A 72-year-old man with a long history of chronic constipation presents with acute onset of abdominal pain, distension, and inability to pass stool or flatus for 2 days. On examination, he is afebrile, BP 130/80, with a markedly distended abdomen. Abdominal X-ray shows a hugely dilated sigmoid colon with a characteristic "coffee-bean" or "omega" configuration. The transition point is at the rectosigmoid junction. What is the most appropriate next step in management?

Explanation

## Management of Acute Sigmoid Volvulus ### Diagnosis Confirmed **Key Point:** The **coffee-bean sign** (or omega loop) with a transition point at the rectosigmoid junction is pathognomonic for sigmoid volvulus. This is a mechanical obstruction of the large bowel, not small bowel, and requires urgent decompression. ### Clinical Context: Why This Patient? - **Age 72** — sigmoid volvulus is a disease of the elderly. - **Chronic constipation** — predisposes to volvulus by allowing the sigmoid to become elongated and redundant. - **Acute presentation** — sudden onset of obstruction indicates the twist has occurred acutely. - **Afebrile, hemodynamically stable** — no signs of perforation or strangulation (yet). ### Management Algorithm for Sigmoid Volvulus ```mermaid flowchart TD A[Acute sigmoid volvulus<br/>confirmed on imaging]:::outcome --> B{Signs of perforation<br/>or peritonitis?}:::decision B -->|Yes| C[Immediate laparotomy<br/>Hartmann's procedure]:::urgent B -->|No| D[Attempt non-operative<br/>decompression]:::action D --> E[Rectal tube or rigid<br/>sigmoidoscopy + decompression]:::action E --> F{Successful<br/>decompression?}:::decision F -->|Yes| G[Elective sigmoid colectomy<br/>in 4-6 weeks]:::action F -->|No| H[Emergency laparotomy<br/>+ resection]:::urgent C --> I[Definitive surgery<br/>after stabilization]:::action G --> J[Prevent recurrence]:::outcome ``` ### Why Decompression First? **High-Yield:** In an **uncomplicated** (no perforation, no peritonitis) acute sigmoid volvulus, the first step is **non-operative decompression** via rectal tube or rigid sigmoidoscopy. Success rates are 60–90% for initial decompression. | Step | Method | Success Rate | Next Action | |------|--------|--------------|-------------| | **1st line** | Rectal tube (Foley/flatus tube) | 40–50% | Observe; if fails, proceed to sigmoidoscopy | | **2nd line** | Rigid sigmoidoscopy + air insufflation | 80–90% | Elective colectomy in 4–6 weeks | | **3rd line** | Flexible sigmoidoscopy (if rigid unavailable) | 70–80% | Elective colectomy | | **Failed decompression** | Emergency laparotomy | — | Hartmann's or primary resection | ### Why NOT Immediate Surgery? **Clinical Pearl:** Immediate laparotomy in an uncomplicated case is **overtreatment**. The patient is hemodynamically stable, afebrile, and has no signs of perforation. Decompression allows time for: - Bowel wall edema to resolve. - Ischemia risk to decrease. - Elective (not emergency) surgery, with better outcomes and lower morbidity. **Key Point:** Emergency surgery carries higher mortality (10–30%) than elective surgery (5–10%) for sigmoid volvulus. ### Why NOT Conservative Management Alone? **Warning:** Nasogastric tube and fluids alone do NOT address the mechanical obstruction. The sigmoid will re-twist in 50% of cases if decompression is not attempted. Recurrence rates after failed decompression are high; elective colectomy is definitive. ### Why NOT Barium Enema? **Warning:** Barium enema is contraindicated in acute obstruction and suspected perforation (risk of peritonitis). The diagnosis is already confirmed on plain X-ray. Barium would delay urgent decompression. ### Definitive Management: Elective Sigmoid Colectomy After successful decompression, the patient should undergo **elective sigmoid colectomy** in 4–6 weeks to prevent recurrence. Recurrence rates without surgery are 50–90%. **Mnemonic: DECO** — **D**ecompress, **E**lective, **C**olectomy, **O**utcome (prevent recurrence).