Abdominal adhesions–have we made any progress?

The research discusses the problem of abdominal adhesions in equine patients undergoing colic surgery. The survival rates following such surgery have increased over the past years but a significant proportion of horses continue to suffer from abdominal discomfort due to the formation of abdominal adhesions.

Survival Rates Following Colic Surgery

• The research notes a marked improvement in survival rates for equines undergoing abdominal surgery over the last two decades.
• About 65% of surgical colic patients are discharged alive from veterinary hospitals. However, long term survival rate is around 55%, reflecting a decrease due to post-operative fatalities.

Post-operative Abdominal Adhesions

• Abdominal adhesions are considered to be the primary cause of post-operative mortality and morbidity in horses. This is particularly evident in those who have undergone small intestinal surgery.
• Despite these findings, accurately identifying the incident rate of abdominal adhesion formation following colic surgery remains challenging as not all cases are lethal, and only a fraction of the original study population gets reported.

Comparative Incidence in Humans and Horses

• Studies have shown that 95% of human patients undergoing secondary laparotomy displayed evidence of adhesion formation, with a minority remaining asymptomatic.
• In contrast, equine patients showed a 33% incidence of adhesions, twice the rate of symptomatic adhesions at 16%.
• Interestingly, symptomatic adhesions appear to be more common in equines compared to other species, potentially due to specific anatomical and physiological characteristics of the horse.

Adhesion Risk in Foals Versus Mature Horses

• It is generally accepted that foals have a higher risk of developing adhesions compared to adult horses. Yet, the actual incidence rates found in this and other studies do not support this perception.
• The incidence of symptomatic adhesions was actually similar in foals and adults. However, these studies did not solely focus on individuals with small intestinal lesions where the risk of adhesions is believed to be higher.

Further Research Required

• Despite advances in other areas related to this surgery like anaesthetic management, the issue of adhesion formation remains an unresolved problem in equine abdominal surgery.
• There is an urgent need to further investigate the pathophysiology of adhesion formation to ultimately increase the success rate and long-term wellness of equines undergoing colic surgery.