Equine Health Update EHU Vol 19 Issue 3 - Page 34

EQUINE | Proceedings Large Intestine Diseases of the large intestine are commonly responsible for horses undergoing colic surgery. Approximately one third to over half of surgical colic cases are due to dis- ease of the large intestine. In a study modelling survival of horses following surgery for large intestinal disease the 3 most prevalent diagnoses were non-strangulating torsion of the large colon, strangulating torsion (>360° of rotation) and nephrosplenic entrapment, which com- prised 23, 20 and 17% of all cases, respectively (Proud- man et al. 2005). Non operative risk factors found to be associated with reduced survival in this study included signs of cardiovascular compromise (increased pre-op- erative heart rate, increased pre-operative PCV), and in- creasing age. Intra-operative risk factors included resec- tion of the large colon and repeat laparotomy. Large Colon Torsion (greater than or equal to 360 de- grees) Large colon volvulus (LCV) is one of the most painful and rapidly fatal causes of colic in the horse and represents between 10 and 20% of horses with colic that undergo exploratory laparotomy (Tinker et al. 1997). Volvulus greater than or equal to 360 degrees has been found to be strongly associated with poor survival (Kaneene et al. 1997). In a study providing data on the long-term survival of horses with strangulating LCV and identifying pre, intra and post-operative variables associated with survival, it was reported that 76.7% of horses recovered from an- aesthesia (Suthers 2013). Of those horses that survived anaesthesia, 70.8% survived to discharge, 48.3% sur- vived to one year and 33.7% survived to two years. Factors associated with reduced long-term survival were signs of cardiovascular compromise (increasing pre-op- erative PCV), bnormal serosal colour of the large colon intra-operatively, increasing heart rate at 48 hours post- 34 operatively and signs of colic during the post-operat