Warfarin Versus Aspirin in Preventing Tunneled Hemodialysis Catheter Thrombosis: A Prospective Randomized Study

Abstract

Vascular access complications are the greatest cause of morbidity and hospitalization in hemodialysis patients. The most frequent complication of central catheters used for hemodialysis is dysfunction due to thrombosis. Tunneled hemodialysis catheter thrombosis represents a major medical and economic burden. Although systemic anticoagulation is commonly prescribed to prevent thrombosis and malfunction of the vascular access during hemodialysis, there are only limited data regarding the effect of systemic anticoagulation or antiplatelet activation in between dialysis sessions. This randomized prospective study aimed to evaluate whether anticoagulation with adjusted-dose warfarin or low dose aspirin is associated with a long-term improvement of tunneled hemodialysis catheter thrombosis outcome. Among the 58 patients included in the study, 20 were placed on daily warfarin and 19 on aspirin, while 19 were used as control. Among patients receiving warfarin, 18 (90%) achieved adequate anticoagulation (i.e. INR value within target range), and four (20%) had at least one episode of catheter malfunction due to catheter thrombosis. Four (21.1%) patients on aspirin had one or more episodes of catheter malfunction because of central venous catheter thrombosis ( p > 0.05), while nine (47.4%) out of the 19 control patients had tunneled catheter thrombosis with catheter malfunction ( p < 0.01). Malfunction-free catheter survival at 12 months was 75% in the warfarin group, 68.4% in the aspirin group, and 36.8% in the control group. There was no statistically significant difference between the warfarin and aspirin groups, while the difference between the warfarin or aspirin group and the control group was statistically significant ( p < 0.01). These results suggest that both warfarin and aspirin are effective in preventing tunneled hemodialysis catheter thrombosis and increasing long-term malfunction-free catheter survival.