RESUMEN
Tinzaparin offers some advantages over unfractionated heparin (UFH) for hemodialysis circuit anticoagulation. No study has compared these two molecules as hemodialysis catheter locks. This study aimed to compare the efficacy of tinzaparin and UFH as locks for hemodialysis tunnelled central venous catheter in patients with end-stage renal disease (ESRD). A randomized, prospective, single-blinded, controlled study was undertaken. Patients were randomly assigned to receive UFH and tinzaparin for two 7-week periods in a crossover fashion. The doses used were 5,000 U of UFH and 2,000 U of tinzaparin per catheter line. The primary outcome was the need for thrombolytic catheter lock use defined with the Hemodialysis Unit alteplase protocol. Forty-two patients with ESRD were enrolled, totalling 815 UFH lock sessions and 729 tinzaparin lock sessions. A 47.4% reduction in the incidence of alteplase lock use was observed with tinzaparin lock (3.16% vs. 6.01%, chi-square, p = 0.0078). There was no significant difference in the time to first alteplase use between the two locks by Kaplan-Meier survival analysis (logrank, p = 0.0900). Our results suggest that tinzaparin could be an appropriate alternative for a hemodialysis tunnelled central venous catheter lock, but these results should be confirmed with a larger trial.