2. BOWEL OBSTRUCTION OVERVIEW
CLASSIFICATION
COMMON CAUSES OF OBSTRUCTION
CLINICAL FEATURES
INVESTIGATION
TREATMENT
3. INTRODUCTION
Accounts for 5% of all acute surgical admissions
Patients are often extremely ill requiring prompt assessment, resuscitation
and intensive monitoring
Types:
Obstruction:
A mechanical blockage arising from a structural abnormality that presents
a physical barrier to the progression of gut contents.
Ileus:
is a paralytic or functional variety of obstruction
Obstruction is:
Partial or complete
Simple or strangulated
4. CLASSIFICATION
Result from atony of the
intestine with loss of
normal peristalsis, in the
absence of a mechanical
cause.
or it may be present
in a non-propulsive
form (e.g. mesenteric
vascular occlusion or
pseudo-obstruction)
ADYNAMIC
(FUNCTIONAL)
Result from atony of the
intestine with loss of
normal peristalsis, in the
absence of a mechanical
cause.
or it may be present
in a non-propulsive
form (e.g. mesenteric
vascular occlusion or
pseudo-obstruction)
ADYNAMIC
(FUNCTIONAL)
8. Peritoneal irritation local fibrin production produces adhesions between
apposed surfaces
As early as 4 weeks post laparotomy. The majority of patients present
between 1-5 years
Colorectal Surgery 25%
Gynaecological 20%
Appendectomy 14%
Prevention: good surgical technique, washing of the peritoneal cavity with
saline to remove clots, etc, minimizing contact w/ gauze, covering
anastomosis & raw peritoneal surfaces
9. TREATMENT OF ADHESIVE
OBSTRUCTION
Initially treat conservatively provided there is no signs of
strangulation; should rarely continue conservative
treatment for longer than 72 hours
At operation, divide only the causative adhesion and
limit dissection
Laparoscopic adhesiolysis in cases of chronic
subacute obstruction
10. Hernia
Accounts for 20% of SBO
Commonest 1. Femoral hernia
2. ID inguinal
3. Umbilical
4. Others: incisional
The site of obstruction is the neck of hernia
The compromised viscus is with in the sac.
Ischaemia occurs initially by venous occlusion, followed by oedema and
arterial compromise.
Attempt to distinguish the difference between:
Incarceration
Sliding
Obstruction
Strangulation is noted by:
Persistent pain
Discolouration
Tenderness
Constitutional symptoms
11. Volvulus
A twisting or axial rotation of
a portion of bowel about its
mesentery. When complete it
forms a closed loop
obstruction ischemia
Commonest spontaneous
type in adult is sigmoid, can
be relieved by
decompression per anum
Surgery is required to prevent
or relieve ischaemia
Features: palpable tympanic lump
(sausage shape) in the midline or
left side of abdomen.
Constipation, abdominal
distension (early & progressive)
12.
13. ACUTE INTUSSUSEPTION
Occurs when one portion of the gut becomes invaginated within an
immediately adjacent segment.
Common in 1st year of life
Common after viral illness enlargement of Peyer’s patches
Ileocolic is the commonest variety in child.
Colocolic intussusception commonest in adult
An intussusception is composed of three parts :
the entering or inner tube;
the returning or middle tube;
the sheath or outer tube (intussuscipiens).
14. Classically, a previously healthy infant presents
with colicky pain and vomiting (milk then bile).
Between episodes the child initially appears well.
Later, they may pass a ‘redcurrant jelly’ stool.
15.
16. LARGE BOWEL OBSTRUCTION
Distinguishing ileus from mechanical obstruction is challenging
Caecum is at the greatest risk of perforation
Perforation results in the release of formed feaces with heavy bacterial
contamination
Aetiology:
1. Carcinoma:
The commonest cause, 18% of colonic ca. present with obstruction
2. Benign stricture:
Due to Diverticular disease, Ischemia, Inflammatory bowel disease.
3. Volvulus:
-Sigmoid Volvulus/ Caecal Volvulus
4. Hernia.
5. Congenital : HirschPrung, anal stenosis and agenesis
17. CLINICAL FEATURES
Large bowel obstruction
distension is early and pronounced.
Pain is mild and vomiting and dehydration are late.
The proximal colon and caecum are distended on abdominal radiography
CARDINAL FEATURES:
Colicky pain
Vomiting
Abd distention
Constipation
OTHER FEATURES:
Dehydration
Hypokalaemia
Pyrexia
Abd tenderness
18. PHYSICAL EXAMINATION
INSPECTION
Abdominal distention, scars, visible peristalsis.
PALPATION
Mass, tenderness, guarding
PERCUSSION
Tymphanic, dullness
AUSCULTATION
Bowel sound are high pitch and increase in frequency
19. INVESTIGATIONS:
Lab:
FBC (leukocytosis, anaemia, hematocrit, platelets)
Clotting profile
Arterial blood gasses
U& Crt, Na, K, Amylase, LFT and glucose, LDH
Group and save (x-match if needed)
Optional (ESR, CRP, Hepatitis profile)
RadiOlogical:
Plain ABDOMINAL xrays
USS ( free fluid, masses, mucosal folds, pattern of paristalsis, Doppler of mesenteric
vasulature, solid organs)
Other advanced studies (CT, MRI, Contrast studieS)
20. Fluid levels with gas above;
‘stepladder pattern’. Ileal
obstruction by adhesions;
patient erect.
Supine radiograph from a patient with
complete small bowel obstruction
shows distended small bowel loops in
the central abdomen with prominent
valvulae conniventes (small white
arrow)
Figure 3. Lateral decubitus
view of the abdomen, showing
air-fluid levels consistent with
intestinal obstruction (arrows).
21. In small bowel
Central 3cm thick
diameter
Vulvulae coniventae
Ileum may occur
tubeless
In large bowel
Peripheral diameter 6cm
Presence of haustration
22. ROLE OF CT
Used with iv contrast, oral and rectal
contrast (triple contrast).
Able to demonstrate abnormality in the
bowel wall, mesentery, mesenteric vessels
and peritoneum.
It can define:
the level of obstruction
The degree of obstruction
The cause: volvulus, hernia, luminal and
mural causes
The degree of ischaemia
Free fluid and gas
Ensure: patient vitally stable with no renal
failure and no previous alergy to iodine
• FIGURE: AXIAL COMPUTED TOMOGRAPHY SCAN SHOWING
DILATED, CONTRAST-FILLED LOOPS OF BOWEL ON THE
PATIENT’S LEFT (YELLOW ARROWS), WITH DECOMPRESSED
DISTAL SMALL BOWEL ON THE PATIENT’S RIGHT (RED
ARROWS). THE CAUSE OF OBSTRUCTION, AN
INCARCERATED UMBILICAL HERNIA, CAN ALSO BE SEEN
(GREEN ARROW), WITH PROXIMALLY DILATED BOWEL
ENTERING THE HERNIA AND DECOMPRESSED BOWEL
EXITING THE HERNIA.
23. CONTRAST STUDIES
Barium should not be used in
a patient with peritonitis
As: follow through, enema
Limited use in the acute setting
Gastrografin is used in acute
abdomen but is diluted
Useful in recurrent and chronic
obstruction
May able to define the level and
mural causes.
Can be used to distinguish
adynamic and mechanical
obstruction
24.
25.
26. TREATMENT OF INTESTINAL
OBSTRUCTION
Supportive
1. Resuscitation
2. Ryle tube free flow with 4 hourly aspiration
-Decompression of proximal to the obstruction, reduce subsequent aspiration
during induction of anesthesia and post extubation.
3. IV drip normal saline / Hartmann (Sodium & water loss during IO)
4. Broad spectrum antibiotic (not mandatory but need in all patient
undergoing surgery.
27. MANAGEMENT FOR LARGE BOWEL
OBSTRUCTION
All patients require
•Adequate resuscitation
•Prophylactic antibiotics
•Consenting and marking for potential stoma formation
•At operation
•Full laparotomy should be performed
•Liver should be palpated for metastases
•Colon should be inspected for synchronous tumours
•Appropriate operations include:
•Right sided lesions – right hemicolectomy
•Transverse colonic lesion – extended right hemicolectomy
•Left sided lesions – various options
28. INDICATIONS FOR SURGERY
Generalised peritonitis
Localised peritonitis
Visceral perforation
Irreducible hernia
Palpable mass lesion
Failure to improve
Advanced malignancy
Incomplete obstruction
Advanced malignancy
29. SURGERY
Three-staged procedure
Defunctioning colostomy
Resection and anastomosis
Closure of colostomy
Two-staged procedure
Hartmann’s procedure: the
surgical resection of
the rectosigmoid colon with
closure of the rectal stump and
formation of an end colostomy. It
was used to treat colon
cancer or diverticulitis
Closure of colostomy
30.
31. Complications associated with
intestinal obstruction repair
include excessive bleeding
infection
formation of abscesses (pockets of pus)
leakage of stool from an anastomosis
adhesion formation
paralytic ileus (temporary paralysis of the intestines)
reoccurrence of the obstruction.
32. PARALYTIC ILEUS
A state in which there is a failure of transmission of peristaltic
waves 2° to neuromuscular failure ( in Auerbach’s and
Meissner’s plexuses)
Stasis leads to accumulation of fluid and gas within bowel
a/w distension, vomiting, absence of bowel sound and
absolute constipation
Varieties factors: postoperative, infection, reflex ileus and
metabolic
Radiological: gas filled loops of intestines with multiple fluid
levels
33. Management:
Essence of treatment prevention with use of
nasogastric suction and restriction of oral intake until
bowel sound and passage of flatus return
Maintain electrolyte balance
Specific treatment:
Removed primary cause
Decompressed GI distension
If prolong paralytic ileus , consider laparotomy exclude
hidden cause and facilitate bowel decompression