INTESTINAL OBSTRUCTION
INTESTINAL OBSTRUCTION
when there is pathological interference with the normal progration of the intestinal luminal contents distally, the condition is called intestinal obstruction.
CLASSIFICATION• 1, Mechanical obstruction • obturation obstructoin• lesions in the intestinal wall• lesions extrinsic to the bowel.• 2, Nonmechanical obstruction• dynamic ileus----->including paralytic ileus/blood ileus• 3, simple mechanical obstruction
- strangulated obstruction• - closed loop obstruction• 4, Acute
-chronic
-Acute on chronic obstruction
Obturation obstructoin
• Meconium
• Hair,fruit and vegetable fibers
• Gall stone
• Polypoid tumour of bowel.
• Interssusception
• Impaction of barium
• worms
lesions in the intestinal wall
• Congenital-Atresia,stenosis,megacolon,Meckle diverticulum,imperferforete anus etc
• Traumatic-• Inflammatory-
Chohn’s disease,ulcerative colitis• Noeplastic-tumoures• Miscellaneous-
Radiation, post op stenosis
lesions extrinsic to the bowel.
• Adhesive band constriction or angulation by adhesion.
• External hernia
• Volvulus
• Extrinsic mass-haematoma,abscess,neoplasms outside/inside the bowel
Nonmechanical obstruction
• Paralytic ileus-
(failure of transmission of peristalsis wave due to neuromuscular failure)
Types-Post operative
-peritonitis
-metabolic
reflex–retroperitoneal abscess, # vertebra
simple mechanical obstruction
• Obstruction
• Blood supply remain intact
strangulated obstruction
• Obstruction
• Mesenteric vessels involved.
• Emergency ,required surgery.
• Causes-
1.Adhesive band obstruction
2.Hernia
3.Volvulus
4. intussuception
closed loop obstruction
• When the afferent and efferent loop are obstructed
• Both limb of loop obstructed.
• Neither progression.
• Nor regratation.
• emergency
Acute
• Central abdominal pain
• Early vomiting
• Central abdominal distention
• Constipation later on disention
Chronic
• Obstruction is confined to the large bowel
• Lower abdominal pain
• Absolute constipation later on dist
Acute on chronic obstruction
• Start in large intestine-gradually small intestine involved.
• Early pain
• Constipation
• Vomiting
• Abdominal distantion.
PATHOPHYSIOLOGY
• Adhesion -40%
• Due to obstructed hernia-12 %
• Inflammatory- 15 %
• Ca-15 %
• Faecal impaction-8%
• Pseudo-obstruction-5%
• Miscellaneous-5%
Bowel motility
• When the intestine is obstructed the part of the intestine above the obstruction shows vigorous peristalsis to overcome the obstruction
• Duration-2 to 4 days.• More distal obstruction-more vigorous peristalsis with longer
duration• If obstruction not relived-
-Intestine ensues
-Peristalsis ceases
-Obstructed intestine flaccid
-paralysis
• For a few hours the intestine below the obstruction shows normal peristalsis and absorption
• This empty contain
-Immobile
-Contracted
-Pale.
Distention
• Accumulation of fluid and gas proximal to the obstruction
• distention.
• (ingested fluid, digestive secretion and intestinal gas)
• Bacterial proliferation
Fluid and electrolyte imbalance• Large volume of saliva, gastric secretion, bile and pancreatic juice
enter gut daily.• These are menially absorbed in small intestine • Distention increases intestinal secretion and decreases absorption.• Fluid accumulation-proximal to onstruction
various digestive juice-8000 ml /day
saliva--------------------1500ml /day
gastric juice-----------2500 ml /day
pancreatic juice--------1000 ml /day• Repeated Vomiting
• (vomiting and fluid collection leads to-loss of water,Na,Cl,H,K ions producing metabolic alkolosis,hypocalamia and dehydration)
• Dehydration-
-------------Oliguria
------------Reduced cardiac output
-Low CVP
-Hypotension
-Hypovolaemic shock
Intestinal gases
Most of distention caused by accumulation of
1. Swallowed gas
2. Organic gas
(hydrogen sulphied,ammonia,hydrogen and amines)
3. Diffusion from blood (CO2)
4. Bacterial fermentation
(70 % nitrogen,12% O2,CO2-8%,Remaining 10%)
CLINICAL FEATURES
• 1, Abdominal pain
• 2, Vomiting
• 3, constipation
• 4, Distention
Abdominal pain• First symptom
• Sudden onset
• Cramping in nature
• With 4 to 5 min interval
• Upper abdominal-high obstruction
Umbelicus-ileal obstruction
Lower abdominal-colon obstruction
Perineum-rectisigmoid obstruction
• Poorly localized
• Continuous sever pain without any quiescent period --STRANGULATION
Vomiting• Early vomiting is reflex-followed by quiescent period• Interval of vomiting depends on site of Obstruction• High obstruction-frequent-copious colour-relived by
decompression• Low small bowel obstruction-less frequient/does not
get relief• In acute small bowel obstruction character of vomit
alters -initially partly digested food-yellow/green-finally faeculent
• IN COLON OBSTRUCTION VOMITING IS ABSENT
constipation
• There may be one or two natural action of bowel
• IN FEW CONDITION LIKE RICHTER’S HERNIA,MESENTRIC VASCULAR OCCLUSION CONSTIPATION MAY NOT BE PRESENT.
Distention
• In early small bowel obstruction there may not be any abdominal distention.
• Distention is less in –high small B.A.
Centrally located - low small B.A.
• Visible peristalsis
• High sound
Physical Examination• Tachycardia and hypotension indicate sever dehydration and/or
peritonitis.• Degree of dehydration axamin-skin turgor and moisture of the
mucous membrane • Fever suggest –strangulation• GC-POOR-sever illness .• 1, Inspection : • peristalsis (long standing obstruction), • state of nutrition , • behavior ,skin color , and turgor , • surgical scar,• Abdominal distention,• fluid thrill, • shifting dullness, • fullness in flank• All hernial orifices examination
• 2, Palpation :
• demonstrating the sites of the distress, then localizing the anatomic areas of possible abnormality.
• Garding/rigidity
• Skin temperature (Local site /general body )
• Rebond tenderness
• Mass/lump
• 3,Purcussion
• Tenderness on slight percussion suggest strangulation.
• 3, Auscultation :
• it is of great value. simple one ----noisy and is heard as rushes. During attacks of colic ,the sounds become loud ,high-pitched and metallic .
• In paralytic ileus no sound will heard.
• 4, Digital examination of the rectum
• 5,sigmoidoscopy examination
Systemic Effects of Obstruction
• 1, water and electrolyte losses
• 2, toxic materials and toxemia
• 3, cardiopulmonary dysfunction
• 4, shock
Laboratory Examination
• 1, complete blood count normal/slight raised W.B.C.-Simple mechanical obstruction.
Moderate(15000 to 20000) raised W.B.C.-Strangulation.
Very high raised (30000 to 40000).-primary mesenteric vascular occlusion
• 2, serum electrolytes and amylase determination• 3, arterial blood gas analysis• 4, urine specific gravity test • 5,blood gas analysis
Radiologic Examination• X-ray is the most important diagnostic procedure. Intestinal
gas often is found. Not so often. Sometimes can display the intestinal loop.
• Straight X-ray abdomen-AP and lateral• Lt lateral or decubitus • Gas-fluid level –highly suggestive of I.O./P.I.• Houstral fold • Straight pipe- CHARACTER LESS • Normally infants under 2 yr of age shows a few fluid level• Fluid level appears later than gas Shadows.• No.of fluid level =degree and site of obstruction. • BARIUM ENEMA
DIAGNOSIS• 1, Whether obstruction : according to clinical
manifestation ,we can know.
• 2, Mechanical or dynamic one .
• 3, Simple or strangulated one.
•
• Differentiation :• 1, continuous rather than intermittent pain .• 2, the presence of shock and rapid pulse,
elevated temperature and white blood count.• 3, the presence of peritoneal irritation• 4, a palpable tender abdominal mass.
• 5, vomitus , gastrointestinal decompression is
bloody.• 6, active non operative treatment is no use.• 7, X-ray examination show isolated. large
intestinal loop.
TREATMENT
Nonoperative Treatment
• Basic treatment :• 1, redress water , electrolyte and acid-base balance
2, gastrointestinal decompression .
. 3, antibiotic treatment.
• Fluid and electrolyte therapy-• 18 no venous catheter• Site –Superior vena cava• Urine catheterization• RL,D-5%,• Potassium• In sever dehydration-3.5 lit/day• And later on 2.5 lit/day + nasogastric
aspirated fluid• Rate-according to CVP
gastrointestinal decompression
• Short tube (Levin)
• Long tube (Miller-Abott)
Surgical Treatment• 1, principle of operation (when to operate)
For strangulation and closed-loop obstruction
the operation is required as soon as possible.
2, For simple one ,if the non operative method is no use ,the operation is needed.
• Within 24 hr.
• A period of preparation is required except in strangulation, closed loop obstruction
• Type of anaesthesia- G.A.• Incision-midline vertical• After opening –presence or absence of fluid noted
with colour• Straw colour-simple obstruction• Bloodly-strangulation• Caecum has to be searched• If Caecum grossly distended-obstruction is in
colon.• And if collapsed-small bowel
Whether the affected segment is viable or not
• Colour
• Motility
• Arterial pulsation
The Procedure of Operation• Procedures not requiting opening of bowel
• Enterotomy for removal of obturation obstruction
• Resection of the obstructing lesion or strangulated bowel with primary anastomosis.
• Bypass anastomosis around an obstruction.
• The selection depend on the etiological causes.
colostomy• If obstruction in Right colon-
Right colectomy with ileotransverse
colostomy.
If obstruction in Left colon-
3 stage –
proximal defunctioning colostomy
anastomosis
closer of colostomy
Postoperative Care
• The principles are :
fluid and electrolyte management ,
antibiotics and
gastrointestinal decompression.
Common Types of Intestinal Obstruction
Peritoneal Adhesions and Bands
• Congenital : less
• Acquired : more usual. Most are due to injure ,operation and infection.
Diagnosis
• 1, History of operation, injure ,infection.
• 2, Clinical manifestation .
• 3, maybe no manifestation in long time , suddenly the symptoms appears ,and the pain is severe.
PROPHYLAXIS • 1, Avoiding any unnecessary trauma ,strangulation
of tissue and contamination during operative procedures.
• 2, All debris should be removed and any unnecessary foreign material, excessive suture material and mass ligation in the wound should be avoided.
TREATMENT
• 1, Intestinal decompression by nasogastric incubation.
• 2, operation : sewing the intestine to itself so that the loops of intestine are arranged in an orderly ,ladder like fashion.
VOLVULUS• Volvulus is a twisting or rotation of bowel upon its
mesentery , often resulting in intestinal obstruction. Circulatory impairment may follow , particularly when the twist is more than 180 degree .
• Common site-
• 90 % sigmoid colon-Sigmoid –anticlockwise
rotates.
• Occasionally 10% in caecum-clockwise rotates.
• In transverse colon extremely rare
DIAGNOSIS
• 1, Sigmoid volvulus :
• 1,common in the elderly with chronic constipation,neurologic disease indivuduals
• 2, cramping abdominal pain is a constant complaint.
• 3, nausea and vomiting are inconstant symptoms. And tend to occur late
• 4, there is an enormous gas -filled loop of the large intestine.
• 2, Small bowel volvulus :
• 1, common in the young person.
• 2, presents following labor activity after eating.
• 3, sudden onset of severe abdominal pain ,nausea, vomiting and distention.
• 4, shock in the early stage with the necrosis of a large segment or entire small intestine.
• 5, not easy differentiated from other types of mechanical intestinal obstruction until laparotomy.
TREATMENT
• 1, Sigmoidoscopic reduction with a large rectal tube or fiber optic colonoscopic reduction.
• 2, The most volvulus should be approached by transabdominal operation , and the surgeon should choose the necessary procedure.
INTUSSUSCEPTION • 1, An intussusception is an invagination of part of
the intestinal tract into the lumen of the adjacent intestine.
• 2, 80% of intussusception occur in children under 2 years. In adults ,in contrast to children, the cause is usually related to intestinal tumors.
• Proximal to distal is commonly seen• When it is distal it proximal it is called
retrograde intussception• Compound type• AETIOLOGY• Primary –no definite cause• Secondary –polyp,ca,submucous
lipama,stump of appendix
TREATMENT• 1,Hydrostatic pressure
• 2, use barium enema
• 3, resection of the involved bowel including the leading point with end-to-end anastomosis.
Pseudo-Obstruction of The Colon• 1, Cause : surgical or blunt trauma but may be related
to other extracolonic or extraabdominal disease.
• 2, Signs: massive dilatation of the cecum and ascending and transverse colon with no vomiting and no peritoneal signs. No air in distal portion of colon.
• 3, Treatment: conservative methods. If conservative methods fail ,and cecum is greater than 12cm, laparotomy is indicated. And if signs of acute abdomen. Usually cecostomy is the choice.