Risk factors for septic peritonitis and failure to survive in dogs undergoing gastrointestinal (GI) surgery have been identified in previous reports. Dogs and cats that undergo multiple procedures are less likely to survive than those undergoing a single procedure. Presurgical diagnosis of septic peritonitis is also a negative prognostic factor. However, location of the surgical site (ie, small vs large intestine) does not appear to influence mortality. The association between preoperative hypoproteinemia and adverse outcomes is up for debate. This retrospective study evaluated risk factors for death and/or development of septic peritonitis following full-thickness GI incisions in 197 dogs at a veterinary teaching hospital from 1998 to 2007. The authors hypothesized that hypoalbuminemia, hypoproteinemia, and preoperative septic peritonitis would be associated with postoperative septic peritonitis and death. They also sought to identify other significant prognostic markers. They found a mortality of approximately 15% following various GI surgeries in dogs, and septic peritonitis was diagnosed after 12% of surgeries. Death was 3 times more likely in dogs that had septic peritonitis before surgery. Low albumin and low protein (both pre- and postoperatively) and presence of preoperative septic peritonitis were significantly associated with death and postoperative septic peritonitis. Hypotension during surgery, longer procedures, and concurrent extrahepatic biliary surgery were identified as significant risk factors as well. In contrast to other studies, the diagnosis of intestinal foreign body was found to be significantly protective.

Commentary: It makes intuitive sense that the prognosis for a dog undergoing GI surgery would be less favorable if the pet was already septic or had biochemical derangements, such as low protein or albumin. This study emphasizes the importance of fully evaluating each pet prior to surgery through CBC and serum biochemical studies, abdominal ultrasound, and abdominocentesis when peritoneal fluid is either visualized or suspected.—Heather Troyer, DVM, Diplomate ABVP

Identification of risk factors for septic peritonitis and failure to survive following gastrointestinal surgery in dogs. Grimes JA, Schmiedt CW, Cornell KK, Radlinksy MG. JAVMA 238:486-494, 2011.