Effect of perioperative prophylactic antimicrobial treatment in dogs undergoing elective orthopedic surgery

Objective-To determine whether perioperative antimicrobial prophylaxis woul d reduce incidence of postoperative infection among dogs undergoing electiv e orthopedic procedures. Design-Randomized, controlled, blinded, intention clinical trial. Animals-Dogs of any breed, sex, or age undergoing elective orthopedic surge ry at a veterinary leaching hospital. Procedures-Dogs were randomly assigned to 1 of 3 groups: treatment with sal ine solution, treatment with potassium penicillin G, and treatment with cef azolin. Treatments were intended to be administered within 30 minutes prior to surgery; a second dose was administered if surgery lasted > 90 minutes. Dogs were monitored for 10 to 14 days after surgery for evidence of infect ion. Results-After the first 112 dogs were enrolled in the study, it was found t hat infection rate for control dogs (5/32 dogs) was significantly higher th an the rate for dogs treated with antimicrobials (3/80 dogs). Therefore, no more dogs were enrolled in the study. A total of 126 dogs completed the st udy. Monte Carlo simulations indicated that compared with dogs that receive d antimicrobials prophylactically, dogs that received saline solution devel oped infections significantly more frequently. Difference in efficacy, howe ver, was not observed between the 2 antimicrobial drugs used. Conclusions and Clinical Relevance-Results indicated that perioperative ant imicrobial prophylaxis decreased postoperative infection rate in dogs under going elective orthopedic surgery, compared with infection rate in control dogs. Cefazolin was not more efficacious than potassium penicillin G in the se dogs.