Comparison of the palindrome vs. step-tip tunneled hemodialysis catheter: a prospective randomized trial.

Numerous designs for tunneled hemodialysis catheter have been developed in an effort to improve catheter function and survival. In this prospective randomized controlled study, 97 patients were randomized into the palindrome catheter group (PC, n = 47) and step-tip catheter group (SC, n = 50). Demographic characteristics were not different between the two groups. The effective blood flow rates at different pump speeds were comparable between the two groups. The recirculation was low within acceptable range in both types of catheter, and hemodialysis adequacy was not different between the two groups. However, when arterial and venous blood lines were reversed, while the recirculation was significantly increased in SC, it was not increased at all in PC. The catheter dysfunction-free survival rate was significantly higher in PC than in SC (78.9% vs. 54.4% at 2 months, p = 0.008). The overall catheter survival rate was also higher in PC than in SC (90.6% vs. 68.8% at 2 months, p = 0.015). We conclude that both catheters are equally effective on the adequate hemodialysis and low recirculation. However, the PCs have advantages over the SCs in terms of lower catheter dysfunction rate, lower recirculation with reversed blood lines, higher short-term catheter survival rate.