Surgical techniques in equine colic.

This research paper discusses the various surgical procedures that can be employed in the event of equine intestinal obstructions, as well as the tools, preparations and techniques necessary to seek out and resolve the source of the problem. The focus is on maximizing the efficiency and success of abdominal surgery, ideally performed by a team of surgeons.

Understanding the Need for Surgery

• Equine abdominal surgery is typically an emergency procedure due to complications with the horse’s abdominal area; usually linked to intestinal obstructions.
• To efficiently manage the surgery, a team of surgeons is recommended.
• The surgical site is subjected to maximum protection using sterile drapes and wound protectors to prevent infections.

Selection of Surgical Approach

• For most intestinal obstructions, a ventral midline laparotomy incision is preferred as it provides the easiest access.
• Alternatively, a standing laparotomy through the left paralumbar fossa can be used for adequate exploration of the abdomen, primarily used as a diagnostic tool.
• The overall tolerance of horses towards these incisions is high, making these procedures viable.

Investigating the Intestinal Obstruction

• If the cause of the obstruction is not immediately evident, a systematic exploration of the abdominal cavity is necessary.
• If the obstruction still remains undetected, a bowel exteriorization is required for deeper examination.
• The decision-making process on bowel resection is largely subjective, and dependent on the assessment of bowel functionality. In cases of equivocal assessments, surgeons are advised to resect some normal bowel rather than risk leaving compromised bowel tissue in place.

Common Causes of Obstruction and their Resolutions

• Small intestinal obstructions are often linked to incarcerations which occur when the small intestine is trapped in the epiploic foramen, the inguinal canal, or an umbilical hernia.
• In cases of thromboembolic compromise to intestinal vessels, the largest portions of affected bowel require resection.
• Impactions, particularly in the caecum, are commonly linked with obstructive issues. Large colon torsions of 270 degrees or less can be fixed via surgical manipulation. However, 360 degrees torsions usually result in vascular compromise sufficient to devitalize the organ.
• In such cases, enterotomy (surgical incision into the intestine) of the large colon can help retrieve obstructions like enteroliths (intestinal stones).

Closing the Surgery

• A two-layer end-to-end anastomosis (surgical connection of tissue) is commonly used to conclude the surgery.
• Modern automated stapling and ligating instruments have proven beneficial in reducing surgical time.
• Antibiotics are placed into the peritoneal cavity before the abdomen is closed for preventing infections.
• Drains are placed into the abdominal cavity, for peritoneal cavity drainage after the surgery.
• Suturing the peritoneum and the linea alba (fibrous structure running down the midline of the abdomen), contributes to the closure of the abdomen.

Resulting Improvements

• Applying such principles and techniques has significantly increased the success rates of abdominal surgeries in equine patients.