ABSTRACT
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 an
in 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-resistant
Staphylococcus aureus
(MRSA),
Staphylococcus epidermidis
,
Escherichia coli
,
Pseudomonas aeruginosa
, and
Candida 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
, and
C. albicans
biofilms (
P
< 0.0001). Furthermore, CHX-M/R CVCs were superior to M/R CVCs against
P. aeruginosa
and
C. albicans
(
P
= 0.003) and were superior to CHX/SS CVCs against MRSA and
P. 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 and
Candida
.