Prevention of Transmission of Multidrug-Resistant Organisms during Catheter Exchange using Antimicrobial Catheters

Exchanging a central venous catheter (CVC) over a guide wire for a fresh uncoated CVC in the presence of bacteremia can result in cross-infection of the newly exchanged CVC. A recent retrospective clinical study showed that exchanging a catheter over a guide wire in the presence of bacteremia using an antimicrobial minocycline-rifampin (M/R) catheter may improve outcomes. To expand on this, we developed anin vitro cross-contamination model of exchange to evaluate the efficacy of different antimicrobial CVCs in preventing cross-contamination of multidrug-resistant organisms during exchange. Uncoated CVCs were allowed to form biofilm by methicillin-resistantStaphylococcus aureus (MRSA),Staphylococcus epidermidis ,Escherichia coli ,Pseudomonas aeruginosa , andCandida albicans . After 24 h, the biofilm-colonized CVCs were placed in a glass tube containing bovine calf serum plus Mueller-Hinton broth, and each catheter was exchanged over a guide wire for a fresh uncoated or an M/R-, chlorhexidine-silver sulfadiazine (CHX/SS)-, or chlorhexidine-M/R (CHX-M/R)-coated CVC. Cross-contamination of exchanged catheters was enumerated by sonication and quantitative plating methods. The exchange of M/R CVCs completely prevented cross-contamination by MRSA biofilms compared to control exchanged CVCs (P < 0.0001). Exchange with CHX/SS CVCs reduced but did not completely prevent cross-contamination by MRSA (P = 0.005). Exchange with CHX-M/R CVCs completely prevented cross-contamination by MRSA,P. aeruginosa , andC. albicans biofilms (P < 0.0001). Furthermore, CHX-M/R CVCs were superior to M/R CVCs againstP. aeruginosa andC. albicans (P = 0.003) and were superior to CHX/SS CVCs against MRSA andP. aeruginosa (P = 0.01). In conclusion, exchange with the novel CHX-M/R CVC was the only exchange effective in completely and concurrently preventing cross-contamination from bacteria andCandida .