Intestinal obstruction TUOTORIAL: Dr. Mohammad Al-Akeely Assoc.prof.&consultant surgeon KKUH & KSMC

Definition Any condition that interferes with normal propulsion and passage of intestinal contents. Can involve the small bowel, colon or both small and colon as in generalized ileus.

Classification According to the cause of obstruction : mechanical(dynamic) or functional (paralytic ileus, adynamic) . According to duration of the obstruction: acute or chronic. According to the extent of obstruction : partial or complete According to the nature of obstruction : simple or complex (closed loop or strangulation) .

Mechanical obstruction There is physical blockage to intestinal content which may be due to: Intramural : congenital-tumor-hematoma-inflammatory Extramural : adhesion-volvulus-hernia –abscess-hematoma Lumen obstruction: stone-meconium-foreign body- impaction (stool-worm-barium) This mechanical obstruction can be partial ( lumen narrowed but allow transit some content) or complete ( lumen totally obstructed). Therefore complete obstruction is either: simple obstruction (no vascular impairment) closed loop ( both ends are obstructed) . strangulation obstruction

Functional (paralytic) obstruction This obstruction is commonly secondary to factors causing either paralysis or dysmotility of intestinal peristalsis. Postoperative ileus is the most common form of functional bowel obstruction following intra-abdominal operations which correlates with degree of surgical trauma and type of operation ,so patients operated on for chronic obstruction or sever peritonitis has more prolonged post op ileus. Different anatomic segments of GIT also recover at different rates after manipulation and trauma : Small bowel within hours after operation. Stomach may take 24-48 hr . Colon 3-5 days post op.

NOTE : Patients who has prolonged post op ileus ( <72 hrs)or had the ileus after a period of normal bowel sounds and motion, you should suspect complication of surgery eg: fibrinous adhesions ( cause > 90%). other causes are: Internal herniation intra-abdominal abscess intramural hematoma anastomatic edema and leak Difficult to differentiate by clinical presentation and X-ray. but CT scan is helpful .

Pathophysiology Proximal bowel: increased peristalsis, dilates(fluid&gas) Distal bowel : normal perestalsis, collapse Gas (swallowed air& fermintation by bacterial), 90% N2 Fluid (oral intake, gut secresions and gut wall leakage).

Pathophysiology Dehydration and electrolyte imbalance is due to: *reduced intake *defective absorption *vomiting *sequestration in gut

Common causes of mechanical bowel obstruction: Small bowel obstruction: Adhesion 60% Hernia 20% Neoplasm 5% Volvulus 5%. Others: IBD-GALL STONE-FOREIGN BODY-INTUSSUSCEPTION. Large bowel obstruction : Cancer 60%. Diverticular disease 15%. Volvulus 15%. Fecal impaction.

Common causes of functional bowel obstruction: Vascular occlusion ileus. Adynamic or paralytic ileus : Post operation mostly after abdominal surgery Metabolic causes: DKA- hyponateremia-hypokalemia – hypomagnesaemia. Drugs: morphine –TCA-antacid-anticonvulsant. Intra-abdominal inflammation—sepsis—occult wound infection. Pneumonia—renal stone—retroperitoneal hematoma---fracture spine and ribs

Diagnosis Four cardinal symptoms: Examination : History and physical examination: Four cardinal symptoms: (pain-vomiting-distension and obstipation). Proximal obstruction earlier symptoms with prominent projectile vomiting and less distension. While vomiting is a late feature in colon obstruction and is usually faecolent . Location and characteristic of pain differentiate between mechanical obstruction and ileus which severe –cramp localized in mid of abdomen in mechanical while diffuse and mild in ileus. Examination : Vital signs.( PR-Temp-BP) Hydration status. Abdominal exam for distention, scars, v. perestalses. Tendernes,reb. Tenderness, masses, hernias, and rectal examinations

Diagnosis Laboratory : CBC: increased hct (dehydration ) and increase in WBC. KFT: increase in BUN and creatinine . Lactate concentration (LDH) useful but not sensitive indicator for bowel ischaemia ABG: metabolic acidosis may indicate bowel ischaemia and sepses. Electrolytes: for hypo-natraemia & hypo -kalaemia

Diagnosis Radiological : erect CXR, supine and upright abdominal x ray. CXR : Detect extra-abdominal condition present with bowel obstruction e.g. pneumonia. Presence of pneumoperitoneum indicates perforated viscus. Abdominal X-RAY Small bowel considered dilated when diameter more than 3 cm while proximal colon 9 cm and the sigmoid 5 cm. Dilated small bowel tend to be in the central portion of abdomen recognized by presence plicae circularis. Dilated colon tend to be in the periphery of abdomen and recognized by haustral marking. Can be diagnostic in 50-80% of patients The cause of bowel obstruction can often determined Presence of pneumobilia suggest G.S ileus. Sigmoid and cecal volvulus produce pathognomnic images.

Supine

Diagnosis Contrast studies: Computed tomography: Gastrograffin follow through. Identify site and often the cause of obstruction. Differentiate between colonic and distal small bowel obstruction Differentiate between ileus-partial and complete obstruction. Computed tomography: Recently become valuable in diagnosis of intestinal obstruction and ischemia. It has a high sensitivity and specificity.

Treatment Resuscitation. Conservative treatment Previous surgery. Incomplete obstruction. Advanced malignancy. Uncertain diagnosis. Indications for surgery Generalized or localized peritonitis. Perforation. Irreducible hernia. Palpable mass. Virgin abdomen. Closed loop Failure to improve.

Volvulus Is an axial rotation of bowel at its mesentery which could be congenital or secondary. Small intestine, caecum, sigmoid are commonly affected. Caecal volvulus twists clockwise. (resection is required if gangrene develops)

Sigmoid volvulus The commonest type of volvulus. Anticlockwise twist. Causes: Bands, overloaded colon, large mesocolon, narrow pelvic mesocolon attachment.

Treatment of volvuls: simple: colonoscopic deflation for few days followed by colon preparation and then resection and primary anastomosis. Strangulation or perforation: urgent resection and stoma followed by reversal of stoma in 6-8 weeks. Important note: A consent for stoma is important before any laparotomy for intestinal obstruction. Bowel preparation, consent for stoma and prophylactic antibiotics are mandatory before elective colonic operations.

Now let us test our knowledge with some clinical scenarios in bowel obstruction……

Now let us some discuss some scenarios

Clinical scenario 1 32 years old male c/o gradual central colikey abdominal pain since 10 hours associated with nausea, he had a projectile greenish vomitus 2 hours ago. He passed normal stool today. No past medical history but he had appendectomy one year ago. No previous similar conditions. What is the likely diagnosis ?

Acute adhesive intestinal obstruction what are the important points in physical exam?

32 years male c/o gradual central colicky abd. pain since 10 hours 32 years male c/o gradual central colicky abd.pain since 10 hours. He is nauseated, and had a greenish projectile vomitus 2 hours ago, and passed normal stool today.No associated fever.No passed medical problems or similar attaks.He had appendectomy one year ago. Physical exam: Pulse 92/m, Bp110/82, tem.37.2c Abdomen is moving freely with respiration, mildley distended, healthy midline scar, no visible perestalsis, intact hernial orifises , no tenderness, no masses , tympanic percussion, hyper active bowel sounds and PR. exam was normal what is your impression now ?

Acute simple (uncomplicated) adhesive int. obst Acute simple (uncomplicated) adhesive int. obst. What are the required investigations?

cbc , urea, cr , electrolytes , ABG (met. alkalosis) CxR ,plain abd cbc , urea, cr , electrolytes , ABG (met.alkalosis) CxR ,plain abd.X-R Gastrografin follow through vs contrast CT.

how would you manage this case ?

Indications for surgery: Conservative treatment: admission Npo IV fluids Analgesia Folley cath Regular check of symptoms , vital signs and abdominal exam to rule out complications. Indications for surgery: Ischemia , strangulation , failure of conservative treatment (up to 5 days).

Scenario 2 42 years old lady presented to the emergency room with colikey pain at the centre of the abdomen since 2 days associated with nausea and frequent greenish vomitus. She did not pass flatus or stool since yesterday. She had laparoscopic cholecystectomy and para-umbilical hernia repair 3 years ago followed by recurrence of the para-umbilical swelling 2 years later. What is your differential diagnosis ?

1. simple obstruction (adhesion) 2 1. simple obstruction (adhesion) 2. closed loop obstruction (hernia) What further information from history & physical exam you need ?

42 years old lady presented to the emergency room with colikey pain at the centre of the abdomen since 2 days associated with nausea and frequent greenish vomitus. She did not pass flatus or stool since yesterday. she had laparoscopic cholecystectomy and para-umbilical hernia repair 3 years ago followed by recurrence of the para umbilical swelling 2 years later which became irreducible and painful since 2 days. Examination revealed: pulse 110/m, BP100/70 temp 38c. Abdomen: distended and tympanic, multiple scars, a para-umbilical swelling which is hot and tender. Hyper active bowel sounds . Now what is your most likely diagnosis ?

Strangulated recurrent para-umbilical hernia How would you manage?

Investigations: Lab: CBC, U/E, Cr Investigations: Lab: CBC, U/E, Cr. INR ,blood cross match ECG Imaging: CxR plain x ray abd.(erect & supine) CT scan

Preparation: Laparotomy: Admission NPO NG tube Folley catheter IV fluids (REPLACE ELECTROLYTES) Antibiotics Concent Laparotomy: asessment of obstructed segment of intestine. Resection for established gangrene or asessment of viability in doubtful one after releasing the obstructing ring, warming and given 100% oxygen to patient.(return of clour,pulsatil\on and peristalses).

Scenario 3 65 yars old male presented to ER c/o sudden ,sever, coliky lower abdominal pain since 3 hours, associated with nausea but no vomiting.He is habitual constipator on occasional laxatives for long time. No history of diarrhea or bleeding per rectum .No past med. History but he was admitted 6 months ago with similar problem,had colonoscopy and then offered surgery after 5 days which he refused. Physical exam: Pulse 92/m, RR 27/m, BP 130/90 mgh ,temp 36.9c. Abdomen :no scars or hernias.It is hugely distended, non tender, bowel sounds are audible. what is the diagnosis now ?

Scenario 4 65 yars old male presented to ER c/o sudden ,sever, coliky lower abdominal pain since 3 hours, associated with nausea but no vomiting.He is habitual constipator on occasional laxatives for long time.no past med. History but he was admitted 6 months ago with similar problem,offered surgery which he refused. What are the likely differential diagnosis ?

Sigmoid volvulus (un complicated) What is the diagnostic modality ?

Un complicated : colonoscopic deflation.

Complicated (ischemia or perforation): resection.

Thanks