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.