Use of perioperative variables to determine the requirement for repeat celiotomy in horses with postoperative reflux after small intestinal surgery.

Objective: To determine whether perioperative variables can be used to differentiate a medical vs a surgical reason for postoperative reflux (POR) after small intestinal (SI) surgery in horses.

Study Design: Retrospective study.

Sample Population: Horses >1 year of age that recovered from SI surgery and had POR.

Methods: Medical records of horses that underwent SI surgery and developed POR from 2009-2015 were reviewed. Surgical reasons for POR were defined as an anastomosis complication, mechanical obstruction, or nonviable intestine identified at repeat celiotomy/necropsy. A medical reason for POR was presumed when the POR improved with medical treatment or when no surgical reasons were identified at repeat celiotomy/necropsy. Perioperative variables were analyzed and used to develop a logistic regression model.

Results: Fifty-one horses had POR after SI surgery. After initial SI surgery, 14 horses had surgical reasons for POR diagnosed at repeat celiotomy or necropsy. Thirty-seven horses were considered to have medical reasons for POR because their POR resolved with medical management or functional ileus was diagnosed at repeat celiotomy/necropsy. A greater volume and a greater duration of POR were not associated with a surgical reason for POR. Rather, a postoperative (PO) fever and the timing of colic in the PO period were associated with a surgical reason for POR.

Conclusion: Horses that developed a fever and colic in the PO period after SI surgery were more likely to have a surgical reason for POR.

Clinical Significance: These findings may provide guidance for clinicians when they are making decisions about repeat celiotomy in horses with POR after SI surgery.