title: Intra-articular pharmacokinetics of a gentamicin impregnated collagen sponge in the canine stifle: an experimental study.
abstract: OBJECTIVE
  To investigate local and systemic pharmacokinetics of gentamicin after intra-articular implantation of a gentamicin impregnated collagen sponge (GICS) in the inflamed canine joint.
  
  
  METHODS
  Descriptive repeated measures experimental study.
  
  
  METHODS
  Dogs (n = 9).
  
  
  METHODS
  Stifle joint inflammation was caused by urate injection. Twenty-four hours later a GICS (gentamicin dose, 6 mg/kg) was arthroscopically implanted. Synovial fluid and plasma gentamicin concentrations were measured for 14 days after implantation, and pharmacokinetic parameters modeled using statistical moment analyses.
  
  
  RESULTS
  Intra-articular gentamicin concentrations fell to sub-MIC for Staphylococcus sp. (4 µg/mL) by 22.4 hours (95% CI: 18.6-26.2) after sponge implantation. Cmax synovial was 2397 µg/mL (95%CI: 1161-3634 µg/mL) at 1.2 hours (95%CI: 0.5-1.8 hours). Plasma gentamicin concentrations achieved levels of Cmax plasma  = 8.0 µg/mL (95%CI: 6.1-10.0 µg/mL) at 1.5 hours (95%CI: 0.8-2.1) after GICS placement and fell below target trough of 2.0 µg/mL by 5.6 hours (95%CI: 4.7-6.5 hours) after GICS placement.
  
  
  CONCLUSIONS
  Intra-articular gentamicin concentration after GICS placement at an IV-equivalent dose reached high levels and declined rapidly. The maximum plasma levels attained were ∼1/3 of the recommended sub-toxic target for people after parenteral gentamicin administration.
authors.affiliation: Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada.
authors.forename: Galina M
authors.initials: GM
authors.lastname: Hayes
authors.forename: Thomas W G
authors.initials: TW
authors.lastname: Gibson
authors.forename: Noel M M
authors.initials: NM
authors.lastname: Moens
authors.forename: Beatriz
authors.initials: B
authors.lastname: Monteiro
authors.forename: Ron J
authors.initials: RJ
authors.lastname: Johnson
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics; D019540:Area Under Curve; D003094:Collagen / Q000737:chemistry*; D004285:Dogs; D004343:Drug Implants; D005260:Female; D005839:Gentamicins / Q000008:administration & dosage / Q000097:blood / Q000737:chemistry / Q000493:pharmacokinetics*; D006207:Half-Life; D008297:Male; D008826:Microbial Sensitivity Tests; D013210:Staphylococcus / Q000187:drug effects; D013582:Synovial Fluid / Q000378:metabolism; D013585:Synovitis / Q000139:chemically induced / Q000662:veterinary; D014527:Uric Acid / Q000633:toxicity
chemical_list: D000900:Anti-Bacterial Agents; D004343:Drug Implants; D005839:Gentamicins; D014527:Uric Acid; D003094:Collagen