An 90-year-old man with Alzheimer's has abdominal distention and pain for 12 hours. X-rays show markedly distended colon with a bent inner tube sign. He is hemodynamically unstable with signs of peritonitis. What is the likely diagnosis and the next step after IV fluids and antibiotics?

An 90-year-old man with Alzheimer's has abdominal distention and pain for 12 hours. X-rays show markedly distended colon with a bent inner tube sign. He is hemodynamically unstable with signs of peritonitis. What is the likely diagnosis and the next step after IV fluids and antibiotics?

• A. Sigmoid volvulus; perform exploratory laparotomy
• B. Colonoscopic detorsion; stabilize and observe
• C. Cecal volvulus; perform percutaneous decompression
• D. Intestinal obstruction from adhesions; emergency laparotomy

Answer: (A)

Sigmoid volvulus is the condition at play here. In elderly patients, especially those with neurodegenerative disease and restricted mobility, the sigmoid colon can become markedly redundant and prone to twisting around its mesentery. On plain abdominal radiographs, a massively dilated loop of colon that twists on itself creates the characteristic “bent inner tube” appearance, which points to the sigmoid as the culprit rather than a loop in the small bowel or another colonic segment. When the patient is hemodynamically unstable and shows signs of peritonitis, nonoperative detorsion is unsafe because there may already be bowel ischemia or perforation. These findings mandate urgent surgical exploration rather than endoscopic decompression. The next step after resuscitation with IV fluids and antibiotics is an exploratory laparotomy to untwist the volvulus, evaluate bowel viability, and resect nonviable tissue. Depending on intraoperative findings, the surgeon may perform a sigmoid colectomy with primary anastomosis if the bowel and patient are suitable, or a staged procedure with diversion if contamination or instability is present.

Sigmoid volvulus is the condition at play here. In elderly patients, especially those with neurodegenerative disease and restricted mobility, the sigmoid colon can become markedly redundant and prone to twisting around its mesentery. On plain abdominal radiographs, a massively dilated loop of colon that twists on itself creates the characteristic “bent inner tube” appearance, which points to the sigmoid as the culprit rather than a loop in the small bowel or another colonic segment.

When the patient is hemodynamically unstable and shows signs of peritonitis, nonoperative detorsion is unsafe because there may already be bowel ischemia or perforation. These findings mandate urgent surgical exploration rather than endoscopic decompression. The next step after resuscitation with IV fluids and antibiotics is an exploratory laparotomy to untwist the volvulus, evaluate bowel viability, and resect nonviable tissue. Depending on intraoperative findings, the surgeon may perform a sigmoid colectomy with primary anastomosis if the bowel and patient are suitable, or a staged procedure with diversion if contamination or instability is present.