What Is Bowel Obstruction?
Bowel (intestinal) obstruction is a partial or complete mechanical blockage of the bowel. Typical symptoms are cramping abdominal pain, nausea, rumbling bowel sounds and cessation of gas. You can suspect bowel obstruction, if you have intestinal hernia, abdominal cancer, diverticulosis, other chronic bowel disease, history of abdominal surgery, or you have ingested a “foreign object”. Suspected bowel obstruction is an emergency; it can cause intestinal gangrene in as little as six hours, or death in a couple of days.
Bowel paralysis (often after abdominal surgery) without mechanical obstruction is called ileus.
Small Bowel Obstruction (SBO) – Causes and Symptoms
Main causes of small bowel obstruction include:
- Adhesions after abdominal surgery or radiotherapy, causing chronic intermittent (come and go) abdominal pain
- Malignant abdominal tumors
- Intestinal hernia
- Crohn’s disease
- Trapped gallstones
- Cramping pain in the middle or upper abdomen
- Nausea and vomiting
- Rumbling bowel sounds that fade after some hours
- Abdomen may be tender to touch
- Diarrhea (early symptom) or constipation (late symptom)
- Fever and rapid heart beat (late symptoms, especially in complications)
Large Bowel Obstruction (LBO) – Causes and Symptoms
- Colorectal cancer
- Fecal impaction due to hardened stool (common in bedridden patients or chronically constipated people who take antacids containing calcium carbohydrate)
- Volvulus - twisting of the colon around its axis (in infants and toddlers)
- Cramping pain in the lower left abdomen
- Distension of the lower abdomen
- Nausea (sometimes vomiting)
- Rumbling bowel sounds
- History of narrow stools (in rectal cancer) and chronic constipation
Partial and Complete Bowel Obstruction
In partial bowel obstruction, the passage of the bowel content is hampered, but not completely blocked. Partial obstruction develops slowly (weeks, months); typical example is a slowly growing rectal cancer resulting in chronic constipation and thin stools.
Complete bowel obstruction is common in small intestinal hernia. It is often accompanied with intestinal strangulation (see below). Impacted stool can cause complete obstruction of the large bowel.
Complications of Bowel Obstruction
Complications mostly occur in complete bowel obstruction:
- Aspiration (swallowing of vomit) resulting in aspiration pneumonia
- Strangulation – twisted bowel with blocked arteries regularly resulting in intestinal gangrene if not treated promptly
- Sepsis – spread of infection into the blood
- Intestinal perforation resulting in peritonitis
Doctor can suspect intestinal obstruction from symptoms and physical examination, but one of the following investigation is needed for diagnosis:
- X-ray usually shows trapped gas and fluid in the form of “air-fluid levels” in the intestinal loops above obstruction (Picture 1). Contrast X-ray with barium can reveal an exact site of obstruction.
- CTcan show abdominal mass or adhesions.
- Abdominal ultrasound can often exclude bowel obstruction.
- Colonoscopy or sigmoidoscopy can reveal and often at least partially resolve large bowel obstruction.
Picture 1: X-ray revealing small bowel obstruction.
Note air-fluid levels (dark half-circles).
Disorders Mimicking Intestinal Obstruction
The following abdominal disorders may mimic intestinal obstruction:
- Severe abdominal bloating from any cause
- Severe constipation
- Food poisoning
- Gallbladder disorders
- Acute pancreatitis or pancreatic cancer
- Acute appendicitis
- Slow gastric emptying (gastroparesis)
- Urinary infection
- Blood clot in intestinal arteries causing acute ischemic colitis
- In women: abdominal or pelvic adhesions, abortion, ovarian cancer or torsion, painful menstruation, endometriosis, pelvic inflammatory disease
Irritable bowel syndrome (IBS) is not likely to mimic intestinal obstruction.
Treatment of Bowel Obstruction
Intestinal obstruction usually requires hospitalization. Prognosis is good, if treatment starts early. On the other hand, severe untreated bowel obstruction with strangulation regularly ends with death.
In small bowel obstruction, treatment is often non-surgical. Intravenous fluid and nutrients, suction of accumulated fluid from the bowel through a tube inserted through the nose into the bowel (nasogastric tube), painkillers and antibiotics are usually needed. In large bowel obstruction and in children, surgery is commonly required.
Postoperative abdominal adhesions can be often treated with laparoscopy.
Impacted stool can be removed manually or with enema.
Bowel obstruction recovery time completely depends on the cause and treatment procedure.
Diet and Home Remedies in Intestinal Obstruction
There is no diet or home remedies that would treat bowel obstruction. High-fiber diet (fiber supplements, if necessary), drinking enough fluid, active life style and avoiding unnecessary stress are recommended to preventconstipation and diverticulosis.
Regular colonoscopy after age of 40 is recommended, if you have a family history of colorectal cancer.
- Acute Severe Abdominal Pain
- Causes of Abdominal Pain
- Abdominal and Pelvic Adhesions
- Constipation – Causes and Treatment
Article reviewed by Dr. Greg. Last updated on April 12, 2011