Background: The risk of catheter-related infection or bacteremia, with initial and extended use of femoral versus nonfemoral sites for double-lumen vascular catheters (DLVCs) during continuous renal replacement therapy (CRRT), is unclear. Study Design: Retrospective observational cohort study. Setting Participants: Critically ill patients on CRRT in a combined intensive care unit of a tertiary institution. Factor: Femoral versus nonfemoral venous DLVC placement. Outcomes: Catheter-related colonization (CRCOL) and bloodstream infection (CRBSI). Measurements: CRCOL/CRBSI rates expressed per 1,000 catheter-days. Results: We studied 458 patients (median age, 65 years; 60 males) and 647 DLVCs. Of 405 single-site only DLVC users, 82 versus 18 received exclusively 419 femoral versus 82 jugular or subclavian DLVCs, respectively. The corresponding DLVC indwelling duration was 6 ? 4 versus 7 ? 5 days (P = 0.03). Corresponding CRCOL and CRBSI rates (per 1,000 catheter-days) were 9.7 versus 8.8 events (P = 0.8) and 1.2 versus 3.5 events (P = 0.3), respectively. Overall, 96 patients with extended CRRT received femoral-site insertion first with subsequent site change, including 53 femoral guidewire exchanges, 53 new femoral venipunctures, and 47 new jugular/subclavian sites. CRCOL and CRBSI rates were similar for all such approaches (P = 0.7 and P = 0.9, respectively). On multivariate analysis, CRCOL risk was higher in patients older than 65 years and weighing >90 kg (ORs of 2.1 and 2.2, respectively; P <0.05). This association between higher weight and greater CRCOL risk was significant for femoral DLVCs, but not for nonfemoral sites. Other covariates, including initial or specific DLVC site, guidewire exchange versus new venipuncture, and primary versus secondary DLVC placement, did not significantly affect CRCOL rates. Limitations: Nonrandomized retrospective design and single-center evaluation. Conclusions: CRCOL and CRBSI rates in patients on CRRT are low and not influenced significantly by initial or serial femoral catheterizations with guidewire exchange or new venipuncture. CRCOL risk is higher in older and heavier patients, the latter especially so with femoral sites.