Initial Management of Bowel Obstruction

Diagnosis and Assessment

Bowel obstruction accounts for approximately 15% of hospital admissions for acute abdominal pain and 20% of cases requiring acute surgical care 2
Initial evaluation should focus on identifying signs of peritonitis, strangulation, or ischemia, which would require emergency surgery 1
Physical examination should include assessment of abdominal distension, abnormal bowel sounds, and examination of all hernial orifices 1
Laboratory tests should include complete blood count, C-reactive protein, lactate, electrolytes, BUN/creatinine, and coagulation profile 1
Elevated C-reactive protein, leukocytosis with left shift, and elevated lactate may indicate peritonitis or intestinal ischemia 1

CT scan with intravenous contrast is the preferred imaging technique with superior diagnostic accuracy compared to conventional radiography and ultrasound 3, 1
CT can identify the location, degree, and potential causes of obstruction 1
Abdominal plain X-ray is often the first radiologic study performed but has limited diagnostic value (50-60% sensitivity) 3
Water-soluble contrast administration enhances diagnostic value and can predict the need for surgery 3, 1
If contrast has not reached the colon on an abdominal X-ray 24 hours after administration, this indicates a high likelihood of non-operative management failure 3

Non-surgical management is effective in approximately 70-90% of patients with intestinal obstruction due to adhesions 1
Key components include NPO, decompression with nasogastric tube or long intestinal tube, fluid resuscitation with crystalloids, monitoring and correction of electrolytes, and water-soluble contrast administration 1
Long intestinal tubes may be more effective than nasogastric tubes but require endoscopic insertion 1

Immediate surgical intervention is required for signs of peritonitis, strangulation, intestinal ischemia, closed-loop obstruction on imaging, or failure of non-surgical management after 72 hours 1

For malignant bowel obstruction, surgery after CT scan is the primary treatment option for patients with longer life expectancy 4, 5
For patients with advanced disease or poor condition, medical management may include pharmacologic measures, parenteral fluids, endoscopic management, enteral tube drainage, and somatostatin analogs 4, 5
For sigmoid volvulus without ischemia, endoscopic detorsion followed by same-admission sigmoid colectomy with primary anastomosis is recommended 6
For obstructing left colon cancer, self-expanding metallic stents may be preferred to colostomy as they are associated with similar mortality/morbidity rates but shorter hospital stay 6, 1

Common complications include dehydration with renal injury, electrolyte disturbances, malnutrition, and aspiration 1
Antiemetics that increase gastrointestinal motility should not be used in patients with complete obstruction but may be beneficial in partial obstruction 4, 5
Recurrence of intestinal obstruction due to adhesions is possible after non-surgical management (12% within 1 year, increasing to 20% after 5 years) 1
Water-soluble contrast agents may further dehydrate patients due to their higher osmolarity, shifting fluids into the bowel lumen 3