title: Penetration of piperacillin into the vitreous after intravenous administration.
abstract: OBJECTIVE
  Penetration of piperacillin into the vitreous cavity after intravenous administration was investigated in humans.
  
  
  METHODS
  Forty-five eyes undergoing vitrectomy between November 1993 and December 1994 were included. Each patient received a single intravenous dose of piperacillin 4 g 2 hours before ocular incision. A 0.2-mL vitreous sample was aspired at the beginning of vitrectomy, a blood sample was obtained, and piperacillin level was assessed.
  
  
  RESULTS
  There were no detectable drug concentrations in 25 eyes. Mean vitreous drug concentration in the remaining evaluable eyes (n = 14) was 2.33 microg/mL (+/-0.76). We divided samples into two groups: 23 uninflamed (Group 1) and 16 inflamed (Group 2) eyes. Mean vitreous drug concentration was 0.42 microg/mL in Group 1 and 4.95 microg/mL in Group 2 (P < 0.2). Piperacillin concentration was higher than the minimum inhibitory concentration for gram-positive bacteria in 13% of uninflamed and 69% of inflamed eyes (P < 0.001).
  
  
  CONCLUSIONS
  Studies show that intravenously administered piperacillin can penetrate the vitreous cavity in rabbits. Our study suggests that a single dose of piperacillin can produce intravitreal concentrations sufficient to kill gram-positive bacteria in inflamed eyes. The poor intraocular penetration of systemically administered piperacillin in uninflamed eyes raises questions about its usefulness as a prophylactic agent in ophthalmic surgery.
authors.affiliation: Department of Ophthalmology, CHRU Morvan, Brest, France.
authors.forename: A
authors.initials: A
authors.lastname: Robinet
authors.forename: M A
authors.initials: MA
authors.lastname: Le Bot
authors.forename: J
authors.initials: J
authors.lastname: Colin
authors.forename: C
authors.initials: C
authors.lastname: Riche
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D005129:Eye Foreign Bodies / Q000378:metabolism / Q000601:surgery; D015818:Eye Infections, Bacterial / Q000382:microbiology / Q000517:prevention & control; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D007906:Lens Subluxation / Q000378:metabolism / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010406:Penicillins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D010878:Piperacillin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D012164:Retinal Diseases / Q000378:metabolism / Q000601:surgery; D012189:Retrospective Studies; D014821:Vitrectomy; D014822:Vitreous Body / Q000378:metabolism* / Q000601:surgery; D014823:Vitreous Hemorrhage / Q000378:metabolism / Q000601:surgery
chemical_list: D010406:Penicillins; D010878:Piperacillin