Case study
Intestinal Obstruction
“Never let the sun rise or set on small-bowel
obstruction”
By: Omar Z. Saleh
Definitions
Intestinal Obstruction is defined as
partial or complete blockage of the
bowel that results in the failure of
intestinal contents to pass.
Intestinal obstruction can be
classified into 2 types
Dynamic Adynamic
Peristalsis is working against a
mechanical obstruction. It may Peristalsis is
accrue in an acute or chronic
form. “Mechanical Obstruction” absent (Ex.
The obstructing lesion may be:
Paralytic ileus) or it
1. Intraluminal (Ex. impacted faeces,
may be present in
foreign bodies, bezoar, gallstones)
a non-propulsive
2. Intramural (Ex. malignant or
inflammatory strictures)
form (Ex. Pseudo-
obstruction)
3. Extramural (Ex. intraperitoneal bands
and adhesions, hernias, volvulus or
intussusception.)
Other Classifications
According to…
ONSET: Acute VS Chronic
SITE: Small Bowel (High) VS Large
Bowel (Low)
NATURE: Simple VS Strangulated
Incidence
Site of Obstruction Cause Relative Incidences
(%)
Small intestine [85%] Adhesions 60
Hernia 15
Tumors 15
miscellaneous 10
Large Intestine [15%] CA colon 65
Diverticulitis 20
Volvolus 5
miscellaneous 10
Clinical Presentation
Clinical Presentation
HISTORY - The diagnosis of intestinal obstruction is based on its “cardinal symptoms”
of Pain, Distension, Vomiting and Absolute Constipation.
1) DURATION - Nature of Presentation of Obstruction will be influenced by
whether the presentation is…
I. Acute Obstruction usually occurs in small bowel obstruction with
sudden onsets of severe colicky central abdominal pain, distension,
with early vomiting and constipation.
II. Chronic obstruction is usually seen in large bowel obstruction with lower
abdominal colic and absolute constipation, followed by distension.
III. In Acute on Chronic Obstruction there is a short history of distention
and vomiting against a background of pain and constipation.
IV. Subacute Obstruction implies an incomplete obstruction. Presentation
will be further influenced by whether the obstruction simple (With blood
supply is intact) or strangulated (there is interference to blood flow)
Clinical Presentation
HISTORY - The diagnosis of intestinal obstruction is based on its “cardinal symptoms”
of Pain, Distension, Vomiting and Absolute Constipation.
2) PAIN - The Pain of intestinal obstruction is true colic, and it is the
first symptom encountered.
Site- Centered around the umbilicus (small Bowel Colic)
Lower 1/3 of Abdomen (Large Bowel Colic)
Onsite- Sudden
Character - Colicky i.e. pain caused by spasm, intermittent.
Radiation - No Radiation. Generally Periumbilical or Suprapubic.
Associated Symptoms- None.
Timing- Small Bowel colic occurs every 2-20 minutes.
Large Bowel Colic occurs about every 30 minutes or more.
Exacerbating and Relieving Factors- Corresponds with Peristalsis
Severity- Sever.
Clinical Presentation
HISTORY - The diagnosis of intestinal obstruction is based on its “cardinal symptoms”
of Pain, Distension, Vomiting and Absolute Constipation.
3)VOMITING - Frequent vomiting, nature of Vomitus
depends on the level of obstruction.
I. Pyloric Obstruction vomitus is watery and acidic.
II. High Small Bowel Obstruction vomitus is
Greenish-Blue and Bile-Stained.
III. Lower Small Bowel Obstruction vomitus is foul
smelling and Brown (Faeculent Vomit)
IV. Large Bowel Obstruction vomitus is usually a late
symptom.
Clinical Presentation
HISTORY - The diagnosis of intestinal obstruction is based on its “cardinal symptoms”
of Pain, Distension, Vomiting and Absolute Constipation.
4) DISTENTION - The lower the site of obstruction
the more bowel there is available to distend.
“Higher up” Bowel Obstruction is NOT
associated with distension.
“Colon” Obstruction causes the colon to
distend around the periphery of the abdomen
and might extend into the small bowel if the
ileocaecal valve is incompetent.
Clinical Presentation
HISTORY - The diagnosis of intestinal obstruction is based on its “cardinal symptoms”
of Pain, Distension, Vomiting and Absolute Constipation.
5) ABSOLUTE CONSTIPATION - Develops
once the block becomes complete and the
bowel below is empty, so that neither feces
nor flatus are passed.
Occurs Early in “lower” Large Bowel
Obstruction.
Occurs Late in “High” Small Bowel
Obstruction.
Clinical Presentation
HISTORY - The diagnosis of intestinal obstruction is based on its “cardinal symptoms”
of Pain, Distension, Vomiting and Absolute Constipation.
7) Late Manifestations…
Pyrexia
Respiratory Distress
Dehydration
Hypovolemic Shock
Peritonism
Clinical Presentation
EXAMINATION
1) INSPECTION - We Look For…
i. Surgical Scars
ii. Hernias
iii. Distention
iv. Visible Peristalsis
Clinical Presentation
EXAMINATION
2) PALPATION – Palpate for…
i. Masses
ii. Hernias
iii. Tenderness
Perform Rectal Exam.
Clinical Presentation
EXAMINATION
3) PERCUSSION – Percuss to hear any
Dullness or Resonance related to site of
obstruction.
Clinical Presentation
EXAMINATION
4) AUSCULTATION – Bowel Sounds are
Initially Loud and frequent→ Then as
bowel distends the sounds become more
→
resonant and high pitched→ Eventually
becoming Amphoric.
Clinical Presentation
DEFERENTIAL DIAGNOSIS
1) In The Small Bowel
I. Gallstone Ileus
II. TB
III. Tumor
IV. Adhesions
V. Volvulus
Clinical Presentation
DEFERENTIAL DIAGNOSIS
2) In The Large Bowel
I. Feces
II. Diverticulae
III. CA
IV. Hirshsprung‟s Diseases
V. Adhesions
VI. Volvulus
X-RAY
Small Bowel
Obstruction is
suggested by a
“ladder” pattern, when
obstruction occurs,
both fluid and gas
collect in the intestine.
They produce a
characteristic pattern
called air-fluid levels.
The air rises above
the fluid and there is a
flat surface at the air-
fluid interface.
X-RAY
Distended Large
Bowel Tends to lie
peripherally and to
show the
Hustrations of the
Taenia Coli.
X-RAY- “Barium Follow-Through”
Patient drinks a contrast medium containing
barium sulfate. Contrast medium appears
white on x-rays, and shows the outline of the
internal lining of the bowel.
X-ray images are taken at intervals as the
contrast moves through the intestine, (@ 0
minutes→@ 20 minutes→@ 40 minutes →
@90 minutes);
The bowel is accessed as it becomes visible.
The test is completed when the Barium is
visualized at the Caecum.
CT
Useful to detect…
• Lesions
• Colonic Tumors
• Hernias
• Bolus
Although the treatment of
specific causes of intestinal
obstruction is considered
accordingly, there are some
general principles applied.
Chronic large bowel
obstruction, slowly progressive,
and incomplete obstruction can
be investigated at some leisure.
Acute, sudden onset, complete
and obstruction with risk of
strangulation requires emergency
surgical intervention.
Preop
1. Gastric Aspiration via Nasogastric Tube; This
decompress the bowel and remove risk of
inhaling gastric contents during anesthesia.
2. IV Fluid replacement Give normal Saline,
Possibly Blood or Plasma if patient is shocked.
1. Antibiotic Therapy Started if Strangulation is
found or suspected.
Operative
Bowel is inspected and Small Bowel can be
non-viable (aka non- removed and anastomosis
functioning) bowel is performed with safety
removed. because of its rich blood
supply.
Non-Viability is determined by:
Large bowel is not as
I. Loss of peristalsis easily approachable,
where consideration must
II. Loss of Sheen be taken regarding the
III. Greenish or Black (Not location of the obstruction
Purple; Purple may still and its relation to nearby
recover) blood supply.
IV. Loss of Pulsation in
supplying vessels
Conservative
“Drip and Suck” Drip IV Fluids and Suck via Nasogastric Aspiration.
Non-Surgical Treatment is considered when
1. Distinction from postoperative paralytic ileus is
uncertain.
2. Obstruction resulted from massive intra abdominal
adhesions rendering Surgery dangerous.
Any increases of distention, aggravation of pain,
increase in abdominal tenderness, or rise in pulse
are indication to abandon conservative treatment
and re-explore the abdomen.
Pathophysiology
In obstruction, regardless of the cause of obstruction
or its acuteness of onset, the proximal bowel dilates
and develops an altered motility.
Below the obstruction, the bowel exhibits normal
peristalsis and absorption until it becomes empty,
when it contracts and becomes immobile.
Initially, proximal peristalsis is increased to overcome
the obstruction, If the obstruction is not relieved the
bowel begins to dilate causing a reduction in
peristaltic strength, ultimately resulting in flaccidity
and paralysis.
The distension proximal to an obstruction is
produced by two factors:
I. Gas - regardless of the level of
obstruction, there is a significant
overgrowth of both aerobic and anaerobic
organisms resulting in considerable gas
production.
II. Fluid - Following obstruction, fluid
accumulates within the bowel wall and
any excess is secreted into the lumen,
whilst absorption from the gut is retarded.
Dehydration is therefore due to…
1. Reduced oral intake
2. Defective intestinal absorption
3. Losses due to vomiting
4. Sequestration in the bowel lumen
Strangulation
Strangulation is impairment of blood supply to bowel.
Signs of Strangulation
• Toxic Appearance, Rapid Pulse, Temperature drop
• Colicky pain with decreasing intermittence
• Marked Tenderness and Rigidity
• Raised WBC (mainly Neutrophils), usual with
infracted bowel.
• Shock
Strangulation
Causes of strangulation-
1. External→ Hernial Orifices Adhesions/Bands
2. Interrupted Blood Flow → Volvulus
Intussusceptions
3. Increased Intraluminal Pressure → Closed-Loop
Obstruction
4. Primary → Mesenteric Infarction
Strangulation
Closed-loop obstruction
This occurs when the bowel is
obstructed at both the proximal
and distal point. There is no
early distension of the proximal
intestine.
When gangrene of the
strangulated segment is
imminent, retrograde thrombosis
of the mesenteric veins results
in distension on both sides of
the strangulated segment.
Unrelieved, this may result in
necrosis and perforation.
Dynamic (Mechanical) Obstruction
Classification according to source
A: Intraluminal
i. Impaction
ii. Foreign Bodies
iii. Bezoars
iv. Gallstones
B: Intramural
i. Stricture
ii. Malignancy
C: Extramural
i. Adhesions/Bands
ii. Hernia
iii. Volvulus
iv. Intussusceptions
Adhesions
Most common cause of obstruction in the west.
Any site of peritoneal irritation results in fibrin production, which results in
adhesions between apposed surfaces.
Only ONE adhesion may be causative of obstruction.
There are many causes of intraperitoneal adhesions such as Ischemic
Areas, Foreign Material, Infection, Inflammatory Conditions, and Radiation
Enteritis.
Adhesions may he classified into various types whether they are early
(fibrinous), late (fibrous) or by the underlying etiology. From a practical
perspective, there are only two types — „easy‟ weak ones and „difficult‟
dense ones.
Postoperative adhesions giving rise to intestinal obstruction usually involve
the lower small bowel. Operations for appendicitis and gynecological
procedures are the most common; and are an indication for early
intervention.
The following factors may limit adhesion formation:
I. Good surgical technique
II. Washing of the peritoneal cavity with saline to remove clots,
etc.
III. Minimize contact with gauze;
IV. Cover anastomosis and raw peritoneal surfaces.
V. Numerous substances have been instilled in the peritoneal
cavity to prevent adhesion formation, no single agent has
been shown to be safe and effective, and their use is not
recommended.
Treatment
Treatment of adhesions is initially
Conservative, but should not be prolonged
beyond 72hrs.
In such cases Laparotomy is required, only
causative adhesion should be removed;
removal of other adhesion will only cause
more adhesion formation.
If multiple adhesions must be removed the
bare area should be covered with omental
grafts.
Volvulus
A twisting or axial rotation of a portion of bowel about
its mesentery. When complete it forms a closed loop
of obstruction with resultant ischemia secondary to
vascular occlusion.
May be primary or secondary.
The primary form occurs secondary to congenital
malrotation of the gut, abnormal mesenteric
attachments or congenital bands.
A secondary Volvulus, which is the more common
variety, is due to actual rotation of a piece of bowel
around an acquired adhesion or stoma.
1) Volvulus Neonatorum
Due to arrest gut rotation and narrow
mesentery of small bowel and Caecum .
Symptoms include catastrophic onset of
repeated vomiting, rapid dehydration
and abdominal distension
2) Volvulus of Small Intestine
Primary or secondary and usually in
the lower ileum
Spontaneously or secondary
Treatment consists of reduction of the
twist and directed to the underlying
cause .
3) Cecal Volvulus
Primary or as a part of Volvulus Neonatorum .
A clockwise twist ·
F>M .
Acute features of obstruction .
25% has tympanic swelling in the midline or
left side of the abdomen .
4) Sigmoid Volvulus
An anticlockwise twist .
Most Common spontaneous Volvulus in
Adults.
Chronic constipation is a predisposing
factor.
Bolus Obstruction.
Accumulation → Compaction”
“
I. Gallstones: Gallstone Ileus (stones enter the
intestine through a fistulous communication
between the bile duct and the GI tract)
II. Food: Bolus obstruction may occur after partial or
total gastrectomy when unchewed articles can pass
directly into small bowel
III. Bezoars: Trichobezoars (Hair Balls) and
Phytobezoar (Fruit/Vegetable Fibre).
IV. Worms: Ascaris lumbricoides may cause low small
bowel obstruction particularly in children, the
institutionalized and those near the tropics.
Internal Hernia
Occurs where a portion of the small
intestine becomes entrapped in one of the
retroperitoneal fossae or into a congenital
mesenteric defect.
In the absence of adhesions hernia is
uncommon to cause obstruction and a
preoperative diagnosis is unusual.
The standard treatment for a hernia is to
release the constricting agent by division.
Obstruction from Enteric Strictures
Small bowel strictures usually occur secondary
to Tuberculosis or Crohn‟s disease.
Malignant strictures associated with lymphoma
are common, whilst carcinoma and sarcoma
are rare.
Presentation is usually Subacute or Chronic.
Standard surgical management consists of
resection and anastomosis.
Acute Intussusception
Most common in children.
Primary or secondary to intestinal
pathology, e.g. polyp, Meckel's
diverticullum.
Ileocolic is the most common variant.
Can lead to an ischemic segment and
strangulation.
Adynamic Obstruction
I. Paralytic Ileus
II. Pseudo-Obstruction
III. Acute Mesenteric Ischemia
Paralytic ileus
Definition: A state in which there is failure of
transmission of peristaltic wave secondary to
neuromuscular failure
This will leads to signs of intestinal obstruction due to
accumulation of gas and fluid in the bowel with signs of
abdominal distension ,constipation, but NO Pain.
Varieties :
1. Post operative: - Self limiting, Lasts for 24-72 Hours
2. Infection: Peritonitis
3. Reflex ileus: as in fracture of the spine or ribs on in
retroperitoneal hemorrhage
4. Metabolic : Hypokalemia, DM
5. Drugs : Spasmolytic Drugs , Parkinson Drugs, Atropine
Clinical features:
-It takes clinical significance if there has
been no return of normal bowel sound
and no passage of flatus after 72 hrs of
Surgery
- Abdominal distension is marked,
Effortless Vomiting, but pain is NOT a
feature
-Radiologically: Multiple Fluid Level
Management :
1. General principles must be applied if the disease
takes place
2. Remove the cause
3. Relieve GI distension by decompression
4. Monitoring fluid and electrolyte balance
5. Rarely medical agents are used (AntiCholene
Esterase)
6. Laparotomy after 72 hours
Pseudo-Obstruction
This condition describes an obstruction,
usually of the colon, in the absence of a
mechanical cause or acute intra-
abdominal disease.
It is associated with a variety of
syndromes where there is an underlying
neuropathy and/or myopathy.
1) Small intestinal pseudo-obstruction
• This condition may be primary or
secondary.
• The clinical picture consists of recurrent
subacute obstruction.
• The diagnosis is made by the exclusion
of a mechanical cause.
• Treatment consists of initial correction
of any underlying disorder.
2) Colonic pseudo-obstruction.
• This may occur in an acute or a chronic
form.
• The acute form is known as Ogilvie
syndrome, presents as acute large bowel
obstruction.
• Abdominal radiographs show evidence of
colonic obstruction with marked caecal
distension being a common feature
• Perforation is a common complication.
• Treated by colonoscopic decompression
Thank You