Objective: To evaluate risk factors for postoperative intestinal dehiscence, adjusting for potential confounders identified through directed acyclic graphs (DAGs).
Methods: A retrospective cohort study was conducted of dogs undergoing small intestinal surgery at a private referral center between July 2011 and July 2024. Directed acyclic graphs were used to identify risk factors, confounders, and mediators, with regression models developed to adjust for these confounders.
Results: A total of 55 dogs were included in the study. Of these, 11 dogs (20%) developed postoperative intestinal dehiscence. After adjusting for the time from clinical signs to surgery and the reason for surgery, dogs with preoperative septic peritonitis (PSP) had higher odds of dehiscence compared to those without PSP (OR, 40.7; 95% CI, 4.4 to 2,142). After adjusting for PSP, dogs with hypotensive events during hospitalization had higher odds of dehiscence compared to those without hypotension (OR, 15.6; 95% CI, 1.2 to 975). Additionally, dogs undergoing surgery for foreign body removal had lower odds of experiencing postoperative intestinal dehiscence compared to those with other reasons for surgery (OR, 0.2; 95% CI, 0.0 to 0.9). Serum albumin concentration, enterectomy, and vasopressor use were not independently associated with dehiscence.
Conclusions: DAGs identified multiple risk factors for dehiscence, along with potential confounders and mediators. Regression analysis confirmed that PSP, hypotensive events, and surgery type were independent risk factors for postoperative dehiscence.
Clinical relevance: Close monitoring of dogs with PSP and careful blood pressure management may help reduce the risk of postoperative dehiscence.
Keywords: anastomotic leak; enterectomy; hypoalbuminemia; hypotension; septic peritonitis.