Medscape is available in 5 Language Editions – Choose your Edition here.


Large-Bowel Obstruction

  • Author: Christy Hopkins, MD, MPH; Chief Editor: Steven C Dronen, MD, FAAEM  more...
Updated: Dec 09, 2015

Practice Essentials

Large-bowel obstruction (LBO) is an emergency condition that requires early identification and intervention. It is important to distinguish colonic obstruction from ileus, as well as to differentiate between a true mechanical obstruction and a pseudo-obstruction; treatment differs. See the image below. 

Contrast study demonstrates colonic obstruction atContrast study demonstrates colonic obstruction at the level of the splenic flexure, in this case due to carcinoma. Radiograph courtesy of Charles J McCabe, MD†.

See Can't-Miss Gastrointestinal Diagnoses, a Critical Images slideshow, to help diagnose the potentially life-threatening conditions that present with gastrointestinal symptoms.

Signs and symptoms

A history of bowel movements, flatus, obstipation, and associated symptoms should be obtained. Complaints in patients with LBO may include the following:

  • Abdominal distention
  • Nausea and vomiting
  • Crampy abdominal pain

Other symptoms that may be diagnostically significant include the following:

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

Assessment of symptoms should attempt to distinguish the following:

  • Complete obstruction vs partial obstruction vs ileus
  • Colonic lesion development history
  • Obstruction secondary to intussusception
  • Obstruction secondary to acute colonic pseudo-obstruction (ACPO), or Ogilvie syndrome

Although a complete physical examination is necessary, the examination should place special emphasis on the following key areas:

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

See Presentation for more detail.


The following laboratory studies may be helpful:

  • Complete blood count (CBC)
  • Hematocrit
  • Prothrombin time (PT)
  • Type and crossmatch
  • Serum chemistries
  • Serum lactate (if bowel ischemia is a consideration)
  • Urinalysis
  • Stool guaiac test

Imaging modalities that may be considered are as follows:

  • Plain radiography (flat and upright)
  • Contrast radiography with enema
  • Computed tomography (CT) – This is the imaging modality of choice if a colonic obstruction is clinically suspected; contrast-enhanced CT can help distinguish between partial and complete obstruction, ileus, and small-bowel obstruction

See Workup for more detail.


Initial therapy in patients with suspected LBO includes the following:

  • 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
  • Bowel ischemia
  • Volvulus

Ileus is treated as follows:

  • Correction of fluid and electrolyte imbalances
  • Treatment of the underlying disorder
  • If the patient is vomiting, nasogastric decompression
  • Cessation of medications that slow colonic motility, if possible

Acute colonic pseudo-obstruction is treated as follows:

  • In the absence of perforation, conservative management (bowel rest, hydration, and management of underlying disorders) for the first 24 hours
  • If conservative management fails, neostigmine or colonoscopic decompression
  • For refractory cases or in the presence of perforation, surgical intervention

Volvulus is treated as follows:

  • For a sigmoid volvulus, in the absence of peritoneal signs, endoscopic reduction and decompression
  • For recurrence after decompression, surgical resection
  • For cecal or transverse colon volvulus, surgical resection and anastomosis; for poor surgical candidates, endoscopic detorsion and decompression

Intussusception is treated as follows:

  • Contrast enema (barium or air; much more likely to succeed in children than in adults)
  • If signs suggest peritonitis or perforation or contrast enema is unsuccessful, surgery

Colonic masses and strictures are treated as follows:

  • Endoscopic dilation and stenting of colonic obstruction (either as palliation or as preparation for surgical resection)
  • Surgery (left colon) – Resection without primary anastomosis or resection with primary anastomosis and intraoperative lavage
  • Surgery (right colon) – Right colectomy and primary anastomosis between the ileum and the transverse colon

Diverticular disease is treated as follows:

  • For persistent obstruction despite appropriate medical management, surgery
  • For recurrent disease, elective colonic resection

See Treatment and Medication for more detail.



Large-bowel obstruction (LBO) is an emergency condition that requires early identification and intervention. The etiology of this condition is age dependent, and it can result from either mechanical interruption of the flow of intestinal contents (see the following image) or by the dilation of the colon in the absence of an anatomic lesion (pseudo-obstruction). Causes include neoplasms, inflammatory processes (diverticulitis), strictures, fecal impaction or volvulus.

Abdominal (kidney-ureter-bladder [KUB]) film of a Abdominal (kidney-ureter-bladder [KUB]) film of a patient with obstipation. Dilatation of the colon is associated with large-bowel obstruction. Radiograph courtesy of Charles J McCabe, MD†.

It is important to distinguish colonic obstruction from ileus, and differentiate between a true mechanical obstruction and a pseudo-obstruction, as the treatment differs.[1]

Colonic obstruction is more common in elderly individuals, due to the higher incidence of neoplasms and other causative diseases in this population. In neonates, colonic obstruction may be caused by an imperforate anus or other anatomic abnormalities. Obstruction may also be secondary to meconium ileus. In the pediatric population, Hirschsprung disease can resemble colonic obstruction.

For patient education information, see Digestive Disorders Center as well as Constipation in Adults and Abdominal Pain in Adults.

See also Ogilvie Syndrome, Ileus, Constipation, Small Bowel Obstruction, and Intussusception.



The prevalence of mechanical large-bowel obstruction (LBO) increases with age as does its main causes, colon cancer and diverticulitis. Sigmoid volvulus and cecal volvulus are also potential causes of this disorder.[2]

Mechanical obstruction of the large bowel causes bowel dilatation above the obstruction, which in turn, causes mucosal edema and impaired venous and arterial blood flow to the bowel. Bowel edema and ischemia increase the mucosal permeability of the bowel, which can lead to bacterial translocation, systemic toxicity, dehydration, and electrolyte abnormalities. Bowel ischemia can lead to perforation, fecal soilage of the peritoneal cavity, and dead bowel.

In cases of closed loop obstructions, such as colonic obstruction in the presence of a closed ileocecal valve or incarcerated hernia, this process may be accelerated.

The pathophysiology of acute colonic pseudo-obstruction (ACPO), or Ogilvie syndrome, is not clear, but it is thought to result from an autonomic imbalance, which results from decreased parasympathetic tone or excessive sympathetic output.[1, 3] This condition usually occurs in the setting of a wide range of medical or surgical illnesses. If untreated, colonic ischemia or perforation can occur.

Acute colonic pseudo-obstruction is characterized by a loss of peristalsis and results in the accumulation of gas and fluid in the colon. The right colon and cecum are most commonly involved. The risk of perforation for acute colonic pseudo-obstruction ranges from 3% to 15%.[4]



Approximately 60% of mechanical large-bowel obstructions (LBOs) are caused by malignancies, 20% are caused by diverticular disease, and 5% are the result of colonic volvulus.[1, 5, 6] The most common causes of adult large-bowel obstruction are as follows:

  • Neoplasm (benign or malignant)
  • Stricture (diverticular or ischemic)
  • Volvulus (colonic, sigmoid, cecal)
  • Intussusception, usually with an identifiable anatomic abnormality in adults but not in children
  • Impaction or obstipation

Neoplasms and diverticular disease

Obstructions caused by tumors tend to have a gradual onset and result from tumor growth narrowing the colonic lumen.

Diverticulitis is associated with muscular hypertrophy of the colonic wall. Repetitive episodes of inflammation cause the colonic wall to become fibrotic and thickened, leading to luminal narrowing.


A colonic volvulus results when the colon twists on its mesentery, which impairs the venous drainage and arterial inflow. Symptoms of this condition are usually abrupt. The cecum and sigmoid colon are most commonly affected.

Volvulus typically occurs in elderly, debilitated individuals; patients living in an institutionalized setting; or patients with a history of chronic constipation.Volvulus may also be seen during pregnancy, most commonly occurring in the third trimester when the gravid uterus displaces the colon.[7]


Intussusception is primarily a pediatric disease; however, it is estimated that between 5% and 16% of all intussusceptions in the Western world occur in adults. Two thirds of adult intussusception cases are caused by tumors. Two main types of intussusception affect the large bowel: enterocolic and colocolic.

Enterocolic intussusceptions involve both the small bowel and the large bowel. These are composed of either ileocolic intussusceptions or ileocecal intussusceptions, depending on where the lead point is located.

Colocolic intussusceptions involve only the colon. They are classified as either colocolic or sigmoidorectal intussusceptions.

Acute colonic pseudo-obstruction/Ogilvie syndrome

Acute colonic pseudo-obstruction (ACPO), or Ogilvie syndrome, has many etiologies. ACPO is a functional obstruction; it is typically seen in elderly or debilitated patients who are hospitalized with severe medical or traumatic illnesses. Medications that decrease intestinal motility are also associated with this disorder. In a retrospective review of more than 1400 cases of ACPO, the most common predisposing conditions were operative and nonoperative trauma (11%), infections (10%), and cardiac disease (10-18%).[8, 9]



Mortality is determined by the patient's overall medical condition and the presence of any comorbidities that may influence the patients surgical risk. If large bowel obstruction is treated early, the outcome is generally good. Mortality rates are increased in patients who have developed bowel ischemia or perforation. After surgical decompression, the prognosis is determined by the underlying disease. In general, overall mortality rates for large bowel obstructions are 20%, which increases to 40% if there is colonic perforation.

The mortality rate for acute colonic pseudo-obstruction is 15% with early care; mortality increases to 36% if colonic ischemia or perforation develops.[4]


The morbidity and mortality of large-bowel obstruction are often related to the surgical procedure used to relieve the colonic obstruction and, in the long term, to the underlying disease that caused the obstruction. Thus, complications of large-bowel obstruction may include the following:

  • Perforation
  • Peritonitis from bowel perforation secondary to overstrenuous attempts at reduction of a volvulus or intussusception, or injudicious attempts to dilate or stent an unsuitable colonic obstruction
  • Sepsis –Seen more frequently in cases in which a delay in diagnosis or treatment occurred
  • Intra-abdominal abscess from anastomotic leakage
  • Pneumonia from aspiration during emesis
  • Dehydration
  • Electrolyte disturbance
  • Death
Contributor Information and Disclosures

Christy Hopkins, MD, MPH Associate Professor, Department of Surgery, University of Utah School of Medicine; Medical Director, Division of Emergency Medicine, University Health Care

Christy Hopkins, MD, MPH is a member of the following medical societies: American College of Emergency Physicians

Disclosure: Nothing to disclose.

Chief Editor

Steven C Dronen, MD, FAAEM Chair, Department of Emergency Medicine, LeConte Medical Center

Steven C Dronen, MD, FAAEM is a member of the following medical societies: American Academy of Emergency Medicine, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.


BS Anand, MD Professor, Department of Internal Medicine, Division of Gastroenterology, Baylor College of Medicine

BS Anand, MD is a member of the following medical societies: American Association for the Study of Liver Diseases, American College of Gastroenterology, American Gastroenterological Association, and American Society for Gastrointestinal Endoscopy

Disclosure: Nothing to disclose.

Marc D Basson, MD, PhD, MBA, FACS Professor, Chair, Department of Surgery, Assistant Dean for Faculty Development in Research, Michigan State University College of Human Medicine

Marc D Basson, MD, PhD, MBA, FACS is a member of the following medical societies: Alpha Omega Alpha, American College of Surgeons, American Gastroenterological Association, Phi Beta Kappa, and Sigma Xi

Disclosure: Nothing to disclose.

Julian Katz, MD Clinical Professor of Medicine, Drexel University College of Medicine

Julian Katz, MD is a member of the following medical societies: American College of Gastroenterology, American College of Physicians, American Gastroenterological Association, American Geriatrics Society, American Medical Association, American Society for Gastrointestinal Endoscopy, American Society of Law, Medicine & Ethics, American Trauma Society, Association of American Medical Colleges, and Physicians for Social Responsibility

Disclosure: Nothing to disclose.

Juan B Ochoa, MD Assistant Professor, Department of Surgery, University of Pittsburgh; Medical and Scientific Director, HCN, Nestle Healthcare Nutrition

Disclosure: Nothing to disclose.

Joseph J Sachter, MD, FACEP Consulting Staff, Department of Emergency Medicine, Muhlenberg Regional Medical Center

Joseph J Sachter, MD, FACEP is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, American College of Physician Executives, American Medical Association, and Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

  1. Kahi CJ, Rex DK. Bowel obstruction and pseudo-obstruction. Gastroenterol Clin North Am. 2003 Dec. 32(4):1229-47. [Medline].

  2. Yeh EL, McNamara RM. Abdominal pain. Clin Geriatr Med. 2007 May. 23(2):255-70, v. [Medline].

  3. Saunders MD. Acute colonic pseudoobstruction. Curr Gastroenterol Rep. 2004 Oct. 6(5):410-6. [Medline].

  4. Fazel A, Verne GN. New solutions to an old problem: acute colonic pseudo-obstruction. J Clin Gastroenterol. 2005 Jan. 39(1):17-20. [Medline].

  5. Dite P, Lata J, Novotny I. Intestinal obstruction and perforation--the role of the gastroenterologist. Dig Dis. 2003. 21(1):63-7. [Medline].

  6. Flasar MH, Goldberg E. Acute abdominal pain. Med Clin North Am. 2006 May. 90(3):481-503. [Medline].

  7. Rabinovici R, Simansky DA, Kaplan O, Mavor E, Manny J. Cecal volvulus. Dis Colon Rectum. 1990 Sep. 33(9):765-9. [Medline].

  8. De Giorgio R, Knowles CH. Acute colonic pseudo-obstruction. Br J Surg. 2009 Mar. 96(3):229-39. [Medline].

  9. Batke M, Cappell MS. Adynamic ileus and acute colonic pseudo-obstruction. Med Clin North Am. 2008 May. 92(3):649-70, ix. [Medline].

  10. Slam KD, Calkins S, Cason FD. LaPlace's law revisited: cecal perforation as an unusual presentation of pancreatic carcinoma. World J Surg Oncol. 2007 Feb 2. 5:14. [Medline]. [Full Text].

  11. Sakorafas GH, Peros G. Obstructing sigmoid cancer in a patient with a large, tender, non-reducible inguinal hernia: the obvious diagnosis is not always the correct one. Eur J Cancer Care (Engl). 2008 Jan. 17(1):72-3. [Medline].

  12. Jaffe T, Thompson WM. Large-bowel obstruction in the adult: classic radiographic and CT findings, etiology, and mimics. Radiology. 2015 Jun. 275(3):651-63. [Medline].

  13. Saunders MD, Kimmey MB. Systematic review: acute colonic pseudo-obstruction. Aliment Pharmacol Ther. 2005 Nov 15. 22(10):917-25. [Medline].

  14. Atukorale YN, Church JL, Hoggan BL, et al. Self-expanding metallic stents for the management of emergency malignant large bowel obstruction: a systematic review. J Gastrointest Surg. 2015 Oct 26. [Medline].

  15. Geraghty J, Sarkar S, Cox T, et al. Management of large bowel obstruction with self-expanding metal stents. A multicentre retrospective study of factors determining outcome. Colorectal Dis. 2014 Jun. 16 (6):476-83. [Medline].

  16. Xu YS, Song T, Guo YT, et al. Placement of the decompression tube as a bridge to surgery for acute malignant left-sided colonic obstruction. J Gastrointest Surg. 2015 Dec. 19 (12):2243-8. [Medline].

  17. Trompetas V. Emergency management of malignant acute left-sided colonic obstruction. Ann R Coll Surg Engl. 2008 Apr. 90(3):181-6. [Medline]. [Full Text].

  18. Deen KI, Madoff RD, Goldberg SM, Rothenberger DA. Surgical management of left colon obstruction: the University of Minnesota experience. J Am Coll Surg. 1998 Dec. 187(6):573-6. [Medline].

  19. Fan YB, Cheng YS, Chen NW, et al. Clinical application of self-expanding metallic stent in the management of acute left-sided colorectal malignant obstruction. World J Gastroenterol. 2006 Feb 7. 12(5):755-9. [Medline].

  20. Repici A, Adler DG, Gibbs CM, Malesci A, Preatoni P, Baron TH. Stenting of the proximal colon in patients with malignant large bowel obstruction: techniques and outcomes. Gastrointest Endosc. 2007 Nov. 66(5):940-4. [Medline].

  21. Ptok H, Meyer F, Marusch F, et al. Palliative stent implantation in the treatment of malignant colorectal obstruction. Surg Endosc. 2006 Jun. 20(6):909-14. [Medline].

  22. Boyle DJ, Thorn C, Saini A, et al. Predictive factors for successful colonic stenting in acute large-bowel obstruction: a 15-year cohort analysis. Dis Colon Rectum. 2015 Mar. 58 (3):358-62. [Medline].

  23. Takeyama H, Kitani K, Wakasa T, et al. Self-expanding metallic stent improves histopathologic edema compared with transanal drainage tube for malignant colorectal obstruction. Dig Endosc. 2015 Dec 3. [Medline].

  24. Boggs W. Surgery should be last resort for obstructed defecation with rectocele. Medscape Medical News. January 6, 2014. Available at Accessed: January 13, 2014.

  25. Hicks CW, Weinstein M, Wakamatsu M, Savitt L, Pulliam S, Bordeianou L. In patients with rectoceles and obstructed defecation syndrome, surgery should be the option of last resort. Surgery. 2014 Apr. 155(4):659-67. [Medline].

  26. Douglas D. Palliative surgery for malignant bowel obstruction problematic. Medscape Medical News. February 13, 2014. [Full Text].

  27. Paul Olson TJ, Pinkerton C, Brasel KJ, Schwarze ML. Palliative surgery for malignant bowel obstruction from carcinomatosis: a systematic review. JAMA Surg. 2014 Apr. 149(4):383-92. [Medline].

  28. Frago R, Ramirez E, Millan M, Kreisler E, del Valle E, Biondo S. Current management of acute malignant large bowel obstruction: a systematic review. Am J Surg. 2014 Jan. 207 (1):127-38. [Medline].

This chest radiograph demonstrates free air under the diaphragm, indicating bowel perforation in a patient with large-bowel obstruction. Radiograph courtesy of Charles J McCabe, MD†.
Abdominal (kidney-ureter-bladder [KUB]) film of a patient with obstipation. Dilatation of the colon is associated with large-bowel obstruction. Radiograph courtesy of Charles J McCabe, MD†.
Gastrografin study in a patient with obstipation reveals colonic obstruction at the rectosigmoid level. Radiograph courtesy of Charles J McCabe, MD†.
Contrast study demonstrates colonic obstruction at the level of the splenic flexure, in this case due to carcinoma. Radiograph courtesy of Charles J McCabe, MD†.
Abdominal (kidney-ureter-bladder [KUB]) radiograph depicting massive dilatation of the colon due to a cecal volvulus. Radiograph courtesy of Charles J McCabe, MD†.
Contrast study of patient with cecal volvulus. The column of contrast ends in a "bird's beak" at the level of the volvulus. Radiograph courtesy of Charles J McCabe, MD†.
Massive dilatation of the colon due to a sigmoid volvulus. Radiograph courtesy of Charles J McCabe, MD†.
All material on this website is protected by copyright, Copyright © 1994-2016 by WebMD LLC. This website also contains material copyrighted by 3rd parties.