Comparison of 2 techniques for regional antibiotic delivery to the equine forelimb: intraosseous perfusion vs. intravenous perfusion

The purpose of this study was to compare the synovial fluid concentrations and pharmacokinetics of amikacin in the equine limb distal to the carpus fo llowing intraosseous and intravenous regional perfusion. The front limbs of 6 horses were randomly assigned to either intraosseous or intravenous perf usion. A tourniquet was placed distal to each carpus and the limb perfused with 500 mg of amikacin. Systemic blood samples and synovial fluid samples were collected over 70 min from the distal interphalangeal (DIP) joint, met acarpophalangeal joint, and digital flexor sheath. The tourniquet was remov ed following the 30 min sample collection. The mean peak amikacin concentra tion for the DIP joint was significantly higher with intravenous perfusion. There were no significant differences in time to peak concentration or eli mination half-life between methods at each synovial structure. Each techniq ue produced mean peak concentrations ranging from 5 to 50 times that of rec ommended peak serum concentrations for therapeutic efficacy.