Impact of appropriate empirical antimicrobial therapy on outcome of dogs with septic peritonitis

Objective To determine whether appropriate empirical antimicrobial therapy influenced survival in dogs with septic peritonitis. Design Retrospective case series (2003–2011). Setting University teaching hospital. Animals Eighty‐six dogs with cytological confirmation or positive bacterial culture of abdominal sepsis and subsequent surgical intervention. Interventions None. Measurement and Main Results Forty‐nine of 86 dogs (57%) survived to hospital discharge. Thirty‐seven of 86 dogs were classified as having ‘‘abdominal infection,’’ 31/86 as ‘‘severe sepsis,’’ and the remaining 18/86 as in ‘‘septic shock.’’ Mortality was greatest in the ‘‘septic shock’’ category (94%). Empirical antimicrobial treatments were appropriate in 41/78 dogs (52.6%). Appropriateness was not associated with treatment outcome overall or when compared between sepsis severity groups. Antimicrobials had been given in the 30 days before admission in 63/86 (73.3%) dogs. Prior therapy with antimicrobials showed no association with outcome ( P = 0.512) but was associated with subsequent inappropriate empirical antimicrobial selection ( P = 0.031). Recent abdominal surgery was associated with subsequent inappropriate empirical antimicrobial selection ( P = 0.021). Conclusions In this population, appropriateness of empirical antimicrobial choice was not associated with survival to discharge. Previous antimicrobial administration or abdominal surgery was associated with subsequent inappropriate empirical antimicrobial selection.