Fecal Impaction

Alternative names: Impaction of the bowels

Fecal Impaction is an extreme form of constipation in which the contents of the colon become hard and dry, creating a blockage and making it impossible to have a bowel movement.  As a result, the contents of the intestines become backed up, leading to potentially serious complications if left untreated.

Once fecal impaction occurs, the colon is unable move the contents of the intestines through the body using its normal contraction process, peristalsis.

Causes and Development; Contributing Risk Factors

The main cause of fecal impaction is constipation.  It is often seen in those with chronic constipation who have been using laxatives; impaction becomes more likely when laxative use is stopped.

Risk factors include

• a sedentary lifestyle
• diseases of the brain or nervous system that block signals to the intestinal muscles

• certain drugs

  • anticholinergics affect the nerves and muscles of the bowel
  • antidiarrheal medicines, when overused
  • narcotic pain medication, such as methadone or codeine

Signs and Symptoms

The symptoms of fecal impaction include:

• chronic constipation
• leakage of watery stool or liquid
• abdominal discomfort
• abdominal bloating
• abdominal pain and cramping
• straining when trying to pass stools; feeling the need to push
• nausea
• vomiting
• headache
• unexplained weight loss
• weak appetite
• hardened areas or masses in the abdomen

Symptoms of severe fecal impaction include:

• rapid heart rate
• dehydration
• rapid breathing
• fever
• confusion
• easily becoming agitated
• bladder pressure
• urinary incontinence
• rectal bleeding
• blood in the stool
• lower back pain

Diagnosis and Tests

Diagnosis involves a physical examination and digital rectal exam (DRE) to check for hardened abdominal mass(es) in the abdomen and colon.  Once fecal impaction is suspected, an ultrasound, sigmoidoscopy or barium enema may be used to obtain a better view of the colon and rectum.

Treatment and Prevention

Laxatives are usually the first mode of treatment.  A warm mineral oil enema is often used to lubricate the stool.  If those don't work, it becomes necessary for a doctor to manually break up the mass and remove feces from the colon with a gloved hand.  If that doesn't work then an enema or water irrigation may be used.  In rare cases, surgery is required.

The best way to prevent fecal impaction is to avoid constipation.  Drinking plenty of water, eating fiber-rich foods, reducing sugar intake, and exercise are also good preventive measures.

Complications

An overly widened colon (megacolon) or complete blockage of the bowel requires emergency removal of the impaction.

Complications include hemorrhoids, rectal/anal tears, tissue death (necrosis), and tears in the colon wall, which are potentially very serious.