canula should be inserted
immediately and fluid continued until daily
requirements of fluid and electrolytes is
achieved
The replacement is achieved by giving
initially crystalloids e.g. Hartman’s soln,
Ringers Lactate, Normal saline
66. 66
Nasogastric decompression
This is achieved by passing a NGT of
suitable size and aspirate it regularly
Make sure it reaches the patient’s stomach
and be sure it is draining properly
aims;:-
Stop vomiting
Reduce distension
Reduce the danger of aspiration during
anaesthesia
67. 67
Nil per oral
The patient should be restricted from
diet relief of obstruction
68. 68
Prophylactic antibiotics
Broad spectrum antibiotics should be
initiated early in therapy because of
bacterial overgrowth
Antibiotics therapy is mandatory for all
patients undergoing bowel resection
71. 71
Conservative treatment
Indications
Obstruction due to Ascaris worms
Obstruction due to adhesions
Obstruction due to paralytic ileus
Typhoid fever causing partial obstruction
Plastic tuberculosis peritonitis
A localized inflammatory mass e.g.
appendicular mass, pyosalpinx or PID
Pelvic abscess which can be drained
rectally or vaginally
72. 72
Conservative treatment cont..
Includes:-
Correction of fluid and electrolyte imbalance
Nasogastric decompression
Nil per oral
Prophylactic antibiotics
Analgesics
Other modalities include:-
Decompression of sigmoid volvulus with a
sigmoidoscope
Hydrostatic reduction of intussusception with
a contrast enema
73. 73
Surgical treatment
Indications
Timing of surgical intervention
Pre-operative care
Intra-operative care
Post-operative care
Follow up care
74. 74
Indications
Failure of conservative treatment
Presence of underlying disease
process that must be treated e.g.
hernia, obstructing tumor etc
Signs of peritoneal irritations
75. 75
Timing of surgical
intervention
The timing of surgical intervention is
dependent on the clinical picture with the
indications of early operation being:-
Obstructed or strangulated external hernias
Internal intestinal strangulation
Acute obstruction
Conservative treatment should not
continue beyond 72 hours, if no relief
SURGICAL INTERVENTION
80. 80
Operative assessment
Operative assessment is directed to:-
The site of obstruction
The nature of obstruction
The viability of the bowel
Identification of the caecum is the best initial
manoeuvre
If it is collapsed, the lesion is in the small
bowel
A dilated caecum indicates large bowel
81. 81
Operative assessment
cont…..
Intestine Viable Non-viable
Circulation Pink or Dark color
becoming lighter
Darker color remains
Mesentery Pulsation of
mesenteric vessels
Bleeds if pricked
No pulsation of
mesenteric vessels
Does not bleed if pricked
Peritoneum Shiny Dull and lusterless
Intestinal
musculature
Visible peristalsis No peristalsis
82. 82
Categories of Surgical
procedures
Surgical procedures for the relief of intestinal
obstruction are divided into five categories:
Procedures not requiring opening of bowel —
lysis of adhesions, manipulation-reduction of
intussusception, reduction of incarcerated hernia
Enterotomy for removal of obturation obstruction
—gallstone,
bezoars
Resection of the obstructing lesion or
strangulated bowel with primary anastomosis
Short-circuiting anastomosis around an
obstruction [bypass surgery]
Formation of a cutaneous stoma proximal to the
83. 83
Postoperative care
The principles of postoperative care are
the same as the preoperative preparation
of the patient with obstruction:-
i.v.fluids and electrolytes
Gastrointestinal decompression
Nil per oral
Antibiotics
Analgesics
84. 84
Fluid and electrolyte therapy
Given to replace the continuous loss
Given as 5% Dextrose alternate with either
R/L or N/S or hartmann’s soln in the ratio
of 3:1 3l/24 hours
i.e. 5% Dextrose : R/L 3l/24 hours [3:1]
85. 85
Decompression of the GI
tract
Post-op decompression of GIT is more
important because restoration of normal
propulsive intestinal motility usually is
significantly delayed after release of intestinal
obstruction
Bowel function usually resumes about the 5-6
days after
operation
Criteria for discontinuation of NGT after
operation include:-
86. 86
Nil orally
Restoration of normal propulsive intestinal
motility is usually delayed after release of
intestinal obstruction
The patient should be restricted from diet
until:-
Restoration of normal bowel sounds
Patient is passing flatus or stool
87. 87
Antibiotics
Should be broad-spectrum to cover both
aerobes and anaerobes
Should be given intravenously
A 3rd –generation cephalosporin,
metranidazole and gentamicin is common
primary strategy
Should be given for up to 5 days
88. 88
Analgesics
Pain control is essential to quality patient
care
Analgesics ensure patient comfort,
promote pulmonary toilet, and have
sedating properties, which are beneficial
for patients who experience pain
Usually given parenterally [i.m. or i.v.]
89. 89
Monitor
Input-output fluid chart
Vital signs [PR, RR, BP]
Resumption of bowel sounds & passage of
flatus or stool
90. 90
Follow up care
The aims of follow up include:-
To be able to detect postoperative
complications at an early stage of
treatment and thus early intervention
Stitches removal at 7-10 days
depending on the state of the wound
![Intestinal obstruction
Dr Phillipo L. Chalya M.D. ; M.Med [Surg]
Surgeon Specialist
Dept of Surgery
BMC](https://image.slidesharecdn.com/02-230104185037-a1a21ddd/85/02-intestinal-obstructiondr-phyllip-bmcppt-1-320.jpg)
