Study Examines Performance of Tunneled Cuffed Catheters

A high rate of infection and thrombus-related dysfunction are complications associated with long-term use of tunneled cuffed catheters for hemodialysis. The NKF-KDOQI (National Kidney Foundation-Kidney Disease Outcomes Quality Initiative) clinical guidelines discourage use of tunneled cuffed catheters due to the risk of infection, thrombosis, and fibrin sheath formation that may cause inadequate and/or irregular blood flow rates and the risk of damaging large central veins.

However, due perhaps to documented inadequate vascular access anatomy or as a bridge to a functional native fistula or recovery of kidney failure, tunneled cuffed catheters are still used frequently in the hemodialysis population.

According to Hans Van Der Meersch, MD, and colleagues, specific mechanical features of tunneled cuffed catheters may improve hemodynamic performance and decrease thrombosis and infection rates. The researchers conducted a single-center randomized clinical trial to determine whether there is an advantage of one design over another.

The study was designed to assess (1) infection- and thrombosis-free catheter survival and (2) rheologic performance of the Palindrome catheter, with a symmetrical tip and laser-cut side slots, compared with the HemoStar catheter, with a 3-cm staggered tip and standard making-punched distal side holes. Study results were reported in the American Journal of Kidney Diseases [2014;64(6):902-908].

The study intervention was use of the Palindrome Symmetric Tip Dialysis Catheter or HemoStar Long-Term Hemodialysis Catheter. The study’s primary end point was primary assisted patency. Secondary end points included incidence of catheter-related bloodstream infection (CRBSIs), thrombosis, and two indicators of rheologic function (mean effective blood flow rate and urokinase use).

The study included data on 302 tunneled cuffed catheters (Palindrome, 151; HemoStar 151) used in 239 hemodialysis patients (Palindrome as first or only catheter, 118; HemoStar as first or only catheter, 121). The same patient could be recruited more than once. The two groups were similar in baseline clinical characteristics.

The analysis included a total of 41,127 catheter-days (Palindrome, 20,552; HemoStar, 20,605). Mean follow-up was 135.2 days. The study catheter was the first catheter in 239 of the study participants; the remaining 63 participants had a history of one or more catheters.

The catheter was removed electively in 139 participants; reasons for removal were recovery of kidney function, transfer to peritoneal dialysis therapy, or maturation of the native arteriovenous fistula. Ninety participants dropped out of the study due to death, kidney transplantation, transfer to another center, or accidental removal or damage to the catheter.

Mean primary assisted patency was 135.9 days for the Palindrome catheter and 136.5 days for the HemoStar catheter. Following censoring for catheter design-unrelated removal, catheter survival at 6, 12, and 24 months was 77.3%, 72.0%, and 71.3% for the Palindrome and 87.8%, 84.0%, and 76.4% for the HemoStar. There was no significant difference in survival between catheter types.

In 10 patients (6.6%), the catheter was removed due to infection in patients with a Palindrome catheter, resulting in a total infection rate of 0.48/1000 catheter days. Removal for infection was done in three patients (2%) with a HemoStar catheter, resulting in a total infection rate of 0.14/1000 catheter days (P=.09). When only definite CRBSIs were considered, five catheters in the Palindrome group and 2 in the HemoStar group were removed, resulting in a CRBSI rate of 0.24/1000 catheter days and 0.10/1000 catheter days, respectively (P=.05).

Eleven patients (7.3%) in the Palindrome group required removal for thrombosis that could not be resolved with thrombolysis; nine patients (6.0%) in the HemoStar group required removal, resulting in thrombosis rates of 0.53/100 and 0.43/1000 catheter days, respectively (P=.08).

In the Palindrome group, urokinase use was significantly lower than in the HemoStar group, as evidenced by a lower number of urokinase infusions per 1000 catheter days (17 and 35, respectively; P<.001) and higher number of catheters that never required a urokinase infusion (88 vs 68, respectively; P=.03). There was no difference between the groups in time to first urokinase infusion. Finally, mean effective blood flow rate was significantly higher in the Palindrome group compared with the HemoStar group (333.1 vs 308.3 mL/min, respectively; P<.001).

The researchers said the primary study limitation was that investigators and dialysis nurses were not blinded to catheter assignment.

“In conclusion, urokinase use was lower and blood flow rates were higher for Palindrome catheter, but catheter survival and removal for thrombosis and infection were very low compared with data in the literature and were similar for both catheters. Although mechanical catheter design can slightly improve catheter rheology, it has little if any influence on catheter survival and complications such as thrombosis and infection, A composite of other measures, including early use of a mechanical catheter dysfunction salvage protocol, disinfection protocols, type of catheter lock, nurse and patient education, and eradication of S aureus nasal carriage, may be more important in reducing the rates of thrombosis and infection of tunneled cuffed catheters,” the researchers said.

Takeaway Points

  1. This trial was designed to compare the design and performance of two tunneled cuffed catheters: the Palindrome and the HemoStar.
  2. The researchers aimed to assess the infection- and thrombosis-free catheter survival and rheologic performance of the two catheters.
  3. Primary assisted patency and the incidence of infection and thrombosis were similar for both catheter types.