Mnemonic

Paracolic Gutters

A memory aid for the paracolic gutters and where fluid tracks within them.

Expansion

Grooves lateral to the ascending and descending colon; the right is deeper and continuous with the subhepatic space

Expansion

  • Right paracolic gutter - lateral to the ascending colon. Deeper, and continuous upwards with the right subhepatic space (Morison’s pouch) and the right subphrenic space
  • Left paracolic gutter - lateral to the descending colon. Its upward extension is limited by the phrenicocolic ligament

The asymmetry has real consequences. Pus from a perforated appendix or a perforated duodenal ulcer flows up the right gutter to collect beneath the diaphragm, producing a subphrenic abscess with shoulder tip pain and a sympathetic pleural effusion.

Conversely, fluid tracking downwards from either gutter collects in the pelvis, in the rectovesical or rectouterine pouch, the most dependent part of the peritoneal cavity in the supine patient and therefore the commonest site of a pelvic collection.