Bowel obstruction is a partial or complete blockage of the intestines. This blockage prevents digestive materials from passing normally through the body’s small or large bowel. Bowel obstruction can range from mild to severe. Any case of bowel obstruction requires immediate medical treatment to determine the severity. Failure to treat a bowel obstruction may result in intestinal damage and death.
Types of Bowel Obstruction
There are two primary sections of the bowel: the small bowel and the large bowel. The bowel is roughly 30 feet long and begins after the stomach. It exists to digest food, absorb water and nutrients, and eliminate remaining waste from the body. A bowel obstruction can take place in either the small or large bowel. It can be functional or mechanical.
Small Bowel Obstruction
The small bowel, or small intestine, is composed of roughly 25 feet of coiled hollow tube, also called a tract. It includes the duodenum, jejunum, and ilium. The small bowel is connected to the stomach via the duodenum and leads directly to the large bowel. It is where a majority of digestion and food absorption takes place. Roughly 5.5% of small bowel obstructions are fatal if not properly treated.
Large Bowel Obstruction
The large bowel, or large intestine, is the last section of the digestive system. It consists of the cecum, colon, rectum, and anal canal. The large bowel is roughly 4.9 feet long, or one-fifth of the entire intestinal canal. The primary function of the large bowel is to absorb water that remains from indigestible food and pass the remaining waste through the body.
Functional Bowel Obstruction
A functional bowel obstruction occurs when the bowel ceases its normal function. Causes of functional bowel obstruction include electrolyte abnormalities, illnesses such as blood clots or kidney stones, and medications such as muscle relaxants. This type of bowel obstruction is typically less serious or complete than mechanical bowel obstruction.
Mechanical Bowel Obstruction
Mechanical bowel obstruction is typically caused by masses in the bowel that block the passageway and prevent normal function. This type of bowel obstruction also includes sites where the bowel has twisted and sites that are scarred due to infection, prior surgery, or congenital abnormality. Mechanical bowel obstruction is a potentially fatal if left untreated.
Causes of Bowel Obstruction
Small bowel obstruction is often caused by:
- Crohn’s disease
- Adhesions from previous surgery
- Volvulus, or the twisting of the bowel on itself
- Ischemic strictures causing blood supply restriction
- Foreign bodies, such as gallstones or swallowed objects
- Neoplasms, or abnormal masses due to excessive cell growth
Large bowel obstruction causes can include:
- Fecal impaction
- Endometriosis in women
- Inflammatory bowel disease
- Adhesions from previous surgery
Signs and Symptoms
Indications of bowel obstruction may involve:
- Fecal vomiting
- Excessive gas
- Abdominal pain
- Abdominal distension
Complications of Bowel Obstruction
Bowel obstruction is a medical emergency that requires proper diagnosis and immediate treatment. Some cases of bowel obstruction resolve naturally, particularly during partial obstruction. However, operative treatment is usually required depending on the severity of the bowel obstruction. Patients should be carefully monitored and examined several times a day to ensure that the condition does not worsen.
If left untreated, a bowel obstruction may cause ischemia, or inflammation and injury due to inadequate blood supply. This can lead to death of the associated bowel tissue, which must then be surgically removed. Severe ischemia can lead to bowel perforation and the subsequent onset of sepsis. Sepsis is a potentially fatal condition during which the body enters a state of shock in response to infection. In cases of bowel ischemia, the mortality rate has reached 30%.