A novel antimicrobial central venous catheter impregnated with benzalkonium chloride

Abstract
Catheter-related sepsis is a common complication associated with the use of central venous catheters (CVC). In an attempt to overcome this problem benzalkonium chloride was incorporated into a CVC polymer. The effect of the presence of benzalkonium chloride on microbial colonization of the CVC was then assessed in vitro. MICs and MBCs of benzalkonium chloride for a range of organisms were performed and good activity against Gram-positive organisms was confirmed. In order to assess the antimicrobial activity of the benzalkonium-chloride-impregnated catheter, 2 cm lengths were placed on to nutrient agar plates inoculated with various micro-organisms. Zones of inhibition against five strains of Staphylococcus epidermidis and two strains of Staphylococcus aureus were demonstrated. Smaller zones of inhibition was also produced with Gram-negative species and Candida albicans. The zone sizes correlated with the MICs. Bacterial adherence to the benzalkonium-chloride-impregnated catheters was determined in both static and dynamic models and was significantly reduced compared with control catheters, containing no antimicrobial agent (P < 0.01). Inhibition of microbial adherence to benzalkonium-chloride-impregnated catheters placed in 25% human blood in phosphate-buffered saline (PBS), for up to seven days or PBS alone for 14 days was detected. The findings indicate that benzalkonium-chloride-impregnated catheters exhibit reduced microbial colonization by a range of organisms in vitro. The incorporation of benzalkonium chloride into a CVC may thus offer an effective method for the prevention of catheter related sepsis.