1164. In vitro Antimicrobial Efficacy of Novel Antimicrobial Dacron Vascular Grafts in the Inhibition of Multidrug-Resistant Gram-Negative Biofilm

Abstract

BackgroundVascular graft infections can be a devastating complication in vascular reconstructive surgery. Management of these infections is highly invasive and includes excision of the graft, debridement of infected material, and in situ reconstruction. There is a need for additional strategies for infection prevention in graft surgeries. The minocycline + rifampin + chlorhexidine (MRCH) triple combination had been previously demonstrated to be effective against biofilm formation in central venous catheters. In this study, we evaluated in vitro effectiveness and durability of MRCH coated Dacron vascular grafts in inhibiting multidrug-resistant Gram-negative biofilm formation.MethodsDacron vascular grafts were coated with MRCH based on a proprietary method. Antimicrobial efficacy at baseline and 3-week durability was assessed using a well-established in vitro biofilm colonization model. Multidrug-resistant Gram-negative pathogens tested include CRE Escherichia coli (EC), MDR Pseudomonas aeruginosa (PS) and CRE Klebsiella pneumoniae (KB). Antimicrobial durability was assessed for grafts that had been eluting in serum for 3 weeks prior to testing. Baseline and 3-week grafts were quantitatively culture to enumerate any biofilm viable biofilm colonization. Uncoated Dacron grafts were used as controls.ResultsAt baseline and 3 weeks MRCH vascular grafts completely inhibited biofilm formation resulting in an 8-log10 reduction in bacterial colonization compared with uncoated grafts.ConclusionMRCH coated Dacron vascular grafts demonstrated in vitro effectiveness for at least 3 weeks in preventing biofilm colonization by multidrug-resistant Gram-negative pathogens. Further in vivo testing is warranted. Disclosures All authors: No reported disclosures.