What are the symptoms and treatment options for bowel obstruction?

Bowel Obstruction: Symptoms and Treatment

The primary symptoms of bowel obstruction include abdominal pain, vomiting, constipation, and abdominal distension, with treatment varying based on whether the obstruction is complete or partial, with surgical intervention required for complete obstruction or signs of strangulation. 1, 2

Symptoms of Bowel Obstruction

Common Symptoms

• Abdominal pain (often colicky and worse after eating)
• Vomiting (more frequent with higher obstructions)
• Constipation or inability to pass gas (absolute constipation in complete obstruction)
• Abdominal distension (a highly reliable physical finding) 1, 2

Warning Signs of Complications

• Fever
• Hypotension
• Diffuse abdominal pain
• Peritonitis (localized tenderness, guarding)
• Tachycardia 2, 3

Diagnostic Approach

Initial Assessment

• History: Previous abdominal surgery (85% sensitivity for adhesive small bowel obstruction), history of cancer, hernias, or inflammatory bowel disease 1
• Physical examination: Abdominal distension, abnormal bowel sounds, localized tenderness 1, 2

Imaging

• CT scan with oral and IV contrast: Gold standard for determining location, cause, and potential complications 2
• Abdominal radiography: Initial screening but cannot exclude the diagnosis 3
• Ultrasound: Alternative diagnostic method, especially useful in pregnant patients 2, 3

Treatment Algorithm

1. Complete vs. Partial Obstruction Assessment

• Complete obstruction: No passage of gas or stool, distended abdomen, vomiting
• Partial obstruction: Some passage of gas or stool, less severe symptoms 1, 2

2. Emergency Surgical Evaluation

Immediate surgical consultation for:

• Signs of strangulation (fever, tachycardia, peritonitis)
• Complete intestinal obstruction with severe pain
• Clinical deterioration 1, 2

3. Management Based on Obstruction Type

A. Complete Obstruction or Signs of Strangulation

• Surgical intervention is the primary treatment 2
• Preoperative preparation:
  • IV fluid resuscitation
  • Correction of electrolyte imbalances
  • Nasogastric tube decompression
  • Broad-spectrum antibiotics if infection suspected 2, 3

B. Partial Obstruction without Strangulation

• Conservative management:

  • Nasogastric tube decompression (for significant distension and vomiting)
  • IV fluid resuscitation
  • Nothing by mouth initially
  • Serial clinical assessments
  • Water-soluble contrast agent via NG tube (successful in 83-100% of cases) 2
  • Consider octreotide for high-output obstruction 1

• Failed conservative management (symptoms persist after 24-48 hours):

  • Surgical intervention 2

4. Special Considerations

Malignant Bowel Obstruction

• Surgical approach for patients with good performance status and limited disease
• Medical management for poor surgical candidates (advanced disease, carcinomatosis, poor performance status):
  • Opioids for pain control
  • Antiemetics for nausea/vomiting
  • Octreotide to reduce gastrointestinal secretions
  • Corticosteroids to reduce inflammation
  • Consider self-expanding metallic stents for gastric outlet, proximal small bowel, or colonic obstruction 1, 4

Post-Treatment Care

• Early mobilization
• Progressive diet advancement when appropriate
• Monitoring for signs of recurrent obstruction
• Close follow-up to identify underlying causes 2

Common Pitfalls and Caveats

1. Delayed recognition of strangulation can lead to bowel necrosis and increased mortality
2. Overreliance on plain radiographs which cannot exclude obstruction
3. Using prokinetic agents (like metoclopramide) in complete obstruction, which can worsen symptoms
4. Failure to recognize rare causes of obstruction such as large uterine fibroids, which require specific management 5, 6
5. Mistaking pseudo-obstruction for mechanical obstruction, which requires different management approaches 7

Early recognition of symptoms and prompt appropriate intervention are crucial to reduce morbidity and mortality in bowel obstruction.