Large Bowel Obstruction

Large Bowel Obstruction

Laura Lynn Beck, MD and David Ray Velez, MD

Table of Contents

Definitions
Etiology
Presentation and Diagnosis
Management

See Also:
*See Small Bowel Obstruction (SBO)
*See Acute Colonic Pseudoobstruction (Ogilvie’s Syndrome)
*See Colon Cancer

Definitions

Large Bowel Obstruction (LBO): Interruption of the Normal Flow of Intraluminal Contents Through the Colon

Etiology

  • Functional Obstruction: Obstruction Due to Dysfunctional Peristalsis
    • Due to Paralytic Ileus or Acute Colonic Pseudoobstruction (Ogilvie Syndrome)
  • Mechanical Obstruction: Obstruction Due to Intrinsic or Extrinsic Compression

In Practice, the Term “Large Bowel Obstruction” Typically Refers to a Mechanical Obstruction Although Function Obstruction May Also Be Included

Completeness

  • Partial Obstruction: Some Gas or Liquid Stool is Able to Pass the Obstruction
  • Complete Obstruction: Nothing is Able to Pass the Site of Obstruction

Closed Loop Obstruction: Both the Proximal and Distal Ends are Obstructed

  • No Outlets are Available for Decompression
  • Rapid Progression with High Risk for Strangulation and Perforation

Accounts for 10-15% of All Intestinal Obstructions with a Higher Morbidity and Mortality than Small Bowel Obstruction (SBO)

Etiology

Malignancy is the Most Common Cause (60%) of Large Bowel Obstruction

  • Colonic Adenocarcinoma is Most Common
  • Left-Sided Tumors are More Likely to Obstruct Due to the Smaller Caliber Lumen
  • Large Bowel Obstruction is the Initial Presenting Symptom in 30% of Colorectal Cancers
  • *See Colon Cancer

Benign Causes

  • Volvulus – The Most Common Benign Cause (15-20%)
  • Hernia
  • Adhesions
  • Stricture
  • Diverticular Disease
  • Intussusception
  • Endometriosis
  • Foreign Body
  • Gallstone Ileus
  • Bezoar
  • Tuberculosis
  • Fecal Impaction/Severe Constipation
  • Retroperitoneal Fibrosis
  • Advanced Pelvic Malignancy Causing Extrinsic Compression

Functional Causes

Presentation and Diagnosis

Presentation

  • Nausea and Vomiting
    • Risk for Aspiration
    • May Be Feculent
  • Abdominal Distention
  • Abdominal Pain
  • Obstipation (Unable to Pass Flatus or Stool)

Large Bowel Obstruction (LBO) Often Has More Constant Pain with Feculent Emesis and More Significant Distention than Small Bowel Obstruction (SBO)

Diagnosis

  • Diagnosis is Generally Made by Abdominal Imaging
  • Computed Tomography (CT)
    • Generally the Preferred Diagnostic Study
    • Greater Sensitivity and Specificity than Plain Films
    • Better at Characterizing the Obstruction and Evaluating for Bowel Compromise
    • Can Also Evaluate for Metastatic Disease
  • Abdominal Plain Film
    • Generally Nonspecific and Even Classic Volvulus Findings are Generally Not Reliable on Plain Film XR
  • Endoscopy
    • Generally Not Necessary in the Diagnosis of Large Bowel Obstruction Itself but May Be Used in the Management or Evaluation of Malignancy

Staging and General Oncologic Evaluation Includes Baseline CEA with CT Abdomen/Pelvis and CT Chest

Management

Initial Management

  • Bowel Rest
  • Fluid Resuscitation
  • Correct Electrolyte Disturbances
  • Nasogastric (NG) Tube Decompression if Having Nausea/Vomiting

The Majority of Large Bowel Obstructions (75%) Will Require Surgical Intervention During the Same Hospital Stay, Unlike Small Bowel Obstructions (SBO) Which are Generally Managed Nonoperatively

Indications for Emergent Surgical Intervention

  • Hemodynamically Unstable
  • Bowel Ischemia or Strangulation
  • Perforation
  • Peritonitis
  • Closed Loop (Complete Obstruction with a Competent Ileocecal Valve)

Severe Symptoms is Also an Indication for Surgical Intervention During the Same Hospital Stay After Medical Optimization

Malignant Obstruction

  • *See Colon Cancer
  • Immediate Surgery Required: Oncologic Resection is Generally Preferred if Able
    • Oncologic Resection Includes ≥ 5 cm Margins with ≥ 12 Lymph Nodes for Complete Mesocolic Excision
    • Consider Primary Anastomosis vs Proximal Diversion Depending on Location and Condition
    • Diverting Loop Colostomy Alone is Performed for Advanced Disease if the Lesion is Unresectable or There is Known Significant Metastatic Disease to Rapidly Relieve Symptoms and Minimize the Morbidity and Delay to Chemotherapy
  • Immediate Surgery Not Required: Consider Endoscopic Stenting to Serve as a Bridge to a Delayed Elective One-Stage Definitive Resection
    • Consider Palliative Chemoradiation with or without a Diverting Loop Ostomy if Stenting is Not Feasible and Not a Candidate for Curative Resection
  • Rectal Mass: Diverting Transverse Loop Colostomy
    • Follow with Tissue Diagnosis, Staging CT/MRI, Colonoscopic Clearance, and Possible Neoadjuvant Chemoradiation Prior to Definitive Resection
    • Immediate Surgical Resection Generally Not Recommended for Obstructing Rectal Masses Prior to Outpatient Oncologic Evaluation
    • Endoscopic Stenting is Generally Not Recommended for Rectal Masses

Colectomy Extent if Concerned for Malignancy

  • Cecum/Ascending Colon Tumor: Right Hemicolectomy
  • Hepatic Flexure Tumor: Extended Right Hemicolectomy
  • Transverse Colon Tumor: Transverse Colectomy (Including Hepatic/Splenic Flexures)
  • Splenic Flexure Tumor: Extended Left Hemicolectomy
  • Descending Colon Tumor: Left Hemicolectomy
    • Consider Extension Past the Sigmoid if Distal
  • Sigmoid Colon Tumor: Sigmoidectomy
    • Consider Radical Left Hemicolectomy Including the Sigmoid if Proximal

Colonic Volvulus

Diverticular Disease

  • Malignancy Cannot Be Definitively Excluded in the Majority of These Scenarios Until Pathology is Complete
  • Generally Requires Surgical Resection vs Proximal Diversion for Diverticular Disease Causing Obstruction
  • Endoscopic Stenting is Not Beneficial in Diverticular Disease