EFFICACY OF VANCOMYCIN TRI-IODODECYCLEMETHYL AMMONIUM CHLORIDE-COATEDVENTRICULOSTOMY CATHETERS IN REDUCING INFECTION/

OBJECTIVE: The biotoxicity of tri-iododecyclemethyl ammonium chloride (TDMAC)-coated catheters in the brain was tested, as was the efficacy of the vancomycin-bonded, TDMAC-coated catheters to inhibit staphyloco ccal growth in vitro and to delay the onset of clinical manifestations of catheter-related staphylococcal ventriculitis in a rabbit experime ntal model. METHODS: The brain toxicity of the TDMAC-coated catheters was tested in New Zealand White rabbits. The efficacy of the vancomyci n-bonded, TDMAC-coated catheters in the inhibition of staphylococcal g rowth was tested in agar seeded with Staphylococcus aureus and Staphyl ococcus epidermidis strains. Sections of vancomycin-bonded, TDMAC-coat ed catheters were placed in saline solution for testing of drug releas e over time. Stereotactic placement of ventriculostomy catheters was p erformed in two groups of New Zealand White rabbits. In the experiment al group, vancomycin-bonded, TDMAC-coated catheters were used, In the control group, TDMAC-coated catheters were used. Staphylococcal coloni es were inoculated at the exit site of the catheters. Culture of the c atheter tips was performed at the time of death of the animals. RESULT S: No toxic reactions were seen at the implantation sites or in surrou nding brain. Significant inhibition of growth of both S. aureus and S. epidermidis was noted with the vancomycin-bonded catheters (P = 0.01) . Vancomycin continued to be released from catheters for the full 6 da ys of the study. The median interval to development of clinical manife stations of ventriculitis among the experimental group of rabbits was 53 days; among the control group, the interval was 27 days (P < 0.001) . CONCLUSION: Vancomycin-bonded, TDMAC-coated ventriculostomy catheter s bind and release the drug at levels exceeding the minimum inhibitory concentration for S. aureus and S. epidermidis for at least 6 days an d can significantly delay the onset of infectious ventriculitis in a r abbit model.