Diagnosis, management and prognosis of small colon impactions

Abstract

Common causes of obstruction of the small colon and rectum include diffuse faecal impaction, enterolithiasis, faecalithiasis, phytobezoar, trichobezoar, phytotrichobezoar, phytoconglobate, foreign body, intramural haematoma and retained meconium. Poor dentition, poor-quality hay, lack of adequate water, parasite damage and lack of exercise are risk factors for the development of small colon impactions. Clinical signs of small colon obstruction develop slowly because a large space proximal to the obstruction allows ingesta, gas and fluid to accumulate. Medical management of horses with faecal impaction of the small colon involves improvement of hydration, stimulation of colonic motility, softening the impaction by the administration of osmotic laxatives or lubricants, and control of pain. Surgical intervention is indicated when medical management fails to resolve the impaction or when intractable pain and a deteriorating cardiovascular status ensues.

Small Colon Faecalith with Large Colon Displacement in Ten Cases (2015–2023): A Detailed Case Description and Literature Review

“…As such, any condition leading to gas accumulation may pose a risk factor for the development of LCD or LCV. While LCD or LCV might be the primary reason for equine referral, these are likely to be secondary conditions stemming from an underlying problem, such as small colon impaction, which may require a more investigative diagnosis [11]. Small colon impaction is typically linked to mild colic pain, which can exacerbate due to oral distension of the intestine caused by the obstruction [12,13].…”

“…Abdominal distension may be severe in horses with complete obstruction of the small colon lumen, leading to an increase in heart rate and abdominal pain in those horses requiring surgery [13]. Faecal impaction is the prevalent condition affecting the small colon in horses (34% of small colon disease) [11,13]. However, this intestinal tract can be occasionally focally obstructed by a faecalith, enterolith, phytobezoar, and trichobezoar [14,15].…”

“…Faecaliths are made up of concretions of dry and inspissated faecal material, characterised by a more distinct shape than general feed impaction [15]. Small colon faecaliths (SCF) represent one of the most common obstructions among focal impactions [11,[14][15][16]. According to Dart and colleagues (1992), American Miniature Horses, Arabians, ponies, and horses aged over 15 years are predisposed to this condition [17], although other studies have not identified breed or age as predisposing factors [18][19][20][21][22][23].…”

“…Several risk factors for an SCF, including the ingestion of poorquality hay, inadequate dentition, insufficient mastication, intestinal motility disorders, parasite damage, and reduced water intake, have been reported [12,22]. Initial clinical signs of SCF are often nonspecific and vague, with symptoms like mild abdominal pain, lethargy, decreased faecal passage, or diarrhoea [11,23,24]. Additionally, transabdominal ultrasonography (US) and RP findings are typically not helpful in diagnosing a specific site of small colon obstruction such as SCF, attributable to the lack of specificity [11].…”

“…Initial clinical signs of SCF are often nonspecific and vague, with symptoms like mild abdominal pain, lethargy, decreased faecal passage, or diarrhoea [11,23,24]. Additionally, transabdominal ultrasonography (US) and RP findings are typically not helpful in diagnosing a specific site of small colon obstruction such as SCF, attributable to the lack of specificity [11]. Due to the complexity of making a definitive diagnosis of SCF, it may sometimes be unappreciated, resulting in intestinal distension and ultimately in the exacerbation of colic symptoms.…”