Large Bowel Obstruction

Surgery 2

Large Bowel Obstruction & colostomies

Moneer Almadani MD, FACS, F.MAS

Objectives

• Introduction
• Large bowel obstruction
  • Causes
  • Diagnosis
  • Treatment
  • Complications
• Diverticular disease
• Colon volvulus
• Colostomies

Introduction

General Anatomy

• The colon is a 5-6–ft long, inverted, U-shaped.
• Cecum (and appendix) and ano-rectum, which are parts of the large intestine, are not included in the colon.

Ascending Colon

• Starts from a proximal blind end (pouch) called the cecum.
• The ascending colon takes a right-angled turn just below the liver (hepatic flexure) and becomes the transverse colon

Transverse & Descending Colon

• Transverse colon: has a horizontal course from right to left, occupying the right hypochondrium, epigastrium, and left hypochondrium.
• At splenic flexure, it is attached to the diaphragm by the phrenocolic ligament) and becomes the descending colon,
• Splenic flexure is higher (cranial) to hepatic flexure.
• Descending colon: leads to the inverted V-shaped sigmoid colon, which then becomes the rectum at the S3 level

Peritoneal Relations

• Ascending, & descending parts of the colon are retroperitoneal
• The transverse colon and the sigmoid colon have a mesentery
• Cecum is intraperitoneal but uses the mesentery of the ileum.

Teniae Coli & Omental Appendages

• Teniae coli are present in large bowel, but not present in the rectum.
• Appendages of fat, containing small blood vessels, called omental appendages (appendices epiploicae) are attached to colon.

Paracolic Gutters

• Lateral to ascending and descending colon are the right and left gutters of the peritoneal cavity,
• Fluid/pus in the upper abdomen can trickle down into the pelvic cavity.

Blood Supply

• Superior mesenteric artery through its right colic and middle colic branches
• Inferior mesenteric artery through its left colic and multiple sigmoid branches.
• Vasa recta are terminal branches of these arteries entering the colonic wall

Layers of the Colon Wall

• The colon has 4 layers:

1. Mucosa:
   • Columnar epithelium with a large number of mucus secreting goblet cells
   • No villi,
2. Submucosa
   • Contains the blood vessels and Meissner nerve plexus.
3. Muscularis propria
   • Contains the inner circular and outer longitudinal
   • Muscles and myenteric (Auerbach) nerve plexus
4. Serosa outermost layer
   • visceral peritoneum.

Functions

• Functions: you have to provide these after colonic surgery
  • Absorption of water, and electrolytes (Na, K+)
  • Normal flora manufacture-
  • Formation of vitamin K, & B complex (colonic bacteria)
  • Storage and expulsion of feces

Large bowel obstruction

Definition & Classification

• Impedance to the normal propulsive action through intestine
• It is an emergency condition that requires early identification and intervention.
• Colonic obstruction is more common in elderly individuals

✓ Acute Vs chronic Subacute: slowly but new progress

• ✓ Complete vs Partial
• Mechanical vs pseudo-obstruction

Symptoms

• Crampy abdominal pain, poorly defined
• Abdominal distention
• Altered bowel habits (Constipation) = in complete obstruction
• Nausea and vomiting
• Symptoms of complications( perforation, peritonitis)
• Other symptoms that may be diagnostically significant include the following:
  • Abrupt onset of symptoms (acute obstruction)
  • Recurrent left lower quadrant abdominal pain over several years (suggestive of diverticulitis, a diverticular stricture)
  • Chronic constipation, long-term cathartic use, and straining at stools (diverticulitis or carcinoma)
  • Changes in stool caliber (suggestive of carcinoma)
• Rectal bleeding ⇒ tumor in easterly
• Incomplete evacuation ⇒ tumor

Signs

• Abdomen (inspection, auscultation, percussion, and palpation)
• Evaluate bowel sounds, tenderness, rigidity, guarding, and any mass or fullness
• Inguinal and femoral regions, look for a possible incarcerated hernia
• Rectum, contents of anal vault, and stool consistency; perform fecal occult blood testing as appropriate

Pathophysiology

• Increased contraction of bowel proximal to obstruction
• To overcome the obstruction, proximal dilatation, and distension
• Mucosal edema and impaired venous and arterial blood flow
• Increase the mucosal permeability of the bowel
• Bacteria translocation makes Large bowel obstruction more serious
• Electrolytes imbalance, gross distension, 3rd space fluid loss
• Ileus formation+ dehydration
• Toxemia
• Further vascular compromization
• Perforation

Etiology (Different Classifications)

• Neoplasm (benign or malignant) 60%
• Stricture (diverticular or ischemic) 10 %
• Volvulus (Sigmoid, Caecal) 5%
• Hernia
• Fecal Impaction
• Adynamic

Dynamic

• Intraluminal
  • Fecal impaction
  • Foreign body
  • Bezoars
  • Gall stones
• Intramural
  • Stricture
  • malignancy
• Extramural
  • Adhesions & bands
  • Hernias (internal – external)
  • Volvulous
  • Intussception

Adynamic

• Paralytic ilus
• Mesenteric vascular occlusion
• Pseudo obstruction

Diagnosis: Laboratory Tests

• Complete blood count (CBC) : WBC, HB, Hematocrit
• Coagulation
• Electrolytes
• LFT
• Serum lactate (if bowel ischemia is a consideration)
• Urinalysis
• Stool guaiac test

Diagnosis: Imaging & Endoscopy

• Radiology Imaging
  • Plain radiography (flat and upright)
  • Contrast radiography with enema
  • Computed tomography (CT)
    • This is the imaging modality of choice in any
    • Able to confirm the diagnosis!!
    • Able to confirm the diagnosis!!
    • Localize the level of obstruction
    • Able to identify the cause.
    • Complications
    • and assess the vascularity
• Colonoscopy / Bx Biobsy
  • ↓ Cause more distention I may Cause perforation
  • → so you have to do cleansing enema.
  • no role of of Clonoscopy in acute case of obstruction
  • → no role of endoscopy in acute case of small bowel obstruction

Imaging Findings (Early & Advanced Stages)

• In early stages: colonic distension:
  • Gaseous secondary to gas-producing organisms in faeces
  • Collapsed distal colon
  • ve rebound tenderness
• In advanced cases one may see the stigmata of an ischaemic colon, namely:
  • Intramural gas (pneumatosis coli)
  • Portal venous gas
  • Free intra-abdominal gas (pneumoperitoneum)

Management: Supportive Measures

• Nil By Mouth
• Intake- output charts
• IV lines, and rehydration (IV crystalloid with K⁺)
• Foley catheter
• NG Tube to aspirate content for ‘decompression’
• TED stockings, DVT prophylaxis
• Antibiotics
• Antiemetics
• Analgesia

Management: Surgery

• exploratory laparotomy.
• Surgery: indication:
  • Perforation
  • Closed loop obstructions
  • Sepsis
  • Bowel ischemia
  • Volvulus
  • Hernia, stone or foreign body

Ogilvie syndrome

• Loss of peristalsis and results in the accumulation of gas and fluid in the colon.
• Unclear pathophysiology
• Autonomic imbalance
  • Decreased parasympathetic tone
  • Excessive sympathetic output.
• Medical or surgical illnesses.
• Complications: colonic ischemia or perforation
• The right colon and cecum are most commonly involved.
• Risk of perforation (3% -15%)

Diverticular diseases

Diverticulosis

• Includes a spectrum of conditions
• Asymptomatic vs symptomatic
• Acute vs chronic
• Complicated vs non complicated
• Diverticulosis:
  • Small pouches due to herniation of the mucosa into colonic wall
  • Commonest pathology responsible for lower GI bleeding
  • False diverticula
    • because not all layers involve

Diverticulitis

• Diverticulitis: Pain in LL abdomen
• Inflammation of diverticula, due to obstruction by fecalith
• Usually affects elderly
• 20% of patients with diverticulitis are younger than 50 years.
• In chronic form, patients may have recurrent low-grade diverticulitis.

Signs and Symptoms

• Depends on the location, the severity of the inflammatory process, and the presence of complications.
  • Abdominal pain:
    • Left lower quadrant: (70% of patients), as most diverticula occur in the sigmoid colon
    • Right lower quadrant tenderness, mimicking acute appendicitis, can occur in right-sided diverticulitis
  • Change in bowel habits
    • Nausea and vomiting
    • Constipation
    • Diarrhea
    • Flatulence
    • Bloating

Complications

• Bleeding
• Perforation/ Abscess:
  • Generalized tenderness with rebound and guarding
  • Distended and tympanic abdomen
  • Bowel sounds can be diminished or absent
  • Tender palpable mass (Abscess formation)
• Fistula:
  • Colovaginal : purulent vaginal discharge
  • Colovesicular: urinary tract symptoms (eg, suprapubic, flank, or costovertebral angle tenderness) or pneumaturia, and sometimes fecaluria
• Stricture/ obstruction

Diagnosis: Laboratory Tests

• Usually made on the basis of history and physical examination,
• Laboratory tests
  • CBC: high WBC, Hb,
  • Electrolytes,
  • Renal function,
  • LFT
  • Urinalysis / culture
  • Blood cultures
  • Pregnancy test

Diagnosis: Radiology Imaging

• Plain abdominal radiograph series
• Contrast enema,
  • Water-soluble medium,
  • Mild-to-moderate uncomplicated cases
• CT abdomen with contrast gold standard
  • Best imaging method to confirm the diagnosis.
  • Sensitivity and specificity 97%
  • Bowel wall thickening
  • Soft-tissue inflammatory masses
  • Complications, exclude other pathology

Hinchey’s Classification

• Clinical staging
• To chose the proper management option

Hinchey grade I	Localised para-colonic abscess
Hinchey grade II	Distant abscess (e.g. pelvic, sub-phrenic)
Hinchey grade III	Purulent peritonitis
Hinchey grade IV	Faecal peritonitis

Management

• Conservative: (mild cases)
  • Initiate bowel rest and intravenous fluid hydration
  • Broad-spectrum intravenous antibiotic Within 2-3 days of hospitalization, fever, pain, and leukocytosis should begin to resolve
  • Start on a clear liquid diet and advanced as tolerated
• CT-guided percutaneous drainage
• Surgical intervention:
  • Hinchey’s stage III or IV
  • Complications
  • Inability to rule out carcinoma
  • Failure of medical therapy

Colonic volvulus

Definition & Types

• Derived from the Latin word volvere (“to twist”).
• Part of the colon twists on its mesentery, resulting in colonic obstruction.
• The main types:
  • Sigmoid volvulus (counterclockwise)
    • in canary
  • Cecal volvulus (clockwise direction)
    • in young
    • Important in antiviral
    • by colonoscopy

Sigmoid vs Cecal Volvulus

Definition

• Sigmoid volvulus is the twisting of the sigmoid colon of the large intestine.
• Cecal volvulus takes place due to the torsion caused in the cecum area

Extension of the Volvulus

• Sigmoid volvulus can only move upwards and goes to the right upper quadrant.
• Cecal volvulus can move in any direction and can be observed in the pelvic area as well.
• at any direction

Affected Population

• The elderly population is mostly affected by sigmoid volvulus.
• The young population is mostly affected by cecal volvulus.

Causes

• High residue diet
• Bulky stool
• Chronic constipation
• Laxatives abuse
• Organic/ Anatomical:
  • Tortious elongated colon
  • Adhesive band
  • Overloaded colon
  • Long mesocolon
  • Narrow colonic attachment

Management

• In patients with no evidence of peritonitis or ischemic bowel
• Resuscitation
• Detorsion:
  • Sigmoid volvulus (success rate 90%)
    • Sigmoidoscopy or Colonoscopy
    • Rectal tube placement
  • Cecal volvulus (success rate 15-20)
    • Cecostomy
• Surgery:
  • if record or details
  • Open vs Lap
  • Sigmoid resection/ Hartman’s (Sigmoid)
  • Right hemicolectomy (Cecal)
  • Cecopexy alone is associated with volvulus recurrence in 20-30% of patients
  • Function
  • Unstable patient: surgery

Colostomies

Definition

• Stomas are artificial opening to connect a body cavity to the outside
• Named according to anatomic location (Colostomy, Ileostomy..)
• A colostomy is a surgical procedure where a portion of the large intestine is brought through the abdominal wall to carry stool out of the body.
  • Temporary vs. Permanent
  • Emergency vs. Elective

Types of Colostomies

1. Loop Colostomy

• Proximal and the distal limbs are opened into the common opening
• Two opening in one stoma, with
• Artificial devise between the openings, to keep bowel from slipping back
• Transverse colon/ Sigmoid colon
• Typically temporary, and an emergency procedure

2. Double Barrel Colostomy

• Two opening
• Proximal opening is functional, but distal one as mucous fistula
• Temporary or permanent

3. End Colostomy

• Created from the proximal end of the colon
• Distal end remains as a blind pouch, or it can be exteriorized separately
• Hartmann procedure:
  • Proximal end colostomy
  • Distal end of colon closed.

Indications

• To relieve distal obstruction
• Colorectal carcinoma
• Large bowel obstruction
• Protection of distal anastomosis
• Traumatic perineal injury
• High anal fistulae
• Diverticular disease/ IBD
• Ischemia
• Congenital anomalies (Hirschsprung’s disease, Meconium ileus, Imperforate anus)

Complications (+ Nutritional Complication)

• Edema/ Prolapsed
• Necrosis/ Ischemia
• Retraction
• Bleeding
• Obstruction
• Wound infection
• Leakage
• Stenosis
• Parastomal hernia
• Related to output (Metabolic/ hydration)

Surgery 1

Large bowel obstruction

• It is an emergency condition that requires early identification and intervention.
• Acute Vs chronic
• Complete vs Partial
• Mechanical vs pseudo-obstruction

Symptoms:

• Crampy abdominal pain
• Abdominal distention
• Nausea and vomiting

Other symptoms that may be diagnostically significant include the following:

• Abrupt onset of symptoms (acute obstruction)
• Recurrent left lower quadrant abdominal pain over several years (suggestive of diverticulitis, a diverticular stricture)
• Chronic constipation, long-term cathartic use, and straining at stools (diverticulitis or carcinoma)
• Changes in stool caliber (suggestive of carcinoma)

Signs:

• Abdomen (inspection, auscultation, percussion, and palpation)
• Evaluate bowel sounds, tenderness, rigidity, guarding, and any mass or fullness
• Inguinal and femoral regions, look for a possible incarcerated hernia
• Rectum, contents of anal vault, and stool consistency; perform fecal occult blood testing as appropriate

Etiology:

• Neoplasm* (benign or malignant) 60%
• Stricture (diverticular or ischemic)
• Volvulus (colonic, sigmoid, cecal) 5%
• Fecal Impaction

Diagnosis

Labs:

• Complete blood count (CBC) : WBC, HB, Hematocrit
• Coagulation
• Electrolytes
• LFT
• Serum lactate (if bowel ischemia is a consideration)
• Urinalysis
• Stool guaiac test

Diagnosis

Radiology Imaging

• Plain radiography (flat and upright)
• Contrast radiography with enema

Computed tomography (CT) –

• This is the imaging modality of choice

Colonoscopy/Bx

Management

Initial therapy

• Volume resuscitation
• Appropriate preoperative broad-spectrum antibiotics
• Timely surgical consultation
• Consideration of a nasogastric tube for severe colonic distention and vomiting

The following are emergencies that call for surgical intervention:

• Closed loop obstructions

• Sepsis due to complicated diverticular disease
• Bowel ischemia
• Volvulus

Supportive measures:

• Nil By Mouth
• Intake- output charts
• IV lines, and rehydration (IV crystalloid with K+)
• Foley’s catheter
• NG Tube to aspirate content for ‘decompression’
• TED stockings, DVT prophylaxis
• Antibiotics
• Antiemetics
• Analgesia

Surgery:

Closed loop obstructions, Sepsis, Bowel ischemia, Volvulus