Recombinant tissue plasminogen activator infusion for hemodialysis catheter clearance

Hemodialysis (HD) catheter occlusion is a common cause of poor blood flow and inadequate dialysis. In order to address this problem in our pediatric dialysis unit, we elected to use short (2-h) infusions of low-dose recombinant tissue plasminogen activator (rtPA) for thrombolysis of occluded catheters. Catheters meeting diagnostic criteria for thrombosis were infused with 2.5 mg rtPA in 25 ml 0.9 normal saline over 2 h prior to dialysis. Retrospective data collection was carried out to assess the success of this procedure. Variables assessed included blood flow (Qb), transmembrane pressure (TMP) and venous pressure (VP) before and after rtPA infusion. Seven catheter thromboses in six patients were successfully treated with rtPA; there were significant improvements in Qb (p <0.01), TMP (p <0.01), and VP (p <0.02). At 32 weeks after rtPA therapy, Kaplan-Meier survival analysis showed a 60% probability of primary catheter patency. At the end of the study, 85% of catheters had adequate function as defined by a Qb >200 ml/min. No adverse events were observed. Low-dose rtPA infusion is safe and effective for catheter thrombolysis in outpatient pediatric HD patients. It may serve as an alternative method of administration to local instillation and may be used to restore patency before resorting to surgical revisions.