© 2015 Wichtg Publishing JVA ISSN 1129-7298 J Vasc Access 2015; 16 (5): 367-371 Original article Several studies over the last decade have confrmed that antbiotc catheter lock solutons are efectve in reducing the frequency of CRBSIs, but they may be associated with bacterial antbiotc resistance (4-11). Ethanol is a prom- ising catheter lock soluton, since it is an antseptc agent that demonstrates bactericidal actvites against both gram- positve and gram-negatve bacteria and fungal organisms. It works by protein denaturaton and thus development of resistance is not a concern (12). Its use as a sterilizing agent for hemodialysis catheters was frst described in 2006 (13) and a few studies since have evaluated the safety of such a soluton on the mechanical integrity of diferent types of peripheral and central lines. Since many dialysis patents undergo treatment using the same catheter for months or years, it is important to test the long-term efects of ethanol on both silicone- and polyurethane-based catheters. Crnich and colleagues evaluated 10 weeks of exposure in both polyurethane and silicone catheters to 70% ethanol in vitro. They suggested that both silicone-based and carb- othane-based catheters can maintain integrity afer ethanol DOI: 10.5301/jva.5000397 Efects of prolonged ethanol lock exposure to carbothane- and silicone-based hemodialysis catheters: a 26-week study Daniel L. Landry 1,2 , Randa A. Jaber 1,2 , Nandheesha Hanumanthappa 1,2 , George S. Lipkowitz 1,2 , Michael H. O’Shea 1,2 , Harry Bermudez 3 , Adam P. Hathorne 3 , Gregory L. Braden 1,2 1 Baystate Medical Center, Springfeld, MA - USA 2 Tufs University School of Medicine, Boston, MA - USA 3 University of Massachusets Polymer Science & Engineering, Amherst, MA - USA Introducton Central venous catheters (CVCs) remain the “Achilles heel” of hemodialysis, and are used in the majority of patents ini- tatng hemodialysis (1). However, vascular catheters remain potental sources of catheter-related bloodstream infectons (CRBSIs) and are associated with a 2- to 3-fold increased risk in mortality, and a 10- to 20-fold higher risk of bacteremia when compared to fstulas (2, 3). ABStRAct Purpose: Antbiotc locks in catheter-dependent chronic hemodialysis patents reduce the rate of catheter-relat- ed bloodstream infectons (CRBSIs), but may be associated with the development of resistant bacteria. Ethanol- based catheter locks may provide a beter alternatve; however, there are limited data on the long-term integrity of dialysis catheters exposed to ethanol. Methods: We performed in vitro testng of two types of hemodialysis catheters—silicone (SLC) and carbothane (CBT) based—with a 70% ethanol lock (EL) versus heparin lock (HL) for 26 weeks. Lock solutons were changed thrice weekly to mimic a conventonal hemodialysis schedule. We tested mechanical propertes of the catheters at 0, 13 and 26 weeks by examining stress/strain relatonships (SS400%) and modulus of elastcity (ME). Electron microscopy was performed to examine catheter ultrastructure at 0 and 26 weeks. Results: Catheter integrity for HL versus EL in SLC (SS400%: 4.5 vs. 4.5 MPa, p = NS; ME: 4.6 vs. 4.7 MPa, p = NS) or CBT-based catheters (SS400%: 7.6 vs. 8.9 MPa, p = NS; ME: 9.6 vs. 12.2 MPa, p = NS) were all similar at 13 and 26 weeks. Scanning electron microscopy revealed no structural changes in the central and luminal wall internal surfaces of EL- versus HL-treated catheters. conclusions: There were no signifcant diferences in catheter integrity between SLC or CBT catheters exposed to a 70% EL for 26 weeks. Given its low cost, potental to avoid antbiotc resistance and structural integrity afer 6 months of high-dose ethanol, ELs should be studied prospectvely against antbiotc locks to assess the efcacy and safety in hemodialysis patents. Keywords: Catheters, Ethanol, Hemodialysis, Lock Accepted: March 14, 2015 Published online: May 29, 2015 corresponding author: Daniel L. Landry, DO Division of Nephrology Baystate Medical Center 759 Chestnut Street Springfeld, MA 01107, USA daniel.landry@bhs.org