Profilaxis pre-quirúrgicas en perras, mediante el uso de cefalotina y evaluación de su eficacia basándose en índices farmacocinéticos-farmacodinámicos

Abstract

Cephalothin (CFL) is a cephalosporin indicated for preoperative prophylaxis in dogs, especially in elective surgery where asepsis can be done comprehensively. Current clinical recommendations state that the antimicrobial should be administered 30 to 60 minutes before the surgical incision, in order to achieve adequate tissue concentrations. Moreover, the surgical procedures more than two antimicrobial elimination half-lives are extended, another dose should be administered to guarantee bactericidal concentrations in tissues. The pharmacokinetic/pharmacodynamic (PK/ PD) to beta-lactams, recommends efficacy parameter t>MIC, between 50 and 80% of the dosing interval to achieve adequate antimicrobial efficacy. No pharmacokinetic studies of CFL in dogs undergoing surgery consider analysis PK / PD and that both anesthesia and the surgical procedure may modify the distribution and / or elimination of the antimicrobial. The aim of this study was to evaluate the pharmacokinetics of the CFL in dogs undergoing ovariohysterectomy (G2) and compared with a control group not subjected to ovariohysterectomy (G1); on the other hand determine the MIC of this antimicrobial against native strains of Staphylococcus spp. to establish antimicrobial efficacy parameters t>MIC to provide a basis regimens. Three experimental stages were used. In the first, CFL pharmacokinetics was studied in dogs following intravenous administration at single dose of 25 mg / kg; there the concentration-time CFL in G1 and G2 profiles were compared. Antimicrobial concentrations were measured in serum and skin, further for G2, in subcutis, muscle and peritoneum. The second stage was carried out based on a pharmacodynamic study dermal Staphylococcus spp. isolates from healthy animals and determination of their MIC. Finally, in the third stage calculating PK/PD parameters for serum and tissue CFL, with the dosage given in patients undergoing surgical procedures it was performed ...