Bowel sounds

Alternative names 
Abdominal sounds

Definition
Abdominal sounds are the noises made by the intestines.

Considerations

Abdominal sounds (bowel sounds) are made by the movement of the intestines as they push food through. Since the intestines are hollow, bowel sounds can echo throughout the abdomen much like the sounds heard from water-pipes.

The majority of the bowel sounds are harmless and simply indicate that the gastrointestinal tract is working. Abdominal sounds are evaluated by listening to the abdomen with a stethoscope (auscultation).

While the majority of bowel sounds are normal, there are some instances where abnormal bowel sounds provide valuable information about the health of the body.

Ileus is a condition in which the examiner is unable to hear any bowel sounds when listening to the abdomen. This indicates a lack of intestinal activity. Many medical conditions may lead to this but it is important to evaluate it further because gas, secretions, and intestinal contents can accumulate and rupture the bowel wall.

Reduced (hypoactive) bowel sounds include a reduction in the loudness, tone, or regularity of the bowel sounds. They indicate a slowing of intestinal activity. Hypoactive bowel sounds are normal during sleep, and also occur normally for a short time after the use of certain medications and after abdominal surgery. Decreased or absent bowel sounds often indicates constipation.

Increased (hyperactive) bowel sounds are sometimes heard even without a stethoscope. Hyperactive bowel sounds reflect an increase in intestinal activity. This can sometimes occur with diarrhea and after eating.

Abdominal sounds are always evaluated in conjunction with symptoms such as nausea, vomiting, presence or absence of bowel movements, or gas. If bowel sounds are hypoactive or hyperactive, along with abnormal symptoms, continued evaluation by a health care provider is important.

For example, absent bowel sounds after a period of hyperactive bowel sounds are significant and can indicate that rupture of the intestines, or strangulation of the bowel with subsequent death (necrosis) of the bowel tissue may have occurred.

Common Causes

Most of the sounds you hear your stomach and intestines make are due to normal digestion and are no need for concern. However, if other troubling symptoms occur, a doctor can use a stethoscope to listen to abdominal sounds and determine if there is a problem.

Many conditions may cause hyperactive or hypoactive bowel sounds. Most are harmless and require no treatment. However, the following are a list of more serious conditions that can cause abnormal bowel sounds.

Hyperactive, hypoactive, or absent bowel sounds:

     
  • mechanical bowel obstruction (caused by hernia, tumor, adhesions, or similar conditions that can physically block the intestines)  
  • blood vessel obstruction and its resulting tissue damage (for example, blood clots can cause mesenteric artery occlusion, which prevents the intestines from obtaining a proper blood flow)  
  • paralytic ileus, a problem with the nerves to the intestines (reduced nerve activity can result from infection, overdistended bowel, trauma, bowel obstruction, vascular obstruction, and chemical imbalances such as hypokalemia).

Hypoactive bowel sounds (other causes):

     
  • drugs that reduce intestinal movements, including opiates (such as codeine), anticholinergics, phenothiazines, and others  
  • general anesthesia and spinal anesthesia  
  • irradiation of the abdomen (radiation therapy for cancer)  
  • surgery in the abdomen (may cause reduced bowel sounds for 1 to 5 days)

Hyperactive bowel sounds (other causes):

     
  • diarrhea (from any cause including emotional stress)  
  • Crohn’s disease  
  • GI bleeding  
  • ulcerative colitis  
  • food allergy  
  • infectious enteritis

Call your health care provider if

Call your health care provider if you experience any symptoms such as nausea, vomiting, prolonged diarrhea or constipation, bleeding from your rectum, or any other symptoms that are not normal for you.

What to expect at your health care provider’s office
The medical history will be obtained and a physical examination performed. Medical history questions concerning abdominal sounds may include:

     
  • What other symptoms are also present?  
  • Have you noticed any abdominal pain?  
  • Have you noticed any diarrhea?  
  • Have you noticed any constipation?  
  • Have you noticed any abdominal distention?  
  • Have you noticed any excessive or absent gas (flatus)?  
  • Have you noticed any bleeding from the rectum or black stools?

For physical examination, temperature, pulse, respiratory rate, and blood pressure are checked. Careful abdominal examination will be performed. Examination with a stethoscope may reveal abnormal bowel sounds which may have gone unnoticed by the patient. Diagnostic tests to determine the cause may include:

     
  • various blood tests  
  • abdominal X-ray  
  • abdominal cat scan  
  • endoscopy  
  • other imaging studies and tests

While many conditions are managed in a health care provider’s office, if there are signs of an actual or impending emergency, hospitalization may be necessary. Measures may be taken to empty the bowel. This is done by placing a tube through the nose or mouth into the stomach or intestines (nasogastric tube) and suctioning the intestinal contents out.

Usually no fluids or food should be taken by mouth, to allow the intestines to rest. Intravenous fluids are often needed. Medications may be given to reduce symptoms and to treat the cause (the specific medication depends on the situation). Surgery may be needed immediately in some cases.
If diagnosed and treated for a condition, you may want to add it to your personal medical record.

Johns Hopkins patient information

Last revised: December 4, 2012
by Amalia K. Gagarina, M.S., R.D.

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.