Trial to Compare 1.0 Versus 2.0 mg Alteplase (tPA) Dosing in Restoring Hemodialysis Catheter Function

Hemodialysis is a procedure that kidney physicians perform when the kidneys fail and can no longer clean the blood and remove extra fluid and toxins from the body. Hemodialysis therefore requires access to reach the blood through either a surgically created permanent fistula or graft or through the insertion of a temporary catheter in one of the large body veins. While the use of fistulas or grafts is preferred because they are permanent, there may be conditions that prevent patients from having them and a hemodialysis catheter may be used instead. The problem with the use of catheters however is that they can become blocked due to the formation of blood clots. Kidney physicians try to resolve occlusion of hemodialysis catheters by injecting a medication called Alteplase which breaks the clot at the catheter site. There is no consensus in the medical community as to how much of the medication should be injected at the occluded catheter site. While some kidney physicians and studies recommend the use of 1.0 mg of the medication at each occlusion site, others recommend that 2.0 mg of the medication should be used. Thus, the purpose of this randomized clinical trial is to compare the effectiveness of 1.0mg versus 2.0mg dose of alteplase in resolving blood clots in hemodialysis catheters. The investigators will recruit patients for the study from a regional hemodialysis unit that is located in southwestern Ontario. Patients who agree to participate in this research and experiences occlusion of their hemodialysis catheters will be divided into two groups; making sure that this division is completely by chance. The first group will receive 1.0mg alteplase, while the second will receive 2.0mg Alteplase. The investigators will collect information on both groups and will run statistical analysis of these information to compare the results of clot resolution between the groups.