From the Guidelines
Bowel sounds can be present or absent in intestinal blockage, depending on the location and severity of the obstruction, with hyperactive or absent bowel sounds being common presentations, as noted in the 2018 guidelines on colon and rectal cancer emergencies 1. In the context of intestinal blockage, the presence or absence of bowel sounds is not a definitive indicator of the condition. According to the 2018 guidelines, abdominal examination may show tenderness, abdominal distension, and hyperactive or absent bowel sounds 1. Key points to consider include:
- Hyperactive bowel sounds may be present in early or partial intestinal blockage as the intestine contracts to overcome the obstruction.
- Absent bowel sounds may occur as the obstruction progresses or becomes complete, due to intestinal muscle fatigue.
- The absence of bowel sounds, accompanied by symptoms such as abdominal pain, distension, nausea, vomiting, and inability to pass gas or stool, requires immediate medical attention.
- Assessment of bowel sounds alone is not sufficient to diagnose or rule out an intestinal blockage, and imaging studies such as X-rays or CT scans are typically needed for definitive diagnosis, as suggested by the guidelines 1. It is essential to consider the entire clinical presentation, including symptoms, physical examination findings, and laboratory results, to accurately diagnose and manage intestinal blockage.
From the Research
Bowel Sounds in Intestinal Blockage
- The presence of bowel sounds in intestinal blockage is a complex topic, and research findings are not entirely conclusive 2, 3, 4.
- A study published in the World Journal of Gastroenterology found that auscultation of bowel sounds is non-specific for diagnosing bowel obstruction, but differences in sound characteristics between large bowel and small bowel obstruction may help determine the likely site of obstruction 2.
- High-pitched bowel sounds are considered a classic finding in intestinal obstruction, along with abdominal distension, tympany to percussion, and cessation of passage of flatus and stool 4.
- However, another study found that there was no significant difference in sound-to-sound interval, dominant frequency, and peak frequency among patients with acute bowel obstruction, subacute bowel obstruction, and no bowel obstruction 2.
- The technique of auscultating bowel sounds has been evaluated, and the literature reveals conflicting information and a lack of available research on the topic, making it challenging to determine the clinical significance of auscultation findings 3.
Diagnostic Approaches
- Multidetector computed tomography (MDCT) is commonly used to diagnose bowel obstruction, focusing on confirming the obstruction, determining the transition point, establishing the cause, and seeking signs of complications 5.
- Sonographic evaluation is also used to detect bowel obstruction, recognize sonographic criteria, and detect the level of obstruction 6.
- Laboratory evaluation, including complete blood count, metabolic panel, and serum lactate level, is essential in the diagnosis and management of intestinal obstruction 4.
Management and Complications
- Management of uncomplicated obstructions includes intravenous fluid resuscitation, nasogastric decompression, and bowel rest, while patients with fever and leukocytosis should receive antibiotic coverage 4.
- Evidence of vascular compromise or perforation, or failure to resolve with adequate nonoperative management, is an indication for surgical intervention 5, 4.