What is the gold standard for diagnosing Small Bowel Obstruction (SBO)?

From the Guidelines

The gold standard for diagnosing small bowel obstruction (SBO) is computed tomography (CT) scan. This imaging modality provides crucial information related to the underlying cause of SBO and predicts the need for emergency surgery, making it the primary diagnostic tool of choice in patients with SBO 1. The introduction of multidetector-row computed tomography (MDCT) has improved the diagnostic accuracy with high sensitivity and specificity for the etiology of SBO (87 and 90%, respectively) 1.

Key Benefits of CT Scan

• Provides information about the underlying cause of obstruction and predicts the need for emergency surgery
• Helps define the potential location of the obstruction, the grade of the obstruction, and may identify a possible transition zone
• Can identify a possible alternative diagnosis if no signs of bowel obstruction are present
• Findings on CT scan can predict the need for operative management, including closed-loop obstruction, markers of bowel ischemia, and the “small bowel feces sign”

Diagnostic Approach

• CT scan plays a key role in the decision on the management of patients with SBO
• The use of water-soluble contrast optimizes the diagnostic value of CT scan
• X-ray can evaluate the progress of the contrast at 24 h after CT
• Adhesions are a major cause of SBO, and the absence of other etiologies and a transition zone are highly predictive for adhesions as the cause of the obstruction 1

Clinical Implications

• When adhesive etiology is established by CT, patients with SBO can be treated according to the same management algorithms as other patients with adhesive small bowel obstruction
• CT scan is essential for comprehensive evaluation and should be specified as "CT abdomen/pelvis with IV contrast" to optimize diagnostic accuracy 1

From the Research

Diagnosis and Management of Small Bowel Obstruction (SBO)

The gold standard for diagnosing and managing SBO involves a combination of clinical evaluation, imaging studies, and surgical intervention when necessary.

• Clinical evaluation includes history and physical examination to identify signs of strangulation, such as fever, hypotension, diffuse abdominal pain, and peritonitis 2.
• Imaging studies, such as computed tomography (CT) scans and ultrasound, are reliable diagnostic methods for SBO 2, 3.
• Management includes intravenous fluid resuscitation, analgesia, and determining the need for operative vs. nonoperative therapy 2, 4.

Role of Imaging Studies

Imaging studies play a crucial role in the diagnosis and management of SBO.

• CT scans with multiplanar reconstructions can provide incremental clinically relevant information over plain films and may lead to changes in management 3.
• Water-soluble contrast studies can be considered in patients who do not clinically resolve after 48 to 72 hours for both diagnostic and potential therapeutic purposes 3.

Surgical Intervention

Surgical intervention is necessary for patients with strangulation, those who fail nonoperative therapy, and those with evidence of bowel compromise 2, 4, 3.

• Laparoscopic techniques are gaining acceptance as a primary modality in the treatment of SBO and can reduce postoperative pain, minimize hospital stay, and may lead to fewer adhesions 4.
• Appropriate patient selection is necessary for successful laparoscopic SBO management 4.

Nonoperative Management

Nonoperative management is suitable for patients without signs of strangulation or bowel compromise.

• Nasogastric tube decompression and bowel rest can be effective in managing SBO 2, 5.
• Parenteral nutrition can be considered as an alternative to early reoperation in patients with persistent early postoperative SBO 6.