Perioperative ventricular arrhythmias are increased with hemoperitoneum and are associated with increased mortality in dogs undergoing splenectomy for splenic masses.

OBJECTIVE:To identify risk factors for intra- and postoperative ventricular arrhythmias (VAs) and in-hospital mortality in dogs undergoing splenectomy for splenic masses. ANIMALS:308 dogs. METHODS:Records from 2010 through 2018 were reviewed for dogs undergoing splenectomy for a splenic mass. Clinical and laboratory findings on admission, diagnostic imaging, anesthesia, surgery and pathology reports, treatment records, and in-hospital mortality were evaluated with logistic regression. RESULTS:VAs occurred in 138 (44.8%) dogs (126/308 [40.9%] postoperative, 51/308 [16.6%] intraoperative, 26/308 [8.4%] preoperative), with 50/308 (16.2%) dogs having more than one type of VA. Increasing heart rate and body weight, decreasing PCV and platelet count, hemoperitoneum, receipt of a transfusion, and diagnosis of hemangiosarcoma were associated with the presence of intra- and postoperative VAs on univariable analysis (all P < .001). On multivariable analysis, hemoperitoneum (P < .001 , < .001), increasing body weight (P = .026, < .001), and increasing heart rate (P = .028, < .001) were significant for intra- and postoperative VAs, respectively. Twenty dogs died (20/308 [6.5%]; 14/138 [10.1%] with VAs, 6/170 [3.5%] without VAs). Intra- and postoperative VAs were associated with in-hospital mortality (P = .009, .025, respectively). CLINICAL RELEVANCE:Perioperative VAs were common and odds of VAs were increased with hemoperitoneum, increasing heart rate, and increasing body weight. Presence of VAs increased the odds of in-hospital mortality. Despite this, the overall in-hospital mortality rate was low (6.5%), indicating a good prognosis for survival of surgery in dogs with splenic masses, regardless of the presence of VAs or hemoperitoneum.