Bowel sounds, absent [Silent abdomen]

Absent bowel sounds refers to an inability to hear any bowel sounds with a stethoscope in any quadrant after listening for at least 5 minutes in each quadrant. Bowel sounds cease when mechanical or vascular obstruction or neurogenic inhibition halts peristalsis. When peristalsis stops, gas from bowel contents and fluid secreted from the intestinal walls accumulate and distend the lumen, leading to life-threatening complications (such as perforation, peritonitis, and sepsis) or hypovolemic shock.

Simple mechanical obstruction, resulting from adhesions, hernia, or tumor, causes loss of fluids and electrolytes and induces dehydration. Vascular obstruction cuts off circulation to the intestinal walls, leading to ischemia, necrosis, and shock. Neurogenic inhibition, affecting innervation of the intestinal wall, may result from infection, bowel distention, or trauma. It may also follow mechanical or vascular obstruction or metabolic derangement such as hypokalemia.

Abrupt cessation of bowel sounds, when accompanied by abdominal pain, rigidity, and distention, signals a life-threatening crisis requiring immediate intervention. Absent bowel sounds following a period of hyperactive sounds are equally ominous and may indicate strangulation of a mechanically obstructed bowel.

Action stat!

If you fail to detect bowel sounds and the patient reports sudden, severe abdominal pain and cramping or exhibits severe abdominal distention, prepare to insert a nasogastric (NG) or intestinal tube to suction lumen contents and decompress the bowel. (See Are bowel sounds really absent? page 88.) Administer I.V. fluids and electrolytes to offset dehydration and imbalances caused by the dysfunctioning bowel.

Because the patient may require surgery to relieve an obstruction, withhold food and fluids. Take the patient's vital signs, and be alert for signs of shock, such as hypotension, tachycardia, and cool, clammy skin. Measure abdominal girth as a baseline for gauging subsequent changes. If the patient vomits, be sure to check it for occult blood.

History and physical examination

If the patient's condition permits, proceed with a brief history. Start with abdominal pain: When did it begin? Has it gotten worse? Where does he feel it? Ask about a sensation of bloating and about flatulence. Find out if the patient has had diarrhea or has passed pencil-thin stools—possible signs of a developing luminal obstruction. The patient may have had no bowel movements at all—a possible sign of complete obstruction or paralytic ileus.

Ask about conditions that commonly lead to mechanical obstruction, such as abdominal tumors, hernias, and adhesions from past surgery. Determine if the patient was involved in an accident—even a seemingly minor one, such as falling off a stepladder—that may have caused vascular clots. Check for a history of acute pancreatitis, diverticulitis, or gynecologic infection, which may have led to intra-abdominal infection and bowel dysfunction. Be sure to ask about previous toxic conditions, such as uremia, and about spinal cord injury, which can lead to paralytic ileus.

If the patient's pain isn't severe or accompanied by other life-threatening signs or symptoms, obtain a detailed medical and surgical history and perform a complete physical examination followed by an abdominal assessment and pelvic examination.

Start your assessment by inspecting the abdominal contour. Stoop at the recumbent patient's side and then at the foot of his bed to detect localized or generalized distention. Auscultate for bowel sounds in all quadrants, listening for 5 minutes in each quadrant. Percuss and palpate the abdomen gently. Listen for dullness over fluid-filled areas and tympany over pockets of gas. Palpate for abdominal rigidity and guarding, which suggest peritoneal irritation that can lead to paralytic ileus.

Medical causes

Complete mechanical intestinal
obstruction.Absent bowel sounds follow a period of hyperactive bowel sounds in this potentially life-threatening disorder. This silence accompanies acute, colicky abdominal pain that arises in the quadrant of obstruction and may radiate to the flank or lumbar regions. Associated signs and symptoms include abdominal distention, and bloating, constipation, and nausea and vomiting (the higher the blockage, the earlier and more severe the vomiting). In late stages, signs of shock may occur with fever, rebound tenderness, and abdominal rigidity.

Mesenteric artery occlusion.With mesenteric artery occlusion, a life-threatening disorder, bowel sounds disappear after a brief period of hyperactive sounds. Sudden, severe midepigastric or periumbilical pain occurs next, followed by abdominal distention, bruits, vomiting, constipation, and signs of shock. Fever is common. Abdominal rigidity may appear later.

Paralytic (adynamic) ileus.The cardinal sign of paralytic (adynamic) ileus is absent bowel sounds. In addition to abdominal distention, associated signs and symptoms include generalized discomfort and constipation or the passage of small, liquid stools. If paralytic ileus follows acute abdominal infection, the patient may also experience fever and abdominal pain.

Other causes

Abdominal surgery.Bowel sounds are normally absent after abdominal surgery—the result of anesthetic use and surgical manipulation.

Nursing considerations

▪ After NG or intestinal tube insertion, elevate the head of the bed at least 30 degrees.

▪ Ensure tube patency by checking for drainage and properly functioning suction devices, and irrigate accordingly.

▪ Administer I.V. fluids and electrolytes and monitor laboratory values, as indicated.

▪ Prepare the patient for X-ray and imaging studies and blood work to determine the cause of absent bowel sounds.

▪ Administer analgesics, as ordered.

▪ Withhold food and fluids, as indicated.

Patient teaching

▪ Explain diagnostic tests and therapeutic procedures.

▪ Discuss any food or fluid restrictions.

▪ Explain the need for postoperative ambulation.

▪ Teach the patient about the cause of absent bowel sounds and the treatment plan after the diagnosis is established.

Pictures

Book Source Details

• Book Title: Nursing: Interpreting Signs and Symptoms
• Author(s): Springhouse
• Year of Publication: 2007
• Copyright Details: Nursing: Interpreting Signs and Symptoms, Copyright © 2007 Lippincott Williams & Wilkins.

Other Book Chapters Related to Digestive symptoms

Read excerpts from these other book chapters related to Digestive symptoms:

Copyright Details: Nursing: Interpreting Signs and Symptoms, Copyright © 2008 Williams & Wilkins.

More About Causes of Digestive symptoms

• Back to symptom: Digestive symptoms: Introduction (review 4397 causes)
• Next Book Extract About Digestive symptoms: CONSTIPATION (Differential Diagnosis in Primary Care)
• All Book Extracts: All Online Book Extracts for Digestive symptoms

More About This Book: Title: Nursing: Interpreting Signs and Symptoms Authors: Springhouse Publisher: Lippincott Williams & Wilkins Copyright: 2007 ISBN: 1-58255-668-7

 » Next page: CONSTIPATION (Differential Diagnosis in Primary Care)

Rate This Website

What do you think about the features of this website? Take our user survey and have your say:

Website User Survey

Medical Tools & Articles:

Next articles:

• CONSTIPATION (Differential Diagnosis in Primary Care)
• NAUSEA AND VOMITING (Differential Diagnosis in Primary Care)
• Medications causing Digestive symptoms
• Videos relating to Digestive symptoms
• Drug interactions causing Digestive symptoms

Tools & Services:

• Bookmark this page
• Take a survey relating to Digestive symptoms
• Symptom Search
• Symptom Checker
• Medical Dictionary
• Give your feedback

Medical Articles:

• Disease & Treatments Search
• Misdiagnosis Center
• Full list of interesting articles

Forums & Message Boards

• Ask or answer a question at the Boards:
• I cannot get a diagnosis. Please help.
• Tell us your medical story.
• Share your misdiagnosis story.
• What is the best treatment for my condition?
• See all the Boards.

Enter your search terms Submit search form
Search The Web Search wrongdiagnosis.com

Common Health Mistakes

Symptom
Checker

Search Specialists by State and City