Evaluation of intraosseous vs intravenous antibiotic levels in a porcine model.

OBJECTIVES

To compare intraosseous vs intravenous routes of administration and their effects on serum levels of four antibiotics in an animal model.

DESIGN

Prospective controlled study comparing two routes of drug administration.

SETTING

Research laboratories of a large pharmaceutical company.

PARTICIPANTS

Twenty male and female domestic swine weighing 10 to 20 kg.

INTERVENTIONS: The animals were anesthetized and treated with controlled ventilation. The animals were divided into one of four groups: (1) intravenous and intraosseous cefotaxime sodium (50 mg/kg), (2) intravenous and intraosseous chloramphenicol sodium succinate (25 mg/kg), (3) intravenous and intraosseous vancomycin hydrochloride (15 mg/kg), or (4) intravenous and intraosseous tobramycin sulfate (2.5 mg/kg). There was a 24-hour clearance period for groups 1 and 2 and a 48-hour clearance period for groups 3 and 4. Serum drug levels were measured at 1, 15, 30, 45, 60, 90, and 120 minutes after intravenous and intraosseous administration of the respective antibiotics. Control and treated tibias were sampled for drug levels at the end of the experiment.

MEASUREMENTS AND MAIN

RESULTS

- Peak serum concentrations for intravenously administered antibiotics were within the therapeutic range. Peak serum levels after intravenous and intraosseous administration were 102 and 82 mg/L, respectively for cefotaxime; 13.9 and 6.3 mg/L, respectively, for chloramphenicol; 24.5 and 3.8 mg/L, respectively, for vancomycin; and 7.1 and 1.3 mg/L, respectively, for tobramycin.

CONCLUSIONS

Cefotaxime may be administered intraosseously when intravenous access is not possible. We cannot recommend chloramphenicol or vancomycin for intraosseous administration, because serum levels were not comparable with those following intravenous administration. Findings with tobramycin suggested a lack of achievement of serum levels comparable with those following intravenous administration.