What is the diagnosis and management for a 28-year-old female with recurrent episodes of vomiting green color, occurring annually for 5-6 years, relieved by insertion of a Ryle's (nasogastric) tube and passage of stool?

Recurrent Small Bowel Obstruction with Cyclic Pattern

This patient most likely has recurrent partial small bowel obstruction from adhesive bands, and requires urgent CT imaging during a symptomatic episode to identify a transition point, followed by surgical consultation if mechanical obstruction is confirmed. 1

Differential Diagnoses

Most Likely: Adhesive Band Obstruction

• Green bilious vomiting indicates proximal small bowel obstruction, with the color resulting from bile reflux into the stomach 1, 2
• The cyclic nature (annual episodes over 5-6 years) and relief with nasogastric decompression followed by stool passage strongly suggests intermittent mechanical obstruction from adhesive bands 1
• Adhesive band obstruction accounts for approximately 15% of late adhesive obstructions and can occur even without prior abdominal surgery (from inflammatory conditions like appendicitis or adnexitis) 3
• The key diagnostic feature is a distinct transition point between dilated and normal bowel on imaging, though this may not be visible if the obstruction has resolved or if bowel is fixed by adhesions 1

Alternative Considerations

• Internal hernia (especially if prior bariatric surgery): requires urgent laparoscopic exploration within 12-24 hours due to high strangulation risk 1, 4
• Intussusception: rare (0.1-0.3% incidence) but can cause intermittent obstruction with similar presentation 1
• Chronic small intestinal dysmotility: less likely given the acute episodic nature and complete resolution between episodes, but should be considered if no mechanical cause is found 1

Less Likely but Important to Exclude

• Malignant obstruction: unlikely given young age and long duration without progression, but requires exclusion 1
• Radiation stricture or anastomotic stenosis: only if relevant surgical history 1

Diagnostic Workup

During Acute Episode

• Obtain CT abdomen with IV contrast immediately during symptomatic episode to capture the transition point that may not be visible when obstruction resolves 1
• Abdominal ultrasound can be highly sensitive for detecting dilated bowel loops and transition points 3
• Plain radiographs show dilated small bowel with air-fluid levels but are less specific 2

Between Episodes

• Contrast follow-through studies or MRI enterography may miss intermittent obstruction but can identify anatomic abnormalities 1
• If imaging is repeatedly negative despite classic symptoms, consider small bowel manometry to evaluate for dysmotility disorders 1
• Check inflammatory markers (CRP, albumin, fecal calprotectin) to exclude inflammatory bowel disease 1

Critical Diagnostic Clue

• A supportive diagnostic test: if symptoms improve or resolve on a low-residue or liquid diet, this strongly suggests mechanical obstruction rather than dysmotility 1

Management Strategy

Acute Episode Management

• NPO status with nasogastric tube decompression using low intermittent suction (40-60 mmHg) to prevent aspiration and reduce intraluminal pressure 2
• IV fluid resuscitation and electrolyte correction 2, 4
• Monitor for signs requiring urgent surgery: peritonitis, fever, hypotension, diffuse pain, elevated lactate (indicating strangulation/ischemia with 25% mortality) 2
• Conservative management resolves 70-90% of adhesive small bowel obstructions 2, 4

Nasogastric Tube Removal Criteria

• Remove NG tube when output is <10cc over 14 hours AND patient passes stool, indicating restored intestinal transit 5
• Advance diet from clear liquids as tolerated after NG removal 5

Surgical Intervention Indications

• Failure of conservative management after 48-72 hours 2
• Signs of strangulation or ischemia (fever, peritonitis, elevated lactate) 2
• Recurrent episodes despite conservative management warrant elective surgical exploration to divide adhesive bands and prevent future episodes 1, 3

Long-term Management Between Episodes

• Low-residue diet to minimize risk of recurrent obstruction 1
• Avoid medications that slow intestinal motility (opioids, anticholinergics) 2, 4
• Schedule follow-up within 1-2 weeks after each episode to assess complete resolution 5, 4
• Educate patient on warning signs requiring urgent evaluation: severe persistent pain, continuous vomiting, inability to pass flatus/stool >24 hours, abdominal distension with absent bowel sounds 4

Critical Pitfalls to Avoid

• Do not delay CT imaging during symptomatic episodes - the transition point may only be visible when obstruction is active 1
• Do not give antimuscarinics (dicyclomine) or high-dose opioids - these worsen obstruction 2
• Do not assume functional disorder without excluding mechanical causes - premature labeling makes subsequent management difficult 1
• Radiographic confirmation of NG tube position is mandatory before use - bedside auscultation alone is unreliable 2
• In post-bariatric surgery patients, maintain very low threshold for surgical exploration due to high risk of internal hernia 1, 4