caecal volvulus

see also:

• central / periumbilical abdominal pain in the ED
• sigmoid volvulus
• Emedicine - cecal volvulus

• whilst in most people, the caecum is retroperitoneal and not susceptible to volvulus, in 20% there is a congenital incomplete peritoneal covering which allows a mobile caecum on a mesentery such that it now longer lies in the RIF.
• it is in this group with the anatomic variant in whom caecal volvulus may occur, particularly if there is ALSO a restriction of the bowel at a fixed point due to adhesions or abdominal masses.
• risk factors thus include:
  • prior abdominal surgery
  • presence of a pelvic mass
  • violent coughing
  • atonia of the colon
  • extreme exertion
  • unpressurized air travel
  • third-trimester pregnancy
• volvulus may cause small bowel obstruction, bowel ischaemia and perforation and peritonitis
• cecal volvulus accounts for ~11% of all intestinal volvulus and tends to occur in younger adults (usually aged 30-60yrs) than doses sigmoid volvulus which tends to occur in the elderly population.

• presents as a proximal large bowel obstruction over hours or days
• usually with colicky abdominal pain, vomiting and abdominal distension
• may have a distended, tympanic abdomen
• fever, hypotension suggest ischaemia +/- perforation

• plain AXR has sensitivity of ~75-80% for detecting cecal volvulus
• can diagnose a large intestine obstruction, but are insufficient to confirm the diagnosis of cecal volvulus in most patients

• ~50% twist in the axial plane:
  • the dilated caecum thus appears in the RLQ
• ~50% twist and invert causing a closed loop
  • the dilated caecum thus appears in the LUQ
• ~10% fold without torsion causing a caecal bascule
  • often seen as a dilated loop in the mid abdomen

• severe caecal distension > 10cm is suggestive but present in less than 50%!
• “Despite the varying positions of the distended cecum, the plain radiographic features of a caecal volvulus are characteristic, and the caput caecum can typically be identified. The colonic haustral pattern is generally maintained in contradistinction to a sigmoid volvulus although some effacement may be present if ischemia develops.
• When shorter segments of the colon and cecum are involved, the distended caecum may be found in the normal location. In most patients, obstruction is almost complete and the distal colon is usually empty and the small bowel frequently distended.”¹⁾

• cecal volvulus is suggested by the extreme dilatation of the cecum
• overall CT scan is said to have ~90% sens for detecting cecal volvulus
• the absence of distal colonic decompression on CT topograms makes the diagnosis very unlikely
• sensitivity of findings:²⁾³⁾
  • on CT topograms:
    • cecal dilatation > 10cm (45% sens 100% spec)
    • coffee bean sign (27% sens, 92% spec) (NB. coffee bean sign with axis LLQ-RUQ indicates sigmoid volvulus)
    • cecal apex in LUQ (45% sens, 100% spec)
    • distal colon decompression (91% sens, 83% spec)
  • on cross-sectional CT images:
    • distal colon decompression (91% sens, 91% spec)
    • cecal dilatation > 10cm (45% sens 100% spec)
    • cecal apex in LUQ (36% sens, 100% spec)
    • whirl sign (73% sens, 100% spec)
    • ileocecal twist (54% sens, 100% spec)
    • transition point(s) (82% sens, 100% spec)
    • X-marks-the-spot (27% sens, 100% spec)
    • split wall (54% sens, 100% spec)
  • CT signs of bowel ischemia correlated poorly with pathology report findings

• nil orally
• iv fluids
• analgesia
• FBE, U&E, +/- lactate
• AXR, erect CXR to help exclude perforation
• surgical consult ASAP as most require laparotomy, and if there is colonic ischaemia, right hemicolectomy.