Pulmonary administration of perfluorodecaline-gentamicin and perfluorodecaline-vancomycin emulsions

The aim of this study was to examine pharmacokinetics and pulmonary antibio tic tissue concentrations (PATC) of gentamicin and vancomycin after intrapu lmonary administration of a perfluorodecaline (PFD)-gentamicin and a PFD-va ncomycin emulsion during partial liquid ventilation (PLV). PLV was initiate d in 19 healthy rabbits and 18 surfactant-depleted rabbits. The animals wer e randomized to receive either 5 mg/kg gentamicin and 15 mg/kg vancomycin i ntravenously, or 5 mg/kg gentamicin intrapulmonary, or 15 mg/kg vancomycin intrapulmonary. Antibiotic plasma levels were measured after 15, 30, 45, an d 60 min, and hourly thereafter. After 5 h animals were sacrificed and lung s were removed to evaluate PATC and histology. PATC were significantly high er after intrapulmonary administration of both gentamicin and vancomycin. I n healthy rabbits, peak plasma concentrations were lower and 5 h plasma con centrations were higher after intrapulmonary administration, whereas plasma concentrations were not different in surfactant-depleted rabbits. There we re no differences in lung histology, hemodynamics, lung mechanics, or gas e xchange between the treatment groups. We conclude that during PLV, higher P ATC can be achieved after intrapulmonary administration of PFD-antibiotic e mulsions compared with intravenous administration of the same dose without apparent short-term adverse effects. We speculate that intrapulmonary antib iotic administration during PLV may be beneficial in treating severe pneumo nia.