A 58-year-old man with a history of three previous abdominal surgeries presents with acute onset colicky abdominal pain, abdominal distension, and vomiting for 8 hours. On examination, he is haemodynamically stable, abdomen is distended with visible peristaltic waves, and bowel sounds are high-pitched and tinkling. Plain abdominal X-ray shows dilated small bowel loops with air-fluid levels and a transition zone. What is the most appropriate next step in management?

Explanation

## Clinical Scenario Analysis This patient presents with **acute small bowel obstruction (SBO)** with classic features: - Colicky pain, vomiting, distension - High-pitched tinkling bowel sounds - Plain X-ray showing dilated small bowel, air-fluid levels, and a transition zone - Haemodynamically stable - History of previous abdominal surgery (adhesions likely cause) ## Management Algorithm for Acute SBO ```mermaid flowchart TD A[Acute SBO suspected]:::outcome --> B{Haemodynamically stable?}:::decision B -->|Yes| C[NGT decompression + IV fluids + electrolytes]:::action B -->|No| D[Resuscitate + ICU]:::urgent C --> E{Resolves in 24-48 hrs?}:::decision E -->|Yes| F[Continue conservative management]:::action E -->|No| G[CT abdomen to assess viability + site]:::action G --> H{Strangulation / ischemia?}:::decision H -->|Yes| I[Emergency laparotomy]:::urgent H -->|No| J{Complete vs partial?}:::decision J -->|Complete + failed conservative| K[Surgical exploration]:::action J -->|Partial / improving| L[Continue medical management]:::action ``` ## Key Point: **Conservative (non-operative) management is the first-line approach for acute SBO in haemodynamically stable patients**, particularly when adhesions are the likely cause (80–90% of cases resolve with conservative therapy). ### Components of Conservative Management: 1. **Nasogastric tube (NGT)** — decompresses proximal bowel, reduces vomiting, decreases risk of aspiration 2. **Intravenous fluids** — correct hypovolaemia and electrolyte abnormalities (hypokalaemia, hyponatraemia, hypochloraemia) 3. **Electrolyte correction** — essential for bowel motility recovery 4. **Observation period** — 24–48 hours allows time for adhesions to lyse or obstruction to resolve spontaneously ## High-Yield: **Indications for early surgical intervention (< 24 hrs):** - Haemodynamic instability - Peritoneal signs (guarding, rigidity) - Fever + tachycardia (suggests strangulation) - Imaging evidence of closed-loop obstruction or volvulus - Complete obstruction with no improvement after 24–48 hours of conservative management ## Clinical Pearl: In this case, the patient is **haemodynamically stable with no signs of strangulation** (no fever, no peritoneal signs). Therefore, conservative management is appropriate first. If symptoms persist beyond 48 hours or signs of strangulation develop, then CT abdomen and surgical exploration are warranted. ## Warning: ~~Immediate laparotomy~~ is NOT indicated in stable patients with uncomplicated adhesive SBO — it increases morbidity and mortality compared to selective operative management. Adhesiolysis itself can cause new adhesions. [cite:Sabiston Textbook of Surgery Ch 45]