sigmoid volvulus

see also:

• central / periumbilical abdominal pain in the ED
• caecal volvulus
• Emedicine

• volvulus occurs when colon twists on its mesenteric axis with a greater than 180-degree rotation, producing obstruction of intestinal lumen and mesenteric vessels
• the most common location is at the sigmoid (see also caecal volvulus, and also may less commonly occur at splenic flexure or transverse colon))
• in Western countries, the far majority occur in elderly mainly bed bound patients

• in Western countries, the far majority occur in bed bound elderly patients with chronic constipation
• rarely, may occur in young adults with:
  • adult Hirschsprung's disease
  • those from developing countries with high fibre diets being thought to be a major cause

• total bowel obstruction
• sudden onset periumbilical pain with vomiting and constipation
• upper abdominal distention with tympany
• empty rectum
• visible peristalsis may be seen
• may have peritoneal signs
• gangrene and perforation occur early

• partial bowel obstruction
• especially elderly
• more subtle clinical picture often leading to delayed diagnosis
• poorly characterised abdominal cramping esp. on left side
• upper abdominal distention with tympany
• empty rectum
• visible peristalsis may be seen

• omega or horseshoe sign
• bird's beak sign
• Y sign
• northern exposure sign
• coffee bean sign
• bent inner tube or ace of spades sign
• left pelvic overlap or left flank overlap sign
• liver overlap sign
• the whirl sign
• empty left iliac fossa sign

Coffee bean sign courtesy of ncbi

• discuss with surg. registrar ASAP
• if evidence of bowel ischaemia (eg. fever, tachycardia, peritonism, or air in bowel wall on plain CT abdo), then needs iv antibiotics and urgent surgery
• if no evidence bowel ischaemia, usually needs urgent rectal tube to decompress and this will usually resolve the volvulus