Effects of Prolonged Ethanol Lock Exposure to Carbothane- and Silicone-based Hemodialysis Catheters: A 26-week Study

Abstract

Purpose Antibiotic locks in catheter-dependent chronic hemodialysis patients reduce the rate of catheter-related bloodstream infections (CRBSIs), but may be associated with the development of resistant bacteria. Ethanol-based catheter locks may provide a better alternative; however, there are limited data on the long-term integrity of dialysis catheters exposed to ethanol. Methods We performed in vitro testing 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 solutions were changed thrice weekly to mimic a conventional hemodialysis schedule. We tested mechanical properties of the catheters at 0, 13 and 26 weeks by examining stress/strain relationships (SS400%) and modulus of elasticity (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 significant differences in catheter integrity between SLC or CBT catheters exposed to a 70% EL for 26 weeks. Given its low cost, potential to avoid antibiotic resistance and structural integrity after 6 months of high-dose ethanol, ELs should be studied prospectively against antibiotic locks to assess the efficacy and safety in hemodialysis patients.