Diagnosis, management and prognosis of large colon impactions

Abstract

The majority of large colon feed impactions occur in the left ventral colon at the pelvic flexure. Sand and enterolith impactions most commonly occur in the left ventral colon at the pelvic flexure or in the right dorsal colon; however, sand can accumulate anywhere along the gastrointestinal tract. Enteral fluid therapy can, in most cases, supplement or even replace i.v. administration of fluids and it appears effective and safe to soften large colon contents and resolve simple large colon impactions. Surgical intervention is indicated when a concurrent displacement is suspected, as lengthy medical treatment of large colon impaction secondary to large colon displacements would not be indicated and may increase the risk of colonic rupture. Other indications for surgical intervention include uncontrollable pain, when cardiovascular parameters deteriorate, or when there is evidence of intestinal devitalisation. The prognosis for horses undergoing large colon enterotomy is dependent on the extent and type of impaction, but is generally excellent. Diagnosis Feed impaction Horses with a large colon feed impaction (Fig 2) typically have signs of mild to moderate abdominal pain, decreased

Use of a pneumatic device for intraluminal enterolith fragmentation in horses

“…In these cases, teniotomy or enema with lubricants and water may be used to facilitate enterolith mobilisation to bowel segments that can be more easily accessed. Mobilisation manoeuvres may cause intestinal perforation (Hanson & Schumacher, 2021; Hassel & Yarbrough, 1998; Klohnen, 2013; Schumacher & Mair, 2002) and increase the risk of adhesion formation (Hopster‐Iversen et al, 2011; Smith et al, 2005; Van Hoogmoed & Snyder, 1997). In this study, mobilisation manoeuvres were limited to cases of partial obstruction in which enteroliths were not stuck to the intestinal wall.…”

Strategies to relieve intraluminal obstructions in inaccessible segments of the ascending, transverse and descending colon

“…While the inclusion of mucosa within descending colon enterotomies has not been determined to be essential (Beard et al, 1989), it does appear to be advantageous to compress submucosal vessels for the large colon (Doyle et al, 2003). Since intramural or submucosal haematomas can occur spontaneously in the descending colon (Hanson & Schumacher, 2021; Schumacher & Mair, 2002), full‐thickness closure of descending colon enterotomies appears prudent as well. While lumen diameter is not limiting for closure of right dorsal colon enterotomies, it is important to be precise with conservative suture bite sizes and minimal inversion when closing descending colon enterotomies.…”

“…This entails using intraluminal lavage through a pelvic flexure enterotomy to evacuate all ingesta oral to the obstruction (right dorsal colon, including ampulla coli, and oral transverse colon, as applicable). Once the colon is emptied of ingesta, water distension of the colon combined with gentle ballottement of the obstruction can free it from the mucosa and allow it to move orally into the ampulla coli where it then can be manipulated within the dorsal colon and exteriorised from the abdomen (Hanson & Schumacher, 2021; Hassel, 2002; Oreff et al, 2020; Pierce, 2009). This author has observed on some occasions that the transverse colon appears to spasm orally to obstructions in the transverse colon, and this spasming does not consistently relax with fluid distension.…”

“…For obstructions that are not resolved by hydropulsion, particularly obstructions in the mid to distal transverse colon and very oral descending colon or the very aboral descending colon, retropulsion or retrograde flushing may be a useful technique (Hanson & Schumacher, 2021; Klohnen, 2013; Oreff et al, 2020; Pierce, 2009; Pierce et al, 2010; Schumacher & Mair, 2002; Taylor et al, 1979). Retropulsion was used in 13% of descending colon enterolith obstructions in one case series (Pierce et al, 2010).…”

“…Enteroliths, faecaliths, ingested foreign bodies and bezoars are examples of focal intraluminal obstructions that can lodge in inaccessible parts of the gastrointestinal tract (Hanson & Schumacher, 2021; Hassel, 2002; Klohnen, 2013; Oreff et al, 2020; Pierce et al, 2010). Gastrointestinal segments that are particularly difficult to surgically access and manage include stomach, duodenum, distal ileum, base and dorsal body of caecum, aboral right dorsal colon, transverse colon and the most oral and aboral limits of the descending (small) colon (Marshall & Blikslager, 2019).…”