Alteplase versus urokinase for occluded hemodialysis catheters.

Background: The use of central venous catheters as a source of vascular access in patients undergoing hemodialysis may be complicated by thrombosis. Frequently, thrombolytics are used in an attempt to reestablish blood flow through partially or completely occluded catheters.

Objective: To compare the efficacy of alteplase (recombinant tissue plasminogen activator) versus urokinase in reestablishing adequate blood flow through partially or completely occluded vascular catheters.

Methods: Part 1 of the study prospectively investigated the effect of alteplase in reestablishing adequate blood flow through partially or completely occluded vascular catheters in 30 hemodialysis patients. Part 2 of the trial compared the efficacy of alteplase with that of urokinase in 14 of 30 patients who had also previously received urokinase. A 30-minute push-protocol was used to administer thrombolytics in both parts of the study. The primary endpoint was the proportion of patients with partially or completely occluded catheters achieving post-thrombolytic blood flow of > or =200 mL/min.

Results: Part 1 showed a large proportion of partially or completely occluded catheters achieving post-alteplase blood flows > or =200 mL/min (70/76, 92.1% vs. 34/40, 85%, respectively). In Part 2 of the study, the proportion of partially occluded catheters achieving post-thrombolytic blood flows > or =200 mL/min was not significantly different between the alteplase and urokinase groups, (36/41, 87.8% vs. 21/28, 75%, respectively; p = 0.205). The proportion of completely occluded catheters achieving post-thrombolytic blood flows > or =200 mL/min was significantly better with alteplase compared with urokinase (15/17, 88.2% vs. 6/14, 42.8%, respectively; p =.018).

Conclusions: Alteplase, administered via the 30-minute push-protocol, is an effective thrombolytic for restoring hemodialysis catheter patency. In our study sample, alteplase was generally more effective than urokinase in restoring blood flow through catheters, especially those that were completely occluded.