Heparin Versus Lepirudin Flushes in Preventing Blockage of Venous Access Devices

Summary

This study will compare the effectiveness of two blood thinners, heparin and lepirudin, in preventing withdrawal occlusion (blockage) in a venous access device (VAD). A VAD is a catheter (plastic tube) placed in a vein beneath the collarbone to deliver medication and withdraw blood samples during treatment. The device may become clogged, possibly by formation of a clot around the tip, blocking its opening and making it difficult or impossible to use. The clot can be dissolved by a medication called tPA. The blood thinner heparin has been used for many years to try to prevent the blockage from occurring, but it is still a problem in as many as 25 percent of VADs. This study will test whether a new blood thinner called lepirudin is more effective than heparin in preventing withdrawal occlusion caused by a small clot. Patients 21 years of age and older who are enrolled in NIH protocols at the Clinical Center and who require tunneled, open-ended VADs for their medical care may be eligible for this study. Candidates must expect to receive all of their primary medical care at the Clinical Center during the first 4 weeks after their VAD is inserted and most of their care at the Clinical Center for the next 3 months. Participants will be randomly assigned to receive either heparin or lepirudin flushes for the first 3 or 4 weeks after placement of their VAD-the period during which withdrawal occlusion is most likely to occur. After this period, all patients will use routine heparin flushes until the VAD is removed. The patient's VAD will be closely monitored for withdrawal occlusion during the 3- to 4-week test period and will continue to be observed for up to 3 months to check for lasting effects of the blood thinner.

Timeline

Start

2002-05

Primary completion

—

Completion

2006-04

Publications

• Background Raad II, Luna M, Khalil SA, Costerton JW, Lam C, Bodey GP. The relationship between the thrombotic and infectious complications of central venous catheters. JAMA. 1994 Apr 6;271(13):1014-6.
• Background Xiang DZ, Verbeken EK, Van Lommel AT, Stas M, De Wever I. Composition and formation of the sleeve enveloping a central venous catheter. J Vasc Surg. 1998 Aug;28(2):260-71. doi: 10.1016/s0741-5214(98)70162-4.
• Background Holcombe BJ, Forloines-Lynn S, Garmhausen LW. Restoring patency of long-term central venous access devices. J Intraven Nurs. 1992 Jan-Feb;15(1):36-41.

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